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21.
Dichlorvos was applied as spray at 1 and 2% concentrations daily for a period of 28 and 21 consecutive days, respectively to buffalo calves. Animals sprayed with 1% dichlorvos displayed mild to moderate clinical signs of toxicosis during the 4th week of exposure. The higher concentration (2%) produced clinical signs of poisoning after 12-16 applications, and was lethal to one of three animals. Daily spraying of dichlorvos at both concentrations inactivated erythrocyte cholinesterase (ChE) (15-21%), plasma ChE (17-20%) and serum carboxylesterase (5-10%) within 3 days. The extent of inhibition of esterases was increased with repeated treatment and maximal inhibition of erythrocyte ChE (80-89%), plasma ChE (81-91%) and serum carboxylesterase (33-54%) with 1 and 2% concentrations was observed on the 28th and 21st day after start of application, respectively. In surviving animals, blood esterases remained inactivated to the extent of 14-65% on the 14th day after the termination of treatment. Dichlorvos at both concentrations significantly (P less than 0.01) elevated the serum levels of aspartate aminotransferase, alanine aminotransferase, acid phosphatase and alkaline phosphatase. The activities of these enzymes in surviving animals recovered to control values within 14 days after the final application of dichlorvos.  相似文献   
22.
In the phytophagous corn earworm, Helicoverpa (Heliothis) zea, females delay their reproductive behaviors until they find a suitable host on which to deposit their eggs. Perception of volatile chemical signals from corn silk triggers the production of sex pheromone followed by its release, which leads to mating. Several natural corn silk volatiles, including the plant hormone ethylene, induced pheromone production in H. zea females. Because H. zea larvae feed on the fruiting parts of a wide variety of hosts, ethylene, which is associated with fruit ripening, could act as a common cue.  相似文献   
23.
Recombinant fatty acid binding protein of Fasciola gigantica was expressed in Escherichia coli and purified by nickel chelating affinity chromatography. The recombinant protein along with native fatty acid binding protein (FABP) isolated from the parasite were evaluated for their potential in the diagnosis of F. gigantica infection in sheep, cattle and buffaloes, both by ELISA and western blotting. Results of this study indicate that there is no humoral immune response generated against this protein in the experimental infection of these ruminants with F. gigantica, thereby limiting the usefulness of this antigen in the early diagnosis of fasciolosis in these animals. Also, the paper discusses the probable reasons for the failure of this protein in detecting humoral response in these animals by ELISA and immunoblotting.  相似文献   
24.
The immunogenicity of a sonicated extract (SE) and of outer membrane proteins (OMP) of Salmonella enteritidis was tested in birds of about 8 weeks of age. The dose, route of vaccination and the adjuvant used varied in different groups of birds. Two vaccine doses with or without adjuvant were given parenterally or orally 3 weeks apart. OMP vaccines gave significantly higher antibody titres than SE vaccines, as indicated by ELISA. The vaccines adjuvanted with oil produced higher antibody titres than those without any adjuvant. A dose of 1 mg of vaccine produced higher antibody titres than 0.5 mg of vaccine. Adjuvanted vaccine given subcutaneously elicited higher antibody responses than oral vaccines given without adjuvant. The birds were challenged with virulent S. enteritidis organisms at the end of the second week after a booster dose. None of the birds given 1 mg of OMP vaccine subcutaneously shed the organisms when tested by culturing cloacal swabs, although a few birds vaccinated with 0.5 mg of OMP vaccine did so. In general, adjuvanted OMP vaccines gave better protection than SE vaccines.  相似文献   
25.
Linking long-term dietary patterns with gut microbial enterotypes   总被引:1,自引:0,他引:1  
Diet strongly affects human health, partly by modulating gut microbiome composition. We used diet inventories and 16S rDNA sequencing to characterize fecal samples from 98 individuals. Fecal communities clustered into enterotypes distinguished primarily by levels of Bacteroides and Prevotella. Enterotypes were strongly associated with long-term diets, particularly protein and animal fat (Bacteroides) versus carbohydrates (Prevotella). A controlled-feeding study of 10 subjects showed that microbiome composition changed detectably within 24 hours of initiating a high-fat/low-fiber or low-fat/high-fiber diet, but that enterotype identity remained stable during the 10-day study. Thus, alternative enterotype states are associated with long-term diet.  相似文献   
26.
OBJECTIVE: To determine rate and degree of cooling for the superficial digital flexor tendon (SDFT) during a standard cryotherapy application in horses and evaluate in vitro effects of cooling on survival of tendon cells. SAMPLE POPULATION: 6 limbs of 5 adult horses and cultured cells obtained from SDFT of 3 adult horses during necropsy. PROCEDURE: In vivo data were acquired by use of a thermocouple temperature probe inserted into the SDFT of a forelimb of each standing sedated horse. After baseline temperatures were recorded, a commercial compression splint with circulating coolant was placed on each selected limb, which was then exposed to cold treatment for 60 minutes. Temperatures were recorded at 30-second intervals. Mean minimum core temperature was calculated and used to design a protocol for in vitro cold treatment of cells. Specimens were obtained from the SDFT of horses during necropsy; tendon cells were cultured in suspension and exposed to 1-hour of cold treatment that mimicked the in vivo procedure. Viability of cells after cold treatment was compared with viability of cells maintained at body temperature. RESULTS: After 1 hour of cold treatment, SDFT core temperature was reduced by a mean of 21.8 degrees C, reaching a mean minimum temperature of 10 degrees C. Viability did not differ significantly between cold-treated and control cells. CONCLUSION AND CLINICAL RELEVANCE: Results indicated that topical application of cryotherapy significantly reduced core SDFT temperature in standing sedated horses. Temperatures achieved in vivo during cold treatment were not detrimental to the in vitro viability of tendon cells.  相似文献   
27.
We evaluated the pharmacokinetics of ciprofloxacin in serum (n = 6) and urine (n = 4) in goats following a single intravenous administration of 4 mg/kg body weight. The serum concentration-time curves of ciprofloxacin were best fitted by a two-compartment open model. The drug was detected in goat serum up to 12 h. The elimination rate constant (β) and elimination half-life (t1/2β) were 0.446 ± 0.04 h-1 and 1.630 ± 0.17 h, respectively. The apparent volume of distribution at steady state (Vdss) was 2.012 ± 0.37 l/kg and the total body clearance (ClB) was 16.27 ± 1.87 ml/min/kg. Urinary recovery of ciprofloxacin was 29.70% ± 10.34% of the administered dose within 36 h post administration. In vitro serum protein binding was 41% ± 13.10%. Thus, a single daily intravenous dose of 4 mg/kg is sufficient to maintain effective levels in serum and for 36 h in urine, allowing treatment of systemic, Gram-negative bacterial infections and urinary tract infections by most pathogens.  相似文献   
28.
Repeat unit length variation and internal transcribed spacer (ITS) sequences of nuclear ribosomal DNA were used to assess genetic diversity, and phylogenetic relationships in chickpea (C. arietinum) cultivars, and its related wild species. Total genomic DNAs of 76 accessions of 10 Cicer species, belonging to three sections of the genus, were restricted with seven enzymes and the restriction fragments were hybridized to heterologous ribosomal clones of wheat pTa71 and Vicia faba probes Ver 6-5 and Ver18-6. A single repeat unit length class of 11.4 kb or 10.5 kb was recognized across Cicer accessions with pTa71. The intraspecific variation was negligible in those species where more than one accession was studied, except the four C. judaicum accessions, which were different from the rest. EcoRI and DraI digests gave two and one-two fragments, respectively. All the accessions produced three and three-five bands with BamHI and SacI, respectively. Both the accessions of C. yamashitae differed in their rDNA repeat unit length as well as restriction site variation. Maximum likelihood tree with rDNA RFLP recognized five clades which were more or less congruent with the previous data. Length of ITS-1 region was more variable (235–239 bp) than the ITS-2 region (212–213 bp). Cladistic analysis of ITS data revealed two major clades, clade I consisting of C. arietinum, C. reticulatum and C. echinospermum, and clade II comprised of C. judaicum, C. chorassanicum, C. bijugum and C. cuneatum. C. microphyllum grouped with the above four species. C. pinnatifidum was present as a separate branch. C. yamashitae emerged as the most distinct species.  相似文献   
29.
OBJECTIVE: To estimate the potential impact of zinc biofortification of rice and wheat on public health in India and to evaluate its cost-effectiveness compared with alternative interventions and international standards. DESIGN: The burden of zinc deficiency (ZnD) in India was expressed in disability-adjusted life years (DALYs) lost. Current zinc intakes were derived from a nationally representative household food consumption survey (30-day recall) and attributed to household members based on adult equivalent weights. Using a dose-response function, projected increased zinc intakes from biofortified rice and wheat were translated into potential health improvements for pessimistic and optimistic scenarios. After estimating the costs of developing and disseminating the new varieties, the cost-effectiveness of zinc biofortification was calculated for both scenarios and compared with alternative micronutrient interventions and international reference standards. SETTING: India. SUBJECTS: Representative household survey (n = 119 554). RESULTS: The calculated annual burden of ZnD in India is 2.8 million DALYs lost. Zinc biofortification of rice and wheat may reduce this burden by 20-51% and save 0.6-1.4 million DALYs each year, depending on the scenario. The cost for saving one DALY amounts to $US 0.73-7.31, which is very cost-effective by standards of the World Bank and the World Health Organization, and is lower than that of most other micronutrient interventions. CONCLUSIONS: Not only may zinc biofortification save lives and prevent morbidity among millions of people, it may also help accommodate the need to economise and to allocate resources more efficiently. Further research is needed to corroborate these findings.  相似文献   
30.
Andrographis paniculata [(Burm. f.) Wall. ex Nees, family Acanthaceae], commonly known as kalmegh is used both in Ayurvedic and Unani system of medicines for a number of ailments related to digestion, hepatoprotection, hypoglycaemic and as anti-bacterial, analgesic, anti-inflammatory, vermicidal and antipyretic. Although kalmegh is extensively used in Indian Systems of Medicine, but it is not yet cultivated on a large-scale. The supply of herb is met from the wild growing populations which is now under constrain due to over-collection. Considering its value as a drug raw material, genetic variability of A. paniculata was augmented from different geographical regions of India by explorations and was conserved at the National Gene Bank, NBPGR, New Delhi. The therapeutic activity of the herb has been attributed to andrographolide, a bicyclic diterpenoid lactone present in the whole herb. Thirty germplasm collections of A. paniculata were evaluated for bioactive compound andrographolide to find out superior genotype for high drug yield. The andrographolide content in the germplasm was quantitatively analyzed by high performance thin-layer chromatography (HPTLC) at 232 nm. Results indicated wide variability among thirty accessions of A. paniculata for andrographolide content which ranged from 0.72 to 2.99 % on dry weight basis. DIVA-GIS analysis of A. paniculata germplasm for andrographolide content showed that diverse accessions of A. paniculata exist in three Indian states of Orissa, Tamil Nadu and Kerala. Promising accessions having high andrographolide content were identified; IC520361 (2.99 %), IC520395 (2.86 %), IC399125 (2.81 %), IC369404 (2.77 %) and IC520394 (2.61 %). Due to the economic importance of the drug, these promising collections can be exploited for large-scale cultivation for their pharmacologically important constituents mainly andrographolide content and also can serve as potential source for breeding and improvement of cultivars for obtaining higher drug yield.  相似文献   
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