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101.
Three examples of human plasma-derived concentrates, intermediate- purity factors VIII and IX, and fibrinogen were spiked with tissue culture-grown human immunodeficiency virus type 1 (HIV-1) strain RF. All examples were freeze-dried and heated at 80 degrees C for 72 hours by using validated production process models. HIV-1 infectivity was measured by a syncytial infectivity assay in C8166 cells and then compared with levels determined by nested HIV polymerase chain reaction (PCR). The infectivity assay demonstrated a reduction index of at least 4.5 log10, while PCR showed an average 1.7 log10. Large amounts of HIV- 1 RNA (10(5)) were still detectable by PCR in samples in which infectivity assays failed to detect any HIV-1. These data suggest that HIV-1 PCR levels do not parallel HIV-1 infectivity levels during virus- inactivation procedures involved in coagulation factor concentrate production. PCR was able to detect the RNA associated with inactivated HIV-1 particles in the factor concentrates, which allows the conclusion that PCR is not a useful test with which to monitor virus-inactivation procedures such as heating at 80 degrees C for 72 hours. This judgment contrasts with the more definite and sensitive role of PCR in diagnosing HIV-1 infection in patients in whom a positive HIV-1 PCR result correlates with active HIV-1 infection and with PCR's usefulness in monitoring virus removal.  相似文献   
102.
INTRODUCTION Crohn’s disease (CD) is a chronic inflammatory disease of the gastrointestinal tract which commonly affects young adults. It follows a relapsing and remitting course and there is no known cure. However, approximately 10% to 15% have chronic …  相似文献   
103.
目的 初步探讨高迁移率族蛋白B1(HMGB1)致炎效应的信号转导机制。方法 清洁级雄性Wistar大鼠,取其腹腔巨噬细胞,培养3d后以10mg/L HMGB1刺激。刺激完毕后直接在培养瓶中裂解细胞,分别采用免疫沉淀、免疫印迹法和凝胶阻滞分析等技术观察不同时间点Janus激酶2(JAK2)、信号转导及转录激活子—1(STAT1)以及STAT3的活化情况。结果 HMGB1可诱导大鼠腹腔巨噬细胞STAT1、STAT3在短时间内(2h)活化,其中STAT3活化最为迅速,10min即可达到活化高峰。但HMGB1不能在短时间内(2h)诱导JAK2活化。结论 JAK/STAT途径可能参与了HMGB1致炎效应的信号转导机制。  相似文献   
104.
目的:测量国人全膝关节假体置换术胫骨近端截骨面后缘至腘窝血管之间的距离,以期为临床全膝关节置换术中避免损伤腘窝血管提供参考数据。方法:选择2006-06/12于解放军第二军医大学长征医院体检的50名正常成人(53膝),男29名(31膝),女21名(22膝)。所有观察对象均知情同意,且得到医院伦理道德委员会批准。对所有膝关节进行MRI扫描,在胫骨外侧平台以下10mm水平横断面上辨认腘动静脉,并测量胫骨近端截骨面后缘至腘窝动静脉的距离。结果:53膝全部进入结果分析,无脱落。①男性胫骨近端截骨面后缘至腘动脉、腘静脉平均距离为(6.7±2.5,7.3±2.3)mm,95%可信区间分别为5.8~7.6mm,6.5~8.1mm。②女性胫骨近端截骨面后缘至腘动脉、腘静脉平均距离为(6.6±1.9,7.1±2.7)mm,95%可信区间分别为:5.8~7.4mm,5.9~8.3mm。③不同性别观察对象胫骨近端截骨面后缘至腘血管的距离差异无显著性意义(P>0.05)。结论:腘窝血管紧邻全膝关节假体置换术胫骨近端截骨面后缘,不同性别间无明显差异。全膝关节假体置换术中进行胫骨近端截骨,特别是后方操作时需特别谨慎,以避免损伤腘窝血管。  相似文献   
105.
106.
Previous studies have demonstrated a modest association between smoking and leukemia particularly for myeloid disorders. Our objective was to examine whether changing trends in cigarette smoking prevalence nationally and within selected states parallel similar trends in mortality from leukemia. Trends in national smoking rates were correlated with trends in leukemia mortality rates obtained from the Centers for Disease Control and Prevention and the Surveillance Epidemiology and End Results registry, respectively. State-specific correlations were assessed from 1984 to 2004 using smoking prevalence data from the Behavioral Risk Factor Surveillance System and leukemia mortality data from National Vital Statistics System. Correlations were computed using the Spearman rank correlation coefficient. Leukemia mortality decreased overall in the United States in parallel with decreased smoking. Analyzed on a state-specific basis, leukemia mortality decreased in states where smoking rates declined markedly but remained unchanged where smoking prevalences were relatively stable. The findings suggest that declining rates of leukemia mortality are associated with changing patterns of smoking behavior.  相似文献   
107.
Anophthalmia (no eye), microphthalmia (small eye) and associated ocular developmental anomalies cause significant visual handicap. In most cases the underlying genetic cause is unknown, but mutations in some genes, such as SOX2, cause ocular developmental defects, particularly anophthalmia, in a subset of patients. Here, we describe a four-generation family with a p.Asp123Gly mutation in the highly conserved partner-factor interaction region of the SOX2 protein, which is important for cell-specific actions of SOX2. The proband in this family has bilateral anophthalmia and several other family members have milder ocular phenotypes, including typical optic fissure coloboma. Expression studies indicate that Sox2 is expressed in the eye at the site of closure of the optic fissure during development. The SOX2 mutation in this family implicates the partner-factor interaction region of SOX2 in contributing to the specificity of SOX2 action in optic fissure closure. Our findings indicate that investigation of SOX2 in a broad range of eye anomaly patients aids in the determination of particular functions of SOX2 in development.  相似文献   
108.
This study describes the use of cerebral spinal fluid (CSF) and/or urine as source of DNA for mutation analysis combined with multiple displacement amplification. The findings illustrate the opportunities and pitfalls of these methods in the search for identification of the pathogenic mutations in the case that only scarce material is available such as CSF.  相似文献   
109.
The hph-1 mouse has low liver activity of GTP cyclohydrolase 1, the rate limiting enzyme in the biosynthesis of tetrahydrobiopterin (BH4). BH4 is the cofactor for phenylalanine hydroxylase (PAH) and in the early stages of life the hph-1 mouse is hyperphenylalaninemic. At approximately 15 days after birth the blood phenylalanine levels normalize. During this period the animals provide an in vivo model which can be used to study the regulatory effects of phenylalanine on PAH, and for related pediatric metabolic disease in humans; from birth to youth. We therefore, examined; liver PAH activity using BH4 and 6-methyltetrahydropterin (6MPH4) as cofactor; PAH total enzyme concentration by Western blotting using the PH8 antibody, and PAH state of phosphorylation using the PH7 antibody from 4 to 18 days after birth. The findings were compared to the wild type animals that are not hyperphenylalaninemic during this period. PAH (6MPH4) activity and total protein (PH8 antibody) rose steadily in the hph-1 mice. In control mice, both activity and total protein fluctuated. The degree of phosphorylation of PAH in the mutants and the state of activation (as measured by the 6MPH4/BH4 activity ratio) increased as phenylalanine levels rose, and decreased when they fell. Similar patterns were not seen in the control animals. These studies provide in vivo evidence that phenylalanine concentration regulates the activity of PAH in the hph-1 mouse and that this acts via a mechanism that includes phosphorylation of the PAH molecule. The kinetic values (Km and Vmax) for mouse PAH are also reported.  相似文献   
110.
OBJECTIVES: The aim of this study was to test a motivational interpretation of placebo responding using two different types of placebo therapy, one using flower essences and the other a nonspecific psychological therapy. The motivational concordance interpretation is that therapeutic rituals that are consistent with self-defining or self-actualizing goals have a nonspecific therapeutic benefit independently of expectancy. METHODS: Study 1 was a replication of an earlier flower essence outcome study but with additional outcome and predictor variables: 167 people completed questionnaires in return for free flower essence treatment. Predictor variables consisted of two measures of spirituality, optimism, expectancy, and attitudes and beliefs to complementary medicine. Outcome was assessed after 3 weeks. In Study 2, 90 people took part in "gratitude therapy" for improved sleep quality over one night in return for questionnaire completion (trait gratitude, spirituality, and expectancy). RESULTS: Study 1 confirmed previous research: Trait spirituality predicted perceived improvement. This improvement was independent of optimism (P<.001), cannot be explained by acquiescence or social desirability, and was independent of a highly conservative test of expectancy (P=.02). In Study 2, trait gratitude predicted perceived sleep improvement independently of expectancy (P=.01): Spirituality did not correlate with improvement. CONCLUSIONS: These data suggest that in addition to expectations, degree of engagement in a positive, therapeutic ritual determines the extent of the placebo response. The placebo response depends in part on the interaction (i.e., the degree of concordance) between the type of therapy and the participant's personality: Dispositional predictors vary with the type of placebo therapy.  相似文献   
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