首页 | 官方网站   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   26531篇
  免费   2017篇
  国内免费   665篇
医药卫生   29213篇
  2023年   478篇
  2022年   647篇
  2021年   1476篇
  2020年   1056篇
  2019年   1021篇
  2018年   1013篇
  2017年   942篇
  2016年   924篇
  2015年   995篇
  2014年   1764篇
  2013年   2058篇
  2012年   1406篇
  2011年   1585篇
  2010年   1210篇
  2009年   1180篇
  2008年   1176篇
  2007年   1054篇
  2006年   955篇
  2005年   866篇
  2004年   749篇
  2003年   657篇
  2002年   555篇
  2001年   510篇
  2000年   434篇
  1999年   373篇
  1998年   344篇
  1997年   293篇
  1996年   265篇
  1995年   234篇
  1994年   259篇
  1993年   223篇
  1992年   227篇
  1991年   198篇
  1990年   164篇
  1989年   142篇
  1988年   173篇
  1987年   148篇
  1986年   156篇
  1985年   227篇
  1984年   167篇
  1983年   134篇
  1982年   145篇
  1981年   107篇
  1980年   103篇
  1979年   75篇
  1978年   68篇
  1977年   69篇
  1976年   62篇
  1975年   30篇
  1974年   28篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
PurposeIn 2018, The Journal of Vascular and Interventional Radiology (JVIR) updated its guidelines regarding periprocedural antibiotics. However, some institutions are slower to adopt these new guidelines. Additionally, antibiotic-resistant bacteria and sepsis are serious concerns due in part to incorrect usage of antibiotics. The purpose of this study is to assess institutional adherence to 2018 JVIR guidelines for the purpose of improving antibiotic stewardship.Materials and methodsA total of 800 cases over a 10-month time period were retrospectively identified and charted following the release of guidelines. Inclusion criteria for the study were adults aged 21 years or older undergoing mediport placement, tunneled central line (TCL) placement, nephrostomy tube exchange, percutaneous biliary drain, or cholecystostomy tube exchange. Exclusion criteria included immunocompromised and pregnant individuals as 2018 guidelines may not fit these patient populations. Guideline adherence for each procedure was recorded as a percentage; the timing of the antibiotic usage was also recorded and compared to the guidelines (within 60 minutes before incision).ResultsIn total, 49 mediport placements, 118 tunneled central line placements – 44 hemodialysis (HD) catheters and 74 nonhemodialysis (non-HD) catheters, 100 nephrostomy exchanges, and 82 biliary tube exchanges were included. Antibiotics were used in 83.6% (41/49) of mediport patients, 11.3% (5/44) of non-HD TCL patients, 20.5% (15/74) of HD TCL patients, 55% (55/100) nephrostomy tube changes, and 65.4% (55/84) of biliary or cholecystostomy tube exchanges. Out of those given prophylaxis, guideline-recommended antibiotics were used in 100% (41/41) of mediport, 100% (20/20) of TCL (both HD and non-HD catheters), 9% (5/55) of nephrostomy tube exchanges, and 1.8% (1/55) of biliary tube exchanges. Guideline-recommended timing was followed in 75.3% across all cases (ranging from 72.2% in mediports to 79.3% in biliary exchanges).ConclusionThis study of antibiotic practices at a single university-based academic institution revealed that antibiotic usage is not fully up to date with 2018 guidelines. For mediports, non-HD TCL placements, and nephrostomy tube exchanges, institutional changes should be made to reduce periprocedural antibiotic use, as antibiotics are no longer recommended for these procedures. For HD TCL and biliary exchanges, proper adherence to recommended prophylactic antibiotics should be followed. In addition, education about the correct antibiotic timing should be emphasized to increase compliance with guidelines.  相似文献   
3.
4.
5.
6.
7.
8.
IntroductionThe treatment of papillary thyroid microcarcinoma remains controversial. Central lymph node metastasis is common in papillary thyroid microcarcinoma and it is an important consideration in treatment strategy selection.ObjectiveThe aim of this study was to investigate clinicopathologic risk factors and thyroid nodule sonographic characteristics for central lymph node metastasis in papillary thyroid microcarcinoma.MethodsWe retrospectively reviewed the data of 599 papillary thyroid microcarcinoma patients who underwent surgery from 2005 to 2017 at a single institution. Univariate and multivariate analyses were used to identify the clinicopathologic factors and preoperative sonographic features of central lymph node metastasis. A receiver-operating characteristic, ROC curve analysis, was performed to identify the efficacy of ultrasonographic features in predicting central lymph node metastasis. A nomogram based on the risk factors was established to predict central lymph node metastasis.ResultsThe incidence of central lymph node metastasis was 22.4%. The univariate and multivariate analyses suggested that gender, age, multifocality, extrathyroidal invasion, and lateral lymph node metastasis were independent risk factors for central lymph node metastasis. The univariate and multivariate analyses revealed that nodular shape, margin, and calcification were independently associated with central lymph node metastasis. The ROC curve analysis revealed that the combination of shape, margin and calcification had excellent accuracy in predicting central lymph node metastasis. The nomogram was developed based on the identified risk factors for predicting central lymph node metastasis, and the calibration plot analysis indicated the good performance and clinical utility of the nomogram.ConclusionsCentral lymph node metastasis is associated with male gender, younger age (<45 years), extrathyroidal invasion, multifocality and lateral lymph node metastasis in papillary thyroid microcarcinoma patients. The ultrasongraphic features, such as irregular shape, ill-defined margin and calcification, may improve the efficacy of predicting central lymph node metastasis. Surgeons and radiologists should pay close attention to the patients who have these risk factors. The nomogram may help guide surgical decision making in papillary thyroid microcarcinoma.  相似文献   
9.
10.
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-23

京公网安备 11010802026262号