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   9352篇
  免费   1131篇
  国内免费   312篇
耳鼻咽喉   784篇
儿科学   67篇
妇产科学   56篇
基础医学   307篇
口腔科学   34篇
临床医学   1286篇
内科学   4207篇
皮肤病学   6篇
神经病学   155篇
特种医学   163篇
外科学   1846篇
综合类   972篇
预防医学   158篇
眼科学   119篇
药学   248篇
  9篇
中国医学   52篇
肿瘤学   326篇
  2024年   21篇
  2023年   309篇
  2022年   344篇
  2021年   551篇
  2020年   588篇
  2019年   529篇
  2018年   555篇
  2017年   465篇
  2016年   543篇
  2015年   454篇
  2014年   769篇
  2013年   755篇
  2012年   481篇
  2011年   599篇
  2010年   467篇
  2009年   454篇
  2008年   410篇
  2007年   380篇
  2006年   328篇
  2005年   276篇
  2004年   278篇
  2003年   194篇
  2002年   175篇
  2001年   123篇
  2000年   113篇
  1999年   82篇
  1998年   93篇
  1997年   73篇
  1996年   52篇
  1995年   60篇
  1994年   57篇
  1993年   43篇
  1992年   36篇
  1991年   38篇
  1990年   36篇
  1989年   17篇
  1988年   11篇
  1987年   8篇
  1986年   6篇
  1985年   5篇
  1984年   2篇
  1983年   5篇
  1982年   3篇
  1981年   1篇
  1980年   3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 19 毫秒
41.
The Otomize (Stafford-Miller Ltd) aerosol spray is a new device for delivering topical ear medication in otitis externa. Both the manufacturers and a recent study have claimed that the spray produces better coverage of the external ear canal than do traditional ear-drops. We performed an endoscopic photographic comparison study to investigate this claim. The area of tympanic membrane and ear canal covered with medication was greater in those ears treated with the aerosol (P < 0.001, paired t-test). The ability of the aerosol to deliver drug to the level of the tympanic membrane suggests a possible role for this device in the treatment of chronic otitis media. The technique of endoscopic photography provides an objective and reproducible means of investigating drug delivery systems for otological conditions.  相似文献   
42.
肝门部恶性肿瘤手术切除率极低,临床处理十分棘手。作者采用内镜胆管引流术治疗此类肿瘤288例次(肝门部胆管癌184例、胆囊癌23例、肝细胞癌侵犯肝门部胆管47例、其他转移性肿瘤34例),其中行内镜鼻胆管引流162例次、塑料内置管引流80例次、放置可膨式金属胆道支架46例、4例患者接受同期双内置管引流。引流总有效率为67.0%,其中效果满意者43.1%;40例患者术后1个月内发生胆管炎,发生率为13.8%,3例死亡;长期随访病例的平均存活期5.3个月。我们观察到治疗的效果与Bismuth分型有密切关系,如果全肝40%以上的胆系得到引流,黄疸有望消退;左、右两侧胆管同时引流可扩大引流范围,提高疗效;应合理选择三种内镜胆管引流方法并适时灵活转换才能获得满意的疗效。结论:对于肝门部肿瘤,内镜胆管引流术是一种安全有效的治疗手段,可作为首选的姑息性治疗。  相似文献   
43.
44.
Technical improvements, such as mechanical lithotripsy, stenting or nasobiliary drainage, and wire-guided cannulation, have reduced the risk of complications in endoscopic sphincterotomy. To determine the extent of this reduction in risk, we assessed the medical records of 1352 patients with common bile duct stones in whom the procedure was conducted. Complications examined were: acute cholangitis and pancreatitis. Stone clearance was achieved in 1256 patients (92.8%), with an overall morbidity rate of 7.7% and a mortality rate of 0.15%. One hundred and forty-two patients had stones with a diameter greater than 20mm; 97 of these patients did not undergo lithotripsy. Cholangitis occurred in 10 of these 97 patients (10.3%), whereas, in the 45 patients who underwent lithotripsy, there were no cases of cholangitis (P=0.02). Stone removal was not immediately accomplished or attempted in 396 patients. In 82 of these patients in whom a stent or a nasobiliary drain was placed in the common bile duct, the incidence of cholangitis was 1.2%, significantly less (P=0.045) than the incidence of 6.4% in the other 314 patients given no stenting or nasobiliary drain. To overcome difficult cannulation, precut sphincterotomy was conducted in 134 patients and wireguided sphincterotomy, a recently introduced procedure, was conducted in 55 patients. When the precutting technique was used, the incidence of acute pancreatitis was significantly higher (8/134; 6.0%) than that in the patients in whom the standard procedure was conducted, i.e., neither the precut technique nor wire-guided ES was used (23/1218; 1.9%) (P=0.008). There were no cases of pancreatitis in the 55 patients in whom wire-guided sphincterotomy was performed, although the difference was not statistically significant because of the small number of patients (P=0.06). Based on these findings, we conclude that improved technologies have led to a significant reduction of complications in endoscopic sphincterotomy.  相似文献   
45.
回顾分析 65例脑脊液鼻漏病例。随访 3个月~ 1 0年 ,其中 2 6例经保守治疗痊愈 ,治愈率 40 %。 3 9例经保守治疗无效的患者 9例自动离院 ;行开颅手术修补 7例 ,其中 3例治愈 ;行鼻外入路修补术 3例 ,全部治愈 ;经鼻内镜修补术 2 0例 ,其中 1次手术治愈 1 9例 ,2次手术治愈 1例。经鼻内镜脑脊液鼻漏修补术的成功率为 1 0 0 % ,其中 1次修补成功率为 95 %。结果提示 :鼻内镜下脑脊液鼻漏修补术是外科治疗脑脊液鼻漏的首选术式  相似文献   
46.
A report of a patient with an azygos lobe and an associated anomalous azygos vein covering the upper thoracic sympathetic chain. This anomaly poses a significant risk during the procedure of endoscopic thoracic sympathectomy. A chest X-ray is useful in detecting this anomaly and alerting the surgeon to potential problems.  相似文献   
47.
舒越 《中国厂矿医学》2004,17(4):269-270
目的 介绍应用经皮内镜下胃造口术(PEG)实施肠内营养支持。方法 在内镜引导下行胃造口术.7例病人均予以肠内营养。结果 7例病人置管8次,成功率100%,6例经治疗后恢复情况好,无严重并发症。结论在肠内营养输注途径中PEG具有创伤小、时间短、经济,安全等特点。易于护理和长期使用。  相似文献   
48.
We investigated the relationship between esophageal varices and the collaterals by endoscopy and endoscopic ultrasound (20 MHz ultrasonic miniprobe; UMP). Moreover, we investigated the correlation between the collaterals around the esophagus and recurrence of esophageal varices in patients with portal hypertension who had undergone EIS. The collaterals were divided into two groups: peri‐esophageal collateral veins (peri‐ECVs) and para‐esophageal collateral veins (para‐ECVs). These were scored as mild or severe according to the stage of development. According to endoscopy, the varix form was significantly larger in severe the peri‐ECVs group than in mild the peri‐ECVs group. The prevalence of perforating veins increased according to the varix form. With regard to variceal recurrence, in patients with variceal recurrences, UMP findings included a significantly higher incidence of severe peri‐ECVs, a significantly larger diameter of perforating veins compared with patients without recurrence. In conclusion, the presence of severe peri‐ECVs and large perforating veins in the esophageal wall strongly correlates with occurrence and recurrence of esophageal varices in patients with portal hypertension. An understanding of these UMP abnormalities on the basis of hemodynamics around the esophagus is thought to be important for management of esophageal varices in patients with portal hypertension.  相似文献   
49.
Endoscopic ultrasound (EUS) is sensitive for staging gastrointestinal malignancies and pancreatic lesions. EUS‐fine‐needle aspiration (EUS‐FNA) offers a diagnostic accuracy of about 60–90% for pancreatic tumors and > 90% for lymph nodes. There are several limitations of EUS‐FNA including the need for on‐site cytopathology review. In addition, accuracy of cytologic review is hampered by the presence of blood, benign epithelial cells, desmoplasia, and well‐differentiated tumors. Furthermore, the small biopsy sample and destruction of tissue architecture limits the diagnostic sensitivity for GISTs and lymphomas. Many of these problems can be overcome with use of EUS trucut biopsy (TCB) needles. These large caliber, cutting needles acquire larger tissue samples allowing preservation of tissue architecture and histologic examination. Our recently described experience with EUS‐TCB initially in swine and later humans demonstrated the safety for acquiring histologic tissue representative of the target organs sampled enabling accurate diagnosis. These studies suggested greater diagnostic accuracy of EUS‐TCB for submucosal mass lesions and lymphoma and potentially the need for fewer needle passes for solid pancreatic neoplasms. In this paper we will review the current TCB literature, device design and technique, help troubleshoot potential problems, and offer opinion as to the utility and role of this new device.  相似文献   
50.
目的 探讨Oddi括约肌狭窄的诊断及治疗方法.方法 对1990年至2005年间45例Oddi括约肌狭窄的临床资料进行回顾性分析.结果 45例中有27例术前进行过磁共振胆胰管造影(MRCP)检查,8例获得诊断;25例切开十二指肠行括约肌成形术,术后病理证实为Oddi括约肌狭窄;20例经ERCP确诊,并行内镜括约肌切开术.因MRCP的广泛使用,2000年后Oddi括约肌狭窄的术前诊断率明显提高,2000年前为2/27,2000年后为6/18(χ2=4.79,P<0.05).内镜括约肌切开术术后胰腺炎发生率为3/20,经十二指肠Oddi括约肌成形术术后胰腺炎发生率为4/25(χ2=0.01,P>0.9).结论 MRCP是诊断Oddi括约肌狭窄理想的非损伤性检查;内镜括约肌切开术是治疗Oddi括约肌狭窄的有效方法.  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