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71.
BACKGROUND: A vaccine is needed to prevent human immunodeficiency virus type 1 (HIV-1) infection. METHODS: A double-blind, randomized trial of a recombinant HIV-1 envelope glycoprotein subunit (rgp120) vaccine was conducted among men who have sex with men and among women at high risk for heterosexual transmission of HIV-1. Volunteers received 7 injections of either vaccine or placebo (ratio, 2 : 1) over 30 months. The primary end point was HIV-1 seroconversion over 36 months. RESULTS: A total of 5403 volunteers (5095 men and 308 women) were evaluated. The vaccine did not prevent HIV-1 acquisition: infection rates were 6.7% in 3598 vaccinees and 7.0% in 1805 placebo recipients; vaccine efficacy (VE) was estimated as 6% (95% confidence interval, -17% to 24%). There were no significant differences in viral loads, rates of antiretroviral-therapy initiation, or the genetic characteristics of the infecting HIV-1 strains between treatment arms. Exploratory subgroup analyses showed nonsignificant trends toward efficacy in preventing infection in the highest risk (VE, 43%; n=247) and nonwhite (VE, 47%; n=914) volunteers (P=.10, adjusted for multiple subgroup comparisons). CONCLUSIONS: There was no overall protective effect. The efficacy trends in subgroups may provide clues for the development of effective immunization approaches.  相似文献   
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73.
Sixty healthy nonresponders were randomized to receive intramuscular (IM) high dose hepatitis B virus (HBV) vaccine versus IM standard dose HBV vaccine plus granulocyte-macrophage colony-stimulating factor (GM-CSF) at 0-2 months. Antibody to hepatitis B surface antigen was measured 1 month after each dose and 3 months after the last dose. Two regimens were equivalent in eliciting seroprotection in nonresponders. Weight-height index (WHI) <39 and alanine transaminase (ALT) <39 mg/dl predicted which nonresponders would seroconvert. A three-dose regimen of standard dose HBV vaccine plus GM-CSF may be a useful for seroprotection of healthy nonresponders.  相似文献   
74.
OBJECTIVE: To study the relationship between QT interval dispersion, arterial hypertension and different left ventricular geometric patterns in the framework of a population study. DESIGN: A random sample of the population of Tallinn, 717 men and women aged 35-59, underwent standard 12-lead ECG at rest and echocardiography. Corrected QT dispersion was considered as prolonged when the duration was > or =70 ms. RESULTS: In hypertensives with concentric and eccentric hypertrophy, the mean values of corrected QT dispersion were significantly higher than in those with normal geometry. In the normotensive group no significant differences of the mean values of corrected QT dispersion were found in relation to left ventricular geometry. Mean values of corrected QT dispersion were higher in hypertensives than in normotensives in each left ventricular geometric pattern. Corrected QT dispersion > or =70 ms was mainly associated with concentric hypertrophy. CONCLUSION: Prolonged corrected QT dispersion is associated with left ventricular geometric abnormalities and arterial hypertension and is mostly related to concentric hypertrophy.  相似文献   
75.
Ohne ZusammenfassungMit 7 Textabbildungen (13 Einzelbilder)Herrn Professor Dr. H. Kuntzen zum 65. Geburtstag gewidmet.  相似文献   
76.
1. Cholecystokinin and benzodiazepine receptor binding was evaluated in 2-, 9- and 18-month old rats in the brain regions where cholecystokinin octapeptide and gamma-aminobutyric acid are known to coexist in common nerve cells (frontal cortex, hippocampus). 2. There was a regionally selective alteration of hippocampal 3H-CCK-8 binding in the oldest age group, if compared to both young and adult animals. Non-linear regression analysis of binding data revealed significantly lower apparent number of binding sites (Bmax), and twofold (but not statistically significantly) higher binding affinity for the radiolabelled ligand. No differences between any age groups in 3H-flunitrazepam binding to benzodiazepine receptors were found. 3. The results suggest that changes in cholecystokinin receptor characteristics might contribute to the behavioural impairments in aged rats.  相似文献   
77.
78.
Intracerebrally administered CRF has been demonstrated to elicit several behavioural deficits in novel and potentially stressful experimental paradigms, and to promote activity in familiar situations. This study examined the effect of CRA 1000, a novel non-peptide antagonist of CRF(1)receptors, on rat behaviour in tests of anxiolytic and antidepressant activity and novelty-oriented behaviour. CRA 1000 (1.25-10 mg/kg) had no major effect in elevated plus-maze and social interaction tests. However, CRA 1000 (5 mg/kg) significantly reduced immobility in the forced swimming test, suggesting an antidepressant-like effect. In the exploration box test, CRA 1000 (1.25 mg/kg) had an anxiolytic effect on rat exploratory behaviour both in intact rats and after lesioning of the projections of locus coeruleus by DSP-4 (50 mg/kg) treatment. A higher dose of CRA 1000 (5 mg/kg) tended to have anxiolytic-like effects in DSP-4 pretreated rats, but in intact animals this dose prevented the increase in exploration which develops with repeated exposure to initially anxiety-provoking situations. Taken together, these experiments demonstrate that CRF1 receptor blockade by CRA 1000 has antidepressant-like effects, does not have a robust anti-anxiety effect in non-stressed animals, but does have anxiolytic-like effects in more complex tasks, which can be observed also after denervation of the locus coeruleus projections. However, large doses of CRF1 receptor antagonists may reduce motivation of exploratory behaviour in familiar environments.  相似文献   
79.
Chronic variable stress (CVS) and manipulations of 5-HT-ergic neurotransmission are increasingly used as animal models of depression. In the present study, CVS for 2 weeks and a partial lesion of 5-HT projections by a small dose of parachloroamphetamine (PCA, 2 mg/kg) were applied independently or in combination. CVS reduced significantly the gain in body weight and increased the number of defecations in the open field test. PCA reduced body weight only within the first 24 h after its administration. Consumption of sucrose solution and its preference to water in non-deprived rats were significantly higher in PCA-pretreated rats 2 weeks after CVS compared to control animals. In the forced swimming test, both PCA and CVS treatments reduced immobility on the first but not the second session. Both treatments reduced significantly the time rats spent in social interaction. CVS also elicited an increase in the weight of the right adrenal, but this effect was not present in the PCA-pretreated group. PCA reduced 5-HT and 5-HIAA levels in the frontal cortex, hippocampus, and septum by approximately 20%. CVS increased HVA levels in the frontal cortex. Applied together, PCA pretreatment and CVS increased dopamine turnover in the frontal cortex. Conclusively, this study has provided evidence that chronic variable stress, which elicited expected physiological and neurochemical changes, does not reduce sucrose intake or preference in non-deprived animals, but, instead, may increase it after partial 5-HT-ergic denervation; and that partial 5-HT-ergic denervation by a low dose PCA treatment has a long-lasting effect on forced swimming and social behavior similar to chronic stress.  相似文献   
80.
BACKGROUND: Studies in animal models have shown that systemic immunization with a papillomavirus virus-like particle (VLP) vaccine composed of L1, a major structural viral protein, can confer protection against subsequent experimental challenge with the homologous virus. Here we report results of a double-blind, placebo-controlled, dose-escalation trial to evaluate the safety and immunogenicity of a human papillomavirus (HPV) type 16 (HPV16) L1 VLP vaccine in healthy adults. METHODS: Volunteers were given intramuscular injections with placebo or with 10- or 50-microg doses of HPV16 L1 VLP vaccine given without adjuvant or with alum or MF59 as adjuvants at 0, 1, and 4 months. All vaccine recipients were monitored for clinical signs and symptoms for 7 days after each inoculation. Immune responses were measured by an HPV16 L1 VLP-based enzyme-linked immunosorbent assay (ELISA) and by an HPV16 pseudovirion neutralization assay. The antibody titers were given as the reciprocals of the highest dilution showing positive reactivity in each assay. All statistical tests were two-sided. RESULTS: The prevaccination geometric mean ELISA titer for six seropositive individuals was 202 (range, 40--640). All vaccine formulations were well tolerated, and all subjects receiving vaccine seroconverted. Serum antibody responses at 1 month after the third injection were dose dependent in recipients of vaccine without adjuvant or with MF59 but were similar at both doses when alum was the adjuvant. With the higher dose, the geometric means of serum ELISA antibody titers (95% confidence intervals) to purified VLP 1 month after the third injection were as follows: 10,240 (1499 to 69 938) without adjuvant, 10,240 (1114 to 94 145) with MF59, and 2190 (838 to 5723) with alum. Responses of subjects within each group were similar. Neutralizing and ELISA antibody titers were highly correlated (Spearman correlation =.85), confirming that ELISA titers are valid proxies for neutralizing antibodies. CONCLUSIONS: The HPV16 L1 VLP vaccine is well tolerated and is highly immunogenic even without adjuvant, with the majority of the recipients achieving serum antibody titers that were approximately 40-fold higher than what is observed in natural infection.  相似文献   
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