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   508篇
  免费   31篇
  国内免费   1篇
儿科学   19篇
妇产科学   11篇
基础医学   73篇
口腔科学   3篇
临床医学   38篇
内科学   110篇
皮肤病学   10篇
神经病学   36篇
特种医学   13篇
外科学   43篇
综合类   2篇
预防医学   93篇
眼科学   7篇
药学   37篇
肿瘤学   45篇
  2024年   3篇
  2023年   7篇
  2022年   4篇
  2021年   37篇
  2020年   12篇
  2019年   33篇
  2018年   29篇
  2017年   21篇
  2016年   16篇
  2015年   20篇
  2014年   24篇
  2013年   29篇
  2012年   38篇
  2011年   41篇
  2010年   26篇
  2009年   23篇
  2008年   34篇
  2007年   37篇
  2006年   22篇
  2005年   14篇
  2004年   14篇
  2003年   9篇
  2002年   6篇
  2001年   8篇
  2000年   1篇
  1999年   6篇
  1997年   1篇
  1996年   6篇
  1995年   3篇
  1993年   2篇
  1992年   2篇
  1991年   2篇
  1989年   1篇
  1988年   3篇
  1986年   3篇
  1984年   1篇
  1981年   1篇
  1980年   1篇
排序方式: 共有540条查询结果,搜索用时 224 毫秒
1.
2.
3.
Human metapneumovirus (hMPV) genotypes A and B show epidemiological and probably clinical differences. This report describes a fast and simple PCR–restriction fragment length polymorphism (PCR-RFLP) assay, involving digestion of the fusion protein gene with Tsp 509I, that allows lineages A1, A2, B1 and B2 to be distinguished. The assay should help in elucidating the epidemiology of hMPV, and possibly in predicting the severity of clinical infection.  相似文献   
4.
The COVID-19 pandemic has significantly impacted daily activities worldwide. University students may have experienced substantial changes in daily living as a result of restrictions on university attendance. The return to normalcy may take a long time, and understanding the influence that shifts in daily routines have had on the lifestyles of university students may inform approaches to support overall well-being. We analyzed changes in the lifestyles of students enrolled at a health sciences university during the COVID-19 pandemic. This longitudinal study took place at the Faculty of Medicine and Nursing in the University of the Basque Country in Spain, and the final sample consisted of 113 nursing students, 109 medical students, and 45 physiotherapy students. Our results demonstrate changes in lifestyles of university students during the pandemic. MedDiet adherence scores and the percentage of students with high adherence increased during the pandemic. This increase was due to the increased consumption of vegetables and nuts. In terms of physical activity, the practice of moderate and intense physical activity was maintained. These results provide important information for both public health authorities and educational institutions to guide strategies to maintain the well-being of students and enhance opportunities for young adults to lead a healthy lifestyle.  相似文献   
5.
6.
Screening for mutations in candidate genes for hypospadias   总被引:2,自引:0,他引:2  
Hypospadias, a condition with a frontally placed urethral orifice on the penis, is the most common malformation in males. During fetal development several components are necessary for normal male genital development. Testosterone and dihydrotestosterone act via the androgen receptor but a defective receptor function results in different degrees of genital malformations. Testosterone-5α-reductase converts testosterone to dihydrotestosterone, which is crucial for normal differentiation, and a total lack of this enzyme results, in syndromes with hypospadias. The Wilms' tumour 1 (WT1) gene is expressed in the fetal gonad and genital malformations can occur due to WT1 gene mutations. These genes are therefore strong candidate genes for hypospadias. We have analysed 35 boys with hypopadias and one girl diagnosed as with complete androgen insensitivity syndrome, using exon by exon polymerace chain reaction (PCR) amplification of the AR, WT1 and 5α-reductase genes and screened for point mutations and performed subsequent DNA sequencing. No mutations in any of these genes were found in the 26 patients with isolated hypospadias. Two patients with severe hypospadias with cryptorchidism were found to carry mutations in the androgen receptor gene. Also the girl with clinically diagnosed complete androgen insensitivity was found to be homozygous for a splice mutation in the 5α-reductase gene. In summary, mutations in the WT1, AR and 5α-reductase genes are not common causes of isolated hypospadias. Received: 1 October 1997 / Accepted: 4 May 1998  相似文献   
7.
OBJECTIVE: To evaluate the appropriateness of the use of total hip joint replacements. DESIGN: Observational study of consecutive patients with a diagnosis of hip osteoarthritis and who had undergone total hip arthroplasty over a 1-year period from seven hospitals. MAIN MEASURES: The appropriateness of the use of hip replacement was judged by explicit criteria developed by a panel of experts using RAND methodology. The length of hospital stay during the admission and complications were recorded 6 months post-operatively. Patients were also surveyed 6 months after discharge to determine whether they believed they had recovered or their satisfaction with the intervention. Appropriateness results of this study were compared with a previous study performed with the same criteria 4 years previously. RESULTS: In total, 784 patients participated in the study. Indications for surgery were considered necessary in 52.2% of cases, appropriate in 21.3%, uncertain in 21.4%, and inappropriate in 5.1%. Differences were found in the rates of appropriateness exclusively from one hospital. At 6 months after discharge, differences between centres were found for the proportion of patients that reported they had recovered from surgery (range 57.7-24.8%) and in the length of hospital stay during admission (range 10-16 days). Improvement in the appropriateness rates were found for all participant hospitals during both periods. CONCLUSIONS: We identified a low percentage of inappropriate indications and differences in some outcomes between centres. Compared with previously, there has been improvement in the use of this technique, although both periods are not methodologically comparable.  相似文献   
8.
Diarrhetic shellfish poisoning (DSP) toxins of algal origin are frequent contaminants of coastal waters and seafood. The potential risk for human health due to the continuous presence of these toxins in food has not been clearly established. We have used cerebellar primary cultures to investigate the effects of the DSP toxin dinophysistoxin-2 (DTX-2) on central nervous system neurons and glial cells. Exposure to DTX-2 produced neurotoxicity at concentrations starting at 2.5 nM, characterized first by disintegration of neurites and later by cell death. DTX-2-induced neurodegeneration required long exposures (at least 20 h), involved DNA fragmentation and condensation and fragmentation of chromatin, typical hallmarks of apoptosis, and required the synthesis of new proteins. The concentration that reduced by 50% the maximum neuronal survival after 24 h exposure to DTX-2 (EC50(24)) was approximately 8 nM. Morphology and viability of glial cells remained unaffected up to at least 15 nM DTX-2. Higher concentrations of the toxin caused strong shrinkage of glial cell bodies and retraction of processes, and a significant reduction of glial cell viability. Glial toxicity by DTX-2 involved typical apoptotic condensation and fragmentation of chromatin. Compared to neurons, the effect on glial cells was a much shorter process, and extensive glial degeneration and death occurred after 7 h exposure to DTX-2 (EC50(7) approximately 50 nM; EC50(24) approximately 30 nM). Although further experiments are needed to confirm these toxic actions in vivo, our in vitro data suggest that chronic exposure to amounts of DSP toxins below the current safety regulatory limits may represent a risk for human health that should be taken into consideration.  相似文献   
9.
The objective of this study was to identify the social factors that explain the differences in knowledge with regards to HIV/AIDS among immigrants in the Basque Country (Spain). We conducted a cross-sectional study based on information obtained in the Basque Health Survey for 754 immigrants from: 86 China, 368 Latin America, 237 the Maghreb and 74 Senegal. Odds ratios (95% CI) were calculated from logistic regression models to measure the degree of association between inadequate knowledge regarding transmission, prevention and places where HIV testing is offered, and the independent variables. We found that this inadequate knowledge is associated with place of birth, sex, a lower level of education, immigration status, difficulties in understanding Spanish, and not receiving advice about AIDS in primary care. These findings indicate that initiatives must be developed to promote equity in the provision of healthcare through clinical guidelines, including details of the specific needs of different groups of immigrants and considering gender issues.  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