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   542篇
  免费   34篇
  国内免费   1篇
耳鼻咽喉   19篇
儿科学   16篇
妇产科学   11篇
基础医学   72篇
口腔科学   12篇
临床医学   70篇
内科学   108篇
皮肤病学   17篇
神经病学   57篇
特种医学   12篇
外科学   53篇
预防医学   59篇
眼科学   23篇
药学   32篇
中国医学   5篇
肿瘤学   11篇
  2023年   5篇
  2022年   15篇
  2021年   12篇
  2020年   7篇
  2019年   11篇
  2018年   14篇
  2017年   15篇
  2016年   13篇
  2015年   13篇
  2014年   16篇
  2013年   28篇
  2012年   36篇
  2011年   35篇
  2010年   32篇
  2009年   14篇
  2008年   30篇
  2007年   32篇
  2006年   32篇
  2005年   30篇
  2004年   33篇
  2003年   15篇
  2002年   12篇
  2001年   12篇
  2000年   5篇
  1999年   10篇
  1998年   13篇
  1997年   9篇
  1996年   5篇
  1995年   5篇
  1994年   7篇
  1993年   6篇
  1992年   4篇
  1991年   4篇
  1990年   3篇
  1989年   6篇
  1988年   2篇
  1986年   2篇
  1982年   3篇
  1981年   5篇
  1980年   1篇
  1979年   2篇
  1978年   4篇
  1976年   1篇
  1975年   1篇
  1974年   1篇
  1973年   5篇
  1971年   2篇
  1969年   2篇
  1967年   1篇
  1966年   2篇
排序方式: 共有577条查询结果,搜索用时 15 毫秒
61.
Background and objective: Impairment of respiratory function has been described in end‐stage multiple sclerosis (MS), as well as in patients with mild to severe disability. No data are available regarding the respiratory function of MS patients without disability. The objective of this study was to assess the pulmonary function, respiratory muscle strength and carbon monoxide diffusion capacity of the lungs (DLCO) in patients with relapsing‐remitting multiple sclerosis (RRMS) without disability. Methods: Twenty‐seven RRMS patients and 25 healthy control subjects were recruited. All subjects underwent clinical and neurological examination, and spirometry; lung volumes, DLCO and maximal respiratory pressures were measured. All subjects were rated on the Modified Fatigue Impact Scale and Fatigue Severity Scale scales. Results: There were no significant differences in age, gender, height, weight or body mass index between the groups. The mean duration of illness in the MS group was 5.44 ± 3.74 years, and the mean Expanded Disability Status Scale was 0.62 ± 0.65. The mean values for total lung capacity, forced expiratory volume in 1 s (FEV1) and FEV1/FVC were normal in both groups. Fifteen RRMS patients exhibited a reduction in maximal expiratory pressure (MEP), but only one patient exhibited a reduction in maximal inspiratory pressure. The mean values for DLCO were lower in RRMS patients (P = 0.0004) than in the control group. DLCO was decreased in 15 (55.55%), out of 27 RRMS patients. The fatigue scale results were not correlated with pulmonary function test results Conclusions: DLCO and MEP may be impaired in RRMS patients without disability.  相似文献   
62.
BackgroundRheumatoid arthritis is the most common chronic inflammatory disease in the UK. Serological status such as rheumatoid factor (RF) and anti-citrullinated peptide antibody (ACPA) positivity predict poor outcomes. Early intensive treatment regimens targeting remission reduce disease activity, structural damage, and long-term disability. However, we do not know whether all patients with active disease should have such intensive treatment regimens. Can serological status be used to predict the need for intensive therapy?MethodsWe analysed samples from a published randomised controlled trial which compared four treatment regimens in patients with early active rheumatoid arthritis (disease duration <2 years): methotrexate monotherapy, double therapy (methotrexate plus either ciclosporin or prednisolone), and triple therapy (methotrexate plus ciclosporin plus prednisolone). The trial randomised 467 patients (68% female, median age 54 years [IQR 46–63]). Disease activity was assessed with the disease activity score of 28 joints (DAS28). Remission was defined as DAS28 less than 2·6 at 24 months. RF isotypes (IgM and IgA) and ACPA levels were measured with commercial ELISA kits. Statistical analysis used Pearson's chi-squared test.Findings402 (86%) patients were positive for IgM RF, 346 (74%) for IgA RF, and 346 (74%) for ACPA. 98 (21%) patients achieved remission at 24 months. In RF IgM negative cases (n=65) the proportion of patients achieving remission at 24 months was similar in all treatment groups (25%, 22%, and 30% for monotherapy, double therapy, and triple therapy, respectively). In RF IgM positive cases, significantly fewer patients achieved remission with monotherapy (13/65, 17%) and double therapy (24/157, 15%) than with triple therapy (27/80, 34%) (p=0·001). There were similar, consistent findings with IgA RF and ACPA, with significantly more seropositive patients achieving remission with triple therapy than with monotherapy.InterpretationContemporary treatment of rheumatoid arthritis emphasises the use of intensive therapy to achieve remission. However, we have shown that not all patients require such an aggressive approach to therapy. Given the heterogeneity of the diease, treatment should be personalised to the individual, which would minimise costs of treatment as well as potentially toxic side-effects. Our study shows that only seropositive patients with rheumatoid arthritis should be given more intensive therapies.FundingNational Institute for Health Research.  相似文献   
63.
64.
By changing the buffer system in the phenolic glycolipid-I (PGL-I) enzyme-linked immunosorbent assay (ELISA) the sensitivity of the test was increased without altering its specificity. Using a Tris-HCl buffer, significant titers of > or = 1:300 were found in 53.1% of the sera in paucibacillary (PB) and 98.0% of the sera in multibacillary (MB) groups of patients. Titer levels were also significantly increased. In the PB group of patients with Tris-HCl, the highest titer detected was 1:1200; in the MB group of patients, 1:76,800. Through this modification of the buffer system a more sensitive test was obtained thereby increasing the detectable level of PGL-I antibodies in both the PB and MB groups of patients.  相似文献   
65.
66.
67.
Poor walking performance is predictive of heart disease and osteoporosis and increases the risk of death in the elderly. Gait and vision have been identified as the most valuable physical functions according to multiple sclerosis patients' perceptions. The objective of this study was to perform a translation and cross-cultural adaptation of the Multiple Sclerosis Walking Scale (MSWS-12) into Brazilian Portuguese. A study of cross-cultural adaptation was conducted in ten steps. Participation in the study included four translators, two back-translators, twelve medical experts, twelve patients, twelve healthy subjects, and a Portuguese language expert. Only the question "Did standing make it more difficult to do things?" posed difficulty in the translation process. Maximum time for completion was less than three minutes (171 seconds). Internal consistency analyses showed high reliability (Cronbach's alpha = 0.94). The content validation and internal consistency stages were completed satisfactorily.  相似文献   
68.
Triterpene trimers from Maytenus scutioides: cycloaddition compounds?   总被引:2,自引:0,他引:2  
Two novel trimers, triscutins A and B (1 and 2), based on pristimerin triterpene units, were isolated and characterized from Maytenus scutioides. Their structures were determined on the basis of spectroscopic evidence, including 1H-13C heteronuclear correlation (HMQC), long-range correlation with inverse detection (HMBC), and ROESY NMR experiments; and their absolute configurations, by means of CD studies. Compounds 1 and 2 were assayed for antimicrobial and cytotoxic activities, and their possible biosynthetic route is proposed.  相似文献   
69.
70.
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