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61.
Alkaline phosphatase (APase) activity in tissue samples, with adherent bacteria, was measured from two sites in the rumen and from two sites in the abomasum of 57 yearling Angus and Hereford bulls and heifers fed a high or a low energy diet. In the rumen, APase activity was higher at the caudoventral blind sac than at the dorsal sac in animals of both breeds fed the high energy diet and in Angus bulls fed the low energy diet, but the reverse was observed in Hereford bulls fed the low-energy diet (P less than .01). In the abomasum, APase levels were higher for bulls than heifers (P less than .01) and higher at the fundic than at the pyloric region (P less than .01). Morphological studies also showed that rumen samples from animals fed a high energy diet exhibited a more widely distributed APase activity and an increase in the digestive recycling of epithelial cells that produced some "pitting" of the tissue. The higher APase activity of the epithelial tissue of animals fed the high energy diet may be explained by the greater rate of cell death and renewal indicated by the higher mitotic index reported by other researchers who have studied the cell cycle of the rumen epithelium in ruminants fed high and low energy diets. 相似文献
62.
三年来作者对于幼龄結果油棕的果穗和果实腐烂的症状、分布、蔓延为害,其发生条件和栽培管理的关系进行了詳細的調查和观察,并进行了病原分离、培养、田间人工接种和試探性化学保护等試驗。同时对果实离层組織的形成进行了切片检查。 結果指出海南十二个地区的幼龄结实棕园普遍出現的花、果、穗腐与环境条件和栽培管理有密切关系。果腐是果实离体后从蒂部組織开始的。从腐果組織中經常可以分离到細菌、炭疽菌和鐮刀菌。多次田間接种証明这些菌对健康果实和果穗均无致病能力。大田喷药无效。看来,油棕果腐病是由于环境坏、管理差的条件下,未成熟或接近成熟的果实产生离层而与果柄分离,再由外界杂菌腐食脫果而致腐烂。可見,本病是屬于非侵染性的生理病害。 相似文献
63.
1962年秋,作者等在南昌近郊,从感病长果种辣椒的果上,分离到两种炭疽病菌。一种分生孢子为椭圓形(以下簡称G菌),病斑圆形或椭圓形,凹陷,灰綠色或黄色,以后变棕色。另一种分生孢子为鐮刀形(以下簡称V菌),病斑不定形,暗棕色至黑色。这两种病菌,在馬鈴薯、洋菜培养基上都能形成孢子,且对辣椒都有寄生性。 相似文献
64.
1962年在北京夏玉米上用顆粒剂防治玉米钻心虫的結果表明:心叶末期施5%DDT顆粒剂,防治一次,每株2克,在一般年份,从产量上来看是很有利的。同时对药剂残效,幼虫在玉米不同生育期植株上的分布,以及顆粒剂在心叶期施药至抽雄后在植株上的分布测定,并結合顆粒剂小区防治試驗。分析結果说明:心叶末期施药,影响药效的主要原因,不是5%DDT残效的問題,而是抽雄后药剂在植株上部分布較少,尤其是包在雄穗节外的第一叶腋没有药,而此时期,幼虫在植株上部分布較多,同时DDT速效也不如666。 相似文献
65.
天津地区鸡大肠杆菌病病原分离及病原特性 总被引:1,自引:0,他引:1
从天津地区10个区县、23个养鸡场的241只疑似大肠杆菌病病例中,分离出病原菌92株,所得菌株符合大肠杆菌的微生物学特性。致病性在各菌株间略有差异。分离菌对氟哌酸、庆大霉毒、氯霉素最为敏感。抗“O”血清型鉴定,结果表明,分离菌株分属25个血清型,并以O111、O89、O86、O30、O78为主。从优势血清型中选取的菌株,均具有良好的抗原性。 相似文献
66.
K-S. Dai C-S. Liang Y. T. Ch'iu P-C. Yang I. C. Cheng 《Veterinary research communications》1995,19(2):115-125
The purpose of this study was to determine whether myocardial adenosine triphosphatase (ATPase) activities were reduced in pigs with naturally occurring hypertrophic cardiomyopathy (HCM). The selection of hearts for the HCM and the normal control groups depended on histological examination. Specific ATPase activity and 5-nucleotidase activity were measured in left ventricular myocardium obtained from HCM (n=7) and normal control (n=7) animals. The histological features of HCM included marked disorientation of muscle cells, thickening of the intramural coronary arterial wall with a narrowed lumen, endocardial fibrosis and myocardial fibrosis. The HCM group showed significant increases in both heart weight (32%) and heart weight to body weight ratio (46%). The total ATPase activity in crude homogenates from the HCM group was significantly decreased by 16%. Azide-sensitive ATPase (mitochondrial ATPase) activity, ouabain-sensitive ATPase (Na+,K+-ATPase) activity, basal Mg2+-ATPase activity and Ca2+-ATPase activity were all significantly decreased by 18%, 30%, 20% and 50%, respectively. In contrast, no significant decrease was found in the mean values for 5-nucleotidase activity. These results suggest that myocardial ATPase activities are suppressed in pigs with naturally occurring HCMAbbreviations ATP
adenosine triphosphate
- gww
grams wet weight
- HCM
hypertrophic cardiomyopathy
- Pi
inorganic phosphate 相似文献
67.
68.
土地资源结构与农林牧合理用地布局的探讨——以甘肃省河西走廊为例 总被引:1,自引:0,他引:1
申元村 《干旱区资源与环境》1992,(2)
本文以土地资源结构理论为依据,论述了甘肃省河西走廊地区的农业分区,土地资源质量数量结构、农林牧合理用地构成及区域开发的整体布局。 相似文献
69.
Summary Aseptically cultured shoots of Chinese gooseberry exhibited growth disorder and morphological aberrances, and some died after being exposed to sufficient gamma-ray irradiation. The death rate was dose dependant and the LD50 was 80–90 Gy and 50–60 Gy respectively for cv. Hayward and clone 4. All petiole explants irradiated with gamma-ray could form calli as the control, but the rate of differentiation of adventitious shoots of the petiole explants decreased and was dependant on dose. Sensitivity of the shoot or petiole explants to gamma-ray irradiation varied with species. Gamma-ray irradiation did not deter either the 2-node segments from producing axillary shoots M1, M2, and M3 or the advantitious shoots originating in the petiole explants and the M3 shoots from forming advantitious roots. Therefore, using aseptically cultured axillary or adventitious buds for mutation breeding of Chinese gooseberry is feasible. A bacterium surviving in the explants lessened the efficiency of these two in vitro techniques in mutation breeding of Chinese gooseberry.Abbreviations IAA
3-indole acetic acid
- IBA
-indole butyric acid
- MS
Murashige & Skoog (1962) 相似文献
70.
L.K. Cutkomp D. Desaiah E.Y. Cheng E.V. Vea R.B. Koch 《Pesticide biochemistry and physiology》1976,6(3):203-208
American cockroaches injected with sublethal doses of DDT (0.75 μg/roach) at 5-day intervals showed a 40% reduction in oligomycin-sensitive Mg2+ATPase from muscle homogenates, and a 23% reduction of Na+-K+ATPase from nerve cords. Thus, the maximum effect measured occurred with the same enzyme and tissue as determined from in vitro studies. The metabolite, DDE, used at 15 μg per roach, gave no significant change in activity of the ATPase system following injection. In contrast, high single doses of DDT (7.5 μg/roach) and 100 μg DDE and dicofol per roach caused over 30% increase in oligomycin-sensitive Mg2+ATPase of muscle and a 10–15% increase in Na+-K+ATPase of nerve cords measured 24 and 48 hr later. While a similar response was observed for Mg2+ATPase activities in cockroaches that were immobilized, the increase in enzyme activities were much greater than that caused by the pesticides. 相似文献