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   7973篇
  免费   760篇
  国内免费   78篇
耳鼻咽喉   66篇
儿科学   442篇
妇产科学   97篇
基础医学   949篇
口腔科学   174篇
临床医学   818篇
内科学   1631篇
皮肤病学   428篇
神经病学   500篇
特种医学   608篇
外科学   1026篇
综合类   204篇
一般理论   8篇
预防医学   574篇
眼科学   59篇
药学   492篇
  2篇
中国医学   3篇
肿瘤学   730篇
  2021年   78篇
  2019年   87篇
  2018年   109篇
  2017年   77篇
  2016年   93篇
  2015年   110篇
  2014年   136篇
  2013年   192篇
  2012年   226篇
  2011年   226篇
  2010年   219篇
  2009年   205篇
  2008年   269篇
  2007年   313篇
  2006年   291篇
  2005年   285篇
  2004年   241篇
  2003年   242篇
  2002年   208篇
  2001年   230篇
  2000年   244篇
  1999年   227篇
  1998年   196篇
  1997年   225篇
  1996年   208篇
  1995年   184篇
  1994年   169篇
  1993年   146篇
  1992年   172篇
  1991年   215篇
  1990年   198篇
  1989年   189篇
  1988年   218篇
  1987年   198篇
  1986年   178篇
  1985年   213篇
  1984年   132篇
  1983年   128篇
  1982年   86篇
  1981年   90篇
  1980年   75篇
  1979年   111篇
  1978年   105篇
  1977年   87篇
  1976年   93篇
  1975年   80篇
  1974年   93篇
  1973年   100篇
  1972年   72篇
  1971年   72篇
排序方式: 共有8811条查询结果,搜索用时 0 毫秒
31.
Between March 1985 and December 1991, mediastinitis developed in 12 of 420 cardiac transplantation patients (2.8%). The mortality rate in this group of patients was 8.3% (1/12). Actuarial survival (1 year, 75%; and 5 years, 65%) was not significantly different from that of the group without mediastinitis (1 year, 88%; and 5 years, 75%). A higher percentage of the patients in the group with mediastinitis were listed as UNOS status 1 (50% versus 35%) and had a history of previous sternotomies (58% versus 44%). The presentation of mediastinitis was typical. Computed tomographic scanning with or without aspiration was a valuable adjunct in the diagnosis of mediastinitis. Induction immunotherapy with minimal steroids in the perioperative period was used in all patients. This may contribute to the patients' ability to mount an appropriate and effective response to infection, permitting earlier diagnosis. The debridement irrigation technique used in 8 of 12 patients had a low success rate of 33%, whereas the debridement muscle flap technique used in 4 of 12 was 100% successful in eliminating infection.  相似文献   
32.
33.
34.
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   
35.
OBJECTIVE: Telepsychiatry in the form of videoconferencing brings enormous opportunities for clinical care, education, research, and administration. Focusing on videoconferencing, we reviewed the telepsychiatry literature and compared telepsychiatry with services delivered in person or through other technologies. METHODS: We conducted a comprehensive review of telepsychiatry literature from January 1, 1965, to July 31, 2003, using the terms telepsychiatry, telemedicine, videoconferencing, effectiveness, efficacy, access, outcomes, satisfaction, quality of care, education, empowerment, and costs. We selected studies for review if they discussed videoconferencing for clinical and educational applications. RESULTS: Telepsychiatry is successfully used for various clinical services and educational initiatives. Telepsychiatry is feasible, increases access to care, enables specialty consultation, yields positive outcomes, allows reliable evaluation, has few negative aspects in terms of communication, generally satisfies patients and providers, facilitates education, and empowers parties using it. Data are limited with regard to clinical outcomes and cost-effectiveness. CONCLUSIONS: Telepsychiatry is effective. More short- and long-term quantitative and qualitative research is warranted on clinical outcomes, predictors of satisfaction, costs, and educational outcomes.  相似文献   
36.
37.
38.
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   
39.
40.
Although benign, pituitary adenomas may not always be curable by surgery alone. This is usually owing to dural infiltration and the technical problems of removal of involved dura in the sellar region. In such circumstances, some form of adjuvant therapy may be needed to address residual tumour and forestall recurrence. Radiotherapy and drugs, such as bromocriptine or octreotide, although effective are far from ideal adjuvant therapies and this has led to the study of the effects of photodynamic therapy on pituitary adenomas. It has been shown that photodynamic therapy using the photosensitising drugs haematoporphyrin derivative and aluminium phthalocyanine is active experimentally against these tumours. This could provide another useful weapon to use against these challenging lesions.  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