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991.
We examined amyloid precursor protein (APP) surface expression on circulating leukocytes and in brain tissues from normal individuals and HIV+ subjects with cognitive impairment. Most monocytes, and a subset of B-lymphocytes, expressed APP, while T-lymphocytes, granulocytes, and natural killer (NK) cells did not. CD14bright/CD16+ monocytes expressed the highest levels, and CD14dim/CD16+ cells were negative, suggesting a relationship with activation. Higher APP+ monocyte levels correlated with increased numbers of CD16+ monocytes, but not with the degree of cognitive impairment. Treatment of monocytes with M-CSF, but not LPS, upregulated APP expression. In the brain, APP appeared as axonal immunoreactivity and diffuse plaques, and APP+ perivascular macrophages were seen in cases with severe dementia. APP may facilitate monocyte entry into the brain.  相似文献   
992.
993.
Background Despite the accumulated evidence on the efficacy of brief interventions in hazardous drinkers some ambiguity remains regarding their differential effectiveness by gender. Methods Meta‐analysis of independent studies conducted in primary health care settings with a follow‐up of 6–12 months which report results separately by gender. Two outcome measures were selected: the quantity of typical weekly alcohol consumption and the frequency of drinkers who reported consumption below hazardous levels after the intervention. Results Seven studies were included in the meta‐analysis. The standardized effect sizes for the reduction of alcohol consumption were similar in men (d =? 0.25; 95% CI = ? 0.34 to ?0.17) and women (d = ? 0.26; 95% CI = ? 0.38 to ? 0.13). The odds ratios (OR) for the frequency of individuals who drank below harmful levels were also similar (four studies; OR for men = 2.32; 95% CI = 1.78–2.93; OR for women = 2.31; 95% CI = 1.60–3.17). The difference between genders was negligible. Conclusion Our results support the equality of outcomes among men and women achieved by brief interventions for hazardous alcohol consumption in primary care settings.  相似文献   
994.
995.
A 28-year-old man presented with history of raised intracranial pressure and one episode of generalized tonic clonic seizures. Computed Tomogram revealed multiple contrast enhancing intracranial lesions. Biopsy of one of the lesions was reported as metastatic alveolar soft part sarcoma. He was advised whole brain radiotherapy.  相似文献   
996.
Berkowitz A 《Brain research》2004,1014(1-2):164-176
In limbed vertebrates, the capacity to generate rhythmic motor patterns for locomotion and scratching is distributed over spinal cord segments of the limb enlargement (e.g., lumbosacral segments), but within this region, rostral segments are more rhythmogenic than caudal segments. The underlying reasons for this rostrocaudal asymmetry are not clear. One possibility is that rostral and caudal segments receive distinct sets of propriospinal projections. To test this hypothesis, I injected horseradish peroxidase (HRP) into the ventral horn unilaterally in a rostral or caudal segment of the turtle hindlimb enlargement. I quantitatively assessed the distributions of retrogradely labeled neurons in six hindlimb enlargement and pre-enlargement segments. The cross-sectional distribution did not depend on which segment was injected. Ipsilateral labeling occurred predominantly in the deep dorsal horn, the lateral part of the intermediate zone, and the dorsal two-thirds of the ventral horn, while contralateral labeling occurred mainly in the medial part of the ventral horn and the lateral part of the intermediate zone. This cross-sectional distribution is similar to what has been seen in mammals. The rostrocaudal distribution of labeled cells, however, depended on which segment was injected. Rostral injections gave rise to rostrally skewed distributions, dominated by descending propriospinal neurons. Caudal injections gave rise to caudally skewed distributions, dominated by ascending propriospinal neurons. Thus, rostral segments of the hindlimb enlargement received more propriospinal inputs from immediately rostral than immediately caudal segments, while the reverse was true for inputs to caudal segments. This anatomical asymmetry may contribute to known functional asymmetries within the enlargement.  相似文献   
997.
Myoinositol abnormalities in temporal lobe epilepsy   总被引:1,自引:1,他引:0  
PURPOSE: This study used magnetic resonance spectroscopy (MRS) to examine metabolite abnormalities in the temporal and frontal lobe of patients with temporal lobe epilepsy (TLE) of differing severity. METHODS: We investigated myoinositol in TLE by using short-echo MRS in 34 TLE patients [26 late onset (LO-TLE), eight hippocampal sclerosis (HS-TLE)], and 16 controls. Single-voxel short-echo (35 ms) MR spectra of temporal and frontal lobes were acquired at 1.5 T and analyzed by using LCModel. RESULTS: The temporal lobe ipsilateral to seizure origin in HS-TLE, but not LO-TLE, had reduced N-acetylaspartate (NA) and elevated myoinositol (MI; HS-TLE NA, 7.8 +/- 1.9 mM, control NA, 9.2 +/- 1.3 mM; p < 0.05; HS-TLE MI, 6.1 +/- 1.6 mM, control mI 4.9 +/- 0.8 mM, p< 0.05). Frontal lobe MI was low in both patient groups (LO-TLE, 4.3 +/- 0.8 mM; p < 0.05; HS-TLE, 3.6 +/-.05 mM; p < 0.001; controls, 4.8 +/- 0.5 mM). Ipsilateral frontal lobes had lower MI (3.8 +/- 0.7 mM; p < 0.01) than contralateral frontal lobes (4.3 +/- 0.8 mM; p < 0.05). CONCLUSIONS: MI changes may distinguish between the seizure focus, where MI is increased, and areas of seizure spread where MI is decreased.  相似文献   
998.
OBJECTIVE: We performed spike triggered functional MRI (fMRI) in a 12 year old girl with Benign Epilepsy with Centro-temporal Spikes (BECTS) and left-sided spikes. Our aim was to demonstrate the cerebral origin of her interictal spikes. METHODS: EEG was recorded within the 3 Tesla MRI. Whole brain fMRI images were acquired, beginning 2-3 seconds after spikes. Baseline fMRI images were acquired when there were no spikes for 20 seconds. Image sets were compared with the Student's t-test. RESULTS: Ten spike and 20 baseline brain volumes were analysed. Focal activiation was seen in the inferior left sensorimotor cortex near the face area. The anterior cingulate was more active during baseline than spikes. CONCLUSIONS: Left sided epileptiform activity in this patient with BECTS is associated with fMRI activation in the left face region of the somatosensory cortex, which would be consistent with the facial sensorimotor involvement in BECT seizures. The presence of BOLD signal change in other regions raises the possibility that the scalp recorded field of this patient with BECTs may reflect electrical change in more than one brain region.  相似文献   
999.
Evoked play narratives have been demonstrated to provide a novel window towards internal emotion regulation and mental representations. The present study evaluates covariations between emotion themes and mother-child interaction, as well as child behavior problems. An exploratory study in non-referred children in the 3-6 age span utilizing the MacArthur-method was conducted by taking emotional, conflictive and moral themes as indices of emotion-regulatory processes. Emotion themes were linked to external measures of dyadic Emotional Availability, interparental relationship quality, and behavior problems employing the 4/18 version of the Child Behavior Checklist. Mental representations were aggregated using the Person Representation Coding System. Of a principal components analysis with subsequent varimax-rotation for narrative content codes resulted four emotion theme composites: social conflicting, a prosocial aggregate, an antisocial aggregate, and a composite conflict solving/-understanding. The 4-factor solution displayed meaningful correlation patterns with the mental representations of self and parents, as well as with most of the external measures. Although subsequent studies ought to be methodologically improved both in design and sample size, the results of the present investigation give rise to the assumption that future efforts of validating emotion-regulatory processes with more established outside measures are likely to be successful.  相似文献   
1000.
Most longitudinal studies on the relationship between psychosocial health resources and risks, and the employees' subsequent sickness absences have been conducted in the public sector. The purpose of this study was to find out psychosocial antecedents of sickness absenteeism in the private industrial sector. The effects of job characteristics (job autonomy and job complexity), physical and psychological symptoms, and social support (from coworkers and supervisors) on sickness absenteeism were investigated. The number of long (4-21 days) and very long (>21 days) sickness absence episodes of 3895 persons (76% men and 24% women, mean age 44 years) was obtained from the health registers of a multinational forest industry corporation in 1995-1998. A questionnaire survey on the working conditions and health of the workers was carried out in 1996. The follow-up time of the sickness absences was 1-year 9-month. Job autonomy was found to be associated with long and very long episodes in men (rate ratio (RR) in the lowest autonomy group approximately 2 times higher than the highest autonomy group), and with very long episodes of absence in women (2-3 times higher RR between the low vs. the high category). Low job complexity predicted men's very long absences (RR 1.4). Long and very long episodes were associated with physical and psychological symptoms (RR 1.2-1.7) among men and women. Lack of coworkers' support increased the frequency of very long sickness absence among men (RR 1.4), and lack of supervisor's support among women (RR 1.6). Also, some interaction effects of social support variables were observed among both genders. We conclude that the studied psychosocial factors are associated with subsequent sickness absence, and that the associations are partly gender-specific. The results showing which variables are related to employees' sickness absenteeism in the private industrial sector can be applied in human resource management and health service planning.  相似文献   
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