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犬乳腺肿瘤在兽医临床中非常常见,母犬乳腺瘤发病率约占全部肿瘤性疾病的25%～42%[1] .其早期治疗主要依靠外科切除的方法,但对已经转移的犬乳腺肿瘤,通过手术切除后也可能复发.为延长患病犬的生命,我们可以选用化疗药物来抑制肿瘤细胞的增殖.长春新碱(vincristine,VCR)是常用的抗肿瘤药物,现已发现可以抑制一些人肿瘤细胞的增殖[2-3],并可以影响一些细胞的周期[4-5].VCR是否对体外培养的犬乳腺癌细胞有抑制作用,国内还未见有这方面的报道,为此,我们进行了这方面的研究. 相似文献
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家蚕中肠上皮细胞增殖和分化的初步研究 总被引：1，自引：0，他引：1
通过分析家蚕自幼虫期到蛹期发育过程中肠上皮细胞的增殖与分化情况,鉴定家蚕中肠干细胞的潜在定位。采用苏木精和伊红(Hematoxylin and Eosin,H&E)染色与4’,6-二脒基-2-苯基吲哚(4’,6-diamidino-2-phenylindole,DAPI)染色追踪变态和发育时期家蚕中肠的形态结构及细胞组成变化,结果显示,幼虫经历蜕皮及变态时,中肠形态结构以及中肠上皮细胞组成均发生明显变化:在幼虫每个龄期的盛食期肠壁较薄,眠前期(蜕皮前)明显变厚,至眠期其厚度达到峰值;中肠上皮层存在柱状细胞(CC)、杯状细胞(GC)和再生细胞(RC)3种细胞,3种类型细胞随龄期逐渐增多,其中各龄期柱状细胞持续增多,至眠期达到峰值,靠近基底膜的小细胞在眠前期增多。利用5-溴脱氧尿嘧啶核苷(5-Bromo-2-deoxyUridine,BrdU)和磷酸化组蛋白(Phospho-histone H3,PHH3)免疫荧光染色检测到中肠上皮细胞,尤其是中肠上皮层靠近基底膜处的小细胞在幼虫各龄眠前期的增殖率最高。同时通过BrdU滞留标记实验在中肠上皮层靠近基底膜处发现了BrdU滞留阳性信号。研究结果发现家蚕幼虫蜕皮时中肠上皮层靠近基底膜处的小细胞发生快速增殖,推测这些小细胞中存在着潜在的家蚕中肠干细胞。 相似文献
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亚慢性铝暴露对雏鸡肝脏结构与功能的影响 总被引：1，自引：0，他引：1
长期慢性铝暴露可致机体内铝蓄积,从而对机体造成损伤.铝毒作用最主要的靶器官是神经系统,此外还可造成肝、血液、肾、骨、免疫等多组织的损伤[1].有研究表明,进入动物体内的铝能够很快在肝脏内蓄积并且抑制肝脏正常功能[2],但目前关于铝对肝脏结构和功能影响的报道甚少,且主要集中在试验动物鼠和兔上,在禽类尚未见研究报道.本试验通过连续腹腔注射固定体积不同浓度梯度三氯化铝法,建立不同程度雏鸡亚慢性铝中毒模型,通过对血清中肝功能酶丙氨酸氨基转移酶(ALT)和天门冬氨酸氨基转移酶(AST)活性、总蛋白(TP)、白蛋白(ALB)、总胆红素(TBIL)和直接胆红素(DBIL)含量及肝脏组织学的观测,旨在探讨铝暴露对鸡肝脏结构及功能的影响. 相似文献
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犬肝脏肿瘤的诊断与治疗 总被引：1，自引：1，他引：0
犬肝脏肿瘤大多为转移性肿瘤.原发性肝脏肿瘤比较罕见,在全部肿瘤患犬中,所占比例不足1%[1].犬原发性恶性肝脏肿瘤组织学分为肝细胞癌、胆管癌、神经内分泌癌和肉瘤[2].其他类型的犬肝脏肿瘤有淋巴肉瘤[3],肝母细胞瘤[4],浆细胞瘤[5]等.最常见的原发性肝脏肿瘤为肝细胞癌,随犬年龄的增大肝细胞癌发病率增高,大多数患犬年龄大于10岁,公犬略多于母犬[6-7].犬肝细胞癌临床症状无特异性[8],但实验室诊断与热稳定的碱性磷酸酶有关[9].将中国农业大学动物医院手术治疗肝脏肿瘤患犬报道如下. 相似文献
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生物素-亲和素放大免疫检测方法是在常规免疫检测的基础上[1-3],结合生物素-亲和素系统(biotin-avidin system,BAS)的高度放大作用,而建立的一种检测系统.目前,BAS技术在兽药残留检测中已有研究报道[4],而在生物学领域已经得到广泛应用,成为当今生物医学研究工作中最具使用价值和发展前途的技术之一[5-9]. 相似文献
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随着鱼类社会需求量的增加及自然环境的破坏 ,鱼类自然资源明显减少。为了弥补自然资源不足和满足市场需求 ,并且对其增殖和资源保护提供一定的参考资料 ,从 50年代以来 ,国内外许多学者对多种鱼类的性腺发育及其周年变化进行了研究 ,其中关于雌性性腺 (卵巢 )的研究较多。1 卵母细胞的发育1 1 卵母细胞的发育分期对于硬骨鱼类生殖细胞和生殖腺发育阶段的分期 ,苏联、日本和美国都提出过分期的方法和标准 ,比较起来并不完全一致。我国的水产工作者基本上都是按照Мейен(1 939)提出的标准来划分的。Мейен认为 ,从卵原细胞到成熟… 相似文献
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魏静 《四川畜牧兽医学院学报》2009,(4):28-32
在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。 相似文献
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本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。 相似文献
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REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air. 相似文献
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Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF
Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo. 相似文献
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乳酸杆菌作为益生菌广泛用于人和动物.本文综述了乳酸杆菌改善宿主健康的机制.乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道.文章重点讨论了乳酸杆菌表面成分(表面蛋白、脂磷壁酸和肽聚糖)与肠道受体(C型凝集素受体、Toll样受体和Nod样受体),阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制. 相似文献
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Billinghurst RC Brama PA van Weeren PR Knowlton MS McIlwraith CW 《American journal of veterinary research》2004,65(2):143-150
OBJECTIVE: To determine whether serum concentrations of biomarkers of skeletal metabolism can, in conjunction with radiographic evaluation, indicate severity of osteochondrosis in developing horses. ANIMALS: 43 Dutch Warmblood foals with varying severity of osteochondrosis. PROCEDURE: 24 foals were monitored for 5 months and 19 foals were monitored for 11 months. Monthly radiographs of femoropatellar-femorotibial and tibio-tarsal joints were graded for osteochondral abnormalities. Serial blood samples were assayed for 8 cartilage and bone biomarkers. At the end of the monitoring period, foals were examined for macroscopic osteochondrosis lesions. RESULTS: Temporal relationships were evident between certain serum biomarkers and osteochondrosis severity in foals during their first year. Biomarkers of collagen degradation (collagenase-generated neoepitopes of type-II collagen fragments, type-I and -II collagen fragments [COL2-3/4C(short)], and cross-linked telopeptide fragments of type-I collagen) and bone mineralization (osteocalcin) were positive indicators of osteochondrosis severity at 5 months of age. In foals with lesions at 11 months of age, osteochondrosis severity correlated negatively with COL2-3/4C(short) and osteocalcin and positively with C-propeptide of type-II procollagen (CPII), a collagen synthesis marker. Radiographic grading of osteochondrosis lesions significantly correlated with macroscopic osteochondrosis severity score at both ages and was strongest when combined with osteocalcin at 5 months and CPII at 11 months. CONCLUSIONS AND CLINICAL RELEVANCE: The ability of serum biomarkers to indicate osteochondrosis severity appears to depend on stage of disease and is strengthened with radiography. In older foals with more permanent lesions, osteochondrosis severity is significantly related to biomarker concentrations of decreased bone formation and increased cartilage synthesis. 相似文献