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1.
After application of [14C]lindane to the nutrient medium (1.45 ppm), 14.1% of the radioactivity was taken up by 12 lettuce plants during 4 weeks; in the nutrient medium, 7.8% was recovered after the same time interval. The radioactivity in the nutrient extract comprised: unchanged lindane (about 82%); free 2,3,4,6-tetrachlorophenol, free pentachlorophenol, conjugates of pentachlorophenol, and an unidentified polar compound (a total of 15%); 1,2,3-trichlorobenzene, 1,2,3,4-tetrachlorobenzene, pentachlorobenzene, hexachlorobenzene, 2,3,4,5,6-pentachlorocyclohex-1-ene, and probably 1,2,3,4,5,6-hexachlorocyclohexene (a total of 3%). The radioactivity extracted from plants consisted of unchanged lindane (about 77%); free 2,3,4,6-tetrachlorophenol, conjugates of a tetrachlorophenol and pentachlorophenol, and a strongly hydrophilic compound that was not identified (a total of 20%); 1,2,3-trichlorobenzene, 1,2,4-trichlorobenzene, pentachlorobenzene, 2,3,4,5,6-pentachlorocyclohex-1-ene, and probably 1,2,3,4,5,6-hexachlorocyclohexene (a total of 3%). Identification was carried out by means of comparisons of chromatographic properties and of the mass spectra with those of authentic reference compounds. The significance of hexachlorobenzene as a metabolite of lindane is discussed.  相似文献   
2.
Numerous culture-based diagnostics are available on the Australian and international markets for on-farm detection of bacterial pathogens in milk. Use of such diagnostics may provide an opportunity to improve the prudent use of antimicrobials in udder health management. Farms are low-resource settings in terms of diagnostic microbiology capacity. The World Health Organisation has identified criteria for the evaluation of diagnostic tests in low resource settings based on Accuracy, Sensitivity, Specificity, User-friendliness, being Rapid or Robust, Equipment-free and being Deliverable (ASSURED). Here, we review how those criteria can be interpreted in the context of microbiological diagnosis of mastitis pathogens, and how on-farm diagnostics that are currently available in Australia perform relative to ASSURED criteria. This evaluation identifies multiple trade-offs, both with regard to scientific criteria and with regards to convenience criteria. More importantly, the purpose of testing may differ between farms, and test performance should be evaluated relative to its intended use. The ability of on-farm mastitis diagnostics to inform mastitis treatment decision-making in a timely and cost-effective manner depends not just on test characteristics but also on farm-specific pathogen prevalence, and on the farm enterprise's priorities and the farm manager's potential courses of action. With most assay evaluations to date conducted in professional laboratories, there is a surprising dearth of information on how well any of the diagnostic tests perform on-farm and, indeed, of the on-farm decision-making processes that they aim to inform.  相似文献   
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TREATMENT OF DIAPHRAGMATIC HERNIA IN BUFFALOES   总被引:2,自引:0,他引:2  
The surgical treatment of diaphragmatic hernia attempted on 19 lactating buffaloes is described. Thirteen cases recovered uneventfully, 1 recovered after developing brisket oedema and 5 died, 3 during surgery and 2 postoperatively. The desired depth of anaesthesia was achieved by the administration of 6% chloral hydrate followed by 5% thiopentone sodium. A postxiphoid approach and the use of a continuous lock stitch suture were preferred to repair the vent in the diaphragm. Pre- and post-operative use of hydrocortisones and fluids and sufficient tissue oxygenation by controlled positive pressure respiration are believed to be keys to the success of the treatment adopted.  相似文献   
5.
Objective To measure plasma cortisol responses in calves dehorned using a scoop after administration of local anaesthesia and/or cautery of the wounds.
Design A physiological study with controls.
Procedure There were six treatments: control handling with and without local anaesthesia, dehorning, dehorning after local anaesthesia, dehorning followed by wound cautery, and dehorning after local anaesthesia followed by wound cautery. Blood samples were taken before and after dehorning.
Results Dehorning caused an increase in plasma cortisol concentrations, which decreased a little to plateau values and then declined to pretreatment values 3 to 4 h after dehorning. The peak was smaller after local anaesthesia was administered but when its effects wore off, cortisol concentrations increased and thereafter were similar to those in the dehorned animals. The combination of local anaesthesia and cautery resulted in a plasma cortisol response similar to those in control calves with or without local anaesthesia.
Conclusions If plasma cortisol concentrations reflect the distress being experienced by the calves, then local anaesthesia reduces the acute distress for about 3 h after dehorning but not during the subsequent 3 to 4 h. Combining local anaesthetic and cautery prevented the significant increase in plasma cortisol following dehorning and may eliminate the acute distress caused by scoop dehorning.  相似文献   
6.
A study conducted to assess the floor vegetation shows the presence of 17 species underPopulus deltoides in comparison to 28, 29 and 35 underAlbizia lebbeck, Dalbergia sissoo and mix-culture plantations, respectively. Further, the biomass and density of floor vegetation is considerably reduced underP. deltoides compared to other plantations. In addition, the indices for species richness, evenness, dominance and diversity are also reduced underP. deltoides showing some inhibitory mechanism being operative under these plantations. Based on available literature, allelopathy is speculated to be responsible for this reduction.  相似文献   
7.
Perilipins have been reported to limit the interaction of lipases with neutral lipids within the droplets, thereby regulating neutral lipid accumulation and utilization. This study aimed to identify the location and expression of PLIN1 and PLIN2 in porcine oocytes during maturation. Quantitative real‐time polymerase chain reaction (qRT‐PCR), immunostaining and Western blot methods were used to characterize the expression and distribution patterns of PLIN1 and PLIN2 in porcine oocytes. The results showed that PLIN1 was not detectable in porcine oocytes. PLIN2 and BODIPY 493/503‐detected neutral lipid droplets appeared identical distribution patterns and extensive colocalization in both GV and MII porcine oocytes. PLIN2 protein expression was higher in GV oocytes than that in MII oocytes (p < 0.05), although PLIN2 mRNA expression was similar in both groups. These findings suggested that PLIN2 was a major lipid droplet‐associated protein in porcine oocytes.  相似文献   
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9.
Field and laboratory experiments were carried out to describe the effects of Aporrectodea nocturna on soil characteristics in a pre-alpine meadow and to support the development of a model of cast production. In the prealpine meadow, increased cast production, first observed about 20 years ago around a newly planted hedge, was recorded to a distance of maximal 170 m from the hedge. Numbers of A. nocturna between 130 and 165 m from the hedge decreased from 164 to 16 individuals m-2. In the same area cast production steadily decreased from about 1.5 kg m-2 week-1 to nil, the plant community structure changed and the microbial biomass decreased, but the root biomass and the moisture content did not change. Laboratory experiments demonstrated that high cast production was not a specific feature of the A. nocturna population nor of the soil in the meadow. Diapause of A. nocturna was terminated in the laboratory during September. A model of cast production potential by the earthworm A. nocturna was established using laboratory determinations of the relationships with body weight, temperature, and water potential. The model was shown to predict cast production in the field given the assumption that the water potential was 0 MPa. According to the model, 81% of surface cast production was by juveniles, and 19% by adults of A. nocturna.  相似文献   
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