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41.
Tuberculin testing of 176 personnel in a Liverpool hospital showed a total incidence of 68% negative reactors. This remarkably high percentage was similar for each of the various groups of workers tested. We did not find the Tine test to be a satisfactory method of screening for tuberculin sensitivity because 30% were doubtful reactors. In these, further tuberculin testing by the Mantoux reagent was always positive. 相似文献
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Hamilton SJ Holley KM Buhl KJ Bullard FA Ken Weston L McDonald SF 《Ecotoxicology and environmental safety》2005,61(1):7-31
Adult razorback sucker (Xyrauchen texanus) were exposed to various selenium concentrations in ponds and isolated river channels of the Colorado River near Grand Junction, CO, to determine effects on their growth and residue accumulation over an 11-month period. Adults at Horsethief ponds were fed a commercial diet, whereas fish at Adobe Creek channel and North Pond foraged on natural food items. Selenium concentrations at Horsethief were 2.2 microg/L in water, 0.1-1.4 microg/g in sediment, and 2.3-3.1 microg/g in food organisms (1.1 microg/g in commercial fish food), at Adobe Creek were 3.8 microg/L in water, 0.5-2.1 microg/g in sediment, and 4-56 microg/g in food organisms, and at North Pond were 9.5 microg/L in water, 7-55 microg/g in sediment, and 20-81 microg/g in food organisms. The selenium concentrations in muscle plugs from adults at Adobe Creek (11.7 microg/g, SD = 0.4, n = 6) and North Pond (16.6 microg/g, SD = 1.0, n = 6) were greater than at Horsethief (4.5 microg/g, SD = 0.2, n = 6). During a depuration period adults from Adobe Creek and North Pond lost 1-2% of their selenium burden in 32 days and 14-19% in 66 days. Selenium accumulated in razorback sucker above toxic thresholds reported in other studies, yet those residues were less than those reported in muscle plugs of 40% of wild razorback sucker caught in the Green River, Utah. 相似文献
45.
Ouwenga MK Sharma SK Holley P Turk TM Perry KT 《Journal of endourology / Endourological Society》2005,19(7):894-897
PURPOSE: We compared the load-release points of the Stone Cone and the new Cook Urological NTrap devices using an in vitro model of the ureter. MATERIALS AND METHODS: A strictured-ureter model was created using urethane tubing with a wire tie around it. A plastic bead was lodged above this narrowing. The Stone Cone, then the NTrap, was deployed in turn above this bead. The force required for each device to undeploy was measured over five trials. RESULTS: Each device released the bead in every trial. The Stone Cone released at a mean of 0.190 lb, while the NTrap yielded at 0.861 lb. CONCLUSIONS: Both of the devices released the plastic bead reliably and at low loads, although the NTrap did require statistically significantly more force than the Stone Cone. However, the loads for both devices were <1 lb, so the devices are unlikely to result in ureteral trauma. Whether a slight increase in load-release force or differences in design result in better stone-clearing ability of one device should be assessed in clinical trials. 相似文献
46.
Sambuughin N Holley H Muldoon S Brandom BW de Bantel AM Tobin JR Nelson TE Goldfarb LG 《Anesthesiology》2005,102(3):515-521
BACKGROUND: Malignant hyperthermia (MH) is a life-threatening and frequently fatal disorder triggered by commonly used anesthetics. MH susceptibility is a genetically determined predisposition to the development of MH. Mutations in the ryanodine receptor type 1 (RYR1) gene are the major cause of MH susceptibility. The authors sought to develop a reliable genetic screening strategy based on efficient and relatively inexpensive mutation-detection procedures. METHODS: A cohort (n = 30) of North American MH patients and MH-susceptible individuals was studied. RNA and DNA extracted from muscle tissue or blood lymphocytes were used for analysis. The entire RYR1 coding region was amplified in 57 overlapping fragments and subjected to denaturing high-performance liquid chromatography analysis followed by direct nucleotide sequencing to characterize RYR1 alterations. RESULTS: Nine previously reported and nine unknown RYR1 mutations were identified in 21 of 30 studied patients (70%). Some of the new mutations were located outside of known mutational "hot spots," suggesting that RYR1 contains previously unknown mutation-prone areas requiring analysis. The North American MH/MH-susceptible population is characterized by a high RYR1 allelic heterogeneity. CONCLUSIONS: Denaturing high-performance liquid chromatography analysis of RNA samples extracted from the biopsied skeletal muscle followed by DNA sequencing is a highly efficient methodology for RYR1 mutation detection. This approach allows increasing the rate of mutation detection to 70% and identifying mutations in the entire RYR1 coding region. 相似文献
47.
This report describes a case in which the diagnosis of sickle cell disease (SCD) was established after death. The diagnosis of sickle cell syndrome was made in a 68 year old black patient who was found to have sickled red blood cells in many organs at necropsy although the disease had not been diagnosed during her lifetime. DNA was isolated from a peripheral blood smear obtained on the day of the patient's death. The beta globin gene was polymerase chain reaction amplified and sequenced, revealing that the patient had S-beta(+) thalassaemia. This study shows that blood smears are a suitable source for retrospective DNA analysis studies. This case illustrates that relatively "mild" forms of SCD can be overlooked, despite symptomatology suggestive of a sickle syndrome, and demonstrates the feasibility of the postmortem molecular diagnosis of haemoglobinopathies in such cases. 相似文献
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49.
Levy JI Welker-Hood LK Clougherty JE Dodson RE Steinbach S Hynes HP 《Environmental health : a global access science source》2004,3(1):13
Background
Children in urban public housing are at high risk for asthma, given elevated environmental and social exposures and suboptimal medical care. For a multifactorial disease like asthma, design of intervention studies can be influenced by the relative prevalence of key risk factors. To better understand risk factors for asthma morbidity in the context of an environmental intervention study, we conducted a detailed baseline evaluation of 78 children (aged 4–17 years) from three public housing developments in Boston. 相似文献50.
Intensive management of patients with type 1 diabetes improves control and reduces rates of long-term complications. Telephone care as an adjunct to office visits is important in the management of children with type 1 diabetes in pediatric endocrine practices in the USA. The goal of this project was to assess the personnel costs and patients' perceptions of telephone care in a moderately sized pediatric diabetes care center (301 patients with a diagnosis of type 1 diabetes). There were two parts to this study. First, telephone logs were kept by three pediatric endocrine nurses (2.2 full-time equivalents [FTEs]) and three pediatric endocrinologists (2.0 FTEs) for two 1-wk blocks. Computerized databases were used to determine the number of clinic visits in 1998. Second, a survey assessing the frequency, perceived value and consequences of phone contact with the diabetes team was distributed to 40 families at clinic visits. Mean nurse/certified diabetes educator (CDE) time spent on the phone was 12.1 h/wk, with an additional 9.7 h/wk spent preparing and documenting. Physicians spent 6.4 h/wk on the phone, and 6.1 h/wk preparing/supervising/documenting. For our 301 patients with diabetes, the weekly personnel cost for telephone care at our institution was 1367 US dollars or 236 US dollars/patient/yr. Of the families surveyed, 80% reported that they had used the phone to obtain care for their child with diabetes and 55% had paged the doctor on call in the previous 6 months. Seven patients reported that phone contact prevented a total of 13 emergency department (ED) visits and 35 office visits. Using a cost estimate of 550 US dollars per ED visit, and 103 US dollars per office visit, the cost of prevented visits was 232 US dollars/patient/yr in our center. These data indicate that telephone care is effective in reducing the cost of reimbursable care via the ED and office visits, as well as avoiding hospitalization. However, the cost of providing this telephone care is not reimbursable to providers. 相似文献