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   14218篇
  免费   1111篇
  国内免费   472篇
耳鼻咽喉   152篇
儿科学   385篇
妇产科学   50篇
基础医学   964篇
口腔科学   190篇
临床医学   2000篇
内科学   2907篇
皮肤病学   36篇
神经病学   685篇
特种医学   482篇
外国民族医学   6篇
外科学   1940篇
综合类   2135篇
现状与发展   1篇
预防医学   817篇
眼科学   25篇
药学   1431篇
  26篇
中国医学   625篇
肿瘤学   944篇
  2024年   55篇
  2023年   301篇
  2022年   599篇
  2021年   770篇
  2020年   643篇
  2019年   585篇
  2018年   576篇
  2017年   557篇
  2016年   559篇
  2015年   564篇
  2014年   1062篇
  2013年   1109篇
  2012年   801篇
  2011年   894篇
  2010年   736篇
  2009年   633篇
  2008年   635篇
  2007年   587篇
  2006年   578篇
  2005年   451篇
  2004年   408篇
  2003年   339篇
  2002年   299篇
  2001年   267篇
  2000年   219篇
  1999年   158篇
  1998年   150篇
  1997年   130篇
  1996年   135篇
  1995年   132篇
  1994年   107篇
  1993年   88篇
  1992年   98篇
  1991年   78篇
  1990年   72篇
  1989年   64篇
  1988年   46篇
  1987年   53篇
  1986年   35篇
  1985年   36篇
  1984年   29篇
  1983年   18篇
  1982年   27篇
  1981年   27篇
  1980年   16篇
  1979年   19篇
  1978年   13篇
  1977年   11篇
  1976年   7篇
  1975年   7篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
Omeprazole is a substituted benzimidazole that causes dose-dependent intracellular inhibition of gastric acid secretion in humans. This double-blind study examined the effect of omeprazole in decreasing gastric acidity and gastric residual volume in outpatient adults. Unpremedicated outpatients, ASA I-III, 18 years or older (n = 17), were randomly assigned to receive omeprazole 80 mg, or placebo by mouth the night before scheduled elective outpatient surgery. The patients were fasted for 8 h prior to surgery. After the patient was anesthetized, an orogastric tube was inserted with proper placement verified by auscultation for gastric sounds. Gastric residual contents were withdrawn into a Luken's trap, and pH was then determined and gastric volume indexed to weight (ml.kg-1). Data were analyzed by a t-test, with P less than 0.05 considered statistically significant. Patient characteristics of both groups were similar. There was a statistically significant difference between the two groups for pH (P = 0.02), but not between the two groups for gastric volume indexed to weight (P = 0.07).  相似文献   
42.
The author describes his surgical approach to the problems of the aging upper arm and elbow region. Surgery at an appropriate age can prevent the progressive wrinkling of the elbow which is further aggravated by aging of the upper arm. The author's operation is aimed at correcting both portions of the arm anatomy at the same time.  相似文献   
43.
OBJECTIVE: Surgery for Crohn's disease (CD) is associated with a high recurrence rate and quality of life (QOL) in these patients is controversial. The aim of this study was to assess QOL in patients after laparoscopic and open surgery for CD by two different validated instruments, a generic nonspecific score and a specific gastrointestinal QOL index. PATIENTS AND METHODS: Patients with CD who underwent elective laparoscopic or open ileocaecal resection with primary anastomosis between 1992 and 2000 were followed for recurrence and surgery-related complications. QOL was assessed by the SF-36 Health Survey containing a mental (MCS) and a physical (PCS) component summary score and by the Gastrointestinal Quality of Life Index (GIQLI) developed by Eypasch. RESULTS: Thirty-seven patients with a mean age of 48.8 +/- 18.4 years including 23 females and 14 males were evaluated at a mean follow-up of 42.6 +/-25.8 months (minimum of 8 months). Twenty-one (57%) patients underwent laparoscopic resection and 16 (43%) open surgery. Both groups were well matched for age, gender, ASA class and body mass index. Fourteen (38%) patients developed recurrent disease and 3 (8%) had postoperative incisional hernias. Overall, QOL scores were 103 +/- 26.8 for the GIQLI, 47.2 +/- 11.8 for the PCS, and 49.2 +/- 11.5 for the MCS. The GIQLI correlated well with the SF36, correlation coefficient = 0.68 for GIQLI vs PCS (95% CI, 0.41,0.95) and 0.67 for GIQLI vs MCS (95%CI, 0.39, 0.95), respectively. When compared to the general US population, mean GIQLI scores (-13.8, P = 0.002) and mean PCS scores (-4.7, P = 0.001) were significantly lower in these patients than in healthy individuals. In a multivariate analysis of impact factors on QOL, recurrence within the follow-up period was the single significant determinant reducing the PCS (-35.1, P = 0.026) and the GIQLI (-36.1, P = 0.018). CONCLUSION: QOL is significantly reduced in patients with CD at long-term follow-up after both laparoscopic and open surgery. Recurrence is the only factor adversely affecting QOL of CD patients in remission irrespective of the operative technique applied.  相似文献   
44.
A 52‐year‐old Japanese woman who presented with gastrointestinal (GI) bleeding underwent a proximal gastrectomy for a gastrointestinal stromal tumor (GIST) with a foveolar hyperplasia at the apex of the tumor, 4.5 cm in size, located in the upper body of the stomach. Although GIST are often asymptomatic and are found only incidentally, clinical symptoms such as bleeding, abdominal pain, or obstruction, occasionally lead to a premorbid diagnosis. When submucosal tumors present GI bleeding, the source of the bleeding usually is an ulceration of the mucosa over the tumor. However, in the present study, it was thought that the bleeding originated from the region of foveolar hyperplasia.  相似文献   
45.
Attempts have been made to culture the mucosa from various parts of the gastrointestinal tract. In this study, using an explant culture method, epithelial cells have been successfully cultured from all major regions of the gastrointestinal tract. The success rate, as judged by outgrowth of epithelial cells for at least 4 weeks, varied with the tissue studied with 19/50 colonic biopsies, 5/11 small intestinal biopsies, 9/12 stomach biopsies and 42/47 gallbladder biopsies yielding outgrowth of epithelial cells. Differentiation of the epithelial cells along the mucus cell pathway could be demonstrated on the monolayer cultures using Periodic acid Schiff or Alcian blue staining. Because the cultures were very heterogeneous and many morphological cell types were present in most cultures, differentiation along the other known differentiation pathways of the gastrointestinal mucosa, such as development of absorptive cells and endocrine cells, could not be excluded.
The problem of bacterial contamination, which has hindered previous studies on tissue from these sites, was overcome by decontaminating the biopsy by soaking in dilute sodium hypochlorite (0.04%).  相似文献   
46.
内眦赘皮与重睑成形同期手术的一种新方法   总被引:12,自引:1,他引:11  
目的 探索适合同时行重睑成形术和内眦赘皮矫正术的新方法。方法 根据内眦赘皮深部眼轮匝肌结构上的异常特点,遵循内眦赘皮的上睑(倒向性内眦赘皮除外)内侧睑缘处皮肤短缺和尽量减少局部皮肤瘢痕的原则,设计适合同时行重睑成形术的新内眦赘皮矫正术(反Stallard法)。结果 临床应用86例,进行了为期6个月以上的随访,结果所有患者的重睑为稳定性平行型重睑,内眦已完全或大部分开大,手术效果满意。结论 此内眦赘皮矫正术能够充分矫正内眦部结构上的异常,而且适合与重睑成形术同期施行,是一种效果稳定,结果满意的术式。  相似文献   
47.
目的:验证美宝胃肠胶囊(GIC)治疗常见的上消化道疾病的治疗效果。方法:选择门诊具有上消化道症状,临床病例共60例,经内镜确诊的十二指肠球炎、十二指肠球霜样溃疡等15例,溃疡病15例,作为治疗组,分别单独服用美宝胃肠胶囊及服用美宝胃肠胶囊加用质子泵抑制剂(包括其他抑酸剂);对照组则为单独服用胃肠黏膜保护剂麦滋林-S 15例,及服用麦滋林-S加用质子泵抑制剂(包括其他抑酸剂)15例;疗程完成后治疗组及对照组均复查胃镜,记录镜下溃疡愈合或炎症改变情况。结果:治疗1组(美宝胃肠胶囊组)的治愈率为80.0%,治疗2组(美宝胃肠胶囊组十质子泵抑制剂)的治愈率为73.3%,对照1组和对照2组均为66.7%,且副作用小。结论:美宝胃肠胶囊是既能治疗上消化道疾病,又少有毒副作用,价格合理的药物,值得进一步观察、研究、推广。  相似文献   
48.
Females are disproportionately affected by constipation, which is often aggravated during pregnancy. Bowel function also changes during the luteal phase of the menstrual cycle. The aim was to compare the effects of acute administration of female sex steroids on gastric emptying, small bowel transit and colonic transit in healthy postmenopausal subjects. A second aim was to determine whether withdrawal of the hormones was associated with a change in transit. Forty-nine postmenopausal females were randomized to receive for 7 days 400 mg day(-1) micronized progesterone, 0.2 mg day(-1) oestradiol, combination of the two, or placebo. Treatment groups were balanced on age. Participants underwent whole gut transit measurement by scintigraphy using a 99m-labeled technetium-egg meal and 111-labeled indium-charcoal via a delayed-release capsule. Transit measurement was repeated after withdrawal of the study medications. The primary endpoints were ascending colon (AC) emptying half-life time (t1/2) and colonic geometric centre (GC) at 24 h. Secondary analysis variables were GC at 4 and 48 h, gastric emptying t1/2 and colonic filling at 6 h. There was a significant overall effect of progesterone on colonic transit with shorter AC emptying t1/2 and significantly greater colonic GC at 48 h. No transit endpoints were altered by oestradiol or combined hormonal treatment relative to placebo. Oestradiol and progesterone resulted in looser stool consistency. Withdrawal of the hormone supplement was not associated with significant alteration in transit. Micronized progesterone does not retard colonic transit in postmenopausal females.  相似文献   
49.
99TCm-RBC显像在下消化道出血诊断中的应用   总被引:1,自引:0,他引:1  
目的 研究 99TCm-RBC显像诊断下消化道出血的临床价值。方法 对 2 5例下消化道出血患者行 99TCm-RBC显像 ,并与手术及病理检查结果作比较。结果 99TCm-RBC显像诊断下消化道出血阳性率为 80 .0 %,定位诊断率为 68.0 %,特异性为 85 .0 %。结论99TCm-RBC显像可作为下消化道出血诊断及定位的一种有效方法。  相似文献   
50.
松解及眼轮匝肌下脂肪垫转移充填矫正重睑术后睑粘连畸形   总被引:10,自引:0,他引:10  
目的矫正重睑成形术后的上睑粘连、重睑较宽、眼睑上抬受限等畸形。方法另设计重睑线,彻底松解眼睑内的组织粘连,释放眶隔内脂肪及转移眼轮匝肌下脂肪垫充填。结果两年来为32例重睑成形术后畸形者用此法治疗得到满意效果。结论此方法简单易行,效果好。  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