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1.
BACKGROUNDHepatectomy with inflow occlusion results in ischemia-reperfusion injury; however, pharmacological preconditioning can prevent such injury and optimize the postoperative recovery of hepatectomized patients. The normal inflammatory response after a hepatectomy involves increased expression of metalloproteinases, which may signal pathologic hepatic tissue reformation. AIMTo investigate the effect of desflurane preconditioning on these inflammatory indices in patients with inflow occlusion undergoing hepatectomy.METHODSThis is a single-center, prospective, randomized controlled trial conducted at the 4th Department of Surgery of the Medical School of Aristotle University of Thessaloniki, between August 2016 and December 2017. Forty-six patients were randomized to either the desflurane treatment group for pharmacological preconditioning (by replacement of propofol with desflurane, administered 30 min before induction of ischemia) or the control group for standard intravenous propofol. The primary endpoint of expression levels of matrix metalloproteinases and their inhibitors was determined preoperatively and at 30 min posthepatic reperfusion. The secondary endpoints of neutrophil infiltration, coagulation profile, activity of antithrombin III (AT III), protein C (PC), protein S and biochemical markers of liver function were determined for 5 d postoperatively and compared between the groups.RESULTSThe desflurane treatment group showed significantly increased levels of tissue inhibitor of metalloproteinases 1 and 2, significantly decreased levels of matrix metalloproteinases 2 and 9, decreased neutrophil infiltration, and less profound changes in the coagulation profile.  During the 5-d postoperative period, all patients showed significantly decreased activity of AT III, PC and protein S (vs baseline values, P < 0.05). The activity of AT III and PC differed significantly between the two groups from postoperative day 1 to postoperative day 5 (P < 0.05), showing a moderate drop in activity of AT III and PC in the desflurane treatment group and a dramatic drop in the control group. Compared to the control group, the desflurane treatment group also had significantly lower international normalized ratio values on all postoperative days (P < 0.005) and lower serum glutamic oxaloacetic transaminase and serum glutamic pyruvic transaminase values on postoperative days 2 and 3 (P < 0.05).   Total length of stay was significantly less in the desflurane group (P = 0.009).CONCLUSIONDesflurane preconditioning can lessen the inflammatory response related to ischemia-reperfusion injury and may shorten length of hospitalization.  相似文献   
2.
目的探讨术前面罩预适应对降低患儿术前焦虑的作用,并比较不同实施者的影响。方法纳入全麻下行腹腔镜疝囊修补或鞘状突高位结扎手术患儿105例,男81例,女24例,年龄2~7岁,BMI 18~23 kg/m~2,ASAⅠ或Ⅱ级。患儿随机分为三组:术前1 d由父母对患儿实施面罩预适应组(P组,n=37),术前1 d由麻醉科医师对患儿实施面罩预适应组(A组,n=35),不实施面罩预适应组(C组,n=33)。采用改良耶鲁焦虑量表(mYPAS)分别于进入等待区(T_0)、与父母分离进入手术室时(T_1)、麻醉诱导时(T_2)、麻醉苏醒时(T_3)评估患儿焦虑程度,T_2时采用诱导合作量表(ICC)和面罩接受度评分(MAS)评估患儿诱导时的依从性。结果与T_0时比较,T_1时三组mYPAS评分均明显升高(P0.05)。与T_1时比较,T_2时三组mYPAS评分明显升高(P0.05)。与T_2时比较,T_3时三组mYPAS评分明显降低(P0.05)。T_1—T_3时P组和A组mYPAS评分明显低于C组(P0.05),T_2时P组mYPAS评分明显低于A组(P0.05)。T_2时P组和A组ICC评分明显低于C组,且P组明显低于A组[P组(3.6±1.6)分,A组(4.6±1.8)分,C组(5.5±1.8)分,P0.05]。T_2时P组和A组MAS评分明显高于C组[P组(2.7±0.9)分,A组(2.8±0.8)分,C组(2.0±0.8)分,P0.05],而P组和A组差异无统计学意义。结论面罩预适应能有效降低患儿术前焦虑,由父母术前1 d实施更能有效减轻患儿诱导时焦虑。  相似文献   
3.
4.
Background and aimsPreconditioning using different protocols has been tested to prevent antibody mediated rejection (ABMR) individually for ABO and HLA incompatibility. However, simultaneous presence of both barriers is still less explored. The aim of this study was to report outcomes of institutional desensitization protocol in renal transplant recipients with simultaneous ABO and HLA incompatibility.Materials and methodsThis was a retrospective study conducted from October 2015 to December 2018. All patients with a clinical diagnosis of dialysis dependent chronic kidney disease (CKD), who were prospective coexistent HLA and ABO incompatible renal transplant recipients were included in the study. Patients were followed up and graft function and patient survival was assessed at 1 y from the date of transplant.ResultsMedian and mode baseline anti-A titers were 64, while median and mode baseline anti-B titers were 256. All recipients were discharged by tenth postoperative day. None of the patients had any bleeding complications. Post transplant infection rate was found to be 20 %. A total of 54 therapeutic plasma exchange (TPE) procedures were performed before transplant and 8 were performed after transplant. Graft survival and patient survival was 100 % at 3, 6, 9, and 12 months. Range and mean follow-up period was 15–42 months and 23 months respectively. Mean glomerular filtration rate (GFR) at 1 y using the CKD-EPI equation was 85.25 ± 13.76 mL/min. Biopsy proven ABMR was observed in one case only which was managed with TPE and immunosuppression.ConclusionSimultaneous ABO and HLA incompatibility in renal transplant recipients can be managed successfully with adequate preconditioning and careful monitoring.  相似文献   
5.
王群 《中国卒中杂志》2015,10(2):135-140
卒中是第3位常见的致死原因,给社会和经济带来沉重的负担。针对卒中的治疗多集中在
急性期,而卒中恢复期的治疗尚无有效方法。有关药物治疗或无效或存在不良影响,相应的神经保
护和大脑修复仍然是主要的尚未实现的医疗需求。近年来,大脑保护自身免受伤害性刺激以及修复
内源性修复损伤越来越受关注。其中,对预适应的研究(也被称为诱导耐受性)已产生多种有希望治
疗急性颅脑损伤的方法。一方面,预适应可以识别那些被诱导出的内源性保护或再生机制;另一方面,
对于那些预期会发生缺血性事件的人群(如接受过脑部手术、短暂性脑缺血发作或蛛网膜下腔出血
的患者),预适应可以作为一种治疗手段来诱导出耐受性。  相似文献   
6.
In response to the three petitions by Carol S. Marcus, Mark L. Miller, and Mohan Doss, dated February 9, February 13, and February 24, 2015, respectively, the Nuclear Regulatory Commission (NRC or the Commission) has announced that it is considering assessing its choice of dose–response model, the Linear No-Threshold (LNT) model, for exposure to ionizing radiation. This comment is designed to assist the Commission in evaluating the merits of a review of the default dose–response model it uses as the basis for the Standards for Protection against Radiation regulations. It extends the petitioners' argument in favor of reexamining the default hypothesis (LNT) and taking consideration of low-dose hormesis for two main reasons: 1) Failure to review the LNT hypothesis may jeopardize the NRC's mission to protect public health and safety; and 2) The National Research Council's guidelines for choosing adequate defaults indicate that the choice of low-dose default model is due for a reevaluation.  相似文献   
7.
目的:比较七氟醚预处理和后处理在经体外循环下(CPB)法洛氏四联症(TOF)根治手术中对患者心肌保护的效果并比较两种方法的效果差异。方法选取行法洛氏四联症根治手术患者48例,采用随机数字表法,将其分为3组,对照组Ⅰ(n=16),2%七氟醚预处理组Ⅱ(n=16),2%七氟醚后处理组Ⅲ(n=16),其中对照组全程采取全凭静脉麻醉。采集手术切皮时,手术结束后6,12,24 h,测定患者血浆心肌肌钙蛋白I(cTnI)的浓度,并记录主动脉阻断时间,体外循环时间,手术时间,ICU住院时间,机械通气时间,正性肌力药物使用情况。结果3组患者一般资料、术中各指标比较差异无统计学意义(P>0.05)。各组手术切皮前血浆心肌肌钙蛋白I(cTnI)(基础值)差异无统计学意义(P>0.05)。具有可比性,与1组比较,2组,3组在手术结束后4,12,24 h血浆心肌肌钙蛋白测定值降低,差异有统计学意义(P<0.05)。术后临床观察指标具有统计学意义(P<0.05)。2组3组在各时间点测定值差异无统计学意义(P>0.05)。结论在本研究条件下,以血浆心肌肌钙蛋白I(cTnI)作为心肌保护的指标时,七氟醚缺血预处理组和七氟醚缺血后处理组均能显著降低心肌肌钙蛋白的浓度,减轻心肌缺血再灌注损伤,从而起到心肌保护作用,而两种处理方法在心肌保护方面未见明显差异。  相似文献   
8.
黄茜  王萍  陶明哲 《广州医药》2014,45(2):63-66
糖尿病是心血管疾患的独立危险因素,糖尿病患者发生急性心肌梗死后的病死率明显升高.缺血预处理(IPC)、缺血后处理(IPOST)、远端肢体/组织预处理(RIC)以及麻醉药物预处理(APC)等“预处理”策略,已被证明在非糖尿病患者能够发挥明显的心肌保护作用,近年有研究认为,在Ⅱ型糖尿病患者其心肌保护作用被减弱或者消失.现就“预处理”技术对Ⅱ型糖尿病患者缺血性心肌损害的保护作用及其机制的研究进展予以综述.  相似文献   
9.
Bovine and porcine pericardia are currently used for manufacturing prosthetic heart valves: their design has become an increasingly important area of investigation in parallel with progressively expanding indications for the transcutaneous approach to heart valves replacement. Before being cut and shaped, pericardial tissues are expected to be properly characterized. Actually, the mechanical assessment of these biomaterials lacks standardized protocols. In particular, the role of preconditioning for achieving a constant mechanical response of tissue samples is still controversial. In the present work, the mechanical response to uniaxial load of native bovine and porcine pericardia, with and without preconditioning was assessed; moreover, the mechanical behavior of pericardia was investigated and explained. It was demonstrated that: (i) pericardial tissue samples hold memory of the loading history but just within the extent of the deformation applied; (ii) the behavior of native bovine and porcine pericardia in response to load is explained by a mechanism based on the additive recruitment of collagen fibers; (iii) the current concept that plasticity is absent in pericardium has to be at least in part reconsidered.  相似文献   
10.
IntroductionPerinatal asphyxia (PA) is a major cause of neonatal mortality and morbidity. Research has shown that in rats fetal asphyxia (FA) can provoke neuroprotection against a subsequent more severe perinatal asphyctic insult. This is called fetal asphyctic preconditioning (PC). Our objective was to investigate alterations in the placental inflammatory phenotype associated with PC.MethodsFA was induced in the rat at embryonic day 17 by reversibly clamping the uterine circulation and PA was induced at birth by submersion of the uterine horns in a saline bath for 19 min. The effect of PC was studied by inducing FA at E17, followed by PA at E21. Placental TNF-α, IL-1β, IL-6 and IL-10 mRNA and protein levels were measured by qPCR and ELISA.ResultsIL-1β mRNA increased in the labouring FA group, but IL-1β protein decreased after both FA and PA. In the PC group, IL-1β mRNA and protein levels were similar to controls. IL-6 protein increased 6 h after FA, however decreased 24 h after FA. IL-6 mRNA was higher in the labouring PA group. IL-10 protein decreased 24 h after FA. At birth, IL-10 mRNA increased in the PA group; however, IL-10 protein decreased in both the PA and the FA group. In the PC group, IL-10 mRNA and protein were similar to control levels.DiscussionDepleted protein concentrations of IL-10 and IL-1β after one single asphyctic insult were reversed after fetal asphyctic PC. In addition, PC placentas showed less up-regulation of IL-6 mRNA compared to the PA ones. This modulated placental inflammatory phenotype might contribute to the improved neonatal outcome showed after fetal asphyctic PC.  相似文献   
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