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101.
102.
The complement system is of major importance in the defence against infections. Deficiencies in one of the three pathways of activation of the complement system can cause serious infections; the classical pathway, the alternative pathway and the lectin pathway. A new ELISA assay has been developed to enable the assessment of the functional activity of the whole lectin pathway and to determine the classical and the alternative pathway functional activity in a simple uniform design.  相似文献   
103.
Physical activity in daily life in patients with chronic low back pain   总被引:5,自引:0,他引:5  
OBJECTIVES: To evaluate disuse (ie, a decreased daily physical activity level) in patients with chronic low back pain (LBP) and to evaluate the construct validity of accelerometry for measuring physical activity in daily life. DESIGN: Case-control study in a cross-sectional design; comparison of accelerometry to the criterion standard (doubly labeled water technique). SETTING: Normal daily living (unrestricted by the measurement devices). PATIENTS: Thirteen patients with chronic nonspecific LBP and 13 age- and gender-matched healthy controls. MAIN OUTCOME MEASURES: Physical activity in daily life, expressed as whole-body acceleration measured with a triaxial accelerometer (Tracmor), and as the ratio between average daily metabolic rate (ADMR), measured by the doubly labeled water technique, and resting metabolic rate (RMR), measured by the ventilated hood. Both techniques were used simultaneously for 14 days. RESULTS: Mean physical activity level in patients and controls did not differ significantly. The correlation between the Tracmor and ADMR and RMR was .72 (p < .01). CONCLUSIONS: Decreased physical activity levels in this sample of chronic LBP patients was not confirmed. The Tracmor is a valid instrument for measuring daily activity in LBP patients.  相似文献   
104.
OBJECTIVE: To study whether chair configuration influences sitting balance in persons with spinal cord injury (SCI). DESIGN: Cross-sectional group study. SETTING: Rehabilitation centers and hospital rehabilitation departments. PATIENTS: Ten complete high thoracic SCI (level T2-T8) patients, 10 complete low thoracic SCI (T9-T12) patients, and 10 matched able-bodied controls. SCI participants had completed their active rehabilitation at least 6 months before the study. INTERVENTIONS: A balance-changing (forward) reaching task while seated in four differently configured chairs. Tilt angle (7 degrees and 12 degrees) and reclination angle (22 degrees) were varied relative to a standard chair configuration (10 degrees reclination). MAIN OUTCOME MEASURES: Maximal unsupported reaching distance, center-of-pressure displacement and muscle activity. RESULTS: Although no significant difference in actively controllable reach was found in controls or in subjects with low SCI, sitting balance improved in all chairs relative to the standard chair. Ability to control displacement of arms and trunk during reaching improved. No apparent need for additional postural muscle activity was found. Persons with high SCI did not improve their sitting balance. They were unable to control a shift in body mass larger than the one induced by arm movement. However, they had less muscle activity after backrest reclination or tilting the chair backwards. CONCLUSIONS: The tested chairs had an overall positive effect. However, for individually tailored chair configurations factors other than those investigated should be considered.  相似文献   
105.
The complement system is involved in several aspects of renal disease, including primary renal diseases, dialysis and renal transplant rejection. Initially, a role for complement in renal disease was inferred solely from the deposition of complement components in affected kidneys and changes in complement levels in the circulation during active disease. Recent studies have shown how complement modulates the onset, development and the resolution of renal disease. Current research provides clues on the role of individual complement components and activation pathways as well as possible modes of complement regulation in the management of renal disease.  相似文献   
106.
107.
Eosinophilic enteritis is a rare disease which may mimic acute abdominal emergency. Two sonographically documented cases are presented, which were subsequently proven at operation. Although the sonographic features of severe echolucent bowel wall thickening were not specific, combination with clinical and laboratory data may suggest the correct diagnosis.  相似文献   
108.
The relationship between blood pressure and subjective complaints concerning physical well-being has been investigated. The complaints have been measured by means of the Inventory of Subjective Health. The total number of complaints are the summation of 39 items.Hypertension is assumed to have no clear-cut symptoms. This statement gives rise to the hypothesis that there is no relationship between blood pressure and subjective complaints. The hypothesis was refuted after several tests. We found a curvilinear relationship between diastolic blood pressure and subjective complaints in representative groups of men of 21–65 and 31–50 years old, valid for the total number of complaints and dizziness. This curvilinear relationship is found again after a matching procedure in order to exclude possible confounding effects of age, cigarette smoking and knowledge about elevated blood pressure status.The total number of complaints of males with a diastolic pressure higher than 95 mmHg are not significantly higher than the total number of complaints of males with a lower diastolic pressure, but the difference is significant for dizziness.  相似文献   
109.
Anti-C1q autoantibodies are present in the serum of patients with different autoimmune diseases such as systemic lupus erythematosus (SLE). The occurrence of these autoantibodies correlates with renal involvement. In the present study we examined whether injection of rabbit antimouse C1q antibodies in mice leads to deposition in kidneys. Injection of healthy mice with a single dose of rabbit IgG antimouse C1q antibodies resulted in deposition of both C1q and IgG anti-C1q in glomeruli. The pattern of deposition observed in the glomeruli of mice injected with antimouse C1q antibodies both at 24 h and 2 weeks was both glomerular basement membrane (GBM)-associated and mesangial. Injection of control IgG did not have a detectable effect on circulating C1q levels, and no deposition of either C1q or rabbit IgG was seen at 24 h. The deposition of rabbit antimouse C1q and C1q in glomeruli resulted in complement activation, as assessed by C3 deposition, and influx of leucocytes associated with albuminuria in some, but not all mice. In none of the control mice was albuminuria observed. This report is the first to show that anti-C1q antibodies deposit in the healthy glomerulus together with autologous C1q. This deposition is stable for at least 2 weeks, causes complement activation, leucocyte influx and can lead to mild albuminuria.  相似文献   
110.
The contribution of the lateral suprasylvian cortex to pattern recognition was studied by behavioural detection experiments in combination with bilateral lesions of different parts of the lateral suprasylvian areas (LSA) and area 7 in seven cats. In a two-alternatives forced choice task the cats had to discriminate simple outline patterns which were additively superimposed on a structured visual background made up of broadband Gaussian noise. For various stimulus conditions (moving or stationary patterns and/or background) the detection probability (P D) of the cats was measured as a function of the signal to noise ratio (S/N). Each cat was tested before and after the lesion. Four different types of lesion could be distinguished depending on their extent: (1) lesion of parts of the (LSA); (2) lesion of parts of the LSA with undercutting of areas 17, 18 and 19; (3) lesion of area 7; (4) lesion of area 7 and parts of the LSA.
1.  We found that a large bilateral lesion of the LSA led to significant deficits in all test situations which were dependent on the existence of relative velocity of moving patterns against a structured background. The ability of the cats to discriminate simple outline patterns which were kept stationary was not reduced. On the contrary, when they were tested with stationary and moving patterns on unfocused (empty) backgrounds, we found, to our great surprise, that the performance of the lesioned cats was significantly improved compared with intact animals. As these lesioned cats had no deficits with moving patterns on a uniformly grey background, we conclude that the deficits with the moving patterns must have been caused by interactions between patterns and background, and not by movement of a pattern per se.
2.  As soon as the lesion of the LSA was extended by a bilateral undercutting of areas 17, 18 and 19 we found very severe deficits in all test situations, regardless of whether the patterns were moving or kept stationary, or whether they were superimposed on a background or not. The most substantial deficits occurred when the patterns were moving on a stationary background. In these situations the cats were no longer able to reach the 84% correct criterion. Again, the cats were able to reach criterion with moving patterns on a uniformly grey background indicating that this deficit is probably caused by the interaction of patterns and background and not by motion of the patterns per se.
3.  A large lesion of area 7 led to modest but significant deficits of more or less the same degree in all test situations with the exception of quickly moving patterns on a structured background. In contrast, a much smaller lesion of area 7 yielded significant deficits only when the background was moved and there was a low relative velocity between the patterns and the background.
4.  In brief, the combination of a lesion of area 7 with that of the LSA roughly provoked a combination of the effects of the two lesions (1 and 3) alone. We found significant deficits in all test situations.
We did not find evidence for any type of functional recovery in any of the lesions described. All deficits were permanent. Our results support the idea of a functional segregation between the LSA and area 7. They confirm that the LSA are involved in pattern recognition whenever it is associated with motion in combination with object-background interactions. This suggests an involvement of the LSA in the analysis of object- and self-induced motion. An interpretation of the results of lesioning area 7 is based on the conjecture that the mechanism of vergence movements or of binocular fusion of both retina images might be impaired. Under this condition it seems conceivable to expect double images or a reduced visual acuity because the images are out of focus. This would have a similar effect on the detection performance in each stimulus configuration. In addition, the results of lesion 4 provide evidence that both functional subunits (LSA and area 7) are not able to compensate for one another. Finally, we conclude from the results after lesion 2 that the LSA is part of a system which is based on the cooperation with striate cortex and requires intact primary cortex for its full function.  相似文献   
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