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   78270篇
  免费   5270篇
  国内免费   1665篇
耳鼻咽喉   3117篇
儿科学   970篇
妇产科学   1541篇
基础医学   2048篇
口腔科学   3147篇
临床医学   7302篇
内科学   7944篇
皮肤病学   706篇
神经病学   2633篇
特种医学   1272篇
外国民族医学   20篇
外科学   26616篇
综合类   10500篇
现状与发展   6篇
一般理论   3篇
预防医学   2929篇
眼科学   4654篇
药学   3173篇
  167篇
中国医学   853篇
肿瘤学   5604篇
  2024年   261篇
  2023年   2097篇
  2022年   3220篇
  2021年   4224篇
  2020年   4174篇
  2019年   3581篇
  2018年   3438篇
  2017年   2955篇
  2016年   2945篇
  2015年   2992篇
  2014年   5915篇
  2013年   5570篇
  2012年   4430篇
  2011年   4666篇
  2010年   3701篇
  2009年   3515篇
  2008年   3374篇
  2007年   3353篇
  2006年   2951篇
  2005年   2589篇
  2004年   2222篇
  2003年   1796篇
  2002年   1429篇
  2001年   1363篇
  2000年   1179篇
  1999年   1074篇
  1998年   886篇
  1997年   840篇
  1996年   632篇
  1995年   510篇
  1994年   452篇
  1993年   362篇
  1992年   306篇
  1991年   301篇
  1990年   208篇
  1989年   198篇
  1988年   199篇
  1987年   200篇
  1986年   157篇
  1985年   179篇
  1984年   171篇
  1983年   111篇
  1982年   119篇
  1981年   105篇
  1980年   79篇
  1979年   46篇
  1978年   34篇
  1977年   34篇
  1976年   25篇
  1975年   20篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
91.
OBJECTIVE The present study was designed to develop the "ThreeGrade Criteria" for radical resection of primary liver cancer (PLC) and to evaluate its clinical significance.METHODS Criteria for radical resection of PLC were summed up to 3 grades based on criterion development. Grade I: complete removal of all gross tumors with no residual tumor at the excision margin. Grade Ⅱ: on or the primary branches of the portal vein, the common hepatic duct or its dition to the above criteria, negative postoperative follow-up result including AFP dropping to a normal level (with positive AFP before surgery)within 2 months after operation, and no residual tumor upon diagnostic imaging.The clinical data from 354 patients with PLC who underwent hepatectomy were reviewed retrospectively. Based on the "Three-Grade Criteria" these patients were divided into 6 groups: Grade Ⅰ radical group,Grade Ⅰ palliative group, Grade Ⅱ radical group, Grade Ⅱ palliative group,Grade Ⅲ radical group, Grade Ⅲ palliative group. The survival rate of each group was calculated by the life-table method and the rates compared among the groups.RESULTS The survival rate of patients receiving radical treatment was better than those receiving palliative treatment (P<0.01). Survival improved as more criteria were applied. The 5-year survival rate of the patients in Grade Ⅰ, Ⅱ and Ⅲ who underwent radical resection was 43.2%,51.2% and 64.4%, respectively (P<0.01).CONCLUSION The "Three-Grade Criteria" may be applied for judging the curability of resection therapy for PLC. The stricter the criterion used,the better the survival would be. Adopting high-grade criteria to select cases and guide operations and strengthening postoperative follow-up would improve the results of hepatectomy for PLC.  相似文献   
92.
目的 探讨Ⅴ型斜视伴原发性下斜肌功能过强的治疗效果。方法根据手术方式将49例Ⅴ型斜视伴下斜肌功能过强惠者分为四组,分别采用水平肌加强减弱术不联合下斜肌切断减弱术(Ⅰ组)、联合单侧下斜肌切断减弱术(Ⅱ组)、联合双侧下斜肌对等切断减弱术(Ⅲ组)及联合双侧下斜肌不对等切断并部分切除减弱术(Ⅳ组)治疗Ⅴ型斜视。结果Ⅴ型斜视伴原发性下斜肌功能过强采用四种方式治疗后,眼位正位,下斜肌功能亢进改善+~++,双侧下斜肌功能对等,术前术后原在位度数和上下注视25。斜视角之差的差异有非常显著性(P〈0.001)。结论根据单侧或双侧下斜肌功能过强的具体情况来选择不同的手术方式治疗Ⅴ型斜视伴原发性下斜肌功能过强,眼位矫正满意,同时手术方式简单、安全有效。  相似文献   
93.
Gastrogastric fistula: a possible complication of Roux-en-Y gastric bypass.   总被引:4,自引:0,他引:4  
BACKGROUND: Gastrogastric fistula is a communication between the proximal gastric pouch and the distal gastric remnant, rarely described in the realm of bariatric procedures. The aim of this study was to review the existing literature about this topic and to demonstrate its laparoscopic treatment. METHODS: An extensive literature review found several articles reporting this complication. However, no citation was found describing the steps of the laparoscopic management of this situation. RESULTS: Gastrogastric fistula occurs in up to 6% of Roux-en-Y gastric bypasses. Two theories exist for fistula formation: (1) it is a technical complication derived from the incomplete division of the stomach during the creation of the pouch, and (2) it occurs after a staple-line failure, developing a leak with an abscess, which then drains into the distal stomach forming the fistula. Early symptoms include fever, tachycardia, and abdominal pain. Failure in weight loss is a late clinical sign observed in these patients. Diagnosis is based on radiologic study, upper endoscopy and computed tomography. When identified in the acute postoperative course, laparoscopic treatment is easy. Chronic fistulas are difficult to manage, and the laparoscopic approach is an alternative to open surgery. CONCLUSIONS: Gastrogastric fistula is a possible complication of Roux-en-Y gastric bypass and its laparoscopic treatment is feasible.  相似文献   
94.
95.
目的 探讨内镜辅助肋骨-软骨移植重建髁突与同期正颌手术治疗严重颞下颌关节病变及牙颌面畸形的效果. 方法 于术前对患者进行临床检查和治疗设计,术中行Le Fort Ⅰ型截骨术、下颌支矢状骨劈开术、髁突等关节区病变的处理、内镜辅助下肋骨-软骨移植和颏成形术,术后进行随访. 结果 2003年9月至2005年12月,于临床应用15例,所有患者同期手术均顺利完成.术中、术后均无严重出血、神经损伤、受区感染等严重并发症发生.术后随访29~52个月,平均31.8个月,所有患者面容均显著改善,关节功能良好,且无关节区疼痛等主观症状,患者对手术疗效满意.术后张口度平均为33.6 mm,侧向运动度为0~6 mm. 结论 选择合适的适应证、设计合理的手术方案,内镜辅助髁突重建同期正颌手术效果较好.  相似文献   
96.
随着整形美容外科专业在我国的蓬勃发展,国内不同等级的医疗机构对经过正规培训的整形美容外科医生的需求逐年在增加。为了提高教学效果,针对整形外科不同层次的学生,我们采用了多种形式、有针对性的教学模式,并取得了一定的效果。本文分别从教学查房、手术带教、读书报告、技能培训、学术交流、专题讲座等多个层面浅析了整形外科临床教学模式。  相似文献   
97.
BACKGROUND AND OBJECTIVES: Feasibility of ambulatory laparoscopic inguinal hernia repair in developing countries is not known due to lack of dedicated outpatient centers. This study prospectively evaluated the feasibility of outpatient discharge after laparoscopic total extraperitoneal inguinal hernia repair done in combination with in-hospital services and its impact on quality of life. METHODS: Forty patients were studied who had uncomplicated inguinal hernias and fulfilled the selection criteria. Quality of life was evaluated by using the SF-12 questionnaire. RESULTS: Ninety percent of patients could be discharged as outpatients. Four patients required admission. No major complications or readmissions occurred. Physical components of quality of life deteriorated in the immediate postoperative period but improved to above preoperative levels within one month. A transient deterioration in subgroups of the mental health component was observed, which recovered to normal in less than a week. There was no significant alteration in the emotional component. There has been no recurrence at a median follow-up of 25 months. CONCLUSION: It was feasible to safely perform outpatient TEP in combination with routine in-hospital services without increasing complications or causing any adverse impact on quality of life. This was possible subject to adherence to proper selection and discharge criteria.  相似文献   
98.
Small bowel transplantation (SBT) is associated with poorly understood enteric dysfunction. The study of SBT in mice is hindered by the technical difficulty of orthotopic SBT in the mouse. Our aim was to develop an easy preparation of extrinsic denervation of the entire jejunoileum in mice as a model of orthotopic SBT. All neurolymphatic tissues accompanying the superior mesenteric artery (SMA) and vein (SMV) were ligated just distal to the middle colic vessels. The SMA and SMV were then stripped of investing adventitia, and the mesentery to jejunum and colon were transected radially. Jejunum and colon were not transected and reanastomosed. To confirm extrinsic denervation 1, 3, and 6 months later, segments of small bowel were stained for protein gene product 9.5 (PGP9.5) and tyrosine hydroxylase (TH). Tyrosine hydroxylase immunoreactive intensity was then quantified using a semiquantitative analysis. Immunohistochemical fluorescence showed persistence of PGP9.5 immunoreactivity confirming enteric nerves in jejunoileum; however, there was no TH immunoreactivity in jejunoileum in denervated mice despite the expected preservation of TH immunoreactivity in the still-innervated duodenum at 1 month. At 3 months, sparse immunoreactivity for TH was present, and by 6 months, reinnervation of TH-containing nerves appeared similar to controls. Quantification of intensity at each time-point further confirmed this trend. This technique in the mouse accomplishes a complete extrinsic denervation of jejunoileum early postoperatively (1 and 3 months); reinnervation occurs by 6 months. This is an easily learned murine model of orthotopic SBT. Presented at the American Gastroenterological Association during Digestive Disease Week in Los Angeles, CA, as a poster presentation on May 23 2006. Abstract published in GastroenterologyE 2006; 130:A604.  相似文献   
99.
Laparoscopic pancreatic surgery (LPS) has seen significant development but much of the knowledge refers to small and benign pancreatic tumors. This study aims to evaluate the feasibility, safety, and long-term outcome of the laparoscopic approach in patients with benign, premalignant, and overt malignant lesions of the pancreas. This study, currently, is the largest single center experience worldwide. One hundred twenty-three consecutive patients underwent laparoscopic pancreatic surgery from April 1998 to April 2007, 20 patients with cysts or pseudocysts for acute and chronic pancreatitis, laparoscopic pancreatic drainage was performed, and were excluded from the analysis. The 103 patients were divided based on preoperative diagnosis: group I, inflammatory tumors for chronic pancreatitis (eight patients); group II, cystic pancreatic neoplasms (29 patients); group III, intraductal papillary mucinous neoplasms (10 patients); group IV, neuroendocrine pancreatic tumors (NETs) (43 patients); and group V ductal adenocarcinoma (13 patients). The median tumor size was 5.3 cm. Pathologic data include R 0 or R 1 resection (transection margins on the specimen were inked). Perioperative data, postoperative complications, and resection modalities were compared using statistical analysis. Long-term outcomes were analysed by tumor recurrence and patient survival. The overall conversion rate was 7%. Laparoscopic distal pancreatic resection was performed in 82 patients (79.6%). Laparoscopic spleen-preserving distal pancreatectomy (Lap SPDP) was performed in 52 patients (63.7%), but with splenic vessels preservation in 22% and without splenic vessels preservation in 41.5%. Laparoscopic en-bloc splenopancreatectomy (Lap SxDP) was performed in 30 patients (36.6%) and laparoscopic enucleation (Lap En) in 20 patients (19.4%). There was no mortality. The overall complication rate was 25.2, 16.7, and 40% after Lap SPDP, Lap SxDP, and Lap En, respectively. The overall morbidity rate was significantly higher (p > 0.05) in the group of Lap SPDP without splenic vessels preservation comparing with Lap SPDP with splenic vessels preservation because of the occurrence of splenic complications (20.6%). The overall pancreatic fistulas was 7.7, 10, and 35% after Lap SPDP, Lap SxDP, and Lap En, respectively; the severity of fistula was significantly higher in the Lap En group (p > 0.05). The mean hospital stay was within 1 week in all groups, except in the group of ductal adenocarcinoma, which is 8 days. In this series, 27 patients (26.2%) had malignant disease. R 0 resection was achieved in 90% of ductal adenocarcinoma and 100% for other malignant tumors. The median survival for ductal adenocarcinoma patients was 14 months. This series demonstrates that LPS is feasible and safe in benign-appearing and malignant lesions of the pancreas.  相似文献   
100.
Background The incidence rate of incisional hernias after open surgery has been reported to be higher than that of port site hernias after laparoscopic surgery. No studies have compared the costs for the health care system in treating those two types of hernia. Methods A systematic review was conducted to obtain the baseline data, and a decision analysis model was created to simulate the occurrence and recurrence of incisional and port site hernias. Results The overall risk of having incisional hernias was eight-times higher than that of having port site hernias (7.4% vs 0.9%). A cost savings of £93 per patient can be generated for the health care system in the UK. Similar results were obtained for Germany, Italy and France. Conclusions The additional treatment costs for incisional hernia should be taken into account when the costs of a surgery performed by open approach are compared with by laparoscopy.  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