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排序方式: 共有845条查询结果,搜索用时 15 毫秒
1.
Evaluation of training nurses to perform semi‐automated three‐dimensional left ventricular ejection fraction using a customised workstation‐based training protocol 下载免费PDF全文
2.
A convenience sample of hospital workers, those receiving influenza vaccine and those not receiving vaccine, were asked to complete questionnaires delineating the occurrence of symptoms (e.g., fever, headache, extreme tiredness, dry cough, sore throat, runny nose, stuffy nose, muscle aches) and absenteeism in the 7-day period post-vaccination if vaccinated. Those unvaccinated completed the questionnaire in a self-selected 7 consecutive day period during the study conducted from November 2004 to February 2005. Those receiving either Fluzone or FluMist reported significantly fewer symptoms and related absenteeism than the unvaccinated group (p < .05). Administration of influenza vaccine did not result in higher rates of post-vaccination symptoms as compared to an unvaccinated group. Further, vaccinated employees did not experience higher absenteeism rates as a result of receiving either influenza vaccine. However, for those reporting absenteeism as a result of symptoms, mean absenteeism days were highest in the FluMist group (4.5 days) compared to the unvaccinated group (2.1 days) and the Fluzone group (1.9 days). 相似文献
3.
A S Lamont M S Roberts D G Holdsworth A Atherton J J Shepherd 《Anaesthesia and intensive care》1986,14(4):360-364
Recently, a family tree with a predisposition for the gene of multiple endocrine neoplasia Type 1 has been identified in Tasmania. As the surgical identification and localisation of parathyroid adenomas is facilitated by the administration of methylene blue, an opportunity has presented to measure the plasma concentration of methylene blue and methaemoglobin production. The study was undertaken to establish whether significant methaemoglobin concentrations were generated during the infusion and whether these concentrations could be related to the corresponding methylene blue concentrations. Mean peak methylene blue concentrations of 3.72 micrograms l-1, mean percentage methaemoglobin of 10.0 and a PaO2 within acceptable clinical ranges were found. No apparent relationship between methylene blue concentration and methaemoglobin production was found. 相似文献
4.
Symptomatic zinc deficiency developed in an exclusively breast-fed, full-term infant. Her older brother had also developed zinc deficiency while being exclusively breast-fed. Breast milk zinc concentrations were low throughout lactation, and this inadequacy is the likely cause of the deficiency in both infants. 相似文献
5.
P H Perlstein H D Atherton E F Donovan D K Richardson U R Kotagal 《Health services research》1997,32(3):299-311
OBJECTIVE: To determine to what degree attending physicians contribute to cost variations in the care of ventilator-dependent newborns. DATA SOURCES: Clinical data were merged with hospital financial data describing daily ancillary care costs during the first two weeks of life for 132 extremely low-birthweight newborns. In addition, each patient's chart was reviewed and illness severity graded using both SNAP and CRIB scores. STUDY DESIGN: This was a retrospective cohort of infants with birth weights of less than 1,001 grams and respiratory distress syndrome requiring mechanical ventilation in the first day of life. From birth up to two weeks of life, each received care directed by only one of 11 faculty neonatologists in a single university hospital. Data were analyzed stratified by these physicians. t-Test, ANOVA, and chi-square were used to assess bivariate data. For continuous data, log linear regressions were used. PRINCIPAL FINDINGS: After controlling for illness severity, when stratified by physicians, there were significant variances in the costs of ancillary resources for the study infants (p < .0001). Twenty-nine percent of the variance was attributable to whether or not the hospital day included the use of a ventilator. Physician identity explained only 5.6 percent (p < .0001). CONCLUSIONS: Physician identity was significant but explained less than 6 percent of the total variance in ancillary costs. Whether or not a ventilator was used during care was far more important. We conclude that for very sick babies during the first two weeks of care, reducing variations in ancillary services utilization among neonatologists will yield only modest savings. 相似文献
6.
N D Atherton 《Clinical chemistry》1989,35(6):975-978
Direct-injection analysis for phenylalanine in plasma by isocratic "high-performance" liquid chromatography (HPLC) is described. For chromatographic separation I use an internal-surface reversed-phase silica support. The method involves ultraviolet detection, requires as little as 10 microL of plasma (routinely 20 microL), and supplies results in less than 7.5 min from injection. The intra-batch coefficient of variation for phenylalanine in human plasma samples (197-1104 mumol/L) ranged between 3.0% and 6.0% and the range of linearity was 10-1250 mumol/L for a 20-microL sample injection loop. The upper limit can readily be extended by using a smaller volume loop. Phenylalanine results from direct plasma injection (y) correlated well with those of a protein precipitation/HPLC technique (x): y = 0.931x + 46.4 (r = 0.951, n = 41, range 78-1344 mumol/L). 相似文献
7.
Herpes simplex virus type 1 (HSV-1) expresses a complex of two virally encoded glycoproteins, gE and gl, which is capable of binding nonimmune human IgG. The gE-gl complex has thus become known as an Fc receptor (FcR), which reportedly binds human IgG subclasses in the order IgG4 > IgG1 > or = IgG2 and does not bind IgG3 from many individuals. There is, however, allelic variation in the genes encoding the human IgG1 heavy chain constant region and this gives rise to allotypes of IgG1. Using recombinant monoclonal IgG molecules of known isotype and mutants thereof we have unexpectedly discovered that the HSV-1 FcR discriminates between IgG1 allotypes. This is evidence of functional differences between IgG1 allotypes that may account for their distribution in populations. Furthermore, these findings suggest HSV-1 FcR binding sites on the IgG molecule some distance from the proposed binding site in the CH2-CH3 domain interface. 相似文献
8.
9.
Helen J. Cooke John Atherton Young 《Pflügers Archiv : European journal of physiology》1970,318(4):315-324
Summary Techniques have been developed for collection of urine in embryonic and newly hatched chickens for the purpose of studying the development of renal function.The reliability of EDTA-51Cr as a substitute for inulin-14C in the determination of GFR was studied. Since inulin and EDTA-51Cr clearances in the hatched chicken averaged 1.61±0.23 (S.E.) ml/min per kg body weight and 1.58±0.27 ml/min per kg body weight, respectively, EDTA-51Cr clearance was considered a suitable measure of GFR.GFR increased significantly in the first few days after hatching. Filtration rate was 0.068±0.008 (S.E.) ml/min per g kidney weight in the embryo and increased to 0.148±0.008 ml/min per g shortly after hatching. By nine days after hatching GFR had risen to 0.290±0.015 ml/min per g, a value comparable to that reported for the adult.Clearances of sodium, potassium, chloride and total osmolyte also increased with age. When these clearances were corrected for changing glomerular filtration rates the embryonic chicks were found to excrete a greater percentage of the filtered load. These results show that adult levels of glomerulo-tubular balance are not attained until after hatching.A preliminary report of this work has already been published [3]. 相似文献
10.
Helicobacter pylori genotypes, host factors, and gastric mucosal histopathology in peptic ulcer disease 总被引:10,自引:0,他引:10
Tham KT Peek RM Atherton JC Cover TL Perez-Perez GI Shyr Y Blaser MJ 《Human pathology》2001,32(3):264-273
From 183 patients undergoing upper gastrointestinal endoscopy, we used antral and corpus gastric biopsies for bacterial culture and histopathologic examination, blood samples to detect immunoglobulin G antibodies against Helicobacter pylori, and H pylori genomic DNA to analyze cytotoxin-associated gene A (cagA) and vacuolating cytotoxin (vacA) genotypes. As expected, among H pylori biopsy-positive patients, those with duodenal ulcer (DU) (n = 34) had significantly more severe chronic and acute inflammation (P <.001) and epithelial degeneration (P =.004) in the gastric antrum than in the gastric corpus. Each of those 3 parameters and H pylori density were significantly higher in the antrum of patients with DU than in patients with gastric ulcer (GU) or no ulcer. Colonization with vacA s1/cagA-positive strains of H pylori was associated with inflammation and epithelial degeneration in gastric mucosa and increased risk for peptic ulcer disease (PUD), whereas colonization with vacA s2m2/cagA-negative strains was associated with mild gastric histopathology and was not associated with any significant risk for PUD. The predominant H pylori strains in African Americans were vacA s1bm1/cagA-positive, whereas all genotypes were well represented in non-Hispanic-Caucasians. By multivariate analysis, H pylori colonization was significantly associated with DU (Adjusted odds ratio [AdjOR] = 3.2 [1.4-7.2]) and nonsteroidal anti-inflammatory drugs (NSAID) use was inversely associated (AdjOR = 0.3 [0.2-0.7]). NSAID use (AdjOR = 4.3 [1.02-18.5]) and African-American ethnicity (AdjOR = 10.9 [2.6-50]) were significantly associated with GU. Smoking and age were not significantly associated with either DU or GU. These data indicate that DU is associated with an antral-dominant gastritis, and H pylori genotype and NSAID use independently contribute to the pathogenesis of PUD. HUM PATHOL 32:264-273. This is a US Government work. There are no restrictions on its use. 相似文献