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91.
New findings from neuroscience, genetics, and experimental psychology have emerged that provide alternative explanations of many negative symptoms. We review the continuing limitations in treatment and discuss possible sources of heterogeneity among negative symptoms. We also anticipate conceptual uncertainties that may arise with forthcoming treatment developments.  相似文献   
92.
Background: The Strengths and Difficulties Questionnaire (SDQ) is designed to measure psychological adjustment in children and adolescents. Psychometric evaluations of the instrument have shown satisfactory convergent and discriminant validity, while factor analysis studies have shown mixed results across countries. In the present study, the construct validity of the five‐factor SDQ is evaluated in a large community sample of Norwegian pre‐, early, and late adolescents. Methods: The sample consisted of 26,269 children and adolescents (10–19 years) with valid answers on all 25 items of the SDQ self‐report. Complete parent/proxy data of respective pre‐adolescent children was available for 6,645 cases. A Lisrel approach to Confirmatory Factor Analysis (CFA) was used to evaluate the five‐factor model and the presence of a positive construal factor. In the sample of pre‐adolescents and their parents/proxies, convergent and discriminant validity was evaluated by a CFA approach to multitrait‐multimethods (MTMM). Results: Fit statistics for the hypothesized five‐factor model were satisfactory, but introducing correlated error terms for some of the items led to significant model improvement in all age groups. All factor loadings were higher than .30, except for item 11 (good friend). The loadings differed across age groups and differed markedly between the parent/proxy and self‐report measures. The MTMM showed that the source of ratings made a difference on the validity of all subscale ratings, with self‐reports discriminating more on ratings of emotional and peer problems, and parents/proxies discriminating more on hyperactivity symptoms. A positive construal factor was identified but had a modest effect compared with the original five traits. Results suggested an unclear construct and meaning of the Prosocial behaviour subscale. Conclusion: The results of the present study indicated support for the proposed five‐factor structure of the SDQ ( Goodman, 2001 ) across a wide age range (10–19years), including older adolescents and different informants. However, some improvements should be considered to improve internal reliability and conceptual clarity.  相似文献   
93.
我国医院信息主管的窘境与出路   总被引:5,自引:2,他引:5  
我国医院信息化建设还属初级阶段,一些医院信息机构尚处在"边缘化"状态;医院CIO并不能进入医院管理核心层,无法真正参与战略规划和全面推动医院信息化进程;医院CIO未能实现应有的权力价值,并缺乏清晰的升迁路径,进而导致心态失衡.我国医院CIO生存环境的改善和事业的发展,一方面取决于医院信息化建设的水平、医院CIO体制的建立、医学信息学教育与培训;另一方面更取决于医院信息管理者在推动医院信息化进程中做出的贡献.  相似文献   
94.
Until now most of the research on social support has concentrated on general support in relationship to the whole group of people around each individual. In contrast, only a few studies have dealt with individual-specific support (i.e. social support from a particular individual relationship). The Quality of Relationship Inventory (QRI) is a recently developed questionnaire to measure individual-specific social support. We developed the Japanese version by means of back translation and ascertained its reliability and validity among the Japanese women who had had two recurrent spontaneous abortions without known organic etiologies. Factor analysis revealed that the Japanese QRI had a two-factor structure, representing supportive and conflictual aspects of a particular relationship (named Factor-S and Factor-C, respectively). Each factor showed satisfactory reliability with Cronbach's alphas of 0.95 and 0.89. When the QRI scores were compared with the scales from the Social Support Questionnaire, a measure of general social support, the Factor-C of the former with respect to the mother correlated negatively with the Social Support Satisfaction of the latter (r = - 0.40; 95% confidence interval (CI) - 0.64 to - 0.09). Childhood experiences with parents also showed expected correlations with the QRI: care received from the parent before age 16 years strongly predicted Factor-S with that parent (r = 0.50, 95% CI 0.21-0.71 in the case of the mother; r = 0.54, 95% CI 0.27-0.73 in the case of the father). Although we still need to examine the Japanese QRI with different populations, it appears to be a promising measure of individual-specific relationship for the Japanese population.  相似文献   
95.
We recently discovered human p51 , a new gene structurally and functionally related to human p53. This gene encodes two major splicing variants, p51A and p51B, which differ in their carboxyl-terminal structure. However, p51A shows strong transactivation potential, while p51B has only weak potential. To clarify the reason for this difference, we made chimeric gene constructs expressing fusion proteins of p53-p51A and p53-p51B, having an N-terminus of p53 and a C-terminus of p51A or p51B, respectively. In a BAX promoter-luciferase assay using p53-deficient SAOS-2 cells, they exhibited up to 30-fold stronger transactivation potential than p53 and p51A themselves, suggesting that the C-terminus of p51B does not simply serve as a repressor. We obtained similar results with p21WAF1 promoter-reporter plasmids. These chimeras will be valuable tools for gene therapy.  相似文献   
96.
人抗菌肽HBD-2的原核表达及其多克隆抗体的制备与鉴定   总被引:1,自引:0,他引:1  
制备人β-防御素2(HBD-2)多克隆抗体,以用于HBD-2蛋白水平表达的检测。提取人肠腺上皮细胞株Caco-2总RNA,设计引物,应用RT-PCR从其总RNA中扩增HBD-2成熟肽cDNA片段,以pGEX-1λT为载体,构建原核表达质粒pGEX-1λT-HBD-2。大肠杆菌裂解物经亲合层析纯化后获得分子量约30kDa的融合蛋白,将此融合蛋白免疫新西兰兔,并用正辛酸-硫酸铵分步沉淀法初步纯化抗血清,ELISA法显示抗血清对HBD-2的效价为1∶12800,Western印迹显示抗血清可识别HBD-2。本实验结果证明应用重组融合小肽代替白蛋白或甲状腺-肽偶联免疫可获得其高效价的识别HBD-2的多克隆抗体,为今后从蛋白质水平研究HBD-2基因的诱导表达,包括组织分布和基因表达调控等研究打下了基础。  相似文献   
97.
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99.
免疫途径及载体对乙肝病毒DNA疫苗免疫效果影响的研究   总被引:7,自引:1,他引:6  
目的探讨DNA载体结构及接种途径对DNA疫苗免疫效果的影响。方法分别构建插入HBV表面抗原编码基因的表达载体pcDNA1.1/SA(无抗性基因)和pcDNAI/Amp/SA(含氨苄青霉素抗性基因),肌注小鼠后比较其诱生特异性免疫应答的能力;同时比较不同接种途径(肌内、皮内、皮肤划痕)及CpG免疫刺激元件(ISS)对DNA疫苗诱生免疫效果的影响。结果pcDNAI/Amp/SA的免疫效果优于pcDNA1.1/SA。pcDNA1.1/SA的免疫效果可被ISS增强,而pcDNAI/Amp/SA诱生特异性免疫应答的能力则可被ISS抑制;诱生免疫应答的能力以肌内注射最强,皮内注射免疫其次,皮下划痕法较弱。结论不同HBsAg表达载体诱生免疫应答的能力不尽相同;CpG免疫刺激元件在决定DNA疫苗免疫原性中起重要作用,可增强不含相应结构DNA疫苗的免疫效果;皮内注射可诱发与肌内接种相似的免疫应答,是一种简便、有效的免疫接种途径  相似文献   
100.
目的 比较3种不同后路经腰椎间孔椎间融合(transforaminal lumbar interbody fusion,TLIF)内固定方式的生物力学特性。 方法 建立正常L3~5有限元模型,在验证其有效性基础上模拟3种不同TLIF后路内固定方式即:单侧或双侧椎弓根螺钉内固定组(Model A和Model B)、单侧+对侧关节突螺钉固定组Model C。分别比较其在生理活动范围(Range of the motion, ROM)下模型的稳定性以及内植物的应力差异。 结果 对所有重构模型,在融合节段(L4~5)的ROM均显著下降,其中以Model B下降最多,屈伸活动减少达18.2%;内植物最大应力出现在Model C,左侧弯时达234.9 MPa;Model B的cage最大应力最小。 结论 后路双侧椎弓根螺钉固定能获得最佳稳定性,且能降低cage下沉及移位的风险;单侧+对侧关节突螺钉亦能提供较好良好的稳定。  相似文献   
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