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   9708篇
  免费   1123篇
  国内免费   368篇
耳鼻咽喉   787篇
儿科学   68篇
妇产科学   57篇
基础医学   296篇
口腔科学   34篇
临床医学   1334篇
内科学   4462篇
皮肤病学   6篇
神经病学   140篇
特种医学   167篇
外科学   1882篇
综合类   993篇
预防医学   175篇
眼科学   121篇
药学   261篇
  11篇
中国医学   56篇
肿瘤学   349篇
  2024年   34篇
  2023年   309篇
  2022年   458篇
  2021年   554篇
  2020年   590篇
  2019年   523篇
  2018年   544篇
  2017年   455篇
  2016年   540篇
  2015年   455篇
  2014年   778篇
  2013年   772篇
  2012年   496篇
  2011年   607篇
  2010年   489篇
  2009年   470篇
  2008年   430篇
  2007年   408篇
  2006年   346篇
  2005年   299篇
  2004年   298篇
  2003年   210篇
  2002年   189篇
  2001年   134篇
  2000年   120篇
  1999年   87篇
  1998年   99篇
  1997年   79篇
  1996年   57篇
  1995年   68篇
  1994年   61篇
  1993年   47篇
  1992年   39篇
  1991年   39篇
  1990年   39篇
  1989年   18篇
  1988年   12篇
  1987年   10篇
  1986年   7篇
  1985年   7篇
  1984年   4篇
  1983年   5篇
  1982年   4篇
  1981年   2篇
  1980年   4篇
  1978年   1篇
  1977年   1篇
  1975年   1篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
31.
The results of a postal questionnaire indicate an exponential rise in the practice of functional endoscopic sinus surgery (FESS) in the UK and a major complication rate of 0.23%. Cerebrospinal fluid leak was the most common serious complication accounting for 24 of the 36 reports.  相似文献   
32.
直视下经尿道内切开术治疗尿道狭窄   总被引:6,自引:0,他引:6  
目的:探讨直视下经尿道内次切开术治疗尿道狭窄的有效性和安全性。方法:总结直视下经尿道内切开术治疗68例尿道狭窄和闭锁患者的疗效和经验,63例1次手术成功;3例行2次、2例行3次成功。结果:68例中,57例术后随访3~71个月,平均28.3个月,43例(75%)均排尿通畅;2例暂时性尿失禁者分别于术后3~6月内恢复。结论:直视下经尿道内切开术创伤小,并发症少,疗效确切,是尿道狭窄和闭锁的首选治疗方法。  相似文献   
33.
A wireless power transfer system for endoscopic micro-robot operating at 36 kHz is presented in this paper. The issue of patient' s health and safety regarding exposure to the electromagnetic field is addressed. The specific absorption rate and current density can be used to investigate the electromagnetic influences on the biological tissues surrounded by the wireless power launching coil. In view of this purpose, the limited close-ound solenoid electromagnetic model is built, the relationship between the electric intensity and the specific absorption rate and current density is deduced, and the simulation experiments are done. Experimental results show that the values of SAR and current density related to different tissue catalogs are all very small and do not exceed their own limits respectively when the resonance frequency of operation is 36 kHz.  相似文献   
34.
目的:探讨应用针形内窥镜对小儿鼻颅底疾病进行探查与手术的方法及疗效。方法:在外径1.9mm的进口针形内窥镜及电视同图像系统监视下,对8例小儿(7d ̄12岁)鼻颅底有关疾病进行探杳与手术。结果:先天性后鼻孔闭锁3例中,1例好转,3例痊愈。外伤性脑脊液鼻漏1例,经修补痊愈先天性脑膜脑膨出2例,确诊后1例暂缓治疗。另1例行内窥镜手术痊愈。颅底神经母细胞瘤2例取材作病理检查确诊。结论:在电视图像监视下应用  相似文献   
35.
Percutaneous endoscopic gastrostomy in burn patients   总被引:2,自引:0,他引:2  
Background: Prolonged enteral feedings are required occasionally in seriously burned individuals. We have employed percutaneous endoscopic gastrostomy (PEG) in selected patients who require particularly prolonged access, thus prompting this review. Methods: The PEG procedure was performed under general anesthesia in combination with another surgical procedure using a variety of commercially available needle and guidewire kits in 14 patients. Results: These 14 patients had an average age of 55.2 ± 6.6 years and a burn involving 38 ± 8% of the body surface. Eleven of these patients had suffered an inhalation injury. The tubes were placed an average of 57 ± 10.5 days after injury through unburned and unharvested skin in four patients (28%), healed donor sites in five patients (35%), healed burn in one patient (1%), and grafted burn in four patients (28%). One patient, whose catheter was placed through a grafted fascial excision, developed moderate local wound erosion. Tubes were known to have been left in place as long as 155 days. However, most were removed in rehabilitation hospitals, and we were unable to determine how long most were left in place. We are unaware of any problems with the tubes occurring after discharge from the acute care setting. Conclusions: In selected patients, PEG can provide more comfortable access for prolonged enteral feedings than nasogastric tubes and can be placed with minimal morbidity. Received: 29 March 1998/Accepted: 1 August 1998  相似文献   
36.
This case study reports the progress of a 41-year-old man with advanced Huntington's disease (HD) during a 12-week period when he was fed a high-energy regimen via percutaneous endoscopic gastrostomy (PEG). The regimen consisted of a low-protein, low-mineral, energy-dense (2 kcal mL?1) carbohydrate polymer. Achieving weight gain with a 1.5 kcal mL?1 feed and carbohydrate polymer had produced steady but slow results (52–56 kg – a rise of 4 kg in 15 months). It was concluded that a more energy-dense regimen would facilitate faster weight gain.  相似文献   
37.
目的 回顾分析鼻内镜手术治疗慢性鼻窦炎鼻息肉的疗效及影响因素.方法 总结132例(196侧)慢性鼻窦炎鼻息肉患者的临床资料.结果 全组均随访3~12个月,治愈率72.7%,好转率21.2%,总有效率93.9%.无效6.1%.结论 鼻内镜手术治疗鼻窦炎鼻息肉刨伤小、疗效好,熟练精细的手术操作和正确的术后治疗是提高治愈率的关键.  相似文献   
38.
BackgroundEsophageal stricture is a major complication of endoscopic submucosal dissection (ESD) in patients with superficial esophageal cancer (SEC). Oral steroids have been used to prevent esophageal stricture in patients with more than 75% of the esophageal circumference resected. However, there are no established guidelines regarding the optimal duration of steroid use. This retrospective observational study aimed to compare the incidence of esophageal stricture according to the period of prophylactic oral steroid use and to identify the risk factors for esophageal stricture.MethodsEighty-one patients who were prescribed prophylactic steroid after undergoing ESD for SEC with more than 75% of esophageal circumference resected were enrolled. Patients were classified into the four-week steroid group (n=72) or eight-week steroid group (n=9) to compare the incidence of esophageal stricture. In addition, the patients were subdivided into those who developed esophageal stricture (n=24) and those who did not (n=57) to identify the risk factors for esophageal stricture.ResultsTwenty patients (27.8%) in the four-week oral steroid group and four patients (44.4%) in the eight-week oral steroid group developed esophageal stricture (P=0.44). The univariable analysis identified tumor size, longitudinal length of semi-circumferential resection, and proportion of circumferential resection as risk factors of esophageal stricture. The multivariable analysis identified the proportion of circumferential resection as an independent risk factor. After adjusting for the proportion of circumferential resection, the incidence of stricture was marginally higher in the eight-week steroid group [P=0.05; odds ratio (OR): 5.69; 95% confidence interval (CI): 1.01–32.15].ConclusionsEight weeks of oral steroid prophylaxis does not reduce the risk of stricture after extensive ESD more than four weeks of oral steroid prophylaxis. The proportion of circumferential resection is the strongest risk factor for stricture in patients with SEC undergoing ESD.  相似文献   
39.
目的 探讨经内窥镜切开十二指肠乳头括约肌治疗胆总管结石的成功因素及安全性.方法 将2005年1月-2010年1月间,实施内窥镜下十二指肠乳头切开(EST)治疗胆总管结石的135例分为两组:2005年1月-2007年12月为第一组(60例),2008年1月-2010年1月为第二组(75例),对其手术成功率、并发症发生率进行比较.结果 第一组成功48例,其中一次性取出44例,分次取出4例,成功率80.0%,失败12例,并发症发生率16.7%(10/60).第二组成功72例,其中一次性取出69例,分次取出3例,成功率96.0%,失败3例,并发症发生率6.7%(5/75).结论 经内镜切开十二指肠乳头括约肌治疗胆总管结石是一种安全性高的微创手术,熟练的内镜操作技术和规范诊疗途径可以提高手术成功率,降低并发症发生率.  相似文献   
40.
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