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BACKGROUND: Since the measles resurgence of 1989-1991, which affected predominantly inner-city preschoolers, national vaccination rates have risen to record-high levels, but rates among inner-city, preschool-aged, African-American children lag behind national rates. The threat of measles importations from abroad exists and may be particularly important in large U.S. cities. To stop epidemic transmission, measles vaccination coverage should be at least 80%. OBJECTIVE: To determine measles vaccination rates and predictors for having received a dose of measles-containing vaccine by age 19 to 35 months among children in an inner-city community of Chicago.METHODS: We used a cross-sectional survey with probability proportional to size cluster sampling. Immunization histories from parent-held records and providers were combined to establish a complete vaccination history. RESULTS: A total of 2545 households were contacted, and 170 included a resident child aged 12 to 35 months. Of these, 97% (N=165 children) agreed to participate. Immunization history from a parent or provider was not available for 20 children. Among children aged 19 to 35 months with available immunization histories, 74% received measles vaccine (n=100); of these, 84% received the vaccine as recommended at ages 12 to 15 months. However, when including children without immunization histories, measles coverage levels among children aged 19 to 35 months were 64% (n=114). Among children with records, predictors for receipt of measles vaccine by age 19 to 35 months were possessing a hand-held immunization card (odds ratio [OR]=16.8; 95% confidence interval [CI]=4.2-67.1); utilizing a public health department provider for a usual source of care (OR=8.9; 95% CI=1.6-47.2); and being up-to-date for vaccines at 3 months of age (OR=5.0; 95% CI=1.8-14.1). CONCLUSIONS: Optimistically assuming that children without immunization histories are as well immunized as children with immunization histories, the measles vaccination rate among Englewood's children aged 19 to 35 months is too low to maintain immunity (74%). Measles coverage levels lagged behind coverage reported in a national survey in Chicago (86%) and the nation as a whole (92%). Efforts to raise and sustain coverage should be undertaken.  相似文献   
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Adenosine A(2A) receptor antagonists have been proposed as an effective therapy in the treatment of Parkinson's disease. To explore the possibility that dopamine denervation may produce modifications in adenosine A(2A) transmission, we measured the extracellular concentration of adenosine and adenosine A(2A) receptor mRNA in the striatum of rats infused unilaterally with 6-hydroxydopamine in the medial forebrain bundle. Fifteen days after 6-hydroxydopamine infusion, extracellular adenosine levels, measured by in vivo microdialysis, were significantly lower (-35%) in the dopamine-denervated striatum. At the time of the decrease in adenosine levels, an increase in striatal adenosine A(2A) receptor mRNA levels (+20%), measured by in situ hybridization, was observed. Modifications in adenosine A(2A) transmission, following nigrostriatal dopamine neuron degeneration, establish a potential neural basis for the effectiveness of adenosine A(2A) receptor antagonists in the treatment of Parkinson's disease.  相似文献   
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1. Ischemic preconditioning in the brain consists of reducing the sensitivity of neuronal tissue to further, more severe, ischemic insults. We recorded field epsps (fepsps) extracellularly from hippocampal slices to develop a model of in vitro ischemic preconditioning and to evaluate the role of A1, A2A and A3 adenosine receptors in this phenomenon. 2. The application of an ischemic insult, obtained by glucose and oxygen deprivation for 7 min, produced an irreversible depression of synaptic transmission. Ischemic preconditioning was induced by four ischemic insults (2 min each) separated by 13 min of normoxic conditions. After 30 min, an ischemic insult of 7 min was applied. This protocol substantially protected the tissue from the irreversible depression of synaptic activity. 3. The selective adenosine A1 receptor antagonist, 8-cyclopentyl-1,3-dipropylxanthine (DPCPX, 100 nm), completely prevented the protective effect of preconditioning. The selective adenosine A2A receptor antagonist 4-(2-[7-amino-2-(2-furyl)[1,2,4]triazolo[2,3-a][1,3,5]triazin-5-ylamino]ethyl)phenol (ZM 241385, 100 nm) did not modify the magnitude of fepsp recovery compared to control slices. The selective A3 adenosine receptor antagonists, 3-propyl-6-ethyl-5[ethyl(thio)carbonyl]-2-phenyl-4-propyl-3-pyridinecarboxylate (MRS 1523, 100 nm) significantly improved the recovery of fepsps after 7 min of ischemia. 4. Our results show that in vitro ischemic preconditioning allows CA1 hippocampal neurons to become resistant to prolonged exposure to ischemia. Adenosine, by stimulating A1 receptors, plays a crucial role in eliciting the cell mechanisms underlying preconditioning; A2A receptors are not involved in this phenomenon, whereas A3 receptor activation is harmful to ischemic preconditioning.  相似文献   
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Acetylcholine (ACh) levels were determined in the brain of rats killed by decapitation or focussed microwave radiation during drug-induced convulsions. During metrazol or strychnine-induced convulsions a diffuse decrease in ACh levels was found in rats killed by decapitation. When the rats were killed by radiation and the brain was only divided into three large regions, strychnine caused no changes in ACh levels; metrazol caused a decrease in the cerebral cortex and lower brainstem. When discrete brain regions were investigated in rats killed by radiation, metrazol-induced convulsions were associated with a decrease in ACh level in all regions dissected and strychnine-induced convulsions with a decrease in the hippocampus and caudate nucleus only. Picrotoxin-induced convulsions were associated with a decrease in ACh level in the cerebral cortex, hippocampus, midbrain and medullapons, those induced by bicuculline with an increase in ACh level in the frontal cortex, hippocampus, midbrain and medulla-pons, by dimefline with an increase in the frontal cortex, midbrain and medulla-pons and a decrease in the caudate nucleus. The experiments show that each type of convulsant affects ACh levels in discrete brain regions in a different way.  相似文献   
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AIMS: Recent data suggest that the administration of bone marrow-derived stem cells (BMSC) might improve myocardial perfusion and left ventricular (LV) function after acute myocardial infarction (AMI). The aim of this study was to assess spontaneous mobilization of BMSC expressing the haematopoietic and endothelial progenitor cell-associated antigen CD34+ after AMI and its relation to post-infarction remodelling. METHODS AND RESULTS: Peripheral blood concentration of CD34+ BMSC was measured by flow cytometry in 54 patients with AMI, 26 patients with chronic stable angina (CSA), and 43 normal healthy subjects. In patients with AMI, LV function was measured by 2D-echocardiography. Eighteen AMI patients were reassessed at 1 year. BMSC concentration was higher in patients with AMI (mean peak value: 7.04+/-6.27 cells/microL), than in patients with CSA (3.80+/-2.12 cells/microL, P=0.036) and in healthy controls (1.87+/-1.52 cells/microL, P<0.001). At multivariable analysis statin use (P<0.001), primary percutaneous intervention (P=0.048) and anterior AMI (P=0.05) were the only independent predictors of increased BMSC mobilization after AMI. In the 28 patients without subsequent acute coronary events reassessed at 1 year follow-up, CD34+ cell concentration was an independent predictor of global and regional improvement of LV function (r=0.52, P=0.004 and r=-0.41, P=0.03, respectively). CONCLUSION: AMI is followed by enhanced spontaneous mobilization of BMSC, in particular, in patients on statin therapy and following a primary percutaneous intervention. More importantly persistent spontaneous mobilization of BMSC might contribute to determine a more favourable post-AMI remodelling.  相似文献   
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BACKGROUND: Earlier studies on the influence of pregnancy and postpartum period on the course of panic disorder have been inconsistent. The present study aims to quantify panic manifestations in these periods in large sample of women. METHOD: Panic manifestations, including exacerbations and new manifestations of panic disorder, were assessed retrospectively in a sample of 128 women with panic disorder with or without agoraphobia, 93 of whom had had 195 pregnancies. RESULTS: Panic manifestations were fewer during pregnancy and more frequent in the postpartum period when compared with the control period. Women who had never been pregnant had significantly more panic manifestations than women with prior pregnancies. Breastfeeding and miscarriages did not have a significant effect. Women with postpartum panic reported more psychosocial stress events during this period. CONCLUSIONS: Possible reasons for postpartum panic and the protective effects of pregnancy are discussed, including psychosocial or hormonal factors and other neurobiological changes. Postpartum panic coincides with a sudden drop of hormones after delivery.  相似文献   
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Bone marrow-derived human mesenchymal stem cells (hMSCs) have the potential to differentiate into several cell lines. Extracellular adenosine 5'-triphosphate (ATP) acts as a potent signaling molecule mediating cell-to-cell communication. Particular interest has been focused in recent years on the role of ATP in stem cell proliferation and differentiation. In the present work, we demonstrate that hMSCs at early stages of culture (P0-P5) spontaneously release ATP, which decreases cell proliferation. Increased hMSC proliferation is induced by the unselective P2 antagonist pyridoxalphosphate-6-azophenyl-2',4'-disulfonate (PPADS) and by the selective P2Y1 antagonist 2'-deoxy-N6-methyladenosine3',5'-bisphosphate (MRS 2179). A functional role of extracellular ATP in modulating ionic conductances with the whole-cell and/or perforated patch-clamp techniques was also investigated. Exogenous ATP increased both the voltage-sensitive outward and inward currents in 47% of cells, whereas, in 31% of cells, only an increase in inward currents was found. Cells responding in this dual manner to ATP presented different resting membrane potentials. Both ATP-induced effects had varying sensitivity to the P2 antagonists PPADS and MRS 2179. Outward ATP-sensitive currents are carried by potassium ions, since they are blocked by cesium replacement and are Ca2+ -dependent because they are eliminated in the presence of 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid. On the basis of different electrophysiological and pharmacological characteristics, we conclude that outward ATP-sensitive currents are due to Ca2+ -dependent K+ -channel activation following stimulation of P2Y receptors, whereas inward ATP-sensitive currents are mediated by P2X receptor activation. In summary, ATP released in early life stages of hMSCs modulates their proliferation rate and likely acts as one of the early factors determining their cell fate. Disclosure of potential conflicts of interest is found at the end of this article.  相似文献   
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