题目内容
Scher, of Uniformed Services University, in Bethesda, Maryland, and colleagues assessed re ports of major life changes among 206 men and women who met criteria for chronic daily headache (180 or more headache days per year). They assessed similar reports from 507 men and women with "episodic" headache (2 to 104 headache days per year).
The investigators assessed changes in work, marital status, children's status, or residence; as well as deaths of family or close friends. They also inquired about self-defined "extremely stressful situations," such as financial problems, an ongoing individual illness or that of a family member, or an ongoing abusive relationship. Compared with men and women with episodic headache, men and women with chronic daily headache were more likely to have experienced major life events in the 2-year period prior to the onset of their headache condition, the researchers report in the medical journal Cephalalgia.
The strongest predictor of chronic daily headache was an ongoing extremely stressful situation. The researchers also noted a higher proportion of chronic daily headache among people 40 years and older. In this group, "a change in work status was related to increased risk for chronic daily headache, while in contrast, those younger than 40 years showed a decreased risk for chronic daily headache after a job change," Scher told Reuters Health.
These findings are generally consistent with prior research related to other chronic pain conditions, the investigators note. "Our finding that the relationship may be stronger for those older than 40 was an interesting, but secondary, finding that should be replicated in other samples," Scher said.
What does the word "precipitate" most probably mean？
查看答案
搜索结果不匹配？点我反馈
更多问题
How should we understand the process of oscillation？
What is the suggestion given by the author in this passage about the core differences between two people？
Which one of the following is NOT true about the experiment mentioned in Paragraph 4 ？
Part A
Directions: Read the following four texts. Answer the questions below each text by choosing A, B, C or D. (40 points)
The unknown pervades the universe. That which people can see, with the aid of various sorts of telescope, accounts for just 4% of the total mass. The rest, however, must exist. Without it, galaxies would not survive and the universe would not be gently expanding, as witnessed by astronomers. What exactly constitutes this dark matter and dark energy remains mysterious, but physicists have recently uncovered some more clues, about the former, at least.
One possible explanation for dark matter is a group of subatomic particles called neutrinos. Neutrinos are thought to be the most abundant particles in the universe. According to the Standard Model, the most successful description of particle physics to date, neutrinos come in three varieties, called "flavors". Again, according to the Standard Model, they are point-like, electrically neutral and massless. But in recent years, this view has been challenged, as physicists realized that neutrinos might have mass.
The first strong evidence came in 1998, when researchers at an experiment, based in Japan, showed that muon neutrinos produced by cosmic rays hitting the upper atmosphere had gone missing by the time they should have reached an underground detector. Its operators suspect that the missing muon neutrinos had changed flavor, becoming electron neutrinos or-more likely-tau neutrinos. Theo- ry suggests that this process, called oscillation, can happen only if neutrinos have mass.
Over the coming months and years, researchers hope to produce the most accurate measurements yet. The researchers created a beam of muon neutrinos first. On the other side of the target sat a particle detector that monitored the number of muon neutrinos leaving. The neutrinos then travelled 750km (450 miles) through the Earth to a detector in a former iron mine in Soudan, Minnesota. Researchers then were able to confirm that a significant number of muon neutrinos had disappeared-that is, they had changed flavor. While their mass is so small that neutrinos cannot be the sole constituent of dark matter, they have an advantage in that they are at least known to exist.
The same cannot be said for sure of another possible form. of dark matter being studied by a group of physicists in Italy. If the result continues to withstand scrutiny, it would appear to be evidence for an exotic new sort of fundamental particle, known as an axion, which could also be a type of dark matter.
What does the word "pervades"(Line 1, Para. 1) mean？
微信支付 
支付宝支付