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41.
42.
We studied how nicotinic acetylcholine receptors (nAChRs) regulate glutamate release in the secondary motor area (Fr2) of the dorsomedial murine prefrontal cortex, in the presence of steady agonist levels. Fr2 mediates response to behavioral situations that require immediate attention and is a candidate for generating seizures in the frontal epilepsies caused by mutant nAChRs. Morphological analysis showed a peculiar chemoarchitecture and laminar distribution of pyramidal cells and interneurons. Tonic application of 5 µM nicotine on Layer V pyramidal neurons strongly increased the frequency of spontaneous glutamatergic excitatory postsynaptic currents. The effect was inhibited by 1 µM dihydro‐β‐erythroidine (which blocks α4‐containing nAChRs) but not by 10 nM methyllicaconitine (which blocks α7‐containing receptors). Excitatory postsynaptic currents s were also stimulated by 5‐iodo‐3‐[2(S)‐azetidinylmethoxy]pyridine, selective for β2‐containing receptors, in a dihydro‐β‐erythroidine ‐sensitive way. We next studied the association of α4 with different populations of glutamatergic terminals, by using as markers the vesicular glutamate transporter type (VGLUT) 1 for corticocortical synapses and VGLUT2 for thalamocortical projecting fibers. Immunoblots showed higher expression of α4 in Fr2, as compared with the somatosensory cortex. Immunofluorescence showed intense VGLUT1 staining throughout the cortical layers, whereas VGLUT2 immunoreactivity displayed a more distinct laminar distribution. In Layer V, colocalization of α4 nAChR subunit with both VGLUT1 and VGLUT2 was considerably stronger in Fr2 than in somatosensory cortex. Thus, in Fr2, α4β2 nAChRs are expressed in both intrinsic and extrinsic glutamatergic terminals and give a major contribution to control glutamate release in Layer V, in the presence of tonic agonist levels. Synapse 00:000–000, 2013 . © 2013 Wiley Periodicals, Inc.  相似文献   
43.
Glassy cell carcinomas are composed of malignant cells showing a "ground glass" cytoplasm, distinct cell membranes, and large nuclei with prominent nucleoli. To our knowledge, only 12 cases of glassy cell endometrial carcinomas (EGCC) have been reported until now. A 63-year-old patient complaining of irregular vaginal bleeding underwent hysteroscopy-guided biopsy revealing a well-differentiated endometrial endometrioid adenocarcinoma. The patient underwent left salpingo-oophorectomy, total abdominal hysterectomy, and pelvic lymphadenectomy. The final diagnosis was FIGO stage IB poorly differentiated endometrial adenosquamous carcinoma with > 90% of glassy tumor cells. The patient is alive, with no evidence of disease for 69 months after diagnosis. We describe an additional case of EGCC and review the data of the literature, emphasizing the need to strictly define the criteria for the diagnosis and the potential usefulness of assessing biologic parameters for the prognostic characterization of this rare entity.  相似文献   
44.
The cognitive characteristics of highly hypnotizable subjects (Highs) allow them to easily modify their cognitive and autonomic state. Under hypnosis, Highs receiving cognitive, fear-like stimulation exhibit the cardiovascular changes typical of fear/stress, but also show an EEG pattern indicating a balance between fear-induced arousal and hypnotic relaxation. Indeed, hypnosis is effective in the attenuation of both emotional experience and behaviour (emotional numbing). The aim of the present experiment was to investigate the possible different role of relaxation and suggestion in hypnotic emotional numbing. Tonic skin conductance, respirogram, heart rate, systolic and diastolic blood pressure were recorded in 3 groups of hypnotized subjects: Group 1 received a fearful guided imagery associated with threat suggestions (Threat) followed by the same fearful suggestion associated with numbing instructions (relaxation and "No-Threat"); Group 2 received the same instructions in the opposite order of presentation; Group 3 received the fearful suggestion with threat instructions twice. The numbing suggestion reduced fear-related emotional experience and autonomic responses; if No-Threat preceded Threat, the heart rate, heart rate variability and blood pressure were also reduced during Threat, in spite of self reports of high negative emotion. Thus, 1) the subjective experience and the autonomic response to fear can be dissociated; 2) the efficacy of numbing suggestion is extended to a subsequent Threat stimulation; 3) habituation does not contribute to the numbing effect. The results indicate that the specific numbing suggestion is the main factor in hypnotic modulation of the experience of fear.  相似文献   
45.
Postural control in subjects with high (Highs) and low (Lows) susceptibility to hypnosis is differentially affected by changes in visual and neck tactile/proprioceptive input. The aim of the present experiment was to investigate whether imagery of the visual and tactile sensory modalities also induces different modulation of postural control in Highs and Lows. Fourteen Highs and 16 Lows were included in the study; they were recorded while standing upright with eyes closed during visual and tactile imagery tasks and during mental computation. Their posture and movement were recorded with an Elite System and their experience was assessed after each task in a structured interview. Visual imagery was judged “easier” than tactile imagery by Lows, while Highs performed both tasks easily and judged the tactile imagery less effortful and more vivid than Lows. No difference was observed for the mental computation. The Highs’ body sway was not affected by the cognitive tasks, while Lows showed a task-related modulation of body sway. The results are in line with the hypothesis of lower vulnerability of Highs to the effects of tasks interfering with postural control and of different sensory-motor integration in Highs and Lows.  相似文献   
46.
Fatigue is usually defined as the point at which a particular level of force can be no longer maintained. In the present study, surface EMG of the masseter and temporalis anterior muscles was measured in ten healthy young adults performing a unilateral molar (right side) clench. The subjects clenched on a bite force transducer at a fixed force level of 13 kg (127 N) as long as they could (endurance). The test ended when the subjects could no longer produce the required bite force. From the EMG recordings, the median power frequency was calculated at the beginning of the task (T0), after one minute of clenching (T1), and at the end of the task (T2, endurance time). For each subject and muscle, percentage decrements in the median power frequency were also computed at T1 and T2. Endurance time ranged between 79 and 470 s. Significant modifications in the median power frequency in both masseter muscles (right side, p=0.003; left side, p=0.02, analysis of variance) were found, with a significant difference for the median frequency at T2 (p<0.02 at post hoc test). The modifications in the temporalis muscles were not significant (p>0.05). Additionally, at T1, significant percentage decrements in the median power frequency were found for both right side muscles (p<0.05, paired Student's ). The left side muscles modifications (p>0.05) were not significant. A significant effect of side was found (p=0.007, analysis of variance), without effects of muscle and no muscle x side interaction. At T2, both masseter muscles and the right side temporalis had a significant modification in their median power frequency. Overall, the modifications were larger in the masseter than in the temporalis muscles (p=0.022, analysis of variance), without effects of side and no muscle x side interaction. In conclusion, a fixed submaximal muscular contraction provoked fatigue modifications in the EMG power spectra that were well comparable to those obtained in previous investigations using forces computed as percentages of individually assessed maximum bite forces The present protocol (endurance clenching at a fixed force level) could be used as both a research and a clinical tool that would allow an easier and less troublesome assessment of both healthy persons and patients.  相似文献   
47.
The aim of the present study was to evaluate model identifiability when minimal physiologically-based pharmacokinetic (mPBPK) models are integrated with target mediated drug disposition (TMDD) models in the tissue compartment. Three quasi-steady-state (QSS) approximations of TMDD dynamics were explored: on (a) antibody-target complex, (b) free target, and (c) free antibody concentrations in tissue. The effects of the QSS approximations were assessed via simulations, taking as reference the mPBPK-TMDD model with no simplifications. Approximation (a) did not affect model-derived concentrations, while with the inclusion of approximation (b) or (c), target concentration profiles alone, or both drug and target concentration profiles respectively deviated from the reference model profiles. A local sensitivity analysis was performed, highlighting the potential importance of sampling in the terminal pharmacokinetic phase and of collecting target concentration data. The a priori and a posteriori identifiability of the mPBPK-TMDD models were investigated under different experimental scenarios and designs. The reference model and QSS approximation (a) on antibody-target complex were both found to be a priori identifiable in all scenarios, while under the further inclusion of QSS approximation (b) target concentration data were needed for a priori identifiability to be preserved. The property could not be assessed for the model including all three QSS approximations. A posteriori identifiability issues were detected for all models, although improvement was observed when appropriate sampling and dose range were selected. In conclusion, this work provides a theoretical framework for the assessment of key properties of mathematical models before their experimental application. Attention should be paid when applying integrated mPBPK-TMDD models, as identifiability issues do exist, especially when rich study designs are not feasible.  相似文献   
48.
The genus Pestivirus comprises globally distributed members of the family Flaviviridae, which cause severe losses in livestock. The most common species of the genus are bovine viral diarrhoea virus type 1 (BVDV‐1) and type 2 (BVDV‐2), classical swine fever virus (CSFV) and border disease virus (BDV). Recently, a novel ovine pestivirus was repeatedly detected in aborted lamb foetuses on a farm located in the Brescia Province (Italy). Complete genome characterization of this isolate showed that it was highly divergent from known pestivirus species and that it was genetically closely related to CSFV. The aim of this study was to determine the serological relatedness between the identified novel pestivirus and BVDV, BDV and CSFV selected strains for which homologous serum was available, by antigenic characterization performed using cross‐neutralization assays. The serological relatedness was expressed as the coefficient of antigenic similarity (R). Both field and specific antisera raised against the ovine pestivirus neutralized the CSFV reference strain Diepholz with titres significantly higher than those specific for the BDV and BVDV strains. Furthermore, the calculated R values clearly indicated that the novel ovine pestivirus is antigenically more related to CSFV than to ruminant pestiviruses, in agreement with the results of the genomic analysis. This would have severe consequences on CSFV serology in the event of a switch to porcine hosts with implications for CSFV surveillance and porcine health management.  相似文献   
49.
Since 2006, the foam replica method has been commonly recognized as a valuable technology for the production of highly porous bioactive glass scaffolds showing three-dimensional, open-cell structures closely mimicking that of natural trabecular bone. Despite this, there are important drawbacks making the usage of foam-replicated glass scaffolds a difficult achievement in clinical practice; among these, certainly the high operator-dependency of the overall manufacturing process is one of the most crucial, limiting the scalability to industrial production and, thus, the spread of foam-replicated synthetic bone substitutes for effective use in routine management of bone defect. The present review opens a window on the versatile world of the foam replica technique, focusing the dissertation on scaffold properties analyzed in relation to various processing parameters, in order to better understand which are the real issues behind the bottleneck that still puts this technology on the Olympus of the most used techniques in laboratory practice, without moving, unfortunately, to a more concrete application. Specifically, scaffold morphology, mechanical and mass transport properties will be reviewed in detail, considering the various templates proposed till now by several research groups all over the world. In the end, a comprehensive overview of in vivo studies on bioactive glass foams will be provided, in order to put an emphasis on scaffold performances in a complex three-dimensional environment.  相似文献   
50.
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