乳腺分泌物中体细胞的研究进展

不同物种的乳腺分泌物中含有的细胞成分被称为体细胞,其中包括淋巴细胞、白细胞、巨噬细胞和上皮细胞。物种、乳腺感染情况、不同生理阶段和饲养管理条件等因素均会影响乳中的体细胞数量和细胞类型。近年来,乳中体细胞得到了人们的关注和深入研究,显示出广阔的应用前景。人们利用从初乳和常乳中得到的乳腺上皮细胞已经成功进行了乳腺细胞的原代培养和建立了乳腺细胞系,为乳生成、被动免疫转移和乳腺癌的研究提供了良好平台。体细胞中提取的RNA代表了乳腺组织的基因表达,因此为研究乳腺组织的基因表达提供了方便、良好的来源。     

亚洲璃眼蜱差异表达新基因P18的克隆和鉴定

为了进行抗蜱和蜱传病疫苗的研究,本实验对亚洲璃眼蜱雌蜱吸血前后唾液腺消减文库中获取的一个全长编码基因P18进行了研究。该基因全长519bp,共编码170个氨基酸,分子量为18.36Ku,等电点为4.28。BLAST分析表明,该基因预测的氨基酸与肩突硬蜱、篦子硬蜱唾液腺的抗凝血小肽有30%～40%低度同源性。将该基因亚克隆到pET-32a( )表达载体,转化BL21(DE3)宿主菌,经IPTG诱导,重组融合蛋白以可溶性形式高效表达。将可溶性重组蛋白免疫小鼠后获得的抗血清。经免疫印迹分析表明,该重组蛋白抗体可特异性的识别半饱雌蜱唾液腺中的天然蛋白抗原,而未吸血雌蜱唾液腺中则不显现特异条带。RT-PCR结果进一步证实,该基因在蜱吸血后的唾液腺中差异表达。     

北京鸭胰液分泌昼夜变化规律研究

为了研究北京鸭的胰腺外分泌的昼夜变化规律,通过肠-胰(第一胰管)瘘管,全天分8个时间段收集胰液,分别测定胰液的分泌量、胰液pH值、总蛋白含量、HCO3-浓度、胰蛋白酶、胰脂肪酶和胰淀粉酶活性。结果显示北京鸭的胰液是一种具有较大缓冲容量的缓冲溶液,为各种消化酶提供了适合的酸碱环境。胰液中的各种消化酶的变化规律各异,和饲喂之间的关系不明显。     

温室丝瓜泌蜜规律的初步研究

通过对温室丝瓜泌蜜规律的调查研究,结果表明,在7:00～15:00之间丝瓜花泌蜜高峰期是上午7:00～9:00,9:00达到高峰值,之后基本上不再泌蜜.泌蜜量与温度、湿度相关性很小,差异不显著.雄花花蜜浓度变化和湿度变化存在一定负相关,相关系数r=-0.749,差异达到显著水平(P＜0.05);雌花花蜜浓度和湿度亦呈现负相关,相关系数r=-0.884,差异达到极显著水平(P＜0.01).花蜜浓度的变化和温度存在一定正相关,但差异未达显著水平.花的直径大小对泌蜜量的影响迭极显著水平(P＜0.01).     

Adrenocorticotropic hormone-induced secretion of cortisol in goats is inhibited by androgen

In a previous study, it was found that there are sex differences in goats with respect to the levels of cortisol secretion induced by transportation stress. We also found that treatment of castrated male goats with dihydrotestosterone (DHT) suppressed the increase in plasma cortisol concentration following transportation, but did not suppress the secretion of adrenocorticotropic hormone (ACTH). This suggests that androgen might block ACTH ‐ induced cortisol secretion. In order to examine this hypothesis, the effects of androgen on ACTH‐induced cortisol secretion in goats were investigated. First, castrated male goats were treated with testosterone (T), DHT or cholesterol (cho) for 21–25 days. Cho was used as a control for T and DHT treatment. Then, plasma cortisol concentrations were compared among the hormonal treatments after ACTH injection. Subsequently, the distribution of androgen receptors in the caprine adrenal gland was investigated. There were no differences in the basal cortisol concentrations among the hormonal treatments. However, plasma cortisol concentrations after ACTH injection were significantly lower in T ‐ and DHT ‐ treated goats than in cho ‐ treated goats. Androgen receptors were present in 60% of the cells in the zonae fasciculata and reticularis of the adrenal cortex, the regions that secrete glucocorticoids. These results suggest that androgen may act directly on the adrenal cortex to suppress cortisol secretion induced by ACTH.     

采前喷钙和套袋对华盛顿脐橙果皮病变的影响

以华盛顿脐橙为试验材料,研究了采前喷钙和套袋对果皮病变的影响。结果表明,华盛顿脐橙果皮油胞凹陷和油胞破裂等田间果皮病变高达30%以上;果皮病变与果园管理水平、植株和果皮钙含量密切相关,采前喷钙和套袋处理提高了果实硬度,增加果皮钙含量,降低采后果皮病变率40%～50%,达显著和极显著水平;同时钙处理促进果实着色,显著增加果皮红色度和光泽度。采前喷钙和套袋对提高华脐果实的外观品质和商品性具有很好的作用。     

胭脂蚧的形态特征及蜡泌物超微结构的研究

采用制作玻片标本和扫描电镜技术研究了胭脂蚧Dactylopius confusus（Cockerell）在不同发育阶段的显微形态特征及蜡泌物的超微形态。结果发现：1龄若虫，它的五格腺分布全身，管腺有少量分布；背刺为柱状或截锥状，呈带状分布。雌成虫，它的管腺分布整个腹面，五格腺在腹面末端成簇，在背面单个或成群分布；背刺散布全身。蜡泌物的研究发现：若虫背腹面均分泌丝状蜡，断裂后形成C型小蜡圈；背刺实为中空管，具泌蜡功能。雄茧是由蜡丝交织构成。雄蛹表面附着白色蜡粉。而雌成虫蜡被是由粗蜡管及其周围的细长蜡丝组成。     

转EGFP基因山羊克隆胚的发育

利用脂质体包裹含EGFP基因的质粒,并将之导入山羊乳腺上皮细胞,经G418筛选获得阳性细胞,以阳性细胞作为核供体,利用核移植技术构建转基因克隆胚。结果表明：用转基因山羊乳腺上皮细胞作为核供体,电融合法更适合构建转基因克隆胚。转基因山羊克隆胚体外培养最佳方案是用SOFaa培养液,在培养72 h后加入10%的正常山羊血清（Normal goat serum,NGS）。荧光显微镜下观察到转基因克隆胚中EGFP的表达,大部分克隆胚发育到8-16细胞以后的时期,绿色荧光蛋白才开始逐渐表达,随着发育时间的延长,绿色荧光蛋白的表达也逐渐增强。说明外源基因在胚胎早期发育阶段可以表达,EGFP可以作为报告基因来实现对外源基因整合及表达的监测。     

Stimulation of the bronchus-associated lymphoid tissue of goats and its effect on in vitro colonization by Pasteurella haemolytica

Twenty goats of about 7 months of age were divided into five groups. The goats in groups 1 and 2 were exposed once, using an intranasal spray to 2 ml of an inoculum containing 10⁶ colony-forming units/ml of living or dead Pasteurella haemolytica A2, respectively. The goats in groups 3 and 4 were similarly exposed twice at a 2-week interval. Group 5 was the untreated control. The number and size of the bronchus-associated lymphoid tissue (BALT) in goats exposed twice to either living or dead organisms were significantly (p>0.05) increased compared with those exposed once and with the unexposed control. In vitro colonization by living P. haemolytica A2 onto the lung tissue in which the BALT had been stimulated by two exposures of either living or dead organisms was significantly (p>0.05) reduced. The study indicates that stimulation of the respiratory mucosal immunity may prevent P. haemolytica A2 infection.     

ULTRASONOGRAPHIC DETECTION OF ADRENAL GLAND TUMOR AND URETEROLITHIASIS IN A GUINEA PIG

A 5-year-old guinea pig was presented to the University of Berne Small Animal Radiology Department for an ultrasound examination of the abdomen to confirm a suspected diagnosis of Cushing's syndrome. The patient had bilateral alopecia, was apathic and obese. Ultrasonographically, a tumor of the left adrenal gland, obstruction of the left ureter by an ureterolith, as well as hydronephrosis of the left kidney were detected. During surgery to relieve the ureteral obstruction the adrenal gland tumor was removed. The guinea pig died post-operatively due to blood loss. The left adrenal gland tumor was found histopathologically to be an adenoma and the right adrenal gland also had multiple small adenomas, but grossly appeared normal. The ureterolith was analyzed and found by x-ray diffraction to consist of calcium carbonate.