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   20694篇
  免费   1465篇
  国内免费   841篇
耳鼻咽喉   914篇
儿科学   400篇
妇产科学   489篇
基础医学   729篇
口腔科学   1113篇
临床医学   1765篇
内科学   1760篇
皮肤病学   168篇
神经病学   409篇
特种医学   551篇
外国民族医学   15篇
外科学   8020篇
综合类   3255篇
现状与发展   2篇
预防医学   750篇
眼科学   608篇
药学   672篇
  37篇
中国医学   144篇
肿瘤学   1199篇
  2024年   56篇
  2023年   485篇
  2022年   697篇
  2021年   871篇
  2020年   982篇
  2019年   880篇
  2018年   843篇
  2017年   755篇
  2016年   749篇
  2015年   679篇
  2014年   1364篇
  2013年   1260篇
  2012年   1126篇
  2011年   1453篇
  2010年   1276篇
  2009年   1155篇
  2008年   1123篇
  2007年   1131篇
  2006年   1010篇
  2005年   950篇
  2004年   706篇
  2003年   634篇
  2002年   581篇
  2001年   405篇
  2000年   262篇
  1999年   214篇
  1998年   190篇
  1997年   179篇
  1996年   145篇
  1995年   126篇
  1994年   94篇
  1993年   72篇
  1992年   76篇
  1991年   59篇
  1990年   40篇
  1989年   43篇
  1988年   47篇
  1987年   37篇
  1986年   26篇
  1985年   45篇
  1984年   36篇
  1983年   22篇
  1982年   41篇
  1981年   23篇
  1980年   14篇
  1979年   10篇
  1978年   5篇
  1977年   9篇
  1976年   5篇
  1973年   4篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
62.
Background: Gastro-gastric fistulas and marginal ulcers are frequent and serious complications of gastric compartmentalization procedures for obesity. Methods: The authors analyzed 810 patients after 911 operations for gastro-gastric fistulas and marginal ulcers over an 8-year period. All patients underwent a form of gastric bypass, in which a pouch is constructed along the lesser curvature of the stomach. The outlet of the pouch was restricted with a prosthetic band. In the first 189 patients (Group I), the pouch and stomach were stapled in continuity or partially divided. In the next 222 patients (Group II), segments were stapled and separated by transection. In the remaining 492 cases (Group III), in addition to transection of the stomach, a limb of jejunum was interposed between the pouch and excluded stomach. Stapled anastomoses were done in Group I and II patients and a portion of Group III patients. The remaining patients underwent hand-sewn anastomosis. Results: Gastro-gastric fistulas occurred in 49% of the patients in Group I, 2.6% of those in Group II, and 0% of those in Group III. In stapled anastomosis, the incidence of marginal ulceration in Groups I, II, and III were 8.5%, 5.4%, and 5.1%, respectively. In a subset of Group III patients, in whom a two-layer, hand-sewn anastomosis was done, the incidence was 1.6% when the outer layer was not absorbable and 0% when both layers were absorbable. Conclusions: Gastro-gastric fistulas and marginal ulcerations are likely the result of breakdown of the mucosa resulting from migrating staples and other foreign material. Lack of integrity of the gastric lining facilitates the action of the gastric digestive process. Transection of gastric segments with interposition of jejunum prevents gastro-gastric fistula formation. An intact serosa appears to block the digestion of bowel wall by gastric enzymes. Our early data suggest that the use of absorbable sutures at the gastrojejunostomy significantly decreases the incidence of marginal ulceration.  相似文献   
63.
64.
The surgical oncologist is sometimes confronted with a patient who was surgically treated for cancer of the thyroid gland and now has recurrent disease. In most instances, additional surgical treatment is indicated. The magnitude of surgery is primarily determined by the amount of tissue removed at the original operation. Surgery for recurrent disease may include completion of total thyroidectomy with dissection of lymphatic tissues in the thyroid compartment or/and neck dissection, preferably modified. Several clinical situations are outlined and discussed.  相似文献   
65.
刘健  洪流  孙业忠 《贵州医药》2003,27(7):608-610
目的 探索氩氮靶向冷冻治疗系统(氩氮刀)在脑胶质瘤治疗中的应用价值。方法 开颅后,根据MRI及CT设计冷冻范围,应用氩氮刀冷冻-复温-冷冻后切除胶质瘤,并取冷冻前后标本送病理检查。结果 8例Ⅱ~Ⅳ级胶质瘤患者肿瘤均达到全切,术中出血少,术后短期未见副作用及神经功能缺失。冷冻前后病理切片对比:与冷冻前对比,冷冻后标本在普通显微镜下见有明显出血灶;透射电镜下可见几乎所有细胞核膜肿胀,核形状不规则,染色质凝结为粗颗粒状,明显边聚,线粒体明显肿胀,部分破裂崩解。结论氩氮靶向冷冻治疗系统治疗脑胶质瘤具有能直接摧毁肿胀细胞、手术安全、出血少、全切率高的优点。  相似文献   
66.
经鼻内镜手术治疗鼻部脑膜脑膨出   总被引:1,自引:0,他引:1  
目的 探讨经鼻内镜手术治疗鼻部脑膜脑膨出的可行性并确立临床处理的基本原则。方法 经鼻内镜下采用剪除、电切、切割等方式切除鼻内型脑膜脑膨出 5例 ,并根据颅底缺损的不同情况选择使用肌肉、筋膜、软骨、骨等一期修补颅底。结果  5例均一次手术治愈 ,除 1例术后颅内感染 (脑膜炎 )外 ,无并发症发生 ,随访 1~ 5年无复发。结论 位于鼻腔内的脑膜脑膨出可以经鼻内镜手术完成 ,直径 0 5cm以下的颅底缺损可使用肌肉填塞和筋膜覆盖的方法修补 ,直径超过 0 5cm的颅底缺损应先使用软骨或骨封闭缺损 ,然后再用肌肉填塞和筋膜覆盖 ,以免复发。  相似文献   
67.
心外管道全腔肺动脉吻合术的临床应用   总被引:8,自引:1,他引:7  
Wu Q  Chu J  Zhu J  Liu P  Zhang H 《中华外科杂志》2000,38(11):847-849
目的 评价心外管道全腔肺动脉吻合术的临床应用价值。方法 1998年6月~1999年8月,10例先天性心脏复杂畸形的患者接受了心外管道全腔肺动脉吻合术。包括单心室8例,均伴有完全性大动脉转位;右心室发育不良2例。均在全麻低温体外循环下手术。结果 患者全部治愈出院。术后随访6~18个月,无晚期死亡。所有患者症状消失,无静脉压明显升高现象,超声检查显示心外管道血流通畅,无血栓形成;心电图检查显示无严重心  相似文献   
68.
Objective.The aim of this study was to define the clinical–therapeutical approach to endometrial cancer now being followed in some of the most important centers of reference for gynecological cancer in North America by means of a questionnaire.Study design.The questionnaire focused on four principal areas: (1) surgical staging and therapy; (2) adjuvant treatment; (3) treatment modifications; and (4) management of advanced stages (FIGO III–IV).Results.There were 48 evaluable responses (77%) received by the end of December 1994 which were considered for this analysis. Lymphadenectomy is utilized routinely in 26/48 centers (54.2%) and in selective clinical–pathological conditions in another 21/48 centers (43.5%). In the majority of centers (31/48; 64.6%) radical surgery is utilized for selected indications such as cervical involvement. Only 3/48 (6.2%) centers consider the vaginal approach totally inappropriate. The great majority (40/48; 83.3%) of the centers considered postsurgical adjuvant therapy to be necessary in FIGO Stage Ic. Brachytherapy is routinely performed in 3 centers (6.2%) in postsurgical management of Stage I endometrial cancer, while the majority of the centers (31/48; 64.6%) perform brachytherapy of the vaginal vault in certain clinical–pathological conditions. A wide variety of treatments are used for advanced stages (FIGO III–IV).Conclusions.It emerges that some controversial aspects exist on endometrial cancer treatment, and these conflicting data need a large-scale multicenter randomized clinical trial.  相似文献   
69.
Objective: To present the preliminary results of a new surgical procedure for posterior laryngeal cleft repair. Design: Retrospective study in an academic tertiary care center. Method: The study included three male patients (age at surgery, 2, 13, and 14 mo). One presented with severe aspiration and cyanotic attacks, the two others with aspiration and recurrent chest infections. The types of laryngeal clefts included complete cleft of the cricoid with varying degrees of tracheal involvement but not further than the first six tracheal rings. Associated malformations included one VATER syndrome, one esophageal atresia, and one tracheoesophageal fistula. Surgery was performed under general anesthesia with nasotracheaI intubation. A vertical anterior laryngofissure was performed. The mucosal margins of the clefts were incised and then repaired in two layers with polyglactin sutures. The original feature of this procedure was the interposition of a small piece of tibial periosteum between the two layers. This fascia graft is known to be strong and resistant in cleft palate surgery. Main Outcome Measure: Clinical and endoscopic follow-up was used for evaluation of results. Results: The three patients had successful laryngeal repair at a mean follow-up of 6 months (range, 4-14 mo). Conclusion: The anterior laryngofissure provides a good surgical access to the cleft. The interposition of tibial periosteum allows durability of the cleft repair. A longer follow-up is needed to confirm these preliminary results. A computed tomography scan study and a study on the rabbit are planned in order to evaluate the outcome of these periosteal grafts.  相似文献   
70.
Background. In Japan, much attention has recently been paid to super-extended paraaortic lymphadenectomy (PAL) for the treatment of advanced gastric cancer. However, it has been reported that PAL is associated with increased morbidity and mortality, as compared to conventional extended lymphadenectomy (D2 or D3). Therefore, an analysis of the effects of PAL on perioperative changes in the biological responses of patients essential for determining the potential utility of this procedure. Methods. The current non-randomized prospective study included evaluations of perioperative changes in parameters of surgical stress (series I; serum levels of antidiuretic hormone, interleukin-6, trypsin, and phospholipase A 2 ) and immunocompetence (series II; phytohemagglutinin- and concanavalin A-induced blastogenesis, activity of natural killer cells and the ratio of CD4 cells to CD8 cells) in patients with advanced gastric cancer (T3 or T4), comparing groups treated with D3 plus PAL ( n = 12) and D3 ( n = 13), and a control group with early gastric cancer ( n = 16) treated with D1 lymphadenectomy (perigastric N1 nodes) between April 1995 and April 1997. Results. The duration of surgery and the amount of blood lost were longer and greater in the D3 plus PAL group than in the D3 and D1 groups. D3 plus PAL and D3 were associated with significant postoperative increases in parameters of surgical stress, as well as with significant postoperative immunosuppression, compared to results with D1. However, there were no significant differences in the respective parameters between the D3 plus PAL and D3 groups. Conclusions. Our results indicate that there are no essential differences in patients' biological responses between D3 plus PAL and D3 lymphadenectomy. It appears that PAL-associated morbidity can be minimized by very careful manipulation during the dissection of paraaortic lymph nodes. Received for publication on Feb. 10, 1998; accepted on Jun. 3, 1998  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