全文获取类型
收费全文 | 5251篇 |
免费 | 417篇 |
国内免费 | 10篇 |
专业分类
耳鼻咽喉 | 29篇 |
儿科学 | 142篇 |
妇产科学 | 101篇 |
基础医学 | 667篇 |
口腔科学 | 38篇 |
临床医学 | 635篇 |
内科学 | 933篇 |
皮肤病学 | 85篇 |
神经病学 | 860篇 |
特种医学 | 318篇 |
外科学 | 827篇 |
综合类 | 65篇 |
一般理论 | 1篇 |
预防医学 | 269篇 |
眼科学 | 92篇 |
药学 | 335篇 |
中国医学 | 4篇 |
肿瘤学 | 277篇 |
出版年
2021年 | 55篇 |
2020年 | 42篇 |
2019年 | 58篇 |
2018年 | 79篇 |
2017年 | 69篇 |
2016年 | 83篇 |
2015年 | 96篇 |
2014年 | 100篇 |
2013年 | 139篇 |
2012年 | 217篇 |
2011年 | 201篇 |
2010年 | 134篇 |
2009年 | 152篇 |
2008年 | 233篇 |
2007年 | 251篇 |
2006年 | 230篇 |
2005年 | 251篇 |
2004年 | 209篇 |
2003年 | 238篇 |
2002年 | 224篇 |
2001年 | 216篇 |
2000年 | 189篇 |
1999年 | 160篇 |
1998年 | 49篇 |
1997年 | 48篇 |
1996年 | 51篇 |
1995年 | 58篇 |
1994年 | 39篇 |
1993年 | 53篇 |
1992年 | 101篇 |
1991年 | 104篇 |
1990年 | 111篇 |
1989年 | 107篇 |
1988年 | 94篇 |
1987年 | 91篇 |
1986年 | 86篇 |
1985年 | 118篇 |
1984年 | 79篇 |
1983年 | 68篇 |
1982年 | 46篇 |
1981年 | 42篇 |
1980年 | 34篇 |
1979年 | 74篇 |
1978年 | 45篇 |
1977年 | 51篇 |
1976年 | 44篇 |
1974年 | 57篇 |
1973年 | 49篇 |
1972年 | 38篇 |
1969年 | 34篇 |
排序方式: 共有5678条查询结果,搜索用时 15 毫秒
81.
82.
Douglas Drak Nishanta Tangirala Michael Fink Leon A. Adams Jonathan Fawcett Gary P. Jeffrey Mandy Byrne Geoffrey McCaughan Steve Chadban Kate Wyburn Germaine Wong Wai H. Lim David M. Gracey 《Transplantation proceedings》2021,53(1):136-140
AimRates of simultaneous liver and kidney transplantation (SLKT) have increased, but indications for SLKT remain poorly defined. Additional data are needed to determine which patients benefit from SLKT to best direct use of scarce donor kidneys.MethodsData were extracted from the Australia and New Zealand Dialysis and Transplant Registry (ANZDATA) database for all SLKT performed until the end of 2017. Patients were divided by pretransplant dialysis status into no dialysis before SLKT (preemptive kidney transplant) and any dialysis before SLKT (nonpreemptive). Baseline characteristics and outcomes were compared.ResultsBetween 1989 and 2017, inclusive, 84 SLKT procedures were performed in Australia, of which 24% were preemptive. Preemptive and nonpreemptive SLKT recipients did not significantly differ in age (P = .267), sex (P = .526), or ethnicity (P = .870). Over a median follow-up time of 4.5 years, preemptively transplanted patients had a statistically equivalent risk of kidney graft failure (hazard ratio (HR) 1.83, 95% confidence interval [CI]: 0.36-12.86, P = .474) and all-cause mortality (HR 1.69, 95% CI: 0.51-5.6, P = .226) compared to nonpreemptive patients. Overall, 1- and 5-year survival rates for all SLKTs were 92% (95% CI: 86-96) and 60% (95% CI: 45-75), respectively.ConclusionKidney graft and overall patient survival were similar between patients with preemptive kidney transplant and those who were dialysis dependent. 相似文献
83.
Chaperone-mediated protein folding 总被引:44,自引:0,他引:44
Fink AL 《Physiological reviews》1999,79(2):425-449
The folding of most newly synthesized proteins in the cell requires the interaction of a variety of protein cofactors known as molecular chaperones. These molecules recognize and bind to nascent polypeptide chains and partially folded intermediates of proteins, preventing their aggregation and misfolding. There are several families of chaperones; those most involved in protein folding are the 40-kDa heat shock protein (HSP40; DnaJ), 60-kDa heat shock protein (HSP60; GroEL), and 70-kDa heat shock protein (HSP70; DnaK) families. The availability of high-resolution structures has facilitated a more detailed understanding of the complex chaperone machinery and mechanisms, including the ATP-dependent reaction cycles of the GroEL and HSP70 chaperones. For both of these chaperones, the binding of ATP triggers a critical conformational change leading to release of the bound substrate protein. Whereas the main role of the HSP70/HSP40 chaperone system is to minimize aggregation of newly synthesized proteins, the HSP60 chaperones also facilitate the actual folding process by providing a secluded environment for individual folding molecules and may also promote the unfolding and refolding of misfolded intermediates. 相似文献
84.
Wilms M Eickhoff SB Specht K Amunts K Shah NJ Malikovic A Fink GR 《Anatomy and embryology》2005,210(5-6):485-495
To date, the delineation of the human visual “motion area” still relies on functional paradigms originally devised to identify
monkey area MT. Using fMRI, we have identified putative human area V5/MT+ in normals by modelling the BOLD responses to alternating radially moving and stationary dot patterns. Functional activations
were compared with cytoarchitectonic probability maps of its putative correlate area hOc5, which was calculated based upon data from histological sections of ten human post-mortem brains. Bilateral visual cortex
activations were seen in the single subject dynamic versus stationary contrasts and in the group random-effects analysis. Comparison of group data with area hOc5 revealed that 19.0%/39.5% of the right/left functional activation was assigned to the right/left hOc5. Conversely, 83.2%/53.5% of the right/left hOc5 was functionally activated. Comparison of functional probability maps (fPM) with area hOc5 showed that 28.6%/18.1% of the fPM was assigned to hOc5. In turn, 84.9%/41.5% of the area hOc5 was covered by the respective fPM. Thus, random-effects data and fPMs yielded similar results. The present study shows for
the first time the correspondence between the functionally defined human V5/MT+ and the post-mortem cytoarchitectonic area hOc5. 相似文献
85.
86.
Sexual harassment is not new to the health care industry. What is new is that recent media attention has heightened awareness that sexual harassment is illegal. This fact, coupled with the substantial liability that employers may incur if they fail to control sexual harassment, mandates the need for outlining the major issues relative to sexual harassment in today's health care setting. This article gives particular emphasis to the fact that sexual harassment can be prevented by taking a proactive stance. 相似文献
87.
Summary Rat brain cortex slices and synaptosomes preincubated with [3H]noradrenaline were used to investigate whether the NMDA-evoked noradrenaline release is modulated by agonists or antagonists at presynaptic 2-adrenoceptors.In experiments on slices, noradrenaline and the preferential 2-adrenoceptor agonists talipexole (former B-HT 920) and clonidine inhibited the NMDA evoked tritium overflow whereas the selective 1-adrenoceptor agonists cirazoline and methoxamine were ineffective. The 2-adrenoceptor antagonists rauwolscine and idazoxan facilitated the NMDA-evoked tritium overflow whereas the preferential 1-adrenoceptor antagonist prazosin was ineffective. The concentration-response curve of talipexole for its inhibitory effect on NMDA-evoked overflow was shifted to the right by idazoxan (apparent pA2 = 7.5). The EC50 of NMDA (97 mol/l) for its stimulating effect on tritium overflow was not substantially changed by blockade of 2-autoreceptors with 1 mol/l rauwolscine (EC50 of NMDA in the presence of the 2-adrenoceptor antagonist, 155 mol/l), but the maximal overflow of tritium was increased 2.5 fold by this rauwolscine concentration. In experiments on synaptosomes, talipexole and noradrenaline inhibited the NMDA-evoked tritium overflow. The inhibitory effect of talipexole was abolished by idazoxan which, given alone, was ineffective, as was prazosin. Talipexole did also not produce an inhibition when tritium overflow was evoked by NMDA in the presence of -conotoxin GVIA 0.1 mol/l; the latter, by itself, decreased the response to NMDA by about 55%. It is concluded that the NMDA-evoked noradrenaline release in the cerebral cortex is modulated via presynaptic 2-adrenoceptors on the noradrenergic neurones. Stimulation of these autoreceptors in slices by endogenous noradrenaline does not result in a decreased potency of NMDA, but in a decreased maximum effect, in stimulating noradrenaline release. The inhibitory effect of 2-adrenoceptor agonists on the NMDA-evoked release is at least partially due to a functional interaction between the NMDA receptors and 2-autoreceptors at the level of the same varicosities. The results obtained with -conotoxin GVIA suggest that Ca2+ influx via the N-type voltage-sensitive calcium channel (VSCC) occurs in response to NMDA receptor stimulation and contributes substantially to the induction of NMDA-evoked noradrenaline release. The inhibitory effect of 2-adrenoceptor stimulation on this release appears to be ultimately due to an inhibition of the influx of Ca2+ via the N-type VSCC.
Correspondence to: M. Göthert at the above address 相似文献
88.
K. Fink E. Schlicker A. Neise M. Göthert 《Naunyn-Schmiedeberg's archives of pharmacology》1990,342(5):513-519
Summary Rat brain cortex slices or synaptosomes preincubated with 3H-serotonin were superfused with physiological salt solution (which, in the case of slices, contained citalopram, an inhibitor of serotonin uptake), and the effects of histamine and related drugs on the evoked tritium overflow were studied.The electrically (3 Hz) evoked tritium overflow from slices was inhibited by histamine and the H3 receptor agonists R-(–)--methylhistamine and N-methylhistamine (pIC12.5 values: 6.41, 7.28 and 6.12, respectively), but not affected by the H1 receptor agonist 2-(2-thiazolyl)ethylamine and the H2 receptor agonist dimaprit (each at 10 mol/l). The concentration-response curve for histamine was shifted to the right by the H3 receptor antagonists impromidine, burimamide and thioperamide (apparent pA2 values: 7.45, 5.97 and 7.88, respectively); the concentration-response curve of serotonin for its inhibitory effect on the electrically evoked overflow was not affected by the three drugs (apparent pA2 values: < 5.5, < 5.5 and < 6.5). Given alone, impromidine, thioperamide and a low concentration of burimamide facilitated the electrically evoked overflow. In slices superfused with K+-rich, Ca2+-free solution containing tetrodotoxin throughout and in synaptosomes superfused with Ca2+-free solution, histamine inhibited the overflow evoked by introduction of Ca2+ (in synaptosomes, simultaneously with an increased amount of K+). In either tissue, the effect of histamine was counteracted by thioperamide.The results provide evidence that exogenous and probably also endogenous histamine inhibits serotonin release in the rat brain cortex via presynaptic histamine H3 receptors.Send offprint requests to E. Schlicker at the above address 相似文献
89.
Christine Huckstorf Johannes Zanzinger Bruno Fink Eberhard Bassenge 《Naunyn-Schmiedeberg's archives of pharmacology》1994,349(4):367-373
We investigated the relative contribution of basal and agonist stimulated EDRF/NO release to the adjustment of coronary tone and myocardial perfusion in conscious dogs by inhibiting coronary endothelial NO formation with NG-nitro-l-arginine methyl ester (l-NAME). Chronically instrumented conscious dogs (n = 9) were prepared for measurement of mean arterial blood pressure (MAP), heart rate (HR), coronary blood flow (CF) and diameter of the left circumflex (CDLC) and left anterior descending (CDLAD) coronary artery, respectively. Intracoronary infusions of l-NAME (30.3 mM; 0.25 ml × min–1) caused significant increases in MAP and decreases in HR. CDLC decreased by 3.8% from 3.01 ± 0.04 to 2.90±0.04 mm and CF decreases by 30% from 12.9 ± 0.2 to 9.1 ± 0.2 (aU). Peak reactive hyperemia (CFmax) evoked by 20-s-lasting occlusions of the left circumflex coronary artery decreased from 29.9 ± 0.8 to 25.8 ± 1.0 aU and maximal flow-dependent coronary dilation were reduced from 2.04 ± 0.08 to 0.91±0.12% after inhibition of NO-synthesis. Intracoronary infusions of acetylcholine (ACh), Adenosinc (Ado), bradykinin (Bk), and papaverine (Pap) caused dose-dependent increases in CDLC and CE Infusion of l-NAME nearly abolished the dilator effect of Ado on CDLC and reduced those to ACh, Bk and Pap. Increases in CF to ACh, Ado and Bk but not to Pap were reduced by l-NAME. Subsequent intracoronary infusions of l-arginine (303 mM; 0.25 ml × min–1) reduced l-NAME-induced CF-changes partly, but did not reverse coronary constriction. These results suggest that inhibition of the continuous release of nitric oxide markedly reduces myocardial perfusion in vivo. Endogenous dilator mechanisms are likewise impaired. Thus, in the heart, nitric oxide deficiency probably cannot be fully compensated for by counter-regulating mechanisms.
Correspondence to: E. Bassenge at the above address 相似文献
90.
J.-P. Voigt H. Fink C. A. Marsden 《Naunyn-Schmiedeberg's archives of pharmacology》1995,351(3):217-220
The present study was designed to examine possible interactions between exogenous CCK and the 5-HT1A receptor subtype mediated serotonergic effects on feeding in rats. The somatodendritic 5-HT1A receptor agonist 8-OH-DPAT (0.32 mg/kg sc) evoked feeding in freely feeding rats. This effect was attenuated by treatment with CCK-8 (1, 5 and 25 g/kg ip). In food deprived rats, CCK-8 (40 g/kg ip) significantly reduced the size of a test meal. Treatment with the 5-HT1A receptor antagonist WAY-100135 (10 mg/kg ip) antagonized this anorectic effect of CCK-8. WAY-100135 on its own did not affect food intake. These results suggest the involvement of the 5-HT1A receptor subtype in mediating 5-HT-CCK interactions in the control of food intake in rats. 相似文献