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961.
1株诱变枯草杆菌溶栓酶性质研究的初探   总被引:1,自引:0,他引:1  
目的 对从1株诱变的枯草杆菌的发酵液中,通过分离纯化得到的一种活性较高的纤溶酶进行性质研究。方法 按胰酶活性测定法测其水解酪蛋白活性,用SDS-PAGE测定分子量,等电聚焦测定其等电点。采用硫酸酚法测定糖含量,并对其药理性质进行研究。结果 其水解酪蛋白活性为2.1U/mg,分子量为62kDa。等电点为8.5。含糖量为32%,并且发现该酶具有直接降解纤维蛋白的活性。结论 此纤溶酶具有较高的活性及药理价值。  相似文献   
962.
自由基损伤和β2糖蛋白1在自身免疫疾病中的作用   总被引:2,自引:0,他引:2  
目的 研究被自由基氧化修饰的β2糖蛋白1(β2GPl)在自身免疫疾病中自身抗体产生中的作用。方法 采用高氯酸沉淀,两步肝素连接的交联琼脂糖凝胶层析结合葡聚糖凝胶G—100分离纯化大鼠β2GP1;应用自由基氧化修饰大鼠β2GP1;氧化修饰的β2GP1(oxβ2GPl)、β2GPl分别加与不加心磷脂(CL)及CL免疫大鼠,ELISA方法检测免疫大鼠血清中抗β2GP1抗体和抗心磷脂抗体(ACA)。结果 两步亲和层析结合凝胶过滤层析有效地分离纯化了大鼠β2GPl,蛋白纯度达90.78%;通过碳基含量测定证实了自由基对β2GP1的氧化修饰;oxβ2GGP1加CL、β2GP1加CL、oxβ2GPl免疫组与空白对照组、实验对照组比较ACA水平有显著升高(P<0.001),oxβ2GP1加CL免疫组与β2GPl加CL免疫组比较ACA水平差异有显著性(P<0.05);oxβ2GP1免疫组与oxβ2GPl加CL免疫组比较ACA水平差异不显著(P>0.05);oxβ2GPl加CL、oxβ2GPl免疫组与对照组比较,抗oxβ2GP1抗体水平有显著升高(P<0.05)。结论 两步肝素连接的交联琼脂糖凝胶层析结合葡聚糖凝胶G—100能有效地分离纯化β2GPl;oxβ2GPl诱导了ACA和抗oxβ2GPl抗体的产生;β2GPl可能是自身免疫疾病发生过程重要的辅助因子或靶抗原,而自由基对β2GP1损伤可能是自身免疫疾病发病机制中的一个重要病理过程。  相似文献   
963.
首例中国可视化人体心脏三维重建及临床意义   总被引:5,自引:1,他引:4  
目的 对首例中国数字化可视人体的心脏进行三维重建,为心脏疾病的影像学诊断和外科手术提供三维解剖学依据。方法 将首例中国数字化可视人体心脏部分的薄层断面(层厚1.0mm)输入SGI工作站,经数据分割、对位重建、平滑处理和三维显示等步骤,完成对心脏结构的三维重建。结果 本研究完整地重建出了心脏结构,重建的结构能够以多结构、多彩色实体模型方式显示,可显示心脏内部各结构的空间位置和毗邻关系,可在三维空间伴置上绕任意轴旋转任意角度。结论 重建出的三维图像清晰地显示了心脏内部和整体的结构,实现了心脏的二维可视化。  相似文献   
964.
Objective To investigate the roles of somatostatin(SS)positive intemeurons in the development and compensation of temporal lobe epilepsy.Methods Piloearpine-induced epilepsy rat model was established.Immunohistochemistry method was used to detect number changes and axonal sprouting of SS positive intemeurons in different domains of the hippocampus at difierent time points.Degeneration of SS positive interneurons and their neurophils were detected by the double immunofluorescence staining with SS and Fluoro-Jade B(FJB)at 7 and 60 days after status epilepticus (SE).Results In the exoerimental rat group,the number of SS positive neurons decreased in each hippocampal domain,and it reached the lowest at 7 days post-SE(There were 11.1±3.3 in hilus,2.8±0.9 in CA1region and 1.8±0.7 in CA1region,t=13.519,9.644 and 8.808,all P<0.01).In chronic phase,the number of SS neurons gradually recovered,and exceeded the control group in CA1 area at 60 days post-SE(12.8±1.5 vs 8.8±1.3,t=-4.506,P<0.01),however,the number of SS neurons in the hilus(25.5±4.6)and CA1 area(4.8±0.8)remained significantly less than normal levels(t value were 4.691 and 3.953.both P<0.01).Increased SS positive fibers were found in the lacunosum-molecular (1m)layer and outer molecular layer of dentate gyrus after 30 days post-SE,and numerous SS positive fibers were seen threnghout the layers of area CA1 at 60 days post-SE.Double immunofluuorescence revealed that a few SS positive interneurons and fibers were also labeled by FJB in area CA1 at 7 days post-SE and in CA domain/hilus at 60 days post-SE.Conclusions SS intemeurons loss plays an important role in the development of temporal lobe epilepsy.The loss is partially caIlsed by the degeneration and death of neurons;SS positive neurophils increase within area CA1 in chronic phase may play a significant role in the generation and compensation of temporal lobe epilepsy.  相似文献   
965.
甲磺酸罗比卡因与盐酸罗比卡因用于硬膜外阻滞的效应比较   总被引:10,自引:0,他引:10  
目的 评价甲磺酸罗比卡因用于硬膜外阻滞的效应和安全性。方法 45例择期行下腹或下肢手术病人,随机分别接受用甲磺酸罗比卡因(8.94 mg/ml,观察组)或盐酸罗比卡因(7.5mg/ml,对照组)施行的硬膜外阻滞。观察两组在感觉阻滞、运动阻滞、镇痛和肌肉松弛方面的效果,同时观察用药前后肝肾功能变化。结果 观察组和对照组感觉阻滞平面达到T6以上的病例分别为84.3%和76%(P>0.05),Bromage≥3级的病例分别90%和92%(P>0.05)。两组感觉阻滞平面固定时间、Bromage达到最大级别时间、最大级别维持时间和运动阻滞维持时间均无显著性差异(P>0.05)。两组镇痛及肌松满意率无显著性差异。观察组术中2例发生低血压,2例发生心动过缓,而对照组仅1例发生低血压。两组术后24 h天冬氨酸氨基转移酶(AST)、天冬氨酸转氨酶(ALT)、尿素氮(BUN)和肌酐(Cr)均在正常范围。结论 甲磺酸罗比卡因与盐酸罗比卡因行硬膜外阻滞的效应基本相同,且无明显毒性。  相似文献   
966.
多站点综合性毕业考试的改革与实践   总被引:5,自引:0,他引:5  
我校改革临床医学专业毕业考试模式与方法,在临床实习过程中组织多站点综合性考试,采用闭卷笔试方法考核临床理论知识,占70%;采用实践操作与现场口试方法考核临床技能及相关知识,占20%;采用开卷笔试方法考核医疗文书书写,占10%。实践证明,此项改革能促进医学生端正实习态度,调动实习的积极性与主动性,引导医学生在实习中重视理论学习与临床实践的密切结合,促进临床教学质量的提高。  相似文献   
967.
OBJECTIVE: To study the value of neuronavigation in the transpetroal approach, and to provide anatomic data for the protection of the nerves in the facial nerve canal (FNC) during surgeries. METHODS: Simulated surgery through the transpetroal approach was performed on 16 sides of 8 adult cadaver heads with the assistance by neuronavigation. The anatomy of the facial nerve and the relationship of related structures were observed and the distances from the utmost external edge of the mastoid to different segments of the FNC were measured. RESULTS: Neuronavigation was successful with all the FNC, with the mean error of less than 0.9 mm. The FNC could be divided into 3 segments, the labyrinthine, the tympanic and the mastoid segments, stretching 3.6+/-1.2 mm, 11.2+/-2.5 mm and 16.1+/-3.6 mm respectively and with diameters of 1.2+/-0.3 mm, 1.4+/-0.1 mm and 1.7+/-0.2 mm, respectively. CONCLUSION: Neuronavigation may help protect the FNC during surgical procedures, and a thorough knowledge of the anatomic features of the FNC can be significant for preservation of the facial nerves.  相似文献   
968.
目的:调查分析邯郸市第四医院141名临床护士的工作压力情况,为寻找减轻压力措施及提高护理工作质量提供实验数据。方法:2004-02-06/2004-02-10对邯郸市第四医院141名护士采用自填式问卷进行调查,问卷内容分为引起护士压力的常见因素及压力程度两部分。引起压力常见因素包括:担心差错事故、生活规律改变、晋升问题、人际关系、工作任务繁重、工资收入、学习考试。压力程度:压力很大指护理人员自我感觉疲惫心慌,对日常工作和生活造成显著的影响;压力较大指自我感觉压力较大,对日常工作和生活有一定程度的影响;压力一般指自我感觉存在一定程度的压力,但主观上能够适应,对自己不是一种负担;没有压力指工作轻松愉快,主观感觉没有任何不适应。结果:①不同科室压力分布:内科系统45名中有8名认为压力很大或较大,外科系统62名中有34名认为压力很大或较大,急诊科15名中有13名认为自己的工作压力较大。与内科系统比较,外科系统、急诊科普遍认为工作压力较大(P<0.01或0.05)。②年龄、性别、职称、学历对压力分布的影响:年龄、性别、职称、学历对护士压力分布无明显影响(P>0.05)。③各种压力因素及所占比例分析:担心差错事故的发生位居首位,高达78.01%;其次为生活规律改变及晋升问题,分别为48.94%和47.52%。结论:临床护士压力分布是不平衡的,外科系统和急诊科的工作压力相对较大,担心差错事故发生是引起护士压力的主要因素。  相似文献   
969.
Bone marrow stromal cells (MSCs) increase vascular endothelial growth factor (VEGF) expression and promote angiogenesis after stroke. Angiopoietin-1 (Ang1) and its receptor Tie2 mediate vascular integrity and angiogenesis as does VEGF and its receptors. In this study, we tested whether MSC treatment of stroke increases Ang1/Tie2 expression, and whether Ang1/Tie2 with VEGF/ vascular endothelial growth factor receptor 2 (VEGFR2) (Flk1), in combination, induced by MSCs enhances angiogenesis and vascular integrity. Male Wistar rats were subjected to middle cerebral artery occlusion (MCAo) and treated with or without MSCs. Marrow stromal cell treatment significantly decreased blood-brain barrier (BBB) leakage and increased Ang1, Tie2, and occludin (a tight junction protein) expression in the ischemic border compared with MCAo control. To further test the mechanisms of MSC-induced angiogenesis and vascular stabilization, cocultures of MSCs with mouse brain endothelial cells (MBECs) or astrocytes were performed. Supernatant derived from MSCs cocultured with MBECs significantly increased MBEC expression of Ang1/Tie2 and Flk1 compared with MBEC alone. Marrow stromal cells cocultured with astrocytes also significantly increased astrocyte VEGF and Ang1/Tie2 expression compared with astrocyte culture alone. Conditioned media from MSCs alone, and media from cocultures of MSCs with astrocytes or MBECs, all significantly increased capillary tube-like formation of MBEC compared with control Dulbecco's modified Eagle's medium media. Inhibition of Flk1 and/or Ang1 significantly decreased MSC-induced MBEC tube formation. Knockdown of Tie2 expression in MBECs significantly inhibited MSC-induced tube formation. Our data indicate MSC treatment of stroke promotes angiogenesis and vascular stabilization, which is at least partially mediated by VEGF/Flk1 and Ang1/Tie2.  相似文献   
970.
Glial glutamate transporter-1 (GLT-1) plays an essential role in removing glutamate from the extracellular space and maintaining the glutamate below neurotoxic level in the brain. To explore whether GLT-1 plays a role in the acquisition of brain ischemic tolerance (BIT) induced by cerebral ischemic preconditioning (CIP), the present study was undertaken to observe in vivo changes in the expression of GLT-1 and glial fibrillary acidic protein (GFAP) in the CA1 hippocampus during the induction of BIT, and the effect of dihydrokainate (DHK), an inhibitor of GLT-1, on the acquisition of BIT in rats. Immunohistochemistry for GFAP showed that the processes of astrocytes were prolonged after a CIP 2 days before the lethal ischemic insult, which could protect pyramidal neurons in the CA1 hippocampus against delayed neuronal death induced normally by lethal ischemic insult. The prolonged processes extended into the area between the pyramidal neurons and tightly surrounded them. These changes made the pyramidal layer look like a 'shape grid'. Simultaneously, the prolonged and extended processes showed a great deal of GLT-1. Western blotting analysis showed significant upregulation of GLT-1 expression after the CIP, especially when it was administered 2 days before the subsequent lethal ischemic insult. Neuropathological evaluation by thionin staining showed that DHK dose-dependently blocked the protective role of CIP against delayed neuronal death induced normally by lethal brain ischemia. It might be concluded that the surrounding of pyramidal neurons by astrocytes and upregulation of GLT-1 induced by CIP played an important role in the acquisition of the BIT induced by CIP.  相似文献   
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