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   7654篇
  免费   687篇
  国内免费   437篇
耳鼻咽喉   24篇
儿科学   245篇
妇产科学   64篇
基础医学   851篇
口腔科学   137篇
临床医学   956篇
内科学   1257篇
皮肤病学   112篇
神经病学   321篇
特种医学   616篇
外国民族医学   2篇
外科学   584篇
综合类   1150篇
预防医学   530篇
眼科学   178篇
药学   866篇
  7篇
中国医学   372篇
肿瘤学   506篇
  2024年   24篇
  2023年   116篇
  2022年   287篇
  2021年   359篇
  2020年   252篇
  2019年   223篇
  2018年   234篇
  2017年   207篇
  2016年   201篇
  2015年   318篇
  2014年   373篇
  2013年   382篇
  2012年   505篇
  2011年   519篇
  2010年   463篇
  2009年   399篇
  2008年   416篇
  2007年   414篇
  2006年   329篇
  2005年   295篇
  2004年   199篇
  2003年   168篇
  2002年   164篇
  2001年   127篇
  2000年   120篇
  1999年   113篇
  1998年   183篇
  1997年   203篇
  1996年   174篇
  1995年   139篇
  1994年   142篇
  1993年   118篇
  1992年   50篇
  1991年   49篇
  1990年   49篇
  1989年   64篇
  1988年   53篇
  1987年   46篇
  1986年   60篇
  1985年   49篇
  1984年   27篇
  1983年   15篇
  1982年   24篇
  1981年   30篇
  1980年   25篇
  1979年   4篇
  1978年   8篇
  1977年   18篇
  1976年   25篇
  1975年   14篇
排序方式: 共有8778条查询结果,搜索用时 11 毫秒
1.
Cutaneous plasmacytosis is a rare disorder characterized by a benign proliferation of mature plasma cells that appears as multiple dark-brown to purplish skin lesions, often associated with polyclonal hypergammaglobulinaemia. We present the case of a 55-year-old Caucasian man who suffered from a cutaneous plasmacytosis associated with two different carcinomas. Cutaneous plasmacytosis seems to be a reactive process because most cases reported are not associated with any apparent underlying disease. Nevertheless, because few reported cases were associated with malignancies, screening of additional neoplasms would be justified.  相似文献   
2.
The aim of this study was to evaluate the cerebral synthesis of eicosanoids in the asphyctic newborn and to investigate the relation between the prostanoid profiles in cerebrospinal fluid (CSF) and the appearance and severity of hypoxic-ischaemic encephalopathy (HIE). Levels of 6-keto-PGF 1-α, TXB2, PGE2 and PGF2-α in CSF were measured in 40 full term newborns during the first day of life. Thirty of these newborns had birth asphyxia and were divided into three groups: 10 without HIE, 12 with mild HIE and 8 with moderate-severe HIE. They were compared to a control group of 10 non-hypoxic newborns. Determinations of the metabolites in CSF were performed by RIA and expressed as pg/ml (mean ± SD). The CSF TXB2 (thromboxane A2 metabolite) in asphyxiated newborns was always higher than in the control group (28.12 ± 10.6), and related to the severity of HIE ( p = 0:005): without HIE (50.84 ± 16.4; p = 0:02), mild HIE (80.65 ± 12.64; p ± 0:01) and moderate-severe HIE (178.14 ± 20.5; p < 0:01). The CSF 6-keto-PGF 1-α (prostacyclin metabolite) in asphyxiated newborns was always higher than in the control group (80.55 ± 12.56), but indirectly related to the severity of HIE: without HIE (240.95 ± 28.12; p < 0:01), mild HIE (183.65 ± 30.1; p < 0:01) and moderate-severe HIE (140.55 ± 25.12; p < 0:01). In the moderate-severe HIE group, the increase in TXB2 was higher than the rise in 6-keto-PGF 1-α.  相似文献   
3.
4.
5.
6.
7.
BACKGROUND: The mainstay of treatment for pemphigus is systemic corticosteroids. Different adjuvants have been used to reduce side-effects of long-term corticotherapy. Gold is an anti-inflammatory drug used in autoimmune diseases, whose use has waned with the advent of new immunosuppressive agents. OBJECTIVE: To study the outcome of the use of intramuscular gold treatment of pemphigus vulgaris refractory to previous therapies. METHODS: Thirteen patients with pemphigus vulgaris who had failed to respond to several prior therapies were treated with aurothiomalate, as a steroid-sparing agent. Patients were monitored to assess disease activity and gold toxicity. RESULTS: Seven patients achieved complete remission. Four patients were able to taper prednisone doses, although pemphigus flared when prednisone was discontinued or reduced. Toxicity was observed in the other two patients. CONCLUSIONS: In 53.4% of the patients, the use of chrysotherapy resulted in the complete clearing of the disease, discontinuation of all systemic therapies and induced a long-term clinical remission. Prednisone doses were able to be reduced in the remaining 46.6%. Any side-effects were reversible with drug discontinuation. Gold therapy showed efficacy as a secondary line treatment in refractory pemphigus vulgaris.  相似文献   
8.
对耳轮过度前突为对耳轮的角度过锐,致使耳轮的位置相应后移,表现为与招风耳完全相反的畸形。畸形虽不十分明显,但影响美观。自1992年4月开始应用患侧耳廓软骨和耳后皮瓣对5例患者8只外耳进行治疗得到满意效果。认为文中所述方法是矫正对耳轮过度前突畸形的良好方法。  相似文献   
9.
BACKGROUND: Cyclosporin has been shown to facilitate renal vasoconstriction and to have an antinatriuretic effect. The existence of an interference of cyclosporin with the vasodilating properties of endothelium mediated by nitric oxide production could mediate these effects. On the other hand, the infusion of the nitric oxide precursor L-arginine has been shown to induce renal vasodilatation and to facilitate natriuresis in normal volunteers. We have investigated the renal effects of the administration of an infusion of L-arginine in renal transplant patients chronically treated with cyclosporin. To facilitate the analysis of the data the effects of the administration of a similar dose of cyclosporin on renal function during the infusion of a vehicle were also investigated during the administration of a vehicle of L-arginine. DESIGN: Ten male renal transplant patients, chronically treated with cyclosporin and with a stable renal function were studied during 2 consecutive days after the administration of the usual morning dose of cyclosporin. The first day they received an intravenous infusion of vehicle and the second the infusion of graded doses of L-arginine (50, 100, 150 mg/kg/h) during 3 consecutive h. RESULTS: The first day, after cyclosporin administration a significant fall (P < 0.01) was observed in natriuresis and kaliuresis in the absence of changes in renal plasma flow and glomerular filtration rate. After the administration of L-arginine significant (P < 0.01) increases of renal plasma flow, glomerular filtration rate, and natriuresis were seen. The increase in blood levels of cyclosporin after its administration did not differ between days 1 and 2. CONCLUSION: These results indicate that L-arginine facilitates renal vasodilatation and natriuresis in renal transplant patients. Furthermore, the observed increase in sodium excretion could indicate that L-arginine counteracts the antinatriuretic effect of cyclosporin.   相似文献   
10.
目的 观察血清乙酰胆碱受体抗体 (Ach Rab)含量与眼型重症肌无力患者病情程度和发展为全身型重症肌无力的关系。方法  2 0例眼型重症肌无力患者按受累程度分为轻、中、重三组 ,采用固相酶免疫吸附法测定血清 Ach Rab含量 (P/ N值 )。结果 对照组和病情轻、中、重三组血清 P/ N值分别为 :0 .6 7± 0 .45、0 .78± 0 .30、1.16± 0 .18和 1.5 1± 0 .13。轻度组与对照组比较无显著差异 (P >0 .0 5 ) ,中度组与轻度组比较差异显著 (P <0 .0 5 ) ,重度组与中度组比较有非常显著差异 (P <0 .0 1)。3例 P/ N值明显高患者 (中度组 1例、重度组 2例 ) 2年后发展成全身型。结论  P/ N值可反映患者病情程度和提供眼型重症肌无力发展为全身型重症肌无力的预兆信息。  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