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   88093篇
  免费   5730篇
  国内免费   2052篇
耳鼻咽喉   3205篇
儿科学   1106篇
妇产科学   1553篇
基础医学   2844篇
口腔科学   3286篇
临床医学   8447篇
内科学   7636篇
皮肤病学   709篇
神经病学   3478篇
特种医学   1976篇
外国民族医学   20篇
外科学   30038篇
综合类   12437篇
现状与发展   6篇
一般理论   2篇
预防医学   3015篇
眼科学   5009篇
药学   3504篇
  183篇
中国医学   1745篇
肿瘤学   5676篇
  2024年   314篇
  2023年   2296篇
  2022年   3553篇
  2021年   4644篇
  2020年   4606篇
  2019年   3835篇
  2018年   3687篇
  2017年   3284篇
  2016年   3358篇
  2015年   3346篇
  2014年   6739篇
  2013年   6212篇
  2012年   5114篇
  2011年   5345篇
  2010年   4184篇
  2009年   4037篇
  2008年   3801篇
  2007年   3843篇
  2006年   3329篇
  2005年   2934篇
  2004年   2522篇
  2003年   2094篇
  2002年   1660篇
  2001年   1553篇
  2000年   1362篇
  1999年   1205篇
  1998年   988篇
  1997年   948篇
  1996年   733篇
  1995年   586篇
  1994年   521篇
  1993年   409篇
  1992年   363篇
  1991年   335篇
  1990年   231篇
  1989年   229篇
  1988年   222篇
  1987年   217篇
  1986年   181篇
  1985年   206篇
  1984年   175篇
  1983年   114篇
  1982年   132篇
  1981年   108篇
  1980年   88篇
  1979年   61篇
  1978年   53篇
  1977年   45篇
  1976年   31篇
  1975年   22篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
Background: The bariatric patient exists in dynamic relationship with family members and friends who have considerable influence upon the patient and his or her surgical outcome. When family members and friends behave as intimate saboteurs, they attempt to hamper, hurt, or subvert the bariatric patient's goal of achieving and maintaining a healthy body weight. Successful or not, intimate saboteurs provide significant treatment challenges for the patient and the treatment team. Methods and Patients: Patient profiles provide examples of intimate sabotage. The psychological construct of Family Systems Theory is used as a plausible explanation for the sabotage of friends and family. Conclusions: Multidisciplinary professionals treating the bariatric patient must be aware of the critical influence of intimate saboteurs and the tactics they use to sabotage. Treatment guidelines recommended by Family Systems Theory are presented as strategies to mitigate the influence of intimate saboteurs.  相似文献   
22.
Acupuncture analgesia (AA) caused by low frequency stimulation of the acupuncture point (AP) was abolished by hypophysectomy and adrenalectomy. Termination of the AA producing pathway from the AP to the pituitary gland was in the medial hypothalamic arcuate nucleus (M-HARN). The origin of the descending pain inhibitory system associated with AA was in the posterior HARN (P-HARN). AA in the hypophysectomized rats, and enhanced neuronal activity in the P-HARN that were abolished during acupuncture stimulation, were both restored by intraperitoneal microinjection of 0.5 mg/kg morphine or 0.1 micrograms beta-endorphin into the P-HARN during acupuncture stimulation. Of the analgesia produced by dopamine or beta-endorphin injected into the P-HARN, that caused by beta-endorphin disappeared after denervation of the M-HARN. The P-HARN neurons that responded to acupuncture stimulation also responded to iontophoretic dopamine, but not to iontophoretic morphine nor ultramicroinjected beta-endorphin. The transmission between the M-HARN and P-HARN may be dopaminergic, and beta-endorphin might presynaptically modulate this transmission. Reduction of sodium ions may have been the reason for abolition of AA after adrenalectomy.  相似文献   
23.
目的探索以虚拟现实技术为基础的枢椎椎弓根螺钉置人方法。方法选取8具成人颅一颈椎标本,采用改良四柱式定位框架固定于枕颈,使颅-颈-肩形成统一刚体,保持空间位置恒定,CT薄层扫描获取枢椎三维定位信息,采用Aero—Tech立体定向手术规划系统三维建模,设计安全、可视化、个体化的虚拟置钉路径,反复虚拟演示验证钉道安全后,导向弓把持下置人导向钢针,复查CT评价置钉的准确性。结果16个枢椎椎弓根置钉过程中,方向出现偏差(横突孔突破)1个,失败率为6.25%。结论目标椎弓根的容积三维重建、置钉路径可视化设计和虚拟演示,使操作过程简单、直观而精确,不需要线形和角性参数的测量;加上导向抓持装置提供的稳定性,使该技术具有很好的临床应用前景。  相似文献   
24.
25.
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   
26.
患者女,48岁。两年前无明显诱因出现轻微进食梗噎感,抬头时加重,未予治疗。近半年,梗噎感加重,并出现胸闷、咳嗽,痰中带血,遂来我院就诊。胸部CT显示:左后纵隔食管后方见一长条形低密度影,密度不均,其上方见环形斑  相似文献   
27.
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   
28.
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   
29.
30.
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   
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