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   610篇
  免费   41篇
  国内免费   9篇
耳鼻咽喉   6篇
儿科学   15篇
妇产科学   7篇
基础医学   42篇
口腔科学   13篇
临床医学   80篇
内科学   136篇
皮肤病学   5篇
神经病学   29篇
特种医学   72篇
外科学   49篇
综合类   56篇
预防医学   71篇
眼科学   6篇
药学   32篇
中国医学   1篇
肿瘤学   40篇
  2022年   5篇
  2021年   5篇
  2020年   12篇
  2019年   12篇
  2018年   8篇
  2017年   6篇
  2016年   6篇
  2015年   13篇
  2014年   13篇
  2013年   17篇
  2012年   22篇
  2011年   19篇
  2010年   18篇
  2009年   26篇
  2008年   19篇
  2007年   27篇
  2006年   21篇
  2005年   19篇
  2004年   34篇
  2003年   19篇
  2002年   26篇
  2001年   22篇
  2000年   17篇
  1999年   14篇
  1998年   19篇
  1997年   25篇
  1996年   12篇
  1995年   10篇
  1994年   9篇
  1993年   7篇
  1992年   10篇
  1991年   10篇
  1990年   5篇
  1989年   11篇
  1988年   14篇
  1987年   10篇
  1986年   11篇
  1985年   9篇
  1984年   6篇
  1983年   14篇
  1982年   10篇
  1981年   5篇
  1980年   7篇
  1979年   4篇
  1978年   5篇
  1974年   6篇
  1972年   5篇
  1971年   4篇
  1958年   11篇
  1957年   4篇
排序方式: 共有660条查询结果,搜索用时 0 毫秒
91.
Given the increased access of antiretroviral therapy (ART) throughout the developing world, what was once a terminal illness is now a chronic disease for those receiving treatment. This requires a paradigmatic shift in service provision for those affected by HIV/AIDS in low-resource settings. Although there is a need for psychosocial support interventions for HIV-affected youth and their caregivers, to date there has been limited empirical evidence on the effectiveness of curriculum-based psychosocial support groups in HIV-affected families in low-income countries. Therefore, the purpose of this study is to examine the feasibility and assess the preliminary effectiveness of a psychosocial support group intervention for HIV-affected youth and their caregivers in central Haiti. The study was conducted at six Partners In Health-affiliated sites between February 2006 and September 2008 and included quantitative as well as qualitative methods. HIV-affected youth (n = 168) and their caregivers (n = 130) completed a baseline structured questionnaire prior to participation in a psychosocial support group intervention. Ninety-five percent of families completed the intervention and a follow-up questionnaire. Psychological symptoms, psychosocial functioning, social support, and HIV-related stigma at baseline were compared with outcomes one year later. Qualitative methods were also used to assess the participants' perspectives of the intervention. Comparing pre- and post-intervention assessment, youth affected by HIV experienced decreased psychological symptoms as well as improved psychosocial functioning and social support. Caregivers (95% HIV-positive) demonstrated a significant reduction in depressive symptoms, improved social support, and decreased HIV-related stigma. Although further study is needed to assess effectiveness in a randomized controlled trial, corroborative findings from qualitative data reflected reduced psychological distress, less social isolation and greater hope for the future for families affected by HIV/AIDS following the intervention.  相似文献   
92.

Background:

Lymphatic Filariasis is a mosquito transmitted disease, caused by parasitic worm Wuchereria bancrofti. Global Programme for Elimination of Lymphatic Filariasis was established in early 2000. The strategy recommended by the World Health Organization is annual Mass Drug Administration (MDA) of single-dose of Diethylcarbamazine 6 mg/kg (DEC), distributed to inhabitants of Filariasis endemic areas, excluding children below 2 years of age, pregnant women, and seriously ill persons, and Morbidity Management. The health system distributes the drugs by a door-to-door strategy.

Objective:

To assess the coverage and compliance of MDA in Bidar district during the campaign in November 2008.

Materials and Methods:

Cross-sectional population-based house-to-house visit. Outcome is assessed as actual coverage and compliance, in Percentage and proportions.

Results:

Eight clusters, total eligible population of 1 131 individuals were interviewed. The coverage rate was 78% with variation across different areas. The compliance with drug ingestion was 68%.

Conclusion:

The effective coverage was below the target (85%). Side effects of DEC were minimum, the overall coverage was better in rural areas compared with urban areas.  相似文献   
93.
94.
Griffin  JH; Mosher  DF; Zimmerman  TS; Kleiss  AJ 《Blood》1982,60(1):261-264
Activated protein C is a potent anticoagulant and profibrinolytic enzyme that can be derived from the vitamin-K-dependent serine protease zymogen, protein C, by the action of thrombin. Protein C antigen concentration was determined in plasmas from normals (n = 40) and from 38 patients with intravascular coagulation as evidenced by positive FDP (greater than micrograms/ml). Plasma protein C was 4 micrograms/ml in normals and was significantly depressed (less than 2 SD below the mean of normals) in 19 of the 38 patients. Of 15 patients with suspected intravascular coagulation but normal FDP, protein C was decreased in 5 individuals; 3 of these 5 patients had liver disease. Based on these results, we suggest that extensive activation of the coagulation system in vivo causes a significant consumption of protein C, presumably due to its activation by thrombin and subsequent clearance.  相似文献   
95.
Despite research on psychosocial and physical correlates of caregiving, associations of caregiving with cognitive functioning have rarely been studied. We compared the cognitive functioning of 44 spouse caregivers of persons with Alzheimer's disease to 66 demographically-similar non-caregiver spouses; and, whether such differences are explained by demographic variables and distress. We observed that variance in Digit Symbol scores was explained by age [F(1,108)=26.80, p<.001, R(2)=.20] and education [DeltaF(1,107)=5.33, p=.023, DeltaR(2)=.04], and caregiver status [DeltaF(1,106)=4.57, p<.035, DeltaR(2)=.03]. However, when Distress (a composite of Uplifts, Burden, and Sleep Problems) was added to the equation, the lower level of cognitive functioning in caregivers was no longer significant (beta declined from.18 to.06), but distress was significant (beta=-.30). These results may have implications for caregiver adherence and may have relevance to the complex tasks caregivers must perform for care-recipients and the information they report to health care workers/researchers about their care-recipients.  相似文献   
96.
Kickler  TS; Herman  JH; Furihata  K; Kunicki  TJ; Aster  RH 《Blood》1988,71(4):894-898
Baka is a platelet alloantigen whose putative allele, Bakb, has not been identified previously. By using a serum, "Har," obtained from a patient with posttransfusion purpura, we describe the platelet alloantigen Bakb. The Har serum reacted with an NP-40-extractable platelet membrane protein of 142 kd with mobility similar to platelet glycoprotein IIb alpha. We found that the antigen recognized by the Har serum is inherited in an autosomal dominant mode with an apparent gene frequency of .39. Chi-square analysis of observed and expected phenotype frequencies indicated that serum Har recognizes Bakb, the anticipated allele of Baka. Our findings provide new evidence for polymorphism of glycoprotein IIb and for the association of posttransfusion purpura with alloimmunization to determinants on this glycoprotein.  相似文献   
97.
98.
Thyroid hormones [predominantly 3,5,3'-triiodo-L-thyronine (T3)] regulate cholesterol and lipoprotein metabolism, but cardiac effects restrict their use as hypolipidemic drugs. T3 binds to thyroid hormone receptors (TRs) alpha and beta. TRbeta is the predominant isoform in liver, whereas T3 effects on heart rate are mediated mostly by TRalpha. Drugs that target TRbeta or exhibit tissue-selective uptake may improve plasma lipid levels while sparing the heart. Here, we asked how the TRbeta- and liver uptake-selective agonist GC-1 influences cholesterol and triglyceride metabolism in euthyroid mice. GC-1 treatment reduced serum cholesterol levels by 25% and serum triglycerides by 75% in chow-fed mice and also attenuated diet-induced hypercholesterolemia. GC-1 reduced plasma high-density lipoprotein cholesterol levels; increased expression of the hepatic high-density lipoprotein receptor, SR-BI; stimulated activity of cholesterol 7alpha-hydroxylase; and increased fecal excretion of bile acids. Collectively, these results suggest that GC-1 stimulates important steps in reverse cholesterol transport. Use of TRbeta and uptake selective agonists such as GC-1 should be further explored as a strategy to improve lipid metabolism in dyslipoproteinemia.  相似文献   
99.
Saba  HI; Saba  SR; Dent  J; Ruggeri  ZM; Zimmerman  TS 《Blood》1985,66(2):282-286
Type IIB von Willebrand disease is characterized by enhanced ristocetin- induced platelet aggregation and absence of large von Willebrand factor multimers from plasma. An alteration of the von Willebrand factor molecule resulting in increased reactivity with platelets appears to be the basis for these abnormalities. We have now identified a new variant of type IIB von Willebrand disease in a family in which the four affected members also have chronic thrombocytopenia, in vivo platelet aggregate formation, and spontaneous platelet aggregation in vitro. In spite of repeatedly prolonged bleeding times and persistent thrombocytopenia, their bleeding diathesis is only moderate.  相似文献   
100.
Gut microbiota shows host-specific diversity and temporal stability and significantly contributes to maintenance of a healthy gut. However, in inflammatory bowel disease, this microbiota has been implicated as a contributory factor to the illness. This study compared bacterial dynamics in Crohn's disease patients to those in a control group using a culture-independent method to assess the temporal stability, relative diversity, and similarity of the dominant fecal microbiota, Clostridium spp., Bacteroides spp., Bifidobacterium spp., and lactic acid bacteria spp. (LAB) for all individuals. Fecal samples were collected over several time points from individuals with Crohn's disease who were in remission (n = 11), from Crohn's disease patients who relapsed into an active Crohn's disease state (n = 5), and from a control group (n = 18). Denaturing gradient gel electrophoresis profiles were generated for the different microbial groups by specifically targeting different regions of the 16S rRNA gene and were compared on the basis of similarity and diversity. The temporal stability of dominant species for all Crohn's disease patients was significantly lower (P < 0.005) than that for the control group. Analysis of group-specific profiles for Bifidobacterium spp. found that they were similar in all samples, while the diversity of the LAB varied significantly between the groups, but temporal stability was not significantly altered. We observed significant changes in two functionally important mutualistic groups of bacteria, viz., Clostridium and Bacteroides spp., which may have implications for the host's gut health, since some genera are involved in production of short-chain fatty acid, e.g., butyrate.  相似文献   
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