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1.
刘更夫  张远金  贺桂文  段军 《骨科》2015,6(1):32-35
目的观察联合多种技术手段、药物对骨科手术患者失血、凝血功能和血液氧合状态的影响以及实施血液保护的效果。方法选择2013年2月至2014年1月在我院就诊的271例骨科手术治疗患者,术前行储存式自体输血,术中采用控制性降压技术、稀释式或回收式自体输血技术,并使用凝血药物等;观察患者手术前后血红蛋白(hemoglobin,Hb)、红细胞比容(red blood cell specific volume,Hct)、血小板计数(blood platelets count,BPC)、活化部分凝血活酶时间(activated partial thromboplastin time,APTT)、凝血酶原时间(prothrombin time,PT)、血浆黏度、全血黏度以及混合静脉血氧分压(mixed venous blood oxygen tension,PvO2)、混合静脉血氧饱和度(mixed venous oxygen saturation,SvO2)等指标的变化,对比分析实施血液保护对患者贫血程度、凝血功能、血液流变学以及血液氧合状态的影响。结果本组病例围术期自体输血共179 010 mL,异体输血共35 000 mL,未出现输血不良反应;患者术后Hb、Hct、BPC、血浆黏度、全血黏度均低于术前,差异均有统计学意义(均P<0.05),PvO2、SvO2较术前有所升高,但差异均无统计学意义(均P>0.05),APTT、PT手术前后无明显变化,差异均无统计学意义(均P>0.05)。结论骨科围术期联合应用多种血液保护方法能明显减少失血,减少异体输血,保护血液资源,且未对患者凝血功能、氧合状态产生明显影响。  相似文献   
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The steroid hormone 17b-estradiol and the peptide hormone insulin-like growth factor (IGF)-1 independently exert neuroprotective actions in neurologic diseases such as stroke. Only a few studies have directly addressed the interaction between the two hormone systems, however, there is a large literature that indicates potentially greater interactions between the 17b-estradiol and IGF-1 systems. The present review focuses on key issues related to this interaction including IGF-1 and sex differences and common activation of second messenger systems. Using ischemic stroke as a case study, this review also focuses on independent and cooperative actions of estrogen and IGF-1 on neuroprotection, blood brain barrier integrity, angiogenesis, inflammation and post-stroke epilepsy. Finally, the review also focuses on the astrocyte, a key mediator of post stroke repair, as a local source of 17b-estradiol and IGF-1. This review thus highlights areas where significant new research is needed to clarify the interactions between these two neuroprotectants.  相似文献   
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Simon's two‐stage designs are widely used in cancer phase II clinical trials for assessing the efficacy of a new treatment. However in practice, the actual sample size for the second stage is often different from the planned sample size, and the original inference procedure is no longer valid. Previous work on this problem has certain limitations in computation. In this paper, we attempt to maximize the unconditional power while controlling for the type I error for the modified second stage sample size. A normal approximation is used for computing the power, and the numerical results show that the approximation is accurate even under small sample sizes. The corresponding confidence intervals for the response rate are constructed by inverting the hypothesis test, and they have reasonable coverage while preserving the type I error. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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目的:探讨不同剂量瑞舒伐他汀对急性冠脉综合征(ACS)合并糖尿病患者的临床疗效及对血清中高敏C反应蛋白(hs-CRP)、血糖的影响。方法选择2012年8月至2014年8月于我院心内科住院的164例ACS合并糖尿病患者,随机分为试验组和对照组,每组82例,在控制血糖和低脂饮食的基础上,试验组自入院始服用瑞舒伐他汀20 mg/d,对照组自入院始服用瑞舒伐他汀10mg/d,观察住院期间及4周12周血脂情况及肝肾功能、肌酶的变化,同时采用酶联免疫吸附法测定两组患者服用瑞舒伐他汀前后血清hs-CRP水平及血糖、HbA1c水平。结果患者住院期间及服瑞舒伐他汀4周12周后,LDL-C水平均有显著下降,差异有统计学意义(P<0.05)。转氨酶肌酶肝肾功能及肌溶解发生率方面差异无统计学意义(P>0.05)试验组与对照组治疗前后血清hs-CRP水平均显著降低,对照组入院时(19.68±12.62)mg/L,4周(12.69±10.59)mg/L,12周(10.07±9.63)mg/L;实验组入院时(19.70±12.50)mg/L,4周(11.23±8.64)mg/L,12周(8.32±7.59)mg/L,组间差异有统计学意义(P<0.01),血糖、HbA1c两组均无明显变化(P>0.05)。结论瑞舒伐他汀可显著降低ACS合并糖尿病患者LDL-C、血清hs-CRP水平,对血糖无明显影响,安全性好。  相似文献   
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n-Hexane is widely used in industry and its metabolite, 2,5-hexanedione (2,5-HD), has been implicated as a neural toxin in the developing fetus. Using the chick embryo model, we have previously revealed the neurotoxicity of 2,5-HD during development and established that high dose of 2,5-HD was embryo lethal. In view of the close linkage in biology for neurogenesis and angiogenesis, we speculated that it was most likely caused by cardiovascular dysplasia, therefore in this study, we investigated the effects of 2,5-HD on the development of the vasculature, which involves vasculogenesis and angiogenesis. Using gastrulating chick embryos as a model, we demonstrated that the hemangioblasts (precursor of hematopoietic and endothelial cells) migrated to the area opaca where they form the blood islands. However, this process was impaired when the embryos were treated with 2,5-HD, suggesting that 2,5-HD is capable of impairing vasculogenesis. To study the effect of 2,5-HD exposure on angiogenesis, we used the chick yolk-sac membrane (YSM) and chorioallantoic membrane (CAM) models. We found that, at low (0.02 M) concentration, 2,5-HD stimulated angiogenesis while at higher concentrations (>0.1 M) it inhibited this process. This biphasic response of angiogenesis to 2,5-HD exposure was found to be associated with altered expression of the VEGF-R, FGF-2 and angiogenin. Moreover, we also determined that 2,5-HD exposure increased the reactive oxygen species (ROS) production. In conclusion, 2,5-HD could induce dysplasia in the developing vasculature, which in turn could cause extravascular hemolysis and the embryos to die.  相似文献   
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Disruption of the pancreatic islet environment combined with the decrease in oxygen supply that occurs during isolation leads to poor islet survival. The aim of this study was to validate the benefit of using a plasma-based scaffold supplemented with perfluorodecalin to improve islet transplantation outcome.Rat islets were cultured in three conditions: i) control group, ii) plasma based-matrix (P-matrix), and iii) P-matrix supplemented with emulsified perfluorodecalin. After 24 h culture, matrix/cell contacts (Integrinβ1, p-FAK/FAK, p-Akt/Akt), survival (caspase 3, TUNEL, FDA/PI), function, and HIF-1α translocation were assessed. Afterwards, P-matrices were dissolved and the islets were intraportally transplanted. Graft function was monitored for 31 days with glycaemia and C-peptide follow up. Inflammation was assessed by histology (macrophage and granulocyte staining) and thrombin/anti-thrombin complex measurement.Islet survival correlated with an increase in integrin, FAK, and Akt activation in P-matrices and function was maintained. Perfluorodecalin supplementation decreased translocation of HIF-1α in the nucleus and post-transplantation islet structure was better preserved in P-matrices, but a quicker activation of IBMIR resulted in early loss of graft function.“Oxygenating” P-matrices provided a real benefit to islet survival and resistance in vivo. However, intraportal transplantation is not suitable for this kind of culture due to IBMIR; thus, alternative sites must be explored.  相似文献   
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目的 :比较股骨颈骨折全髋置换术后放置真空负压引流瓶,不同负压下术后失血量的差异。方法 :选取2013年1月1日至2013年12月30日采用生物型全髋关节置换术治疗的74例股骨颈骨折患者,分成高负压引流组和低负压引流组。高负压引流组34例,男10例,女24例;平均年龄(75.94±9.02)岁;术毕放置60 k Pa负压真空负压引流瓶。低负压引流组40例,男13例,女27例;平均年龄(74.93±8.90)岁;术毕放置30 k Pa负压真空负压引流瓶。对术后伤口引流量、血红蛋白改变值、根据身高体重和手术前后红细胞压积(Hct)计算的所有患者总失血量等进行观察,并做统计学分析进行比较。结果:两组患者术后切口均Ⅰ期愈合,无感染发生。术后第1天,高负压引流组血红蛋白改变值为(41.74±15.69)g/L,总失血量(1 217.73±459.50)ml,术后引流量(312.94±103.44)ml;低负压引流组血红蛋白改变值(34.90±12.90)g/L,总失血量(904.01±381.58)ml,术后引流量(129.25±44.25)ml,高负压引流组的数值均高于低负压引流组。术后3 d,高负压引流组血红蛋白改变值为(46.00±13.29)g/L,总失血量(1 304.72±421.75)ml;低负压引流组血红蛋白改变值为(43.87±11.39)g/L,总失血量(1 196.78±344.20)ml,两组差异无统计学意义。结论:股骨颈骨折生物型全髋关节置换术后放置引流时,根据患者术前血红蛋白、红细胞压积等情况选择负压引流压力大小,老年性股骨颈骨折选择低负压引流更为合适。  相似文献   
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主动脉瘤腔内修复(EVAR)术后可发生血红蛋白和(或)凝血功能的急性变化,并已经开始受到重视。但这种急性变化的病理机制以及对于EVAR术后的影响尚不明确。笔者对EVAR术后血红蛋白和凝血功能变化特点的研究进展进行综述。  相似文献   
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