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   3711篇
  免费   333篇
  国内免费   12篇
耳鼻咽喉   14篇
儿科学   109篇
妇产科学   54篇
基础医学   506篇
口腔科学   177篇
临床医学   305篇
内科学   748篇
皮肤病学   54篇
神经病学   304篇
特种医学   96篇
外科学   592篇
综合类   143篇
一般理论   2篇
预防医学   276篇
眼科学   144篇
药学   212篇
中国医学   14篇
肿瘤学   306篇
  2023年   38篇
  2022年   57篇
  2021年   100篇
  2020年   77篇
  2019年   103篇
  2018年   123篇
  2017年   99篇
  2016年   104篇
  2015年   124篇
  2014年   131篇
  2013年   151篇
  2012年   227篇
  2011年   220篇
  2010年   146篇
  2009年   127篇
  2008年   163篇
  2007年   197篇
  2006年   174篇
  2005年   168篇
  2004年   190篇
  2003年   139篇
  2002年   151篇
  2001年   113篇
  2000年   101篇
  1999年   89篇
  1998年   41篇
  1997年   32篇
  1996年   35篇
  1995年   18篇
  1994年   32篇
  1993年   14篇
  1992年   42篇
  1991年   49篇
  1990年   60篇
  1989年   41篇
  1988年   34篇
  1987年   40篇
  1986年   41篇
  1985年   33篇
  1984年   33篇
  1983年   24篇
  1982年   14篇
  1981年   13篇
  1980年   9篇
  1979年   39篇
  1977年   16篇
  1975年   9篇
  1974年   10篇
  1972年   13篇
  1971年   9篇
排序方式: 共有4056条查询结果,搜索用时 14 毫秒
1.
2.
Clinical Rheumatology - Prof. Ari Polachek on of the author of the published version of this article missed to add his second affiliation which is the Department of Rheumatology, Tel Aviv Sourasky...  相似文献   
3.
4.
Cultured porcine thyroid cells did not reassociate into functional follicles in the presence of TSH unless the initial seeding density was adequate. At 0.2 X 10(6) cells/35 mm diameter culture dish the cells rapidly formed a monolayer even in the presence of TSH (128 microunits./ml), and radioiodide uptake was not significantly increased compared with that in control cells. Seeding densities of 1-3 X 10(6) cells/dish resulted in cultures which responded to TSH with follicular development and increased radioiodide uptake. A cell-free membrane fraction of thyroid homogenate restored the ability of cultures seeded at low densities to respond to TSH with development of follicular morphology and increased radioiodide uptake. Delaying the addition of TSH by 48 h markedly reduced the stimulation of follicular development and radioiodide uptake of cultures. Addition of membrane fractions, or an alkali-soluble fraction of membranes, at zero time improved the responses to TSH added after a 48-h delay. It was concluded that maintenance of differentiation and of TSH-responsiveness in cultured thyroid cells was influenced by cell-cell contact.  相似文献   
5.
Few studies used paired kidneys for comparison between tacrolimus and cyclosporine in renal transplantation. Most of the published data used whole blood trough levels for drug monitoring. However, the use of limited sampling strategy and abbreviated formula to estimate the 12-h area under concentration-time curve (AUC(0-12)) allowed better prediction of drug exposure. Sixty-six first cadaveric renal transplant recipients receiving paired kidneys were randomized to receive either tacrolimus-based (n = 33) or cyclosporine microemulsion (Neoral)-based therapies (n = 33). Abbreviated AUC(0-12) was used for drug monitoring and dose titration. Mean follow-up duration was 2.8 +/- 2 years. The patient and graft survival were comparable. Fewer incidence of acute rejection was observed in tacrolimus group (15% vs. 27.3%) though the difference was not significant (P = 0.23). The absolute value and the rate of decline of creatinine clearance were both significantly better in tacrolimus-treated patients. Prevalence of hypertension, post-transplant diabetes mellitus, infection, and malignancy were similar in both groups. Prevalence of hypercholesterolemia (11/33 vs. 4/33) and gum hypertrophy (6/33 vs. 1/33) was more common in cyclosporine-treated patients (P = 0.04 in both parameters). This was the first prospective, randomized study with paired kidney analysis showing the renal function was significantly better in tacrolimus-treated patients than in cyclosporine-treated patients.  相似文献   
6.
7.
8.
We measured CBF and the CMRglc in normal controls and in patients with severe liver disease and evidence for minimal hepatic encephalopathy using positron emission tomography. Regions were defined in frontal, temporal, parietal, and visual cortex; the thalamus; the caudate; the cerebellum; and the white matter along with a whole-slice value obtained at the level of the thalamus. There was no difference in whole-slice CBF and CMRglc values. Individual regional values were normalized to the whole-slice value and subjected to a two-way repeated measures analysis of variance. When normalized CBF and CMRglc values for regions were compared between groups, significant differences were demonstrated (F = 5.650, p = 0.00014 and F = 4.58, p = 0.0073, respectively). These pattern differences were due to higher CBF and CMRglc in the cerebellum, thalamus, and caudate in patients and lower values in the cortex. Standardized coefficients extracted from a discriminant function analysis permitted correct group assignment for 95.5% of the CBF studies and for 92.9% of the CMRglc studies. The similarity of the altered pattern of cerebral metabolism and flow in our patients to that seen in rats subjected to portacaval shunts or ammonia infusions suggests that this toxin may alter flow and metabolism and that this, in turn, causes the clinical expression of encephalopathy.  相似文献   
9.
The effects of introduction of a low steroid regime and pre-transplant blood transfusion were evaluated. The kidney and patient survival rates for the period before such a policy was adopted were compared with the period after this policy. There has been a highly significant rise in patient survival rates to the present level of 95 per cent at three years. There was a similar rise in three year graft survival rates from less than 40 per cent to 66 per cent.  相似文献   
10.
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