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   3388篇
  免费   323篇
  国内免费   11篇
耳鼻咽喉   57篇
儿科学   67篇
妇产科学   49篇
基础医学   508篇
口腔科学   70篇
临床医学   551篇
内科学   531篇
皮肤病学   137篇
神经病学   231篇
特种医学   161篇
外科学   614篇
综合类   106篇
一般理论   1篇
预防医学   309篇
眼科学   21篇
药学   184篇
肿瘤学   125篇
  2023年   19篇
  2021年   36篇
  2020年   20篇
  2019年   45篇
  2018年   52篇
  2017年   50篇
  2016年   47篇
  2015年   28篇
  2014年   57篇
  2013年   104篇
  2012年   170篇
  2011年   160篇
  2010年   110篇
  2009年   110篇
  2008年   172篇
  2007年   163篇
  2006年   160篇
  2005年   164篇
  2004年   139篇
  2003年   161篇
  2002年   132篇
  2001年   108篇
  2000年   114篇
  1999年   109篇
  1998年   58篇
  1997年   45篇
  1996年   53篇
  1995年   38篇
  1994年   36篇
  1993年   46篇
  1992年   98篇
  1991年   72篇
  1990年   75篇
  1989年   61篇
  1988年   70篇
  1987年   59篇
  1986年   67篇
  1985年   53篇
  1984年   46篇
  1983年   40篇
  1982年   32篇
  1981年   32篇
  1980年   25篇
  1979年   44篇
  1978年   25篇
  1977年   30篇
  1976年   23篇
  1975年   19篇
  1974年   19篇
  1973年   18篇
排序方式: 共有3722条查询结果,搜索用时 140 毫秒
1.
2.
3.
This paper reports results of an open prospective study of 26 patients who met DSM-III criteria for panic disorder or agoraphobia with panic attacks. Cognitive-behavioral treatment alone produced clinically and statistically significant improvement in panic symptoms, including both full-blown and limited symptom episodes. In addition, the treatment produced improvement in associated symptoms of phobic avoidance and generalized anxiety. This work provides further preliminary indication of the usefulness of cognitive-behavioral strategies as an alternative to medication in symptom-oriented treatments.  相似文献   
4.
5.
6.
In 1995, the National League for Nursing commissioned a Panel on Interdisciplinary/Transdisciplinary Education. The focus of the Panel's work was to examine educational issues that transcend the health professions and to make recommendations for future implementation of an interdisciplinary approach to addressing them. This article is being simultaneously published by several professional journals. The goal is to seek as much feedback as possible.  相似文献   
7.
Background and Aims: Primary biliary cirrhosis (PBC) might be complicated by osteoporosis, whose etiology remains unknown but seems to be multifactorial. Prevalence rates of 30% to 60% for distal renal tubular acidosis (DRTA) have been reported in PBC patients, generally as incomplete DRTA. Although it is undisputed that a reduced bone mineral density (BMD) is the expected outcome among patients who have been suffering from longstanding chronic metabolic acidosis, it is unclear if incomplete DRTA is also associated with metabolic bone disease in PBC patients. The present study was undertaken to compare the BMD of PBC patients with and without DRTA.
Methods: The BMD of 23 PBC patients (11 with DRTA and 12 without), all with normal clearance of creatinine, was assessed by dual energy radiograph absorptiometry. The diagnosis of DRTA was made if the urine pH was above 5.4 in all samples after the oral acid overload, showing tubular inability to acidify urine in the presence of test-induced systemic metabolic acidosis.
Results: Densitometric signs of osteoporosis were found in 82% of DRTA cases and in 83% of patients without DRTA (difference not significant). There were no significant differences in BMD measurement, T and Z scores of patients with and without DRTA.
Conclusions: The present study could not support a correlation between the presence of DRTA and the bone loss observed in PBC patients.  相似文献   
8.
A case of islet cell tumor occurring in a patient with the multiple endocrine neoplasia type I syndrome is reported. Immunostaining for insulin was strongly positive in the tumor cells. Numerous dense-core granules of endocrine caliber were identified ultrastructurally. Morphometric analysis of the secretory granules in 20 islet cell tumors gave a granule size of 182 +/- 52 nm (mean +/- standard deviation).  相似文献   
9.
10.
The efficacy of various drugs used to treat ulcerative colitis, (sulfasalazine, 5-aminosalicylate, hydrocortisone) was investigated in a model of acetic acid-induced colitis in the rat. Subsequently, we tested the ability of antioxidant/5-lipoxygenase inhibitors (gossypol and nordihydroguiaretic acid [NDGA]) and a cyclooxygenase inhibitor (indomethacin) to attenuate the macroscopic colonic damage and/or neutrophil influx (myeloperoxidase activity [MPO]) associated with this model of colitis. Oral pretreatment with either sulfasalazine, gossypol, or NDGA significantly decreased colonic MPO activity induced by acetic acid. Intrarectal administration of such drugs resulted in an even larger reduction of the colonic inflammation, with gossypol being the most potent compound. Oral or intrarectal administration of corticosteroids (dexamethasone, hydrocortisone) also attenuated the parameters of acetic acid induced colitis. In contrast, pretreatment with indomethacin was ineffective, or when administered daily after colitis induction, indomethacin actually increased colonic neutrophil influx significantly. Our data suggest that both the route of drug administration and dosing regimen employed affect the antiinflammatory potency and/or efficacy of compounds on colitis induced by acetic acid in the rat. Drugs which were effective against this colitis may act by scavenging of oxygen derived free radicals.  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