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   15512篇
  免费   1545篇
  国内免费   31篇
耳鼻咽喉   160篇
儿科学   363篇
妇产科学   298篇
基础医学   2096篇
口腔科学   335篇
临床医学   1888篇
内科学   3347篇
皮肤病学   168篇
神经病学   1511篇
特种医学   535篇
外国民族医学   1篇
外科学   1938篇
综合类   373篇
一般理论   17篇
预防医学   1596篇
眼科学   244篇
药学   1347篇
中国医学   13篇
肿瘤学   858篇
  2021年   228篇
  2020年   147篇
  2019年   245篇
  2018年   250篇
  2017年   218篇
  2016年   217篇
  2015年   283篇
  2014年   348篇
  2013年   541篇
  2012年   741篇
  2011年   794篇
  2010年   445篇
  2009年   443篇
  2008年   636篇
  2007年   792篇
  2006年   744篇
  2005年   740篇
  2004年   652篇
  2003年   675篇
  2002年   613篇
  2001年   476篇
  2000年   476篇
  1999年   442篇
  1998年   194篇
  1997年   160篇
  1996年   156篇
  1995年   152篇
  1994年   165篇
  1993年   147篇
  1992年   341篇
  1991年   339篇
  1990年   262篇
  1989年   266篇
  1988年   265篇
  1987年   264篇
  1986年   243篇
  1985年   225篇
  1984年   206篇
  1983年   186篇
  1982年   137篇
  1981年   116篇
  1980年   109篇
  1979年   166篇
  1978年   153篇
  1977年   114篇
  1976年   134篇
  1974年   133篇
  1973年   172篇
  1972年   121篇
  1968年   108篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
Isolated single myocytes were prepared from myocardium of developing ventricular aneurysms and from myocardium within the scar of chronic ventricular aneurysms. The morphology and function of the individual cells were compared. The cells from developing aneurysms were rod-shaped, with a distinct sarcomeric structure, but did not contract even in the presence of high calcium concentrations. The sarcomere length was significantly higher than that of cells from chronic aneurysms and approached the theoretical point at which no contraction can occur. Cells from chronic aneurysms were either rod-shaped and contractile, or rounded due to hypercontracture of the myofilaments. Electron microscopy of cells from developing aneurysms confirmed the presence of elongated sarcomeres, a loss of the actin-myosin interdigitation, and damage to the contractile proteins which was particularly evident in the thin filaments. Cells with similar characteristics have also been isolated from a ruptured, ischaemic papillary muscle. These changes, which are due either to ischaemia or to overstretching of cells, may account for the weakness of the wall of developing aneurysms and be a cause of rupture or enlargement.  相似文献   
102.
103.
Cells secreting antibody to H-2 alloantigens can be detected in vitro by the alloantibody plaque assay. This test has been modified to allow the earlier and more objective determination of plaques by staining the lysed target cells with trypan blue. Details are given of optimum conditions necessary for the assay.  相似文献   
104.
105.
106.
This report presents an analysis of the Alcohol Intervention Program (AIP) at Parkland Memorial Hospital in Dallas, Texas. This pilot project was initiated in January of 1983. A total of 1,822 patients were screened by two trained counselors. Operated in the emergency room, the project significantly reduced the rate of both hospital admissions and readmissions for patients with alcohol-related illnesses. This project demonstrated its effectiveness by making appropriate referrals to local alcoholism service providers. A total of 387 patients were referred directly to Alcoholics Anonymous and 440 were referred to residential alcoholism programs. Of the latter group, follow-up documentation demonstrated that nearly half of those referred remained in treatment for the duration of the program.  相似文献   
107.
Maternal and Child Health Journal - Educational attainment has been demonstrated as a protective factor for the physical and mental health of children into adulthood, yet there has been limited...  相似文献   
108.
ObjectiveTo assess the feasibility of enrollment and collecting patient-reported outcome (PRO) data as part of routine clinical urologic care for bladder and prostate cancer patients and examine overall patterns and racial variations in PRO use and symptom reports over time.Subjects/Patients and MethodsWe recruited 76 patients (n = 29 Black and n = 47 White) with prostate or bladder cancer at a single, comprehensive cancer center. The majority of prostate cancer patients had intermediate risk (57%) disease and underwent either radiation or prostatectomy. Over half (58%) of bladder cancer patients had muscle invasive disease and underwent cystectomy.Patients were asked to complete PRO symptom surveys using their preferred mode [web- or phone-based interactive voice response (IVR)]. Symptom summary reports were shared with providers during visits. Surveys were completed at 3 time points and assessed urinary, sexual, gastrointestinal, anxiety/depression, and sleep symptoms. Feasibility of enrollment and survey completion were calculated, and linear mixed effects models estimated differences in outcomes by race and time.ResultsSixty three percent of study participants completed all PRO measures at all 3 time points. Black patients were more likely to select IVR as their survey mode (40% vs. 13%, P < 0.05), and less likely to complete all surveys (55% vs. 74%, P = 0.13). Patients using IVR were also less likely to complete all surveys (41% vs. 69%, P = 0.046).ConclusionsReported preferences for survey mode and completion rates differ by race, which may influence survey completion rates and highlight potential obstacles for equitable implementation of PROs into clinical care.  相似文献   
109.
BackgroundWe tested if disrupting iron utilisation by P. aeruginosa by adding the Tris-buffered chelating agent CaEDTA to nebulised tobramycin would enhance bacterial clearance and improve lung function in CF patients.MethodsIn this double-blind, randomised controlled trial, 26 episodes (25 patients) with P. aeruginosa infection admitted to two CF centres for treatment of an acute pulmonary exacerbation were randomly assigned to receive either 75 mg CaEDTA in Tris-buffered saline or placebo (Tris-buffered saline) nebulised in combination with 250 mg tobramycin twice daily for six weeks followed with four week safety follow-up. Primary endpoints were safety, tolerability, and bacterial density of P. aeruginosa. A secondary endpoint was lung function.ResultsThe study drug was well tolerated with adverse events comparable in both groups. The mean (SD) reduction in sputum P. aeruginosa count (log10 CFU/g) in the CaEDTA vs placebo group was 2·05 (2·57) vs 0·82 (2·71) at two weeks relative to admission (p = 0·39). The mean improvement in ppFEV1 was 16 vs 5 (p = 0·16); 11 vs 2 (p = 0·28); and 6 vs 2 percentage points (p = 0·47) at two, six, and ten weeks in CaEDTA and placebo groups, respectively.ConclusionsIn this pilot study in CF patients, an increase in the reduction of sputum density of P. aeruginosa and an increase in ppFEV1 was observed in the group of patients who received Tris-CaEDTA added to inhaled tobramycin compared to the group who received inhaled tobramycin alone, although these differences were not statistically significant. The treatment was also shown to be safe.  相似文献   
110.

Sociosexuality and sexual compulsivity predict sex differences in voyeuristic interest in the population. In this study, we used a sample of 1113 participants from the UK (46% men) to consider whether sociosexuality and sexual compulsivity interacted to explain these sex differences and whether this relationship extended to the related domain of exhibitionism. In doing so, we tested novel predictions derived from an evolutionary perspective which views voyeuristic and exhibitionistic interest as manifestations of a short-term mating strategy. Participants reported their levels of repulsion toward voyeurism and exhibitionism and their interest in performing such acts under different levels of risk. There were clear sex differences in voyeuristic and exhibitionistic repulsion that were partially mediated by the serial combination of sociosexuality and sexual compulsivity. Examining the sexes separately revealed qualitatively different relationships between sociosexuality and sexual compulsivity when predicting exhibitionistic, but not voyeuristic, repulsion. Combined, sociosexuality and sexual compulsivity also mediated the sex difference in willingness to commit acts of voyeurism, but not exhibitionism, which was equally low for both sexes. The results highlight the role sociosexuality plays in voyeuristic and exhibitionistic interest, which coupled with an evolutionary perspective, may have implications for how we view courtship disorders.

  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