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   4064篇
  免费   382篇
  国内免费   46篇
耳鼻咽喉   52篇
儿科学   129篇
妇产科学   184篇
基础医学   613篇
口腔科学   71篇
临床医学   389篇
内科学   891篇
皮肤病学   29篇
神经病学   246篇
特种医学   217篇
外科学   580篇
综合类   105篇
一般理论   3篇
预防医学   213篇
眼科学   159篇
药学   254篇
中国医学   20篇
肿瘤学   337篇
  2023年   22篇
  2022年   48篇
  2021年   71篇
  2020年   66篇
  2019年   85篇
  2018年   115篇
  2017年   88篇
  2016年   75篇
  2015年   107篇
  2014年   120篇
  2013年   177篇
  2012年   222篇
  2011年   232篇
  2010年   169篇
  2009年   142篇
  2008年   198篇
  2007年   200篇
  2006年   246篇
  2005年   221篇
  2004年   237篇
  2003年   200篇
  2002年   200篇
  2001年   190篇
  2000年   117篇
  1999年   116篇
  1998年   76篇
  1997年   67篇
  1996年   52篇
  1995年   58篇
  1994年   53篇
  1993年   37篇
  1992年   49篇
  1991年   51篇
  1990年   36篇
  1989年   46篇
  1988年   44篇
  1987年   37篇
  1986年   38篇
  1985年   24篇
  1984年   18篇
  1983年   19篇
  1982年   17篇
  1981年   12篇
  1980年   13篇
  1979年   14篇
  1978年   7篇
  1977年   10篇
  1976年   8篇
  1975年   14篇
  1974年   6篇
排序方式: 共有4492条查询结果,搜索用时 31 毫秒
41.
42.
BACKGROUND: Embedded fetal bone after surgical termination of midtrimester pregnancy is a recognized complication. Most cases occur in the uterine cavity; however, this case demonstrates that a cervicovaginal fistula can be caused by embedment of bone in the cervical canal. CASE: A 19-year-old girl presented with persistent smelly vaginal discharge 4 years after surgical pregnancy termination. On examination she had a cervicovaginal fistula with embedded fetal bone that was subsequently removed surgically. CONCLUSION: Cervicovaginal fistula can be a complication of surgical termination of midtrimester pregnancy as fetal bones can become embedded in the cervical canal during removal.  相似文献   
43.
This study focused on the encapsulation of vancomycin(VAN) into liposomes coated with a red blood cell membrane with a targeting ligand, daptomycin–polyethylene glycol–1,2-distearoyl-sn-glycero-3-phosphoethanolamine, formed by conjugation of DAPT and Nhydroxysuccinimidyl-polyethylene glycol-1,2-distearoyl-sn-glycero-3-phosphoethanolamine.This formulation is capable of providing controlled and targeted drug delivery to the bacterial cytoplasm. We performed MALDI-TOF, NMR and FTIR analyses to conf...  相似文献   
44.
BACKGROUND: The role of laparoscopic cholecystectomy (LC) in acute cholecystitis remains controversial. The aim of the present study was to determine the incidence, clinicopathological characteristics, and outcome of patients with gallbladder cancer presenting with acute cholecystitis. METHODS: We performed a retrospective analysis of patients with gallbladder cancer who presented with acute cholecystitis and were treated at the public hospitals in Hong Kong between 1998 and 2002. RESULTS: Among 2,700 patients with acute cholecystitis managed with cholecystectomy (1,347 open and 1,353 LC), 63 patients (2.3%) were found to have gallbladder cancer. There were 44 women and 19 men with a mean age of 74.7 (+/-12.8) years. Adenocarcinoma (90.5%) was the most common cancer. The overall median survival was 5 months (95% CI = 2.6-7.4). The 5-year survival rate was 20.8%. Laparoscopic cholecystectomy was attempted in 11 patients and was completed successfully in six of them. There was no difference between the LC and open groups in the complication rate, hospital mortality rate, or survival rate. CONCLUSIONS: In the ethnic Chinese population of Hong Kong, the incidence of gallbladder cancer presenting with acute cholecystitis is higher than the same finding in patients undergoing elective cholecystectomy for cholelithiasis. Long-term survival is possible because such patients may be diagnosed at an early stage of the disease.  相似文献   
45.
46.
Acute otomastoiditis and its complications: role of CT   总被引:2,自引:0,他引:2  
Acute bacterial (suppurative) otomastoiditis responds to antibiotic treatment; radiologic study is required only when there is clinical suggestion of coalescent mastoiditis, intracranial complications, or an underlying chronic disease. Computed tomography (CT) is the method of choice for evaluating otogenic intra- or extra-cranial complications. CT scans can show stages of disease progression when infection has spread by way of soft tissue, blood, and bone pathways into the dural venous sinuses, meninges, labyrinth, facial nerves, epidural and other intracranial spaces. When there is clinical suggestion of acute coalescent mastoiditis, a CT scan of the temporal bone can confirm the presence of rarefying osteitis, coalescence of the air cells, and subperiosteal abscess.  相似文献   
47.
48.
49.
The human T-lymphotropic virus type III (HTLV-III) is the primary cause of the acquired immunodeficiency syndrome (AIDS) and related disorders (ARC). Prior studies have reported that nearly all symptomatic patients with AIDS or ARC manifest antibody to HTLV-III. This observation has engendered efforts to screen for HTLV-III, especially prior to blood donation, with assays for antibody to HTLV-III. We report the first two cases, one with AIDS and one with ARC, that are HTLV-III virus positive but antibody negative. Accurate diagnosis of HTLV-III infection in some cases may require direct virus culture or tests for antigen. In addition, lack of HTLV-III antibody may indicate an atypical clinical course of AIDS.  相似文献   
50.
BACKGROUND: This was a prospective study to evaluate the effect of radical external irradiation on inner ear function after treatment of nasopharyngeal carcinoma. METHODS: Pure tone audiograms were performed at regular intervals before, after, and up to 4.5 years following completion of radiotherapy. RESULTS: Two hundred ninety-four patients (526 ears) were included. Within 3 months after radiotherapy, deterioration of bone conduction threshold at 4 kHz and pure tone average (average of 0.5 kHz, 1 kHz, and 2 kHz) were noted in 164 ears (31%) and 75 ears (14%), respectively. Patients older than 50 years and ears with threshold below 60 dB at 4 kHz before radiotherapy were significant factors (p < 0.01 and p < 0. 001) associated with a 4 kHz loss. In 40% of these ears, recovery was evident at 2 years. With follow-up for 4.5 years, the probability of significant threshold deterioration increased with time. CONCLUSION: Sensorineural hearing loss started soon after radiotherapy. Early changes could be reversible while the probability of persistent hearing loss continued to increase.  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