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971.
This case study of a 15-year-old boy diagnosed with bipolar affective disorder considers some of the biological, psychological, social and familial factors that precipitated and perpetuated his mental health problems. His mental health difficulties are considered using anti-psychiatry theories to take into account that his family's construction of "normal" would be considered pathological by others. The impact of labelling a person as a "difficult" client is examined and staff's attitudes (and subsequent behaviour) towards such service users are considered. Despite his immersion in a world of "madness" this young person managed to use the therapeutic interventions that were offered to him in an adolescent unit and he emerged from his mania remarkably intact. The impact of parental mental illness on children and young people is discussed in this case study and some recommendations are made for future practice.  相似文献   
972.
The purpose of this study was to evaluate the effectiveness of an automatic manual wheelchair braking system in the reduction of falls for patients at high risk of falls while transferring to and from a manual wheelchair. The study design was a normative survey carried out through the use of a written questionnaire sent to 60 skilled nursing facilities to collect data from the medical charts, which identified patients at high risk for falls who used an automatic wheelchair braking system. The facilities participating in the study identified a frequency of falls of high-risk patients while transferring to and from the wheelchair ranging from 2 to 10 per year, with a median fall rate per facility of 4 falls. One year after the installation of the automatic wheelchair braking system, participating facilities demonstrated a reduction of zero to three falls during transfers by high-risk patients, with a median fall rate of zero falls. This represents a statistically significant reduction of 78% in the fall rate of high-risk patients while transferring to and from the wheelchair, t (18) = 6.39, p < .0001. Incident reports of falls to and from manual wheelchairs were reviewed retrospectively for a 1-year period. This study suggests that high-risk fallers transferring to or from manual wheelchairs sustained significantly fewer falls when the Steddy Mate automatic braking system for manual wheelchairs was installed. The application of the automatic braking system allows clients, families/caregivers, and facility personnel an increased safety factor for the reduction of falls from the wheelchair.  相似文献   
973.
Combining EEG and fMRI to investigate the post-movement beta rebound   总被引:2,自引:0,他引:2  
The relationship between synchronous neuronal activity as measured with EEG and the blood oxygenation level dependent (BOLD) signal as measured during fMRI is not clear. This work investigates the relationship by combining EEG and fMRI measures of the strong increase in beta frequency power following movement, the so-called post-movement beta rebound (PMBR). The time course of the PMBR, as measured by EEG, was included as a regressor in the fMRI analysis, allowing identification of a region of associated BOLD signal increase in the sensorimotor cortex, with the most significant region in the post-central sulcus. The increase in the BOLD signal suggests that the number of active neurons and/or their synaptic rate is increased during the PMBR. The duration of the BOLD response curve in the PMBR region is significantly longer than in the activated motor region, and is well fitted by a model including both motor and PMBR regressors. An intersubject correlation between the BOLD signal amplitude associated with the PMBR regressor and the PMBR strength as measured with EEG provides further evidence that this region is a source of the PMBR. There is a strong intra-subject correlation between the BOLD signal amplitude in the sensorimotor cortex during movement and the PMBR strength as measured by EEG, suggesting either that the motor activity itself, or somatosensory inputs associated with the motor activity, influence the PMBR. This work provides further evidence for a BOLD signal change associated with changes in neuronal synchrony, so opening up the possibility of studying other event-related oscillatory changes using fMRI.  相似文献   
974.
The goal of this study was to identify recurrent regions of genomic gain or loss in giant-cell tumor of bone (GCTb). Array comparative genomic hybridization (aCGH) was performed for 20 frozen tumor samples of GCTb. A separate subset of 59 GCTb with outcome data was used for validation. The most frequent region of change identified by aCGH was gain of a 1-Mbp region at 20q11.1. In the validation arm of 59 cases the minimal common region of copy number gain at 20q11.1, seen in 54% of the samples, was BAC clone RP11-4O9, which contained the genes TPX2 and BCL2L1. For most cases, amplification was restricted to the mononuclear component and was not present in the multinucleated giant cells. Southern blot for TPX2 and BCL2L1 identified the former as the gene with the highest level of amplification for these two proposed candidate genes of importance. Immunohistochemistry for TPX2 expression correlated with amplification, while BCL2L1 expression was not identified. Kaplan-Meier curves for progression-free survival showed a statistically significant difference for cases with 20q11.1 amplification (P = 0.0001). Univariate analysis involving Cox proportional hazards models did not show a significant difference for initial treatment type (curettage versus resection) (P = 0.575), age (50) (P = 0.543), or sex (P = 0.268), but did correlate with 20q11.1 amplification (P = 0.001). By multivariate analysis, it was found that 20q11.1 amplification (P = 0.001) was the only factor to reach statistical significance. 20q11.1 amplification can be used as a marker of prognostic importance in GCTb. We propose TPX2 as a candidate oncogene in the core-amplified region at 20q11.1.  相似文献   
975.
We report the application of the Laguerre deconvolution technique (LDT) to the analysis of in-vivo time-resolved laser-induced fluorescence spectroscopy (TR-LIFS) data and the diagnosis of atherosclerotic plaques. TR-LIFS measurements were obtained in vivo from normal and atherosclerotic aortas (eight rabbits, 73 areas), and subsequently analyzed using LDT. Spectral and time-resolved features were used to develop four classification algorithms: linear discriminant analysis (LDA), stepwise LDA (SLDA), principal component analysis (PCA), and artificial neural network (ANN). Accurate deconvolution of TR-LIFS in-vivo measurements from normal and atherosclerotic arteries was provided by LDT. The derived Laguerre expansion coefficients reflected changes in the arterial biochemical composition, and provided a means to discriminate lesions rich in macrophages with high sensitivity (>85%) and specificity (>95%). Classification algorithms (SLDA and PCA) using a selected number of features with maximum discriminating power provided the best performance. This study demonstrates the potential of the LDT for in-vivo tissue diagnosis, and specifically for the detection of macrophages infiltration in atherosclerotic lesions, a key marker of plaque vulnerability.  相似文献   
976.
977.
978.
OBJECTIVE: To develop a measure of home and community participation related to the World Health Organization's International Classification of Functioning, Disability and Health. DESIGN: Cross-sectional analysis of survey data. SETTING: Nine medical inpatient rehabilitation facilities from 6 states. PARTICIPANTS: A total of 594 patients of mixed impairment type admitted for inpatient rehabilitation in 2002. Mean age was 74.0 years and 61.4% were women. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Reliability and validity of the participation instrument. RESULTS: A 20-item instrument of home and community participation was developed (PAR-PRO). The instrument showed good internal consistency and good Rasch person and item fit statistics. Four subfactors were identified beyond the unidimensional construct of participation including domestic management, socialization, physical vigor, and generative activities. The PAR-PRO total participation score correlated inversely with age (r=-.31, P<.001) but did not differ by sex. CONCLUSIONS: The 20-item PAR-PRO instrument of home and community participation displayed good psychometric characteristics. The instrument shows promise as a broad measure of home and community involvement for persons with disabilities. Further work is needed to support its application for people without disability.  相似文献   
979.
BACKGROUND: Cyanide (CN) is a lethal toxin. Quantification in blood is necessary to indicate exposure from many sources, including food, combustion byproducts, and terrorist activity. We describe an automated procedure based on isotope-dilution gas chromatography-mass spectrometry (ID GC/MS) for the accurate and rapid determination of CN in whole blood. METHODS: A known amount of isotopically labeled potassium cyanide (K13C15N) was added to 0.5 g of whole blood in a headspace vial. Hydrogen cyanide was generated through the addition of phosphoric acid, and after a 5-min incubation, 0.5 mL of the headspace was injected into the GC/MS at an oven temperature of -15 degrees C. The peak areas from the sample, 1H12C14N+, at m/z 27, and the internal standard, 1H13C15N+, at m/z 29, were measured, and the CN concentration was quantified by ID. The analysis time was 15 min for a single injection. RESULTS: We demonstrated method accuracy by measuring the CN content of unfrozen whole blood samples fortified with a known amount of CN. Intermediate precision was demonstrated by periodic analyses over a 14-month span. Relative expanded uncertainties based on a 95% level of confidence with a coverage factor of 2 at CN concentrations of 0.06, 0.6, and 1.5 microg/g were 8.3%, 5.4%, and 5.3%, respectively. The mean deviation from the known value for all concentrations was <4%. CONCLUSION: The automated ID GC/MS method can accurately and rapidly quantify nanogram per gram to microgram per gram concentrations of CN in blood.  相似文献   
980.
This study examined the extent of cuspal flexure caused by progressively larger cavity preparations, including endodontic access, and progressive simulated occlusal loading with 50N, 100N and 150N. Ten intact extracted maxillary premolars were embedded in acrylic resin, and a small ball was attached to each cuspal tip as a reference point for intercuspal distance measurements. The teeth were subjected sequentially to the following procedures: conservative MO cavity preparation, extensive MO cavity preparation, endodontic access step and MOD cavity preparation. After each cavity preparation procedure, the specimens were subjected to increasing loads of 50, 100 and 150 N, and the intercuspal distance was recorded by means of a digital caliper. The extension of cavity preparation and the magnitude of occlusal load significantly influenced cuspal deflection. After 50 and 100 N loading, a similar cuspal deflection was exhibited by conservative and extensive MO preparations with or without the endodontic access step. With 150 N loading, the endodontic access step was related to a statistically larger cuspal deflection versus the deflection recorded for conservative and extensive MO preparations. The removal of both marginal ridges in MOD cavity preparation with endodontic access produced a dramatic increase in cuspal deflection for the three loads tested.  相似文献   
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