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   1980篇
  免费   42篇
  国内免费   15篇
耳鼻咽喉   8篇
儿科学   16篇
妇产科学   13篇
基础医学   36篇
口腔科学   5篇
临床医学   198篇
内科学   47篇
皮肤病学   4篇
神经病学   28篇
特种医学   26篇
外科学   360篇
综合类   602篇
预防医学   131篇
眼科学   2篇
药学   517篇
  1篇
中国医学   12篇
肿瘤学   31篇
  2023年   8篇
  2022年   14篇
  2021年   13篇
  2020年   14篇
  2019年   27篇
  2018年   30篇
  2017年   46篇
  2016年   39篇
  2015年   44篇
  2014年   134篇
  2013年   131篇
  2012年   175篇
  2011年   172篇
  2010年   151篇
  2009年   141篇
  2008年   139篇
  2007年   147篇
  2006年   104篇
  2005年   97篇
  2004年   77篇
  2003年   47篇
  2002年   43篇
  2001年   33篇
  2000年   27篇
  1999年   22篇
  1998年   19篇
  1997年   16篇
  1996年   17篇
  1995年   6篇
  1994年   14篇
  1993年   14篇
  1992年   6篇
  1991年   5篇
  1990年   9篇
  1989年   3篇
  1988年   5篇
  1987年   5篇
  1986年   6篇
  1985年   2篇
  1983年   4篇
  1982年   5篇
  1981年   2篇
  1980年   2篇
  1979年   2篇
  1978年   6篇
  1977年   3篇
  1976年   3篇
  1975年   3篇
  1974年   2篇
  1972年   1篇
排序方式: 共有2037条查询结果,搜索用时 31 毫秒
1.
目的:探讨异丙酚和芬太尼混合液静脉麻醉、笑气吸入麻醉及2%利多卡因宫颈局部浸润麻醉三种镇痛方法在人工流产手术中的疗效比较。方法:自2003年8月至2004年1月对236例妇科门诊早孕要求终止妊娠的妇女实施无痛人工流产术。随机分成3组。A组:异丙酚+芬太尼静脉麻醉(85例);B组:N2O(笑气)吸入麻醉(88例);C组:2%利多卡因宫颈局部浸润麻醉(63例),观察人流术中其镇痛效果并对疼痛进行分级。结果:A组85例100%可达到完全不痛(疼痛分级为0级);B组65.90%可达到完全不痛,Ⅰ级23.86%,Ⅱ级9.09%,Ⅲ级1.15%;C组0例可达到完全不痛,Ⅰ级63.49%,Ⅱ级30.16%,Ⅲ级6.35%。结论:受术者如无心肺疾患及人流禁忌证,无痛人工流产术应选择异丙酚+芬太尼静脉麻醉可达到完全无痛,痛苦最小。  相似文献   
2.
We compared rates of motor blockade, analgesia, adverse effects and patient satisfaction of 0.1% ropivacaine+fentanyl versus 0.2% ropivacaine-alone in a randomized, controlled trial. Fifty-four women who had undergone abdominal hysterectomy were randomly allocated into two groups to receive an epidural block at L1–2 or L2–3: group R received 0.2% ropivacaine-alone and group RF received 0.1% ropivacaine plus 2 μg fentanyl/ml, both at 8 ml/h. Rescue analgesia was provided via a morphine-loaded PCA device. Motor blockade (using a modified Bromage scale), pain intensity (visual analogue scale (VAS)), morphine consumption, level of sensory blockade and adverse effects, were measured at 4, 8 and 21 h after infusion. Patient satisfaction with pain management was assessed at the end of the study. The rates of motor blockade were not different at 8 h after infusion but at 21 h, group RF had significantly less motor blockade than group R. There were no differences in VAS, level of sensory blockade, adverse effects and patient satisfaction. Morphine consumption at each measurement was comparable but the total amount used by group RF was less than group R (12 mg versus 20 mg, P=0.049). Therefore, 0.1% ropivacaine with fentanyl 2 μg/ml appears to offer advantages over 0.2% ropivacaine-alone.  相似文献   
3.
朱友成    C.Prenant    C.Crouzel    池志强 《药学学报》1994,29(11):823-828
羟甲芬太尼(I)是一个新的高强度高选择性阿片μ受体激动剂。本文用cis-A-N-[1-(2-羟基-2-苯乙基)-3-甲基-4-哌啶基]-苯胺(II)或cis-N-[1-(苯甲酰甲基)-3-甲基-4-哌啶基]-苯胺(III)作为前体合成了[11C]-羟甲芬太尼,以便用正电子发射断层扫描(PET)来观察μ受体。通过水解cis-A-羟甲芬太尼(I)和cis-N-[1-(苯甲酰甲基)-3-甲基-4-哌啶]-N-苯基丙酰胺(cis-IV)的4-N-丙酰基分别获得II和III。溴乙烷的格氏试剂与回旋加速器产生的[11C]-二氧化碳反应后继而直接加入邻苯二甲酸二酰氯和2,6-二叔丁基吡啶生成同位素标记中间体[11C]-丙酰氯。[11C]-丙酰氯与OH-前体(II)反应后再经HPLC分离纯化直接得[11C]-羟甲芬太尼;[11C]-丙酰氯与酮-前体(III)反应后,再用硼氢化钠甲醇溶液处理,然后进行HPLC分离纯化得[11C]-羟甲芬太尼。两种方法均可获得ll.1~14.8GBq/μmol的特异性放射化学纯[11C]-羟甲芬太尼。总共耗时为40~50min(EOB)。  相似文献   
4.
200例择期胆囊切除+术中胆道造影患者分二组;芬太尼17ug/kg静注(F组,n=100)、哌替啶1mg/kg静注。评价两种麻醉性镇痛药致Oddi括约肌痉挛的发生率,结果:8例病人造影剂不能通过Oddi括约肌、十二指肠不显影,胆总管下端显示“鸟嘴样”或“假结石”影像,后者3例病人胆总管探查阴性,静注纳络酮0.4mg后,全部病例造影剂顺利进入十二指肠。结论:硬膜外麻醉辅用小剂量芬太尼/哌替啶时Odd  相似文献   
5.
目的 采用权重配方法探讨腹腔镜手术病人咪达唑仑、芬太尼、异丙酚复合麻醉诱导的优化配伍方案。方法选择ASAⅠ或Ⅱ级择期腹腔镜手术病人60例,男34例,女26例,年龄31~55岁。诱导药物的低效量和足量分别确定为咪达唑仑0.02、0.06mg/kg,芬太尼2、6μg/kg,异丙酚0.5、1.5mg/kg。根据权重配方法,将病人随机分配至3种药物不同剂量组合的6个配伍组(n=10)。连续监测脑电双频谱指数(BIS)、心率(HR)、平均动脉压(MAP)、脉搏血氧饱和度(SpO2)。各组依次静脉注射相应剂量咪达唑仑、芬太尼、异丙酚和罗库溴铵0.6mg/kg行麻醉诱导和气管插管。记录诱导前即刻、异丙酚注入后1、2min、插管即刻、插管后1、3、5、7min的BIS、MAP及HR。按权重配方法的剂量优化原则评判复合药效,分析各组份药的重要程度及相互作用的性质。结果以BIS为评价指标,当咪达唑仑0.06mg/kg、芬太尼5μg/ks、异丙酚1.0mg/kg配伍时,异丙酚为主药,异丙酚与咪达唑仑和芬太。尼具有相加性作用;以MAP为评价指标,当咪达唑仑0.06mg/kg、芬太尼5μg,kg、异丙酚1.5mg/kg配伍时,异丙酚为主药,异丙酚与咪达唑仑具有协同性作用,异丙酚与芬太尼具有相加性作用;以HR为评价指标,当咪达唑仑0.06mg/kg、芬太尼5μg/kg、异丙酚1.0mg/kg配伍时,芬太尼为主药,异丙酚与咪达唑仑和芬太尼具有协同性作用。结论腹腔镜手术病人咪达唑仑、芬太尼、异丙酚复合麻醉诱导在维持镇静方面为相加作用,在维持血液动力学稳定方面为协同作用;优化配伍方案为咪达唑仑0.06mg/kg、芬太尼5μg/kg、异丙酚1.5mg/kg。  相似文献   
6.
7.
国产注射用盐酸瑞芬太尼有效性和安全性的评价   总被引:252,自引:4,他引:248  
目的 采用随机、对照、双盲、多中心的Ⅱ期临床试验,评价国产注射用盐酸瑞芬太尼的有效性和安全性。方法201名受试者分成两组:对照组使用静脉芬太尼(2.5μkg诱导,0.03μg·kg-1·min-1维持)复合吸入66%氧化亚氮麻醉,试验组使用静脉瑞芬太尼(2μg/kg诱导,0.2μ·kg-1·min-1维持)复合吸入66%氧化亚氮麻醉。药物有效性的观察指标有:手术刺激时的应激反应,如血压、心率、流泪、麻醉质量。安全性的观察指标有:血压和心率、麻黄碱、阿托品、纳洛酮、乌拉地尔的使用量、手术失血量、心电图变化、术前和术后48 h内血中ALT、AST、肌酐、尿素氮、停止麻醉到可以拔除气管导管的时间、拔除气管导管前的PETCO2或PaCO2、停止麻醉(关闭氧化亚氮)后呼唤名字可以睁眼时间、术后送往麻醉恢复室或ICU情况以及不良事件。结果 瑞芬太尼与芬太尼在本试验剂量下,药效作用相似,但镇痛作用瑞芬太尼强于芬太尼,停止输注后其作用消退快于芬太尼。结论 国产瑞芬太尼用于全麻可产生良好的镇痛作用,且具有与芬太尼相同的安全性。  相似文献   
8.
Cardiovascular depression occuring when diazepam is combined with fentanyl has been investigated using the benzodiazepine antagonist RO15-1788 in the dog.After the initial administration of fentanyl (40mcg/kg), the mean arterial pressure (MAP) decreased to 89% of its control value. Following the administration of diazepam (1.2mg/kg), the MAP and the total peripheral resistance (TPR) decreased significantly, to 75% and 83% of their control values respectively. After the administration of RO15-1788 (0.4mg/kg), the MAP increased significantly to 90% and the TPR to 102% of their control values and, lastly, the administration of naloxone (40mcg/kg) increased the MAP to 108% of its control value. No relationship was found between the changes in the catecholamines and the changes in the MAP after the administration of fentanyl, diazepam, and RO15-1788.The mechanism of circulatory depression when diazepam was used with fentanyl is interpreted as being a peripheral vasodilatory effect of diazepam acting by way of the benzodiazepine receptors since RO15-1788 was found to antagonize this effect.(Sone T, Kato T, Tsukahara I et al.: The effect of RO15-1788 on cardiovascular depression caused by fentanyl and diazepam. J Anesth 2: 69–76, 1988)  相似文献   
9.
We developed a clinical neurologic and behavioral scoring system composed of 10 items to measure the post-operative pain levels in infants: (1) sleep during preceeding hour, (2) facial expression of pain, (3) quality of cry, (4) spontaneous motor activity, (5) Spontaneous excitability, (6) flexion of fingers and toes, (7) sucking, (8) global evaluation of tone, (9) consolability and (10) sociability. Using this system, a group of infants ranging from one to seven months in age and undergoing minor surgical procedures was studied. The infants were randomly assigned to two groups: Group I received Fentanyl intravenously (3 g/kg) prior to surgery, and Group II received a placebo. The infants then were studied post-operatively in the recovery room at 30, 60, 90 and 120 min intervals. Over the entire post-operative observation period, 54% of the infants in Group I had satisfactory analgesia compared to 18% in Group II. There were no significant differences in Group I and Group II in oxygenation, carbon dioxide elimination, blood pressure, heart rate or temperature.  相似文献   
10.
Summary There was stereospecific binding of 3H-lofentanil (K D value = 1.53 nM) to membranes of neuroblastoma-glioma NG 108-15 cells which are known to bear high affinity binding sites for enkephalin derivatives (-opiate receptor subtype). There was no high affinity specific binding of the -opiate specific ligand 3H-sufentanil. The specific binding of 3H-lofentanil to -opiate receptor subtype was down-regulated (decrease in B max value without change in the K D value) after prolonged incubation of the cells in the presence of leu- and met- enkephalin (0.1 M). There was no down-regulation of the opiate receptors (3H-lofentanil and 3H-d-ala-d-leu-enkephalin specific binding) after incubation of NG 108-15 cells with drugs from the fentanyl series (alfentanil or sufentanil).In cultured neurones from rat forebrain (15 day old embryos), the 3H-lofentanil binding was specific with high affinity (K D: 0.048 nM) and a slow dissociation rate similar to that in adult rat cortex. Drugs of the fentanyl series (4-anilino-piperidines) were potent displacers whereas agonists of the - (enkephalin derivatives), (phencyclidine, haloperidol, 3-hydroxyphenyl-propylpiperidine) or K- (U 50488) opiate sites had a low affinity (K i > 0.5 M) for 3H-lofentanil specific binding sites. Since there was also specific binding of 3H-sufentanil, the opiate receptors in cultured neurones seem to be mainly of the -subtype and this is consistent with the ontogeny of opiate receptors subtypes. These receptors were down-regulated after incubation in the presence of etorphine, sufentanil and alfentanil but not enkephalin derivatives.These results strongly suggest specific binding of 3H-sufentanil and 3H-lofentanil mainly to the so-called -opiate receptors in cultured neurones and a specific binding of 3H-lofentanil to lower affinity -opiate receptors in neuroblastoma-glioma cells. The down-regulation of the -opiate binding sites in cultured neurones and that of the -site in neuroblastoma × glioma hybrid cells were dose-and temperature-dependent, induced by the corresponding high affinity agonists and prevented by naloxone. Morphine did not induce down-regulation of or receptor sites, possibly because of a partial antagonist effect on both receptor subtypes. Send offprint requests to J. M. Maloteaux at the above address  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