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861.
One of the most frequently given reasons for relinquishing a companion animal to an animal shelter is that the person or family is moving. Telephone interviews conducted with 57 caregivers who relinquished animal companions to a shelter in the midwestern United States covered details of the move, characteristics both of the caregivers and the animals, and efforts to avoid relinquishment. A human-nonhuman animal bonding scale also was administered. Although some participants had additional reasons for relinquishment, the majority had given up their pets solely because they were moving. Most had relatively low income, were moving for employment reasons, and were renting their homes. Landlord restrictions were an important factor in relinquishment. High scores on the bonding scale and spontaneous expressions of discomfort and sorrow suggest that external pressures overrode attachment to the animal and the pain of relinquishment. 相似文献
862.
863.
Enhanced fungal resistance in transgenic cotton expressing an endochitinase gene from Trichoderma virens 总被引:2,自引:0,他引:2
Emani C Garcia JM Lopata-Finch E Pozo MJ Uribe P Kim DJ Sunilkumar G Cook DR Kenerley CM Rathore KS 《Plant biotechnology journal》2003,1(5):321-336
Mycoparasitic fungi are proving to be rich sources of antifungal genes that can be utilized to genetically engineer important crops for resistance against fungal pathogens. We have transformed cotton and tobacco plants with a cDNA clone encoding a 42 kDa endochitinase from the mycoparasitic fungus, Trichoderma virens. Plants from 82 independently transformed callus lines of cotton were regenerated and analysed for transgene expression. Several primary transformants were identified with endochitinase activities that were significantly higher than the control values. Transgene integration and expression was confirmed by Southern and Northern blot analyses, respectively. The transgenic endochitinase activities were examined in the leaves of transgenic tobacco as well as in the leaves, roots, hypocotyls and seeds of transgenic cotton. Transgenic plants with elevated endochitinase activities also showed the expected 42 kDa endochitinase band in fluorescence, gel-based assays performed with the leaf extracts in both species. Homozygous T2 plants of the high endochitinase-expressing cotton lines were tested for disease resistance against a soil-borne pathogen, Rhizoctonia solani and a foliar pathogen, Alternaria alternata. Transgenic cotton plants showed significant resistance to both pathogens. 相似文献
864.
865.
Frederique Ponchel Carmel Toomes Kieran Bransfield Fong T Leong Susan H Douglas Sarah L Field Sandra M Bell Valerie Combaret Alain Puisieux Alan J Mighell Philip A Robinson Chris F Inglehearn John D Isaacs Alex F Markham 《BMC biotechnology》2003,3(1):1-13
Background
Real-time PCR is increasingly being adopted for RNA quantification and genetic analysis. At present the most popular real-time PCR assay is based on the hybridisation of a dual-labelled probe to the PCR product, and the development of a signal by loss of fluorescence quenching as PCR degrades the probe. Though this so-called 'TaqMan' approach has proved easy to optimise in practice, the dual-labelled probes are relatively expensive.Results
We have designed a new assay based on SYBR-Green I binding that is quick, reliable, easily optimised and compares well with the published assay. Here we demonstrate its general applicability by measuring copy number in three different genetic contexts; the quantification of a gene rearrangement (T-cell receptor excision circles (TREC) in peripheral blood mononuclear cells); the detection and quantification of GLI, MYC-C and MYC-N gene amplification in cell lines and cancer biopsies; and detection of deletions in the OPA1 gene in dominant optic atrophy.Conclusion
Our assay has important clinical applications, providing accurate diagnostic results in less time, from less biopsy material and at less cost than assays currently employed such as FISH or Southern blotting. 相似文献866.
Activation of 2'-O-substituted ribonucleoside phosphoramidites with various activators during solid-supported synthesis of phosphorothioate oligonucleotides was studied. The Rp:Sp diastereomeric composition of resulting phosphorothioate linkage dependent on pKa of activator utilized for coupling. 相似文献
867.
868.
Lee SH Dimock K Gray DA Beauchemin N Holmes KV Belouchi M Realson J Vidal SM 《Trends in genetics : TIG》2003,19(8):447-457
Genetic studies of host susceptibility to infection contribute to our understanding of an organism's response to pathogens at the immunological, cellular, and molecular levels. In this review we describe how the study of host genetics in mouse models has helped our understanding of host defense mechanisms against viral infection, and how this knowledge can be extended to human infections. We focus especially on the innate mechanisms that function as the host's first line of defense against infection. We also discuss the main issues that confront this field, as well as its future. 相似文献
869.
Price TB Krishnan-Sarin S Rothman DL 《American journal of physiology. Endocrinology and metabolism》2003,285(1):E116-E122
Cigarette smoking is a leading cause of many adverse health consequences. Chronic nicotine exposure leads to insulin resistance and may increase the risk of developing non-insulin-dependent diabetes mellitus in young otherwise healthy smokers. To evaluate smoking-induced effects on carbohydrate metabolism, we studied muscle glycogen recovery from exercise in a young healthy population of smokers. The study used 31P-13C NMR spectroscopy to compare muscle glycogen and glucose 6-phosphate levels during recovery in exercised gastrocnemius muscles of randomized cohorts of healthy male smokers (S) and controls (C). Data for the two groups were as follows: S, > or =20 cigarettes/day (n = 8), 24 +/- 2 yr, 173 +/- 3 cm, 70 +/- 4 kg and age- and weight-matched nonsmoking C (n = 10), 23 +/- 1 yr, 175 +/- 3 cm, 67 +/- 3 kg. Subjects performed single-leg toe raises to deplete glycogen to approximately 20 mmol/l, and glycogen resynthesis was measured during the first 4 h of recovery. Plasma samples were assayed for glucose and insulin at rest and during recovery. Test subjects were recruited from the general community surrounding Yale University. Glycogen was depleted to similar levels in the two groups [23.5 +/- 1.2 (S) and 19.1 +/- 1.3 (C) mmol/l]. During the 1st h of recovery, glycogen synthesis rates were similar [13.8 +/- 1.1 (S) and 15.3 +/- 1.3 (C) mmol x l-1 x h-1]. Between hours 1 and 4, glycogen synthesis was impaired in smokers [0.8 +/- 0.2 (S) and 4.5 +/- 0.5 (C) mmol x l-1 x h-1, P = 0.0002] compared with controls. Glucose 6-phosphate was reduced in smokers during hours 1-4 [0.105 +/- 0.006 (S) and 0.217 +/- 0.019 (C) mmol/l, P = 0.0212]. We conclude that cigarette smoking impairs the insulin-dependent portion of muscle recovery from glycogen-depleting exercise. This impairment likely results from a reduction in glucose uptake. 相似文献
870.
Hodgson DM Zingman LV Kane GC Perez-Terzic C Bienengraeber M Ozcan C Gumina RJ Pucar D O'Coclain F Mann DL Alekseev AE Terzic A 《The EMBO journal》2003,22(8):1732-1742
ATP-sensitive potassium (K(ATP)) channels are required for maintenance of homeostasis during the metabolically demanding adaptive response to stress. However, in disease, the effect of cellular remodeling on K(ATP) channel behavior and associated tolerance to metabolic insult is unknown. Here, transgenic expression of tumor necrosis factor alpha induced heart failure with typical cardiac structural and energetic alterations. In this paradigm of disease remodeling, K(ATP) channels responded aberrantly to metabolic signals despite intact intrinsic channel properties, implicating defects proximal to the channel. Indeed, cardiomyocytes from failing hearts exhibited mitochondrial and creatine kinase deficits, and thus a reduced potential for metabolic signal generation and transmission. Consequently, K(ATP) channels failed to properly translate cellular distress under metabolic challenge into a protective membrane response. Failing hearts were excessively vulnerable to metabolic insult, demonstrating cardiomyocyte calcium loading and myofibrillar contraction banding, with tolerance improved by K(ATP) channel openers. Thus, disease-induced K(ATP) channel metabolic dysregulation is a contributor to the pathobiology of heart failure, illustrating a mechanism for acquired channelopathy. 相似文献