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41.
PURPOSE: To prospectively compare bronchial measurements obtained with three-dimensional quantitative thin-section computed tomography (CT) with those obtained with thin-section CT scores in the assessment of the severity of pulmonary cystic fibrosis (CF). MATERIALS AND METHODS: Ethics committee approval was obtained. Sixteen patients with CF (mean age, 26.6 years; range, 18-42 years) and five healthy volunteers (mean age, 27.4 years; range, 21-44 years) gave written informed consent, underwent multi-detector row CT and a pulmonary function test (PFT), and were divided into three groups: group A, healthy volunteers; group B, patients with mild CF (forced expiratory volume in 1 second [FEV(1)] > 80%); and group C, patients with severe CF (FEV(1) < 80%). Two observers obtained thin-section CT scores with eight scoring systems. Bronchial cross-sectional wall area (WA), lumen area (LA), airway area, and wall thickness (WT) were measured with customized software and were normalized on the basis of subject body surface. Morphologic characteristics, PFT results, thin-section CT scores, and quantitative measurements were compared among the three groups with analysis of variance. Correlations among bronchial measurements, PFT results, and CT scores were calculated with the Spearman correlation coefficient. RESULTS: Thin-section CT scores were different between group C and either group A or group B (P < .05). WA and WT were significantly different among all groups (P < .05). Interscore correlations and correlations between bronchial parameters and scores were high (r > 0.89, P < .0001). Scores, WA, and WT were significantly correlated with PFT obstructive indexes (P < .047). CONCLUSION: WA and WT assessed with dedicated software on multi-detector row CT images allow evaluation of the severity of pulmonary CF.  相似文献   
42.
Purpose In patients with lymphoma, we investigated the impact of contrast-enhanced CT on PET attenuation correction in lesions and normal tissues, particularly when PET/CT was performed after chemotherapy. Methods Fifty patients (51±18 years) with Hodgkin’s disease (n=17) or non-Hodgkin lymphomas (n=33) were studied before and after chemotherapy. PET/CT scans were performed 60 min after injection of FDG. Iopamiron 300 (iopamidol, 1.5 cc/kg) was injected immediately afterwards, followed 50 s later by a second craniocaudal CT (CT+). PET images were successively reconstructed using the unenhanced CT (PET−) and the CT+ (PET+) for attenuation correction, using iterative reconstruction (4 iterations, 8 subsets, 5 mm post-filtering). HUmean, SUVmax and SUVmean were measured before and after chemotherapy in ten non-tumoural ROIs [aorta, femur, kidney, lung, iliopsoas muscle, occipital cortex, T12 vertebra, liver, spleen and inferior vena cava (IVC)] and in tumoural lymphadenopathies or malignant tissues (n=397 and 51 VOIs respectively before and after chemotherapy) using a 3D-thresholding method (identical threshold for PET− and PET+). ROIs were defined on the PET− and automatically applied on the unenhanced CT (CT−), the CT+ and the PET+. Results In the non-tumoural tissues, HUmean increased significantly in the CT+ compared with the CT− in the vessels and the highly vascularised organs, and slight increases were observed in the occipital cortex (+11%), the iliopsoas muscle (+6%) and the femur (+3%). SUVmax increased significantly in the PET+ compared with the PET− in the aorta (+14%), the liver (+10%), the spleen (+10%) and the IVC (+12%). SUVmean increased significantly in the PET+ compared with the PET− in the aorta (+15%), the kidney (+13%), the liver (+11%), the spleen (10%) and the IVC (+12%). In the lesions, HUmean was not significantly different before and after chemotherapy, whatever the normal region considered. SUVmax increased significantly after treatment in the T12 vertebra (+12%). SUVmean increased significantly after treatment in the T12 vertebra (+13%) and in the liver (+12%). HUmean increased significantly in the CT+ compared with the CT− in the lesions (+55%) before chemotherapy. SUVmax and SUVmean increased significantly in the PET+ compared with the PET− in the lesions (+4%) only before chemotherapy. No significant difference was seen in measurements (HUmean, SUVmax and SUVmean) after chemotherapy. Conclusion Our study demonstrates that use of enhanced CT for attenuation correction has a negligible effect on quantification at staging and after chemotherapy. A “single-shot” enhanced PET/CT may thus be performed in the evaluation of patients with lymphoma at staging, during treatment and at follow-up.  相似文献   
43.

Objective

To evaluate frailty, falls and perceptions of ageing among clinically stable individuals with HIV, engaged with remote healthcare delivered via a novel smartphone application.

Methods

This was a multi-centre European cross-sectional, questionnaire-based sub-study of EmERGE participants. Frailty was assessed using the five-item FRAIL scale. Present criteria were summed and categorized as follows: 0, robust; 1–2, pre-frail; 3–5, frail. Falls history and EQ-5D-5L quality of life measure were completed. Participants were asked their felt age and personal satisfaction with ageing.

Results

A total of 1373 participated, with a mean age of 45 (± 9.8) years. Frailty was uncommon at 2%; 12.4% fell in the previous year, 58.8% of these recurrently. Mood symptoms and pain were prevalent, at 43.3% and 31.8%, respectively. Ageing satisfaction was high at 76.4%, with 74.6% feeling younger than their chronological age; the mean felt age was 39.3 years. In multivariable analysis, mood symptoms and pain were positively associated with frailty, falls and ageing dissatisfaction. An increase in pain severity and mood symptoms were respectively associated with 34% and 63% increased odds of pre-frailty/frailty. An increment in pain symptoms was associated with a 71% increase in odds of falling. Pain was associated with ageing poorly, as were mood symptoms, with odds of dissatisfaction increasing by 34% per increment in severity.

Conclusions

Although uncommon, frailty, falls and ageing dissatisfaction were seen in a younger cohort with medically stable HIV infection using a remote care model, promoting screening as advocated by European guidelines. These were more common in those with pain or mood symptoms, which should be proactively managed in clinical care and explored further in future research.  相似文献   
44.
Mutation of the gene for alpha-tocopherol transfer protein causes ataxia with isolated vitamin E deficiency, a disorder usually stabilized or improved after vitamin E supplementation. Dystonia has rarely been described in ataxia with isolated vitamin E deficiency (AVED) patients. We present the case of a young boy with AVED, whose neurological and extra-neurological cardinal symptoms of the disease improved after vitamin E supplementation but who progressively developed generalized dystonia.  相似文献   
45.
Bony fish, and in particular teleosts, represent a morphologically extremely diverse group of vertebrates, well suited to study certain problems in odontogenesis. In this article we address some questions that can benefit much from the use of fish dentitions as paradigms, such as endodermal participation in tooth formation and epithelial primacy in initiation events. Next, we highlight some results recently obtained in our laboratory with respect to two models, the zebrafish (Cyprinidae), and selected species of cichlids (Cichlidae). Finally, we pinpoint some questions that lend themselves admirably to be examined using fish models, such as the factors that control renewed initiation of teeth, and the relationship (or absence thereof) between Hox genes and tooth formation.  相似文献   
46.
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48.
Advanced glycation end-products (AGEs) are found in excess during diabetes mellitus, uremia and aging. Non enzymatique glycation, glycoxidation with glucose auto-oxidation and the polyol pathway are involved in the production of AGEs. Tissue accumulation of AGEs and their binding to cell receptors are critical steps in the deleterious consequences of AGE excess. AGE-receptor interaction altered endothelial cells, macrophages, mesangial and mesothelial cell functions. AGEs appear to be involved in the genesis of diabetic micro but also macro-angiopathy. Reduction of AGE clearance and permanent oxidative stress are responsible for AGE excess during uremia. High-flux hemodialysis and peritoneal dialysis reduce AGE level but kidney transplantation is the best treatment to restore homeostasis. New drugs are tested to reduce AGEs or AGE deleterious effects but the best treatment remains the prevention of AGE formation by a strict glycemic control.  相似文献   
49.
PURPOSE: Advanced glycation end-products (AGEs) accumulate in aging tissues and organs during rheumatoid arthritis and Alzheimer disease. These aging toxins are especially involved in cell alteration during diabetes mellitus (glycotoxin) and renal failure (uremic toxin). AGEs participate to the endothelial dysfunction leading to diabetic macro but also micro-angiopathy. AGEs binding to cell receptors are critical steps in the deleterious consequences of AGE excess. AGE-receptor activation altered cell and organ functions by a pro-inflammatory, pro-coagulant and pro-fibrosis factors cell response. CURRENT KNOWLEDGE AND KEY POINTS: Non-enzymatic glycation and glycoxidation with glucose auto-oxidation represent the two main pathways resulting in AGE formation. No exclusive AGE classification is actually available. Pathophysiological mechanisms are described to explain AGE toxicity. AGEs bind to cell receptors inducing deleterious consequences such as endothelial dysfunction after endothelial RAGE activation. AGEs can also have deleterious effects through glycated protein accumulation or in situ protein glycation. FUTURE PROSPECTS AND PROJECTS: Many in vitro or animal studies demonstrated that AGE deleterious effects can be prevented by glycation inhibitors, AGE cross-link breakers or AGE-RAGE interaction inhibition. New molecules are actually studied as new strategy to prevent or treat the deleterious effects of these aging toxins.  相似文献   
50.
RATIONALE: Small airways constitute a major site of pathology in cystic fibrosis (CF) and provide most of the surface area of the conducting airways of the lung. Little is known, however, about the impact of CF on ion and fluid transport in small (bronchiolar) airways. OBJECTIVES: To describe the ion and fluid transport properties of CF bronchiolar epithelium. METHODS: Primary cultures of human bronchial and bronchiolar (non-CF and CF) epithelial cells were obtained. The bioelectric properties were studied in Ussing chambers and the airway surface liquid (ASL) height was measured with confocal microscopy. MAIN RESULTS: Primary cultures of DeltaF508 CF bronchiolar epithelial cells displayed higher transepithelial resistance than non-CF cultures, whereas baseline short circuit current and amiloride-inhibitable short circuit current were similar in both preparations. The ASL height was significantly smaller in CF compared with non-CF preparations. In the presence of amiloride, addition of forskolin increased short circuit current in non-CF but not in CF bronchiolar cultures, and the ATP-induced increase in short circuit current was lower in CF than in non-CF cultures. Non-CF bronchiolar preparations displayed larger short circuit current and fluid secretion in responses to forskolin than non-CF bronchial preparations, suggesting that CFTR-dependent Cl(-) transport may play a more important role in the regulation of fluid transport in small airways than in large airways. CONCLUSION: In CF small airways, defective Cl(-) secretion combined with unregulated (persistent) Na(+) absorption results in ASLdepletion.  相似文献   
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