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51.

Aim

To document, describe and raise awareness of a preventable injury associated with the use of disposable barbecues.

Methods

We conducted a retrospective study of incidents involving barbecue burns. Cases were identified through the burn injury database of a tertiary paediatric burns referral centre and case notes reviewed. Experiments were performed to evaluate the dissipation of heat from sand.

Results

Over a 3-month period, 9 children were identified out of a series of 296. The median age was 5 years and burns were sustained through contact with hot sand where disposable barbecues had been used. 87% (n = 13) of the burns were partial thickness and most affected critical areas such as the hands and feet. The majority (93%) responded well to debridement and simple dressings and all patients made a complete recovery. Experiments show that, even after a prolonged period of time, sand can retain sufficient heat to cause a contact burn.

Discussion and conclusion

We have noted an increased incidence of burns with this mechanism of injury. The burns are usually superficial, they tend to occur predominantly in children and involve critical areas. We suggest that areas where disposable barbecues have stood should be cooled and children kept away from the area for at least 5 min. The results of the study have been forwarded to the Prevention Committee of the British Burn Association with the aim of raising awareness of this mechanism of burn.  相似文献   
52.
Enzymes involved in vitamin B6 metabolism, i.e., pyridoxal kinase, pyridoxamine (pyridoxine) 5'-phosphate oxidase, and pyridoxal 5'-phosphate phosphatase, were assayed in hemolysates prepared from cord, maternal, and control blood samples. Mean cord and control pyridoxamine (pyridoxine) 5'-phosphate oxidase activities were significantly higher than maternal activities (p less than 0.001 and p less than 0.05, respectively). A significant correlation (p less than 0.001) was observed between maternal and cord vitamin B6-metabolizing enzymes. Cord pyridoxal 5'-phosphate levels correlated significantly with maternal pyridoxal 5'-phosphate levels (p less than 0.001) and with cord pyridoxal kinase activity (p less than 0.05). Maternal pyridoxal 5'-phosphate levels appear to be the most important factor determining fetal vitamin B6 status.  相似文献   
53.
BACKGROUND: Because of the lack of a problem-free, reliable method for determination of erythrocyte acetylcholinesterase (AChE), we developed a simple kinetic method, which we found to be both reliable and suitable for automation in the routine clinical laboratory. METHODS: Acetylthiocholine, used as substrate, is hydrolysed by acetylcholinesterase to yield acetate and thiocholine. Thiocholine reacts with dichlorophenolindophenol, a blue coloured compound, which is reduced to a colourless product, producing a linear decrease in absorption at 606 nm. If required, this assay can also be run at 600 nm with equally acceptable results. RESULTS: The method was automated on the Synchron LX20 multianalyser (Beckman Instruments) and blood samples of 80 patients with clinically symptomatic organophosphate poisoning and 153 normal controls were evaluated. Acetylcholinesterase values were in the range of 0-14 UgHb(-1) in cases of organophosphate poisoning, in contrast with normal controls, who had AChE values of 24.4--37.9 UgHb(-1). No overlap was found between AChE values of controls and poisoned cases. Intra- and inter-assay coefficients of variation were 1.68 and 3.71%, respectively. CONCLUSION: The method we propose for measurement of AChE was found to be simple, reliable and easily automatable in the routine clinical laboratory.  相似文献   
54.
Management of HIV-infected and exposed children is challenging for health workers in primary care settings. Integrated management of childhood illness (IMCI) is a WHO/UNICEF strategy for improving morbidity and mortality in under 5 children attending first level facilities in developing countries. In high HIV-prevalence settings, IMCI includes an HIV component for identification and management of HIV-infected and exposed children, which requires health workers to ask all mothers about their HIV status and check all children for signs of HIV. Effective implementation of the HIV component depends on the ability and willingness of health workers to take every opportunity to identify HIV-infected children during routine care, and implementation in South Africa is poor.  相似文献   
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Plasma pyridoxal-5'-phosphate (PLP) concentration has been suggested as a valid indicator to assess vitamin B-6 nutritional status. Animal and human studies have shown that plasma PLP concentrations decrease progressively during pregnancy and large doses of vitamin B-6 supplementation are required to maintain plasma PLP at early or prepregnant levels. PLP is known to be hydrolyzed to pyridoxal (PL) by alkaline phosphatase (ALP), resulting in an inverse relationship between PLP and ALP. The object of this study was to compare the PLP-PL equilibrium in a group of healthy pregnant females with that of an age-matched nonpregnant control group from a similar socioeconomic background. The mean plasma PLP level was 37% lower, (P less than 0.0001), whereas the mean PL level was almost 90% higher (P less than 0.001) in the pregnant group than in the nonpregnant control group. The total amount of plasma PLP and PL levels, however, did not differ significantly (P greater than 0.24) between the two groups. Because the PL vitamer is regarded as the ultimate transport form of vitamin B-6, it may serve as a readily available source of vitamin B-6 to meet possible increased metabolic demands. Therefore, the estimation of plasma PLP alone does not permit an accurate assessment or understanding of the nutritional status and the physiology of vitamin B-6 in conditions associated with altered vitamin B-6 homeostases.  相似文献   
57.
Summary Vitamin B6 nutritional status is assessed by measuring the plasma concentration of one of its vitamers, pyridoxal-phosphate (PLP). Several conditions, e.g., myocardial infarction (MI), can disturb the dynamic equilibrium between the different vitamers resulting in transiently low plasma PLP levels. An important question is whether these low plasma PLP levels observed during MI represent a transient state of deficiency and what the possible clinical consequences of such a fall in plasma PLP could be. Since the main metabolic function of PLP is to act as an intracellular coenzyme, it was decided to monitor the changes not only of PLP but also of PL (transport form of vitamin B6) in both the plasma and red blood cells (RBCs) in patients with myocardial infarctions (MI): 16 patients with proven MI were investigated measuring the aforementioned parameters at regular intervals. It was found that the approximately 40% fall in plasma PLP levels was accompanied by an equivalent increase in RBC PLP levels. Subsequently plasma PLP concentrations returned to normal but RBC PLP values were maintained at the newly elevated steady state (without any vitamin supplementation). Since membranes are impermeable to PLP, the only way in which PLP could have been redistributed to the intracellular compartment was through hydrolysis to PL and rephosphorylation once inside the RBCs. This compartmentalization could be an important adaptive response since it has been shown that PLP reduces O2 affinity of deoxygenated hemoglobin, thereby facilitating O2 delivery to the tissues. In addition it would also enhance the proposed storage function of RBCs for PLP and PL which is said to be an important source for muscle vitamin B6 which again is essential for energy production by the muscle cells during ischemia.Abbreviations AST Aspartate Aminotransferase (EC 2.6.1.1) - CK Creatine Kinase (EC 2.7.3.2) - CV coefficient of variation - HPLC high performance liquid chromatography - LD lactate dehydrogenase (EC 1.1.1.27) - MI myocardial infarction - MRC Medical Research Council - NAD+ oxidized nicotinamide adenine dinucleotide - NADH reduced nicotinamide adenine dinucleotide - PL pyridoxal - PLP pyridoxal-5-phosphate - PLSC pyridoxal semicarbazone - PLPSC pyridoxal-5-phosphate semicarbazone - PM pyridoxamine - PMP(PNP)-oxidase pyridoxamine-phosphate- (pyridoxine-phosphate) — oxidase - PN pyridoxine - RBCs red blood cells - SEM standard error of the mean  相似文献   
58.
OBJECTIVE: To examine the effects of the inclusion of extruded dry beans in the diet on serum lipoprotein, plasma fibrinogen, plasma viscosity and plasminogen activator inhibitor 1 (PAI-1) levels. SUBJECTS AND STUDY DESIGN: Twenty-two free living hyperlipidaemic men participated in this randomised, controlled, cross-over study. The subjects were randomly assigned to one of two groups. After a run-in period of four weeks, during which subjects followed their normal diet with the exclusion of dry beans, group A had to include 110 g/day of extruded dry beans in the form of baked products for four weeks while group B continued with the run-in diet. A washout period of four weeks followed after which the experimental intervention was crossed-over. Anthropometric measurements, serum lipoproteins and haemostatic variables were measured with standard methods and dietary intakes were estimated with five-day dietary records at the beginning and end of each experimental period. RESULTS: Compliance was determined as 83.5% with a mean intake of 91. 9 g/day extruded dry beans. Extruded dry beans did not have significant effects on total serum cholesterol, low density lipoprotein cholesterol, triglycerides, apolipoprotein A or B, plasma fibrinogen and plasma viscosity concentrations. High density lipoprotein cholesterol concentrations decreased in both the dry bean and control periods. Lipoprotein (a) concentrations increased with intake of extruded dry beans, but this increase was probably not due to an independent effect of extruded dry beans. Plasminogen activator inhibitor 1 levels were significantly lower after the intake of extruded dry beans compared to the control period. CONCLUSIONS: The inclusion of 91.9 g extruded dry beans per day in the diet had no effects on serum lipoproteins, plasma fibrinogen and viscosity levels but decreased PAI-1 levels. Sponsorship: Dry Bean Producers Organisation (South Africa) and the Potchefstroom University for Christian Higher Education, Potchefstroom, South Africa.  相似文献   
59.
60.
In 34 patients with acute myocardial infarction (MI) plasma pyridoxal-5'-phosphate (PLP) levels were significantly lower (5.22 +/- 1.88 ng/ml) than those in an age- and sex-matched control group (11.5 +/- 2.03 ng/ml). In another group of patients who had clinical and angiographic evidence of ischaemic heart disease but had not had an MI plasma PLP levels were not significantly different from those in the control group (10.07 +/- 2.98 ng/ml). However, plasma high-density lipoprotein cholesterol levels in this group (0.75 +/- 0.28 mmol/l) as well as in the MI group (0.76 +/- 0.28 mmol/l) were significantly lower than those in the control group (1.26 +/- 0.23 mmol/l). On follow-up, all of 15 patients who had had an acute MI showed a continuous decrease in plasma PLP levels of approximately 50% during the first 48 hours after admission. Sixteen healthy volunteers subjected to a period of prolonged fasting (+/- 30 hours) displayed a decrease of approximately 43% over this period. We conclude that an acute reduction in plasma PLP levels occurred during the acute phase of MI. Other factors, for example prolonged acute starvation, may also produce a rapid decrease in plasma PLP levels.  相似文献   
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