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   1080篇
  免费   59篇
  国内免费   36篇
耳鼻咽喉   5篇
儿科学   70篇
妇产科学   6篇
基础医学   111篇
口腔科学   32篇
临床医学   135篇
内科学   246篇
皮肤病学   23篇
神经病学   56篇
特种医学   184篇
外科学   76篇
综合类   24篇
预防医学   78篇
眼科学   16篇
药学   72篇
中国医学   1篇
肿瘤学   40篇
  2023年   2篇
  2022年   6篇
  2021年   17篇
  2020年   9篇
  2019年   11篇
  2018年   26篇
  2017年   23篇
  2016年   15篇
  2015年   21篇
  2014年   20篇
  2013年   46篇
  2012年   36篇
  2011年   36篇
  2010年   54篇
  2009年   44篇
  2008年   35篇
  2007年   37篇
  2006年   31篇
  2005年   39篇
  2004年   19篇
  2003年   19篇
  2002年   21篇
  2001年   23篇
  2000年   16篇
  1999年   30篇
  1998年   52篇
  1997年   46篇
  1996年   52篇
  1995年   33篇
  1994年   41篇
  1993年   35篇
  1992年   23篇
  1991年   22篇
  1990年   13篇
  1989年   29篇
  1988年   46篇
  1987年   24篇
  1986年   21篇
  1985年   29篇
  1984年   11篇
  1983年   4篇
  1982年   6篇
  1981年   8篇
  1980年   8篇
  1979年   5篇
  1978年   5篇
  1977年   6篇
  1976年   12篇
  1975年   3篇
  1971年   2篇
排序方式: 共有1175条查询结果,搜索用时 15 毫秒
31.
Abstract

Cerebrospinal fluid (CSFJ and serum levels of transforming growth factor (TGFJ-f3 and soluble intercellular adhesion molecule-1 (sICAM-l) were evaluated in ten patients with definite multiple sclerosis (MS) of the relapsing-remitting type. CSF TGF-β levels of MS patients in remission were significantly (p < 0.01) higher than of MS patients in active phase and there was a significant inverse correlation (p < 0.05) between TGF-β and sICAM-l levels in the CSF of patients in both remitting and relapsing type. This is consistent with a possible down-regulation of TGF-β on ICAM-l expression and suggests a possible synthesis in the central nervous system of TGF-β. [Neural Res 1997; 19: 599-600]  相似文献   
32.
Cortical bone porosity is intimately linked with remodeling, is of growing clinical interest, and is increasingly accessible by imaging. Thus, the potential of animal models of osteoporosis (OP) to provide a platform for studying how porosity develops and responds to interventions is tremendous. To date, rabbit models of OP have largely focused on trabecular microarchitecture or bone density; some such as ovariectomy (OVX) have uncertain efficacy and cortical porosity has not been extensively reported. Our primary objective was to characterize tibial cortical porosity in rabbit-based models of OP, including OVX, glucocorticoids (GC), and OVX + GC relative to controls (SHAM). We sought to: (i) test the hypothesis that intracortical remodeling is elevated in these models; (ii) contrast cortical remodeling and porosity in these models with that induced by parathyroid hormone (1–34; PTH); and (iii) contrast trabecular morphology in the proximal tibia across all groups. Evidence that an increase in cortical porosity occurred in all groups was observed, although this was the least robust for GC. Histomorphometric measures supported the hypothesis that remodeling rate was elevated in all groups and also revealed evidence of uncoupling of bone resorption and formation in the GC and OVX + GC groups. For trabecular bone, a pattern of loss was observed for OVX, GC, and OVX + GC groups, whereas the opposite was observed for PTH. Change in trabecular number best explained these patterns. Taken together, the findings indicated rabbit models provide a viable and varied platform for the study of OP and associated changes in cortical remodeling and porosity. Intriguingly, the evidence revealed differing effects on the cortical and trabecular envelopes for the PTH model. © 2020 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR)..  相似文献   
33.
34.
35.
Abstract:  The study of plasma integrates physics, chemistry, biology, and engineering, and has recently engaged medicine and dental hygiene in research efforts. The study of plasma holds promise for a myriad of applications ranging from lasers and electronics, hazardous waste management, decontamination, sterilization and disinfection of foods, soil, water, instruments, to medical uses in wound healing and treating certain types of tumours and cancers. Plasma represents a new state-of-the-art sterilization and disinfection treatment for certain oral and enviornmental pathogens, heat-sensitive materials, contaminated medical waste, hard and soft surfaces, and ventilation systems may assist health care facilities in the management of various health concerns. The role that Low Temperature Atmospheric Pressure Plasma (LTAPP) could play in the inactivation of pathogenic microorganisms might prove to be a new, faster, noncorrosive, more economical alternative, as well as support green healthcare.  相似文献   
36.
37.
38.
Aggressive periodontitis (AgP) is a multifactorial disease. The distinctive aspect of periodontitis is that this disease must deal with a large number of genes interacting with one another and forming complex networks. Thus, it is reasonable to expect that gene-gene interaction may have a crucial role. Therefore, we carried out a pilot case-control study to identify the association of candidate epistatic interactions between genetic risk factors and susceptibility to AgP, by using both conventional parametric analyses and a higher order interactions model, based on the nonparametric Multifactor Dimensionality Reduction algorithm. We analyzed 122 AgP patients and 246 appropriate periodontally healthy individuals, and genotyped 28 polymorphisms, located within 14 candidate genes, chosen among the principal genetic variants pointed out from literature and having a role in inflammation and immunity. Our analyses provided significant evidence for gene--gene interactions in the development of AgP, in particular, present results: (a) indicate a possible role of two new polymorphisms, within SEPS1 and TNFRSF1B genes, in determining host individual susceptibility to AgP; (b) confirm the potential association between of IL-6 and Fc γ- receptor polymorphisms and the disease; (c) exclude an essential contribution of IL-1 cluster gene polymorphisms to AgP in our Caucasian-Italian population.  相似文献   
39.
Background Heart failure (HF) is a physically and socially debilitating disease that carries the burden of hospital re-admission and mortality. As an aging society, Hong Kong urgently needs to find ways to reduce the hospital readmission of HF patients. This study evaluates the effects of a nurse-led HF clinic on the hospital readmission and mortality rates among older HF patients in Hong Kong. Methods This study is a retrospective data analysis that compares HF patient in a nurse-led HF clinic in Hong Kong compared with HF patients who did not attend the clinic. The nurses of this clinic provide education on lifestyle modification and symptom monitoring, as well as titrate the medications and measure biochemical markers by following established protocols. This analysis used the socio-demographic and clinical data of HF patients who were aged ≥ 65 years old and stayed in the clinic over a six-month period. Results The data of a total of 78 HF patients were included in this data analysis. The mean age of the patients was 77.38 ± 6.80 years. Approximately half of the HF patients were male (51.3%), almost half were smokers (46.2%), and the majority received ≤ six years of formal education. Most of the HF patients (87.2%) belonged to classes II and III of the New York Heart Association Functional Classification, with a mean ejection fraction of 47.15 ± 20.31 mL. The HF patients who attended the clinic (n = 38, 75.13 ± 5.89 yrs) were significantly younger than those who did not attend the clinic (n = 40, 79.53 ± 6.96 yrs) (P = 0.04), and had lower recorded blood pressure. No other statistically significant difference existed between the socio-demographic and clinical characteristics of the two groups. The HF patients who did not attend the nurse-led HF clinic demonstrated a significantly higher risk of hospital readmission [odd ratio (OR): 7.40; P < 0.01] than those who attended after adjusting for the effect of age and blood pressure. In addition, HF patients who attended the clinic had lower mortality (n = 4) than those who did not attend (n = 14). However, such a difference did not reach statistical significance when the effects of age and blood pressure were adjusted. A significant reduction in systolic blood pressure [F (2, 94) = 3.39, P = 0.04] and diastolic blood pressure [F (2, 94) = 8.48, P < 0.01] was observed among the HF patients who attended the clinic during the six-month period. Conclusions The finding of this study suggests the important role of nurse-led HF clinics in reducing healthcare burden and improving patient outcomes among HF patients in Hong Kong.  相似文献   
40.
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