全文获取类型
收费全文 | 2009篇 |
免费 | 201篇 |
国内免费 | 6篇 |
专业分类
耳鼻咽喉 | 5篇 |
儿科学 | 89篇 |
妇产科学 | 32篇 |
基础医学 | 261篇 |
口腔科学 | 50篇 |
临床医学 | 167篇 |
内科学 | 422篇 |
皮肤病学 | 23篇 |
神经病学 | 101篇 |
特种医学 | 147篇 |
外科学 | 298篇 |
综合类 | 108篇 |
预防医学 | 124篇 |
眼科学 | 15篇 |
药学 | 244篇 |
肿瘤学 | 130篇 |
出版年
2022年 | 18篇 |
2021年 | 30篇 |
2020年 | 24篇 |
2019年 | 27篇 |
2018年 | 41篇 |
2017年 | 40篇 |
2016年 | 32篇 |
2015年 | 49篇 |
2014年 | 34篇 |
2013年 | 51篇 |
2012年 | 87篇 |
2011年 | 77篇 |
2010年 | 56篇 |
2009年 | 42篇 |
2008年 | 62篇 |
2007年 | 70篇 |
2006年 | 79篇 |
2005年 | 79篇 |
2004年 | 58篇 |
2003年 | 58篇 |
2002年 | 76篇 |
2001年 | 58篇 |
2000年 | 71篇 |
1999年 | 71篇 |
1998年 | 43篇 |
1997年 | 46篇 |
1996年 | 34篇 |
1995年 | 27篇 |
1994年 | 27篇 |
1993年 | 23篇 |
1992年 | 47篇 |
1991年 | 41篇 |
1990年 | 42篇 |
1989年 | 50篇 |
1988年 | 40篇 |
1987年 | 42篇 |
1986年 | 53篇 |
1985年 | 36篇 |
1984年 | 29篇 |
1983年 | 27篇 |
1982年 | 19篇 |
1981年 | 26篇 |
1980年 | 20篇 |
1979年 | 17篇 |
1978年 | 29篇 |
1976年 | 24篇 |
1975年 | 16篇 |
1974年 | 21篇 |
1972年 | 17篇 |
1971年 | 15篇 |
排序方式: 共有2216条查询结果,搜索用时 109 毫秒
1.
2.
3.
Branislav Radovancevic Alessandro Golino Bojan Vrtovec Cynthia D Thomas Rajko Radovancevic Peggy Odegaard Charles C van Rossem Sebastiaan J M Gaemers William K Vaughn Frank W Smart O H Frazier 《The Journal of heart and lung transplantation》2005,24(6):703-707
BACKGROUND: Left ventricular assist device (LVAD) support is associated with coagulopathy, bleeding, increased blood transfusion, and increased anti-HLA antibody production. Increased anti-HLA antibody production is associated with early transplant rejection, transplant coronary artery disease (CAD), and decreased post-transplant survival rates. We asked whether bridging to transplantation with an LVAD increases the risk of transplant CAD. METHODS: We reviewed data for all adults (>18 years old) who underwent heart transplantation at our institution between 1988 and 2000. After exclusion of transplant recipients who survived <3 years, we divided the remaining cohort into 2 groups: those bridged to transplantation with LVADs (mean duration of support, 149 +/- 107 days, n = 29) and those in United Network for Organ Sharing Status 1 bridged to transplantation without LVADs (controls, n = 86). We compared groups in terms of disease cause, age, sex, donor age, panel-reactive antibody testing, crossmatching, pre- and post-transplant cholesterol concentrations, diagnosis of diabetes mellitus or treated hypertension, infections, calcium channel blocker use, transplant rejection, ischemic time, cytomegalovirus infection, pre-transplant transfusion, and incidence of transplant CAD (defined as any coronary lesion identified by coronary angiography). We considered p < 0.05 to be significant. RESULTS: The bridged and control groups were similar in all respects except mean ischemic time (217 +/- 58 minutes vs 179 +/- 67 minutes, p = 0.007), post-transplant cholesterol concentration (212 +/- 55 mg/dl vs 171 +/- 66 mg/dl, p = 0.007), and pre-transplant transfusion incidence (100% vs 22%, p < 0.001). The incidence of transplant CAD was similar in both groups during a 3-year follow-up period (28% vs 17%, p = 0.238) and during total follow-up (34% vs 35%, p = 0.969). Multivariate logistic regression analysis identified cholesterol concentration at 1 year after transplantation as a significant predictor of CAD at 3 years after heart transplantation (p = 0.0029, odds ratio = 0.984). CONCLUSIONS: Bridging to transplantation with an LVAD does not increase the risk of transplant CAD. Nevertheless, aggressive prophylactic therapy to minimize potential risk factors for transplant CAD, such as increased cholesterol concentration, is warranted in all transplant recipients. 相似文献
4.
The purpose of this study is to show the spectrum of adjacent organ invasion and to make a brief review of hepatic alveolar hydatid disease (AHD), using CT and MR imaging. We retrospectively reviewed CT and MR images of three patients with various adjacent organ invasions surgically and histologically proven to be AHD. Local invasion to right kidney and adrenal, right hemidiaphragm and lung were detected in one patient, right adrenal in another patient and gall bladder, duodenum, gastric wall and pancreas invasion in the other. AHD may rarely extend to the gall bladder, stomach, duodenum, pancreas, right adrenal and kidney, diaphragm, pleura and lung. The extension of the disease outside the liver is usually encountered in patients with large, peripherally located masses in the advanced stage of the disease. 相似文献
5.
6.
A LONG PERSPECTIVE ON CHILDHOOD MULTIPLE SCLEROSIS 总被引:5,自引:1,他引:4
7.
Muscarinic suppression of the M-current in the rat sympathetic ganglion is mediated by receptors of the M1-subtype. 总被引:6,自引:1,他引:5 下载免费PDF全文
N. V. Marrion T. G. Smart S. J. Marsh D. A. Brown 《British journal of pharmacology》1989,98(2):557-573
1. Under voltage-clamp dissociated adult and foetal rat superior cervical ganglion (s.c.g.) cells exhibited a non-inactivating voltage- and time-dependent component of K+ current termed the M-current (IM). IM was detected and measured from the current decay during hyperpolarizing voltage steps applied from potentials where IM was pre-activated. 2. Neither the resting membrane current nor the amplitude of these current decay relaxations were reduced by omitting Ca from the bathing fluid, showing that the M-current was not a 'Ca-activated' K-current dependent on a primary Ca-influx. Concentrations of (+)-tubocurarine sufficient to block the slow Ca-activated K-current IAHP did not inhibit IM or antagonize the effect of muscarinic agonists on IM, showing that IM was not contaminated by IAHP. Tetraethylammonium (1 mM), which blocks the fast Ca-activated K-current IC, produced a small inhibition of IM. This was not due to contamination of IM by IC since muscarinic agonists did not consistently block IC. 3. The muscarinic agonists muscarine, oxotremorine, McN-A-343 and methacholine reversibly suppressed IM, resulting in an inward (depolarizing) current. The rank order of potency was: oxotremorine greater than or equal to muscarine greater than McN-A-343 greater than methacholine. 4. The suppression of IM by muscarine was similar in cultured cells derived from adult and foetal tissue to that seen in the intact ganglia. 5. IM-suppression by muscarine was inhibited by pirenzepine (Pz) and AF-DX 116 with mean pKB values of 7.53 +/- 0.13 (n = 3) and 6.02 +/- 0.13 (n = 4) respectively. 6. The suppression of IM by muscarinic agonists was not affected by gallamine (10-30 microM). 4-Diphenylacetoxy-N-methylpiperidine methiodide inhibited the response at 300 nM. 7. Pirenzepine inhibited the contractions of the guinea-pig isolated ileum produced by muscarine with a mean pKB of 6.37 +/- 0.03 (n = 8). 8. These results suggest that the receptors mediating suppression of the M-current accord with those designated pharmacologically as M1 and that these receptors reach maturity at a very early stage in the development of the rat s.c.g. 相似文献
8.
A synchronous occurrence of large bowel adenocarcinoma and extragenital malignant mixed mesodermal tumour (MMMT) is reported. This case represents the sixth extragenital MMMT reported in the literature. 相似文献
9.
10.
C McKenzie BAppSc P Megaw BAppSc I Morgan PhD MK Boelen PhD 《Clinical & experimental ophthalmology》1997,25(4):79-81
Deprivation of form vision by the fitting of translucent occluders suppressed the diurnal cycling of enkephalinergic amacrine cells (the ENSLI amacrine cells), in the chicken. Daily periods of normal vision or enforcing temporal contrast using strobe lighting appeared to restore normal functioning of the ENSLI cells. These results suggest that the ENSLI cells are involved in retinal circuits that assess the quality of the visual image and control eye growth. 相似文献