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   3890篇
  免费   179篇
  国内免费   11篇
耳鼻咽喉   37篇
儿科学   288篇
妇产科学   206篇
基础医学   429篇
口腔科学   76篇
临床医学   202篇
内科学   775篇
皮肤病学   171篇
神经病学   203篇
特种医学   160篇
外科学   743篇
综合类   89篇
预防医学   147篇
眼科学   101篇
药学   173篇
中国医学   14篇
肿瘤学   266篇
  2023年   37篇
  2022年   61篇
  2021年   128篇
  2020年   70篇
  2019年   90篇
  2018年   122篇
  2017年   100篇
  2016年   107篇
  2015年   92篇
  2014年   168篇
  2013年   176篇
  2012年   267篇
  2011年   306篇
  2010年   174篇
  2009年   136篇
  2008年   205篇
  2007年   184篇
  2006年   194篇
  2005年   133篇
  2004年   142篇
  2003年   111篇
  2002年   106篇
  2001年   89篇
  2000年   70篇
  1999年   70篇
  1998年   41篇
  1997年   30篇
  1996年   32篇
  1995年   24篇
  1994年   16篇
  1993年   14篇
  1992年   39篇
  1991年   46篇
  1990年   52篇
  1989年   41篇
  1988年   48篇
  1987年   38篇
  1986年   33篇
  1985年   28篇
  1984年   18篇
  1983年   22篇
  1979年   13篇
  1978年   14篇
  1977年   15篇
  1976年   18篇
  1975年   19篇
  1973年   17篇
  1972年   20篇
  1971年   15篇
  1970年   15篇
排序方式: 共有4080条查询结果,搜索用时 15 毫秒
91.
Background:Many pediatric forearm fractures can be treated in plaster following closed reduction. The cast index (CI, a ratio of anteroposterior to lateral internal diameters of the cast at the fracture site) is a simple, reliable marker of quality of molding and a CI of >0.8 correlates with increased risk of redisplacement. Previously, CI has been applied to all forearm fractures. We hypothesize that an acceptable CI is more difficult to achieve and does not predict outcome in fractures of the proximal forearm.Results:The mean CI was 0.77. Remanipulation was required in five cases (6%), all distal half fractures – mean CI 0.79. CI was higher in proximal half forearm fractures (0.83 vs. 0.76, P = 0.006), nonetheless these fractures did not re-displace more than distal fractures.Conclusion:Cast index is useful in predicting redisplacement of manipulated distal forearm fractures. We found that in proximal half forearm fractures it is difficult to achieve a CI of <0.8, but increased CI does not predict loss of position in these fractures. We therefore discourage the use of CI in proximal half forearm fractures.  相似文献   
92.
93.
Epigenetic influences, such as DNA methylation, histone acetylation, and up‐regulation/down‐regulation of genes by microRNAs, change the genetic makeup of an individual without affecting DNA base‐pair sequences. Indeed, epigenetic changes play an integral role in the progression from normal esophageal mucosa to Barrett''s esophagus to esophageal adenocarcinoma via dysplasia–metaplasia–neoplasia sequence. Many genes involved in esophageal adenocarcinoma display hypermethylation, leading to their down‐regulation. The classes of these genes include cell cycle control, DNA and growth factor repair, tumor suppressors, antimetastasis, Wnt‐related genes, and proapoptotic genes. Histone acetylation in the pathophysiology of esophageal diseases has not been thoroughly investigated, and its critical role in the development of esophageal adenocarcinoma is less defined. Many microRNAs have been associated with the development of Barrett''s esophagus and esophageal adenocarcinoma. Here, we critically addressed the specific steps most closely influenced by microRNAs in the progression from Barrett''s esophagus to esophageal adenocarcinoma. However, microRNAs can target up to hundreds of genes, making it difficult to correlate directly with a given phenotype of the disease. Esophageal adenocarcinoma progressing from premalignant condition of Barrett''s esophagus carries an extremely poor prognosis. Risk stratification for patients based on their epigenetic profiles may be useful in providing more targeted and directed treatment to patients.  相似文献   
94.
95.
The effects of oral treatment with coenzyme Q10 (120 mg/d) were compared for 28 days in 73 (intervention group A) and 71 (placebo group B) patients with acute myocardial infarction (AMI). After treatment, angina pectoris (9.5 vs. 28.1), total arrhythmias (9.5% vs. 25.3%), and poor left ventricular function (8.2% vs. 22.5%) were significantly (P < 0.05) reduced in the coenzyme Q group than placebo group. Total cardiac events, including cardiac deaths and nonfatal infarction, were also significantly reduced in the coenzyme Q10 group compared with the placebo group (15.0% vs. 30.9%, P < 0.02). The extent of cardiac disease, elevation in cardiac enzymes, and oxidative stress at entry to the study were comparable between the two groups. Lipid peroxides, diene conjugates, and malondialdehyde, which are indicators of oxidative stress, showed a greater reduction in the treatment group than in the placebo group. The antioxidants vitamin A, E, and C and beta-carotene, which were lower initially after AMI, increased more in the coenzyme Q10 group than in the placebo group. These findings suggest that coenzyme Q10 can provide rapid protective effects in patients with AMI if administered within 3 days of the onset of symptoms. More studies in a larger number of patients and long-term follow-up are needed to confirm our results.  相似文献   
96.
97.
98.

Background:

Aluminum phosphide (ALP) (celphos) is an agricultural pesticide commonly implicated in poisoning. Literature pertaining to the clinical manifestations and treatment outcome of its poisoning among children is limited.

Materials and Methods:

A retrospective chart review was conducted of the medical records of 30 children aged less than 14 years admitted to pediatric intensive care unit (PICU) of a tertiary care hospital in northern India. Demographic, clinical, and laboratory parameters were recorded. The outcome was categorized into “survivors” and “nonsurvivors.”

Results:

The Mean (SD) age of the enrolled children [19 males (63.3%)] was 8.55 (3.07) years. Among the 30 children, 14 (46.67%) were nonsurvivors and the rest 16 (53.33%) were survivors. Nonsurvivors had ingested significantly higher doses of ALP (P < 0.001), and showed higher time lag to PICU transfer (P 0.031), presence of abnormal radiological findings on chest skiagram (P = 0.007), and a higher Pediatric Risk of Mortality (PRISM) III score (P < 0.001) at admission. Use of magnesium sulfate was associated significantly with survival [odds ratio (OR) (95% CI): 0.11 (0.02-0.66); P 0.016].

Conclusion:

The present study highlights that survival among children with ALP poisoning is predicted by dose of ALP ingestion, time lag to medical attention, and higher PRISM score at admission. Use of magnesium sulfate could be associated with better survival among them.  相似文献   
99.
100.
Febrile seizures are the most common seizures of childhood. A family history of febrile seizures is common, and the disorder is genetically heterogenous. While guidelines are available for management of simple febrile seizures, the management of complex febrile seizures is individualised. After a febrile seizure, it is important to rule out CNS infection and the decision to perform a lumbar puncture should be based on the clinical condition of the child. Neuroimaging and EEG are not required immediately in workup for simple or complex febrile seizures. Recurrence of febrile seizures may be managed at home by the parents with benzodiazepines. If the recurrences are multiple or prolonged and parents are unable to give home treatment, intermittent benzodiazepine prophylaxis may be given. Continuous antiepileptic prophylaxis may be given only to the children where intermittent prophylaxis has failed. Febrile seizures are also associated with increased risk of epilepsy, but this cannot be prevented by any form of treatment. There is also an increased risk of mesial temporal sclerosis, but whether this is an effect or cause of febrile seizures is as yet unclear. There is no increase in neurological handicaps or mortality following febrile seizures.  相似文献   
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