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91.
Hartnack S Doherr MG Alter T Toutounian-Mashad K Greiner M 《Zoonoses and public health》2009,56(3):117-128
Campylobacter, a major zoonotic pathogen, displays seasonality in poultry and in humans. In order to identify temporal patterns in the prevalence of thermophilic Campylobacter spp. in a voluntary monitoring programme in broiler flocks in Germany and in the reported human incidence, time series methods were used. The data originated between May 2004 and June 2007. By the use of seasonal decomposition, autocorrelation and cross-correlation functions, it could be shown that an annual seasonality is present. However, the peak month differs between sample submission, prevalence in broilers and human incidence. Strikingly, the peak in human campylobacterioses preceded the peak in broiler prevalence in Lower Saxony rather than occurring after it. Significant cross-correlations between monthly temperature and prevalence in broilers as well as between human incidence, monthly temperature, rainfall and wind-force were identified. The results highlight the necessity to quantify the transmission of Campylobacter from broiler to humans and to include climatic factors in order to gain further insight into the epidemiology of this zoonotic disease. 相似文献
92.
Gupta RC Canerdy TD Lindley J Konemann M Minniear J Carroll BA Hendrick C Goad JT Rohde K Doss R Bagchi M Bagchi D 《Journal of animal physiology and animal nutrition》2012,96(5):770-777
The investigation was conducted on client-owned moderately arthritic dogs with two objectives: (i) to evaluate therapeutic efficacy of type-II collagen (UC-II) alone or in combination with glucosamine hydrochloride (GLU) and chondroitin sulphate (CHO), and (ii) to determine their tolerability and safety. Dogs in four groups (n = 7-10), were treated daily for a period of 150 days with placebo (Group-I), 10 mg active UC-II (Group-II), 2000 mg GLU + 1600 mg CHO (Group-III), and UC-II + GLU + CHO (Group-IV). On a monthly basis, dogs were evaluated for observational pain (overall pain, pain upon limb manipulation, and pain after physical exertion) using different numeric scales. Pain level was also measured objectively using piezoelectric sensor-based GFP for peak vertical force and impulse area. Dogs were also examined every month for physical, hepatic (ALP, ALT and bilirubin) and renal (BUN and creatinine) functions. Based on observations, significant (p < 0.05) reduction in pain was noted in Group-II, III, and IV dogs. Using GFP, significant increases in peak vertical force (N/kg body wt) and impulse area (N s/kg body wt), indicative of a decrease in arthritis associated pain, were observed in Group-II dogs only. None of the dogs in any group showed changes in physical, hepatic or renal functions. In conclusion, based on GFP data, moderately arthritic dogs treated with UC-II (10 mg) showed a marked reduction in arthritic pain with maximum improvement by day 150. UC-II, GLU and CHO operate through different mechanisms of action, and were well tolerated over a period of 150 days. 相似文献
93.
高粗料日粮中添加脂肪对奶年血液代谢产物瘤胃发酵和干物质消化率影响的研究 总被引:2,自引:0,他引:2
对50头泌乳中期的奶牛进行为期6周的饲养试验,研究高粗料高脂肪日粮对奶牛血液代谢产物、瘤胃发酵和干物质消化率的影响。试验设有10个重复,每个重复5头奶牛,每头奶牛给定一种日粮。试验用日粮为:对照日粮(日粮1)和试验日粮(高粗料75%高脂肪7.5%,日粮2;高粗料,中等水平脂肪5.0%,日粮3;中等水平粗料65%,高水平脂肪,日粮4;中等水平粗料和脂肪,日粮5;或者对照日粮中含有50%粗料和2.0%脂肪)。这些日粮含氮量相同(CP17.7%)。粗饲料由20苜蓿干草、40%苜蓿半干青贮和40%青贮玉米组成。所用脂肪由80%瘤胃 保护脂肪和20%黄色油脂组成。试验结果表明:试验组和对照组的血糖浓度差异不显著;试验组的血浆非酯化脂肪酸(NEFA)高于对照组。而奶牛采食日粮的粗饲料和脂肪水平不同,其NEFA差异不显著;对照组、试验组与粗饲料和脂肪水平不同的日粮的瘤胃PH、瘤胃VFA浓度和干物质消化率差异不显著。 相似文献
94.
OBJECTIVE: To isolate and characterize the eighth component of the complement system (C8) in cattle. SAMPLE POPULATION: Fresh plasma obtained from beef cattle. PROCEDURES: Plasma samples were fractionated, using sequential precipitation and ion-exchange and gel-filtration chromatography, to yield C8. The protein was identified throughout the procedure on the basis of its hemolytic function. Electrophoresis in polyacrylamide gels was used to determine molecular weight and composition of polypeptide chains. Reconstitution of classical and alternative complement pathways was used to characterize the hemolytic function of bovine C8. RESULTS: The bovine C8 protein consisted of a disulfide-bonded alpha-gamma heterodimer that was noncovalently associated with a beta chain. Apparent molecular weight of the alpha, beta, and gamma chains under reducing conditions were 66, 61, and 23 kd, respectively. In the classical pathway of activation, bovine C8 and the ninth component of the complement system (C9) had species incompatibility with human C8 and C9 on sheep erythrocyte target cells. CONCLUSIONS: A simple 4-step fractionation procedure provided good yield of bovine C8 from plasma. The isolated protein was structurally comparable to C8 from other species. Purified bovine C8 may be useful in functional hemolytic assays to investigate the roles of complement-mediated lysis in the pathogenesis of inflammatory diseases and the killing of susceptible microorganisms. 相似文献
96.
97.
98.
Chiba S Suzuki M Yamanouchi K Nishihara M 《The Journal of reproduction and development》2007,53(2):297-307
Recent studies have demonstrated the presence of neurogenesis in the adult mammalian hippocampus, and it has been suggested that estrogen and various growth factors influence the processes of adult neurogenesis. The present study assessed cell proliferation in the dentate gyrus and the mRNA expression levels of granulin, insulin-like growth factor-I (IGF-I), and brain-derived neurotrophic factor (BDNF) in the hippocampus 4 h after treatment with estradiol benzoate (EB) in 3- and 12-month old ovariectomized rats. At 3 months of age, mRNA expression of granulin precursor and cell proliferation were increased by EB treatment, although the mRNA expressions of IGF-I and BDNF remained unchanged. At 12 months of age, however, neither mRNA expression of the three genes nor cell proliferation in the dentate gyrus were affected by EB treatment. In addition, 17beta-estradiol enhanced the proliferation of neural progenitor cells derived from hippocampal tissue of 3-month-old female rats in vitro; this was inhibited by neutralization of granulin with specific antibody. These results suggest that estrogen induces granulin gene expression in the hippocampus and that the product of this gene is involved in the mitogenic effects of estrogen in the dentate gyrus, although the responses to estrogen decline with age. 相似文献
99.
Lamastra L Ferrari F Fait G Greco L Kennedy SH Capri E Trevisan M 《Pest management science》2011,67(11):1439-1445
BACKGROUND: 1,3‐Dichloropropene (1,3‐D, CAS No. 542‐75‐6) is a broad‐spectrum soil fumigant used to control numerous species of soilborne plant‐parasitic nematodes. 1,3‐D consists of two isomers, (Z)‐ and (E)‐1,3‐D. There are a number of low‐level chlorinated compounds that could potentially be produced as a part of the 1,3‐D manufacturing process. 1,3‐D and its metabolites, as well as potentially related chlorinated compounds, represent potential groundwater contaminants. RESULTS: This study has investigated the hydrolytic stability, under biotic and abiotic conditions in the laboratory, of an extensive representative list of 1,3‐D and potentially related chlorinated compounds in order to predict their environmental fate. All of these compounds showed intrinsic hydrolytic instability under both abiotic and biotic test conditions. Furthermore, a monitoring programme was carried out. Twenty‐five wells were monitored in five Italian regions characterised by historical and existing use of 1,3‐D. The parent compound, its two major metabolites and potentially related chlorinated compounds were not detected in the well water at > 0.1 µg L?1 at any sampling location. CONCLUSION: The soil fumigant (E,Z)‐1,3‐D, its metabolites and potentially related chlorinated compounds constitute a low risk to groundwater. Copyright © 2011 Society of Chemical Industry 相似文献
100.