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41.
QTL analysis of Cercospora leaf spot resistance in sugar beet   总被引:3,自引:0,他引:3  
The inheritance of Cercospora leaf spot resistance in sugar beet was investigated by means of quantitative trait loci (QTL) analysis of a segregating population of 193 individuals, using 110 AFLP and 35 restriction fragment length polymorphism (RFLP) markers. Five QTL were found through composite interval mapping on linkage groups 1, 2, 3, and 9, respectively, two of which were linked on linkage group 3. The significance of these QTL was tested by permutation analysis The QTL had mostly additive, but also certain negative dominance effects; all the resistance alleles came from the Cercospora-resistant parent. Each quantitative trait locus accounted for 7-18% of the phenotypic variation, leaving 37% of the variation unexplained. The results are discussed in relation to the potential use of marker-assisted breeding for Cercospora leaf spot resistance in sugar beet.  相似文献   
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43.
Underlying principle for fluid therapy is the knowledge about distribution of body water (60% of body weight) into compartments: intra- and extracellular fluid (ICF, ECF) cover respectively one half, one sixth of the latter fills the intravascular system. According to the concentration of ions and molecules in the lost fluids, dehydration is classified into hypertone, hypotone and isotone. Clinical assessment and laboratory examination (PCV, hemoglobin, total protein, urine analysis, electrolyte and blood gas evaluation) are crucial features for determination of dehydration rate, acid-base and electrolyte imbalances. Derangements of body-fluid and electrolyte metabolism and their treatment are discussed. The quantity of fluids necessary for rehydration of the patient is calculated on the basis of clinical findings. Overhydration risk has to be considered more seriously in cats than dogs. Intravenous, subcutaneous, oral and intraperitoneal infusions are feasible. A survey to technical aspects and required instruments is presented in conclusion.  相似文献   
44.
Urine calculi should always been analyzed for constituents. In this paper a commercially available test kit is described for determination of carbonate, calcium, oxalate, ammonium, phosphate, magnesium, urate and cystine. The method is simply to be performed and can be recommended for practitioners.  相似文献   
45.
This abstract gives a survey of the currently used methods in clinical chemistry for the diagnosis of diseases in dog and cat. The laboratory diagnostic methods are presented with emphasis on diseases of liver, kidney, exocrine and endocrine pancreas, thyroid, adrenal gland, muscles, bones and joints and the water and electrolyte metabolism.  相似文献   
46.
T-cell subsets were studied by flow cytometry in 58 feline leukaemia virus (FeLV)-positive cats with naturally acquired FeLV infection to determine whether the changes in CD4+ or CD8+ T cell populations differed from those observed in 55 feline immunodeficiency virus (FIV)-positive cats with naturally acquired FIV infection. The sole criterion for inclusion into the study was seropositivity. Mean (SD) CD4+ T cell values of FeLV positive cats were decreased to 31·1 (8·0) per cent and their CD8+ T cell values were increased to 22·8 (6·3) per cent in comparison with uninfected control cats (37·9 [9·5] per cent CD4+; 15·2 [6·3] per cent CD8+). The CD4+/CD8+ ratio was reduced to 1·5 (0·7), compared with 3·0 (1·5) in 39 FeLv- and FIV-negative control cats. Differences from control values were significant, but there was no significant difference between CD4+ and CD8+ lymphocytes of FeLV- versus FIV-infected cats. These findings indicate that FeLv and FIV have similar effects on T lymphocyte subsets. Both retrovirus infections can induce immunodeficiency, both viruses infect a broad range of lymphohaemopoietic cells, despite having different primary target cells, and can induce the killing of lymphocytic cells in vitro. It is concluded that a decreased CD4+/CD8+ ratio is not restricted to FIV infections but may also occur in FeLv infection.  相似文献   
47.
Plasma concentrations of endothelin (ET)-1 and -3 were determined simultaneously in dogs with various pathophysiological conditions, because these peptides may display different pharmacological profiles. The study pays special attention to the characterization of plasma ET immunoreactivity (ET-IR), using high-pressure liquid chromatography (HPLC) analysis with off-line detection by radioimmunoassay (RIA). In most sick dogs evaluated total plasma ET-1-IR concentration did not differ from that of healthy dogs. However, HPLC analysis of their total plasma ET-1 -IR revealed distinct ET-IR profiles. Big-ET-1, which is barely detectable in control dogs, does represent the predominant ET in sick dogs. Regardless of the pathophysiological conditions, considerable amounts of high-molecular weight ET-1-IR, most likely aggregated ET-material, was found consistently. With respect to ET-3, we constantly observed moderately increased concentrations, though no major difference of molecular pattern was evident between healthy and sick dogs. The data show a distinct regulation of ET-1 and ET-3 in dogs. Furthermore, specific molecular forms of ET-IR were found to occur in various diseases. The endothelins may therefore prove to be of diagnostic importance in the pathophysiology of vascular diseases.  相似文献   
48.
Sensitivity and specificity were determined for the cytologic detection of malignant tumors in canine and feline body cavity effusions. In a prospective study, 424 body cavity effusions from dogs and cats were collected and evaluated, including 70 pleural and 163 peritoneal effusions from dogs, and 77 pleural and 114 peritoneal effusions from cats. Final diagnoses were confirmed in 339 of the 424 cases by clinical follow-up, necropsy, and in the case of malignant tumors, Histopathology. Malignant tumors were found in 18% of canine and 25% of feline body cavity effusions. Approximately one-half of tumors in both dogs and cats were carcinomas. Discrete cell tumors accounted for 56% of feline neoplastic effusions. The sensitivity of cytologic evaluation for the detection of malignant tumors in body cavity effusions was 64% for dogs and 61% for cats. Specificity was 99% for canine and 100% for feline effusions. Sensitivity and specificity were comparable to those obtained with cytologic evaluation of human samples.  相似文献   
49.
A three-year-old male Boxer dog had hyperesthesia, symmetrical epaxial, gluteal and hind limb muscular atrophy and rear limb ataxia. Neurological deficits included decreased conscious proprioception of the left hind limb, decreased withdrawal and increased patellar reflexes of both hind limbs. The dog had a urinary tract infection with positive culture for Staphylococcus intermedius. On survey radiography of the lumbosacral spine there was active bone proliferation spanning the L7 S1 intervertebral disc space with an epidural filling defect at the ventral aspect of the vertebral canal on epidurography, On magnetic resonance imaging (MRI), findings were similar to those described for human diskospondylitis including altered signal intensity and nonuniform contrast enhancement of the L7-S1 intervertebral disc, adjacent vertebral end plates and epidural and sublumbar soft tissues. Although skeletal radiography is usually sufficient to reach a diagnosis of discospondylitis, MRI of this patient made it possible to reach a presumptive diagnosia of discospondyltis prior to development of definitive radiographic abnormalties.  相似文献   
50.
为实现植物生命需水状况的无损检测,通过定量辨识植物叶态萎蔫特征反映植物亏水胁迫状况,基于分形理论"双毯法"定义了萎蔫指数LDBM,利用基于激光三角原理的三维激光扫描仪获取植物叶片表型点云数据,以西葫芦、秋葵、葫芦、南瓜4种植物为研究对象,结合饱和水汽压差与光合有效辐射2种微环境参数,进行了植物叶态萎蔫定量辨识研究。试验分析了4种植物萎蔫指数LDBM的日变化曲线,证明LDBM用于表征叶态萎蔫状况是合理和可行的;分析了萎蔫指数LDBM与微环境参数的相关性,4种植物LDBM与饱和水汽压差相关系数均大于0.81,与光合有效辐射相关系数均大于0.71,与2种参数都有很强的正相关性;并且与基于离散时域傅里叶变换定义的萎蔫指数L2DFT进行了对比,LDBM与L2DFT呈负相关性,4种植物的相关系数均大于0.82,表明LDBM能够准确地定量表征叶态萎蔫。  相似文献   
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