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101.
CA O'Leary DL Duffy MA Gething C McGuckin JS Rand 《New Zealand veterinary journal》2013,61(6):354-358
AIM: To investigate, in a pilot study, a possible genetic component to type 2 diabetes mellitus (T2D) in Burmese cats in New Zealand by analysing pedigree data.METHODS: Pedigrees were obtained for 305 Burmese cats living in New Zealand; diabetes was diagnosed in 19 of these due to presence of polyuria and polydipsia, persistent concentrations of glucose in plasma >16?mmol/L and glucosuria prior to insulin treatment. Pedigrees were also submitted for 16 cats with no clinical signs of T2D. The remaining 270 cats were unobserved relatives of these individuals. Inbreeding coefficients and heritability were calculated, and a single major locus model segregation analysis was conducted using pedigree analysis software.RESULTS: Nineteen cats were diagnosed with T2D. Males (n = 14) and females (n = 5) were both affected, suggesting that the gene or genes causing diabetes are autosomal rather than sex-linked. Examination of the pedigree revealed few signs of fully penetrant dominant gene action: diabetes was ostensibly rarely seen in sequential generations and nearly always skipped at least one and often more generations; apparently unaffected offspring of apparently unaffected parents sometimes produced affected progeny. The mean relatedness of the affected animals within the core pedigree (16 diabetic cats) was 0.049, and mean inbreeding 0.033. Based on 100,000 permutations of the trait values, the expected relatedness of a random sample of 16 animals taken from the phenotyped animals would be 0.013 (SD 0.007) (permutation p = 0.0009). The observed inbreeding was also significant (permutation p= 0.02).Heritability was estimated to be 9 (95% CI = 0–57)% assuming all animals with unknown status were unaffected. The best fitting genetic model was a major gene model with dominant expression with the risk allele frequency at 15% with 60% penetrance.CONCLUSIONS: In this pilot study the increased inbreeding in the cases, lack of likely sampling bias, the increased frequency of T2D in Burmese, and small number of breed founders are consistent with the involvement of a major locus in diabetes in Burmese cats with a significant risk allele prevalence. However, low case numbers meant this could not be unambiguously confirmed. A genome-wide association study may be useful for investigating the genetic cause of T2D. 相似文献
102.
MJ Voorhorst JC van Brederode CHJ Albers‐Wolthers J de Gier AC Schaefers‐Okkens 《Reproduction in domestic animals》2013,48(5):840-843
Subinvolution of placental sites (SIPS) is the major cause of persistent sanguineous vaginal discharge after parturition in the bitch. Spontaneous remission is common but may take several months, and hence, medical therapy to end the discharge is often requested. In this retrospective study, we evaluated the effect of treatment for SIPS with low oral doses of a progestagen. Nine bitches with SIPS, but otherwise clinically healthy, were found in the computer database of the Department of Clinical Sciences of Companion Animals. Seven of these bitches were treated with low oral doses of a progestagen (megestrol acetate, 0.1 mg/kg body weight (bw) once daily for the 1st week, then 0.05 mg/kg bw once daily for the 2nd week). The other two bitches were untreated. Treatment results were evaluated by a telephone questionnaire. Progestagen treatment was successful in all of the treated dogs; sanguineous vaginal discharge stopped within the treatment period. One of the two untreated dogs remained symptomatic until the next oestrus, approximately 120 days after parturition, and the other remained symptomatic until 6 weeks before the start of the next pro‐oestrus, 270 days after parturition. No side effects of the progestagen treatment were observed. Subsequent gestations, parturitions and puerperal periods of 5 mated bitches were uneventful. One bitch did not become pregnant after mating. In conclusion, the results of this study indicate that oral administration of low doses of progestagen for 2 weeks is effective in stopping persistent sanguineous vaginal discharge in bitches with SIPS, with neither side effects nor reduced subsequent fertility. 相似文献
103.
C. N. Albers G. T. Banta O. S. Jacobsen & P. E. Hansen 《European Journal of Soil Science》2008,59(4):693-705
Humic substances (HS) often are dominant constituents of soil organic matter. In this study 28 fractions of HS were purified and chemically characterized from horizons of three Danish soils differing in texture. A commercial humic acid (HA) was included for comparison. The HS fractions were chemically characterized by CHNS analysis, pH-titration and liquid state 13 C-NMR experiments. Amino acids and carbohydrates could clearly be differentiated from other O- and N-aliphatic compounds. The data were analysed by principal component analysis. The analysis revealed greater difference between HS fractions than between locations. The characteristics of the HS fractions were compared with several models in the literature and an average structural model for one HA and one FA fraction is proposed. 相似文献
104.
家蚕新品种春华×秋实,经省级实验室联合鉴定,春期万蚕产茧量、万蚕茧层量、解舒丝长、解舒率比对照种菁松×皓月高7.6%、3.3%、11.6%、13.7%,净度高2.75分,出丝率略低,其余经济性状相仿.秋期饲养万蚕茧层量、解舒丝长、解舒率、出丝率比对照种秋丰×白玉提高6.9%、6.4%、16.3%、9.7%、4.1%,其他经济性状与对照相仿.两年农村生产鉴定结果,盒种产茧量比对照种高5.3%,产值高4.7%,50 kg桑产值高3.5%,茧丝长、解舒丝长、解舒率、干毛茧出丝率分别比对照种提高8.1%、13.0%、3.8%、2.9%. 相似文献
105.
106.
Henderson KS Dole V Parker NJ Momtsios P Banu L Brouillette R Simon MA Albers TM Pritchett-Corning KR Clifford CB Shek WR 《Veterinary pathology》2012,49(3):440-452
A prevalent and distinctive infectious interstitial pneumonia (IIP) of immunocompetent laboratory rats was suspected to be caused by a putative virus, termed rat respiratory virus, but this was never substantiated. To study this disease, 2 isolators were independently populated with rats from colonies with endemic disease, which was perpetuated by the regular addition of naive rats. After Pneumocystis was demonstrated by histopathology and polymerase chain reaction (PCR) in the lungs of rats from both isolators and an earlier bedding transmission study, the relationship between Pneumocystis and IIP was explored further by analyzing specimens from 3 contact transmission experiments, diagnostic submissions, and barrier room breeding colonies, including 1 with and 49 without IIP. Quantitative (q) PCR and immunofluorescence assay only detected Pneumocystis infection and serum antibodies in rats from experiments or colonies in which IIP was diagnosed by histopathology. In immunocompetent hosts, the Pneumocystis concentration in lungs corresponded to the severity and prevalence of IIP; seroconversion occurred when IIP developed and was followed by the concurrent clearance of Pneumocystis from lungs and resolution of disease. Experimentally infected immunodeficient RNU rats, by contrast, did not seroconvert to Pneumocystis or recover from infection. qPCR found Pneumocystis at significantly higher concentrations and much more often in lungs than in bronchial and nasal washes and failed to detect Pneumocystis in oral swabs. The sequences of a mitochondrial ribosomal large-subunit gene region for Pneumocystis from 11 distinct IIP sources were all identical to that of P. carinii. These data provide substantial evidence that P. carinii causes IIP in immunocompetent rats. 相似文献
107.
克氏原螯虾原肌球蛋白的纯化及过敏原性分析 总被引:1,自引:0,他引:1
以13份甲壳类动物过敏患者血清的Western—blotting分析,确定克氏原螯虾主要过敏原为36ku蛋白质.通过盐析、等电点沉淀及热处理等方法纯化该蛋白质,以兔抗拟穴青蟹原肌球蛋白(Tropo-myosin,TM)多克隆抗体的Western—blotting分析,确定该蛋白质为TM.同源性分析表明,克氏原螯虾TM与南美白对虾TM、拟穴青蟹的氨基酸序列相似性较高(〉90%).酶切位点预测显示,它分别有49个胰蛋白酶和6个胰凝乳蛋白酶的酶切位点.模拟胃肠液消化实验结果显示,纯化TM不易被胃蛋白酶降解,易于被胰蛋白酶和胰凝乳蛋白酶降解,进一步的Western—blotting和抑制性ELISA分析结果显示,其消化产物仍具有一定的免疫活性.采用蒸煮处理可降低TM的消化稳定性及免疫活性,且蒸煮处理时间越长,效果越显著.说明。TM为克氏原螯虾主要过敏原.与其他甲壳娄动物TM的序列相似件较高. 相似文献
108.
CM Lucci LL Schreier GM Machado CA Amorim SN Báo JR Dobrinsky 《Reproduction in domestic animals》2007,42(1):76-82
The purpose of this study was to evaluate the effect of cooling ovarian tissue on pig pre-antral follicles. Ovaries were maintained in saline solution (0.9%) at 4 or 20 degrees C for 6, 12 or 18 h. After storage, pre-antral follicles were morphologically evaluated. While primordial follicles were not affected by the storage, the percentage of morphologically normal growing follicles was significantly reduced in ovarian tissue stored at 20 degrees C for 12 or 18 h. To test the viability of stored follicles, growing follicles isolated from ovaries stored at 4 degrees C for 18 h and at 20 degrees C for 6 h were cultured for 3 days. Follicles stored in either condition presented the same growth pattern in vitro as fresh follicles. We conclude that storage of pig ovaries at 4 degrees C for up to 18 h or at 20 degrees C for up to 6 h does not affect the morphology of growing follicles or their ability to grow in vitro. 相似文献
109.
110.
The DOD carefully evaluates its technical needs and executes programs of sponsored research and development to fulfill them. Thus, while individual projects proceed in accordance with established scientific principles of objectivity, the overall system of DOD funding allows the military to influence the development of science technology. Many have argued that this system of contracts and grants has well served science and the universities. One cannot deny that the influx of money led to rapid progress in selected scientific fields and increased scientific institutions' affluence. With this fact we have no quarrel. However, these same people often continue to argue that the systems of federal funding for science, specifically DOD funding of science, follows merely on the work's scientific merit, not on how it fits any larger scheme. They continue, that, since DOD supports good science for its own sake, the combination of military money and universities strongly encouraging faculty to seek that money encourages healthy competition for faster scientific progress. The DOD's approval process is seen to follow from the scientist up, with the military deciding which proposals for research have the most intrinsic (scientific) merit, then after the fact, thinking up a military justification for congressional budget requests. It is this latter belief with which we take issue. The DOD considers the scientific worth of the proposals for research it receives, but only after it has determined that the proposal fulfills a specific military need. This fact and its implications for the university as an institution charged with protecting the process by which man discovers new knowledge have been ignored in the debates over DOD sponsored research and development in universities. In addition, the Nixon Administration's efforts to tighten management controls over civilian research, especially in the biomedical and energy areas, promises to further undermine the university's role as an institution charged with fostering a search for truth free from bias in both methodology and subject selection. 相似文献