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   5071篇
  免费   250篇
  国内免费   11篇
耳鼻咽喉   49篇
儿科学   257篇
妇产科学   192篇
基础医学   635篇
口腔科学   63篇
临床医学   318篇
内科学   1112篇
皮肤病学   103篇
神经病学   372篇
特种医学   283篇
外科学   630篇
综合类   111篇
一般理论   1篇
预防医学   313篇
眼科学   303篇
药学   332篇
中国医学   13篇
肿瘤学   245篇
  2023年   33篇
  2022年   72篇
  2021年   131篇
  2020年   64篇
  2019年   96篇
  2018年   139篇
  2017年   98篇
  2016年   126篇
  2015年   140篇
  2014年   181篇
  2013年   209篇
  2012年   383篇
  2011年   397篇
  2010年   213篇
  2009年   183篇
  2008年   280篇
  2007年   294篇
  2006年   273篇
  2005年   243篇
  2004年   269篇
  2003年   204篇
  2002年   200篇
  2001年   117篇
  2000年   102篇
  1999年   73篇
  1998年   48篇
  1997年   29篇
  1996年   27篇
  1995年   15篇
  1994年   16篇
  1993年   21篇
  1992年   53篇
  1991年   45篇
  1990年   47篇
  1989年   40篇
  1988年   33篇
  1987年   37篇
  1986年   38篇
  1985年   30篇
  1984年   33篇
  1983年   24篇
  1982年   25篇
  1979年   22篇
  1978年   21篇
  1977年   17篇
  1976年   15篇
  1974年   19篇
  1973年   14篇
  1968年   14篇
  1967年   14篇
排序方式: 共有5332条查询结果,搜索用时 234 毫秒
61.
Breast carcinoma occurs rarely in men. Its imaging by mammography is difficult because male breast tissue is normally small in volume and adequate compression is not possible, which is a prerequisite for performing mammography. The authors describe a 65-year-old man with a right breast mass in whom the result of fine-needle aspiration cytology was inconclusive. A mammogram was also noncontributory because adequate compression was not possible as the mass was tender. Tc-99m tetrofosmin scintimammography showed intense focal uptake in the right breast. Excision biopsy confirmed the diagnosis of breast carcinoma.  相似文献   
62.
BackgroundNon-surgical factors have been found to have significant impact on outcome following Total Knee Arthroplasty (TKA). The study was conducted to know the independent effect of each of the four interacting psychological factors: anxiety, depression, pain catastrophizing and kinesiophobia on early outcome following TKA in an Indian population.Materials and Methods104 consecutive patients undergoing TKA were included in the study and followed up at 6 weeks, 6 months and one year. Preoperatively, Hospital Anxiety and Depression Scale was used to diagnose and quantify anxiety and depression, pain catastrophizing and kinesiophobia were assessed using Pain Catastrophizing Scale and Tampa Scale for Kinesiophobia, respectively. Outcome was assessed on the basis of Knee Society Score and Knee Injury and Osteoarthritis Outcome Score. Regression analysis was done to know independent effect of each factor on outcome scores.ResultsNine (8.7%) patients were found to have undiagnosed psychopathology. The patients with psychopathologies were found to have significantly worse knee outcome scores on follow-up, although the rate of improvement in knee symptoms and function was not significantly different from those without psychopathology. The degree of Anxiety correlated with worse knee pain and stiffness up to 6 months while it correlated with poor knee function for a longer duration. The degree of depression and pain catastrophizing correlated with worse knee pain, stiffness and function at all visits while kinesiophobia didn’t show correlation independent other factors.ConclusionPsychopathology was found to be associated poor knee outcome scores with degree of preoperative depression and pain catastrophizing as significant independent predictors as poor outcome, whereas the effect of degree of anxiety on knee pain and stiffness was found to wane over time. Kinesiophobia didn’t show any independent correlation.Supplementary InformationThe online version of this article (10.1007/s43465-020-00325-x) contains supplementary material, which is available to authorized users.  相似文献   
63.
OBJECTIVE: To study the pregnancy and offspring outcomes in postrenal transplant recipients. METHODS: This is a retrospective case-note review study investigating the outcome of 234 pregnancies in 140 renal transplant recipients from five different Middle Eastern countries. RESULTS: Of the overall pregnancies 74.4% were successful albeit with high prevalences of preterm and Caesarean deliveries (40.8% and 53%, respectively). The mean serum creatinine did not rise significantly during pregnancy in the group as a whole but did so in patients who had serum creatinine of or above 150 micromol/L at the beginning of their pregnancies. The mean birth weight was (2,458 g) with 41.3% of the newborns being of low birth weight (<2,500 g). The prevalences of stillbirths were 7.3% and of spontaneous abortion was 19.3%. Preeclampsia and gestational diabetes were observed in 26.1% and 2% of pregnancies, respectively. CONCLUSIONS: In the presence of good allograft function, the majority of pregnancies in renal transplant recipients have a good outcome but with increased incidence of preeclampsia, reduced gestational age, and low birth weights. Patients with baseline serum creatinine of above 150 micromol/L have an increased risk of allograft dysfunction resulting from the pregnancy.  相似文献   
64.
65.
The case is reported of a 37-year-old woman who complained of a gradually progressive mass in the left medial canthus area of one year's duration associated with epiphora. Although the clinical and investigative observations were suggestive of an acquired lacrimal sac cyst, the diagnosis was clinched by the operative and histopathological findings. Excision of the cyst along with dacryocystorhinostomy provided complete cure for this patient.  相似文献   
66.
PURPOSE: To examine the hypothesis that initial smear examination results have a significant bearing on the management and outcome of suspected microbial keratitis. MATERIALS AND METHODS: One hundred and seventy consecutive patients with suspected microbial keratitis were included in a prospective nonrandomized comparative study and their detailed clinical and microbiological data (smears and cultures of corneal scrapings) were captured on a predesigned corneal ulcer database. Patients were divided into two groups: Group 1 included 68 patients with corneal scrapings negative in smears while Group 2 included 102 patients with corneal scrapings positive in smears. The two groups were compared for their clinico-microbiological profile, management and clinical outcome. The outcome was noted at three months. Fisher's exact test was applied for statistical analysis. RESULTS: Cultures were sterile in 57.3% of patients in Group 1 compared to 17.6% in Group 2. Scrapings that grew S. pneumoniae, gram-negative organisms, fungi and Acanthamoeba were more often positive in smears (18.6%, 11.8%, 19.6% and 2.9% respectively). While data on duration of prior treatment was not available, prior medication made no significant difference to smear results. More (79.3%) patients of Group 1 had small infiltrate size (CONCLUSIONS: Initial smear examination helps in instituting specific therapy thereby improving the outcome in cases of microbial keratitis. Positive smears indicate greater severity of disease and prior medication may not be a significant cause of smear negativity.  相似文献   
67.
A 13-year-old male child had gradually progressive, bilaterall, symmetrical, erythematous hyperkeratotic plaques over knees, elbows, natal cleft, dorsa of hands and feet with palmoplantar keratoderma. High arched palate, fissured tongue and sternal depression (pectus-excavatum) were unusual associations.  相似文献   
68.
Different areas of the hypothalamus were stimulated by a stereotaxic technique before and after reserpine in unanaesthetized cats. Reserpine in a dose of 1 mg./kg. body weight increased the threshold of stimulation of hypothalamic areas in cats giving an initial pressor response. It decreased the threshold of stimulation of areas of the hypothalamus in animals giving an initial depressor response. Reserpine thus appeared to affect the hypothalamus directly in two ways. It depressed the sympathetic centres in the diencephalon and facilitated the parasympathetic ones.  相似文献   
69.
70.
An accurate, sensitive, precise, reliable, and quick method for the determination of cholesterol content by high-performance thin layer chromatography is developed. In this method, aluminum-backed precoated silica gel 60 F254 plates were used as the stationary phase and the samples were sprayed with the help of CAMAG sample applicator Linomat 5. The chromatogram was developed with the mobile phase consisting of chloroform:methanol (9.5:0.5, v/v). The samples were detected using CAMAG Scanner 4 and evaluated using the method developed on winCATS software. Densitometric analysis of cholesterol was performed in absorbance mode at 200 nm. In this solvent system, cholesterol gave a compact spot with an Rf value of 0.63 ± 0.03. The linear regression analysis of data for the calibration curve showed good linearity over a concentration range of 2–7 μg/spot with a regression value of 0.99933 and standard deviation of 1.44%. The limit of detection and limit of quantification were found to be 100 ng/spot and 500 ng/spot, respectively. Using the developed method, the concentration of cholesterol in the saponified and unsaponified egg yolk sample was determined. This method was found to be reproducible and can even be used for samples containing complex matrices.  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