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41.
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The safety and risks of percutaneous infraclavicular subclavian vein catheterization, when performed by nonsurgical staff, were studied prospectively in 100 consecutive patients. The overall success rate was 92% (with one attempt, 45%; with two attempts, 85%). The procedure was performed under emergency conditions in 35% of the patients, with a success rate of 88.6%. The success rate was significantly lower in younger patients. Hemodynamic status, respiratory status, and level of expertise of the individual performing catheterization did not affect success rate. Most of the failures (six of eight) were related to presumed thrombosis from prior cannulation of the superior vena cava. Mean duration of catheterization was 7.5 +/- 5.8 days (+/- SD). Minor complications (n = 24) included hematomas, minor bleeding from subclavian artery puncture, and transient premature ventricular ectopic beats. Major complications (n = 6) were pneumothoraces (n = 4) and catheter-related infection (n = 2). The number of attempts made to catheterize the vessel and the level of expertise of the operator had the greatest effect on complication rates. No mortality was associated with this procedure. We have found percutaneous infraclavicular subclavian vein catheterization to be a rapid alternative to surgical cutdown for venous access during cardiopulmonary resuscitation. Pediatric residents can be trained, under direct supervision, to perform this procedure with a high success rate and a low complication rate.  相似文献   
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This study aims to evaluate markers of oxidative stress in Tunisian asthmatic patients and investigate whether their markers are correlated with uncontrolled asthma.This prospective cohort study was conducted on 48 healthy subjects and 60 patients with asthma (34 patients with controlled asthma and 26 patients with uncontrolled asthma). The levels of malondialdehyde (MDA), advanced oxidation protein products (AOPP), and glutathione (GSH), as well as the activities of glutathione peroxidase (GPx) and superoxide dismutase (SOD), were estimated in plasma by spectrophotometry.Asthmatic patients have significantly higher plasmatic levels of MDA and AOPP than healthy controls (p < 0.001). Lower GSH level and GPx activity were found in patients with asthma compared to controls (p < 0.001). In contrast, higher SOD activity was noted in asthmatic patients (p < 0.001).The comparison among the patients with controlled asthma and uncontrolled asthma revealed increased MDA and AOPP levels and SOD activity (p < 0.001) as well as a decreased GSH level and GPx activity (p = 0.004, p = 0.019) in patients with uncontrolled asthma. Spirometry level was significantly correlated with SOD activity (r = 0.447; p = 0.010), whereas no significant correlations were found with the other parameters (MDA, AOPP, GSH, and GPx).Asthmatic patients, especially those with uncontrolled asthma, suffer a high degree of reactive oxygen species (ROS) formation causing considerable oxidative stress. Increased MDA level and SOD activity and reduced GPx activity were predictors of poorly controlled asthma.  相似文献   
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We investigated the efficacy and safety of liposomal clarithromycin formulations with different surface charges against clinical isolates of Pseudomonas aeruginosa from the lungs of cystic fibrosis (CF) patients. The liposomal clarithromycin formulations were prepared by the dehydration-rehydration method, and their sizes were measured using the dynamic-light-scattering technique. Encapsulation efficiency was determined by microbiological assay, and the stabilities of the formulations in biological fluid were evaluated for a period of 48 h. The MICs and minimum bactericidal concentrations (MBCs) of free and liposomal formulations were determined with P. aeruginosa strains isolated from CF patients. Liposomal clarithromycin activity against biofilm-forming P. aeruginosa was compared to that of free antibiotic using the Calgary Biofilm Device (CBD). The effects of subinhibitory concentrations of free and liposomal clarithromycin on bacterial virulence factors and motility on agar were investigated on clinical isolates of P. aeruginosa. The cytotoxicities of the liposome preparations and free drug were evaluated on a pulmonary epithelial cell line (A549). The average diameter of the formulations was >222 nm, with encapsulation efficiencies ranging from 5.7% to 30.4%. The liposomes retained more than 70% of their drug content during the 48-h time period. The highly resistant strains of P. aeruginosa became susceptible to liposome-encapsulated clarithromycin (MIC, 256 mg/liter versus 8 mg/liter; P < 0.001). Liposomal clarithromycin reduced the bacterial growth within the biofilm by 3 to 4 log units (P < 0.001), significantly attenuated virulence factor production, and reduced bacterial twitching, swarming, and swimming motilities. The clarithromycin-entrapped liposomes were less cytotoxic than the free drug (P < 0.001). These data indicate that our novel formulations could be a useful strategy to enhance the efficacy of clarithromycin against resistant P. aeruginosa strains that commonly affect individuals with cystic fibrosis.  相似文献   
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One dose of metyrapone (1.5g) administered at 06.00 h, with subsequent measurement of 11-deoxycortisol and 17-hydroxycorticosteroid (17-OHCS) levels in plasma at 12.00 and 14.00 h, allowed accurate assessment of the pituitary-adrenal reserve. Normal response was defined as achieving a serum 17-OHCS level of more than 10.0 micrograms/100 ml and a 11-deoxycortisol level of more than 6.0 micrograms/100 ml at either 12.00 or 14.00 h. These criteria are based on a group of 18 persons with normal pituitary-adrenal axis, and 86 additional cases responded in this normal range. In this group of 104 subjects, 11-deoxycortisol levels rose to 9.2 +/- 3.5 micrograms/100 ml at noon and 17-OHCS levels to 15.4 +/- 4.7 micrograms/100 ml at 14.00 h. Post-metyrapone 17-OHCS levels were significantly higher than normal cortisol levels at these times (P less than 0.001) and than those observed at 08.00 h on the day of the test, demonstrating stimulation of adrenal corticoid production in addition to blockade of cortisol production by metyrapone. Thirty-one patients found to suffer from secondary adrenal failure showed impaired response. All these patients had limited pituitary-adrenal reserve, either proven by other pituitary-adrenal tests or implicated by severe pituitary disease.  相似文献   
50.

Purpose of Review

Nutraceuticals are a form of complementary and alternative medicine that is commonly used by children and adolescents with migraine. In this review, observational studies, randomized controlled trials, systematic reviews, and meta-analyses on the efficacy and safety of single compound nutraceuticals for the management of migraine in children and adolescents were identified through a literature search of MEDLINE, Embase, and EBM Reviews—Cochrane Central Register of Controlled Trials.

Recent Findings

Twenty-one studies were reviewed, of which 11 were observational studies, 7 were randomized controlled trials, and 3 were systematic reviews. Six different nutraceuticals were included in the review: vitamin D, riboflavin, coenzyme Q10, magnesium, butterbur, and polyunsaturated fatty acids. All but three of the studies assessed the role of nutraceuticals in migraine prevention, while three studies evaluated the role of intravenous magnesium for acute migraine management. Overall, the quality and size of the studies were limited.

Summary

Due to low quality evidence and limited studies, no definite conclusions can be drawn on the efficacy of nutraceuticals for the treatment of pediatric migraine. Future studies are warranted in order to establish evidence upon which to define the role of nutraceuticals in this patient population.
  相似文献   
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