全文获取类型
收费全文 | 825篇 |
免费 | 83篇 |
国内免费 | 8篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 31篇 |
妇产科学 | 15篇 |
基础医学 | 122篇 |
口腔科学 | 42篇 |
临床医学 | 72篇 |
内科学 | 312篇 |
皮肤病学 | 11篇 |
神经病学 | 36篇 |
特种医学 | 73篇 |
外科学 | 56篇 |
综合类 | 18篇 |
预防医学 | 43篇 |
眼科学 | 5篇 |
药学 | 41篇 |
中国医学 | 15篇 |
肿瘤学 | 23篇 |
出版年
2022年 | 5篇 |
2019年 | 6篇 |
2018年 | 5篇 |
2016年 | 5篇 |
2015年 | 12篇 |
2014年 | 7篇 |
2013年 | 22篇 |
2012年 | 15篇 |
2011年 | 16篇 |
2010年 | 28篇 |
2009年 | 21篇 |
2008年 | 23篇 |
2007年 | 28篇 |
2006年 | 21篇 |
2005年 | 11篇 |
2004年 | 11篇 |
2003年 | 13篇 |
2002年 | 13篇 |
2001年 | 13篇 |
2000年 | 14篇 |
1999年 | 24篇 |
1998年 | 22篇 |
1997年 | 45篇 |
1996年 | 34篇 |
1995年 | 26篇 |
1994年 | 26篇 |
1993年 | 31篇 |
1992年 | 29篇 |
1991年 | 23篇 |
1990年 | 30篇 |
1989年 | 29篇 |
1988年 | 24篇 |
1987年 | 31篇 |
1986年 | 27篇 |
1985年 | 29篇 |
1984年 | 19篇 |
1983年 | 28篇 |
1982年 | 26篇 |
1981年 | 23篇 |
1980年 | 14篇 |
1979年 | 8篇 |
1978年 | 8篇 |
1976年 | 4篇 |
1975年 | 7篇 |
1974年 | 11篇 |
1973年 | 5篇 |
1972年 | 4篇 |
1971年 | 5篇 |
1970年 | 7篇 |
1969年 | 5篇 |
排序方式: 共有916条查询结果,搜索用时 15 毫秒
1.
Summary— KR31080 (2-butyl-5-methyl-6-(1-oxopyridin-2-yl)-3-[[2'-(1H-tetrazol-5-yl) biphenyl-4-yl]methyl]-3H-imidazo[4,5-b] pyridine) is a potent inhibitor of angiotensin type 1 (AT1 ) receptors in rabbit aorta and human recombinant AT1 receptors. In the isolated rabbit thoracic aorta, KR31080 caused a nonparallel shift to the right of the concentration-response curves to angiotensin II (All) with decreased maximal response (pD'2 = 10.1 ± 0.1), but had no effect on the contractile response induced by norepinephrine. KR31080 inhibited specific [125 I]AII binding to rabbit aortic membranes (AT, receptors) and [125 I][Sar1 , Ile8 ]AII binding to human recombinant AT1 receptors in a concentration-dependent manner with IC50 values of 0.84 ± 0.08 nM and 1.92 ± 0.15 nM, respectively, but did not inhibit specific [125 I)AII binding to bovine cerebellum membranes (ÀT2 receptors). In the Scatchard analysis, KR31080 interacted with rabbit aortic AT1 receptors in a competitive manner, similar to losartan. These results demonstrate that KR31080 is a potent and AT1 selective angiotensin receptor antagonist which exerts a competitive antagonism in the [125 I]AII binding assay and insurmountable AT1 receptor antagonism in the functional study. 相似文献
2.
3.
4.
SUMMARY Elevated plasma levels of Lp(a) do seem to influence the progression of atherosclerosis. Evidence is emerging that certain apo(a) isoforms may be more atherogenic than others, and in transgenic mice free apo(a) has been shown to be associated with accelerated atherosclerosis. Currently it is not known whether treating elevated Lp(a) levels will reduce progression of atherosclerosis and, as therapeutic options are limited, mass screening of Lp(a) levels in populations is not indicated. The presence of raised Lp(a) levels, however, warrants aggressive treatment to reduce other cardiovascular risk factors. Continuing research to investigate the relationship of the apo(a) gene to other genes, including the plasminogen gene and apo(a)-related genes, will add further information pertaining to the evolution, function, regulation and clinical implications of Lp(a). 相似文献
5.
6.
Virological, biochemical and histological effects of human lymphoblastoid interferon in Swedish patients with chronic hepatitis C 总被引:1,自引:0,他引:1
J. A. Garson I. Uhnoo K. Whitby J. H. Braconier R. Deaville A. Duberg E. Wallmark J. Wiström R. D. Goldin B. Spacey 《Journal of viral hepatitis》1997,4(5):325-331
Thirty-eight Swedish patients with chronic hepatitis C were randomly assigned to receive either 3 million units (MU) or 5MU of human lymphoblastoid interferon-α-n1 (Wellferon) three times per week for either 6 or 12 months. The patients were monitored biochemically, histologically and by quantitative polymerase chain reaction for circulating HCV RNA, during therapy and for the following year. Overall, 22 (58%) of the patients lost detectable hepatitis C virus (HCV) viraemia during therapy but eight of these patients relapsed during follow-up, leaving 14 (37%) sustained responders. Patients infected with HCV non-type 1 genotypes were significantly more likely to achieve a sustained response than were those infected with HCV type 1 (63% vs 10.5%, P =0.001). Sustained virological responses were also associated with lower pretreatment viraemia level, younger age, absence of cirrhosis and the higher interferon dosage regimens but these associations failed to reach statistical significance. In 97% of patients there was concordance between virological and biochemical responses, and a statistically significant ( P =0.005) improvement in the Knodell histological activity index was observed in the virological sustained responders. 相似文献
7.
8.
J A Garson M Lenzi C Ring F Cassani G Ballardini M Briggs R S Tedder F B Bianchi 《Journal of medical virology》1991,34(4):223-226
Sera from 14 patients with type 2 autoimmune hepatitis (anti-LKM1 positive) were investigated for evidence of hepatitis C virus (HCV) infection. Antibodies to HCV were detected in 13 patients by both commercial and "in-house" ELISAs and also by a second generation recombinant immunoblot assay. Nine of the 13 (69%) anti-HCV positive patients were shown to be viraemic by a polymerase chain reaction-based assay for serum HCV RNA. Neither anti-HCV nor serum HCV RNA were detected in any of 6 controls with primary biliary cirrhosis or in 39 healthy blood donors. These findings strongly suggest a role for HCV in the pathogenesis of type 2 autoimmune hepatitis. 相似文献
9.
The authors describe the implementation and development of an incentive plan to improve professional fee collections at an indigent-care teaching hospital. They theorized that an incentive plan based on relative value unit (RVU) productivity would increase billings and collections of professional fees. Unique RVU targets were set for individual services based on the number of faculty full-time equivalents and average reported productivity for academic physicians by specialty. The incentive plan was based on the level of expected faculty billings, measured in RVUs, for each department. A "base + incentive" model was used, with the base budget being distributed monthly throughout the year, and the incentive held as a "withhold" to be paid at the year's end only if the billing target in RVUs was met. Additionally, a task force worked with physician billing office and the hospital to improve collections. In the first year after implementation of the system was in place, important increases were noted in total RVU productivity (30.5% over the previous year) and in collections (49.5% over the previous year). Sixteen of 23 departments exceeded their incentive targets, and it was possible to make distributions of professional fees to those departments, to be used within the hospital system to enhance clinical services. Moreover, the plan created an overall positive attitude toward billings and documentation of faculty activities. The authors believe that this kind of incentive plan will be increasingly important for academic faculty working in public hospital systems. 相似文献
10.
Detection of chromosomes and estimation of aneuploidy in human spermatozoa using fluorescence in-situ hybridization 总被引:11,自引:0,他引:11
The development and application of fluorescence in-situ hybridization
(FISH) has opened the way for comprehensive studies on numerical chromosome
abnormalities in human spermatozoa. FISH can be rapidly applied to large
numbers of spermatozoa and thus overcomes the major limitation of
karyotyping spermatozoa after penetration of zona-free hamster oocytes. The
simultaneous hybridization of two or more chromosome-specific probes to
spermatozoa and subsequent detection of the bound probes using different
fluorescent detection systems enables two or more chromosomes to be
localized simultaneously in the same spermatozoon and provides a technique
for undertaking reasonable estimates of aneuploidy. The most commonly used
probes are those which bind to the centromeric region of specific
chromosomes. Most studies to date have concentrated on estimating
aneuploidy in spermatozoa from normospermic men, although reports are
beginning to appear on aneuploidy in spermatozoa from subfertile and
infertile men. Multi- probe FISH studies have generally reported disomy
(hyperhaploidy) estimates of 0.05-0.2% per chromosome. There is preliminary
evidence that some chromosomes such as X, Y and 21 are predisposed towards
higher rates of non-disjunction during spermatogenesis. There are also
suggestions of inter-donor variability in aneuploidy frequencies for
specific chromosomes, although this requires confirmation in larger
studies. While FISH is clearly a powerful technique that has many
applications in reproductive medicine, it must also be realized that it
does have limitations and the technology itself is still evolving and has
yet to be fully validated on spermatozoa.
相似文献