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101.
本文观察到腺苷脱氨酶抑制剂EHNA对离体灌流大鼠心脏氧反常性损伤有明显的作用,此外还发现在缺氧期(无氧灌流30分钟)EHNA也表现出明显的保护作用,心脏收缩幅度的降低和静息张力的升高均显著低于对照组。表明在缺氧期也可能有自由基的产生。 相似文献
102.
In order to research the states of dentine surface and dentine surface primed with coupling agent, we used microscope, transmission electron microscope (TEM) and solid fluorescence method. Observed under microscope, patterning of dentinal tubules and their poles was very explicit; through the view of interface between coupling agent adsorbed and human dentine powder by TEM, it was revealed that the coupling agent was adsorbed onto the dentine surface as if it "grew out" of the dentine surface; through examination of interface between the coupling agent adsorbed and dentine surface by fluorescence spectrum, which differed from that of the coupling agent or dentine surface, i.e., this fluorescence spectrum of interface changed obviously (red shift). This phenomenon indicated that there was a chemical reaction occurring between tooth surface and adsorbed coupling agent. Therefore we can conclude that the three examinations are necessary to provide the argument for establishment of chemical bonding mechanism between dentine and coupling agent. 相似文献
103.
为研究选择性胃肠道钙通道拮抗剂与肠道菌群调节剂对肠易激综合征(IBS)的疗效,从1998年1月至1999年10月对84例IBS患者分两组进行了观察。联合治疗组(联合组)采用钙通道拮抗剂匹维溴铵与微生态活菌制剂米雅-BM联合治疗,对照组单用匹维溴铵。联合组的腹痛及腹泻有效率分别为95.9%(47/49)和93.3%(28/30),明显高于对照组的81.2%(26/32)和69.6%(16/23)并均有显著性差异(P<0.05),但便秘及便秘腹泻交替等症状的疗效两组无明显差异。提示IBS腹泻型的部分患者可能确有肠道菌群失调,对这部分患者采用匹维溴铵加调节肠道群菌的药物治疗可取得更好的疗效。 相似文献
104.
膀胱移形细胞癌微血管密度与病理组织学分级和预后的关系 总被引:1,自引:0,他引:1
目的:探讨肿瘤血管形成及其密度与膀胱移行细胞癌生物学行为的关系。方法:应用免疫组织化学方法检测了67例膀胱移行细胞癌组织中FⅧ因子相关抗原的表达和肿瘤组织中微血管的长度密度(LV)和微血管截面数(QA)。结果:膀胱癌组织中微血管LV明显高于正常膀胱(P〈0.01)。但高分化膀胱癌微血管LV与正常膀胱无显著性差异(P〉0.05)。膀胱癌分化越差,微血管LV越高;有肌层浸润组微血管LV明显高于无肌层浸 相似文献
105.
糖尿病患者血清中IL-4、TNF-a的检测及分析 总被引:1,自引:0,他引:1
目的 探讨白介素4(IL-4)、肿瘤坏死因子(TNF-a)水平与糖尿病关系。方法 采用ELISA法测定54例糖尿病患者及40例健康人血清IL-4、TNF-a含量。结果 糖尿病患者IL-4平均含量明显低于健康人(P〈0.05),且与血糖一负相关(r=-0.347,P〈0.05)。TNF-a含量略高于对照组,但无统计学意义。结论 糖尿病患者内存在细胞免疫功功能紊乱,自身免疫功能调节失衡影响糖尿病的发生 相似文献
106.
RuthMabel Boytz Mikołaj Słabicki Sita Ramaswamy J. J. Patten Charles Zou Chengcheng Meng Brett L. Hurst Jinhua Wang Radosław P. Nowak Priscilla L. Yang Martin Sattler Richard M. Stone James D. Griffin Nathanael S. Gray Suryaram Gummuluru Robert A. Davey Ellen Weisberg 《Journal of medical virology》2023,95(1):e28157
Coronavirus disease 2019 (COVID-19) remains a major public health concern, and vaccine unavailability, hesitancy, or failure underscore the need for discovery of efficacious antiviral drug therapies. Numerous approved drugs target protein kinases associated with viral life cycle and symptoms of infection. Repurposing of kinase inhibitors is appealing as they have been vetted for safety and are more accessible for COVID-19 treatment. However, an understanding of drug mechanism is needed to improve our understanding of the factors involved in pathogenesis. We tested the in vitro activity of three kinase inhibitors against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), including inhibitors of AXL kinase, a host cell factor that contributes to successful SARS-CoV-2 infection. Using multiple cell-based assays and approaches, gilteritinib, nintedanib, and imatinib were thoroughly evaluated for activity against SARS-CoV-2 variants. Each drug exhibited antiviral activity, but with stark differences in potency, suggesting differences in host dependency for kinase targets. Importantly, for gilteritinib, the amount of compound needed to achieve 90% infection inhibition, at least in part involving blockade of spike protein-mediated viral entry and at concentrations not inducing phospholipidosis (PLD), approached a clinically achievable concentration. Knockout of AXL, a target of gilteritinib and nintedanib, impaired SARS-CoV-2 variant infectivity, supporting a role for AXL in SARS-CoV-2 infection and supporting further investigation of drug-mediated AXL inhibition as a COVID-19 treatment. This study supports further evaluation of AXL-targeting kinase inhibitors as potential antiviral agents and treatments for COVID-19. Additional mechanistic studies are needed to determine underlying differences in virus response. 相似文献
107.
Fan Wu Yue Yuan Yanjun Li Di Yin Bing Lang Yangguo Zhao Xueying Fan Huachun Zou Chunhuan Zhang Xiangyue Zeng Caijun Sun 《Journal of medical virology》2023,95(1):e28227
Compared with the nucleic acid amplification test (NATT), the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) rapid antigen self-testing (RAST) has advantages in speed and convenience. However, little is known about people's acceptance and influencing factors for SARS-CoV-2 RAST. A cross-sectional study was conducted from April 21 to 30, 2022 in China. The χ2 test and multivariate logistic regressions were used to identify the influencing factors. The structural equation model was used to test the extended protective motivation theory (PMT) model hypotheses. Among the total of 5107 participants, 62.5% were willing to accept the SARS-CoV-2 RAST. There were significant differences in acceptance among different residences (p < 0.001), educational level (p < 0.001), occupation (p < 0.001), monthly income (p < 0.001), travel frequency (p < 0.05), and feelings about NATT (p < 0.001). Response efficacy (β = 0.05; p = 0.025) and self-efficacy (β = 0.84; p < 0.001) had a positive effect, while response cost showed a negative effect (β = −0.07; p < 0.001). The public's major concerns about SARS-CoV-2 RAST are its reliability, testing method, price, and authority. Overall, a moderate intention to use SARS-CoV-2 RAST was found among the Chinese population. The extended PMT can be used for the prediction of intention to accept the RAST. We need to take measures to increase people's acceptance of SARS-CoV-2 RAST. 相似文献
108.
109.
目的 探讨获取母血中纯化胎儿细胞的有效方法。方法 对 6 0名孕龄 7~ 40周、年龄 2 1~ 30岁的孕妇外周血进行不连续密度梯度离心 ,将分离后的细胞进行制片 ,显微镜下行显微操作分离胎儿有核红细胞 ,进行 Y染色体特异性DYZ1基因的聚合酶链反应 (PCR)。结果 (1)早孕期母血中胎儿 NRBC检出率为 2 0 % ,中孕期母血中胎儿 NRBC检出率为 71.4% ,晚孕期母血中胎儿 NRBC检出率为 6 .6 5 % ,三者之间有显著性差异 (P <0 .0 5 ) ;(2 )用显微操作技术获得的胎儿细胞数量已满足 PCR扩增所需的模板量 ,对胎儿性别进行预测 ,男胎符合率为 11/ 13(84.6 % ) ,性别符合率为 2 6 / 2 8(92 .9% )。结论 不连续密度梯度离心合并显微操作技术对于无创性早期产前基因诊断意义重大。 相似文献
110.
目的用毛细管电泳中的胶束动电法直接测定血清尿酸浓度。方法以SDS作为电泳缓冲液中和胶束相,采用非涂渍毛细管21cm×50μm(i.d.),检测波长235nm,以外标法定量。结果尿酸测定的线性范围为46.5~1500μmol/L,最低检测限为20.31μmol/L:本法的日内和日间变异系数均小于4.5%;平均回收率为101.45%。内生性化合物和临床某些常用药物对此方法无干扰。结论该法线性范围宽,简单、快速,可应用于临床样品检测。 相似文献