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   1676篇
  免费   103篇
  国内免费   47篇
耳鼻咽喉   12篇
儿科学   62篇
妇产科学   69篇
基础医学   166篇
口腔科学   39篇
临床医学   186篇
内科学   400篇
皮肤病学   16篇
神经病学   70篇
特种医学   141篇
外科学   288篇
综合类   11篇
预防医学   106篇
眼科学   8篇
药学   90篇
  1篇
肿瘤学   161篇
  2023年   8篇
  2022年   14篇
  2021年   26篇
  2020年   18篇
  2019年   19篇
  2018年   34篇
  2017年   28篇
  2016年   32篇
  2015年   37篇
  2014年   50篇
  2013年   67篇
  2012年   61篇
  2011年   81篇
  2010年   59篇
  2009年   59篇
  2008年   71篇
  2007年   109篇
  2006年   70篇
  2005年   72篇
  2004年   39篇
  2003年   49篇
  2002年   53篇
  2001年   29篇
  2000年   52篇
  1999年   46篇
  1998年   56篇
  1997年   65篇
  1996年   63篇
  1995年   49篇
  1994年   35篇
  1993年   37篇
  1992年   21篇
  1991年   28篇
  1990年   29篇
  1989年   30篇
  1988年   39篇
  1987年   34篇
  1986年   22篇
  1985年   22篇
  1984年   11篇
  1983年   14篇
  1982年   11篇
  1981年   8篇
  1980年   12篇
  1979年   5篇
  1978年   8篇
  1977年   12篇
  1975年   7篇
  1970年   5篇
  1966年   4篇
排序方式: 共有1826条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.

Background  

Shoulder disorders are a common health problem in western societies. Several treatment protocols have been developed for the clinical management of persons with shoulder pain. However available evidence does not support any protocol as being superior over others. Systematic reviews provide some evidence that certain physical therapy interventions (i.e. supervised exercises and mobilisation) are effective in particular shoulder disorders (i.e. rotator cuff disorders, mixed shoulder disorders and adhesive capsulitis), but there is an ongoing need for high quality trials of physical therapy interventions. Usually, physical therapy consists of active exercises intended to strengthen the shoulder muscles as stabilizers of the glenohumeral joint or perform mobilisations to improve restricted mobility of the glenohumeral or adjacent joints (shoulder girdle). It is generally accepted that a-traumatic shoulder problems are the result of impingement of the subacromial structures, such as the bursa or rotator cuff tendons. Myofascial trigger points (MTrPs) in shoulder muscles may also lead to a complex of symptoms that are often seen in patients diagnosed with subacromial impingement or rotator cuff tendinopathy. Little is known about the treatment of MTrPs in patients with shoulder disorders.  相似文献   
5.
AIMS: The aim of this study is to compare PUMA curves with different pathologic conditions causing bladder dysfunction in 158 men and 83 women. METHODS: PUMA results in terms of bladder outlet obstruction and detrusor contractility were compared in 92 men with benign prostatic hypertrophy (BPH) and p(ves) congruent with p(det) (i.e., p(abd) congruent with 0) with the results of the urodynamics operator's opinion, the provisional International Continence Society method, Abrams and Griffith's diagram, urethral resistence factor (URA), Sch?fer's diagram, and Watt factor. PUMA curves correlated reliably with different pathologic conditions such as obstructive BPH, orthotopic bladder, cystocele, the neurological bladder, and bladder diverticulum. Statistical analysis indicated excellent agreement between PUMA and URA; agreement with other methods was good in cases of obstruction and nonobstruction. In doubtful cases, as diagnosed by standard methods, PUMA agreed only with the Abrams and Griffith's diagram. PUMA and Wmax were in good agreement on detrusor con traction force. Agreement between PUMA and Sch?fer's diagram was excellent for patients with detrusor hypercontractility and good for patients with detrusor hypocontractility and normocontractility. PUMA is the only method applicable to women. It is easy to perform. When integrated with other diagnostic tests, it provides realistic data for diagnosis, medical or surgical therapy, and outcome.  相似文献   
6.
OBJECTIVES: To examine the cancer risk of shoe manufacturing workers and evaluate whether the risk was associated with exposure to leather dust and solvents. METHODS: Data from two historical cohort studies of shoe workers were expanded and analysed in parallel. A total of 4215 shoemakers from England contributing 103 726 person-years at risk and 2008 shoemakers from Florence, Italy, contributing 54,395 person-years at risk were included in the analysis. Exposure to leather dusts and solvents from glues was evaluated on the basis of job title information. Standardised mortality ratios (SMR) were calculated as ratios of observed deaths (Obs) over expected derived from national mortalities. RESULTS: Overall mortality was lower than expected in both cohorts (English cohort: Obs 3314, SMR 81, 95% confidence interval (95% CI) 78-84; Florence cohort: Obs 333, SMR 87, 95% CI 78-97). An increased risk of nasal cancer was found (English cohort: Obs 12, SMR 741; Florence cohort: Obs 1, SMR 909). 10 of the 13 cases occurred among English workers employed in the manufacture of welted boots (SMR 926, 95% CI 444-1703), a sector of the industry thought to have had the highest exposure to leather dust. Mortality from leukaemia was not increased in the English cohort (Obs 16, SMR 89), but was increased in the Florence cohort (Obs 8, SMR 214, 95% CI 92-421); and the highest risk was found among shoe workers in Florence who were first exposed between 1950 and 1959 when exposure to benzene was substantial (Obs 3, SMR 536, 95% CI 111-1566). Some evidence for an excess risk of stomach, bladder, and kidney cancer, as well as multiple myeloma and non-Hodgkin's lymphoma was also found in the Florence cohort only among workers employed in jobs with the highest exposure to solvents. CONCLUSIONS: These findings confirm the associations between exposure to leather dust and nasal cancer and between exposure to benzene and leukaemia in the shoe manufacturing industry and suggest that the risk of other cancers may be increased among workers exposed to solvents or glues.  相似文献   
7.
A complication of sickle cell disease is proliferative retinopathy. We investigated the eyes from a transgenic mouse model of sickle cell disease (alpha H beta S[beta MDD] type) to determine if pathological changes occurred in their retinas and choroids. One retina from each animal was processed by flat-embedding adenosine diphosphatase-reacted retinas in glycol methacrylate. The fellow eye from each animal was embedded whole in glycol methacrylate for histopathological analysis of all ocular structures. Retinal vascular occlusions resulted in nonperfused areas of retina and arterio-venous anastomoses. Intra- and extraretinal neovascularization was observed adjacent to nonperfused areas. Retinal pigmented lesions were formed by the migration of retinal pigment epithelial cells into sensory retina, often ensheathing choroidal neovascularization. The incidence of this bilateral chorioretinopathy was 30% in animals older than 15 months of age. The ocular histopathological changes we observed in the mouse model mimicked many aspects of human proliferative sickle cell retinopathy. Furthermore, this is the first genetically derived animal model for chorio-retinal neovascularization.  相似文献   
8.
To define the prevalence of NANB hepatitis, anti-HCV antibodies were determined in 51 patients on renal replacement therapy, in 7 transplanted patients and 17 staff members of the hemodialysis unit. Anti-HCV antibodies were evaluated using immunoenzymatic methods (Ortho HCV ELISA Test System, 1st and 2nd generation). Among hemodialysis patients, seroconversion was respectively documented in 17.6% (9/51) and 52.9% (27/51); none of the transplanted patients were positive with the 1st generation test, while 3/7 were positive with the 2nd. No statistically significant difference was found in the prevalence antibodies between transfused and nontransfused patients. ALT levels were statistically greater in patients with anti-HCV antibodies (X2 2nd generation = 8.83; p less than 0.01). Our results suggest: (1) that hemodialysis represents a risk factor; (2) the validity of substitute markers and (3) more sensitivity of the 2nd than 1st generation test.  相似文献   
9.
During a multicenter evaluation, 16 methods for creatinine measurement have been tested according to the guidelines of the Société fran?aise de biologie clinique (SFBC) protocol. Kinetic Jaffé methods, widely used in France, performed on different analytical systems (Astra Beckman, IL 508, RA 1000 Technicon, Hitachi 704, 705, 717 Boehringer, Fara Roche, Progress Kone, Kem-O-Mat Coulter, Perspective France Monitor) have been compared to a continuous flow method with aqueous standards, to enzymatic methods using creatinine amidohydrolase with a colorimetric measurement (Boehringer and Ektachem Kodak) and to an HPLC method. Reproducibility, estimated with four different control sera, proved to be unsatisfactory in some cases as compared to current criteria for imprecision (less than +/- 10 mumol/l for intralaboratory and less than +/- 20 mumol/l for interlaboratory imprecision). The same selected patients sera covering the whole range of physiopathological concentrations have been analyzed with each method, and compared with the continuous flow results. Differences are more dependent on the sample than on the calibrators. The influences of haemolysis, bilirubin, acetoacetate, albumin, lipids, glucose, and some cephalosporins have been evaluated with spiked human sera. Haemolysed, turbid and jaundiced patient samples have been analyzed as well. The results vary according to the analytical procedure. This study took place in the implementation of a selected method for routine purpose with special regards to interferences and an acceptable imprecision. The method must satisfy the physicians' demands in the renal function exploration, especially in kidney-transplant patients.  相似文献   
10.
Pseudoachalasia is a rare clinical entity which has clinical, radiographic and manometric features often indistinguishable from achalasia. A small primary adenocarcinoma arising at the gastroesophageal junction or a tumor of the distal esophagus are the most frequent causes. Rarely, processes other than esophagogastric cancers may lead to the development of pseudoachalasia. We present three cases of pseudoachalasia in which the primary cause of the disease was not an esophagogastric cancer. The causes were a pancreatic carcinoma, a breast cancer and an histiocytosis X. Aspects of these three patients' diagnostic and therapeutic course are discussed in detail.  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