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Skin and tumor grafting experiments performed on F1 hybrid mice indicate that theH(Tla) histocompatibility system is composed of at least two genetic loci,H(Tla-1) andH(Tla-2), and that one of these loci,H(Tla-1), has at least three alleles. We suggest thatH(Tla-1) andH(Tla-2) be renamedH-31 andH-32, respectively. 相似文献
33.
We have used three selective inhibitors of arachidonic acid metabolism in order to investigate the role of lipoxygenase metabolites in the pathogenesis of traumatic shock (LD90). The following inhibitors were used: CGS-5391B (2.5 mg/kg), a cyclooxygenase and lipoxygenase inhibitor, CGS-5677 (2.0 mg/kg), a selective lipoxygenase inhibitor, and U-60, 257 (0.3 mg/kg), a putative inhibitor of glutathione-s-transferase. These inhibitors did not alter arterial blood pressure or heart rate when given to sham shock rats. The traumatic shock model was characterized by a 4.5-fold increase in plasma cathepsin D activity, a 4-fold increase in plasma myocardial depressant factor (MDF) activity, and a mean survival time of 1.5 ± 0.2 h. Only the dual inhibitor significantly blunted the accumulation of cathepsin D in the plasma (7.5 ± 0.8 vs 11.3 ± 0.8 U/ml, p<0.01). However, all three inhibitors significantly suppressed plasma MDF accumulation by 50–60%: CGS-5391B, CGS-5677, and U-60,2257 (p<0.01). Moreover, these three agents significantly improved survival time in traumatic shock. The increased survival time and reduced MDF activity afforded by these inhibitors suggest a significant role for lipoxygenase metabolites, particularly LTC4 and LTD4, in the pathogenesis of traumatic shock. 相似文献
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Chris Degeling Melanie Rock Lorraine Teows 《Journal of applied animal welfare science : JAAWS》2013,16(4):286-303
In industrialized societies, more than 1 in 3 dogs and people currently qualify as overweight or obese. Experts in public health expect both these figures to rise. Although clinical treatment remains important, so are public perceptions and social norms. This article presents a thematic analysis of English-language mass media coverage on canine obesity from 2000 through 2009 and compares these results with a thematic analysis of articles on canine obesity in leading veterinary journals during the same time period. Drawing on Giddens's theory of structuration, this study identified articles that emphasized individual agency, environmental structure, or both as contributors to canine obesity. Comparisons with weight-related health problems in human populations were virtually absent from the veterinary sample. Although such comparisons were almost always present in the media sample, quotations from veterinarians and other spokespeople for the welfare of nonhuman animals emphasized the agency of individual caregivers (owners) over structural influences. Now that weight gain and obesity have been established as a pressing animal welfare problem, these results suggest a need for research and for interventions, such as media advocacy, that emphasize intersections between animal-owner agency, socioenvironmental determinants, and connections between animal welfare and human health. 相似文献
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Sreenath R. Palle LeAnne M. Campbell Devendra Pandeya Lorraine Puckhaber Lauren K. Tollack Sylvain Marcel Sabarinath Sundaram Robert D. Stipanovic Thomas C. Wedegaertner Lori Hinze Keerti S. Rathore 《Plant biotechnology journal》2013,11(3):296-304
Cottonseed remains a low‐value by‐product of lint production mainly due to the presence of toxic gossypol that makes it unfit for monogastrics. Ultra‐low gossypol cottonseed (ULGCS) lines were developed using RNAi knockdown of δ‐cadinene synthase gene(s) in Gossypium hirsutum. The purpose of the current study was to assess the stability and specificity of the ULGCS trait and evaluate the agronomic performance of the transgenic lines. Trials conducted over a period of 3 years show that the ULGCS trait was stable under field conditions and the foliage/floral organs of transgenic lines contained wild‐type levels of gossypol and related terpenoids. Although it was a relatively small‐scale study, we did not observe any negative effects on either the yield or quality of the fibre and seed in the transgenic lines compared with the nontransgenic parental plants. Compositional analysis was performed on the seeds obtained from plants grown in the field during 2009. As expected, the major difference between the ULGCS and wild‐type cottonseeds was in terms of their gossypol levels. With the exception of oil content, the composition of ULGCS was similar to that of nontransgenic cottonseeds. Interestingly, the ULGCS had significantly higher (4%–8%) oil content compared with the seeds from the nontransgenic parent. Field trial results confirmed the stability and specificity of the ULGCS trait suggesting that this RNAi‐based product has the potential to be commercially viable. Thus, it may be possible to enhance and expand the nutritional utility of the annual cottonseed output to fulfil the ever‐increasing needs of humanity. 相似文献
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Kai Yuan Jaymelynn K. Farney Laman K. Mamedova Lorraine M. Sordillo Barry J. Bradford 《PloS one》2013,8(11)
Inflammation may be a major contributing factor to peripartum metabolic disorders in dairy cattle. We tested whether administering an inflammatory cytokine, recombinant bovine tumor necrosis factor-α (rbTNFα), affects milk production, metabolism, and health during this period. Thirty-three Holstein cows (9 primiparous and 24 multiparous) were randomly assigned to 1 of 3 treatments at parturition. Treatments were 0 (Control), 1.5, or 3.0 µg/kg body weight rbTNFα, which were administered once daily by subcutaneous injection for the first 7 days of lactation. Statistical contrasts were used to evaluate the treatment and dose effects of rbTNFα administration. Plasma TNFα concentrations at 16 h post-administration tended to be increased (P<0.10) by rbTNFα administration, but no dose effect (P>0.10) was detected; rbTNFα treatments increased (P<0.01) concentrations of plasma haptoglobin. Most plasma eicosanoids were not affected (P>0.10) by rbTNFα administration, but 6 out of 16 measured eicosanoids changed (P<0.05) over the first week of lactation, reflecting elevated inflammatory mediators in the days immediately following parturition. Dry matter and water intake, milk yield, and milk fat and protein yields were all decreased (P<0.05) by rbTNFα treatments by 15 to 18%. Concentrations of plasma glucose, insulin, β-hydroxybutyrate, non-esterified fatty acids, triglyceride, 3-methylhistidine, and liver triglyceride were unaffected (P>0.10) by rbTNFα treatment. Glucose turnover rate was unaffected (P = 0.18) by rbTNFα administration. The higher dose of rbTNFα tended to increase the risk of cows developing one or more health disorders (P = 0.08). Taken together, these results indicate that administration of rbTNFα daily for the first 7 days of lactation altered inflammatory responses, impaired milk production and health, but did not significantly affect liver triglyceride accumulation or nutrient metabolism in dairy cows. 相似文献
39.
Andrew Speakman Alison Rodger Andrew N. Phillips Richard Gilson Margaret Johnson Martin Fisher Ed Wilkins Jane Anderson Rebecca O’Connell Monica Lascar Kazeem Aderogba Simon Edwards Jeffrey McDonnell Nicky Perry Lorraine Sherr Simon Collins Graham Hart Anne M. Johnson Alec Miners Jonathan Elford Anna-Maria Geretti William J. Burman Fiona C. Lampe 《PloS one》2013,8(10)
Life expectancy for people diagnosed with HIV has improved dramatically however the number of new infections in the UK remains high. Understanding patterns of sexual behaviour among people living with diagnosed HIV, and the factors associated with having condom-less sex, is important for informing HIV prevention strategies and clinical care. In addition, in view of the current interest in a policy of early antiretroviral treatment (ART) for all people diagnosed with HIV in the UK, it is of particular importance to assess whether ART use is associated with increased levels of condom-less sex. In this context the ASTRA study was designed to investigate current sexual activity, and attitudes to HIV transmission risk, in a large unselected sample of HIV-infected patients under care in the UK. The study also gathered background information on demographic, socio-economic, lifestyle and disease-related characteristics, and physical and psychological symptoms, in order to identify other key factors impacting on HIV patients and the behaviours which underpin transmission. In this paper we describe the study rationale, design, methods, response rate and the demographic characteristics of the participants. People diagnosed with HIV infection attending 8 UK HIV out-patient clinics in 2011-2012 were invited to participate in the study. Those who agreed to participate completed a confidential, self-administered pen-and-paper questionnaire, and their latest CD4 count and viral load test results were recorded. During the study period, 5112 eligible patients were invited to take part in the study and 3258 completed questionnaires were obtained, representing a response rate of 64% of eligible patients. The study includes 2248 men who have sex with men (MSM), 373 heterosexual men and 637 women. Future results from ASTRA will be a key resource for understanding HIV transmission within the UK, targeting prevention efforts, and informing clinical care of individuals living with HIV. 相似文献
40.
Denice S. Feig Baiju R. Shah Lorraine L. Lipscombe C. Fangyun Wu Joel G. Ray Julia Lowe Jeremiah Hwee Gillian L. Booth 《PLoS medicine》2013,10(4)