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81.
Objectives - To determine whether dexamethasone `matures' the phosphatidylcholine (PC) composition of broncheoalveolar fluid in infants at high risk of neonatal chronic lung disease (CLD), either by increasing the proportion of dipalmitoylphosphatidylcholine (DPPC), expressed as a percentage of total PC (%DPPC), or by increasing the ratio of DPPC to palmitoyloleoylphosphatidylcholine (DPPC:POPC ratio).  相似文献   
82.
Short-term and long-term carcinogenicity of methyl carbamate (MCB) was evaluated in F344 rats and B6C3F1 mice. In experiments lasting 6, 12, and 18 months, MCB was given in water by gavage to groups of 10 male and 10 female rats at 0 or 400 mg/kg body weight, 5 days per week, and to similar groups of mice at 0 or 1,000 mg/kg. At 6 months, MCB induced atypical mitoses, cytologic alterations, cytomegaly, pigmentation, necrosis, and neoplastic nodules of the liver in rats. At 12 and 18 months, carcinomas of the liver were induced by MCB in 80-90% of male rats and in 60-80% of female rats. None was observed in control rats or in mice. In the 2-year studies, MCB was given to groups of 50 male and 50 female rats at 0, 100, or 200 mg/kg and to similar groups of mice at 0, 500, or 1,000 mg/kg, 5 days/week. Chronic focal inflammation, cytologic alteration, hyperplasia, and neoplastic nodules and carcinomas (200 mg/kg groups only) of the liver were induced by MCB in rats. Liver tumor incidence data for combined experiments in rats were: males--5% in controls, 0% in 100 mg/kg group, 14% in 200 mg/kg group, and 77% in 400 mg/kg group; females--5% in controls, 0% in controls, 0% in 100 mg/kg group, 12% in 200 mg/kg group, and 63% in 400 mg/kg group. MCB was not shown to be carcinogenic in mice.  相似文献   
83.
Salmonella arizonae are rarely isolated in the UK. Since 1966 there have been sixty-six isolates from humans of whom 35% gave a recent history of foreign travel. Terrapins and snakes are potential sources of infection.  相似文献   
84.
Cytokines (IL-1 alpha and IL-2) and soluble interleukin 2 receptors (sIL-2r) were evaluated in patients with rheumatoid arthritis (RA) and controls. In RA, serum sIL-2r and IL-1 alpha were increased, and sIL-2r were significantly higher in synovial fluid than in serum. Serum levels of sIL-1r but not IL-1 alpha were increased in patients with acute infections, suggesting additional discriminatory specificity for IL-1 alpha. Both tender and swollen joint scores were higher for patients with RA with serum sIL-2r levels greater than or equal to 700 U/ml. Quantitation of immune mediators may be useful in the clinical assessment of RA in addition to their implication regarding the pathogenesis of the disease.  相似文献   
85.
Students in grades 1 through 6 were assessed on 11 ocular functions. A multivariate correlation was made between these ocular functions and the students' reading ability, as measured on the Stanford Achievement Test. There were no significant multivariate correlations between the ocular functions and the students' reading ability. It was concluded that for students with small heterophorias and no significant refractive errors, a relationship did not exist between ocular functions and reading ability.  相似文献   
86.
We describe a case of giant cavernous haemangioma of the liver with disseminated intravascular coagulopathy (Kasabach-Merritt syndrome) which was cured by orthotopic liver transplant.A 47 year old man presented with bleeding and tender massive hepatomegaly after tooth extraction. Investigations showed disseminated intravascular coagulopathy and a giant hepatic haemangioma involving both lobes of the liver. Initial treatment failed to resolve the coagulopathy and liver resection was attempted. At laparotomy the turnout was unresectable and the only option for cure was to offer a liver transplantation. The orthotopic liver transplant was performed 20 days after initial laparotomy. Subsequently, all coagulation parameters returned to normal and the patient remains well after 12 months. Orthotopic liver transplant can be considered for giant hepatic haemangioma with Kasabach-Merritt syndrome when resection is necessary and a partial hepatectomy is not technically feasible.  相似文献   
87.
The aim of the study was to distinguish infection from inflammation in patients with suspected infection using technetium-99m Infecton. Ninety-nine patients (102 studies) referred for infection evaluation underwent imaging with 400 MBq99mTc-Infecton at 1 and 4 h. Most patients had appropriate microbiological tests and about half (56) had radiolabelled white cell scans as well. No adverse effects were noted in any patient. The clinical efficacy of99mTc-Infecton depended in part on whether imaging was undertaken during intibiotic therapy for infection or not. In consultation with the microbiologist, 5–14 days of appropriate and successful antibiotic therapy was considered adequate to classify some results as true-negatives. The figures for sensitivity and specificity of99mTc-Infecton for active or unsuccessfully treated infection were 83% and 91% respectively. It is concluded that99mTc-Infecton imaging contributed to the differential diagnosis of inflammation. It is being used as the first imaging modality when bacterial infection is suspected.  相似文献   
88.
The purpose of the present studies was to determine whether reproductive development in male musk shrews (original stock from Guam Island, 13 degrees N latitude) could be altered by small, ecologically relevant changes in photoperiod. In the first experiment, effects of changes in photoperiod equivalent to those seen between the 2 solstices on Guam Island (90 min) on reproductive maturation were investigated. The results showed that a 90-min difference in photoperiod had a significant effect on weights of various androgen-sensitive target tissues. Furthermore, there was little evidence that the preweaning photoperiod had an effect on the response to the postweaning photoperiod. In the second experiment, effects of changes in photoperiod equivalent to those seen between the equinoxes and solstices on Guam Island (45 min) on reproductive maturation were investigated. The results showed that both a decrease and an increase in photoperiod by 45 min had a significant effect on weights of various androgen-sensitive target tissues. Overall, these results suggest that animals living close to the equator can potentially use small changes in day length to alter or time reproductive function.  相似文献   
89.
The aetiopathogenesis of haemorrhagic shock encephalopathy syndrome (HSES) remains unclear and after concern that a novel environmental agent was the cause, the British Paediatric Association and the Public Health Laboratory Service Communicable Disease Surveillance Centre in 1983 initiated surveillance of this condition in the British Isles. After 1986 cases were ascertained via the British Paediatric Surveillance Unit 'active' reporting scheme; this report presents the findings for 1985-8. Sixty five patients were reported, of whom 52 satisfied the criteria for inclusion. Of those whose outcome was known, 24 (46%) died, 18 had severe neurological damage, and six survived apparently intact. Epidemiological features of note were: the median age of 15 weeks (range 3-140); statistically significant clustering of admission times suggesting a peak onset period at night; lack of geographic clusters, of secular trends and, except for a slight excess in winter months, of seasonality. Clinical and pathological features followed a highly consistent pattern, suggesting that HSES is an individual clinical entity distinguishable from conditions with similar presentations, such as septicaemia and Reye's syndrome. There was no microbiological or epidemiological evidence to support the emergence of a novel environmental agent. Many of the features of HSES were, however, the same as those described in heat stroke and we suggest that the two conditions are the same even though there is usually no history of overt overheating.  相似文献   
90.
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