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   12481篇
  免费   816篇
  国内免费   498篇
耳鼻咽喉   32篇
儿科学   136篇
妇产科学   25篇
基础医学   492篇
口腔科学   194篇
临床医学   1684篇
内科学   2318篇
皮肤病学   440篇
神经病学   193篇
特种医学   453篇
外科学   1464篇
综合类   2534篇
预防医学   472篇
眼科学   362篇
药学   1646篇
  20篇
中国医学   1237篇
肿瘤学   93篇
  2024年   26篇
  2023年   231篇
  2022年   279篇
  2021年   407篇
  2020年   366篇
  2019年   300篇
  2018年   283篇
  2017年   374篇
  2016年   386篇
  2015年   385篇
  2014年   821篇
  2013年   986篇
  2012年   805篇
  2011年   830篇
  2010年   671篇
  2009年   580篇
  2008年   564篇
  2007年   556篇
  2006年   556篇
  2005年   528篇
  2004年   411篇
  2003年   365篇
  2002年   311篇
  2001年   373篇
  2000年   289篇
  1999年   236篇
  1998年   236篇
  1997年   200篇
  1996年   188篇
  1995年   173篇
  1994年   161篇
  1993年   115篇
  1992年   109篇
  1991年   94篇
  1990年   92篇
  1989年   78篇
  1988年   86篇
  1987年   85篇
  1986年   45篇
  1985年   38篇
  1984年   31篇
  1983年   28篇
  1982年   18篇
  1981年   20篇
  1980年   17篇
  1979年   13篇
  1978年   12篇
  1977年   12篇
  1976年   11篇
  1975年   6篇
排序方式: 共有10000条查询结果,搜索用时 16 毫秒
91.
目的探讨胆汁返流与幽门区局部神经递质一氧化氮的变化对应激性溃疡发病的影响及可能的机理。方法采用冷束缚应激方法复制应激性溃疡的动物模型,将60只成年SD大鼠分为两部分,第1部分:对照组10只,溃疡组30只,用于观测影响应激性溃疡发生的相关因素;第2部分:左旋硝基精氨酸甲酯(L—NAME)预处理组10只(L—NAME组),生理盐水预处理组10只(生理盐水组),用于观测幽门区局部一氧化氮含量变化对其他因素的影响。分别检测各组胃内胆汁酸浓度、胃黏膜溃疡指数(Guth评分)以及胃内pH值,用生化试剂盒检测幽门区一氧化氮的含量。结果溃疡组应激结束后1h幽门区一氧化氮含量达到峰值(P〈0.01),应激结束后2h胃内胆汁酸浓度和pH值均达到峰值(P〈0.01),应激结束后4h胃内溃疡指数达到峰值(P〈0.01)。L-NAME组的胃内胆汁酸浓度、溃疡指数及一氧化氮含量较生理盐水组显著降低(P〈0.01,P〈0.05),而胃内pH值的差异无统计学意义(P〉0.05)。幽门区一氧化氮含量与胆汁酸浓度呈正相关(r=0.715,F=12.55,P=0.017)。结论幽门区一氧化氮含量变化与胆汁的返流量之间存在正相关关系,而L—NAME的幽门区局部干预使幽门区一氧化氮含量减少,幽门松弛程度降低,胆汁返流量也随之减少,进而降低溃疡指数,起到保护胃黏膜的作用。  相似文献   
92.
Background and aims The aim of this study is to evaluate the predictive accuracy of different scoring systems on surgery for perforated peptic ulcer referred to an academic department of general surgery in a tertiary reference center. Patients and methods Seventy-five consecutive patients (Male/female ratio = 64:11; mean age, 44 years; range, 16–85) with perforated peptic ulcer disease were investigated. Disease severity scores and mortality predictions were calculated using the collected data during admission. Discrimination and calibration characteristics of each system, namely, the acute physiology and chronic health evaluation II and III, the simplified acute physiology score II, and the mortality probability models (MPM) II, were determined by using the area under receiver operating characteristics curve and the Hosmer–Lemeshow goodness-of-fit test, respectively. Results Among the 75 patients included, there were eight (10.6%) mortalities. All systems had a reliable power of discrimination and calibration. Among the systems tested, MPM II was the best performing as far as discrimination and calibration characteristics were considered. The parameters of MPM II system that were related to systemic perfusion of the patient were significantly positive in patients who died compared to those who survived. Conclusions MPM II that predicted mortality at admission is better than the other systems in predicting mortality. Results also indicate the importance of maintenance of systemic perfusion of the patient at the early phases of peptic ulcer perforation.  相似文献   
93.
腹腔镜与开腹胃十二指肠溃疡穿孔修补术的对比研究   总被引:4,自引:0,他引:4  
目的:比较腹腔镜与开腹胃十二指肠溃疡穿孔修补术的疗效。方法:回顾分析我院确诊为胃十二指肠溃疡穿孔52例患者的临床资料,其中28例行腹腔镜胃十二指肠溃疡穿孔修补术(腹腔镜组),24例行开腹胃十二指肠溃疡穿孔修补术(开腹组),比较两组手术时间、术中出血量、并发症发生率、术后肠道功能恢复时间、术后体温及住院时间。结果:腹腔镜组与开腹组手术时间分别为(78.75±25.178)min和(97.50±26.029)m in(P<0.05),术中出血量分别为(43.21±12.488)ml和(77.50±21.518)m l(P<0.001),并发症分别为3例和8例(P<0.05),术后体温>38℃分别为5例、11例,术后肠蠕动恢复时间分别为(2.33±0.816)d和(3.75±1.035)d(P<0.001),术后住院分别为(6.83±1.169)h和(10.00±1.309)h(P<0.001)。结论:胃十二指肠溃疡穿孔患者行腹腔镜手术与开腹手术一样安全,且具有创伤小、康复快、住院时间短等优点。  相似文献   
94.
目的 评价腹腔镜下修补治疗十二指肠球部前壁溃疡穿孔的临床应用价值。方法 对我院2003年1月~2004年12月收治的42例青年十二指肠溃疡穿孔病例随机分组,20例接受腹腔镜下修补治疗,22例接受传统开腹修补。结果 两组术后胃肠功能恢复情况、术后使用镇痛药、平均住院时间差异均有显著性(P〈0.05),两组术后均无出血、中转开腹、再穿孔等并发症。结论 腹腔镜下修补治疗青年十二指肠球部前壁溃疡穿孔临床安全可行,应该作为首选方法在临床上推广应用。  相似文献   
95.
十二指肠溃疡生活事件及社会支持的对照研究   总被引:8,自引:1,他引:7  
目的 探讨十二指肠溃疡与生活事件及社会支持的关系。方法 采用生活事件量表(LES),社会支持评定量表(SSRS)对十二指肠溃疡患者(58例)与健康对照(67例)进行问卷测试与评价分析。结果 十二指肠溃疡患者在生活事件里正性刺激量,负性刺激量和总刺激量都明显高于健康对照组,十二指肠溃疡患者受到的主观支持比一般人群多;而客观支持比一般人群少,但十二指肠溃疡患者受到的总支持量并不比一般人多,而且,十二指肠溃疡患者对支持的利用度也不比一般人高。结论 十二指肠溃疡患者有明显的生活事件和不足的社会支持,对生活事件的刺激尤为敏感。  相似文献   
96.
We herein report the case of a 53-year-old man with a nonspecific acute colonic ulcer whose liver function deteriorated after he had undergone hepatectomy. He was referred to our hospital for a hepatoma caused by hepatitis B virus and a right hemihepatectomy was performed. His liver function was poor after the operation, and minor complications such as pleural effusion and biliary fistula developed. A large amount of melena was seen 29 days after the hepatectomy and he developed hemorrhagic shock. Superior mesenteric arteriography revealed pooling of blood in both the hepatic flexure of the ascending colon and the cecum. An emergency right hemicolectomy was performed. There was a 5 x 1-mm ulcer 18 cm distal to the ileocecal valve. Numerous erosions were observed to be scattered throughout the colonic mucosa. The patient recovered slowly and was discharged 6 months after the hepatectomy. This is the first report of an acute colonic ulcer that could have been caused by liver dysfunction.  相似文献   
97.
[目的]评价羟苯磺酸钙治疗糖尿病性皮肤溃疡的疗效和安全性.[方法]采用双盲临床随机对照试验.76例糖尿病性皮肤溃疡患者,随机分为试验组和对照组.试验组38例服用羟苯磺酸钙;对照组38例服用安慰剂维生素C;疗程8周.[结果]试验组溃疡愈合的速度与程度均明显优于对照组.总有效率试验组为94.74%,对照组为52.63%,两者之间有显著差异(P<0.01).服药期间肝肾功能无异常改变.[结论]羟苯磺酸钙是治疗糖尿病性皮肤溃疡有效安全的药物.  相似文献   
98.
Background: Three acid-reducing operations have recently been described for the laparoscopic treatment of peptic ulcer disease. These consist of a posterior truncal vagotomy combined with either (1) an anterior seromyotomy (SERO), (2) an anterior highly selective vagotomy (AHSV), or (3) a linear stapled lesser curvature excision (STAP). The purpose of this study was to investigate the physiologic effects of these procedures in terms of basal and maximal acid outputs. Methods: Fifty New Zealand rabbits were prospectively randomized into five open laparotomy groups (n= 10): a control group without vagal manipulation (CON), a bilateral truncal vagotomy with pyloromyotomy group (VP), a SERO group, an AHSV group, and a STAP group. All animals underwent placement of a gastrostomy tube for subsequent gastric secretory analysis. On postoperative day 6, basal acid outputs (BAO) and maximal acid outputs (MAO) following IV pentagastrin stimulation (30 μg/kg/h) were measured. Results were compared statistically using the ANOVA method. Results: Pentagastrin stimulation was associated with a significant increase in MAO in the CON group (p < 0.05 vs BAO); however, this response was effectively blunted in all the experimental groups. There were no differences in BAO or MAO between any of the vagotomized groups (SERO, HSV, STAP, VP). Conclusions: We conclude that the three acid-reducing procedures modified for laparoscopy are equally efficacious in reducing gastric acid secretion and that they compare favorably with VP. To our knowledge, this is the first report comparing basal and stimulated gastric acid secretion between these new acid-reducing techniques. Received: 27 March 1996/Accepted: 17 July 1996  相似文献   
99.
100.
荆芥连翘汤对促进皮肤溃疡愈合的影响   总被引:4,自引:0,他引:4  
目的 观察荆芥连翘汤对小鼠皮肤溃疡的治疗作用。方法 建立小鼠皮肤创伤和烫伤两种皮肤溃疡模型.比较荆芥连翘汤以及rhEGF的用药组和自身对照组小鼠皮肤溃疡面积,用昆微镜观察溃疡面炎症细胞浸润情况。结果 和自身对照组相比,荆芥连翘汤可明显缩小小鼠皮肤溃疡面积(P〈0.001),同时炎症细胞浸润显著减少(P〈0.001);荆芥连翘汤用药组疗效显著优于rhEGF用药组。结论 荆芥连翘汤可明显促进小鼠皮肤溃疡的愈合。  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