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61.
In this study, we investigated the clonal emergence of daptomycin-resistant Enterococcus faecium strains isolated from a patient with leukocyte adhesion deficiency syndrome. The resistance mechanism in these strains is independent of either equivalent point mutations previously described for Staphylococcus aureus or daptomycin inactivation mechanisms identified in soil bacteria.  相似文献   
62.
Purpose  To test the association between night work and work ability, and verify whether the type of contractual employment has any influence over this association. Methods  Permanent workers (N = 642) and workers with precarious jobs (temporary contract or outsourced; N = 552) were interviewed and filled out questionnaires concerning work hours and work ability index. They were classified into: never worked at night, ex-night workers, currently working up to five nights, and currently working at least six nights/2-week span. Results  After adjusting for socio-demography and work variables, current night work was significantly associated with inadequate WAI (vs. day work with no experience in night work) only for precarious workers (OR 2.00, CI 1.01–3.95 and OR 1.85, CI 1.09–3.13 for those working up to five nights and those working at least six nights in 2 weeks, respectively). Conclusions  Unequal opportunities at work and little experience in night work among precarious workers may explain their higher susceptibility to night work.  相似文献   
63.
The aim if this study was to evaluate the effect of sodium overload on blood pressure and renal function in the offspring of diabetic rat mothers. Diabetes was induced with a single dose of streptozotocin before mating. Experimental groups were control (C), offspring from diabetic mother (D), control with sodium chloride (NaCl) overload (CS), and offspring from diabetic mother submitted to NaCl overload (DS). After weaning, all groups received food ad libitum; groups C and D had water ad libitum, and CS and DS received NaCl 0.15 M as drinking water. Renal morphology and function were evaluated in 3-month-old rats. Glomerular area, macrophage infiltration, interlobular artery wall thickness, and renal vascular resistance were significantly increased in CS, D, and DS compared with C. Renal plasma flow (RPF) and glomerular filtration rate (GFR) were decreased in CS and D compared with C. In DS, GFR and fractional filtration were increased, suggesting a state of hyperfiltration. Hypertension was observed in groups D, CS, and DS from 2 months on and was more severe in DS. Our data suggest that diabetes during intrauterine development and salt overload beginning at an early age can cause hypertension and renal injury. When these conditions were associated, morphological and functional changes were much more intense, suggesting acceleration in the process of kidney injury.  相似文献   
64.
Objective: Childhood obesity confers an increased risk of vascular changes and adult cardiovascular disease. Using a high‐resolution ultrasound technique that enables separation of intimal and medial layers, we examined the intimal thickness (IT) and intimal–medial thickness (IMT) of radial (RA) and dorsal pedal (DPA) arteries and the pulse wave velocity (PWV) in overweight/obese children and adolescents and in healthy subjects. Methods and results: IT and IMT of RA and DPA and PWV were measured in 33 obese children and adolescents (13·9 ± 1·6 years) and in 18 matched lean controls (14·3 ± 2·2). Increased RA IT was found in the obese group, whereas no differences in RA IMT or medial thickness were observed. Obese females accounted for the entire difference in RA IT (P = 0·04). DPA IT was inversely correlated with HDL cholesterol in the obese group (?0·56, P = 0·0089). PWV was lower in the obese group than in the lean group (6·2 ± 0·8 versus 7·0 ± 0·9 m s?1, respectively; P = 0·001). Conclusions: Obese children and adolescents, primarily females, present with increased RA IT. The decreased PWV in the obese versus lean subjects might reflect general vasodilatation.  相似文献   
65.
Intramyocellular lipids are of importance in lipid-related diseases. The techniques in this field are limited because of a lack of adequate tools for localization of various lipids. The most usual methods for the localization of lipid distribution in the skeletal muscle are histochemistry and fluorescence probes. Different chromatography methods and mass spectrometry techniques have also been used for lipid identification. Our aim was to localize the spatial distribution of lipids in their native forms by using static time-of-flight secondary-ion mass spectrometry (TOF-SIMS). Human percutaneous skeletal muscle biopsies were obtained from the middle part of the lateral vastus muscle in the right leg of healthy adolescents with a body mass index >30. Samples were prepared by high-pressure freezing, freeze-fracturing and freeze-drying, and analysed by imaging TOF-SIMS equipped with a Bi3+ cluster ion gun. In the positive spectra, we identified phosphocholine, cholesterol, diacylglycerol, phospholipids and triacylglycerol. Phosphocholine was localized to the edge of the fibre, representing the sarcoplasma or endomysium. Weak cholesterol signals were observed in the intracellular areas. High diacylglycerol and low triacylglycerol signal intensities were seen in intracellular spaces of the transversal area of the muscle fibre. In the negative spectra, we identified fatty acids. We observed co-localization of fatty acids and diacylglycerol, which may indicate lipid-storing parts of the skeletal muscle. Thus, TOF-SIMS imaging can be used to depict the heterogeneous localization of lipids in human skeletal muscle.  相似文献   
66.
A new method for treating chlamydial conjunctivitis consists in injections of ciprofloxacine for intravenous injections, which is injected (1 ml) under the inferior vault of the conjunctiva on novocaine pad (0.5 ml 0.5% solution) and intravenously by drip infusion (99 ml) twice daily for 7-10 days. The treatment led to clinical cure in all patients, no relapses were observed. This method ensures a high therapeutic effect and accelerates the recovery of patients with chlamydial conjunctivitis by 4.6 days. The method is recommended for patients with complicated forms of chlamydial conjunctivitis in severe and protracted cases with concomitant urogenital chlamydial infection and concomitant chronic gastrointestinal diseases, when oral antibiotic therapy is undesirable or precluded.  相似文献   
67.
Sinusotomy modification, developed by the authors, consists in combination of traditional subscleral surgery with posterior cyclo-retraction and the formation of an uveal pouch. This technique was used in the treatment of 28 patients (28 eyes) with primary open-angle glaucoma. Immediate hypotensive effect was achieved in all the patients (in one case surgery was paralleled by pilocarpine instillations). Twenty-four patients were examined in late periods (up to 1 year) after surgery. Ophthalmic tone normalization was achieved in 91.7% of cases (in 83.3% of cases no drug instillations were used). Vision acuity and visual field were unchanged or improved in 87.5 and 95.8% of cases, respectively. No grave complications were recorded.  相似文献   
68.
69.
OBJECTIVE: To describe knowledge and practices adopted by high school students to prevent occupational injuries. STUDY DESIGN: The study was carried out in a public school located in S?o Paulo, in 2003. Fifty-three evening students aged 14 to 21 years old participated the study, they were divided into two groups with and without job experience (32 and 21 students, respectively). The students answered two questions: "Why do occupational injuries occur?" and "How do you avoid occupational injuries?" Analyses were performed using the software "Quali-quanti" to structure collective discourses. ANALYSIS OF DISCOURSES: Adolescents with work experience reported that occupational injuries occur due to carelessness of the employee, bad luck of the employee, employer's negligence, lack of training, and unsafe workplace. Adolescents without work experience reported that the main causes of work injuries were carelessness of the employee and employer's negligence. Regarding the ways to protect themselves against occupational injuries, both groups reported that: they pay attention (would pay attention) and wear safety equipment (would wear) safety equipment. CONCLUSIONS: Adolescents from both groups showed limited knowledge about occupational injuries and prevention methods. Students "blamed the victim" to explain the injuries and considered "paying attention to work" as the best way to protect themselves. These facts showed that the culture of blaming the victim is present since adolescence and probably it is an outcome of a learning process of the society.  相似文献   
70.
Characterisation of the AV-node is an important step in determining the optimal form of treatment for supraventricular tachycardias. To integrate and analyse patient-specific measurements, mathematical modelling has emerged as a valuable tool. Here we present a model of the human AV-node, consisting of a series of interacting nodes, each with separate dynamics in refractory time and conduction delay. The model is evaluated in several scenarios, including atrial fibrillation (AF) and clinical pacing, using simulated and measured data. The model is able to replicate signals derived from clinical ECG data as well as from invasive measurements, both under AF and pacing. To quantify the uncertainty in parameter estimation, 1000 parameter sets were sampled, showing that model output similar to data corresponds to limited regions in the model parameter space. The model is the first human AV-node model to capture both spatial and temporal dynamics while being efficient enough to allow interactive use on clinical timescales, as well as parameter estimation and uncertainty quantification. As such, it fills a new niche in the current set of published models and forms a valuable tool for both understanding and clinical research.  相似文献   
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