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61.
Barger A Graca R Bailey K Messick J de Lorimier LP Fan T Hoffmann W 《Veterinary pathology》2005,42(2):161-165
Aspiration of lytic bone lesions is an excellent diagnostic test in the initial evaluation of primary bone neoplasia. However, cytologically, it can be difficult to differentiate osteosarcoma (OSA) from other bone neoplasms, including fibrosarcoma, chondrosarcoma, synovial cell sarcoma, and plasma cell myeloma. The purpose of this study is to determine the sensitivity and specificity of alkaline phosphatase (ALP) staining to differentiate OSA from other tumors that express vimentin by immunocytochemistry or immunohistochemistry. ALP is a hydrolytic enzyme present in multiple tissues including liver, kidney, intestine, placenta, and bone. Hypothetically, neoplasms actively producing bone should be specifically positive for ALP staining. Unstained, cytologic specimens were incubated for 8-10 minutes with nitroblue tetrazolium chloride/5-bromo-4-chloro-3-indolyl phosphate toluidine salt-phosphatase substrate. A positive reaction stains the membrane of the cells gray to black. Samples were counterstained with a Romanowsky's stain to determine whether the sample was of representative cellularity. A total of 61 vimentin-positive neoplasms have been evaluated and confirmed histopathologically. Tumors that expressed vimentin and were positive for ALP included 33 OSAs, one multi-lobular tumor of bone, one amelanotic melanoma, and one chondrosarcoma. Tumors that expressed vimentin and were negative for ALP included chondrosarcomas (three of four), multiple fibrosarcomas, and multiple synovial cell sarcomas. The sensitivity is 100%, and the specificity is 89%. In conclusion, ALP appears to be a highly sensitive and fairly specific marker in the diagnosis of OSA. 相似文献
62.
Sandra A. Loftus BA Jill M. Montplaisir BS Jing-wen Kuo MS Dale P. DeVore PhD 《Journal of Equine Veterinary Science》1988,8(2)
A standardized investigation was conducted to compare the biophysical properties of hyaluronate products used in the treatment of joint dysfunction in horses. Results showed that two of the five products, Hyvisc® and Hylartin®V, contained higher-weight molecular hyaluronate (greater than 1.5×106). Other investigations have shown that higher molecular weight hyaluronate is effective in providing physical resistance to shear, in stimulating endogenous hyaluronate synthesis, and in inhibiting excess cell proliferation which may be associated with synovial pannus formation. It is suggested that the therapeutic benefits of hyaluronate products may be dependent on the molecular size of the hyaluronate molecules. Higher molecular weight hyaluronate products would be expected to be more effective than lower molecular hyaluronate products in providing therapeutic benefits. 相似文献
63.
Grünberg W Morin DE Drackley JK Barger AM Constable PD 《Journal of the American Veterinary Medical Association》2006,229(3):413-420
OBJECTIVE: To determine the effect of continuous IV administration of 50% dextrose solution on phosphorus homeostasis in lactating dairy cows. DESIGN: Clinical trial. ANIMALS: 4 multiparous Jersey cows. PROCEDURES: Cows were administered 50% dextrose solution IV (0.3 g/kg/h [0.14 g/lb/h]) for 5 days. Plasma concentrations of glucose, immune-reactive insulin (IRI), and phosphorus were determined before, during, and for 72 hours after dextrose infusion. Phosphorus intake and losses of phosphorus in urine, feces, and milk were determined. Each cow received a sham treatment that included instrumentation and sampling but not administration of dextrose. RESULTS: Plasma glucose, IRI, and phosphorus concentrations were stable during sham treatment. Plasma phosphorus concentration decreased rapidly after onset of dextrose infusion, reaching a nadir in 24 hours and remaining less than baseline value for 36 hours. Plasma phosphorus concentration increased after dextrose infusion was stopped, peaking in 6 hours. Urinary phosphorus excretion did not change during dextrose infusion, but phosphorus intake decreased because of reduced feed intake, followed by decreased fecal phosphorus loss and milk yield. Rapid changes in plasma phosphorus concentration at the start and end of dextrose infusion were temporally associated with changes in plasma glucose and IRI concentrations and most likely caused by compartmental shifts of phosphorus. CONCLUSIONS AND CLINICAL RELEVANCE: Hypophosphatemia developed in response to hyperglycemia or hyperinsulinemia in dairy cows administered dextrose via continuous IV infusion. Veterinarians should monitor plasma phosphorus concentration when administering dextrose in this manner, particularly in cows with decreased appetite or preexisting hypophosphatemia. 相似文献
64.
【目的】建立羊踯躅嫩叶离体培养及植株高效再生体系。【方法】以羊踯躅新生嫩叶为外植体,筛选嫩叶愈伤组织诱导、再分化及生根培养基,并以再生植株茎节为试材,建立高效植株再生体系。【结果】最适合羊踯躅嫩叶愈伤组织诱导的培养基为1/2 DR+2.40 mg/L 2ip+0.80 mg/L NAA,诱导率为99.5%;愈伤组织再分化的最佳培养基为1/2 DR+2.90 mg/L 2ip+0.01 mg/L NAA+1.75 mg/L KT,分化率为99.7%;适宜生根的培养基为1/4 DR+0.06 mg/L ZT+0.02 mg/L NAA,生根率达99.0%。利用再生植株茎节的快繁结果表明,在28 d的培养周期内,每节段平均增殖达5倍以上。【结论】成功建立了羊踯躅嫩叶愈伤组织诱导、再分化芽苗和植株高效再生体系,可以满足羊踯躅工厂化育苗的需要。 相似文献
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采用荷斯坦奶牛X性控冻精和超数排卵技术结合生产奶牛性控胚胎,以建立高效、低成本的体内性控胚胎生产方法。研究发现,使用CIDR和Cue-Mate进行奶牛同期发情处理,发情率分别为90.9%和100%(P<0.05),且Cue-Mate的发情时间更加集中;加拿大的FOLLTROPIN-V和中国科学院动物研究所的FSH对奶牛超排效果影响不显著,分别为头均胚胎数10.08枚±8.08枚、头均可用胚胎数2.38枚±3.07枚和头均胚胎数6.57枚±4.31枚、头均可用胚胎数2.00枚±1.88枚,无显著差异(P>0.05);奶牛发情后12h~14h和16h~19h人工授精,分别获得头均胚胎数10.25枚±5.53枚、头均可用胚胎数5.33枚±4.52枚和头均胚胎数10.13枚±6.93枚、头均可用胚胎数5.88枚±6.26枚,无显著差异(P>0.05)。但是未受精胚胎数差异显著(27对7,P<0.05)。 相似文献
70.