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1.
在各种危重病员的抢救或行各种大手术的输液方法,是医疗工作中关键的问题。但在这问题上看法和做法都有一些分歧,恰当地应用这种疗法是会起到很好的效果,若使用不当也可以带来一些相反地的作用。在讨论这个问题时,愿就下列几个问题探讨其实质上的复杂性。一、输液疗法的病理生理应用输液疗法之前,应该详细了解有关的病理生理方面问题。 1.心排血量:心排血量主要取决于四个因素(图1)。 a.前负荷:右心室舒张末期容量来自静脉回流。静脉系潴血量约相当于全身血容量的80%左右(图  相似文献   
2.
细胞凋亡与肝脏缺血/再灌注损伤   总被引:1,自引:0,他引:1  
细胞凋亡是肝缺血再灌注过程中的病理特征之一,本文论述在肝缺血/再灌注损伤中肝细胞凋亡的发生机制。  相似文献   
3.
Objective To investigate the effects of pressure -controlled ventilation (PCV) and volume -controlled ventilation (VCV) on obese patients undergoing gynecologic laparoscopic surgery by evaluating hemodynamics and respiratory parameters, and arterial oxygenation. Methods Forty obese patients undergoing gynecological laparoscopic surgery were randomly divided into PCV and VCV group (n=20). Patients were all implemented into the program of total intravenous anesthesia, and ventilated with different modes.End-tidal carbon dioxide partial pressure (PETCO2) was maintained between(35-45 ) mm Hg. Arterial blood was collected respectively to analyze blood gas at 5 min before anesthesia (T0), 5 min before the start of pneumoperitoneum (T1),30 min after the start of pneumoperitoneum(T2), 5 min after the end of pneumoperitoneum(T3) and at extubation(T4). Meanwhile, parameters of hemodynamics and respiratory mechanics were monitored and calculated. Results 1 、At T1,T2 and T3, PaO2 and OI (460±78,453±83,463±95)were significantly higher in PCV group (P<0.05), A-aDO2(74±25,80±30,82±26) and RI (0.32±0.08,0.33±0. 10,0.34±0.13 ) was significantly lower (P<0.05) in PCV group. 2. Compared with T0, PaCO2 at T2,T3,T4 in both groups increased significantly and PH decreased significantly (P<0.05); Compared with VCV group, PCV group had no significant difference at each time point. 3. Compared with VCV group, Ppeak(27.8±1.6)in PCV group at T2 was significantly lower(P<0.05). Conclusion The ventilation/perfusion ratio was improved and gas exchange was promoted in obese patients undergoing gynecologic laparoscopic surgery with PCV model.  相似文献   
4.
目的 比较不同年龄患者腹腔镜胆囊切除术中肾血流量的变化.方法 择期行腹腔镜胆囊切除术患者60例,年龄18~75岁,ASA分级Ⅰ或Ⅱ级,性别不限,体重48~78 kg,根据年龄分为2组(n=30):中青年组(18~60岁)和老年组(61 ~ 75岁).经口气管插管后置入食管超声探头,分别于气腹前、气腹1、5、10、15、20、30 min、气腹结束后1和5 min时,采用经食管超声心动图测量左肾动脉主干内径(RAD)和血流速度时间积分(VTI),计算左肾血流量(LRAF),记录最大下降时间点,计算最大下降百分比.结果 与气腹前比较,两组气腹各时点和气腹结束后1 min时RAD、VTI和LRAF降低(P<0.05).与中青年组比较,老年组气腹前LRAF降低,最大下降时间点延迟(P<0.05),最大下降百分比差异无统计学意义(P>0.05).结论 中青年患者和老年患者腹腔镜胆囊手术中肾血流量均发生可逆性下降;老年患者最大下降时间延迟.  相似文献   
5.
目的 比较静脉输注右美托咪定和靶控输注丙泊酚在内镜逆行性胰胆管造影(ERCP)中的作用.方法 30例ERCP患者随机分为两组:P组靶控输注(TCI)丙泊酚,D组恒速输注右美托咪定.记录不同时点的Richmond躁动镇静量表(RASS)评分,监测生命体征,并统计术中体动发生率和舒芬太尼用量.结果 D组用药后15 min、ERCP期间RASS评分均明显高于P组(P<0.05);入恢复室即刻、入恢复室后15 min的RASS评分均明显低于P组(P<0.05);但D组ERCP术中体动发生率、舒芬太尼用量均高于P组,且MAP下降,HR减慢较P组明显(P<0.05).结论 右美托咪定用于ERCP的麻醉效果与丙泊酚不等同,且血流动力学更不稳定.  相似文献   
6.
目的 探讨不同浓度七氟醚预处理对大鼠海马神经元缺氧复氧时细胞凋亡的影响及线粒体ATP敏感型钾通道(mito-KATP通道)在其中的作用.方法 新生(出生<24 h)SD大鼠,雌雄不拘,体重5~6 g,原代培养海马神经元,接种于培养孔或培养皿中,采用随机数字表法,将其随机分为7组,每组48孔和12皿,正常对照组(C组):不予任何处理;缺氧复氧组(HR组):缺氧4 h复氧24 h;6%七氟醚预处理组(S1 组)、4%七氟醚预处理组(S2 组)、2%七氟醚预处理组(S3 组):分别经6%、4%、2%七氟醚预处理后行缺氧复氧;5-羟葵酸100 μmol/L预处理组(5-HD组):经mito-KATP通道阻断剂5-羟葵酸(终浓度100 μmol/L)预处理后进行缺氧复氧;5-羟葵酸100 μmol/L+6%七氟醚预处理组(5-HD+S组):同时行5-羟葵酸和6%七氟醚预处理后进行缺氧复氧.各组以上处理结束后,测定神经元活力、凋亡率、Bcl-2和Bax蛋白的表达水平.结果 与C组比较,其余6组海马神经元活力降低,细胞凋亡率升高,Bcl-2和Bax蛋白表达上调(P<0.01);与HR组比较,S1组~S3组海马神经元活力增强,细胞凋亡率降低,Bcl-2蛋白表达上调,Bax蛋白表达下调(P<0.01),5-HD组和5-HD+S组上述指标比较差异无统计学意义(P>0.05);与S1组比较,S2组、S3组和5-HD+S组海马神经元活力降低,细胞凋亡率升高,Bcl-2蛋白表达下调,Bax蛋白表达上调(P<0.01);与S2组比较,S3组海马神经元活力降低,细胞凋亡率升高,Bcl-2蛋白表达下调,Bax蛋白表达上调(P<0.01).结论 七氟醚预处理可抑制大鼠海马神经元缺氧复氧时细胞凋亡,从而减轻神经元损伤,且呈浓度依赖性,机制可能与开放神经元mito-KATP通道,上调Bcl-2蛋白表达,下调Bax蛋白表达有关.
Abstract:
Objective To investigate the effect of preconditioning with different concentrations of sevoflurane on hypoxia-reoxygenation(H/R)-induced apoptosis in rat hippocampal neurons and the role of mitochondrial KATP(mito-KATP)channels.Methods Primary cultured hippocampal neurons isolated from newborn SD rats(<24h)of both sexes,weighing 5-6 g,were randomly divided into 7 groups with 48 wells and 12 dishes in each one:control group(C group),H/R group,preconditioning with 6%,4%and 2% sevoflurane groups(S1-3 groups),5-hydroxydecanoate(5-HD,mito-KATP channel blocker)100 μmol/L preconditioning group(5-HD group)and preconditioning with 5-HD 100 μmol/L+6% sevoflurane group(5-HD+S group).The neurons were exposed to 4 h hypoxia followed by 24 h reoxygenation. In S1-3 groups, preconditioning was performed with 6% , 4% and 2% sevoflurane respectively before H/R. In 5-HD group, preconditioning was performed with 5-HD (final concentration 100 μmol/L) before H/R. In 5-HD + S group, preconditioning was performed with 5-HD 100 μmol/L and 6% sevoflurane before H/R. The neuronal viability, apoptosis rate and expression of Bcl-2 and Bax were determined after 24 h reoxygenation.Results The neuronal viability was significantly lower,while the apoptosis rate and expression of Bcl-2 and Bax were significantly higher in the other 6 groups than in group C(P<0.01).The neuronal viability and expression of Bcl-2 were significantly higher,while the apoptosis rate and Bax expression were lower in S1-3 groups than in group H/R. There was no significant difference in the parameters mentioned above between 5-HD and 5-HD + S groups(P>0.05).The neuronal viability and expression of Bcl-2 were significantly lower, while the apoptosis rate and Bax expression were higher in S2, S3 and 5-HD + S groups than in group S1, and in group S3 than in group S2(P<0.0l) .Conclusion Sevoflurane preconditioning can inhibit H/R-induced apoptosis in rat hippocampal neurons and reduce the injury to neurons in a concentration-dependent manner, and the underlying mechanism may be related to activation of mito-KATP channels, up-regulation of Bcl-2 expression and down-regulation of Bax expression.  相似文献   
7.
目的 确定舒芬太尼复合TCI异丙酚抑制经尿道前列腺电切术(TURP)老年患者尿道镜置入反应的半数有效效应室靶浓度(EC50).方法 拟行TURP的患者22例,年龄65~79岁,体重47~81 kg,ASA分级Ⅰ~Ⅲ级.TCI异丙酚,血浆靶浓度4 μg/ml,异丙酚达到靶浓度后开始TCI舒芬太尼;采用序贯法,按照患者是否发生尿道镜置入反应确定舒芬太尼的效应室靶浓度,初始效应室靶浓度为0.3 ng/ml,相邻浓度比值为1.1.计算舒芬太尼的EC50及其95%可信区间.结果 舒芬太尼抑制尿道镜置入反应的EC50为0.23 ng/ml,95%可信区间为0.12~0.44 ng/ml.结论 复合TCI异丙酚(血浆靶浓度4 μg/ml)时,舒芬太尼抑制TURP老年患者尿道镜置入反应的EC50为0.23 ng/ml.
Abstract:
Objective To determine the half-effective target effect-site concentration (EC50 ) of sufentanil inhibiting the urethroscope insertion response when combined with propofol by target-controlled infusion (TCI) in the elderly patients undergoing transurethral resection of prostate (TURP) . Methods Twenty-two ASA Ⅰ- Ⅲ patients, aged 65 -79 yr, weighing 47-81 kg, undergoing TURP, were enrolled in the study. Anesthesia was performed with TCI of propofol and sufentanil. The target plasma concentration of propofol was 4 μg/ml. The target effect-site concentration of sufentanil was determined by up-and-down sequential trial. The initial target effect-site concentration of sufentanil was 0.3 ng/ml and the ratio of the target concentrations between the two consecutive patients was 1.1. The ECW and 95% confidence interval of sufentanil required to inhibit the response to urethroscope insertion were calculated. Results The EC50 of sufentanil required to inhibit the urethroscope insertion response was 0.23 ng/ml (95% confidence interval 0.12-0.44 ng/ml). Conclusion When combined with propofol by TCI (target plasma concentration 4 μg/ml), the EC50 of sufentanil inhibiting the response to urethroscope insertion is 0,23 ng/ml in the elderly patients undergoing TURP.  相似文献   
8.
目的 研究监护性麻醉(MAC)患者不同新鲜气流量(FGF)下经鼻咽通气管监测PETCO2与PaCO2的相关性.方法 择期在MAC下行单纯乳腺区段切除术女性患者20例,ASA Ⅰ或Ⅱ级.患者入室后依次静脉给予咪达唑仑、舒芬太尼及丙泊酚,当OAA/S为2~3分、RR为10~15次/分时,测量经鼻翼至耳垂的距离,选择经左/右侧鼻孔置入鼻咽通气管(一般为ID 7~7.5 mm)达咽部,调整鼻咽通气管位置,使得PETCO2波形为方波,随后调整FGF为1 L/min,调整10 min后,记录此时的PETCO2及测量PaCO2.按以上方法,依次调整FGF至1.5、2 L/min,分别记录相应的PET CO2及PaCO2.结果 FGF为1、1.5、2 L/min时,PETCO2与PaCO2的相关系数分别为0.927、0.925、0.852(P<0.01).结论 MAC下当OAA/S为2~3分,RR为10~15次/分时,采用鼻咽通气管保持FGF1~2 L/min,PETCO2与PaCO2显著相关.  相似文献   
9.
Objective To investigate the effects of diazoxide preconditioning combined with hypothermia on the expression of Bcl-2 and Bax during anoxia-reoxygenation in rat hippocampal neurons. Methods The hippocampal neurons isolated from newborn SD rats ( < 24 h, weighing 5-6 g) were inoculated in the culture dish or 96 well plates. The hippocampal neurons were randomly assigned into 8 groups and each group contained 36 wells or 12 dishes of neurons: normal temperature .group (group NT), diazoxide preconditioning (DP) + NT group (group DP+ NT), mild hypothermia group (group MiH) , DP + MiH group (group DP + MiH) , moderate hypothermia group (group MoH), DP + MoH group (group DP + MoH), deep hypothermia group (group DeH) and DP+DeH group (group DP+ DeH). In group DP + NT, DP + MiH, DP+ MoH and DP + DeH, diazoxide was added to the culture media, the final concentration was 100 μmol/L,and the neurons were incubated for 1 h once a day for 2 d, and then subjected to 4 h of hypoxia at 37, 34, 30 and 22℃ , respectively, followed by 48 h of reoxygenation at 37℃ . The neuronal viability, apoptotic rates and expression of Bcl-2 and Bax were determined and the ratio of Bcl-2/Bax was calculated. Results The neuronal viability was significantly higher, apoptotic rate lower, Bcl-2 expression higher, Bax expression lower and Bcl-2/Bax ratio higher in group DP + NT, MiH, MoH and DeH than in group NT ( P < 0.05). The neuronal viability was significantly higher, early apoptotic rate lower, Bcl-2 expression higher, Bax expression lower and Bcl-2/Bax ratio higher in group DP + MiH, DP + MoH and DP+ DeH than in group DP + NT ( P < 0.05), but there was no significant difference in the late apoptotic rate between group DP + MiH, DP + MoH, DP + DeH and DP + NT ( P > 0.05). The neuronal viability was significantly higher, early apoptotic rate lower, Bcl-2 expression higher, Bax expression lower and Bcl-2/Bax ratio higher in group DP+ MiH and DeH than in group MiH (P < 0.05), but there was no significant difference in the late apoptotic rate between group DP + MiH, DeH and MiH, and no significant difference in the above indices between group MoH and MiH (P > 0.05) . The neuronal viability was significantly higher, early apoptotic rate lower, Bcl-2 expression higher, Bax expression lower and Bcl-2/Bax ratio higher in group DP+ DeH than in group DP+ MiH ( P < 0.05). Conclusion Diazoxide preconditioning combined with hypothermia can attenuate the anoxia-reoxygenation injury in rat hippocampal neurons possibly through correcting the imbalance of Bcl-2 and Bax and inhibiting the early apoptosis of hippocampal neurons.  相似文献   
10.
目的评价不同浓度七氟醚静态膨肺对心肺转流(cardiopulmonary bypass,CPB)后肺气体交换及术后气管留管时间的影响。方法择期行CPB下瓣膜置换手术患者75例,男39例,女36例,年龄22~65岁,ASAⅡ或Ⅲ级。采用随机数字表法将患者随机分为三组:每组25例。CPB期间停止呼吸后,予持续静态膨胀,呼吸环路压力维持10cmH2O,膨肺气体采用空气,分别复合吸入1%七氟醚(L组)或2%七氟醚(H组),对照组(N组)不复合吸入七氟醚。分别于切皮前、CPB停机后1、3、6h抽取动脉血行血气分析。计算肺泡-动脉氧分压差[D(A-a)O_2]、呼吸指数(RI)和氧合指数(OI)。记录术后气管留管时间和ICU留观时间。结果与切皮前比较,CPB停机后1、3、6h三组D(A-a)O_2、RI明显升高(P0.05);CPB停机后1h三组OI明显降低(P0.05)。三组不同时点D(A-a)O_2、RI和OI差异无统计学意义。三组CPB停机后1、3、6h发生OI300mmHg的比例、术后气管留管时间和ICU留观时间差异无统计学意义。结论心脏瓣膜置换手术CPB期间,静态膨肺采用10cmH2O压力,复合吸入1%或2%浓度七氟醚,与单纯静态膨肺比较,不能进一步改善CPB后患者肺气体交换,不影响术后气管留管时间和ICU留观时间。  相似文献   
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