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1.
BACKGROUND: In 1992 France set up a national cystic fibrosis observatory (Observatoire national de la mucoviscidose, ONM) to monitor the state of health of patients on an annual basis. Using the ONM data, this study estimates the main indicators for life expectancy and assesses the total number of cystic fibrosis patients. METHODS: The data for the years 1994 to 2003 are divided into 3-year periods. Life tables are drawn up for these periods, from which mean and median lengths of life are determined. Using the most recent life table, the number of births in 2003 and the incidence of the disease, the total population of patients can be estimated, assuming a stationary population. RESULTS: In 2001-2003, life expectancy at birth of patients registered with the ONM was 39.1 years and median length of life was 36.4 years. These results, substantially better than those of 1994-1996, are linked to improved conditions of patient inclusion in the ONM database, to improvements in their healthcare, but also to the limitations of the life tables. Based on the 2003 data, the total theoretical number of patients is 6490, and coverage by the ONM database is thus 63.2%. CONCLUSIONS: These provisional results demonstrate the need to convert the ONM observatory into a registry providing exhaustive coverage of all patients.  相似文献   
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The effect of experimentally induced seizure activity on the functional reorganization of motor maps has not previously been investigated. Furthermore, while the functional reorganization of motor maps has been thought to involve increases in synaptic communication, there has yet to be a test of this hypothesis. Here we show that repeated seizure activity (kindling), that is accompanied by increased synaptic strength within adult rat motor cortex, results in a doubling of the caudal forelimb motor area. We measured neo-cortical evoked potentials in the right hemisphere prior to 25 days of electrical kindling of the medial frontal corpus callosum or amygdala and re-measured them either 1 or 21 days following the last kindling session. Then, using high resolution intracortical microstimulation (ICMS), the caudal forelimb area in the left hemisphere was mapped. This is the first report of any procedure causing a motor representation to double in size. Furthermore, this expansion was related to the enhanced area of a neocortical polysynaptic field potential and not the motor convulsions per se. Moreover, both the motor map and field potential enhancements were persistent in nature and could be driven from either cortical or limbic sites. The data have implications for human populations with epilepsy.  相似文献   
4.
The mismatch negativity (MMN) component of auditory event-related brain potentials can be used as a probe to study the representation of sounds in auditory sensory memory (ASM). Yet it has been shown that an auditory MMN can also be elicited by an illusory auditory deviance induced by visual changes. This suggests that some visual information may be encoded in ASM and is accessible to the auditory MMN process. It is not known, however, whether visual information affects ASM representation for any audiovisual event or whether this phenomenon is limited to specific domains in which strong audiovisual illusions occur. To highlight this issue, we have compared the topographies of MMNs elicited by non-speech audiovisual stimuli deviating from audiovisual standards on the visual, the auditory, or both dimensions. Contrary to what occurs with audiovisual illusions, each unimodal deviant elicited sensory-specific MMNs, and the MMN to audiovisual deviants included both sensory components. The visual MMN was, however, different from a genuine visual MMN obtained in a visual-only control oddball paradigm, suggesting that auditory and visual information interacts before the MMN process occurs. Furthermore, the MMN to audiovisual deviants was significantly different from the sum of the two sensory-specific MMNs, showing that the processes of visual and auditory change detection are not completely independent.  相似文献   
5.
A genome-wide scan for asthma phenotypes was conducted in the whole sample of 295 EGEA families selected through at least one asthmatic subject. In addition to asthma, seven phenotypes involved in the main asthma physiopathological pathways were considered: SPT (positive skin prick test response to at least one of 11 allergens), SPTQ score being the number of positive skin test responses to 11 allergens, Phadiatop (positive specific IgE response to a mixture of allergens), total IgE levels, eosinophils, bronchial responsiveness (BR) to methacholine challenge and %predicted FEV(1). Four regions showed evidence for linkage (P相似文献   
6.
Allergic reactions are triggered via crosslinking of the high-affinity receptor for immunoglobulin E, F(c)epsilonRI. In humans, F(c)epsilonRI is expressed as a tetramer (alphabetagamma(2)) and a trimer (alphagamma(2)). The beta subunit is an amplifier of F(c)epsilonRI surface expression and signaling. Here, we show that as a consequence of alternative splicing, the F(c)epsilonRIbeta gene encodes two proteins with opposing and competing functions. One isoform is the full-length classical beta, the other a novel truncated form, beta(T). In contrast to beta, beta(T) prevents F(c)epsilonRI surface expression by inhibiting alpha chain maturation. Moreover, beta(T) competes with beta to control F(c)epsilonRI surface expression in vitro. We propose that the relative abundance of the products of the beta gene may control the level of F(c)epsilonRI surface expression and thereby influence susceptibility to allergic diseases.  相似文献   
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This study tried to differentiate the consequences of chronic hypoxia on the electrophysiological and physiological properties and the histological characteristics of slow and fast muscles in rats. Animals inhaled a 10% O2 concentration for a 1-month period. Then, slow [soleus (SOL)] and fast [extensor digitorum longus (EDL)] muscles were analyzed in vitro by physiological and electrophysiological measurements and histological analyses. The results were compared to those obtained in corresponding muscles of an age-matched normoxic group. After exposure to hypoxia: (1) in SOL, there was a tendency to elevated Fmax, a significant increase in twitch force and tetanic frequency and a shortening of M-wave duration, and a reduced percentage of type I fibres, whereas the proportion of type IIa fibres doubled; (2) in EDL, Fmax and tetanic frequency were lowered, the muscle became less resistant to fatigue, and the proportion of type IId/x fibres was halved. Then, after 1 month of hypoxia, in the SOL muscle, both the contractile and histological properties resemble those of a fast muscle. By contrast, the EDL became slower, despite its histology was modestly affected. Reduced muscle use in hypoxia could explain the tendency for deteriorating adaptations in EDL, and the faster properties of SOL could result from hypoxia-induced inhibition of the growth-related fast-to-slow shift in muscle fibre types.  相似文献   
8.
In a previous study we demonstrated that MG-63 cells cultured on Ti-6Al-4V discs covered by alumina ceramic and submitted to intermittent mechanical strain (IMS) presented morphological alteration associated with enhanced differentiation. Here we examine how the mechanical response of osteoblasts can be modulated by the nature of the substrate. MG-63 cells were cultured on four materials: polystyrene and Ti-6Al-4V (average roughness = 0.48 microm) as smooth substrates; Ti-6Al-4V (average roughness = 5.76 microm) and Ti-6Al-4V covered with alumina (average roughness = 5.21 microm) as rough substrates. Mechanical strains were applied for 15 min, three times a day for 1-5 days with a 600 microstrains magnitude and a 0.25 Hz frequency. IMS stimulated alkaline phosphatase activity by 25-35% on all substrates and had no effect on cell growth on either substrate. Fibronectin (FN) was chosen as representative of cell-matrix interaction. FN production was increased by 60% after 1 day of stretching only on alumina-coated discs. FN organization examined on smooth substrates was affected by 5 days of IMS, showing a thickening of the fibres. The same modifications induced by IMS were previously observed on alumina-covered discs. Vinculin expression was not affected by IMS whatever the substrate. Cell-cell interactions were determined by N-cadherin immunoblotting. N-cadherin expression was increased by IMS specifically on rough substrates. Our results suggest that the nature of the surface did not influence the up-regulation of alkaline phosphatase activity induced by IMS, but modulates specifically cell-substrate as well as cell-cell interactions in response to IMS.  相似文献   
9.
BACKGROUND: Cytomegalovirus (CMV) remains a major opportunistic agent among transplant recipients. While detection of CMV pp65-lower matrix protein (pp65Ag) is still widely used for monitoring CMV infection, real-time PCR assays have been recently developed for routine quantitation of CMV DNA. However, correlations are lacking between results of pp65Ag and quantitative PCR assays and there is no consensus yet as to the more appropriate blood compartment (whole blood (WB), leukocytes, plasma) to be tested with PCR assays. OBJECTIVES: The aims of the study were to determine, in a population of transplant recipients: (i) the correlation between pp65Ag and CMV quantitative real-time PCR in our setting and (ii) the utility of plasma CMV DNA quantitation in comparison to WB quantitation. METHODS: In 170 blood samples (from 61 solid organ or bone marrow transplant recipients) with pp65Ag results, CMV quantitation was performed in WB and plasma using an in-house real-time quantitative PCR. RESULTS: Real-time PCR and pp65Ag results in WB were correlated: thresholds of 10 and 50(+) cells/200,000 cells were equivalent to 3.3 log(10)copies/mL (2,000 copies/mL) and 3.8 log(10)copies/mL (6,300 copies/mL), respectively. When WB viral load was >or=3.6 log(10)copies/mL, the risk to have a negative plasma CMV DNA result was 相似文献   
10.
The effects of manipulating central serotonergic transmission were assessed on the anti-punishment effects of diazepam (2 mg/kg IP) in rats. In a paradigm involving the inhibition of pressing for food induced by the delivery of a signal previously associated with electric foot-shocks, lesioning serotonergic neurons of the dorsal raphé with the neurotoxin 5,7-dihydroxytryptamine (5,7-DHT; 1 g in 0.4 l) neither affected behavioral inhibition in control rats nor modified the ability of diazepam to release responding. Furthermore, suppression of pressing for food induced by a fixed ratio 7 schedule of shock presentation was reduced by bilateral infusion of 5,7-DHT (2 g in 0.5 l) into the substantia nigra, but the ability of diazepam to increase punished responding was preserved. Finally, blockade of benzodiazepine-induced decrease in serotonin release by application of the benzodiazepine receptor antagonist Ro 15-1788 (10–5–10–4 M in 0.2 l) into the dorsal raphé did not alter the releasing effect of diazepam on suppression of pressing for food caused by a signal of punishment. At these concentrations. Ro 15-1788 was devoid of any effect on behavioral inhibition in control rats. Taken together, these results indicate that the anti-punishment activity of benzodiazepines can be dissociated from the reduction in tryptaminergic transmission produced by these drugs.  相似文献   
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