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991.
灰色关联分析在草坪草引选评价上的应用 总被引:5,自引:2,他引:3
根据灰色理论和应用数列间的相似程度来判断两个系统或系统中的两个因素之间关联程度的原理,在对引进的3个草坪草种(14个品种)多种性状观测及分析的基础上,计算求得各性状的关联系数ε1(k)及关联度γi,综合评价各引选品种,由定性评价转为定量评价。结果表明,在贺兰山东麓地区,表现较好的草坪草种有:草地早熟禾类的瓦巴斯、菲尔京、纳苏、爱肯尼4个品种:紫羊茅中的巴可紫羊茅、高羊茅中的梯坡,巴法7851两个品 相似文献
992.
Application of Trichoderma harzianum, to soil or by coating tomato fruits, reduced Rhizoctonia solani fruit rot by up to 43% and 85%, respectively, under laboratory conditions. When mixed with naturally infested soil, Trichoderma reduced R. solani inoculum potential by 86% in field trials. It also significantly reduced fruit rot by 27–51%. 相似文献
993.
Y Ruckebusch L A Ooms A D Degryse C Allal 《American journal of veterinary research》1985,46(2):434-437
The relationships between forestomach motility and eructation rate were studied in sheep and cattle. Three ewes and 2 heifers were implanted with strain gauges on the reticulo-rumen and fitted with a cannula in the dorsal sac of the rumen. Studies were performed in sheep after induction of hypocalcemia by Na2EDTA infusion and cattle were studied after ruminal distension. Experiments were performed by measuring the rate and volume of eructated ruminal gases, using a technique by which the trachea is transected. The frequency of reticulo-ruminal contractions decreased 40% within 30 minutes of Na2EDTA infusion to the sheep. The volume of eructated gas (for 30-minute periods) decreased from 10.7 L to 5.5 L at the end of the 60-minute infusion period. Pretreatment with ritanserin (0.1 mg/kg, subcutaneously) not only prevented bloating during the ruminal stasis induced by hypocalcemia, but also significantly increased the eructated volume of gas. In cattle, ritanserin given at the same dose level (0.1 mg/kg, subcutaneously) significantly increased the volume of eructated gas after ruminal distension. This study supports the hypothesis that the caudal esophageal sphincter has a role in the rate of ruminal gas eructation and indicates that its relaxation may be due to a 5-hydroxytryptamine antagonist. 相似文献
994.
Crystal violet staining of Bordetella bronchiseptica colonies for differentiation of phase-I strains from variant strains in degraded phases. 下载免费PDF全文
After 2 days of growth on Brain heart infusion agar (BHIA) at 38 degrees C, phase-I colonies and degraded-phase colonies of Bordetella bronchiseptica could be differentiated by their ability to take up crystal violet (CV). Phase-I colonies in X mode, but not colonies in degraded phases (phases II, III, and rough) bound CV. Phenotypically-altered C-mode colonies (grown at 32 degrees C or lower temperatures) also lacked this ability. CV staining offers an easy method for the recognition of different colony types that appear identical when observed on BHIA. 相似文献
995.
Histologic and immunocytochemical study of endocrine cells in the gastrointestinal tract of the cow and calf 总被引:3,自引:0,他引:3
N Kitamura J Yamada N Y Calingasan T Yamashita 《American journal of veterinary research》1985,46(6):1381-1386
The regional distribution and relative frequency of argyrophil cells, and of cells immunoreactive for 5-hydroxytryptamine (5-HT), substance P (SP), somatostatin, glicentin, glucagon, bovine pancreatic polypeptide (BPP), gastrin, leucine-enkephalin, gastric inhibitory polypeptide (GIP), cholecystokinin, secretin, motilin, and neurotensin were studied in 9 segments from the gastrointestinal tract of cows (greater than 1 year old) and calves (less than 3 months old). Argyrophil cells, 5-HT-immunoreactive cells, and somatostatin-immunoreactive cells were distributed throughout the gastrointestinal tract, whereas the other immunoreactive cells were more restricted in distribution. Most endocrine cells were more numerous in the calf than in the cow. This feature was most conspicuous in the abomasum. In the abomasum, argyrophil cells in the cow and calf and 5-HT-immunoreactive cells in the calf were found predominantly in the fundic region, whereas somatostatin-immunoreactive cells and gastrin-immunoreactive cells in the cow and calf and 5-HT-immunoreactive cells in the cow were most numerous in the pyloric region. Substance P-, glucagon-, BPP-, and leucine-enkephalin-immunoreactive cells were rarely detected. In the small intestine, argyrophil cells, 5-HT-, SP-, somatostatin-, gastrin-, GIP-, cholecystokinin-, secretin-, and motilin-immunoreactive cells were most numerous in the duodenum. Neurotensin-, glicentin-, glucagon-, and BPP-immunoreactive cells were detected with the highest frequency in the ileum. In the large intestine, argyrophil cells and 5-HT-, glicentin-, BPP-, somatostatin-, glucagon-, and SP-immunoreactive cells occurred with the highest frequency in the rectum. 相似文献
996.
To investigate the factors contributing to the different ovulation rates observed in two strains of sheep (Booroola 5.2, Merino, 1.2) and after immunization against androstenedione (Immunized 1.8, Control 1.3), in vivo monitoring of follicular kinetics followed by histological examination of the ovaries was performed during the late luteal and follicular phases. Ewes had the three largest follicles of each ovary ink-labelled at days 13 and 15 and were ovariectomized after the beginning of oestrus.High ovulation rate was not associated with a more numerous antral follicle population in either Booroola ewes or immunized ewes. Furthermore, in Booroola ewes (r = 0.22) and in immunized ewes (r = ?0.02), there was no correlation between the number of antral follicles per ovary and the ovulation rate.The reasons for the high ovulation rate became clear when preovulatory enlargement was followed by ink-labelling. An extended period of time during which recruitment of ovulatory follicles takes place, together with a low incidence of selection through atresia and the ability of fully grown follicles to wait for ovulation are the features involved in the high ovulation rate of the Booroola ewes. A lower incidence of selection together with an unaltered recruitment leads to the increased ovulation rate noticed after immunization. 相似文献
997.
998.
农业院校法学本科教育是法学教育体系不可分割的部分,农业院校培养的法学人才对填补农村法治人才真空、提供农村社会发展外源性力量具有重要意义。当前农业院校法学本科教育存在着法学教育的通病,同时又面临基础不厚实、培养目标模糊等困境。农业院校法学本科教育应确立合适的培养目标,发挥比较优势,加强社会交流,争取社会认可,推动教学改革,深化涉农法学研究,建设特色精品课程。 相似文献
999.
给出了一种提取广义开关网络中两节点间“最小”连接矩阵的方法.该方法采用广度优先和深度优先结合遍历提取出两顶点间的连接矩阵,再结合Tarjan拓扑图块划分算法和“不跨越已知割点遍历”思想降阶使矩阵达到“最小”.将继电控制线路抽象为开关网络,通过连接矩阵计算出驱动元件的开关函数,从而掌握电气信息.使用“批”的概念描述继电控制线路中的事件时序.基于以上两点,再利用继电控制线路图上表达出的驱动元件与开关之间的关系,可实现对继电控制线路进行功能分析的CAD方法. 相似文献
1000.
Al-Eknah M.M. Homeida A.M. Dafalla E.A. Galil A.K.A. Al-Tahir A.Y. 《Veterinary research communications》1997,21(1):45-50
Al-Eknah, M.M., Homeida, A.M., Dafalla, E.A., Galil, A.K.A. and Al-Tahir, A.Y., 1997. Uterine activity after induction of hypocalcaemia in the ovariectomized camel (Camelus dromedarius). Veterinary Research Communications, 21 (1), 45-50.Bilateral ovariectomy was performed in three parous, non-pregnant camels. Intrauterine and intra-abdominal pressure changes were recorded using balloon-tipped catheters. Uterine contractions were induced and maintained in the ovariectomized camels by daily intramuscular injections of 5 mg oestradiol benzoate throughout the experimental period. The frequency of uterine contractions varied from 6 to 9 per minute, whereas the amplitude varied from 2 to 3 kPa in all the animals. Inducing hypocalcaemia to a level of 0.5 mmol/L by Na2EDTA reduced the amplitude of the contractions to below 1 kPa (p<0.001). The frequency of the contractions was not affected. 相似文献