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51.
Estimated percentile ranks for Verbal, Performance, and Full Scale IQs are provided for the WAIS-R at six educational levels (N = 1,880). These tables are based on means and standard deviations from the standardization sample. Application of the tables is discussed, as are implications for clinical practice.  相似文献   
52.
Early life adversity exerts a detrimental influence on developing brain neuronal networks and its consequences may include mental health disorders. In rats, prenatal stress may lead to anxiety and depressive‐like behavior in the offspring. Several lines of evidence implicated an involvement of prenatal stress in alterations of the brain serotonergic system functions, but the effects of prenatal stress on its core, the dorsal raphe nucleus (DRN), still remain incompletely understood. The present study was aimed at finding whether prenatal stress induces modifications in the glutamatergic and GABAergic inputs to DRN projection cells and whether it affects DRN 5‐HT7 receptors, which modulate activity of these synapses. Prenatal stress resulted in an increase in basal frequency of spontaneous excitatory postsynaptic currents (sEPSCs) and in a decrease in basal frequency of spontaneous inhibitory postsynaptic currents (sIPSCs) recorded from putative projection neurons in DRN slices ex vivo. While there were no changes in the excitability of DRN projection neurons, the 5‐HT7 receptor‐mediated reduction in the sEPSC frequency and rise in the sIPSC frequency, seen in control rats, were largely absent in slices obtained from prenatally stressed rats. Repeated administration of SB 269970, a 5‐HT7 receptor antagonist, resulted in a reversal of prenatal stress‐induced alterations in 5‐HT7 receptor‐mediated effects on the sEPSC/sIPSC frequency. Moreover, the treatment reversed prenatal stress‐induced alterations in basal excitatory transmission and partially reversed the effect of stress on basal inhibitory transmission in the DRN.  相似文献   
53.
One of the many biological functions of nitric oxide is the ability to protect cells from oxidative stress. To investigate the potential contribution of low steady state levels of nitric oxide generated by endothelial nitric oxide synthase (eNOS) and the mechanisms of protection against H(2)O(2), spontaneously transformed human ECV304 cells, which normally do not express eNOS, were stably transfected with a green fluorescent-tagged eNOS cDNA. The eNOS-transfected cells were found to be resistant to injury and delayed death following a 2-h exposure to H(2)O(2) (50-150 microM). Inhibition of nitric oxide synthesis abolished the protective effect against H(2)O(2) exposure. The ability of nitric oxide to protect cells depended on the presence of respiring mitochondria as ECV304+eNOS cells with diminished mitochondria respiration (rho(-)) are injured to the same extent as nontransfected ECV304 cells and recovery of mitochondrial respiration restores the ability of nitric oxide to protect against H(2)O(2)-induced death. Nitric oxide also found to have a profound effect in cell metabolism, because ECV304+eNOS cells had lower steady state levels of ATP and higher utilization of glucose via the glycolytic pathway than ECV304 cells. However, the protective effect of nitric oxide against H(2)O(2) exposure is not reproduced in ECV304 cells after treatment with azide and oligomycin suggesting that the dynamic regulation of respiration by nitric oxide represent a critical and unrecognized primary line of defense against oxidative stress.  相似文献   
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Plasma lipids and osteoporosis in postmenopausal women   总被引:18,自引:0,他引:18  
Many clinical studies have shown that osteoporosis is associated with atherosclerosis and cardiovascular death. Although both high plasma levels of low density lipoprotein cholesterol (LDL-C) and low plasma levels of high density lipoprotein cholesterol (HDL-C) are known to be risk factors for atherosclerosis, it is unclear whether such lipid derangements are also associated with the pathogenesis of osteoporosis. In this study, we evaluated the relationships between plasma levels of total C, LDL-C, HDL-C, or triglyceride (TG) versus bone mineral density (BMD) at the lumbar spine, femoral neck, radius, or total body as well as the presence of vertebral fractures in 214 Japanese postmenopausal women (age range, 47-86 years, mean 62.7). Multiple regression analysis was performed between BMD at each skeletal site versus each lipid level adjusted for age, years after menopause, body mass index (BMI), and %fat. Plasma LDL-C levels were significantly and inversely correlated with the absolute values of both one-third radial (1/3R) and distal radial (UDR) BMD (p<0.01), and tended to be inversely correlated with the absolute values of L-BMD (p=0.051). In contrast, plasma HDL-C levels were significantly and positively correlated with the absolute values of L, 1/3R and UDR BMD (p<0.05). On the other hand, plasma TG levels were significantly lower in women with vertebral fractures than in those without fractures (97.0+/-36.5 vs. 126.4+/-65.8 mg/dl, mean+/-SD, p<0.05). When multivariate logistic regression analysis was performed with the presence of vertebral fractures as a dependent variable and each lipid level adjusted for age, years after menopause, BMI, and %fat as independent variables, TG alone was selected as an index affecting the presence of vertebral fractures (odds ratio: 0.51, 95% confidential interval: 0.29-0.89 per SD increase, p<0.05). Our study showed that plasma LDL-C and HDL-C levels were inversely and positively correlated with both R- and L-BMD values, respectively, while low plasma TG levels were associated with the presence of vertebral fractures in postmenopausal women. Thus, plasma lipids might be related to bone mass and bone fragility, and might be the common factor underlying both osteoporosis and atherosclerosis.  相似文献   
57.

Background/objectives

Pancreatic exocrine insufficiency (PEI) is commonly caused by chronic pancreatitis (CP) or cystic fibrosis (CF). There are no PEI-specific patient-reported assessments of symptoms and impacts. The PEI Questionnaire (PEI-Q) was developed through qualitative research with PEI patients and expert clinical input. This study evaluated the psychometric properties of the PEI-Q.

Methods

162 PEI patients (CF?=?71 and CP?=?91), 62 diarrhoea-specific irritable bowel syndrome (IBS-D) patients and 60 healthy controls completed the 26-item PEI-Q and the Gastrointestinal Quality of Life Index (GIQLI) at baseline. PEI patients completed the measures again two weeks later to assess the test-retest reliability of the PEI-Q. Analyses supported item reduction and scoring algorithm development, followed by psychometric evaluation.

Results

Over 90% of PEI patients completed at least 23 of the 26 items at baseline. Item responses and clinical relevance supported retention of 18 items. Factor analysis supported a three-factor solution (abdominal symptoms, bowel movements, impacts) with adequate model fit. PEI-Q scores had good internal consistency (Cronbach's alpha: 0.77–0.82) and test-retest reliability (ICC: 0.73–0.87). Correlations between PEI-Q and GIQLI supported convergent validity. Known-groups and receiver operating characteristic analyses demonstrated that PEI-Q scores discriminated (p?<?0.001) between differing PEI severities, and PEI patients and controls.

Conclusions

The PEI-Q has good validity and reliability. Results indicate that the PEI-Q could be used to aid identification and diagnosis of PEI, assist in the management of patients already diagnosed with PEI, ensuring correct and optimum treatment as well as enhance patient-clinician communication.  相似文献   
58.
Recombinant bacteriophage expressing Brucella abortus antigens have been isolated from a lambda gt11 expression library by using antibody raised against a sodium dodecyl sulfate-polyacrylamide gel electrophoresis-purified cell envelope protein of 36 kilodaltons. Fusion products expressed by these recombinants vary in apparent molecular mass by sodium dodecyl sulfate-polyacrylamide gel electrophoresis but only slightly exceed the size of beta-galactosidase. Western blot (immunoblot) analysis of crude lysates derived from lambda gt11 lysogens indicates that the fusion products react specifically with the original antisera used for recombinant selection and selectively bind antibody directed against the 36-kilodalton cell envelope protein. Analysis of the DNA inserts from 11 independently selected recombinants reveals similar-size EcoRI fragments which range in size from 150 to 300 base pairs (bp), all of which cross-hybridize via Southern blot analysis. Three independently selected EcoRI inserts ranging in size from 200 to 270 bp have been subcloned into M13mp18 and sequenced; all three contain a common region of about 200 bp. Southern blot analysis of B. abortus genomic DNAs digested with EcoRI, PstI, or DdeI indicates the presence of two fragments which hybridize to these DNA probes while single BamHI and HindIII fragments hybridize. The absence of these sites from the internal DNA sequence of the cloned probes suggests the presence of more than one copy of these sequences within the B. abortus genome. The same DNA probes have been used to select genomic clones of approximately 20 kbp from a lambda 2001 library. The lambda 2001 recombinants contain single BamHI fragments and two PstI fragments which hybridize to these oligonucleotide probe constructed on the basis of the amino-terminal sequence of the mature gene product hybridizes to the same BamHI and PstI fragments as the lambda gt11-derived DNA probe. Although the relative positions of the oligonucleotide sequences and the lambda gt11 insert within the genes is not known, the two sequences flank a region which corresponds to at least 40% of the size of the predicted gene. Additional experimentation must be performed to determine whether these sequences represent either two complete structural genes encoding major cell envelope proteins or repetitive sequences within a single structural gene.  相似文献   
59.
Fewell GD  Meredith M 《Brain research》2002,941(1-2):91-106
Chemosensory stimuli are essential for mating in male hamsters but either main olfactory or vomeronasal input is sufficient in sexually experienced males. Activation in central chemosensory pathways and medial preoptic area, after stimulation with female chemosignals or after mating, was estimated by counting neurons expressing Fos protein in experienced and naive males, with or without vomeronasal organ lesions. Regions counted included main and accessory olfactory bulbs, corticomedial amygdala, bed nucleus stria terminalis and medial preoptic area. Chemosensory stimulation was more effective in activating medial preoptic area in experienced than in naive males. In experienced males with vomeronasal organs removed, main olfactory input was as effective in activating medial preoptic area as was the combination of main and accessory input available to intact animals. As previously reported, the main olfactory input remaining after vomeronasal lesions in naive males was poorly effective in activating medial preoptic area, and these animals had impaired mating behavior. The change in access of chemosensory input to medial preoptic area after experience suggests that an experience-dependent synaptic modulation in this pathway, perhaps in the amygdala, may underlie some changes in mating behavior with experience.  相似文献   
60.
Alzheimer's disease (AD) is a complex and slowly progressing dementing disorder that results in neuronal and synaptic loss, deposition in brain of aberrantly folded proteins, and impairment of spatial and episodic memory. Most studies of mouse models of AD have employed analyses of cognitive status and assessment of amyloid burden, gliosis, and molecular pathology during disease progression. Here we sought to understand the behavioral, cellular, ultrastructural, and molecular changes that occur at a pathological stage equivalent to the early stages of human AD. We studied the TgCRND8 mouse, a model of aggressive AD amyloidosis, at an early stage of plaque pathology (3 months of age) in comparison to their wildtype littermates and assessed changes in cognition, neuron and spine structure, and expression of synaptic glutamate receptor proteins. We found that, at this age, TgCRND8 mice display substantial plaque deposition in the neocortex and hippocampus and impairment on cued and contextual memory tasks. Of particular interest, we also observed a significant decrease in the number of neurons in the hippocampus. Furthermore, analysis of CA1 neurons revealed significant changes in apical and basal dendritic spine types, as well as altered expression of GluN1 and GluA2 receptors. This change in molecular architecture within the hippocampus may reflect a rising representation of inherently less stable thin spine populations, which can cause cognitive decline. These changes, taken together with toxic insults from amyloid‐β protein, may underlie the observed neuronal loss. J. Comp. Neurol. 522:2319–2335, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   
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