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91.
Simple catalytic models were used for estimating the true incidence of malaria in hyperendemic villages of Koraput District in Orissa State where Plasmodium falciparum is predominant. The hill top villages recorded a slide positive rate of 45.68. The daily rate of inoculation among infants was estimated to be 0.00781. The inoculation rate was so high that the recovery from one infection was compensated by the subsequent infection and hence the prevalence continued to increase with age. The model adequately represents the observed data for infants but could not be used for estimating the true prevalence in the adult population without incorporating other factors like immunity and superinfection. 相似文献
92.
Mutations of the p53 gene are associated with a number of non-lymphoid cancers of the dog. The present study investigates the p53 gene status within canine patients treated for primary and secondary lymphoma. Three out of eight patients exhibited p53 gene mutations. These included one patient with a germ line mutation and two patients with de novo p53 mutations associated with the secondary lymphoma. Allelic loss of the p53 gene was also observed within primary and secondary tumours of the three canine patients. The results indicate that germ line p53 mutations exist in dogs and may be involved in the known predisposition of some breeds to cancer. The presence of therapy-related p53 point mutations was found to be associated with chemoresistant secondary lymphomas. A causative role for DNA-damaging chemotherapy in de novo mutation of the p53 gene is discussed. Characterization of p53 inactivation in canine tumorigenesis may provide a valuable clinical model for assessing the efficacy and optimal therapeutic regimens of anti-cancer agents. 相似文献
93.
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95.
A net energy analysis of district solar heating using seasonal heat storage has been performed. The use of seasonal heat storage is of great importance in northern latitudes when the solar contribution is to be increased. Different system alternatives were considered. Net energy ratios for the most favourable options were found to be between 3 and 5. 相似文献
96.
A microorganism of the genus Pseudomonas has been isolated from the soil by enrichment culture techniques with linalool(I) as the sole source of carbon and energy. The organism is also capable of utilizing limonene, citronellol, and geraniol as substrates but fails to grow on citral, critranellal, and 1,8-cineole. Fermentation of linalool by this bacterium in a mineral salt medium results in the formation of 10-hydroxylinalool(II), oleuropeic acid (IX), 2-vinyl-2-methyl-5-hydroxyisopropyl-tetraphydrofuran)linalool oxide, V), 2-vinyl-2-methyl-tetrahydrofuran-5-one(unsaturated lactone, VI), and few unidentified minor metabolities. Probable pathways for the biodegradation of linalool are presented. 相似文献
97.
Soren Damgaard-Larsen Kirsten Ottar Jensen Ebba Lund Birte Nissen 《Water research》1977,11(6):503-508
Coxsackievirus and tritiated water were added to municipal sludges which were placed on lysimeters containing sandy soil or clay soil. It took 23 weeks during a normal Danish winter to inactivate virus from an initial 106tcid50/g sludge to a not demonstrable level. Irrespective of sludge and soil type no virus was demonstrated in the leachate water. The rainfall during December–May was 300 mm. 相似文献
98.
The primary aim of this study was to evaluate the phenotypic and genetic trends for stillbirth in Danish Holsteins. Trends of calving difficulty and calf size were also evaluated. The second aim was to compare predicted transmitting abilities (PTA) of sires for stillbirth using a linear and a threshold model. Direct and maternal genetic effects were modeled by fitting correlated additive genetic effects of the sire and the maternal grandsire (MGS). For both the calf and the dam, covariates of breed proportions of Holstein-Friesian (HF) and the heterozygosity between HF and the original Danish Black and White (ODBW) were included. Records from 1.8 million first-calving Danish Holstein cows calving from 1985 to 2002 were used. In this period, the overall frequency of stillbirth increased from 0.071 to 0.090. An unfavorable genetic trend of stillbirth was found for both the direct and maternal effect. The background for the genetic trends was an intense use of HF sires as sires of sons, which increased the proportion of HF genes to 94% in the Danish Holstein calves born in 2002. The effect of the imported HF genes was higher direct effects of calf size, calving difficulty, and stillbirth compared with the ODBW genes. The maternal effect of stillbirth was poorer for HF than for ODBW even though HF had a better maternal calving performance than ODBW. The threshold and the linear models showed almost similar predictions of transmitting abilities of sires. 相似文献
99.
100.