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1.
应激性急性肾上腺皮质功能不全症的病理机制十分复杂,目前人医的各类文献中大都以“垂体—肾上腺轴”功能不全、功能衰竭、或发生广泛性出血坏死性病演作解释。本病在奶牛分娩难产过程中并不少见,病牛的症状表现以心衰和失钠性低血症为主征。但在兽医临床上由于认识不足,曾有不少中外学者将奶牛产后卧地不起的各类疾病,含糊地统称为“母牛睡倒爬不起来综合征”;更由于救治不当,病牛常以淘汰或死亡告终。本文通过对一具体典型病例辨析,着重讨论了本病的基本病理反应和确立诊断依据,强调对本病救护施治时应遵循的基本原则,供同道们在分析和解决这一实际问题时参考。  相似文献   
2.
Dry bean producers in Ontario, Canada, have few herbicide options available for annual broad-leaved weed management and there is little information on the tolerance of dry bean to linuron. The tolerance of black, cranberry, kidney, and white bean to the pre-emergence (PRE) application of linuron at the rates of 0, 500, 1000, 1500, 2000, and 2500 g ai ha−1 was evaluated in field studies conducted in 2005 and 2006 at Exeter and in 2006 at Ridgetown, Ontario. The four market classes differed in their response to linuron. Cranberry and kidney bean were more tolerant to the PRE application of linuron than black and white bean. Linuron applied PRE caused as much as 12% injury in cranberry and kidney bean, 47% injury in black bean, and 56% injury in white bean. Linuron applied PRE at 500–2500 g ai ha−1 had no effect on the height of cranberry and kidney bean but decreased the height by 7, 8, and 15% in black bean and by 10, 13, and 23% in white bean at 1500, 2000, and 2500 g ai ha−1, respectively. Linuron applied PRE at the rates evaluated did not cause any adverse affect on the yield of cranberry, kidney, and white bean but black bean yield was reduced by 16% at 2500 g ai ha−1. Based on these results, there is not an adequate margin of crop safety for the PRE application of linuron in black and white bean at rates >1000 g ai ha−1. However, there is a potential for the use of linuron PRE for weed management in cranberry and kidney bean at the rates evaluated.  相似文献   
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Research on the disease called shimao zheng, which had resulted in widespread fleece-eating and shedding by sheep and goats in the Haizi area of Akesa County of Gansu Province of China, was carried out by both laboratory studies and pathological observations. There was a marked deficiency of sulfur in the wool and tissues of the affected animals. The pathological changes were mainly loss of fleece, exposure of the skin, keratinization of the epidermal cells, narrowing and reduced numbers of the fleece follicles, and fewer sebaceous glands and sweat glands. Histologically, there was atrophy of the striated and cardiac muscles and of the epithelium of the convoluted tubules of the kidney, together with a glomerulonephritis. The disease was considered to be a local nutritional and metabolic disorder, probably mainly caused by sulfur deficiency.  相似文献   
5.
In teleosts, as in other vertebrates, the secretion of pituitary gonadotropin (GTH) is mediated by the hypothalamic decapeptide, gonadotropin-releasing hormone (GnRH). Recent findings in teleosts indicate that GnRH receptors are not restricted to the pituitary gonadotropes and are also associated with somatotropes as well as being present in a number of other tissues. In the present study, we provide novel information on GnRH binding in a number of extrapituitary tissues in goldfish. However, we do not intend to provide full characterization of GnRH binding sites in various extrapituitary tissues in goldfish as this would clearly be outside the scope of this paper. In this study we examined GnRH binding in a number of extrapituitary tissues in goldfish and observed specific binding in ovary, testis, brain, liver and kidney. No specific GnRH binding was observed in muscle, skin, gut, gill and heart. In general, the present findings together with the results of other studies carried out in our laboratory demonstrate that mature goldfish ovary and testis contain two classes of GnRH binding sites, high affinity/low capacity and low affinity/high capacity sites with binding characteristics similar to those of the pituitary GnRH receptors. The brain of goldfish was also found to contain two classes of GnRH binding sites, a super-high affinity/low capacity and a low affinity/high capacity sites. Furthermore, study of goldfish liver and kidney demonstrated the presence of a single class of GnRH binding sites with characteristics different from those of pituitary, ovary, testis and brain. Overall, it is evident that goldfish contains a family of GnRH binding sites which can be classified into four groups based on binding affinities: 1) A class of high affinity binding sites present in the pituitary, ovary and testis, 2) a class of super high affinity sites so far only detected in the brain, 3) a class of intermediate-affinity GnRH binding sites in the liver and kidney, and 4) a class of low affinity binding sites present in all the tissues containing specific GnRH binding sites except for liver and kidney.  相似文献   
6.
Background: It has been speculated that renal disease can be identified through the detection and quantification of microalbuminuria, however, reliable measurement of albuminuria in any quantity can be challenging. Recently, a new point‐of‐care immunoassay was validated for the specific detection of microalbuminuria and early renal disease in dogs. Objectives: The goal of this study was to determine if measurement of microalbuminuria by the point‐of‐care immunoassay correlated with results from routine semiquantitative methods for detecting proteinuria in dogs. Methods: One hundred and thirty‐eight urine samples, from 133 different dogs, submitted for urinalysis to the Clinical Pathology Laboratory at the University of Missouri‐Columbia Veterinary Medical Teaching Hospital were eligible for the study. Samples that contained >20 RBC/high power field (hpf) or >20 WBC/hpf were excluded, as were samples with insufficient volume to complete all tests. All samples were evaluated with a urinary dipstick with or without a sulfosalicylic acid turbidimetric test, a urine protein:creatinine (UPC) ratio, and the immunoassay for microalbuminuria. Data were analyzed by the Spearman rank order correlation. Results: Microalbuminuria results correlated significantly with those of the dipstick (r= 0.715), sulfosalicylic acid test (r= 0.742), and UPC ratio (r= 0.830). Correlation between the immunoassay and UPC ratio was the same (r= 0.830) when only samples with trace or 1+ proteinuria by dipstick were analyzed (n = 51). Conclusions: The point‐of‐care immunoassay results for microalbuminuria correlated with the results of semiquantitative methods for detecting total proteinuria in dogs. Routine methods for canine proteinuria appear to be adequate for determining whether further testing for renal disease is warranted.  相似文献   
7.
为研究脂滴包被蛋白(Perilipin)在猪脂肪组织中的表达分布情况及其与糖皮质激素作用的关系,选取氟烷基因隐性纯合子猪(Halnn)和氟烷基因显性纯合子猪(HalNN)为动物模型,采用半定量实时荧光PCR(rqRT-PCR)技术分析其背脂和肾周脂中perilipin基因及脂肪代谢和糖皮质激素作用相关基因的表达。结果显示:两种氟烷基因型猪的体重、背膘厚和背膘指数无显著差异,但Halnn肾周脂重(P=0.09)和肾周脂指数(P=0.10)有低于HalNN猪的趋势。双因子方差分析结果表明Halnn猪脂肪组织中perilipin mRNA水平显著高于HalNN猪(P<0.05),而糖皮质激素受体基因(GR)表达水平显著低于HalNN猪(P<0.05),11β-羟基类固醇脱氢酶1基因(11β-HSD1)、脂肪酸合成酶基因(FAS)和激素敏感酯酶基因(HSL)表达水平在两种基因型之间无显著差异。背脂中perilipin和GR的表达水平与肾周脂中的无显著差异,背脂中11β-HSD1和FAS表达水平显著高于肾周脂(P<0.05),而HSL在背脂中的表达情况正好相反(P<0.05)。以上结果提示:HalNN与Halnn猪脂肪...  相似文献   
8.
抗真菌转基因大豆对大豆疫霉根腐病抗病性鉴定   总被引:2,自引:0,他引:2  
采用下胚轴伤口接种法,对Southern杂交阳性的转菜豆几丁质酶基因和大麦核糖体失活蛋白基因的双价转基因大豆T2代的5个株系,进行了大豆疫霉根腐病抗病性检测,并通过比较接种后转基因大豆与对照组的死亡率来探讨两者的抗病性差异。结果表明,有4个转基因株系对大豆疫霉根腐病的抗性与非转基因对照组相比有明显提高,另外1个株系与对照组相比没有明显差异。  相似文献   
9.
对二斑叶螨与朱砂叶螨在以四季豆为寄主时的种间竞争进行了研究。结果表明:无论单种种群还是混合种群。二斑叶螨的活动虫态和成虫的内禀增长力均高于朱砂叶螨,这表明在以四季豆为寄主植物时,二斑叶螨比朱砂叶螨具有更强的种问竞争力。  相似文献   
10.
Three-spined stickleback Gasterosteus aculeatus, males were implanted with Silastic capsules filled with different aromatase inhibitors; 1,4,6-androstatriene-3,17-dione or the non-steroidal CGS16949 A, 4-(5,6,7,8-tetrahydrimidazol [1,5-a]pyridin-5-yl) benzonitrile monohydrochloride or empty capsules. The fish were then exposed to long or short photoperiod. Under the long photoperiod most fish in all treatments displayed a hypertrophied kidney (a secondary sexual character in sticklebacks) and completed, quiescent spermatogenesis, similar as in the natural spawning period. Under the short photoperiod the controls had unstimulated kidneys and an active spermatogenesis, whereas the males implanted with both aromatase inhibitors had stimulated kidneys, though not to the extent as in the long photoperiod, and completed, quiescent spermatogenesis. These findings suggest that aromatization is of importance for the inhibitory effects of short photoperiod on reproduction in the stickleback. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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