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   18339篇
  免费   1529篇
  国内免费   658篇
耳鼻咽喉   71篇
儿科学   452篇
妇产科学   609篇
基础医学   906篇
口腔科学   331篇
临床医学   2508篇
内科学   5023篇
皮肤病学   77篇
神经病学   606篇
特种医学   525篇
外国民族医学   7篇
外科学   1704篇
综合类   2748篇
现状与发展   1篇
预防医学   1064篇
眼科学   24篇
药学   1935篇
  40篇
中国医学   936篇
肿瘤学   959篇
  2024年   51篇
  2023年   393篇
  2022年   702篇
  2021年   984篇
  2020年   837篇
  2019年   755篇
  2018年   705篇
  2017年   751篇
  2016年   750篇
  2015年   730篇
  2014年   1305篇
  2013年   1491篇
  2012年   1074篇
  2011年   1164篇
  2010年   945篇
  2009年   842篇
  2008年   784篇
  2007年   797篇
  2006年   766篇
  2005年   656篇
  2004年   527篇
  2003年   463篇
  2002年   402篇
  2001年   333篇
  2000年   286篇
  1999年   205篇
  1998年   197篇
  1997年   174篇
  1996年   171篇
  1995年   158篇
  1994年   137篇
  1993年   109篇
  1992年   122篇
  1991年   97篇
  1990年   93篇
  1989年   80篇
  1988年   68篇
  1987年   56篇
  1986年   42篇
  1985年   53篇
  1984年   41篇
  1983年   34篇
  1982年   36篇
  1981年   34篇
  1980年   29篇
  1979年   18篇
  1978年   23篇
  1977年   18篇
  1976年   9篇
  1975年   7篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
41.
目的 探讨针对肿瘤化学治疗所呈现的周期性规律,探索胃肠癌患者在化疗期间实施临床路径流程的可行性。方法 选择有病理诊断的晚期胃肠癌患者140例,随机分成实验组和对照组各70例,实验组实施临床路径流程,对照组实施传统流程,比较两组住院天数、医疗费用、医疗质量及患者满意度。结果 实验组患者的住院天数明显缩短(P<0.05),医疗费用明显降低(P<0.05),医疗质量及患者满意度均有较大幅度的提高(P<0.05)。结论 胃肠癌患者化疗期间实施临床路径流程切实可行。  相似文献   
42.
目的:探讨靶基因人类斯钙素1(hSTC—1)在消化道恶性肿瘤患者外周血中的表达以及与肿瘤微转移的关系。方法:采用RT—PCR方法检测69例消化道恶性肿瘤患者外周血中的人类斯钙素1(hSTC—1)mRNA,12例健康成人、4例妊娠期妇女、14例消化道炎症疾病患者,并检测12例消化道恶性肿瘤患者手术中新鲜组织标本中的hSTC—1 mRNA。结果:69例消化道恶性肿瘤患者外周血中,食管癌组hSTC—lmRNA的阳性率为52.9%(9/17例),胃癌组的阳性率为57.7%(15/26例),大肠癌组的阳性率为53.8%(14/26例),消化道恶性肿瘤患者手术中新鲜组织标本的阳性率为100%(12/12例);而健康成人、妊娠期妇女、消化道炎症疾病患者外周血中无1例出现阳性。将肿瘤患者hSTC-1 mRNA检测结果与临床病理结合分析发现:外周血中的hSTC-1m RNA的表达与肿瘤的浸润深度、临床病理分期、淋巴结转移有显著相关性。结论:应用RT—PCR方法检测消化道恶性肿瘤患者外周血中的hSTC—1m RNA具有较高的敏感性和特异性,可成为检测肿瘤外周血微转移的一个新指标。  相似文献   
43.
目的研究17β-雌二醇(17β-E2)对子宫内膜异位症(内异症)患者在位子宫内膜间质细胞β-catenin mRNA和蛋白表达的影响,探讨Wnt/β-catenin信号通路在介导雌激素促进内异症发生发展的作用。方法体外分离培养内异症患者在位子宫内膜间质细胞。用不同浓度17β-E2处理子宫内膜间质细胞48 h;此后选用10-10mol/L 17β-E2处理子宫内膜间质细胞12、24和48 h,逆转录聚合酶链反应(RT-PCR)和免疫印迹法(Western blotting)检测17β-E2处理前后子宫内膜间质细胞β-catenin mRNA和蛋白的表达水平。同法分析雌激素受体拮抗剂ICI182,780(10-6mol/L)对17β-E2促进β-catenin mRNA和蛋白表达的影响。免疫组织化学染色观察17β-E2作用后β-catenin在子宫内膜间质细胞中的定位。结果17β-E2能明显促进内异症患者在位子宫内膜间质细胞β-catenin mRNA和蛋白的表达,并呈剂量和时间依赖性,于10-10mol/L作用48 h最明显。雌激素受体拮抗剂ICI182,780能明显抑制17β-E2对子宫内膜间质细胞β-catenin mRNA和蛋白的表达。免疫组织化学染色发现17β-E2能促进β-catenin在子宫内膜间质细胞核内的表达。结论雌激素可能通过激活Wnt/β-catenin信号通路促进内异症在位子宫内膜的异位种植。  相似文献   
44.
颅脑损伤患者上消化道出血的预防和治疗(附625例报告)   总被引:7,自引:0,他引:7  
目的探讨颅脑损伤后上消化道出血的预防措施及其治疗方法。方法回顾性分析625例颅脑损伤后上消化道出血的病例,在治疗原发伤病基础上,采用止血、制酸、保护胃黏膜等对症处理,同时应用阿托品治疗22例;胃镜下治疗8例;胃次全切除术5例。结果本组病例中,治愈572例,缓解36例,无效5例,死亡12例,其中阿托品治愈20例;胃镜下治愈6例;胃次全切除术治愈4例。结论预防和治疗的重点是消除颅脑损伤病灶和保护胃黏膜,常规处理方案效果满意,简单、经济且安全有效,但必要时应及时使用特殊治疗手段,以迅速控制出血病情。  相似文献   
45.
针刺对血浆骨动素,生长抑素及内皮素的影响及其意义   总被引:14,自引:2,他引:12  
探讨针刺调整调整胃肠功能机理中胃肠激素的作用。方法:对40名健康人对进行针刺胃肠相关穴位试验,随机分4组,即天枢组,巨虚组,非穴位刺激组及空白组。各针刺组均观察针刺前,中,后6次血浆MTL,SS及ET水平的动态变化,空白组不行针刺,只观察同一时间蚋MTL,SS及ET水平的自然波动。  相似文献   
46.
47.
本文阐述了奥美拉唑(Omeprazole)治疗急性上消化道大出血80例与法莫替丁(Famotidine)治疗上消化道大出血50例比较,前者有效率明显高于后者。提示奥美拉唑治疗急性上消化道大出血效果好,无副作用,减少了手术率、死亡率,是一种有效的止血药物。  相似文献   
48.
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   
49.
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   
50.
OBJECTIVE: Many patients with haemorrhoids are investigated because of the fear of missing colorectal cancer (CRC). The aim of this study was to determine whether a primarily clinical approach regarding the need for investigation was safe and did not miss patients with CRC. PATIENTS AND METHODS: Data was collected prospectively on 589 consecutive patients with the principle diagnosis of haemorrhoids at first clinic visit. All had clinical assessment including rigid sigmoidoscopy and were treated by phenol injection or banding. They were categorized for (1) no review unless symptoms persisted -'One Stop SOS' (2) outpatient review or (3) investigation. To check for the development of CRC they were contacted by postal questionnaire or telephone interview with a minimum of one year from diagnosis and treatment. All 589 patients were cross-referenced with the Pathology database and the Hospital Information Services System. RESULTS: Four hundred and sixty-nine (80%) answered the questionnaire; 352 patients (60% of the total group) fell in the 'one stop SOS' outpatient category; 95 (16%) patients were followed up to review response to treatment for large haemorrhoids; 105 (18%) were investigated with barium enema (12%), flexible sigmoidoscopy (4%), colonoscopy (1%) and miscellaneous (1%); 37 (6%) patients were either given a haemorrhoidectomy date or referred on with a different diagnosis. No patients selected for 'one-stop' treatment developed CRC. Five (0.8%) patients were diagnosed with CRC after appropriate investigation was instituted for suspicious symptoms. One patient with distal transverse colon cancer had a delayed diagnosis as she was investigated initially by flexible sigmoidoscopy. CONCLUSION: Most patients with the primary diagnosis of symptomatic haemorrhoids do not need investigation.  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