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411.
Oviposition, egg hatching and survival of newly-hatched larvae of Boophilus annulatus were studied in relation to infection by Babesia species and different temperature regimens. Infection of female ticks by Babesia bigemina or B. bovis had no effect on the time elapsed between engorgement and oviposition. The duration of oviposition was shorter in infected females incubated at 25 degrees C or 35 degrees C and infected females laid fewer eggs than the controls. No larvae hatched at 16 degrees C. B. bigemina-infected eggs hatched more quickly than uninfected eggs at 35 degrees C. The hatching percentage of B. bigemina-infected eggs was reduced by 50% at an incubation temperature of 25 degrees C and by 75% at 35 degrees C. At 16 degrees C there was no difference in the duration of survival of infected and non-infected larvae but at 25 degrees C and 35 degrees C the mean survival period of infected larvae was significantly lower than those of controls.  相似文献   
412.
413.
The present study analyses the energy budget of crop production in hill agro-ecosystems and discusses the relation between agro- and natural ecosystems. The cultivated area is divisible according to cropping pattern into (I) vegetable-based patterns and (II) wheat-based patterns. The values of input and output, in terms of energy, indicated minimum input for the wheat-soybean and maximum input for potato-cabbage-potato patterns among all cropping patterns. 1·7 times more output of energy is generated in vegetable-based ecosystems with an input of 25 times as much fertilizer, 151 times as much manure, 6 times as much seed and 6 times as much human labour as in the wheat-based system. Hill agriculture depends to a great extent on the surrounding forest ecosystem and represents centres of massive energy consumption.  相似文献   
414.
Clinical trials were carried out on 3 groups of 30 Friesian cattle naturally infected with Trichophyton verrucosum. One group was treated with 3.75% thiabendazole in glycerine, another with 5% tincture of iodine and the last served as the control group without any treatment. Both the preparations were applied locally on the ringworm lesions at 3 day intervals with a total of 4 applications. The percentage of animals cured was 86.7 by thiabendazole and 46.7 by tincture of iodine. No recrudescence was observed during the subsequent 4 months period.  相似文献   
415.
416.
The rice field herbicide, propanil, was toxic to the nitrogen-fixing cyanobacterium Nostoc calcicola. A decrease in growth was observed with the increasing concentrations of propanil, 30 μg/ml being lethal. Since toxicity of the herbicide could be reversed by exogeneous supplementation of assimilable organic carbon glucose, it is suggested that carbon fixation was sensitive to the herbicide. The herbicide inhibited heterocyst differentiation and nitrogen fixation. There was a rapid decrease in total protein, nucleic acids (DNA, RNA), and carbohydrate content accompanied by a loss of photosynthetic pigments. The phycocyanin: chlorophyll a ratio showed positive correlation with increased dosages of the herbicide, suggesting the inhibition of chlorophyll a.  相似文献   
417.

Background

In women with breast cancer submitted to neoadjuvant chemotherapy based in doxorubicin, tumor expression of groups of three genes (PRSS11, MTSS1, CLPTM1 and PRSS11, MTSS1, SMYD2) have classified them as responsive or resistant. We have investigated whether expression of these trios of genes could predict mammary carcinoma response in dogs and whether tumor slices, which maintain epithelial-mesenchymal interactions, could be used to evaluate drug response in vitro.

Methods

Tumors from 38 dogs were sliced and cultured with or without doxorubicin 1 μM for 24 h. Tumor cells were counted by two observers to establish a percentage variation in cell number, between slices. Based on these results, a reduction in cell number between treated and control samples ≥ 21.7%, arbitrarily classified samples, as drug responsive. Tumor expression of PRSS11, MTSS1, CLPTM1 and SMYD2, was evaluated by real time PCR. Relative expression results were then transformed to their natural logarithm values, which were spatially disposed according to the expression of trios of genes, comprising PRSS11, MTSS1, CLPTM1 and PRSS11, MTSS1, SMYD2. Fisher linear discrimination test was used to generate a separation plane between responsive and non-responsive tumors.

Results

Culture of tumor slices for 24 h was feasible. Nine samples were considered responsive and 29 non-responsive to doxorubicin, considering the pre-established cut-off value of cell number reduction ≥ 21.7%, between doxorubicin treated and control samples. Relative gene expression was evaluated and tumor samples were then spatially distributed according to the expression of the trios of genes: PRSS11, MTSS1, CLPTM1 and PRSS11, MTSS1, SMYD2. A separation plane was generated. However, no clear separation between responsive and non-responsive samples could be observed.

Conclusion

Three-dimensional distribution of samples according to the expression of the trios of genes PRSS11, MTSS1, CLPTM1 and PRSS11, MTSS1, SMYD2 could not predict doxorubicin in vitro responsiveness. Short term culture of mammary gland cancer slices may be an interesting model to evaluate chemotherapy activity.  相似文献   
418.
The study aimed to understand the root morphological character of 1 year old seedling rootstock of citrus genotypes viz., rough lemon, Karna Khatta, Carrizo citrange, Rangpur lime, Troyer citrange, Jatti Khatti and sour orange as well as to investigate the effect of these rootstocks on the leaf mineral composition of Kinnow. Root morphological traits showed significant genotypic variation. Rough lemon seedlings had a higher root length, projected area, surface area, volume and the number of forks. Sour orange was moderate rootstock of the 7 genotypes for most of the root morphological characters, while citrange rootstocks expressed poor root morphology. The rootstocks also imparted significant influence on the leaf mineral composition. Leaf K, Ca and Mg content was recorded maximum in plants grown on rough lemon seedling, while N, P, Fe, Zn, Mn and Cu concentration was higher on sour orange rootstock. Kinnow trees on Rangpur lime rootstock accumulated more Na in their leaf tissue, where as Troyer citrange restricted the accumulation of Na. Considering the root morphological characters and nutrient accumulation pattern, rough lemon and sour orange for areas free from tristeza virus could be suggested as alternative rootstocks for the studied Kinnow mandarin under similar ecological conditions.  相似文献   
419.
The study was designed to evaluate the influence of season on semen characteristics and seminal plasma protein profile of buffalo bull semen. Thirty‐six ejaculates were collected in three seasons (winter, summer and rainy) from six adult Bhadawari bulls, and semen characteristics were evaluated immediately after collection. The seminal plasma was harvested by centrifugation and protein profiling, and percentage protein fractions were analysed by SDS‐PAGE. The significant effect of season was observed on ejaculate volume, sperm concentration, progressive motility, percentage live spermatozoa, hypo‐osmotic swelling test (HOST) and acrosomal integrity. The electrophoretogram of seminal plasma proteins revealed 20 protein bands in winter, 23 bands in rainy and 25 bands in summer seasons, illustrating the significant effect of seasons on seminal plasma proteins. Among these protein bands, 18 bands were observed common in semen samples of all three seasons while protein bands of 46, 55, 58, 144 and 160 kDa were found in rainy and summer seasons. The protein bands of 48 and 60 kDa were observed only in winter season, whereas 184 and 200 kDa were reported in summer season only. The protein fractions (protein%) of common protein bands observed in three seasons revealed a significant effect of season on protein bands of 24.5, 66, 70, 72, 84 and 86 kDa. From the study, it was pertinent that bull seminal plasma contains specific proteins in particular season, which may be associated with some of the semen characteristics, and these proteins could be used as markers of the semen quality of buffalo bulls.  相似文献   
420.
Particularly in developing countries, forests provide feed for livestock in the form of fodder for stall-feeding and grazing in forest areas. Extraction of fodder resources from forests often leads to forest degradation. An attempt has been made to qualify extend of biomass extraction from forests and to compare forest fodder dependence of households in a number of forest density classes in the mountainous region of Himalayas, in Uttarakhand state in India, according to livestock owners’ perspectives. Information was obtained from a survey of livestock feed and fodder collection and utilization from 316 randomly selected households distributed across four government-defined forest density classes, namely very dense forest, moderately dense forest, open forest and scrub. Households obtained feed and fodder for livestock from three sources, i.e. forest areas, non-forest areas and local markets. Daily feed consumption per adult cattle unit varied according to source, ranging from 9.85 to 14.70 kg from forest areas, 7.40 to 11.14 kg from non-forest areas, and less than 1 kg from local markets. The dependency of households on fodder for livestock differed significantly between households located in each forest density classes. The current forest fodder extraction rate is likely to be unsustainable. Measures identified to reduce the extraction rate include greater use of alternative fodder sources and managing small patches of the natural forests adjoining dependent villages for fodder production through community participation.  相似文献   
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