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21 tháng 11 2025

gì vậy trời

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.The pain of a migraine headache can virtually disable a person who suffers from it. Millions and millions of people suffer from migraines, although many of them do not even recognize that a migraine is different from a regular headache. A migraine is not at all the same as a normal headache, and it seems to have a very physical cause.One symptom of a migraine...
Đọc tiếp

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.

The pain of a migraine headache can virtually disable a person who suffers from it. Millions and millions of people suffer from migraines, although many of them do not even recognize that a migraine is different from a regular headache. A migraine is not at all the same as a normal headache, and it seems to have a very physical cause.

One symptom of a migraine is a precursor, which is a visual aura before an attack. Yet only about a third of patients actually experience that, and it is, therefore, not a requirement in the diagnosis. Other symptoms include increased pain when a person moves, nausea, and sensitivity to light and sound.

Scientists now believe that migraines are caused, not by abnormal blood vessels as previously believed, but instead by a unique electrical disorder of brain cells. Physicians used to treat migraines with medicine to constrict blood vessels because of the belief that dilated blood vessels were the cause. The new research has been enhanced by imaging devices that allow scientists to watch patients’ brains during an attack. The results show that sufferers have abnormally excitable neurons, or brain nerve cells. Prior to the attack, the neurons suddenly fire off electrical pulses at the back of the brain, which ripple like waves on a lake after a stone hits the water. They ripple across the top and then the back of the brain, ultimately affecting the brain stem where the pain centers are located. The pain then generates possibly from the brain stem itself or from blood vessels inflamed by the rapidly changingblood flow, or perhaps from both.

Scientists have experimented by applying a powerful magnet to stimulate the neurons and discovered that some people’s brains react differently than others’. When stimulation was applied to the brains of people who had suffered migraines, they saw the initial aura, and some actually suffered migraines. When the same stimulation was applied to the brains of people who had never suffered migraines, they realized no effect and the neurons showed no change.

Scientists and doctors continue to work on the research in an attempt to find the perfect treatment. It is considered important to treat migraines because it is believed that prolonged untreated attacks could cause physical changes in the brain leading to chronic pain.

Scientists have caused neurons to react by applying_________.

1
4 tháng 7 2018

Đáp án : C

Dấu hiệu: câu 1 đoạn 4 “Scientists have experimented by applying a powerful magnet to stimulate the neurons” : các nhà khoa học thí nghiệm bởi việc sử dụng một sức hút mạnh để kích thích các nơ ron.-> “ a magnet field”.

 

Read the following passage and mark the letter (A, B, C or D) on your answer sheet to indicate the correct answer to each for the questions.  The pain of a migraine headache can virtually disable a person who suffers from it. Millions and millions of people suffer from migraines, although many of them do not even recognize that a migraine is different from a regular headache. A migraine is not at all the same as a normal headache, and it seems to have a very physical cause. One symptom of a...
Đọc tiếp

Read the following passage and mark the letter (A, B, C or D) on your answer sheet to indicate the correct answer to each for the questions.

 The pain of a migraine headache can virtually disable a person who suffers from it. Millions and millions of people suffer from migraines, although many of them do not even recognize that a migraine is different from a regular headache. A migraine is not at all the same as a normal headache, and it seems to have a very physical cause.

 One symptom of a migraine is a precursor, which is a visual aura before an attack. Yet only about a third of patients actually experience that, and it is therefore not a requirement in the diagnosis. Other symptoms include increased pain when a person moves, nausea, and sensitivity to light and sound. Scientists now believe that migraines are caused, not by abnormal blood vessels as previously believed, but instead by a unique electrical disorder of brain cells. Physicians used to treat migraines with medicine to constrict blood vessels because of the belief that dilated blood vessels were the cause.

 The new research has been enhanced by imaging devices that allow scientists to watch patients' brains during an attack. The results show that sufferers have abnormally excitable neurons, or brain nerve cells. Prior to the attack, the neurons suddenly fire off electrical pulses at the back of the brain, which ripple like waves on a lake after a stone hits the water. They ripple across the top and then the back of the brain, ultimately affecting the brain stem where the pain centers are located. The pain then generates possibly from the brain stem itself or from blood vessels inflamed by the rapidly changing blood flow, or perhaps from both.

 Scientists have experimented by applying a powerful magnet to stimulate the neurons and discovered that some people's brains react differently than others'. When stimulation was applied to the brains of people who had suffered migraines, they saw the initial aura, and some actually suffered migraines. When the same stimulation was applied to the brains of people who had never suffered migraines, they realized no effect and the neurons showed no change.

 Scientists and doctors continue to work on the research in an attempt to find the perfect treatment. It is considered important to treat migraines because it is believed that prolonged untreated attacks could cause physical changes in the brain leading to chronic pain.

The author implies that a migraine

1
3 tháng 10 2018

Đáp án là D.

Tác giả ngụ ý rằng chứng đau nửa đầu

A. chỉ là cơn đau đàu dữ dội

B. có thể chữa trị bằng thuốc giảm đau thông thường

C. bị gây ra bởi những thứ giống như nguyên nhân gây đau đầu.

D. có nguyên nhân khoa học riêng, không giống như đau đầu.

Dẫn chứng: A migraine is not at all the same as a normal headache, and it seems to have a very physical cause

Read the following passage and mark the letter (A, B, C or D) on your answer sheet to indicate the correct answer to each for the questions.  The pain of a migraine headache can virtually disable a person who suffers from it. Millions and millions of people suffer from migraines, although many of them do not even recognize that a migraine is different from a regular headache. A migraine is not at all the same as a normal headache, and it seems to have a very physical cause. One symptom of a...
Đọc tiếp

Read the following passage and mark the letter (A, B, C or D) on your answer sheet to indicate the correct answer to each for the questions.

 The pain of a migraine headache can virtually disable a person who suffers from it. Millions and millions of people suffer from migraines, although many of them do not even recognize that a migraine is different from a regular headache. A migraine is not at all the same as a normal headache, and it seems to have a very physical cause.

 One symptom of a migraine is a precursor, which is a visual aura before an attack. Yet only about a third of patients actually experience that, and it is therefore not a requirement in the diagnosis. Other symptoms include increased pain when a person moves, nausea, and sensitivity to light and sound. Scientists now believe that migraines are caused, not by abnormal blood vessels as previously believed, but instead by a unique electrical disorder of brain cells. Physicians used to treat migraines with medicine to constrict blood vessels because of the belief that dilated blood vessels were the cause.

 The new research has been enhanced by imaging devices that allow scientists to watch patients' brains during an attack. The results show that sufferers have abnormally excitable neurons, or brain nerve cells. Prior to the attack, the neurons suddenly fire off electrical pulses at the back of the brain, which ripple like waves on a lake after a stone hits the water. They ripple across the top and then the back of the brain, ultimately affecting the brain stem where the pain centers are located. The pain then generates possibly from the brain stem itself or from blood vessels inflamed by the rapidly changing blood flow, or perhaps from both.

 Scientists have experimented by applying a powerful magnet to stimulate the neurons and discovered that some people's brains react differently than others'. When stimulation was applied to the brains of people who had suffered migraines, they saw the initial aura, and some actually suffered migraines. When the same stimulation was applied to the brains of people who had never suffered migraines, they realized no effect and the neurons showed no change.

 Scientists and doctors continue to work on the research in an attempt to find the perfect treatment. It is considered important to treat migraines because it is believed that prolonged untreated attacks could cause physical changes in the brain leading to chronic pain.

The new research indicates that the neurons in the brain of migraine sufferers

1
11 tháng 9 2017

Đáp án là B.

Nghiên cứu mới cho thấy rằng những sợi dây thần kinh trong não của những người bị đau nửa đầu

A. có nhiều điện cực hơn những người không bị đau nửa đầu.

B. có xu hướng phát hỏa trạng thái bất thường khi chứng đau nửa đầu bắt đầu.

C. không phản ứng

D. không ảnh hưởng đến chứng đau nửa đầu

Dẫn chứng: The results show that sufferers have abnormally excitable neurons, or brain nerve cells

Read the following passage and mark the letter (A, B, C or D) on your answer sheet to indicate the correct answer to each for the questions.  The pain of a migraine headache can virtually disable a person who suffers from it. Millions and millions of people suffer from migraines, although many of them do not even recognize that a migraine is different from a regular headache. A migraine is not at all the same as a normal headache, and it seems to have a very physical cause. One symptom of a...
Đọc tiếp

Read the following passage and mark the letter (A, B, C or D) on your answer sheet to indicate the correct answer to each for the questions.

 The pain of a migraine headache can virtually disable a person who suffers from it. Millions and millions of people suffer from migraines, although many of them do not even recognize that a migraine is different from a regular headache. A migraine is not at all the same as a normal headache, and it seems to have a very physical cause.

 One symptom of a migraine is a precursor, which is a visual aura before an attack. Yet only about a third of patients actually experience that, and it is therefore not a requirement in the diagnosis. Other symptoms include increased pain when a person moves, nausea, and sensitivity to light and sound. Scientists now believe that migraines are caused, not by abnormal blood vessels as previously believed, but instead by a unique electrical disorder of brain cells. Physicians used to treat migraines with medicine to constrict blood vessels because of the belief that dilated blood vessels were the cause.

 The new research has been enhanced by imaging devices that allow scientists to watch patients' brains during an attack. The results show that sufferers have abnormally excitable neurons, or brain nerve cells. Prior to the attack, the neurons suddenly fire off electrical pulses at the back of the brain, which ripple like waves on a lake after a stone hits the water. They ripple across the top and then the back of the brain, ultimately affecting the brain stem where the pain centers are located. The pain then generates possibly from the brain stem itself or from blood vessels inflamed by the rapidly changing blood flow, or perhaps from both.

 Scientists have experimented by applying a powerful magnet to stimulate the neurons and discovered that some people's brains react differently than others'. When stimulation was applied to the brains of people who had suffered migraines, they saw the initial aura, and some actually suffered migraines. When the same stimulation was applied to the brains of people who had never suffered migraines, they realized no effect and the neurons showed no change.

 Scientists and doctors continue to work on the research in an attempt to find the perfect treatment. It is considered important to treat migraines because it is believed that prolonged untreated attacks could cause physical changes in the brain leading to chronic pain.

The word “it “ in paragraph 1 refers to 

1
27 tháng 12 2019

Đáp án là B.

Từ “it” ở đoạn 1 ám chỉ đến

A. vết thương

B. chứng đau nửa đầu

C. con người

D. sự chịu đựng

Dẫn chứng: The pain of a migraine headache can virtually disable a person who suffers from it

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.The pain of a migraine headache can virtually disable a person who suffers from it. Millions and millions of people suffer from migraines, although many of them do not even recognize that a migraine is different from a regular headache. A migraine is not at all the same as a normal headache, and it seems to have a very physical cause.One symptom of a migraine...
Đọc tiếp

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.

The pain of a migraine headache can virtually disable a person who suffers from it. Millions and millions of people suffer from migraines, although many of them do not even recognize that a migraine is different from a regular headache. A migraine is not at all the same as a normal headache, and it seems to have a very physical cause.

One symptom of a migraine is a precursor, which is a visual aura before an attack. Yet only about a third of patients actually experience that, and it is, therefore, not a requirement in the diagnosis. Other symptoms include increased pain when a person moves, nausea, and sensitivity to light and sound.

Scientists now believe that migraines are caused, not by abnormal blood vessels as previously believed, but instead by a unique electrical disorder of brain cells. Physicians used to treat migraines with medicine to constrict blood vessels because of the belief that dilated blood vessels were the cause. The new research has been enhanced by imaging devices that allow scientists to watch patients’ brains during an attack. The results show that sufferers have abnormally excitable neurons, or brain nerve cells. Prior to the attack, the neurons suddenly fire off electrical pulses at the back of the brain, which ripple like waves on a lake after a stone hits the water. They ripple across the top and then the back of the brain, ultimately affecting the brain stem where the pain centers are located. The pain then generates possibly from the brain stem itself or from blood vessels inflamed by the rapidly changingblood flow, or perhaps from both.

Scientists have experimented by applying a powerful magnet to stimulate the neurons and discovered that some people’s brains react differently than others’. When stimulation was applied to the brains of people who had suffered migraines, they saw the initial aura, and some actually suffered migraines. When the same stimulation was applied to the brains of people who had never suffered migraines, they realized no effect and the neurons showed no change.

Scientists and doctors continue to work on the research in an attempt to find the perfect treatment. It is considered important to treat migraines because it is believed that prolonged untreated attacks could cause physical changes in the brain leading to chronic pain.

The new research indicates that the neurons in the brain of migraine sufferers _________.

1
23 tháng 6 2018

Đáp án : C

“sufferers have abnormally excitable neurons” bệnh nhân có có nơ ron bị kích thich bất thường-> Đáp án C làm nóng các mẫu bất thường. Đáp án A không đề cập trong bài. Đáp án B,D có nội dung sai.

 

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.The pain of a migraine headache can virtually disable a person who suffers from it. Millions and millions of people suffer from migraines, although many of them do not even recognize that a migraine is different from a regular headache. A migraine is not at all the same as a normal headache, and it seems to have a very physical cause.One symptom of a migraine...
Đọc tiếp

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.

The pain of a migraine headache can virtually disable a person who suffers from it. Millions and millions of people suffer from migraines, although many of them do not even recognize that a migraine is different from a regular headache. A migraine is not at all the same as a normal headache, and it seems to have a very physical cause.

One symptom of a migraine is a precursor, which is a visual aura before an attack. Yet only about a third of patients actually experience that, and it is, therefore, not a requirement in the diagnosis. Other symptoms include increased pain when a person moves, nausea, and sensitivity to light and sound.

Scientists now believe that migraines are caused, not by abnormal blood vessels as previously believed, but instead by a unique electrical disorder of brain cells. Physicians used to treat migraines with medicine to constrict blood vessels because of the belief that dilated blood vessels were the cause. The new research has been enhanced by imaging devices that allow scientists to watch patients’ brains during an attack. The results show that sufferers have abnormally excitable neurons, or brain nerve cells. Prior to the attack, the neurons suddenly fire off electrical pulses at the back of the brain, which ripple like waves on a lake after a stone hits the water. They ripple across the top and then the back of the brain, ultimately affecting the brain stem where the pain centers are located. The pain then generates possibly from the brain stem itself or from blood vessels inflamed by the rapidly changingblood flow, or perhaps from both.

Scientists have experimented by applying a powerful magnet to stimulate the neurons and discovered that some people’s brains react differently than others’. When stimulation was applied to the brains of people who had suffered migraines, they saw the initial aura, and some actually suffered migraines. When the same stimulation was applied to the brains of people who had never suffered migraines, they realized no effect and the neurons showed no change.

Scientists and doctors continue to work on the research in an attempt to find the perfect treatment. It is considered important to treat migraines because it is believed that prolonged untreated attacks could cause physical changes in the brain leading to chronic pain.

The best title for this passage would be what?

1
12 tháng 11 2018

Đáp án : C

Đáp án A: Hình ảnh là 1 phương pháp nghiên cứu  đau nửa đầu-> đúng nhưng chỉ là 1 ý nhỏ. Đáp án B: Phương pháp mới chữa đau nửa đầu-> Sai vì phương pháp chữa vẫn đang được tìm kiếm: “Scientists and doctors continue to work on the research in an attempt to find the perfect treatment.” Đáp án C:Dấu hiệu mới về cách đau nửa đầu hình thành-> Đúng vì trong bài xuất hiện nhiều từ “cause” (nguyên nhân), Đáp án D: sự khác biệt giữa đau đầu và đau nửa đầu-> Đúng nhưng chỉ là 1 ý nhỏ.

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.The pain of a migraine headache can virtually disable a person who suffers from it. Millions and millions of people suffer from migraines, although many of them do not even recognize that a migraine is different from a regular headache. A migraine is not at all the same as a normal headache, and it seems to have a very physical cause.One symptom of a migraine...
Đọc tiếp

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.

The pain of a migraine headache can virtually disable a person who suffers from it. Millions and millions of people suffer from migraines, although many of them do not even recognize that a migraine is different from a regular headache. A migraine is not at all the same as a normal headache, and it seems to have a very physical cause.

One symptom of a migraine is a precursor, which is a visual aura before an attack. Yet only about a third of patients actually experience that, and it is, therefore, not a requirement in the diagnosis. Other symptoms include increased pain when a person moves, nausea, and sensitivity to light and sound.

Scientists now believe that migraines are caused, not by abnormal blood vessels as previously believed, but instead by a unique electrical disorder of brain cells. Physicians used to treat migraines with medicine to constrict blood vessels because of the belief that dilated blood vessels were the cause. The new research has been enhanced by imaging devices that allow scientists to watch patients’ brains during an attack. The results show that sufferers have abnormally excitable neurons, or brain nerve cells. Prior to the attack, the neurons suddenly fire off electrical pulses at the back of the brain, which ripple like waves on a lake after a stone hits the water. They ripple across the top and then the back of the brain, ultimately affecting the brain stem where the pain centers are located. The pain then generates possibly from the brain stem itself or from blood vessels inflamed by the rapidly changingblood flow, or perhaps from both.

Scientists have experimented by applying a powerful magnet to stimulate the neurons and discovered that some people’s brains react differently than others’. When stimulation was applied to the brains of people who had suffered migraines, they saw the initial aura, and some actually suffered migraines. When the same stimulation was applied to the brains of people who had never suffered migraines, they realized no effect and the neurons showed no change.

 

Scientists and doctors continue to work on the research in an attempt to find the perfect treatment. It is considered important to treat migraines because it is believed that prolonged untreated attacks could cause physical changes in the brain leading to chronic pain.

The author implies that a migraine_________.

1
3 tháng 7 2018

Đáp án : D

“a migraine is different from a regular headache”: một cơn đau nửa đầu thì khác so với đau đầu.->Chọn dáp án D “unlike a headache”.

 

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.The pain of a migraine headache can virtually disable a person who suffers from it. Millions and millions of people suffer from migraines, although many of them do not even recognize that a migraine is different from a regular headache. A migraine is not at all the same as a normal headache, and it seems to have a very physical cause.One symptom of a migraine...
Đọc tiếp

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.

The pain of a migraine headache can virtually disable a person who suffers from it. Millions and millions of people suffer from migraines, although many of them do not even recognize that a migraine is different from a regular headache. A migraine is not at all the same as a normal headache, and it seems to have a very physical cause.

One symptom of a migraine is a precursor, which is a visual aura before an attack. Yet only about a third of patients actually experience that, and it is, therefore, not a requirement in the diagnosis. Other symptoms include increased pain when a person moves, nausea, and sensitivity to light and sound.

Scientists now believe that migraines are caused, not by abnormal blood vessels as previously believed, but instead by a unique electrical disorder of brain cells. Physicians used to treat migraines with medicine to constrict blood vessels because of the belief that dilated blood vessels were the cause. The new research has been enhanced by imaging devices that allow scientists to watch patients’ brains during an attack. The results show that sufferers have abnormally excitable neurons, or brain nerve cells. Prior to the attack, the neurons suddenly fire off electrical pulses at the back of the brain, which ripple like waves on a lake after a stone hits the water. They ripple across the top and then the back of the brain, ultimately affecting the brain stem where the pain centers are located. The pain then generates possibly from the brain stem itself or from blood vessels inflamed by the rapidly changingblood flow, or perhaps from both.

Scientists have experimented by applying a powerful magnet to stimulate the neurons and discovered that some people’s brains react differently than others’. When stimulation was applied to the brains of people who had suffered migraines, they saw the initial aura, and some actually suffered migraines. When the same stimulation was applied to the brains of people who had never suffered migraines, they realized no effect and the neurons showed no change.

Scientists and doctors continue to work on the research in an attempt to find the perfect treatment. It is considered important to treat migraines because it is believed that prolonged untreated attacks could cause physical changes in the brain leading to chronic pain

The prior treatment for migraines included medicine that_________.

 

1
14 tháng 8 2017

Đáp án : A

Dựa vào dòng 3 đoạn 3: “Physicians used to treat migraines with medicine to constrict blood vessels” các thầy thuốc điều trị đau nửa đầu bằng thuốc làm co thắt mạch máu. Constrict= tighten= siết chặt.

 

Read the following passage and mark the letter (A, B, C or D) on your answer sheet to indicate the correct answer to each for the questions.  The pain of a migraine headache can virtually disable a person who suffers from it. Millions and millions of people suffer from migraines, although many of them do not even recognize that a migraine is different from a regular headache. A migraine is not at all the same as a normal headache, and it seems to have a very physical cause. One symptom of a...
Đọc tiếp

Read the following passage and mark the letter (A, B, C or D) on your answer sheet to indicate the correct answer to each for the questions.

 The pain of a migraine headache can virtually disable a person who suffers from it. Millions and millions of people suffer from migraines, although many of them do not even recognize that a migraine is different from a regular headache. A migraine is not at all the same as a normal headache, and it seems to have a very physical cause.

 One symptom of a migraine is a precursor, which is a visual aura before an attack. Yet only about a third of patients actually experience that, and it is therefore not a requirement in the diagnosis. Other symptoms include increased pain when a person moves, nausea, and sensitivity to light and sound. Scientists now believe that migraines are caused, not by abnormal blood vessels as previously believed, but instead by a unique electrical disorder of brain cells. Physicians used to treat migraines with medicine to constrict blood vessels because of the belief that dilated blood vessels were the cause.

 The new research has been enhanced by imaging devices that allow scientists to watch patients' brains during an attack. The results show that sufferers have abnormally excitable neurons, or brain nerve cells. Prior to the attack, the neurons suddenly fire off electrical pulses at the back of the brain, which ripple like waves on a lake after a stone hits the water. They ripple across the top and then the back of the brain, ultimately affecting the brain stem where the pain centers are located. The pain then generates possibly from the brain stem itself or from blood vessels inflamed by the rapidly changing blood flow, or perhaps from both.

 Scientists have experimented by applying a powerful magnet to stimulate the neurons and discovered that some people's brains react differently than others'. When stimulation was applied to the brains of people who had suffered migraines, they saw the initial aura, and some actually suffered migraines. When the same stimulation was applied to the brains of people who had never suffered migraines, they realized no effect and the neurons showed no change.

 Scientists and doctors continue to work on the research in an attempt to find the perfect treatment. It is considered important to treat migraines because it is believed that prolonged untreated attacks could cause physical changes in the brain leading to chronic pain.

The prior treatment for migraines included medicine that 

1
1 tháng 3 2017

Đáp án là B.

Phương pháp chữa trị tối ưu cho chứng đau nửa đầu bao gồm

A. loại bỏ cơn đau

B. thắt chặt mạch máu

C. loại bỏ cơn đau thoáng qua

D. loại bỏ căng thẳng

Dẫn chứng: Physicians used to treat migraines with medicine to constrict blood vessels because of the belief that dilated blood vessels were the cause

Read the following passage and mark the letter (A, B, C or D) on your answer sheet to indicate the correct answer to each for the questions.  The pain of a migraine headache can virtually disable a person who suffers from it. Millions and millions of people suffer from migraines, although many of them do not even recognize that a migraine is different from a regular headache. A migraine is not at all the same as a normal headache, and it seems to have a very physical cause. One symptom of a...
Đọc tiếp

Read the following passage and mark the letter (A, B, C or D) on your answer sheet to indicate the correct answer to each for the questions.

 The pain of a migraine headache can virtually disable a person who suffers from it. Millions and millions of people suffer from migraines, although many of them do not even recognize that a migraine is different from a regular headache. A migraine is not at all the same as a normal headache, and it seems to have a very physical cause.

 One symptom of a migraine is a precursor, which is a visual aura before an attack. Yet only about a third of patients actually experience that, and it is therefore not a requirement in the diagnosis. Other symptoms include increased pain when a person moves, nausea, and sensitivity to light and sound. Scientists now believe that migraines are caused, not by abnormal blood vessels as previously believed, but instead by a unique electrical disorder of brain cells. Physicians used to treat migraines with medicine to constrict blood vessels because of the belief that dilated blood vessels were the cause.

 The new research has been enhanced by imaging devices that allow scientists to watch patients' brains during an attack. The results show that sufferers have abnormally excitable neurons, or brain nerve cells. Prior to the attack, the neurons suddenly fire off electrical pulses at the back of the brain, which ripple like waves on a lake after a stone hits the water. They ripple across the top and then the back of the brain, ultimately affecting the brain stem where the pain centers are located. The pain then generates possibly from the brain stem itself or from blood vessels inflamed by the rapidly changing blood flow, or perhaps from both.

 Scientists have experimented by applying a powerful magnet to stimulate the neurons and discovered that some people's brains react differently than others'. When stimulation was applied to the brains of people who had suffered migraines, they saw the initial aura, and some actually suffered migraines. When the same stimulation was applied to the brains of people who had never suffered migraines, they realized no effect and the neurons showed no change.

 Scientists and doctors continue to work on the research in an attempt to find the perfect treatment. It is considered important to treat migraines because it is believed that prolonged untreated attacks could cause physical changes in the brain leading to chronic pain.

According to the passage, now that scientists know that unusual neurons in certain people are the cause of migraines, they

1
9 tháng 4 2017

Đáp án là C.

Theo bài đọc, ngày nay các nhà khoa học biết rằng dây thần kinh bất thường ở một số người nhất định là nguyên nhân của chứng đau nửa đầu, họ

A. biết rằng tất cả họ cần biết về nguyên nhân gây ra chứng đau nửa đầu.

B. đã phát triển thuốc để giữ lại điện của dây thần kinh

C. vẫn chưa biết chính xác nguyên nhân gây ra cơn đau.

D. biết rằng những dây thần kinh khuyết tật trú ngụ trong thân não

Dẫn chứng: The pain then generates possibly from the brain stem itself or from blood vessels inflamed by the rapidly changing blood flow, or perhaps from both