首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   244篇
  免费   20篇
耳鼻咽喉   2篇
儿科学   6篇
妇产科学   4篇
基础医学   50篇
口腔科学   1篇
临床医学   22篇
内科学   56篇
皮肤病学   2篇
神经病学   34篇
特种医学   3篇
外科学   19篇
综合类   1篇
一般理论   1篇
预防医学   15篇
眼科学   1篇
药学   15篇
中国医学   2篇
肿瘤学   30篇
  2023年   2篇
  2021年   4篇
  2020年   7篇
  2019年   3篇
  2018年   18篇
  2017年   12篇
  2016年   5篇
  2015年   8篇
  2014年   5篇
  2013年   9篇
  2012年   25篇
  2011年   26篇
  2010年   8篇
  2009年   5篇
  2008年   14篇
  2007年   15篇
  2006年   13篇
  2005年   15篇
  2004年   11篇
  2003年   7篇
  2002年   10篇
  2001年   1篇
  1999年   2篇
  1998年   2篇
  1997年   3篇
  1996年   1篇
  1995年   1篇
  1992年   3篇
  1991年   1篇
  1990年   4篇
  1989年   2篇
  1987年   2篇
  1986年   2篇
  1985年   1篇
  1984年   2篇
  1981年   2篇
  1980年   1篇
  1979年   3篇
  1978年   1篇
  1977年   1篇
  1974年   1篇
  1971年   2篇
  1965年   1篇
  1935年   2篇
  1933年   1篇
排序方式: 共有264条查询结果,搜索用时 15 毫秒
11.
12.
OBJECTIVE: The authors examined the effectiveness of unguided self-help as a first step in the treatment of bulimia nervosa. METHOD: A total of 85 women with bulimia nervosa who were on a waiting list for treatment at a hospital-based clinic participated. The patients were randomly assigned to receive one of two self-help manuals or to a waiting list control condition for 8 weeks. One of the self-help manuals addressed the specific symptoms of bulimia nervosa (cognitive behavior self-help), while the other focused on self-assertion skills (nonspecific self-help). RESULTS: Twenty patients (23.5%) dropped out of the study. The data were analyzed with intention-to-treat analysis. Although the group-by-time interaction for binge eating and purging was not statistically significant, simple effects showed that there was a significant reduction in symptom frequency in both self-help conditions at posttreatment but not in the waiting list condition. There were no statistically significant changes in levels of dietary restraint, eating concerns, concerns about shape and weight, or general psychopathology. A greater proportion of patients in the cognitive behavior self-help (53.6%) and nonspecific self-help (50.0%) conditions reported at least a 50% reduction in binge eating or purging at posttreatment, compared with the waiting list condition (31.0%). A lower baseline knowledge about eating disorders, more problems with intimacy, and higher compulsivity scores predicted a better response. CONCLUSIONS: The findings suggest that a subgroup of patients with bulimia nervosa may benefit from unguided self-help as a first step in their treatment. Cognitive behavior self-help and nonspecific self-help had equivalent effects.  相似文献   
13.
During the past decade pharmaceutical companies have been faced with the withdrawal of some of their marketed drugs because of rare, yet lethal, postmarketing reports associated with ventricular arrhythmias. The implicated drugs include antiarrhythmics, but also non-cardiac drugs, such as histamine blockers, antipsychotics, and antibiotics. These undesired effects involve prolongation of the QT interval, which may lead to characteristic ventricular tachyarrhythmias, known as torsades de pointes. These clinical symptoms of the acquired long QT syndrome (LQTS) are also found in an inherited form of the disease, called congenital LQTS. Nowadays, a number of environmental (non-genetic) and genetic risk factors for acquired LQTS have been described. Non-genetic factors include female gender, hypokalemia, and other heart diseases. The knowledge of genetic risk factors is emerging rapidly. During the last decade, mutations in several genes encoding ion channels have been shown to cause congenital LQTS. In acquired LQTS, a number of 'silent' mutation carriers in these LQTS genes have been identified, and functional polymorphisms in the same genes have been found that are associated with an increased vulnerability for the disease. Furthermore, there is also evidence that interindividual differences in drug metabolism, caused by functional polymorphisms in drug-metabolizing enzyme genes, may be a risk factor for acquired LQTS, especially if multiple drugs are involved. This review evaluates the current knowledge on these risk factors for acquired LQTS, with an emphasis on the genetic risk factors. It also assesses the potential to develop pharmacogenetic tests that will enable clinicians and pharmaceutical companies to identify at an early stage patients or individuals in the general population who are at risk of acquired LQTS.  相似文献   
14.
15.
Two pentacyclic triterpenes, 1alpha,3beta-dihydroxybauer-7-en-28-oic acid (1) and 3beta-hydroxybauer-7-en-28-oic acid (2), together with sitosterol-3-beta-O-d-glucopyranoside and stigmasterol have been isolated from the bark of the plant Maesopsis eminii. Their structures have been elucidated by spectroscopic methods. One of the triterpenes (1) is new, and its structure was confirmed by X-ray crystallographic analysis. This new triterpene displayed moderate antibacterial activity against Bacillus subtilis ATCC 6633.  相似文献   
16.
17.

Background  

Recent evidence, both animal and human, suggests that modifiable factors during fetal and infant development predispose for cardiovascular disease in adult life and that they may become possible future targets for prevention. One of these factors is maternal psychosocial stress, but so far, few prospective studies have been able to investigate the longer-term effects of stress in detail, i.e. effects in childhood. Therefore, our general aim is to study whether prenatal maternal psychosocial stress is associated with an adverse cardio-metabolic risk profile in the child at age five.  相似文献   
18.
We assessed in the laboratory the attraction of the parasitoid Cotesia marginiventris (Cresson) toward odors emitted by conventional maize (Zea mays L. ssp. mays) and Bt (Bacillus thuringiensis) maize seedlings following actual or simulated injury by Spodoptera frugiperda (Smith), the parasitoid’s host, and emitted by the host’s frass, produced following consumption of conventional or Bt maize seedlings. Females of C. marginiventris exhibited similarly strong responses to conventional and Bt maize seedlings injured by the host or with simulated injury, and these were stronger than responses to clean air. In contrast, the responses of C. marginiventris females were consistently weaker toward host frass derived from Bt maize tissue compared to frass derived from conventional maize tissue. We hypothesized that the weakened response was due to a detrimental effect of Bt endotoxins, present in the Bt maize tissue, on the bacterial community present in the host’s gut and frass, including bacteria that produce odors attractive to C. marginiventris. As an initial test of our hypothesis, we compared between the responses of C. marginiventris females to host frass produced following consumption of Bt maize and frass produced from conventional maize which had been treated with an antibiotic (tetracycline) to eliminate host gut bacteria. Our results showed that C. marginiventris females responded similarly weakly to host frass derived from conventional maize tissue treated with antibiotic and to frass derived from Bt maize tissue, treated or untreated with antibiotic, while they responded strongly to frass derived from conventional maize untreated with antibiotic, so provided initial, partial support for our hypothesis. We discussed the weakened response of C. marginiventris females to host frass derived from Bt maize in the context of plausible impacts of transgenic crop cultivars on parasitoid foraging and populations, and the implications for biological control of non-target, polyphagous pests, such as S. frugiperda.  相似文献   
19.
Drug-induced torsade de pointes arrhythmia (TdP) is frequently seen in patients. This proarrhythmia is not restricted to anti-arrhythmics but includes a variety of drugs. A genetic predisposition is an attractive explanation for this clinical problem. In this review, we: 1) explain the arrhythmogenic mechanisms of TdP, 2) provide data for a genetic cause based upon mutations in the long QT or in cytochrome genes responsible for drug metabolism, and 3) present pathology-based electrical remodeling as an alternative explanation. It can be concluded that the current evidence for a genetic basis for drug-induced TdP is weak.  相似文献   
20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号