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121.
In behavioral neurosciences, such as neurobiology and biopsychology, animal models make it possible to investigate brain-behavior relations, with the aim of gaining insight into normal and abnormal human behavior and its underlying neuronal and neuroendocrinological processes. Different types of animal models of behavioral dysfunctions are reviewed in this article. In order to determine the precise criteria that an animal model should fulfill, experts from different fields must define the desired characteristics of that model at the neuropathologic and behavioral level. The list of characteristics depends on the purpose of the model. The phenotype-abnormal behavior or behavioral dysfunctions-has to be translated into testable measures in animal experiments. It is essential to standardize rearing, housing, and testing conditions, and to evaluate the reliability, validity (primarily predictive and construct validity), and biological or clinical relevance of putative animal models of human behavioral dysfunctions. This evaluation, guided by a systematic strategy, is central to the development of a model. The necessity of animal models and the responsible use of animals in research are discussed briefly.  相似文献   
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The aims of our research were to define the genotype–phenotype correlations of mutations in the phenylalanine hydroxylase (PAH) gene that cause phenylketonuria (PKU) among the Israeli population. The mutation spectrum of the PAH gene in PKU patients in Israel is described, along with a discussion on genotype–phenotype correlations. By using polymerase chain reaction/denaturing high-performance liquid chromatography (PCR/dHPLC) and DNA sequencing, we screened all exons of the PAH gene in 180 unrelated patients with four different PKU phenotypes [classic PKU, moderate PKU, mild PKU, and mild hyperphenylalaninemia (MHP)]. In 63.2% of patient genotypes, the metabolic phenotype could be predicted, though evidence is also found for both phenotypic inconsistencies among subjects with more than one type of mutation in the PAH gene. Data analysis revealed that about 25% of patients could participate in the future in (6R)-l-erythro-5, 6, 7, 8-tetrahydrobiopterin (BH4) treatment trials according to their mutation genotypes. This study enables us to construct a national database in Israel that will serve as a valuable tool for genetic counseling and a prognostic evaluation of future cases of PKU.  相似文献   
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The most common non-Hodgkin lymphomas in Uganda are neoplasms of B-cell derivation. The field of B-cell lymphoma immunophenotype has rapidly progressed because of the increasing availability of markers applicable to routine sections. Although the latter have allowed the identification of distinctive lymphoma entities in the developed countries, such approach has not yet been used in Uganda. One hundred twenty-nine formalin-fixed, paraffin-embedded tissue samples from the Department of Pathology of Makerere University were used for tissue micro-array (TMA) construction. Four-micrometer-thick sections were cut from TMAs and stained with hematoxylin and eosin and Giemsa. They were also used for immunohistochemistry and in situ hybridization. According to morphology and immunohistochemistry, lymphoid neoplasms were classified as Burkitt's lymphoma (BL) (95 cases), diffuse large B-cell lymphoma (19 cases), mantle cell lymphoma (4 cases), and B-cell lymphoblastic lymphoma (1 case). In BL, a homogeneous phenotype (CD10(+), Bcl-6(+), Bcl-2(-), MUM1/IRF4-, and Ki-67 approximately 100%) and a stable Epstein-Barr virus integration were found. A distinctive and unusual feature was the frequent plasma cellular differentiation, along with the positivity for CD30 and CD138 (recorded in 35 and 43 cases, respectively). According to our findings, most non-Hodgkin B-cell tumors in Uganda are endemic BLs followed by diffuse large B-cell lymphomas. The rest consist of rare but clinically important entities such as mantle cell lymphoma and B-cell lymphoblastic lymphoma. The availability of TMAs and immunohistochemistry has enabled us to precisely categorize tumors that have so far been diagnosed in Uganda as "high-grade/aggressive" lymphomas on the basis of cell morphology alone.  相似文献   
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目的探讨遗传性抗凝血酶缺陷症家系表型和和基因型的关系。方法对3个遗传性抗凝血酶缺陷症家系(家系1~3)作表型和基因型诊断:常规检测活化部分凝血活酶时间(APTT)、凝血酶原时间(PT)、纤维蛋白原(Fg)、凝血酶时间(TT)以筛查凝血功能,发色底物法检测蛋白C、蛋白S和抗凝血酶活性(PC∶A,PS∶A及AT∶A),免疫比浊法检测抗凝血酶抗原(AT∶Ag),Western blot检测血浆中抗凝血酶的分子量和含量;PCR扩增AT基因所有外显子及侧翼序列,DNA测序并进行基因分析。针对新基因突变,在100例正常人中检测相应突变以排除多态性,用TA克隆PCR产物测序鉴定杂合碱基缺失突变。结果 3名先证者均为反复发作的静脉血栓患者,凝血指标及PC∶A和PS∶A都正常,AT∶A分别为正常人(100%)的60%、52%和60%,AT∶Ag分别为16.9、14.1和11.4 mg/dl,Western blot显示3位先证者的血浆AT蛋白分子量正常(58 kD)而含量低于正常;基因分析发现3名先证者各携带1个杂合突变,分别为g.8263 C>T(Leu340Phe)、g.5894-6 del TTC(Phe122del)和g.5898 T>G(Phe123Cys)。3个家系中与先证者表型相似的成员,则携带有相同的AT基因突变;但除家系2先证者的父亲有静脉血栓外,家系1和3中含有相应AT基因突变的家庭成员均无血栓发生。结论 3名先证者遗传性抗凝血酶缺陷症分别由Leu340Phe、Phe122del和Phe123Cys突变所致,其中Leu340Phe和Phe123Cys突变为国际上首次报道。  相似文献   
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目的 通过对43个中国家族性肌萎缩侧索硬化(FALS)家系先证者进行铜、锌超氧化物歧化酶(SOD)1基因突变检测,分析其与临床表型的关系,探讨中国FAIS患者SOD1基因的突变分布谱及其与临床表型之间的关联性.方法 采集2008-2011年确诊的43个FALS家系的临床资料.利用PCR技术和直接测序方法,检测先证者SOD1基因突变,进一步与临床表型做关联分析.结果 43个FALS家系均呈常染色体显性遗传,先证者男女比例为1∶0.6,起病年龄(48.1±11.8)岁,上肢起病23例,占53.5%,下肢起病18例,占41.9%,延髓部起病2例,占4.6%.在10例先证者中共发现9种SOD1突变类型,其中2种为未报道的新突变.9种突变类型中8种为错义突变,1种为缺失突变.SOD1基因突变总检出率为23.3%.结论 中国FALS患者SOD1基因突变类型由原来的11种增加到19种.具有SOD1突变的FALS患者以下运动神经元损害为主.大多数SOD1突变的临床表型在不同的家系甚至同一家系中变异均较大.  相似文献   
126.
Frailty prevalence defined by the deficit accumulation model (Frailty Index) has limited exploration in a Japanese population. The objective of this paper is to investigate the prevalence of frailty by Frailty Index among a cohort of healthy Japanese older adults, define risk factors associated with pre-frailty and frailty status and evaluate Frailty Index's agreement with Frailty Phenotype and Kihon checklist.MethodsData from 673 participants of the 2014 wave of the Nagoya Longitudinal Study - Healthy Elderly were used. Annual assessments include investigation of mood, memory, health status, nutrition, physical performance and oral health. The Frailty Index was compared to Frailty Phenotype and Kihon Checklist, and factors associated to Frailty Index were investigated through univariate and multivariate logistic regression.ResultsFrailty prevalence was 13.5% (n = 91) by Frailty Index, 1.5% (n = 10) by Frailty Phenotype and 4% (n = 27) by Kihon Checklist. Although the correlations between the three scales were moderate to high, the agreement between the scales was poor. In terms of risk factors, age, polypharmacy and physical activity level were associated with being pre-frail and frail. Having a higher waist circumference was associated with being pre-frail, and lower handgrip strength and lower walking speed were associated with being frail.ConclusionsThe Frailty Index showed similar metrics and agreement comparable to findings of previous studies, and was able to identify a higher number of individuals who were pre-frail and frail. Age, polypharmacy, physical activity, waking speed and waist circumference were associated with pre-frailty and frailty by frailty index.  相似文献   
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