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   76542篇
  免费   5210篇
  国内免费   1633篇
耳鼻咽喉   3103篇
儿科学   893篇
妇产科学   1511篇
基础医学   1892篇
口腔科学   3141篇
临床医学   7135篇
内科学   7361篇
皮肤病学   698篇
神经病学   2541篇
特种医学   1241篇
外国民族医学   20篇
外科学   26514篇
综合类   10270篇
现状与发展   6篇
一般理论   2篇
预防医学   2766篇
眼科学   4650篇
药学   3026篇
  175篇
中国医学   849篇
肿瘤学   5591篇
  2024年   265篇
  2023年   2076篇
  2022年   3180篇
  2021年   4179篇
  2020年   4136篇
  2019年   3530篇
  2018年   3366篇
  2017年   2903篇
  2016年   2898篇
  2015年   2950篇
  2014年   5798篇
  2013年   5408篇
  2012年   4349篇
  2011年   4571篇
  2010年   3623篇
  2009年   3443篇
  2008年   3289篇
  2007年   3284篇
  2006年   2860篇
  2005年   2514篇
  2004年   2181篇
  2003年   1752篇
  2002年   1382篇
  2001年   1318篇
  2000年   1135篇
  1999年   1035篇
  1998年   857篇
  1997年   810篇
  1996年   605篇
  1995年   492篇
  1994年   435篇
  1993年   350篇
  1992年   295篇
  1991年   293篇
  1990年   198篇
  1989年   193篇
  1988年   194篇
  1987年   194篇
  1986年   153篇
  1985年   171篇
  1984年   160篇
  1983年   103篇
  1982年   109篇
  1981年   97篇
  1980年   77篇
  1979年   45篇
  1978年   34篇
  1977年   32篇
  1976年   26篇
  1975年   20篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
老年病人上腹部手术后应用PCEA的临床效果观察   总被引:1,自引:1,他引:0  
目的 观察老年人上腹部术后病人自控硬膜外镇痛 (PCEA)的疗效及对内分泌功能的影响。方法 6 3例择期行胃癌根治术的老年患者 ,ASAⅠ -Ⅱ级 ,随机分为 3组 (每组 2 1例 ) :A组术后行硬膜外镇痛 (PCEA) ;B组术后行静脉镇痛 (PCIA) ;C组术后按需肌肉注射哌替啶镇痛 ;对比术后镇痛效果并分别于麻醉前 ,切皮后 90分钟 ,术后 6 0及 1、2、3天分别抽取外周静脉血测定血糖、胰岛素、皮质醇、肾上腺素浓度。结果 A、B组镇痛效果均满意 ,C组镇痛效果欠佳 ,综合镇痛质量A组优于B组优于C组 ;3组于切皮后 90分钟血皮质醇、血糖浓度均升高 ,但A组低于C、B两组 (P <0 .0 5 ) ,术后 6 0分钟均达高峰 (P <0 0 1) ,术后 2 4至 4 8小时虽有下降 ,但仍明显高于麻醉前水平 (P <0 0 5 ) ;血胰岛素水平 ,A、B组术后 3天无明显变化 ,C组术后第 1、2天升高显著 (P <0 .0 1及P <0 .0 5 ) ;肾上腺素A、B组术后无明显升高 ,C组术后 6 0分钟明显升高 ,于术后 3天仍未恢复至术前水平。结论 老年病人上腹部术后PCIA及PCEA均能达到优良的镇痛效果 ,PCEA能有效地抑制术后机体的应激反应 ,有利于术后病人的恢复。  相似文献   
82.
Summary During a period of 17 years (from 1976 till now) 45 patients with giant gliomas of the chiasma and the IIIrd ventricle out of a total amount of 120 patients with hypothalamic gliomas were operated. The following classification of tumours was used: I) tumours with predominant anterior growth; II) tumours which infiltrate chiasma and penetrate into the IIIrd ventricle; III) gliomas of the floor of the IIIrd ventricle and the chiasma, growing into the ventricle cavity; IV) tumours of the chiasma, optic tract and thalamus. The authors come to the conclusion, that surgical removal of giant tumours of the chiasma and the IIIrd ventricle, though risky, may result in an improvement or stabilisation of visual functions (77%) and a long period free from recurrencies (9.5%). The postoperative period is relatively favourable and the mortality is low (6%). The main contraindication in our opinion is a wide infiltration of adjacent brain structures by the tumour and spreading along both optical tracts. We consider the giant size of a tumour in itself a sufficient indication for surgery.  相似文献   
83.
84.
脑电双频指数用于门诊无痛内镜检查的临床研究   总被引:6,自引:0,他引:6  
目的 观察脑电双频指数 (BIS)监测对门诊无痛内镜检查病人麻醉过程及恢复的意义。方法  12 0例择期在丙泊酚 芬太尼静脉麻醉下行胃镜检查的门诊病人 ,随机分为BIS监测组 (A组 )与常规监测组 (B组 ) ,每组 6 0例。静脉给予芬太尼 1μg/kg、丙泊酚 0 5mg/kg负荷量后 ,丙泊酚的维持量A组根据BIS值 (4 5~ 6 0 )调节 ,B组仅根据临床体征调节。记录丙泊酚用量、术中反应、胃镜检查时间及留观时间等。结果 两组间一般资料及麻醉前MAP、HR、SpO2 、BIS均无显著性差异(P >0 0 5 )。丙泊酚用量A组明显少于B组 ,留观时间A组显著短于B组 (P <0 0 1)。MAP在麻醉诱导入睡后和插镜时两组均有下降 ,但A组降幅低于B组 (P <0 0 1)。不良反应发生率A组明显少于B组 (P <0 0 1)。结论 BIS监测用于门诊麻醉对预防麻醉药用量不足或逾量 ,减轻血液动力学改变 ,避免术中肢动与知晓有重要意义 ,有利于提高麻醉安全 ,减少并发症。  相似文献   
85.
自1990年以来收治直径在2-5.6cm的大、巨型垂体腺瘤33例。依肿瘤生长形态与扩展范围将其简略分为三种类型。A型:瘤体位于鞍内或侵入蝶窦;B型;瘤体呈椭圆形或哑铃向鞍上扩展,三脑室明显移位抬高;C型:瘤体巨大侵入三脑室阻塞室间孔或明显的鞍周扩展。  相似文献   
86.
Summary A retrospective analysis of 183 consecutive patients operated on for ruptured cerebral aneurysms and surviving at least one year revealed appearance of postoperative epilepsy in 14 cases (8 per cent) on an average of 10 months (range 0–23 months) after the operation. Factors associated with the development of secondary epilepsy were localization of the aneurysm on the middle cerebral artery, temporary clipping intraoperatively, wrapping technique to treat the aneurysm, and vasospasm seen on the postoperative control angiogram. Intraoperative and/or postoperative ischaemia seems to be the crucial phenomenon favouring the development of epilepsy. Identification of the risk factors may help to focus the anti-epileptic prophylaxis in cases prone to develop seizures.  相似文献   
87.
Esotropic patients whose angle of strabismus has been corrected by prisms frequently increase their angle deviation to compensate for the prismatic correction. This sensorio-motorial reaction to prism correction has been given the name of anomalous movements (a.m.). Quantification of a.m. has been made according to the amount of prisms that an esotropic patient is capable of compensating for (progressive prism compensation test - p.p. test). Some esodeviation does not compensate for any prisms at all since a.m. have not yet developed. Other cases compensate for as much as 40 or 60 prism diopters and more of over-correction of the angle deviation and they therefore have powerful a.m. The interference of these innervational forces acting on the medial recti to corrective surgery has been studied in 126 operated esotropic patients. A significant decrease from the expected surgical result (p < 0.001) has been found in patients having powerful a.m., as can be judged by the p.p. test. It is believed that a.m. are an important drawback contributing to vitiate any formula on the amount of muscle surgery to be performed in patients having no possibilities of restoring normal binocular vision.Practical advice on how to eliminate this drawback and theoretical reasoning on the significance of a.m. are offered.  相似文献   
88.
BACKGROUND: Our objective was to analyze retrospectively our experience with 19 patients who had metastatic germ cell testicular tumor and had undergone resection of pulmonary metastases following chemotherapy. We wished to determine the necessity of thoracic surgery on these patients. METHODS: Of 103 patients in need of postchemotherapeutic surgery for metastatic germ cell testicular tumors, 19 patients (mean age 31) underwent surgery for thoracic masses following cis-platin based chemotherapy. Resection of pulmonary metastases was performed on patients with normal tumor markers after chemotherapy, who did not achieve complete radiological remission. Histopathological findings, correlation with the pathology of abdominal surgery and probable prognostic factors for disease-free and overall survivals were evaluated. RESULTS: Disease-free and overall survival rates were 14/19 (73%) and 16/19 (84%), respectively, within a median follow-up time of 30 months (15-212 months). Patients with and without viable tumor cells in their thoracic histopathological specimen had 40% and 85% disease-free survival rates, respectively (P < 0.05). Eight patients had both abdominal and thoracic postchemotherapy surgery. Only two (25%) of these patients had the same histopathological features at both sites. CONCLUSIONS: All patients with residual thoracic masses must be considered candidates for surgery, because there are no predictive factors to determine the thoracic pathology without surgery. With the resection of the pulmonary metastases only, surgery can be performed without significant morbidity and is essential to select patients for further chemotherapy, to remove all visible masses and to provide histopathological confirmation. Patients with viable tumor cells in the thoracic surgical specimen have a poor prognosis.  相似文献   
89.
对205例甲状腺手术进行分析,其发病情况与资料报道基本相符。各种并发症的发生率未超过1%,无手术死亡,术后无甲状腺危象发生,与60年代以前相比已大为降低。  相似文献   
90.
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