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311.
Tea drinking has been suggested to be beneficial in neurodegenerative diseases where depressive mood is a common symptom. Nevertheless, it is not known whether there are any associations between tea drinking and depression in general populations. In this study we investigated these associations in a sample of the Finnish general population (n = 2011) using a postal questionnaire and the Beck Depression Inventory (BDI). Those who reported drinking tea daily were less depressed than the others. They had a lower mean BDI score and also a lower prevalence of depression. None of those whose daily tea intake was five cups or more had depression. Several potential confounding factors were included in the final sex- and age-adjusted multivariate logistic regression model which suggested that those who drink tea daily may have a significantly reduced risk of being depressed (adjusted odds ratio 0.47, 95 confidence interval 0.27–0.83). In conclusion, an inverse relationship between daily tea drinking and the risk of being depressed was found in a relatively large general population sample. Nevertheless, the underlying mechanisms are unresolved and further studies are needed.  相似文献   
312.
We investigated the association between cognitive performance and major depressive disorder (MDD) in adolescents seeking outpatient treatment. We used several tests comparing cognitive capacities between 16 adolescents with MDD and 25 adolescents not diagnosed as suffering from psychiatric illness according to the Structured Clinical Interview for DSM-III-R (SCID). No difference in neuropsychological test performance was found between adolescents with MDD and those without psychiatric diagnosis. Logistic regression analysis showed the only independent factor associated with MDD to be Emotional Tone (S2; odds ratio 1.13). The specific effects of MDD on the adolescents were restricted to the emotional area and were expressed as a broad deterioration in psychosocial functioning.  相似文献   
313.
The cell surface adhesion molecule Mel-CAM is highly expressed in advanced primary and metastatic melanoma. Mel-CAM was first described as an integral membrane glycoprotein of malignant melanoma cells. The murine monoclonal antibody MAd18-5D7 recognizes an epitope of the extracellular domain of Mel-CAM and is able to enhance Mel-CAM mediated adhesion of melanoma cells in aggregation assays. For the characterization of peptides that antigenically mimic surface-exposed areas of Mel-CAM we screened a newly constructed random pVIII-28aa bacteriophage peptide library against MAd18-5D7. After three panning rounds a population of phages binding to MAd18-5D7 was enriched. Peptides expressed on the surface of these phages were then tested for their specificity for the antibody's antigen binding site. DNA sequences coding for two specific peptide ligands were determined. One of the deduced amino acid sequences showed similarity to a portion of the sequence of the third immunoglobulin-like extracellular domain of Mel-CAM. Both peptides blocked the interaction of MAd18-5D7 with Mel-CAM present in a MelJuSo melanoma cell line lysate. Phage displayed as well as synthetic peptides inhibited in a dose-dependent manner the binding of MAd18-5D7 to recombinant Mel-CAM in enzyme-linked immunosorbent assay experiments. No such inhibition was observed using a panel of other anti-Mel-CAM antibodies. Our results clearly indicate that these 28mer peptides are structural equivalents of the MAd18-5D7 epitope of Mel-CAM and that they will be useful tools for further in vitro and in vivo studies of Mel-CAM mediated cell-cell interaction.  相似文献   
314.
CONTEXT: The pathogenesis of high-altitude pulmonary edema (HAPE) is considered an altered permeability of the alveolar-capillary barrier secondary to intense pulmonary vasoconstriction and high capillary pressure, but previous bronchoalveolar lavage (BAL) findings in well-established HAPE are also consistent with inflammatory etiologic characteristics. OBJECTIVES: To determine whether inflammation is a primary event in HAPE and to define the temporal sequence of events in HAPE. DESIGN, SETTING, AND PARTICIPANTS: Case study from July through August 1999 of 10 subjects with susceptibility to HAPE and 6 subjects resistant to HAPE, all of whom are nonprofessional alpinists with previous mountaineering experience above 3000 m. MAIN OUTCOME MEASURES: Pulmonary artery pressure measurements and BAL findings at low altitude (490 m) and shortly before or at the onset of HAPE at an altitude of 4559 m. RESULTS: Subjects who were HAPE susceptible had higher mean (SD) pulmonary artery systolic blood pressures at 4559 m compared with HAPE-resistant subjects (66 vs 37 mm Hg; P =.004). Despite development of HAPE in the majority of HAPE-susceptible subjects, there were no differences in BAL fluid total leukocyte counts between resistant and susceptible subjects or between counts taken at low and high altitudes. Subjects who developed HAPE had BAL fluid with high concentrations of plasma-derived proteins and erythrocytes, but there was no increase in plasma concentrations of surfactant protein A and Clara cell protein. The chest radiograph score was 12.7 for the 3 HAPE-susceptible subjects who developed HAPE before BAL was performed; they were lavaged within 3 to 5 hours. The remainder of the HAPE-susceptible group was lavaged before edema was apparent on radiographs. However, 6 subjects from the HAPE-susceptible group who developed HAPE on the following day had a score on bronchoscopy of 1.5, which increased to 4.6, reflective of mild pulmonary edema. In HAPE cases, there were no elevations in a number of proinflammatory cytokines and eicosanoid and nitric oxide metabolites. CONCLUSIONS: Early HAPE is characterized by high pulmonary artery pressures that lead to a protein-rich and mildly hemorrhagic edema, with normal levels of leukocytes, cytokines, and eicosanoids. HAPE is a form of hydrostatic pulmonary edema with altered alveolar-capillary permeability.  相似文献   
315.
Evolutionary biology of plant food allergens   总被引:1,自引:1,他引:0  
The majority of plant food allergens can be grouped into just 4 protein families. This review summarizes the evolutionary relationships of allergenic and nonallergenic members of these families. Proteins from the prolamin superfamily have been described in vascular plants. This superfamily contains several allergenic (2S albumins, nonspecific lipid transfer proteins, and cereal amylase and protease inhibitors) and nonallergenic (hybrid proline-rich proteins, cereal indolines, and alpha-globulins) member families. The cupin superfamily comprises numerous functionally highly diverse protein families from all groups of organisms. However, allergenicity within the cupins is confined to the vicilin and legumin seed storage proteins. Profilins are ubiquitous eukaryotic proteins that are nonallergenic, with the exception of profilins from flowering plants. Finally, the Bet v 1 superfamily contains the pathogenesis-related proteins 10 family, the family of major latex proteins and ripening-related proteins, the norcoclaurine synthases, and the cytokinin-binding proteins, with pathogenesis-related proteins 10 family members from certain taxa being the only allergenic members. The study of the distribution of allergenic and nonallergenic members of protein families will provide new insights into the evolution of allergenicity and the factors that make proteins allergenic.  相似文献   
316.
Borderline personality disorder (BPD) and chronic depression (CD) are common and challenging mental disorders. Maladaptive cognitive schemas have been proposed to increase vulnerability to both disorders. In order to elucidate the role of maladaptive cognitive schemas in BPD and CD, this study compared psychiatric outpatients with BPD (N = 30) and CD (N = 30) in terms of early maladaptive schemas (EMSs). The groups were compared using the Young Schema Questionnaire short form‐extended (YSQ‐S2‐extended) and the 15D health status questionnaire. BPD patients showed higher endorsement on the majority of EMSs, poorer social functioning, and greater concurrent distress than CD patients. However, after controlling for concurrent effects of psychological distress, the groups did not differ in 14 out of the 18 EMSs. These findings point to significant similarities in maladaptive beliefs between the 2 disorders and do not support broad, specific patterns of EMSs associated with either disorder. The results highlight the need for further study of the role of maladaptive schemas in the development and treatment of chronic mental disorders.  相似文献   
317.
Cardiac unloading with left ventricular assist devices is increasingly used to treat patients with severe heart failure. Unloading has been shown to improve systolic and diastolic function, but its impact on the repolarization of left ventricular myocytes is not known. Unloaded hearts exhibit similar patterns of gene expression as hearts subjected to an increased hemodynamic load. We therefore hypothesized that cardiac unloading also replicates the alterations in action potential and underlying repolarizing ionic currents found in pressure-overload induced cardiac hypertrophy. Left ventricular unloading was induced by heterotopic heart transplantation in syngenic male Lewis rats. Action potentials and underlying K+ and Ca2+ currents were investigated using whole-cell patch-clamp technique. Real-time RT-PCR was used to quantify mRNA expression of Kv4.2, Kv4.3, and KChIP2. Unloading markedly prolonged cardiac action potentials and suppressed the amplitude of several repolarizing K+ currents, in particular of the transient outward K+ current Ito, in both, epicardial and endocardial myocytes. The reduction of Ito was associated with significantly lower levels of Kv4.2 and Kv4.3 mRNAs in epicardial myocytes, and of KChIP2 mRNA in endocardial myocytes. Concomitantly, the L-type Ca2+ current was increased in myocytes of unloaded hearts. Collectively, these results show that left ventricular unloading induces a profound remodelling of cardiac repolarization with action potential prolongation, downregulation of repolarizing K+ currents and upregulation of the L-type Ca2+ current. This indicates that unloaded rat hearts in vivo express a hypertrophic phenotype of cardiac repolarization at the cellular and the molecular level.  相似文献   
318.
The ‘discovery’ of lipid droplets as a metabolically highly active subcellular organelle has sparked great scientific interest in its research in recent years. The previous view of a rather inert storage pool of neutral lipids—triacylglycerol and sterols or steryl esters—has markedly changed. Driven by the endemic dimensions of lipid-associated disorders on the one hand, and the promising biotechnological application to generate oils (‘biodiesel’) from single-celled organisms on the other, multiple model organisms are exploited in basic and applied research to develop a better understanding of biogenesis and metabolism of this organelle. This article summarizes the current status of LD research in yeast and experimental approaches to obtain insight into the regulatory and structural components driving lipid droplet formation and their physiological and pathophysiological roles in lipid homeostasis.  相似文献   
319.
Residual symptoms of depression after psychiatric treatment are strong predictors of early relapses. The initial treatment process should therefore be effective enough to prevent such symptoms. We conducted a 3-month follow-up study to determine what factors prevented clear alleviation of depressive symptoms (Beck Depression Inventory (BDI) score of <10 at follow-up and a BDI score decrease of at least 30%) in 45 patients treated in specialized psychiatric outpatient care. All of the patients had a DSM-III-R depressive disorder. Fifty-six per cent showed signs of partial remission after 12 weeks of treatment. Those showing signs of partial remission did not differ from those having recovered in terms of sociodemographic or clinical (including BDI score) variables at base line. Certain life events occurring during treatment were associated with partial remission. Those who recovered were more satisfied with their therapy process than those experiencing partial remission, and their life satisfaction was greater, but this could have been a result of alleviation of their depression. Patients who do not respond to treatment should be carefully re-evaluated to discover possible new stressful life events.  相似文献   
320.
The immature host is prone to the passage of bacteria across the gut mucosal barrier. Corticosteroids accelerate the maturation of the intestinal mucosa and alter the composition of the gut bacterial flora. The present study was performed to assess the effect of prenatal cortisone on bacterial translocation in the neonatal rat. Time-pregnant Sprague Dawley rats were randomized on the 19th day of gestation for intraperitoneal injection of either 20 mg/100 g body weight of hydrocortisone or saline. Rats delivered spontaneously and the offspring were suckled ad libitum by the dam. Rat pups (N = 82) were killed 1 or 9 days after delivery. Mesenteric lymph nodes, liver, heart blood, and the terminal ileal loop were excised and quantitatively analyzed for bacteria. After one day, the proportion of rats with positive translocation was not significantly different between the two treatment groups (saline 62%, cortisone 80%, P = NS). By day 9, translocation had increased in the saline group (P = 0.03 vs day 1), did not significantly change in the cortisone group, and was significantly lower in rats treated with cortisone compared with the saline control (saline 90%, cortisone 60%, P = 0.02). The decrease in bacterial translocation after treatment with cortisone was associated with significantly lower total bacterial counts in the ileum (P < 0.05). Cortisone did not reduce bacterial counts in extraintestinal organs with positive translocation. In conclusion, prenatal treatment with cortisone reduces the incidence of spontaneous bacterial translocation from the intestine but not the concentration of translocated bacteria in extraintestinal organs of 9-day-old rats. Cortisone-induced changes of the intestinal microflora may have contributed to the reduction in translocation frequency.  相似文献   
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