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排序方式: 共有407条查询结果,搜索用时 15 毫秒
111.
Fukuzawa R Fukuzawa K Abe H Nagai T Kameyama K 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2004,33(1):39-42
Abstract: A male African pygmy hedgehog ( Atelerix albiventris ), estimated to be 3 years old, presented with exophthalmos and fixed abduction of the right eye. Radiographic examination revealed a retrobulbar tumor in the right orbital cavity. The mass was surgically resected but recurred 3 months later and the hedgehog died. There was no gross or microscopic evidence of salivary or lacrimal gland involvement of the tumor at surgery or at necropsy. The histopathologic, immunohistochemical, and ultrastructural findings were those of acinic cell carcinoma, the origin of which was unknown. This is the first known case of acinic cell carcinoma in an African hedgehog. 相似文献
112.
一种鉴定α—淀粉酶活性及其产生菌的新方法 总被引:12,自引:0,他引:12
锥虫蓝法是利用锥虫蓝和淀粉交联生成蓝色复合物,淀粉经α-淀粉酶水解后蓝色褪去,出现透胆水解圈这一原理来鉴定α-淀粉酶及其产生菌的。与碘淀粉法的不同之处在于:本法对淀粉酶及其产生菌无任何不良影响。该交联复合物可以经加压灭菌处理;锥虫蓝的适宜使用浓度为0.005%~0.01%(W/V);培养基使用量为15ml/皿左右(ψ80mm)。锥虫蓝法的灵敏度和使用范围与碘淀粉法相同,但以锥虫蓝和淀粉配制的鉴别培养基,在筛选淀粉酶基因时优于常规的碘淀粉法。 相似文献
113.
采用聚丙烯酰胺凝胶垂直平板电泳法对379头青海黄牛血清淀粉酶的多态性进行了研究。结果发现:⑴青海黄牛存在AMY1,AMY2和AMY3三种同工酶,但只有AMY1同工酶存在多态性;⑵AMY1同工酶受AMY1^B和AMY1^C一对共显性等位基因控制,两者的基因频率分别为0.5277和0.4723;⑶柴达木黄牛AMY1同工酶的多态性特征与青海东部黄牛相同。 相似文献
114.
为了研究饲料中添加复合酸化剂对黄羽肉鸡消化道酶活性的影响,选择160只1日龄黄羽肉鸡,按公母比例一致的原则,随机分成A、B、C、D4个处理组.A组饲喂基础日粮,B、C、D组分别饲喂在基础日粮中添加0.2%、0.5%、0.8%由乳酸、柠檬酸、富马酸组成(50∶ 35:15)的复合酸化剂的日粮,在14、28、42、56日龄时测定胃内容物蛋白酶活性,十二指肠和空肠内容物淀粉酶、二糖(麦芽糖)酶和脂肪酶活性.结果显示:与A组相比,B组14日龄的腺胃内容物蛋白酶活性显著提高72.61%;C组28日龄的肌胃内容物、14日龄的腺胃内容物蛋白酶活性分别显著提高38.64%、69.55%;D组28、56日龄的肌胃内容物及14日龄的腺胃内容物蛋白酶活性分别显著提高46.25%、49.65%、92.84%.复合酸化剂对十二指肠和空肠内容物淀粉酶、二糖(麦芽糖)酶和脂肪酶活性均无显著影响.可见,复合酸化剂可显著提高黄羽肉鸡胃内容物蛋白酶活性. 相似文献
115.
Liu Hua-long Sha Han-jing Wang Jing-guo Liu Yang Zou De-tang Zhao Hong-wei 《东北农业大学学报(英文版)》2014,21(3):1-6
To explore the germination mechanism of salt-stressed rice improved by exogenous proline, and provide a theoretical basis to rice direct sowing technology for salinized soil, the effects of soaking with proline on germination status, amylase activity and isoenzyme were studied in this paper. The results showed that germination status including germination energy(GE), germination rate(GR), relative germination energy(RGE) and relative germination rate(RGR) significantly decreased as the same as the activities of alpha-amylase, beta-amylase and the total amylase under salt stress. Soaking with exogenous proline improved the germination status of rice under salt stress. Moreover, GE and RGE of salt-stressed rice were improved with increasing of proline concentration at the range of 5-45 mmol ·L-1. Soaking with 15 mmol ·L-1 and 30 mmol ·L-1 proline significantly improved the amylase activities(e.g. alpha-amylase, beta-amylase and total amylase) of rice under salt stress. Salt stress inhibited the express of beta-amylase isoenzyme temporarily, but had few impacts on alpha-amylase isozyme. Soaking with 30 mmol ·L-1 proline brightened District I and increased the width of 'i' brand in District II of alpha-amylase isoenzyme, but had few impacts on beta-amylase isoenzyme. In a word, soaking with proline could effectively alleviate the inhibitory effects of salt stress on seed germination. 相似文献
116.
The authors described a novel submerged batch culture system that produced high levels of amylase by Aspergillus kawachii using whole barley (WB), the surface of which is covered by its husk. In this study, detailed analyses determining the amylase activities, residual sugars, fungal morphology and expression levels of genes were performed in a submerged culture using WB to address the mechanism underlying high amylase productivity in A. kawachii. High levels of glucoamylase and acid-stable u-amylase were produced in this culture, and expression levels of amylases, as well as glucose-repressive genes including high-affinity glucose transporter and peroxidase/catalase were also high. On the other hand, the morphology of mycelia was altered, with swollen, bulbous, multi-septum hyphae and conidiophores that normally form in a solid culture being partially generated. Furthermore, cell cycle and post-translational modification-related gene expression levels were altered, and were similar to those in the solid culture. These findings suggest that high amylase productivity in the submerged culture using WB is accompanied by both the up-regulation of amylase genes and activation of post-translational modifications due to fungal morphological changes being brought closer to those in the solid culture. 相似文献
117.
采用酶学方法测定了不同性腺发育时期(Ⅱ~Ⅴ期)小体鲟Acipenser ruthenus Linnaeus雌性亲鱼胃、肠道和幽门盲囊中蛋白酶、淀粉酶、脂肪酶的活性,并分析了3种酶活性随性腺发育时期的变化规律。结果表明:小体鲟雌性亲鱼5种消化器官中的蛋白酶活性以性腺发育Ⅱ期、Ⅲ期较高,淀粉酶活性以性腺发育Ⅴ期较高,脂肪酶活性以性腺发育Ⅴ期、Ⅱ期较高,3种酶活性均以性腺发育Ⅳ期较低;各性腺发育期,雌性亲鱼的蛋白酶活性均以幽门盲囊、后肠中较高,其次为胃、中肠,淀粉酶活性以中肠中最高,其次为胃、幽门盲囊、前肠、后肠,脂肪酶活性均以幽门盲囊中最高,其次为中肠、前肠、胃、后肠。研究表明,小体鲟雌性亲鱼在性腺发育Ⅱ期、Ⅲ期对食物中蛋白质和碳水化合物需求较高,而性腺发育周期中对脂类物质的需求Ⅴ期最高,其次是Ⅱ期,总体来说,小体鲟亲鱼在整个性腺发育时期对脂肪的需求量较高。 相似文献
118.
119.
近年来,昆虫淀粉酶抑制剂成为一个新的研究热点,取得了令人瞩目的成果。综述了昆虫淀粉酶抑制剂研究的最新进展。对昆虫淀粉酶抑制剂的类型、分离纯化、活性测定、物理化学特性和抑制特性以及结构与功能的关系等作了概述,并对其应用前景作了展望。 相似文献
120.
为挑选信息含量大、与样品组成或性质相关性较强的光谱区域参与建模,以提高校正模型的精度,采用相关成分分析法对大米直链淀粉的近红外光谱进行分析。结果表明:采用相关成分分析法进行波长选择后,建模波长点数减少为波长选择前的22%,模型预测值与标准值的相关系数R由0.921 2提高到0.973 0,交叉验证标准差(SECV)由3.404 3减小为1.977 4,预测标准差(SEP)由4.810 0减小为1.900 0,模型的预测能力得到显著提高。 相似文献