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   15913篇
  免费   1359篇
  国内免费   65篇
耳鼻咽喉   207篇
儿科学   349篇
妇产科学   234篇
基础医学   2072篇
口腔科学   223篇
临床医学   1738篇
内科学   3425篇
皮肤病学   383篇
神经病学   957篇
特种医学   653篇
外科学   2620篇
综合类   114篇
现状与发展   1篇
一般理论   4篇
预防医学   1362篇
眼科学   521篇
药学   1166篇
中国医学   85篇
肿瘤学   1223篇
  2024年   17篇
  2023年   188篇
  2022年   461篇
  2021年   863篇
  2020年   459篇
  2019年   563篇
  2018年   666篇
  2017年   433篇
  2016年   526篇
  2015年   532篇
  2014年   671篇
  2013年   721篇
  2012年   1149篇
  2011年   1113篇
  2010年   661篇
  2009年   520篇
  2008年   908篇
  2007年   899篇
  2006年   764篇
  2005年   718篇
  2004年   625篇
  2003年   553篇
  2002年   503篇
  2001年   494篇
  2000年   454篇
  1999年   371篇
  1998年   122篇
  1997年   102篇
  1996年   87篇
  1995年   77篇
  1994年   70篇
  1993年   60篇
  1992年   150篇
  1991年   105篇
  1990年   119篇
  1989年   108篇
  1988年   97篇
  1987年   80篇
  1986年   67篇
  1985年   54篇
  1984年   50篇
  1983年   33篇
  1982年   20篇
  1981年   11篇
  1980年   16篇
  1979年   18篇
  1978年   6篇
  1977年   10篇
  1976年   8篇
  1975年   7篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
111.
Lasers in Medical Science - Long-pulsed 1064-nm (LP1064) and 755-nm (LP755) lasers have been demonstrated as effective treatments for leg veins. However, few studies of these treatments on Asian...  相似文献   
112.
BackgroundEstablishing clear risk factors for complications such as urinary tract infection (UTI) after arthroplasty procedures helps guide clinical practice and provides more information to both surgeons and patients. This study aims to assess selected preoperative patient characteristics as risk factors for postoperative UTI after primary total hip and knee arthroplasties (THA and TKA).MethodsThis was a retrospective analysis using current procedural terminology codes to investigate the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database for patients who underwent THA or TKA from 2010 to 2017. Patients were classified for UTI by NSQIP guidelines. Patient samples with all possible covariates were included for multivariate logistic regression analysis and assessed for independent associations.ResultsIn a cohort of 983 identified patients (983 of 119,096; 0.83%): ages 57+ years, preoperative red blood cell (RBC) transfusion, perioperative RBC transfusion, bleeding disorders, operative time 110+ minutes, preoperative steroid use, diabetes, pulmonary comorbidities, body mass index 30+ kg/m2 were independent risk factors for postoperative UTI after THA. In a cohort of 1503 identified patients (1503 of 189,327; 0.8%): ages 60+ years, preoperative RBC transfusion, perioperative RBC transfusion, anemia, platelets less than 150k, preoperative steroid use, diabetes, and body mass index 30+ kg/m2 were independent risk factors for postoperative UTI after TKA. Male sex was associated with a decreased risk of UTI in both THA and TKA.ConclusionThis study provides novel evidence on risk factors associated with the development of UTI after THA or TKA. Clinicians should be aware of risk factors in the manifestation of postoperative UTI after primary THA or TKA procedures.  相似文献   
113.
Pig organ xenotransplantation offers a solution to the shortage of deceased human organs for transplantation. The pathobiological response to a pig xenograft is complex, involving antibody, complement, coagulation, inflammatory, and cellular responses. To overcome these barriers, genetic manipulation of the organ‐source pigs has largely been directed to two major aims—(a) deletion of expression of the known carbohydrate xenoantigens against which humans have natural (preformed) antibodies, and (b) transgenic expression of human protective proteins, for example, complement‐ and coagulation‐regulatory proteins. Conventional (FDA‐approved) immunosuppressive therapy is unsuccessful in preventing an adaptive immune response to pig cells, but blockade of the CD40:CD154 costimulation pathway is successful. Survival of genetically engineered pig kidneys in immunosuppressed nonhuman primates can now be measured in months. Non‐immunological aspects, for example, pig renal function, a hypovolemia syndrome, and rapid growth of the pig kidney after transplantation, are briefly discussed. We suggest that patients on the wait‐list for a deceased human kidney graft who are unlikely to receive one due to long waiting times are those for whom kidney xenotransplantation might first be considered. The potential risk of infection, public attitudes to xenotransplantation, and ethical, regulatory, and financial aspects are briefly addressed.  相似文献   
114.
BackgroundOperative experience with an appropriate degree of supervised autonomy is critical to resident training. Progressively greater intraoperative entrustment has been associated with gradually higher levels of resident autonomy. This study attempts to identify consistently observed intraoperative behaviors that are linked with higher resident entrustment.MethodsThis qualitative study analyzed observational notes recorded by trained raters who provided entrustment scores for 204 surgical cases at Michigan Medicine from 2015 to 2017. Notes were coded in NVivo12. Thematic analysis was used to identify themes and patterns within the data.ResultsThe analysis generated 144 codes. Codes were clustered into 10 themes. These themes manifested differently in intraoperative behaviors strongly associated with high entrustment versus low entrustment.ConclusionThis study demonstrates key differences in intraoperative behaviors exhibited by residents and faculty in high and low entrustment interactions. Awareness of behaviors that enhance entrustment can help faculty augment resident learning and enable higher resident operative autonomy.  相似文献   
115.
BackgroundDuodenal complications of necrotizing pancreatitis (NP) are challenging and understudied. We sought to characterize the demographics and clinical course of NP patients with duodenal complications.MethodsSingle institution retrospective review of 687 NP patients treated from 2005 to 2018.ResultsDuodenal complications developed in 40 (6%) patients including fistula in 11 (2%) and stricture in 29 (4%) patients. Patients with duodenal complications had increased computed tomography severity index (CTSI), degree of glandular necrosis, organ failure, infected necrosis, and disease duration. Mortality from NP was increased in patients with duodenal fistula (36%) compared to patients with duodenal stricture (7%) and patients without duodenal complications (9%). Surgical management of duodenal complications was required in 9/11 (82%) patients with fistula and 17/29 (59%) patients with stricture.ConclusionsDuodenal complications occurred in 6% of necrotizing pancreatitis patients. Sixty five percent of patients with duodenal complications required surgical correction. Duodenal fistula was associated with increased mortality.  相似文献   
116.
117.
118.
BackgroundAppendicitis is a common pediatric surgical condition, comprising a large burden of healthcare costs. We aimed to determine if prolonged operative times were associated with increased 30-day complication rates when adjusting for pre-operative risk factors.MethodsPatients <18 years old, diagnosed intraoperatively with acute uncomplicated appendicitis and undergoing laparoscopic appendectomy were identified from the NSQIP-P 2012–2018 databases. The primary outcome, “infectious post-operative complications”, is a composite of sepsis, deep incisional surgical site infections, wound disruptions, superficial, and organ space infections within 30-days of the operation. Secondary outcomes included return to the operating room and unplanned readmissions within 30 days. Logistic regression models were used to assess associations between operative time and each outcome. A Receiver Operating Characteristic (ROC) curve was generated from the predicted probabilities of the multivariate model for infectious post-operative complications to examine operative times.ResultsBetween 2012 and 2018, 27,763 pediatric patients with acute uncomplicated appendicitis underwent a laparoscopic appendectomy. Over half the population was male (61%) with a median operative time of 39 min (IQR 29–52 min). Infectious post-operative complication rate was 2.8% overall and was highest (8%) among patients with operative time ≥ 90 min (Fig. 1). Unplanned readmission occurred in 2.9% of patients, with 0.7% returning to the operating room. Each 30-min increase in operating time was associated with a 24% increase in odds of an infectious post-operative complication (OR=1.24, 95% CI=1.17–1.31) in adjusted models. Operative time thresholds predicted with ROC analysis were most meaningful in younger patients with higher ASA class and pre-operative SIRS/Sepsis/Septic shock. Longer operative times were also associated with higher odds of unplanned readmission (OR=1.11, 95% CI=1.05–1.18) and return to the operating room (OR=1.13, 95% CI=1.02–1.24) in adjusted models.ConclusionThere is a risk-adjusted association between prolonged operative time and the occurrence of infectious post-operative complications. Infectious postoperative complications increase healthcare spending and are currently an area of focus in healthcare value models. Future studies should focus on addressing laparoscopic appendectomy operative times longer than 60 min, with steps such as continuation of antibiotics, shifting roles between attending and resident surgeons, and simulation training.Level of EvidenceLevel III, retrospective comparative study  相似文献   
119.
BackgroundThyroid surgeons are offering their patients less aggressive diagnostic and therapeutic management strategies for thyroid nodules and low-risk thyroid cancer in an effort to decrease overdiagnosis and overtreatment of indolent disease. Explaining the rationale for less aggressive management plans requires physicians to be effective communicators. We aimed to assess the communication skills of thyroid surgeons with the Makoul Communication Assessment Tool and to identify risk factors for poor communication.MethodsNew adult patients with thyroid nodules or thyroid cancer presenting to a single tertiary-referral endocrine surgery clinic were enrolled from July 2018 through December 2019. Patients were administered the Communication Assessment Tool immediately after their clinical encounter. Outlier communication scores were identified, and clinical characteristics were compared between outlier and nonoutlier groups.ResultsA total of 107 patients completed the Communication Assessment Tool. Mean (standard deviation) total and top box scores were 67 (6) and 86% (29%), respectively. Twenty-five patients (23%) were in the low-outlier group, defined by a total score below 67.5/70 or top box score below 82.25%. Other race and non-Hispanic patients (versus white race) were more likely low outliers (odds ratio 3.58, P = .048). The lowest scoring Communication Assessment Tool item overall was “the doctor encouraged me to ask questions” (78.5% top box).ConclusionWe found communication to be perceived as excellent in the majority of patients; however, an opportunity for improvement was identified in 29% of participants. Significant differences in race and ethnicity between low outlier and nonoutlier communication score patients were observed, which warrants additional investigation. These findings support the utility of the Communication Assessment Tool in studying the effectiveness of communication improvement initiatives.  相似文献   
120.
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