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   420篇
  免费   24篇
  国内免费   6篇
儿科学   29篇
妇产科学   3篇
基础医学   45篇
口腔科学   7篇
临床医学   32篇
内科学   98篇
皮肤病学   5篇
神经病学   7篇
特种医学   85篇
外科学   50篇
综合类   7篇
预防医学   25篇
眼科学   6篇
药学   32篇
肿瘤学   19篇
  2022年   1篇
  2021年   2篇
  2020年   1篇
  2019年   3篇
  2018年   8篇
  2017年   5篇
  2016年   7篇
  2015年   9篇
  2014年   4篇
  2013年   19篇
  2012年   8篇
  2011年   5篇
  2010年   16篇
  2009年   18篇
  2008年   11篇
  2007年   12篇
  2006年   11篇
  2005年   12篇
  2004年   5篇
  2003年   8篇
  2002年   10篇
  2001年   5篇
  2000年   1篇
  1999年   9篇
  1998年   26篇
  1997年   28篇
  1996年   30篇
  1995年   22篇
  1994年   25篇
  1993年   18篇
  1992年   9篇
  1991年   3篇
  1990年   7篇
  1989年   13篇
  1988年   6篇
  1987年   9篇
  1986年   10篇
  1985年   5篇
  1984年   4篇
  1983年   4篇
  1982年   4篇
  1981年   9篇
  1980年   7篇
  1979年   2篇
  1978年   2篇
  1977年   4篇
  1976年   10篇
  1975年   3篇
排序方式: 共有450条查询结果,搜索用时 0 毫秒
441.
目的 探讨瘢痕子宫再次妊娠的分娩方式。方法 对199例瘢痕子宫再次妊娠分娩方式资料进行统计分析。结果 199例瘢痕子宫再次妊娠分娩者中158例剖宫产,剖宫产率达79.4%(73.7%~85.2%)。其原因有社会因素、胎儿窘迫、产科并发症等,而真正由于瘢痕原因需要再次剖宫产者仅10例。只占5.03%(1.99%~8.06%)。结论 瘢痕子宫再次妊娠.分娩方式仍可以选择阴道试产,在掌握好阴道分娩指征、严密监护、病人配合和家属理解的情况下。是可以经阴道分娩的。  相似文献   
442.
We conducted an audit of paediatric trauma admissions to QECH, Blantyre, in September 2003. There were 107 trauma cases representing 8.8% of all paediatric admissions and mean age was 6 years. The commonest cause of trauma was falls (42.9%) followed by burns (31.8%) and road traffic accidents (14.9%). Of the road traffic accidents, only one case was a passenger, the rest were pedestrians hit by moving vehicles. Fracture of limbs was the commonest injury sustained (44.9%) and burns the second commonest injury (31.8%). Most (52.6%) children were brought into hospital within 24 hours of injury while 26.3% came in between 24 hours and 48 hours and 21.1% after 48 hours or more. Death occurred in 7.5% of cases. The mean number of days in hospital was 8.9 days.  相似文献   
443.

Background and Purpose

Anti-complement therapies have not been advanced for treating the inflammatory bowel diseases (IBDs) despite a growing body of evidence that blocking C5a protects against induced colitis in rodents. The purpose of this study was to further build on this evidence by examining the efficacy, mechanism and specificity of a potent, non-competitive and orally active C5a receptor (CD88) antagonist, PMX205, in the dextran sulphate sodium (DSS) model of murine innate colitis.

Experimental Approach

Mice with DSS added to their drinking water were orally administered 100 or 200 μg day−1 PMX205 in prophylactic and therapeutic regimens. Clinical illness, colon histology and local generation of inflammatory mediators were measured to evaluate the impact of PMX205 on disease.

Key Results

PMX205 significantly prevented DSS-induced colon inflammation in both regimens, associated with lower pro-inflammatory cytokine production and nitrotyrosine staining in colon sections. Additionally, the levels of anti-inflammatory cytokines IL-4 and IL-10 were increased. PMX205 had no significant effect on C5a levels. The beneficial effect of PMX205 was seen in two strains of mice of differing sensitivities to DSS inflammation, but was inactive in mice lacking CD88.

Conclusions and Implications

Pharmacological inhibition of C5a activity by PMX205 is efficacious in preventing DSS-induced colitis, providing further evidence that targeting CD88 in IBD patients could be a valuable therapeutic option.  相似文献   
444.
445.

Objectives

Non-human primates are immunologically closely related to humans providing relevant models of inflammatory disorders often used to evaluate new immunomodulating therapies. The aim of the study was to compare inflammatory infiltrates of acute graft rejection (AR) and collagen-induced arthritis (CIA) to delayed-type hypersensitivity (DTH) reactions as the latter model may serve as a less invasive animal model.

Materials and methods

Tissue samples of AR, CIA and DTH were obtained from rhesus monkeys used in several pre-clinical studies. The infiltrate composition was determined by immunohistochemical analysis.

Results

The infiltrates in AR consisted of T cells, macrophages and B cells. The presence of lymphoid structures in AR suggested ongoing intragraft immune activation. The synovia of CIA contained predominantly macrophages and few T cells. The DTH infiltrates were dominated by T cells when the challenged was ovalbumin (OVA) and by macrophages when the challenge was tetanus toxoid (TT).

Conclusions

The histology of AR resembles aspects of DTH to OVA while that of CIA showed similarities of the DTH to TT. The DTH reaction could serve as a model to study immunomodulating drugs for acute rejection and the acute inflammatory phase of autoimmunity.  相似文献   
446.
447.
Trisomy 3 in low-grade B-cell lymphomas of mucosa-associated lymphoid tissue   总被引:13,自引:3,他引:13  
Wotherspoon  AC; Finn  TM; Isaacson  PG 《Blood》1995,85(8):2000-2004
Characteristic chromosomal aberrations have been associated with subtypes of non-Hodgkin's lymphoma with distinct clinicopathologic features. Low-grade B-cell lymphomas of mucosa-associated lymphoid tissue (MALT) form such a group and might be expected to be characterized by a specific cytogenetic abnormality. Metaphase analyses of MALT lymphoma are rare due to problems with fresh tissue collection and poor in vitro proliferation. However, the small number of published series suggests that chromosome trisomies, particularly trisomy 3, might be characteristic of these tumors. The application of interphase cytogenetic techniques to routinely processed material allows the examination of a large series of archival cases and is particularly useful for the demonstration of chromosome trisomies. We have used this technique to analyze 70 cases of low-grade MALT lymphoma from various sites and found trisomy 3 in 60%. This finding compares with 16% in low- grade nodal B-cell lymphoma and 27% in primary splenic lymphoma of marginal zone type (splenic lymphoma with villous lymphocytes). These results provide further evidence that low-grade MALT lymphomas from all sites form a single pathologic entity distinct from nodal B-cell lymphomas. Although MALT lymphoma and primary splenic lymphoma may arise from marginal zone B cells, they are genetically distinct.  相似文献   
448.
ObjectiveTo document movement patterns, home range, nesting behaviour and social organization of 5 individuals (3 males and 2 females) of a common species of tree-shrew, Tupaia glis (T. glis) surrounding houses of otoacariasis cases.MethodsEach shrew was fitted with a transmitter chip radio-collar which operates between the frequencies of 154.13 MHz to 154.21 MHz. Each transmitter was then tracked with a Portable Telemetry Receiver (Sirtrack, New Zealand) fitted with a 3-element Yagi antenna. Collared shrews were located using standard methods of ground-based triangulation. Each location was taken from at least 2 directional fixes and a minimum of 3 compass bearings. Fixes were taken hourly for each collared individual from the time of emergence from nest (beginning of activity) till time of entry into the nest (end of activity) every day for 5 to 7 continuous days. Three series of radio telemetry observations were carried out. The bearings, time and positions of an observer were recorded and later plotted on a graph paper in order to derive coordinates of the collared animal. [These coordinates then analyzed using Ecological Software Solutions (Biotas Version 1.03)].ResultsNests were found in a jack fruit tree, long bushes, and 2 houses. Daily telemetry detections demonstrated 2 individuals of different sex having nests (or a nest) in the same house. All shrews emerged from and returned to their nests between 0601 to 0659 hours and 1901 to 1959 hours, respectively. Both the time of exit from and entry into nest were the same between sexes (P>0.05). Their average total active period was 4.90 to 7.00 hours with a total daily travel distant of 270 m to 382 m. A male and a female shrew can move as far as 3 285 m and 4 591 m, respectively. Active movements of T. glis were during daytime. They regularly entered some houses in the area during day and night except for one individual which visited during daytime only. The sizes of home range and core area for the shrews were 2.00–3.40 ha and 0.05–0.42 ha, respectively. Generally, the mean home range size of females was 20.8% larger than that of males. Females covered a 15.4% slightly higher daily movement range compared to males.ConclusionsThis is the first radio telemetry study in Malaysia to monitor movements and home range of shrews carrying ticks on their body. It demonstrates that shrews are potential carriers of ticks from wild into the houses and their compounds based on their total active periods spent moving around from fruit orchards, secondary forest, plantations and other vegetations to trees in compound of 4 to 7 houses and vice versa. There are also evidences showing shrews have close contact with humans.  相似文献   
449.

Background and purpose:

Glucocorticoids are highly effective in the therapy of inflammatory diseases. Their value, however, is limited by side effects. The discovery of the molecular mechanisms of the glucocorticoid receptor and the recognition that activation and repression of gene expression could be addressed separately opened the possibility of achieving improved safety profiles by the identification of ligands that predominantly induce repression. Here we report on ZK 245186, a novel, non-steroidal, low-molecular-weight, glucocorticoid receptor-selective agonist for the topical treatment of inflammatory dermatoses.

Experimental approach:

Pharmacological properties of ZK 245186 and reference compounds were studied in terms of their potential anti-inflammatory and side effects in functional bioassays in vitro and in rodent models in vivo.

Key results:

Anti-inflammatory activity of ZK 245186 was demonstrated in in vitro assays for inhibition of cytokine secretion and T cell proliferation. In vivo, using irritant contact dermatitis and T cell-mediated contact allergy models in mice and rats, ZK 245186 showed anti-inflammatory efficacy after topical application similar to the classical glucocorticoids, mometasone furoate and methylprednisolone aceponate. ZK 245186, however, exhibits a better safety profile with regard to growth inhibition and induction of skin atrophy after long-term topical application, thymocyte apoptosis, hyperglycaemia and hepatic tyrosine aminotransferase activity.

Conclusions and implications:

ZK 245186 is a potent anti-inflammatory compound with a lower potential for side effects, compared with classical glucocorticoids. It represents a promising drug candidate and is currently in clinical trials.This article is part of a themed issue on Mediators and Receptors in the Resolution of Inflammation. To view this issue visit http://www3.interscience.wiley.com/journal/121548564/issueyear?year=2009  相似文献   
450.
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