全文获取类型
收费全文 | 3998篇 |
免费 | 284篇 |
国内免费 | 20篇 |
学科分类
医药卫生 | 4302篇 |
出版年
2021年 | 58篇 |
2020年 | 30篇 |
2019年 | 40篇 |
2018年 | 71篇 |
2017年 | 53篇 |
2016年 | 46篇 |
2015年 | 63篇 |
2014年 | 83篇 |
2013年 | 123篇 |
2012年 | 172篇 |
2011年 | 193篇 |
2010年 | 99篇 |
2009年 | 79篇 |
2008年 | 150篇 |
2007年 | 167篇 |
2006年 | 170篇 |
2005年 | 176篇 |
2004年 | 142篇 |
2003年 | 156篇 |
2002年 | 130篇 |
2001年 | 122篇 |
2000年 | 119篇 |
1999年 | 101篇 |
1998年 | 74篇 |
1997年 | 79篇 |
1996年 | 81篇 |
1995年 | 57篇 |
1994年 | 52篇 |
1993年 | 51篇 |
1992年 | 96篇 |
1991年 | 85篇 |
1990年 | 76篇 |
1989年 | 104篇 |
1988年 | 85篇 |
1987年 | 91篇 |
1986年 | 87篇 |
1985年 | 80篇 |
1984年 | 67篇 |
1983年 | 50篇 |
1982年 | 38篇 |
1981年 | 25篇 |
1980年 | 34篇 |
1979年 | 52篇 |
1978年 | 43篇 |
1977年 | 31篇 |
1976年 | 49篇 |
1975年 | 36篇 |
1974年 | 24篇 |
1973年 | 32篇 |
1972年 | 26篇 |
排序方式: 共有4302条查询结果,搜索用时 484 毫秒
51.
Immunocytochemical analysis with antibodies raised against aspartate, glutamate, gamma-aminobutyrate (GABA), choline acetyltransferase (ChAT), and substance P (SP) have allowed the transmitter characterisation and distribution of cells of the lateralis medialis-nucleus suprageniculatus (LM-SG) complex to be made at the level of the light microscope. We have found that the intranuclear distributions of aspartate and glutamate differed substantially from that of GABA, as well as there being specific and, in some cases, major differences in the respective populations of cells labelled with all three amino-acid-sensitive antibodies. ChAT-labelled elements were disposed very similarly to acetylcholinesterase (AChE)-positive subregions of the nuclear complex, while SP labelling was comparatively weak, albeit present, throughout the region. These data provide an important first step towards the further understanding of the details of the neurochemical and functional identity of the LM-SG complex. 相似文献
52.
As a further test of the hypothesis that REM deprivation decreases fear, the behavior of 40 male rats was measured in a Y-maze adapted to test for preference for novelty. Prior to this test, the animals were exposed for 4 days to one of four treatments, i.e., either a dry environment control, a wet environment control, a 2-day REM deprivation period or a 4-day REM deprivation period. During the test both number of grid crossing in the novel and non-novel arms of the Y-maze and three indices of emotionality were recorded. The results were congruent with data we had reported earlier and offered convincing evidence in support of the hypothesis. 相似文献
53.
54.
55.
A shadowing program designed to acquaint second-year pharmacy students with the professional responsibilities of a hospital pharmacist is described. The program developed by the Toledo Area Society of Hospital Pharmacists allowed second-year pharmacy students to "shadow" a staff pharmacist for three to four hours. The program required the cooperation of area hospital pharmacists to develop rotations at each site. Eight hospitals provided shadow rotations for 87 students during the program's first offering. Reactions were positive from both students and pharmacists. Direct pharmacist-student interaction, low cost, and flexibility were important factors in the program's success. The shadowing program has proven to be an effective method of introducing hospital pharmacy career options to prepharmacy students. 相似文献
56.
Duff SB Hicks GL 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》1986,13(2):233-235
Acute dissection of the aortic arch with an aberrant subclavian artery is a rare finding. This report documents the successful treatment of this unusual problem. A 56-year-old man, brought into the emergency room with severe epigastric, chest, and interscapular pain, was treated medically until stabilized. Operation was then recommended and accepted; whereupon, dissection and control of the arch vessels, including the aberrant right subclavian artery, was accomplished. At follow-up, 3 months after discharge, the patient is active, without pain, and his blood pressure is well controlled. 相似文献
57.
Rao VM; Dalinka MK; Mitchell DG; Spritzer CE; Kaplan F; August CS; Axel L; Kressel HY 《Radiology》1986,161(1):217-220
Four patients with proved osteopetrosis (three with the infantile malignant form and one with the benign form) were examined with magnetic resonance imaging at 1.5 T. All patients were studied in the coronal and sagittal planes using both short and long repetition time/echo time sequences. The infantile malignant form was characterized by a complete lack of signal from the marrow alternating with a signal intensity equivalent to that of the intervertebral disks, resulting in a "stepladder" appearance. In the benign form or after successful marrow transplantation in the infantile malignant form, intermediate or high signal intensity in the vertebrae was noted, suggesting the presence of some marrow elements. 相似文献
58.
M. Vidal P. E. Hicks S. Z. Langer 《Naunyn-Schmiedeberg's archives of pharmacology》1986,332(4):384-390
Summary The effects of ,-methylene-adenosine triphosphate, (,-methylene ATP, a P2-receptor desensitising agent) have been evaluated on vasoconstrictor responses elicited by exogenous agonists or electrical field stimulation in isolated perfused SHR or WKY tail arteries and on tritium release elicited by electrical field stimulation in SHR-tail arteries pre-labeled with 3H-noradrenaline.Exposure to ,-methylene ATP (0.1 mol/l) significantly inhibited vasoconstrictor responses to electrical field stimulation in SHR tail arteries. These inhibitory effects were not further increased at a higher concentration of ,-methylene ATP (1 mol/l). In WKY tail arteries, ,-methylene ATP (1 mol/l) failed to significantly inhibit vasoconstrictor responses to electrical stimulation.In SHR tail arteries prelabelled with 3H-noradrenaline, ,-methyleneATP (1 mol/l) did not inhibit the stimulation evoked release of tritium. However, at this concentration, ,-methylene ATP significantly antagonized the vasoconstrictor responses of SHR tail arteries induced by exogenous ATP (1 mol/l), ,-methylene ATP (30 mol/l), a stable agonist at P2-receptors, or 60 mmol/l KCl. These effects of ,-methylene ATP on contractile responses to KCl were not observed in WKY-tail arteries.In tail arteries obtained from reserpine pretreated SHR, despite a 85–95% decrease in endogenous noradrenaline tissue content, the vasoconstrictor responses induced by periarterial field stimulation were greatly diminished, but not abolished. These residual responses to periarterial field stimulation were not antagonized by prazosin (0.1 mol/l), but were practically abolished by the addition of ,-methylene ATP (1 mol/l).In tail arteries from WKY rats pretreated with reserpine, exposure to prazosin (0.1 mol/l) further reduced the residual responses elicited by electrical field stimulation. In these WKY-tail arteries, addition of ,-methylene ATP (1 mol/l) did not further inhibit the remaining vasoconstrictor response obtained in the presence of prazosin.While our results suggest a significantly greater cotransmitter role for ATP with noradrenaline in tail arteries of SHR compared with control normotensive WKY rats, additional effects of ,-methylene ATP not involving P2 receptors cannot be entirely excluded. 相似文献
59.
60.