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The seasonal distribution of cryptosporidiosis in children in Aragón, a region in northeastern Spain, was determined. Over a period of six years (October 1988 to September 1994), 10,034 stool samples from 4,508 children with gastrointestinal symptoms were analyzed for this purpose. The age of the patients ranged from 1 month to 14 years. Cryptosporidium oocysts were identified in 87 (1.93%) patients. Prevalence was highest (6.20%) in children aged 1 to 3 years old. The prevalence was significantly higher in the autumn-winter period (October to March) than in the spring-summer period (April to September) in the whole population (2.41% vs. 1.35%, p = 0.010) and in the 1- to 3-year-old age group (8.44% vs. 3.20%, p = 0.002), but not in the other age groups. A possible relationship of this pattern to attendance at child care centres is suggested.  相似文献   
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Spore cortex of conditional cortexless mutants of Bacillus sphaericus 9602 was not detectable by electron microscopy unless the medium was supplemented with meso-alpha,epsilon-diaminopimelic acid during sporulation. Other spore structures appeared normal. Spore shape was quite irregular in the absence of meso-alpha,epsilon-diaminopimelic acid.  相似文献   
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During 1981, Miami University and the Ohio Agricultural Research and Development Center (OARDC)cooperatively initiated the operation of eight automated, DC-powered global radiation stations which are well distributed throughout Ohio. Each station is lócated in a relatively open, grassy site at a rurally situated state or federal research facility. Personnel at each facility provide security and assistance in station maintenance. A processor-based data logger at each station scans sensors at one-minute intervals, processes the one-minute observations on an hourly and a 24-hr basis, and stores the processed data. Miami University and OARDC use telephone dial-up telemetry to collect the data at 36 and 24-hr intervals, respectively. Both have developed procedures for checking data quality, data archival, and producing summaries which are made available to individuals and organizations placing requests. Through 31 December 1981, the eight stations had collectively operated a total of 68 months. A total of just 4:5 days of global solar radiation data were lost during that period. A single data logger failure accounted for 1.5 days of that loss; the remainder resulted from modifications of the data loggers to improve data processing and retrieval flexibility. Side-by-side comparisons of the station pyranometers (Eppley PSPs) with “working standards” and inter-station comparisons of clear-day transmissivities indicate that pyranometer performance is very comparable throughout the network.  相似文献   
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Acute pancreatitis was experimentally produced in dogs to study the effect of the disease on glucose tolerance. The k value (glucose disappearance coefficient measured in percentage decrease of glucose/min) calculated from the high-dose intravenous glucose-tolerance test was used to evaluate the glucose tolerance of each dog. Thirty dogs were allotted to 3 groups of 10 dogs each as follows: group I--nonsurgical control dogs; group II--surgical control dogs; and group III--pancreatitis-affected dogs. To increase their susceptibility to diabetes, 50% partial pancreatectomies and ductal catheterizations were performed on group II and III dogs. Saline solution was infused into the ductal systems of group II dogs, and staphylococcal alphatoxin was infused into the ductal systems of group III dogs to produce pancreatitis. The results indicated that (1) high-dose intravenous glucose-tolerance test was an effective tool for determining decreased glucose tolerance in dogs; (2) glucose tolerance of group III dogs was markedly decreased compared with that of group I and II dogs; (3) staphylococcal alpha-toxin produced signs of moderately severe pancreatitis; and (4) 50% partial pancreatectomy and saline solution infusion produced clinical and clinicopathologic signs of mild pancreatitis. To determine if a simplified k value (calculated using 2 or 3 blood samples) could closely approximate the standard k value (calculated using 6 blood samples), simplified k values were derived from the 5- and 60-minute blood sample values. These values closely approximated the standard k values, indicating the simplified value may be used in the clinical situation. The standard k value, however, is preferred for investigative work.  相似文献   
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A new method of estimating intracranial decompensation in man is described. An on-line computer system is connected to an intracranial pressure (ICP) monitoring system to compute regression plots of mean ICP vs standard deviation; standard deviation is used as a measure of ICP instability. Two zones with distinctly different slopes are a characteristic feature of these plots. It is thought that the changes of slope signify intracranial decompensation.  相似文献   
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