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91.
BACKGROUND: Inhibitory signals, i.e. neurite growth inhibitors (NGIs), presenting on central nervous system (CNS) myelin have been shown to play a crucial role in inhibiting lesioned axonal sprouting and leading to less functional recovery. Vaccines targeting NGIs may provide multifactorial protection against brain insults by overcoming the inhibitory effects of these NGIs and boosting the body's immune repair mechanisms. OBJECTIVE: To evaluate the effect of poststroke DNA immunization against NGIs on the rehabilitation for sensorimotor function of rat models of local cerebral ischemia. DESIGN: Completely randomized grouping design, and controlled experiment. SETTING: Brain Injury Research Laboratory, Department of Neurosurgery, National Neuroscience Institute, Singapore. MATERIALS: Sixty adult male Sprague-Dawley rats ranging in age from 45 to 120 days and in weight from 180 to 250 grams were provided by Animal Center of Department of Anatomy, Faculty of Medicine, National University of Singapore. pcDNA3.1(+)-neurite growth inhibitors (pcDNA-NGIs) a gift was provided by Dr. Xiao from Department of Clinical Research, Singapore General Hospital, Singapore. METHODS: The experiment was carried out at Brain Injury Research Laboratory, Department of Neurosurgery, National Neuroscience Institute, Singapore from August 2003 to April 2005. (1)The involved rats were randomized into 3 groups: pcDNA-NGIs group (group A), pcDNA3.1 (+) group (group B) and model group (group C), with 20 rats in each group. Left focal cerebral ischemia (FCI) was permanently induced through middle cerebral artery occlusion (MCAO) with the assistance of an operating microscope. Successful MCAO was determined by a 20% decrease to baseline in the ipsilateral cerebral blood flow. 100 μg of pcDNA-NGIs eluted in phosphate-buffered saline (PBS) was intramuscularly injected into the tibial muscle once a week after MCAO for 6 weeks in group A. As control, pcDNA3.1 (+) was also administrated in the same way in group B and nothing was administrated in group C. (2) The modified neurological severity score (mNSS), a composite of motor, sensory, reflex and balance tests, was used to test the sensorimotor deficit. The mNSS was graded on a scale of 0 - 18, i.e. normal score was 0, maximal deficit score was 18, and 1 point was warded for the inability to perform the tasks or the lack of a tested reflex. (3) The newly generated axons of corticorubral projection were traced by stereotaxic guided injection of 100 g/L biotinylated dextran amine. Rats were sacrificed two weeks after tracing, and cryostat coronal sections of midbrains (30μm) were reacted to BDA according to the manufacturer's instruction by the free-floating method. Images were captured on a DM RXA2 LEICA Microscope with a Spot Digital Camera system (Germany), and the numbers of labeled axons on the denervated side in four standard coronal sections including the red nucleus were manually quantified. MAIN OUTCOME MEASURES: (1) The number of newly generated axons of corticorubral projection. (2)The improvement in sensorimotor deficit. RESULTS: All the involved 60 rats entered the stage of final analysis. (1) The number of newly generated axons of corticorubral projection of rats: Only ipsilateral axons of CRP were noted with little evidence of fibers crossing to the contralateral red nucleus in rats of groups B and C. More BDA-positive fibers crossing the midline and terminating in the contralateral red nucleus in appropriate target areas mirroring the non-differentiated red nucleus were found in rats of group A. Quantitative analysis showed that BDA-labeled axons in the denervated side of rats in group A were more than those in group B (P 〈 0.05). (2) Improvement in sensorimotor deficit of rats: At 2 weeks after immunization, significant improvement in sensorimotor deficit was found in rats of group A. There were significant differences of improvement in sensorimotor deficit of rats between group A and group B or group C at 12 and 14 weeks after immunization (P 〈 0.05). CONCLUSION: (1) Poststroke DNA immunization against NGIs leads to increased sensorimotor recovery following FCI and compensatory newly growth of axons from corticorubral projection.  相似文献   
92.
探讨人的增强子结合蛋白(C/EBP)相关基因。方法以大鼠C/EBPcDNA为探针,筛选人胎盘cDNA文库。结果得到一个含有1975碱基命名为HP8的cDNA克隆,其中1~604位碱基属编码区。经基因数据库查对未发现同源基因。该基因编码的蛋白C-末端含有亮氨酸拉链结构(leucine zipper struceure)和C/EBP功能区(C-末端60个氨基酸)同源性高达97%,而上游编码区则与C/EBP及其已知家族同源性很低,表明该基因属C/EBP基因家族新成员。基因组Southern杂交证实该基因为单拷贝基因。在14种胎儿组织中显示小肠、皮肤高表达,肾上腺中度表达,肝、肺、肾、甲状腺、胆囊低表达。在3例正常成人肝组织中仅1例低表达,而在5对肝癌及癌旁肝组织中显示2例癌组织及1例癌旁组织高表达。结论以上结果提示该基因可能与细胞增殖有关。  相似文献   
93.
为开展脐门静脉造影的介入放射学,弥补肝动脉化疗的不足,探讨肝脏内恶性肿瘤化疗的新途径。本文对8例男性肝脏左叶占位性病变患者作脐静脉穿刺造影测得肝圆韧带内脐静脉自肝门静脉左支囊都至腹壁脐切迹全长为19.4±4.3 cm。讨论了脐门静脉造影的优点及其临床意义。  相似文献   
94.
95.
面肌痉挛显微血管减压术的诱发肌电图监测和评估   总被引:1,自引:0,他引:1  
目的:探讨面神经诱发肌电图在显微血管减压(MVD)术中、术后对面肌痉挛治疗效果的监测和评估。方法:对26例典型面肌痉挛病人、探讨在MVD术前、术中、术后,经皮刺激痉挛侧(手术侧)面神经下颌缘支,记录诱发同侧眼轮匝肌肌电位(MD-OC反应)变化,并以正常侧作对照检查。结果:26例术前均记录到痉挛侧MD-OC反应,在术中操作不同阶段,21例均见MD-OC反应消失。术后1周~3个月随访复查21例中,12例痉挛完全消失,MD-OC反应不复存在,9例症状明显或部分减轻,但有4例再记录到MD-OC反应。另5例术中,术后均记录到MD-OC反应,症状未有改善。结论:面神经诱发肌电图运用于MVD术中监测和预后判断,可改善和提高面肌痉挛的治愈率。  相似文献   
96.
97.
正常国人肺静脉血流多普勒频谱分析   总被引:23,自引:2,他引:21  
运用彩色多普勒超声观察了107例正常国人的肺静脉血流(PVF)。结果:正负四相型(SIS2DA),占37%;正负三相型(SDA)占45%,正向两相型(SD)占18%。呼吸,性别不显著影响其表现,但心率、心律及取样容积位置均影响之。94%(101/107)正常者的SF>50%,表明正常国人前向性PVF主要是收缩期占主型,增龄使这一特征更明显。98%(105/107)正常者PVF的Ap<40cm/s,且其不受年龄影响。结论:正常国人PVF超声表现的多形性间有本质上的同一性,正确认识之有助于指导辨别病理性PVF频谱  相似文献   
98.
云南省卫生资源配置标准的弹性系数研究   总被引:2,自引:1,他引:1  
目的 在进行云南省区域分类基础上制定云南省区域卫生资源配置标准标志值后 ,根据云南省各个地区的特点增加不同弹性系数。方法 采用流行病学研究方法 ,收集和分析云南省不同地州市 1990~ 1999年有关人口、社会经济状况及卫生经费的投入、居民健康状况、居民文化、生活水平、少数民族状况、旅游地区、边境线长短及贫困状况等资料。结果 研究结果表明曲靖地区、玉溪市、保山地区增加弹性系数最少 ,分别为 0 67%、 1 5 8%和1 68% ,怒江州、迪庆州和西双版纳州增加弹性系数最多 ,分别为 11 15 %、 10 2 5 %和 9 84 %。其它地区的弹性系数分别为昆明市 5 88% ,昭通地区 2 3 1% ,楚雄州 2 3 0 % ,红河州 7 0 3 % ,文山州 5 5 3 % ,思茅地区 7 4 3 % ,大理州4 94 % ,德宏州 6 78% ,丽江地区 4 3 5 % ,临沧地区 6 13 %。结论 云南省区域卫生配置标准的弹性系数研究为云南省卫生资源区域分类配置标准提供了科学依据 ,不同弹性系数体现了云南省不同地区的卫生资源区域分类配置标准的公平性、合理性及实用性  相似文献   
99.
本文对精神分裂症患者用氯丙嗪治疗前后PAg(T)功能进行观察及BPRS评定,发现精分症患者PAg(T)功能明显高于对照组,用氯丙嗪治疗1个月后,BPRS评定分值下降,患者临床症状消除,而PAg(T)第一时相无变化,第二时相明显升高,说明氯丙嗪聚药物可促发血小板释放内源性致聚物质,同时也说明患者PAg(T)异常不仅仅是情绪应激所致,更重要的是血小板生理功能异常。  相似文献   
100.
BACKGROUND:Signal regulatory protein alpha1(Sirpα1) is a member of Sirps families containing four immunoreceptor tyrosine-based inhibitory motifs(ITIMs) domains in the cytoplasm of and an activated substrate of receptor tyrosine kinase(RTK),that negatively regulates the RTK-dependent cell proliferating signal transduction pathway.Previously we found that Sirpα1 was closely associated with the occurrence and development of hepatocellular carcinoma(HCC)as well as liver regeneration.Since it is unclear about the regulatory mechanisms,we established the cell line transfected Sirpα1 gene and preliminarily clarified the mechanisms by which Sirpα1 negatively regulates the carcinogenesis and development of HCC. METHODS:Liver cancer Sk-Hep1 cell was respectively transfected with plasmids of pLXSN,pLXSN-Sirpα1 and pLXSN-Sirpα1Δ4Y 2 ,screened with the drug of G418(1200 μg/ml),and various transfected Sk-Hep1 cell lines were obtained.The protein expressions of P65,P50,IκBα,cyclin D1 and Fas in various Sk-Hep1 cell lines were determined by Western blotting,and P65 and P50 were localized by the immunofluorescence technique. RESULTS:Sirpα1 could significantly upregulate the protein expression of IκBα(vs.other cell lines,P<0.05) in the Sk-Hep1 cell,and downregulate the protein expressions of P65,P50 and cyclin D1(vs.other cell lines, P<0.05)in the Sk-Hep1 cell.P65 protein expression was mainly localized in the cytoplasm in the pLXSN Sk-Hep1 cell,and in the nucleus of the Sk-Hep1 cell with mutantSirpα1Δ4Y 2 ,but in nucleus of the Sk-Hep1 cell with wild Sirpα1.P50 protein expression was localized in the cytoplasm and nucleus of the pLXSN Sk-Hep1 cell,but in the nucleus of the Sk-Hep1 cell with wild Sirpα1 and mutant Sirpα1Δ4Y 2 plasmid. CONCLUSIONS:Sirpα1 might negatively regulate and control the abnormal proliferation of liver cancer cells by influencing the protein content and localization of nuclear factor-kappa B,then influence the expression of cyclins such as cyclin D1 in the signal transduction pathway.It may be one of the important mechanisms by which Sirpα1 negatively regulates the carcinogenesis and development of HCC.  相似文献   
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