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木聚糖酶是一类内切糖苷酶酶系,同自然界中五碳糖的循环相联系,在能量循环中占有重要地位。试验通过采用DNS(3,5-二硝基水杨酸)法,在540nm处用紫外分光仪测OD值,对某生物木聚糖酶进行研究,得出该木聚糖酶的最适pH值为4.2;分别在30～85℃测定木聚糖酶酶活,得该木聚糖酶的最适反应温度为50℃。同时发现,该酶的热稳定性较好、耐酸碱性好,木聚糖酶对pH值不敏感。 相似文献
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Bacillus subtilisT15产木聚糖酶的学特性及其在禽饲料中应用的初步研究 总被引：1，自引：0，他引：1
对Bacillus subtilisT15生产的木聚糖酶作了部分酶学性质考察,研究表明该酶是一种中性木聚糖酶,最适pH值为6.4,pH值稳定范围为5.6～8.0;最适温度为55℃,酶液在40～50℃处理4h后活力保持100%,含水量17%～20%的酶泥在85℃条件下2.5min活力保持67.4%;对燕麦木聚糖的主要降解产物为聚合度2～5的木寡糖.在考察酶学性质基础上,对该酶作了在禽饲料中的初步应用实验.饲养试验表明,在禽饲料中添加0.002%该酶能提高料肉比9.94%,饲养效果显著优于对照组(P＜0.05). 相似文献
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Bacillus subtilisT15产木聚糖酶的酶学特性及其在禽饲料中应用的初步研究 总被引：2，自引：1，他引：2
对BacillussubtilisT15生产的木聚糖酶作了部分酶学性质考察,研究表明:该酶是一种中性木聚糖酶,最适pH值为6.4,pH值稳定范围为5.6～8.0;最适温度为55℃,酶液在40～50℃处理4h后活力保持100%,含水量17%～20%的酶泥在85℃条件下2.5min活力保持67.4%;对燕麦木聚糖的主要降解产物为聚合度2～5的木寡糖。在考察酶学性质基础上,对该酶作了在禽饲料中的初步应用实验。饲养试验表明,在禽饲料中添加0.002%该酶能提高料肉比9.94%,饲养效果显著优于对照组(P<0.05)。 相似文献
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木聚糖酶是饲用复合酶制剂中的主要酶种之一,本文对某商品酶制剂中的木聚糖酶进行了酶学性质的研究,这对于木聚糖酶的酶活测定、保存及应用均具有重要的指导意义.实验结果表明:该木聚糖酶的热稳定性良好,最适反应温度为50℃,最适pH为5.0,Km值为4.485 mg/mL,Cu2+、Zn2+、Mn2+和Fe3+对本木聚糖酶有抑制作用,而Na+、K+及(NH4)2SO4能提高此木聚糖酶的活性. 相似文献
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饲用酶制剂中木聚糖酶酶学性质的研究 总被引：4，自引：1，他引：3
木聚糖酶是饲用复合酶制剂中的主要酶种之一，本文对某商品酶制剂中的木聚糖酶进行了酶学性质的研究，这对于木聚糖酶的酶活测定，保存及应用均具有重要的指导意义。试验结果表明：该木聚糖酶的热稳定性良好，最适反应温度为50℃，最适pH值为5．0，Km值为4．485mg/mL,Cu^2 ,Zn^2 ,Mn^2 和Fe^3 对本木聚糖酶的抑制作用，而Na^ ,K^ 及（NH4）2SO4能提高此木聚糖酶的活性。 相似文献
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饲用酶制剂中木聚糖酶酶学性质的研究 总被引：1，自引：0，他引：1
木聚糖酶是饲用复合酶制剂的主要酶种之一，本文对某商品酶制剂中的木聚糖酶进行了酶学性质的研究，这对于木聚糖酶的酶活测定，保存及应用均具有重要的指导意义，实验结果表明，该木聚糖酶的热稳定性良好，最适反应温度为50℃，最适pH为5．0，Km值为4．485mg/mL,Cu^2 ，Zn^2 ,Mn^2 和Fe^3 对本木聚糖酶有抑制作用，而Na^ ,K^ 及（NH4）SO4能提高此木聚糖酶的活性。 相似文献
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The number of donkeys and mules throughout the world is stable, and awareness of their use and concern for welfare, pain recognition and treatment are receiving increasing veterinary interest. Therefore, accurate information about anaesthesia and analgesia in donkeys and mules is important to ever more equine practitioners. Since donkeys are physiologically and pharmacologically different from horses, knowledge on species specific aspects of anaesthesia and analgesia are very important. Mules combine elements from both donkey and horse backgrounds, leading to great diversity in size, temperament and body type. Physiologically, they seem to resemble horses more than donkeys. This review highlights the current knowledge on various anaesthetic and analgesic approaches in donkeys and mules. There is still much information that is not available about donkeys; in many circumstances, the clinician must use available equine information to treat the patient, while monitoring carefully to observe for differences in response to therapy compared to the horse. 相似文献
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The large intestine of 10 cows was examined from the right abdominal wall with a 3.5 MHz linear transducer. The cows were then slaughtered, and the organs were re-examined in a water bath. The caecum was visualised from the middle region of the abdominal wall. It ran caudo-cranially, varied in diameter from 5.2 to 18.0 cm and was situated immediately adjacent to the abdominal wall. The lateral wall of the caecum appeared as a thick, echogenic, crescent-shaped line. It could be visualised as far cranially as the 12th intercostal space. Although its junction could not be identified, the proximal ansa of the colon was recognised on the basis of its anatomical position and its diameter, which was smaller than that of the caecum. The spiral ansa of the colon and the descending colon were situated dorsal to the caecum and could be identified by moving the transducer horizontally along the abdominal wall to the last rib. The spiral ansa of the colon was situated ventral to the descending colon, and its walls appeared as thick echogenic lines. In a contracted state, the spiral colon had the appearance of a garland. 相似文献
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K Militzer 《DTW. Deutsche tier?rztliche Wochenschrift》1990,97(6):239-243
Ethological studies are important means to evaluate the behaviour of small laboratory animals (mouse, rat, guinea-pig and rabbit) and their housing conditions. At any rate, the only sparse range of body expressions, the smallness and preference of night activity of these animals and the erratic occurrence of essential behaviour patterns make the investigations more difficult. On the other hand, the standardization of laboratory housing and the genetic definition of these animals turn out to be favourable. By this way, behaviour-environment-relationships are suitable for evaluation. Taking into consideration methodical and biological restrictions, the specific activities such as fight, relaxed resting behaviour and play as well as unbalanced behaviour patterns and stereotypes can be taken as means of evaluation. Particularly in mice and rabbits, upright position and space consuming activities will be possibly restricted by cage sizes. 相似文献
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Effects of age and diet on the development of the pancreas and the synthesis and secretion of pancreatic enzymes in the young pig 总被引：17，自引：0，他引：17
Effects of age and diet composition on amylase, trypsin and chymotrypsin activities in the pancreas and intestinal contents, pancreas weights and body weights were determined from birth to 56 d. A total of 120 pigs, five to seven pigs/litter from 18 litters, were slaughtered at birth, 14, 27, 29, 31, 42 and 56 d. Litters were allotted to dietary treatments (corn-soy, A; corn-soy + 20% dried whey, B; corn-soy + 5% lard, C) and offered these diets as creep feed at 14 d. All pigs were weaned at 28 d, placed in elevated nursery pens and fed their respective diets. Total activities of amylase, trypsin and chymotrypsin in the pancreas and small intestine increased (P less than .05) with age. Both trypsin and amylase activities, measured per kilogram body weight or gram pancreas weight, were low at 29 d in the intestine and increased to 56 d. Pigs on diet B had the highest level of trypsin and chymotrypsin in the intestinal contents (P less than .05). Trypsin activity in the pancreas (units/kg body weight) was lowest (P less than .05) for pigs on diet B and highest (P less than .05) for those on diet C (units/g pancreas and units/kg body weight). Amylase activity (units/kg body weight) was lower (P less than .05) in the pancreas for pigs on diet B than for those on diets A and C. Pigs on diet A had lower (P less than .01) intestinal amylase activities than those on diets B and C. Enzyme activities in the intestinal contents and pancreas were low following weaning. In the pancreas, activities decreased at 31 d.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Blood and urine samples of 180 dairy cows from 12 herds were examined. Sodium and potassium concentrations were determined in erythrocytes, whole blood, plasma, urine, and glucose concentration in blood: the interrelations were compared. Sodium and potassium concentrations in erythrocytes were 85.15 +/- 11.45 mmol/l, and 25.93 +/- 7.81 mmol/l, respectively. A statistically significant relation was found between sodium and potassium concentrations in erythrocytes (r = 0.3467+++) and the content of electrolyte in blood cells and in whole blood (Na: r = 0.5336+++; K: r = 0.3561+++). No statistically significant relation of intraerythrocyte concentration of both electrolytes was confirmed with respect to the other characteristics (sodium and potassium concentrations in plasma and urine, and glucose concentration in blood). In the conditions of routine laboratory diagnostics in clinically healthy cows, determinations of intraerythrocyte sodium and potassium do not broaden possibilities of evaluating the metabolic state of these electrolytes and cannot be used as the characteristics of energy insufficiency. The cannot replace the analyses performed in serum and urine. 相似文献
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The rate of flow of fluid from the caecum and from the large colon was measured in four Shetland-type ponies fed a hay diet. In two ponies with cannulas in the caecum and at the origin of the right ventral colon, a continuous intracaecal infusion of a solution of chromium EDTA was used and samples were obtained from the cannula at the origin of the right ventral colon. Based on four determinations, the liquid flow from the caecum was 54.2 +/- 1.89 litres d-1. In the other two ponies with cannulas in the origin of the right ventral colon and near the end of the right dorsal colon, a continuous infusion of chromium EDTA was made into the right ventral colon and samples were obtained from the right dorsal colon. The flow rate towards the end of the dorsal colon was 49.4 +/- 1.25 litres d-1, based on four determinations. The capacities of the caecum and large colon after death were 7.0 +/- 0.8 and 17.7 +/- 3.7 litres, respectively. 相似文献
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本文应用Ｆｏｒｔａｎａ—Ｍａｓｓｏｎ嗜银颗粒染色法研究了貉、蓝狐、银狐的胃及十二指肠内嗜银细胞的形态分布。结果表明：三种动物胃幽门腺中，嗜根细胞数量最多，呈锥状，嗜银颗粒较粗，密度大、染成深黑色。在胃底及胃贲门腺区、嗜银细胞数量少。在十二指肠部嗜银细胞呈蝌蚪形，嗜银颗粒细，呈黑褐色，密度较小。嗜银细胞的分布密度在三种动物中具有一定的差别。 相似文献
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L R Whalen T L Spurgeon R E Carsten D H Gould 《American journal of veterinary research》1986,47(5):1063-1070
The maximal conduction velocities of compound-action potentials in the proximal and distal parts of the saphenous nerve were determined by averaging potentials evoked and recorded through needle electrodes. Antidromic, triphasic compound-action potentials unipolarly recorded from the distal part of the saphenous nerve were of the same minimal latency as potentials having 4 phases which were recorded bipolarly from the same site. However, the unipolarly recorded potentials were of greater amplitude. Monophasic compound-action potentials were recorded through bipolar chlorided silver electrodes from the surface of fascicles of the distal part of the saphenous nerve. The maximal conduction velocity of these potentials was in agreement with the conduction velocity of compound-action potentials of the distal part of the saphenous nerve which were evoked and recorded through subcutaneous needle electrodes. The specificities of the stimulating and recording sites were verified by recording before and after the saphenous nerve was cut between the stimulating and recording sites. Mean conduction velocities were 62.3 +/- 2.0 m/s for the distal part of the saphenous nerve and 66.3 +/- 2.2 m/s for the proximal part of the saphenous nerve. Reflex-evoked muscle activity was elicited in the ipsilateral tensor muscle of the fascia lata and semimembranous muscle after electrical stimulation of the saphenous nerve through subcutaneous needle electrodes. The effects of various stimulus intensities on the latency and duration of these reflex-evoked muscle potentials were determined. 相似文献
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