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31.
Cell culture-based transdominant genetic techniques provide new methods for discovering peptide/RNA modulators of cellular pathways. We applied this technology to isolate a peptide inhibitor of human rhinovirus. A green fluorescent protein (GFP)-scaffolded library of cDNA fragments was expressed in HeLa cells from a retroviral vector and screened for inhibitors of rhinovirus-mediated cell killing. A DNA clone, I421, increased cell survival in an HRV14 challenge assay from less than 0.5% to greater than 60%. It encodes a 53-amino-acid C-terminal extension of the GFP scaffold. Particular subclones of Hela cells expressing I421 (exemplified by I421dp3) show a delay in virus production and a 50-fold decrease in viral RNA levels at 6-8 h postinfection. HRV2, HRV14, and HRV16 show a dramatic decrease in plaque-forming ability on I421dp3 while Coxsackievirus B3 showed a small reduction. Levels of ICAM-1, the receptor for the main rhinovirus serotype, are not altered in I421dp3.  相似文献   
32.
Morphological characteristics of cultured olfactory bulb cells   总被引:1,自引:0,他引:1  
Cultured olfactory bulb cells from embryonic mice had ultrastructural characteristics similar to those of many cell types in the intact adult mouse olfactory bulb. Identified cultured cells included mitral/tufted cells, granule cells, short-axon cells, and fibrous and protoplasmic astrocytes. Cultured neurons were found as individual cells, clusters or aggregates. Clusters consisted of a loose array of neurons that appeared to be densely interconnected by neurites. However, few neurites or fascicles emanated from clusters to adjoining areas. Aggregates consisted of many small, usually rounded, neurons piled on top of one larger neuron, or on more than one, with typically many neurites and fascicles projecting to adjacent aggregates, clusters or individual neurons. Neurites of cultured olfactory bulb cells were well developed, and some were several millimeters long. Synapses were very prominent in these cultures, especially in aggregates, clusters, and fascicles. Electron-lucent, dense-core, and coated vesicles were present. Polarity, shape, and length of the long axis (size) of 815 cultured neurons, identified by positive anti-microtubule-associated protein 2 staining, were documented. Cultured neurons varied in size from 9 to 27 m, with an average size of 16 m. Elliptical bipolar (35%), triangular multipolar (21%), and round unipolar (15%) were the most common polarity/shape combinations found in culture. Multipolar, triangular, triangular multipolar, and elliptical bipolar cells increased in size with increasing age of culture. The relative proportions of triangular, multipolar, elliptical multipolar, and triangular multipolar cells decreased, whereas the relative proportions of round, unipolar, and round unipolar cells increased with increasing age of culture. These changes in population subtypes and cell size may indicate continued differentiation and maturation of cultured neurons.  相似文献   
33.
RNAi抑制XJ-160病毒复制的研究   总被引:2,自引:0,他引:2  
目的通过建立RNA干扰(RNA interference,RNAi)抑制XJ-160病毒复制的模型,在序列特异性、位置效应和量效关系等方面,探讨RNAi对XJ-160病毒复制的影响,为进一步研究RNAi的抗病毒作用和机制奠定基础。方法按照siRNA(short interferencing RNA)的设计要求合成XJ-160病毒特异siRNA,脂质体法转染BHK-21细胞后感染XJ-160病毒,通过测定病毒滴度、蛋白表达量及XJ-160病毒:RNA合成研究siRNA对XJ-160病毒复制的抑制。结果成功建立了RNAi抑制XJ-160病毒复制的模型,探讨了RNAi抑制该病毒复制作用的特点。结论外源导入的siRNA能够抑制XJ-160病毒的复制,并且这种抑制作用具有明显的序列特异性、位置效应和存在量效关系等特点;siRNA是通过降解病毒RNA实现抑制病毒复制作用的。  相似文献   
34.
The intent of the present study was to use chemical or electrical stimulation of cerebellar afferents to determine how different stimulation paradigms affect the pattern of activation of different populations of neurons in the cerebellar cortex. Specifically, we analyzed immediate changes in neuronal activity, identified neurons affected by different stimulation paradigms, and determined the time course over which neuronal activity is altered. In the present study, we used either systemic (harmaline) or electrical stimulation of the inferior cerebellar peduncle (10 and 40 Hz) to alter the firing rate of climbing and mossy fiber afferents to the rat cerebellum and an antibody made against the proto-oncogene, c-fos, as a marker to identify activated neurons and glia. In control animals, only a few scattered granule cells express nuclear Fos-like immunoreactivity. Although no other cells show Fos-like immunoreactivity in their nuclei, Purkinje cells express Fos-like immunoreactivity within their somatic and dendritic cytoplasm in control animals. Within 15 min of chemical or electrical stimulation, numerous granule and glial cells express Fos-like immunoreactivity in their nuclei. Cells in the molecular layer express Fos-like immunoreactivity following harmaline stimulation in a time and lobule specific manner; they do not appear to be activated in the electrical stimulation paradigm. Following harmaline injections, there is an initial loss of Fos-like immunoreactivity in the cytoplasm of Purkinje cells; 90 min later, nuclear staining is observed in a few scattered Purkinje cells. Following electrical stimulation, the cytoplasmic staining in Purkinje cells is enhanced; it is never present in the nucleus. Data derived from this study reveal cell-specific temporal and spatial patterns of c-Fos activation that is unique to each paradigm. Further, it reveals the presence of an activity dependent protein in the cytoplasm of Purkinje cell somata and dendrites.  相似文献   
35.
Minimalresidualleukemia(MRL)istheoriginofleukemiarelapse,thetreatmentofMRListhekey problemin preventingleukemiarelapseandprolongingtheillness freesurvivalofleukemiapatients.TCMholdsthatthemanifestationofMRLconsistedoftwocharacteristics:the Evilelimina…  相似文献   
36.
运用止泻颗粒剂与思密达作对照治疗小儿消化不良性肠炎,治疗组136例,对照组80例,2组总有效率分别为95.5%,37.5%,疗效比较具有显著性差异,P<0.01。  相似文献   
37.
目的 探讨化滞柔肝颗粒治疗非酒精性脂肪肝(nonalcoholic fatty liver disease,NAFLD)的作用机制。方法 高脂饮食饲养8周构建大鼠NAFLD模型,化滞柔肝颗粒ig给药4周。半自动生化分析仪测定大鼠血脂相关指标;油红O染色观察肝脏组织病理变化;Illumina Miseq测序平台对V3~V4可变区进行扩增和测序,超高效液相色谱串联质谱(UPLCMS/MS)开展血浆代谢组学研究,并结合Spearman进行肠道菌群与代谢组学之间的关联分析。结果 与模型组相比,化滞柔肝颗粒中、高剂量组可显著降低大鼠体质量(P<0.05、0.01)和血清总胆固醇(totalcholesterol,TC)、三酰甘油(triacylglycerol,TG)水平(P<0.01),升高高密度脂蛋白(high-density lipoprotein cholesterol,HDL-C)水平(P<0.05、0.01)。此外,化滞柔肝颗粒高剂量组还可显著降低大鼠低密度脂蛋白(low-density lipoprotein cholesterol,LDL-C)水平(P<0...  相似文献   
38.
目的 分析2010-2019年凉山彝族自治州布拖县抗病毒治疗HIV/AIDS的死亡影响因素,为今后制定可持续的抗病毒治疗策略提供参考依据。方法 采用病例对照研究方法,收集2010-2019年布拖县接受抗病毒治疗HIV/AIDS与死亡者基本和随访信息,按病例数2倍抽样组成对照组,采用logistic回归模型分析其死亡的影响因素。结果 研究对象为抗病毒治疗的HIV/AIDS 3 355例,死亡组1 179例,对照组共2 176例。其中,30~49岁占81.34%,男性占69.09%,彝族占99.55%,已婚或同居占91.12%,初中及以下文化程度占95.77%,农民占88.41%。多因素logistic回归分析结果显示,研究对象的死亡风险因素中,年龄≥50岁是18~29岁的5.08倍(95%CI:3.05~8.48)、女性是男性的0.70倍(95%CI:0.52~0.94)、注射吸毒传播途径是异性性传播途径的1.43倍(95%CI:1.06~1.91)、治疗前CD4+T淋巴细胞计数(CD4)≥350个/μl是CD4<200个/μl的0.38倍(95%CI:0.30~0.48)、最近1次使用含洛匹那韦/利托那韦(LPV/r)抗病毒治疗方案是司他夫定(d4T)+拉米夫定(3TC)+奈韦拉平(NVP)/依非韦伦(EFV)方案的0.04倍(95%CI:0.01~0.18)、耐药是不耐药的3.40倍(95%CI:2.13~5.42),无病毒载量结果且未做耐药检测是不耐药的12.98倍(95%CI:10.28~16.40)。结论 年龄、性别、传播途径、治疗前CD4、最近1次抗病毒治疗方案、抗病毒治疗后耐药检测情况是布拖县接受抗病毒治疗HIV/AIDS的死亡影响因素。应扩大病毒载量和耐药检测覆盖面,科学更换抗病毒治疗方案,开展依从性教育和医务人员培训,降低抗病毒治疗HIV/AIDS死亡率。  相似文献   
39.
袁丹  张燕  李一平  李玲  周玚  苏玲  叶黎  杨洪  梁姝 《现代预防医学》2021,(21):3967-3973
目的 分析四川省接受艾滋病抗病毒治疗6~12个月病毒学失败患者的耐药影响因素和耐药特征。方法 对2016—2019年接受治疗6~12个月且病毒学失败患者进行HIV-1基因型耐药检测,采用统计学logistic回归和卡方检验分析病毒学失败患者耐药发生的影响因素,以及不同地区和亚型毒株间耐药突变特征。结果 3626例患者符合调查标准,成功获得序列2915例(80.39%),其中1246(42.74%)例耐药,多因素logistic回归分析发现,注射吸毒者的耐药突变是异性性传播患者的1.90倍;艾滋病的耐药突变是HIV感染者的1.75倍;基线CD4+T淋巴细胞计数≥350个/μl和200~349个/μl的耐药突变是CD4+T淋巴细胞计数<200个μl的0.76和0.64倍;初始治疗方案含洛匹那韦/利托那韦(LPV/r)的二线治疗方案的耐药突变是是含齐多夫定的0.37倍;感染CRF01_AE亚型毒株的耐药突变是感染CRF07_BC亚型毒株的1.34倍。成都平原、川东北、川西北、川南和攀西地区耐药率分别为45.41%、37.47%、54.84%、43.38和34.34%,卡方检验有统计学意义(P<0.05);主要流行亚型CRF07_BC、CRF01_E、CRF08_BC和CRF85_BC耐药率分别为39.60%、48.55%、34.17%和44.27%,卡方检验有统计学意义(P<0.05)。结论 四川治疗6~12个月艾滋病患者病毒学失败的耐药率较高,耐药突变状况复杂多样,感染途径、基线CD4+T淋巴细胞计数、病程、感染毒株亚型、初始治疗方案是治疗6~12个月病毒学失败患者发生耐药的影响因素,且各地区耐药发生和各亚型耐药突变特征不同。  相似文献   
40.
The dentate gyrus is one of the few areas of the mammalian brain where new neurons are continuously produced in adulthood. Certain insults such as epileptic seizures and ischemia are known to enhance the rate of neuronal production. We analyzed this phenomenon using the temporary occlusion of the two carotid arteries combined with arterial hypotension as a method to induce ischemia in rats. We measured the rate of cell production and their state of differentiation with a mitotic indicator, bromodeoxyuridine (BrdU), in combination with the immunohistochemical detection of neuronal markers. One week after the ischemic episode, the cell production in dentate gyrus was increased two- to threefold more than the basal level seen in control animals. Two weeks after ischemia, over 60% of these cells became young neurons as determined by colabeling with BrdU and a cytoplasmic protein (CRMP-4) involved in axonal guidance during development. Five weeks after the ischemia, over 60% of new neurons expressed calbindin, a calcium-binding protein normally expressed in mature granule neurons. In addition to more cells being generated, a greater proportion of all new cells remained in the differentiated but not fully mature state during the 2- to 5-week period after ischemia. The maturation rate of neurons as determined by the calbindin labeling and by the rate of migration from a proliferative zone into the granule cell layer was not changed when examined 5 weeks after ischemia. The results support the hypothesis that survival of dentate gyrus after ischemia is linked with enhanced neurogenesis. Additional physiological stimulation after ischemia may be exploited to stimulate maturation of new neurons and to offer new therapeutic strategies for promoting recovery of neuronal circuitry in the injured brain.  相似文献   
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