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41.
Background: In many developed countries tuning supply and demand of medical doctors is a continuous challenge to meet the ever changing needs of community and individual patients. The long study period for medical doctors creates the opportunity to observe the current career preferences of medical students and evolution in time.

Objectives: To investigate the career choices of Polish students in different stages of their medical education.

Methods: Medical students at five Polish medical universities were questioned about their career aspirations in the first, third and sixth year.

Results: A total of 2020 students were recruited for the survey. Among first year students 17% preferred family medicine as final career option, compared to 20% in the third year, and 30% in the sixth year (significant trend, P < 0.0001). In particular, female students prefer family medicine: 71% women versus 62% women in the group with a preference for a non-family medicine orientation (P = 0.008). Medical students rejecting a career as a family doctor stated that the impossibility to work in a hospital environment was the determining factor.

Conclusion: The opportunity for professional development seems to be an important determining factor in the choice of a medical specialty in Poland. The proportion of Polish students choosing family medicine increases during their progress in medical education, with one third of students interested in a career in family medicine by year six.  相似文献   

42.
The development of epithelial ovarian cancer is associated with changes in the peritoneal cavity microenvironment. Tumor cells produce different factors, which impairs differentiation, maturation, and function of antigen-presenting cells. In this review, we focus on selected cell populations in the peritoneal cavity immune system and their potential role in epithelial ovarian cancer immunopathogenesis. We devote most attention to dendritic cells because they are considered to be superior in their antigen-presenting ability, compared with both macrophages and B lymphocytes. We also present a brief characterization of tumor-infiltraiting cells in epithelial ovarian cancer patients.  相似文献   
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GLT1 is one of the major transporters responsible for maintenance of glutamate homeostasis in the brain. In the present study, glutamate transporter 1-deficient GLT1 homozygous (-/-) and heterozygous (+/-) mice were investigated with the intention that they may provide a model of hyperglutamatergic state resulting in various behavioral alterations. The GLT1 (-/-) mice had lower body and brain weight, mild neuronal loss in CA1 hippocampal region as well as focal gliosis and severe focal neuronal paucity in layer II of the neocortex. The short life-span of GLT1 (-/-) precluded us from systematic behavioral studies in these mice. In contrast, GLT1 (+/-) mice exhibiting a 59% decrease in GLT1 immunoreactivity in their brain tissue, showed no apparent morphological brain abnormalities, and their life-span was not markedly different from controls. Behaviorally, GLT1 (+/-) presented moderate behavioral alterations compared to their wildtype littermates, such as: mild sensorimotor impairment, hyperlocomotion (at 3 month of age only), lower anxiety (at 6 months), better learning of cue-based fear conditioning but worse context-based fear conditioning. Our results suggest that GLT1 (+/-) mice may serve as a potentially useful model to study neurodegenerative disease conditions with mild hyperglutamatergic activity.  相似文献   
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This study examined the effect of leptin on renal ouabain-resistant Na(+)-ATPase, which drives the reabsorption of about 10% of sodium transported in the proximal tubule. Chronic leptin administration (0.25 mg/kg s.c. twice daily for seven days) increased Na(+)-ATPase activity by 62.9%. This effect was prevented by the coadministration of superoxide dismutase mimetic, tempol, or the NADPH oxidase inhibitor, apocynin (2 mM in the drinking water). Acutely administered NO donors decreased Na(+)-ATPase activity. This effect was abolished by soluble guanylate cyclase inhibitor, ODQ, but not by protein kinase G inhibitors. Exogenous cGMP reduced Na(+)-ATPase activity, but its synthetic analogues, 8-bromo-cGMP and 8-pCPT-cGMP, were ineffective. The inhibitory effect of NO donors and cGMP was abolished by EHNA, an inhibitor of cGMP-stimulated phosphodiesterase (PDE2). Exogenous cAMP analogue and dibutyryl-cAMP increased Na(+)-ATPase activity and abolished the inhibitory effect of cGMP. Finally, the administration of superoxide-generating mixture (xanthine oxidase+hypoxanthine) increased Na(+)-ATPase activity. The results suggest that nitric oxide decreases renal Na(+)-ATPase activity by stimulating cGMP, which in turn activates PDE2 and decreases cAMP concentration. Increased production of reactive oxygen species may lead to the elevation of Na(+)-ATPase activity by scavenging NO and limiting its inhibitory effect. Chronic hyperleptinemia is associated with increased Na(+)-ATPase activity due to excessive oxidative stress.  相似文献   
48.

Altered parvalbumin (PV) expression is observed in the prefrontal cortex of subjects with schizophrenia. Environmental context, particularly during adolescence, might regulate PV expression. In the present study, we investigated the effect of adolescent social isolation (SI) on PV expression in the medial prefrontal cortex in a neurodevelopmental model (MAM-E17) of schizophrenia. SI exposure occurred from postnatal day 30 to 40, followed by resocialization until late adolescence or early adulthood. PV mRNA and protein levels, as well as the number of PV cells, were analysed at these ages. Moreover, epigenetic regulation of PV expression by histone methylation was examined by measuring the total and PV gene-bound H3K4me3 levels. MAM only decreased levels of the PV mRNA and protein in adulthood. Decreases in total H3K4me3 levels and its level at the PV gene were also observed at this age. In contrast, in late adolescence, SI induced a decrease in the expression of the PV mRNA in the MAM group that was related to the reduction in total and PV gene-bound H3K4me3 levels. However, at this age, SI increased the levels of the PV protein in both the control and MAM groups. In adulthood, SI did not affect PV mRNA or H3K4me3 levels but decreased levels of the PV protein in both groups. Both MAM and SI failed to change the number of PV cells at any age. The results indicate that adolescent SI accelerated epigenetic impairments of PV expression in MAM-E17 rats; however, subsequent resocialization abolished this dysfunction, but failed to prevent alterations in PV protein.

  相似文献   
49.
Antiphospholipid syndrome (APS) is a systemic autoimmune disorder, where the essence of the matter is the existence of antiphospholipid antibodies. The typical symptoms of APS are: venous thrombo-embolic disease and artery thrombosis in a brain. The authors present 5 patients (2 females and 3 males) at the age of 36-54 with ischemic stroke and one 26-year-old women with thrombosis of central retinal vein caused by APS. In 4 cases in secondary prevention anticoagulant (acenocumarol) was used and in 2--antiplatelet drug (aspirin). In 2 cases congenital disturbances of coagulation were also discovered. We suggest that in ischemic stroke and visual disturbances of not-well-known origin it is useful to make examinations concerning APS, as well as congenital thrombophilias.  相似文献   
50.

Objectives

This study explored the relationship between oxidative stress biomarkers and stability of carotid plaque. We decided to analyze the broad range of parameters describing oxidative stress in patients with carotid stenosis.

Design and methods

124 consecutive patients undergoing carotid endarterectomy were enrolled in the study group. The control group consisted of 49 patients without symptoms of atherosclerosis. The stability of carotid plaques was assessed using GSM (gray-scale median) scoring system and the study group was divided into three subgroups according to echogenicity of the plaque. The following parameters of oxidative stress/DNA damage were analyzed: i) urinary excretion of the products of oxidative DNA damage repair; ii) the background level of 8-oxo-7,8-dihydro-2′-deoxyguanosine in leukocytes' DNA and in atherosclerotic plaques; and iii) the concentrations of antioxidant vitamins, uric acid and C-reactive protein in plasma.

Results

Oxidative stress (described by redox status) was higher in the patient group than in the control group. There is a correlation between oxidative stress of the patients and stability of the plaque, echolucent plaques (GSM < 25) being associated with the highest antioxidant level and lowest excretion of DNA repair markers.

Conclusions

The plaque formation/morphology may depend on local environment and is independent of oxidative stress/inflammation observed on the level of the whole body.  相似文献   
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