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   840篇
  免费   57篇
  国内免费   5篇
耳鼻咽喉   1篇
儿科学   18篇
妇产科学   13篇
基础医学   217篇
口腔科学   11篇
临床医学   49篇
内科学   285篇
皮肤病学   19篇
神经病学   34篇
特种医学   23篇
外科学   133篇
综合类   2篇
预防医学   20篇
眼科学   2篇
药学   41篇
中国医学   3篇
肿瘤学   31篇
  2023年   9篇
  2022年   11篇
  2021年   19篇
  2020年   11篇
  2019年   25篇
  2018年   16篇
  2017年   11篇
  2016年   18篇
  2015年   22篇
  2014年   16篇
  2013年   36篇
  2012年   46篇
  2011年   53篇
  2010年   32篇
  2009年   20篇
  2008年   59篇
  2007年   43篇
  2006年   30篇
  2005年   40篇
  2004年   40篇
  2003年   41篇
  2002年   44篇
  2001年   31篇
  2000年   18篇
  1999年   29篇
  1998年   9篇
  1997年   10篇
  1996年   8篇
  1995年   10篇
  1994年   6篇
  1993年   4篇
  1992年   15篇
  1991年   17篇
  1990年   16篇
  1989年   5篇
  1988年   11篇
  1987年   15篇
  1986年   9篇
  1985年   13篇
  1984年   6篇
  1983年   4篇
  1982年   2篇
  1981年   3篇
  1980年   2篇
  1979年   4篇
  1972年   1篇
  1971年   2篇
  1970年   1篇
  1969年   4篇
  1968年   3篇
排序方式: 共有902条查询结果,搜索用时 15 毫秒
1.
2.
The role of donor and recipient factors in initial renal graft non-function   总被引:1,自引:0,他引:1  
ATN is a deleterious problem in the outcome of kidney transplantation. This complication is usually related to multiple factors including donor parameters, surgical technique, ischemic time, and recipient variables. In order to develop prophylactic measures, out of 430 kidney transplants performed in our Department, a series of 90 consecutive cadaveric renal allografts has been considered in this study. The overall incidence of IGNF was 23/90 (25.5%). Kidneys from MOD revealed a lower rate of IGNF (7/35 = 20%) when compared with organs from SOD (16/55 = 29%, P = NS). No difference was noted when kidneys were removed together with heart and/or liver and/or pancreas. Out of the donor factors, only CID was significant (17 +/- 9 hours in IGNF v 11 +/- 10 hours in patients with IGF, P = less than .05). Analysis of data concerning the fate of paired kidneys revealed two cases of IGNF in both kidneys from the same donor v 14 cases of IGNF in only one of the two paired grafts (P = NS). We conclude that: 1. Donor factors are clearly associated with a minority of IGNF. 2. The introduction of multiorgan procurement programs does not complicate early function. 3. Recipient factors (immunological events and intraoperative fluid management) provides important additive effects on initial graft nonfunction.  相似文献   
3.
4.
5.
Abnormalities of tubular membrane structure and composition have been proposed as the primary defect in nephronophthisis (NEF). In order to characterize the protein composition of tubular cells in NEF, in vitro methods were developed to culture and propagate tubular cells obtained from biopsy fragments. Accordingly, microdissected cortical slices (1 x 3 mm) were first digested with collagenase and DNAse and then grown in RPMI medium supplemented with 10% NU serum and conditioned serum deriving from 3T3 cultures. At confluence, cultured cells from NEF showed characteristics which were typical of normal tubules, i.e. presence of cytokeratin and positivity for succinic dehydrogenase and alkaline phosphatase stainings, and presented no morphological alterations compared to cultured cells from normal tubular epithelium. Moreover, no difference was observed for fibronectin, collagen IV and laminin stains. Analysis by two-dimensional electrophoresis of cellular extracts revealed several changes in protein composition of NEF, the main one being the decrease in NEF cells of a polypeptide with a molecular weight of 120 kD and a pI of 4.8; this polypeptide was a constant finding in normal kidneys. These observations demonstrated that human tubular epithelial cells can be successfully cultured from very small biopsy fragments, which represents a new approach to the study of molecular disorders involving tubular cells in inherited disease. Cultured cells from NEF maintain the same morphological, immunological and cytochemical characteristics as normal tubular cells, but present a few alterations in polypeptide composition which may have pathogenetic relevance. A more careful analysis of these alterations is needed to define the molecular disorder(s) involving the tubule in NEF.  相似文献   
6.
Two-step endoscopic resection of gastric leiomyomas   总被引:2,自引:0,他引:2  
Summary Our two-step technique for endoscopic treatment of gastric leiomyomas is illustrated. From January 1979 to June 1991, nine symptomatic patients with sessile leiomyomas of the stomach were treated at the Endoscopy Division of Istituto Nazionale Tumori, Milan.The diagnosis was achieved by means of endoscopic observation of the lesion and, when possible, by ultrasound endoscopy.This new technique consists of first removing superficial portion of the tumor by electrosurgical snare. Second, a cleavage plane is found within the proper muscle layer; the tumor is enucleated as much as possible by tightening the snare around it and creating a pseudo-stalk. No major complication occurred nor were any recurrences observed at 21.8 months in the 7/9 patients treated by endoscopy alone. Endoscopic therapy was performed on an outpatient basis and only large lesions required short hospitalization.  相似文献   
7.
We have evaluated the effects of the novel immunosuppressant sodium fusidate (fusidin) in the non-obese diabetic (NOD) mouse and in D-galactosamine (D-Gal)-presensitized BALB/c mice challenged with the bacterial superantigen, Staphylococcus aureus enterotoxin B (SEB) or with the endotoxin, Escherichia coli lipopolysaccharide (LPS). The NOD mouse model has clinical and histoimmunological features similar to those of human insulin-dependent diabetes mellitus (IDDM). The SEB- and LPS-treated BALB/c mouse models exhibit pathogenic similarities with human septic shock conditions. In the NOD mouse, fusidin suppressed the spontaneous development of insulitis (mean inhibition 73%) and hyperglycaemia (IDDM incidence 25% versus 0%) when administered at 40 mg/kg five times weekly for 8 consecutive weeks from the fourth week of age; concurrently treated animals exhibited reduced percentages of splenic T lymphocytes. This anti-diabetogenic effect was confirmed in the accelerated model of diabetes induced in the NOD mouse with cyclophosphamide (CY) (IDDM incidence 55% versus 21-6% using dosages of fusidin from 40 to 80 mg/kg five times weekly); protection from IDDM development was achieved even when the drug (80 mg/kg/day) was first administered 7 days after CY challenge. In contrast, fusidin did not reverse hyperglycaemia when administered to CY-treated animals within 3 days of IDDM development. In the two models of septic shock, prophylactic treatment with fusidin, 80 mg/kg given three times for 2 days prior to D-Gal/SEB or D-Gal/LPS challenge, drastically reduced the lethality compared with D-Gal/buffer-treated mice. This effect may depend on the inhibitory action of fusidin on the secretion of cytokines such as interferon-gamma and tumour necrosis factor-alpha, the serum levels of which were greatly diminished in the fusidin-treated mice (mean inhibition 50-90%). These results demonstrate that fusidin may have a role in the treatment of cell-mediated autoimmune diseases and cytokine-mediated infectious diseases in humans.  相似文献   
8.
Partial trisomy of the long arm of chromosome 10 is a well-defined but rare syndrome. Clinical features of this chromosomopathy are a distinctive dysmorphic appearance, developmental delay, growth retardation, and in some cases, abnormalities of the extremities and renal, cardiac and ocular anomalies. This report describes a neonate with symmetric growth retardation and multiple dysmorphic features, in whom chromosomal analysis revealed a partial trisomy of chromosome 10q with a monosomy of the 13q34 region. The phenotype shares many common features with previously published cases. In addition to the typical features, our case also shows renal hypoplasia with early renal insufficiency and some genital anomalies.  相似文献   
9.
Heterogeneity of immune responsiveness in healthy elderly subjects   总被引:1,自引:0,他引:1  
We studied a group of healthy elderly subjects (satisfying the SENIEUR Protocol admission criteria), chosen as a model of age-associated immune deficiency on the basis of their reduced skin reactivity to recall antigens. Results show that aged subjects, taken as a whole, display impaired T-cell functions: reduced blastogenetic responses to mitogens, IL-2 production, responsiveness to exogenous IL-2, and percentage of Tac positive blasts. However, the age-associated immune defect shows a wide range of impairment, even in a relatively homogeneous group of anergic/hypoergic subjects. In fact, a considerable proportion of our elderly subjects displays responses comparable with those of adult controls. These observations suggest that (a) immune deficiency is not a characteristic of aging per se; (b) cutaneous delayed hypersensitivity is not a criterion sensitive enough to identify people with age-associated immune deficit; and (c) more than one test is required to evaluate T-cell impairment in aging.  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