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Measurements of stratospheric carbon dioxide (CO2) and nitrous oxide (N2O) concentrations were analyzed to investigate stratospheric transport rates. Temporal variations in tropospheric CO2 were observed to propagate into the stratosphere, showing that tropospheric air enters the lower tropical stratosphere continuously, ascends, and is transported rapidly (in less than 1 month) to both hemispheres. The mean age A of stratospheric air determined from CO2 data is approximately 5 years in the mid-stratosphere. The mean age is mathematically equivalent to a conserved tracer analogous to exhaust from stratospheric aircraft. Comparison of values for A from models and observations indicates that current model simulations likely underestimate pollutant concentrations from proposed stratospheric aircraft by 25 to 100 percent.  相似文献   
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江苏省GSP试点工作通过加强组织领导、广泛宣传推动、强化培训指导和注重检查交流等措施,基本建立了兽药GSP制度的框架,进一步提高和统一了对兽药GSP的认识,提高了试点企业的质量管理水平。但在兽药GSP实施过程中,存在对其重要性认识不足,部分暂行管理办法内容与实际脱节,技术指导力量薄弱等问题。  相似文献   
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Raghavendran HR  Rekha S  Cho HK  Jang SS  Son CG 《Fitoterapia》2012,83(6):1144-1150
Panax ginseng is an indigenous medicinal herb and has traditionally been used among Asian population for relief of many human ailments. We investigated the prophylactic role of Korean P. ginseng extract (KG) against X-ray irradiation-induced emesis in an acute rat pica model. Rats were treated with KG (12.5, 25, 50 mg/kg orally at -48, -24 and 0 h) prior to X-ray irradiation (6 Gy), and intake of kaolin and normal food and body weight changes examined as an index of the acute emetic stimulus. Levels of serotonin in small intestine tissue were assessed and histopathology of gastric tissue, small intestine and colon examined specific staining. Pre-treatment with KG (12.5 and 25 mg/kg) reduced X-ray irradiation-induced kaolin intake at 24h. Normal food intake was improved in rats treated with 25 mg/kg KG. The anti-emetic effect of KG was further confirmed on the basis of serotonin release, histopathological findings. Our findings collectively indicate that KG protects against X-ray irradiation-induced acute pica to a moderate extent, leading to improved feeding behavior in rats.  相似文献   
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Post‐partum period has an important role in cows' breeding due to its effects on reproductive efficiency and subsequent pregnancy. Escherichia coli, Trueperella pyogenes (Arcanobacterium pyogenes), Fusobacterium necrophorum and Prevotella melaninogenicus are recognized as major pathogens associated with uterine endometrial lesions. The objective of this study was to identify these pathogens using the polymerase chain reaction (PCR) as a culture‐independent sensitive method. A total of 172 cows were examined 25–35 days post‐partum, and 128 cows were examined at 2 weeks later (39–49 days post‐partum). Uterine discharges were collected by covered plastic infusion pipettes. The prevalence of endometritis was greater in the first examination than the second (35.5% vs. 16%). E. coli was detected in eight of the samples, T. pyogenes was detected in 13 of the samples and F. necrophorum was detected in 11 of the samples. There was no positive sample of P. melaninogenicus. Uterine contamination by T. pyogenes and F. necrophorum in the first examination was higher than the second examination. T. pyogenes affected as a tendency the prevalence of clinical endometritis in first examination. Primiparous cows showed 4.02 times higher odds of clinical endometritis compared with second‐parity cows in first examination. A multiplex PCR protocol as a simple, less expensive, fast assay was introduced to identify E. coli, T. pyogenes and F. necrophorum.  相似文献   
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目前,禽病防疫仍以疫苗免疫接种为主,疫苗安全性直接影响疫病防控效果,优质疫苗能预防疾病,提高家禽的生产性能,创造经济效益。相反,劣质疫苗可能对动物造成伤害,对环境造成污染,乃至威胁人类的健康。因此,选择安全高效的优质疫苗是做好家禽疫病防疫的关键。为保证疫苗质量安全,实行禽用活疫苗SPF化已经势在必行。  相似文献   
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Central bearded dragons (Pogona vitticeps) are one of the most popular reptile pets in Australia and around the world. Diseases, including metabolic bone disease, periodontal disease, and gastrointestinal endoparasites commonly affect captive animals. To determine the common reasons these lizards were presented to the veterinarian and to establish the prevalence of disease seen in captive P. vitticeps in Australia, this retrospective study evaluated the clinical records of three exotic pet veterinary hospitals. Records from 724 P. vitticeps were analysed, with 70 reasons for presentation and 88 diseases identified across 1000 visits to the veterinarian. Lethargy was the most reported reason for presentation (n = 181). The gastrointestinal tract (18.25%) and skin (18.25%) were the equally most commonly affected organ systems, followed by the musculoskeletal system (15.17%). Endoparasites were the most common single disease process (n = 103), followed by metabolic bone disease (n = 65), skin wounds (n = 59) and periodontal disease (n = 48). Of the patients that presented for routine preventive health examinations (n = 159), 45.30% received some form of intervention to treat or prevent disease. Many of the conditions that were identified by the veterinarians in this study are traditionally correlated with suboptimal husbandry and may be easily prevented. This study identified the common reasons for presentation to the veterinarian and the prevalence of disease in captive P. vitticeps in Australia, providing the first extensive retrospective analysis of objective reference literature for central bearded dragon owners and aspiring reptile veterinarians.  相似文献   
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OBJECTIVE: To assess a ready-to-use formulation of dicyclanil to prevent blowfly strike on Merino sheep under Australian conditions. DESIGN: Randomised clinical trials conducted in an environment house and in the field. PROCEDURE: Two environment house trials were used to measure the protection against flystrike provide by a jetting or a ready-to-use 5% spray-on formulation of dicyclanil over 22 and 31 weeks respectively. Oviposition and strikes were recorded weekly for each sheep. In two field trials the occurrence of strike in Merino sheep treated off-shears or in long wool with dicyclanil or with cyromazine was compared for up to 38 weeks after treatment. Efficacy was assessed by calculating the cumulative percentage of sheep struck. RESULTS: Under environment house conditions, sheep jetted with dicyclanil at 1.50, 0.75 and 0.30 g per sheep developed 0, 8 and 9 strikes respectively during the 22 weeks of the trial, whereas there were 358 strikes present in the placebo group. Sheep sprayed with dicyclanil at 2.25, 1.50 and 0.75 g per sheep developed 5, 11 and 29 strikes respectively between weeks 15 and 31 after treatment, whereas there were 185 strikes present in the untreated controls. In field trials the cumulative percentage of sheep struck reached 1% between weeks 12 to 13 after sheep had been treated with cyromazine. Sheep treated with dicyclanil reached the 1% limit at week 21 after treatment. CONCLUSION: Under Australian field conditions, a ready-to-use 5% spray-on formulation of dicyclanil applied off-shears or to long wool protected Merino sheep from blowfly strike for a period of at least 20 weeks.  相似文献   
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