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   1735篇
  免费   163篇
  国内免费   2篇
耳鼻咽喉   9篇
儿科学   86篇
妇产科学   47篇
基础医学   235篇
口腔科学   9篇
临床医学   286篇
内科学   254篇
皮肤病学   52篇
神经病学   178篇
特种医学   23篇
外科学   162篇
综合类   44篇
一般理论   2篇
预防医学   209篇
眼科学   13篇
药学   150篇
中国医学   5篇
肿瘤学   136篇
  2024年   2篇
  2023年   20篇
  2022年   14篇
  2021年   48篇
  2020年   25篇
  2019年   54篇
  2018年   48篇
  2017年   40篇
  2016年   52篇
  2015年   46篇
  2014年   59篇
  2013年   102篇
  2012年   135篇
  2011年   129篇
  2010年   77篇
  2009年   66篇
  2008年   96篇
  2007年   101篇
  2006年   115篇
  2005年   78篇
  2004年   103篇
  2003年   93篇
  2002年   87篇
  2001年   17篇
  2000年   22篇
  1999年   22篇
  1998年   19篇
  1997年   13篇
  1996年   23篇
  1995年   10篇
  1994年   17篇
  1993年   10篇
  1992年   18篇
  1991年   15篇
  1990年   9篇
  1989年   10篇
  1988年   14篇
  1987年   10篇
  1986年   5篇
  1985年   9篇
  1984年   6篇
  1983年   3篇
  1982年   14篇
  1981年   14篇
  1980年   6篇
  1979年   6篇
  1977年   2篇
  1975年   3篇
  1974年   3篇
  1973年   2篇
排序方式: 共有1900条查询结果,搜索用时 31 毫秒
81.
This study tested cervical and oral human papillomavirus (HPV) infection in HIV-1 seropositive (HIV+) and seronegative (HIV-) women to determine any association between infections at both sites and the difference in prevalence of the HPV types infecting these women. Participants were 115 women referred to a colposcopy clinic after diagnosis of abnormal cervical cytology. The women showed low grade cervical intraepithelial neoplasia (CIN1) or high grade disease (CIN2/3) or no CIN based on colposcopy and histology. Typing of HPV in cervical and oral cells was by Roche linear array and included direct sequencing on selected oral samples. Cervical HPV prevalence was 86.5% and 97.1% in HIV- and HIV+ women respectively. With the exception of HPV-45, prominent in HIV+ women, the hierarchy of predominant types were similar in HIV- and HIV+ women. HPV-16 was most prevalent in both HIV+ (41.7%) and HIV- women (38.5%) with CIN2/3. Significantly more HIV+ women had multiple cervical (>1) infections than HIV- women (36.1% vs. 88.2%, P < 0.001) and more oral HPV infections (45.5% and 25% respectively; P = 0.04). The most prevalent oral HPV types were HPV-33, -11, and -72. The majority of women did not have concordant oral and cervical HPV types, reflecting possible independence of infection at the two sites. HIV immune suppression did not impact significantly on the predominant types of cervical HPV infection (except for HPV-45). HIV+ women had more multiple HPV infections and those with severe cervical disease a similar prevalence of HIV-16 but a lower HPV-18 prevalence than HIV- women.  相似文献   
82.
OBJECTIVES: Sternal osteomyelitis following cardiac surgery often requires debridement and flap coverage. The VAC (vacuum-assisted closure) device has been useful in complex wound coverage. A retrospective review of a single surgeon's experience with sternal reconstruction using the VAC device as an adjunct to debridement and muscle flap reconstruction was performed. METHODS: Thirteen consecutive patients over a 34-month period underwent debridement and reconstruction of sternal wounds. Eleven patients (85%) were males, and two (15%) were females. Mean age was 61 years (range: 43-73 years). Acute purulent sternal infections occurred in seven patients, while chronic sternal osteomyelitis was seen in six patients. Use of the VAC device during the perioperative period was evaluated. RESULTS: Of the 13 patients, the VAC device was used prior to flap closure in six patients, and after flap closure in two patients. Sternal debridement with bilateral pectoralis muscle flaps was used to reconstruct 12 patients, and one patient underwent debridement only with VAC placement. All 13 patients (100%) had complete closure of their complex wounds at an average of follow-up of 14 months. CONCLUSIONS: The VAC device is useful in the treatment of sternal osteomyelitis in three contexts: (1) as a temporary wound care technique preoperatively that minimizes dressing changes and prevents shear stresses of an open sternum, (2) as the sole method of wound closure in specific cases, and (3) as a technique to facilitate healing in postoperative flap reconstruction cases complicated by reinfection.  相似文献   
83.
84.
85.
86.
Previous research has established that social anxiety occurs at different rates in African American and European American populations (Grant et al., 2005), while psychometric investigations of widely used measures of psychopathology show differences in factor structure based on ethnic background (Carter et al., 1999, Chapman et al., 2009b). The current study examined response characteristics of 1276 African American and European American undergraduates completing the Fear of Negative Evaluation and Social Avoidance and Distress Scales (Watson & Friend, 1969). Confirmatory factor analyses failed to demonstrate factorial invariance in the two ethnic samples, and Wald tests suggested several items on both measures be dropped for African Americans. Results suggest the FNE and SAD operate differently across ethnic groups. Implications for the cross-cultural measurement of social anxiety and the importance of continued rigorous psychometric inquiry of commonly used measures are discussed.  相似文献   
87.

Objective  

The purpose of this study is to establish whether omitting routine postnatal examination on maternity units increases the risk of hospitalisation in the first week of life of the newborn.  相似文献   
88.
Controversy exists about the safety of the parenteral iron dextran products, Dexferrum and INFeD, which have been associated with rare, serious anaphylactic‐type reactions. In the United States, their product labels carry boxed warnings of this adverse event; some have called for the withdrawal from marketing of the higher molecular weight Dexferrum. Between 2002 and 2007, sales of Dexferrum, INFeD, and iron gluconate Ferrlecit declined 32.5%, 21%, and 4.8%, respectively, while sales of iron sucrose Venofer increased 160%. Voluntary reports submitted to the Food and Drug Administration show anaphylactic reactions and symptoms for the four parenteral iron products. Because of underreporting, possible differential reporting, absence of iron dextran brand names, and incomplete use (denominator) data, incidence rates and relative risk estimates cannot be calculated. U.S. death certificate data show that for most years from 1979 through 2006, no more than 3 deaths per year were coded to “adverse events in therapeutic use of iron preparations;” brand names were not consistently recorded. Emergency department data show small numbers of visits for treatment of allergic reactions with intravenous iron preparations. The data presented herein show that allergic reactions are possible with all four parenteral iron products, and it is difficult to determine which product has the largest risk based on sales data, voluntarily submitted adverse event reports, death certificates, ED visits, and observational studies performed to date. To help differentiate risk among the parenteral iron products, the brand name of the product always should be provided on medical records, death certificates, and adverse drug reaction reports. Am. J. Hematol., 2010. Published 2010 Wiley‐Liss, Inc.  相似文献   
89.
90.
The surprising disparity between the number of protein-encoding genes ( approximately 30,000) in the human genome and the number of proteins ( approximately 300,000) in the human proteome has inspired the development of translational proteomics aimed at protein expression profiling of disease states. Translational proteomics, which offers the promise of early disease detection and individualized therapy, requires new methods for the analysis of clinical specimens. We have developed quantitative fluorescence imaging analysis (QFIA) for accurate, reproducible quantification of proteins in slide-mounted tissues. The method has been validated for the analysis of beta-catenin in archived prostate specimens fixed in formalin. QFIA takes advantage of the linearity of fluorescence antibody signaling for tissue epitope content, a feature validated for beta-catenin in methacarn-fixed prostate specimens analyzed by reverse-phase protein array analysis and QFIA (r = 0.97). QFIA of beta-catenin in formaldehyde-fixed tissues correlated directly with beta-catenin content (r = 0.86). Application of QFIA in a cross-sectional study of biopsies from 42 prostate cancer (PC) cases and 42 matched controls identified beta-catenin as a potential field marker for PC. Receiver operating characteristic plots revealed that beta-catenin expression in the normal-appearing acini of cancerous glands identified 42% (95% confidence intervals, 26-57%) of cancer cases, with 88% (95% confidence intervals, 80-96%) specificity. The marker may contribute to a PC biomarker panel. In conclusion, we report the development and validation of a new method for fluorescence quantification of proteins in archived tissues and its application to archived specimens for an evaluation of beta-catenin expression as a biomarker for PC.  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