首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 36 毫秒
1.
Hyaluronidase, acrosin and N-acetylhexosaminidase activities were examined in sperm collected from 12 beagle dogs and in culture medium after 0.5 hr and 7 hr of sperm incubation. The activities of the three enzymes were significantly higher at 7 hr than at 0.5 hr (P < 0.05, 0.01), and the increases were associated with sperm capacitation. It was considered that the three enzymes in the dog sperm are related to fertilization by reason of the findings of the release of these enzymes from the sperm into the medium after 7 hr of incubation.  相似文献   

2.
试验旨在研究转基因大豆内、外源基因在少孢根霉发酵过程中的降解变化规律,并探讨其降解规律与相关酶活性的关系。试验采用定性和定量PCR检测各基因的降解变化,同时测定相关酶活。结果表明:内源基因Lectin和外源基因EPSPS在高温蒸煮下降解至800 bp以下,在发酵4 d后降解至200 bp以下;发酵过程中外源基因相对含量的变化与核酸酶、脂肪酶、蛋白酶活性的变化相一致。该研究为我国转基因食品加工过程中外源基因的降解及其机理研究提供一定的理论基础。  相似文献   

3.
The cellular and enzyme-histochemical differentiation of subcutaneous adipose tissue was studied in lean and obese pig fetuses at several ages. Positive reactions for a variety of cytosolic and organellar enzyme markers indicate metabolic competence of fetal adipocytes despite their small size (12 to 15 microns). Reactions for several enzymes decreased with fetal age and may be associated with a qualitative change in activity of adipocyte organelles. Age-associated increases in two lipogenic enzymes were observed in obese adipocytes. Observations on developing cells around hair follicles in the younger fetuses indicated significant temporal lags between the appearance of detectable enzyme activities in adipocytes. Enzyme activities in order of appearance were: dehydrogenases (cytosolic and mitochondrial), lipoprotein lipase and esterase. Esterase activity and several other enzymes were never observed in lipid positive cells that were not spherical. A proportion of hair follicle associated adipocytes in 110-d-old lean fetuses were histochemically and morphologically similar to brown adipocytes in the young rat. There was no evidence for brown adipocyte like cells in obese fetuses. Finally, comparison of the enzyme-histochemical differentiation of lean and obese fetal adipocytes indicates that fetal adipocytes become sensitive to external stimuli between 70 and 90 d of gestation.  相似文献   

4.
OBJECTIVE: To measure activities of digestive enzymes during postnatal development in dogs. SAMPLE POPULATION: Gastrointestinal tract tissues obtained from 110 Beagles ranging from neonatal to adult dogs. PROCEDURE: Pepsin and lipase activities were measured in gastric contents, and amylase, lipase, trypsin, and chymotrypsin activities were measured in small intestinal contents and pancreatic tissue. Activities of lactase, sucrase, 4 peptidases, and enteropeptidase were assayed in samples of mucosa obtained from 3 regions of the small intestine. RESULTS: Gastric pH was low at all ages. Pepsin was not detected until day 21, and activity increased between day 63 and adulthood. Activities of amylase and lipase in contents of the small intestine and pancreatic tissue were lower during suckling than after weaning. Activities of trypsin and chymotrypsin did not vary among ages for luminal contents, whereas activities associated with pancreatic tissue decreased between birth and adulthood for trypsin but increased for chymotrypsin. Lactase and gamma-glutamyltranspeptidase activities were highest at birth, whereas the activities of sucrase and the 4 peptidases increased after birth. Enteropeptidase was detected only in the proximal region of the small intestine at all ages. CONCLUSIONS AND CLINICAL RELEVANCE: Secretions in the gastrointestinal tract proximal to the duodenum, enzymes in milk, and other digestive mechanisms compensate for low luminal activities of pancreatic enzymes during the perinatal period. Postnatal changes in digestive secretions influence nutrient availability, concentrations of signaling molecules, and activity of antimicrobial compounds that inhibit pathogens. Matching sources of nutrients to digestive abilities will improve the health of dogs during development.  相似文献   

5.
为研究筛选自高寒草地5株真菌合成不同功能酶系间的互作效应,采用单个菌株发酵粗酶液直接混合和菌株组合发酵的2种方式,分别测定了反应体系中不同功能酶活力的变化情况。结果表明:菌株310b与4个菌株23a,26B,24d及H发酵粗酶液直接混合的情况下,反应体系中漆酶、羧甲基纤维素酶、木聚糖酶的酶活力下降, 且差异显著(P<0.05);而菌株310b与4个菌株组合发酵的情况下,反应体系中漆酶的酶活力下降,且差异显著(P<0.05),在与菌株23a和H的组合中,反应体系羧甲基纤维素酶和木聚糖酶的酶活力下降,且差异显著(P<0.05),与菌株26B和24d 的组合中,反应体系中羧甲基纤维素酶和木聚糖酶的酶活力没有变化。  相似文献   

6.
Biochemical changes in the small intestine during development of naturally acquired wheat-sensitive enteropathy of Irish Setters were investigated. To distinguish primary biochemical abnormalities from secondary effects of intestinal damage, progeny of affected dogs reared on a normal wheat-containing diet were compared with their own littermates reared on a cereal-free diet and with age-matched clinically normal Irish Setters fed the same wheat-containing diet. Peroral jejunal biopsy specimens were sequentially obtained between weaning and 1 year of age; specific activity and reorientating sucrose density-gradient distribution of organelle marker enzymes were determined. Major primary biochemical abnormalities were not detected in affected progeny. In affected dogs fed wheat, there was a selective, but secondary, loss of the brush border alkaline phosphatase and aminopeptidase N activities. This loss was associated with the development of partial villus atrophy, but represented a specific effect of dietary wheat on the brush border, not merely a nonspecific effect of mucosal damage, because other brush border enzymes, including disaccharidases, were not similarly affected. Increased soluble activities of lysosomal and peroxisomal marker enzymes late in the disease process may represent alterations in these 2 organelles as a secondary consequence of mucosal damage.  相似文献   

7.
添加外源性酶对猪、鸡内源消化酶活性的影响   总被引:32,自引:0,他引:32  
观察了猪、鸡不同类型饲粮中添加外源性酶制剂后对其内源性消化酶活性的影响。结果,玉米-豆粕型饲粮中添加外源酶后,37及67日龄丝毛乌骨鸡的小肠胰蛋白酶活性分别提高13.15%(P<0.05)和9.45%(P<0.05),总蛋白水解酶活性提高7.30%(P>0.05)和13.7%(P<0.05),但α-淀粉酶活性无显著变化;高麸皮饲粮中添加外源酶可使49日龄AA肉鸡的胰蛋白酶,总蛋白水解酶和α-淀粉酶活性分别提高46.50%(P<0.05),15.20%(P>0.05)和79.80%(P<0.05),而对胰脏中α-淀粉酶、脂肪酶活性无显著影响;高次粉饲粮中添加外源酶可使杜长大仔猪的小肠总蛋白水解酶活性提高21.00%(P<0.05),而对肠α-淀粉酶活性无显著影响;大麦-豆粕型饲粮中添加外源酶可使杜长大肥育猪的肠胰蛋白酶活性下降36.90%(P<0.05),肠脂肪酶活性提高72.7%(P<0.05),而对小肠α-淀粉酶和胰脏α-淀粉酶、脂肪酶活性无显著影响。据此认为,外源性酶与畜禽内源性消化酶活性的关系较为复杂,受到动物品种和饲粮类型的影响,尤其是后者。  相似文献   

8.
BACKGROUND: The clinical significance of high serum concentration or activity of markers of liver damage in cats with hyperthyroidism is unknown. OBJECTIVE: To evaluate serum markers of liver function and damage, and ultrasonographic changes in cats with hyperthyroidism and with high liver enzymes, and to determine if abnormalities resolve after treatment with 131I. ANIMALS: Nineteen cats with hyperthyroidism (15 with high serum activities of liver enzymes) and 4 age-matched healthy control cats. METHODS: Serum bile acids, albumin, ammonia, cholesterol, and blood urea nitrogen concentrations, and activities of liver-derived enzymes, and blood glucose concentrations were measured before and after 131I therapy. These values were compared with those of cats that were euthyroid. In addition, gross liver parenchymal changes detected by abdominal ultrasonographic examination, before and after 131I therapy were evaluated. RESULTS: High serum liver enzyme activities were not associated with abnormalities in hepatic parenchyma and liver functional variables, regardless of the degree of increase. Serum liver enzyme activities return to normal after control of hyperthyroidism with 131I therapy. Cats with hyperthyroidism have a significantly higher serum fasting ammonia concentration than cats who were euthyroid (P = .019). Cats with hyperthyroidism also have significantly lower serum cholesterol (P = .005) and glucose (P = .002) concentrations before compared with after 131I therapy. Nine of 19 cats with hyperthyroidism had trace ketonuria. CONCLUSIONS AND CLINICAL IMPORTANCE: These results demonstrate that extensive examination for hepatobiliary disease in most cats with hyperthyroidism is unnecessary.  相似文献   

9.
1. Two experiments were performed on broiler chicks to determine the effect of either quantitative feed restriction (QFR) from 5 to 11 d of age or meal-feeding (MF) from d 5 to 17 on development of activity of enzymes associated with protein digestion. 2. Proteolytic activity of the proventriculus was reduced by QFR but unaffected by MF. 3. General proteolytic and carboxypeptidase A activities of the pancreas were reduced by QFR and MF. 4. Amino- and dipeptidase activities of the small intestine were increased by QFR. Dipeptidase activity was unaffected by MF. 5. Nitrogen retention of QFR chicks was lower immediately following feed restriction but not in the 2 weeks following return to ad libitum access to feed. 6. Feeding regimen alters functional development of the enzymes of protein digestion and may therefore influence growth rate of broilers.  相似文献   

10.
袁庆华  桂枝  张文淑 《草业学报》2002,11(2):100-104
利用离体叶接种技术分别将伊鲁瑰斯、沙河、萨兰斯和沙湾4个苜蓉品种内的植株分为抗病株和感病株,并分别接种苜蓿假盘菌,对抗、感病植物叶片中的SOD、POD及PPO的活性进行了测定,结果表明,接种前抗、感株叶片中4种酶的活性基本相同,接种后17d内酶活性先升后降,而抗病株的酶活性增加高于感病株。最后抗、感病株3种酶活性趋于一致。  相似文献   

11.
Activities of enzymes related to energy metabolism and isoenzyme patterns of lactate dehydrogenase (LDH) were determined in peripheral leukocytes and livers of Holstein dairy cows and Institute of Cancer Research (ICR) mice. In dairy cow liver, activities of enzymes in glycolysis, malate–aspartate shuttle and lipogenesis were lower, but activities of glucose-6-phosphatase in gluconeogenesis were higher than those in mouse liver. Glucokinase activities were below detection limit in leukocytes and liver of the cows. Dairy cow leukocytes and liver showed the isoenzyme patterns with dominance of LDH-1, -2 and-3, whereas mouse leukocytes and liver showedthat LDH-5 was dominant. The LDH isoenzyme patterns were very similar between leukocytes and liver in each animal species. Some enzymes in leukocytes may reflect those enzymes activities in liver and be a useful indicator for energy metabolism in animals.  相似文献   

12.
Maturational development of drug-metabolizing enzymes in dogs   总被引:1,自引:0,他引:1  
A qualitative and quantitative assessment was made of the development of hepatic drug-metabolizing enzymes (DME) in dogs as part of a study of the ability of animal test species to metabolize drugs. The following DME variables were measured in this study: amount of cytochromes P-450 and b5; activity of the NADPH and NADH-dependent reductases associated with each of these cytochromes; activity of cytochrome P-450-mediated enzymes, including aniline and coumarin hydroxylases, aminopyrine N-demethylase, and 7-ethoxycoumarin O-deethylase; activity of a uridine diphosphoglucuronic acid glucuronyl transferase with 4-methylumbelliferone as substrate; and glutathione-S-transferase activities, with dinitrochlorobenzene and dichloronitrobenzene as substrates. Most enzyme components had achieved maximal amount or activity by the fifth to eighth week after birth; they tended to decrease after weaning, although the activity of dichloronitrobenzene-glutathione transferase in geriatric dogs (312 to 525 weeks old) was approximately twofold greater than that of 8-week-old pups. There were no gender-related differences in any of the enzyme amounts or activities determined. Individual variation was pronounced even in the homogeneous colony from which these dogs were obtained.  相似文献   

13.
14.
ABSTRACT

1. The purpose of this study was to investigate ATP levels and the activities of important enzymes involved in glycolysis and TCA cycle in livers of embryonated chicken eggs infected by infectious bursal disease virus (IBDV).

2. Embryonated chicken eggs (9 days) were randomly divided into two groups (50 eggs per group). The first group was inoculated with a very virulent IBDV (vvIBDV) isolate into the chorioallantoic membrane. The second group was maintained as uninfected control eggs and inoculated with physiological saline. Embryo survival was assessed daily, and six embryos were sacrificed at 24, 48, 72, 96, and 120 hpi for examining livers. Viral loads in the livers were evaluated by qRT-PCR. A comparative analysis of markers associated with the regulation of energy metabolism across several functional classes (ATP, pyruvic and lactic acids, mitochondrial protein, NAD+/NADH ratios, and enolase, lactic acid dehydrogenase and the respiratory chain complex I activities) were examined in the context of IBDV infection.

3. The results indicated that increases in the enzymatic activities associated with glycolytic metabolism in turn affected the synthesis and cytoplasmic concentrations of ATP at early timepoints in infected chicken embryos. Subsequently, energy metabolism was inhibited through the pathological perturbations of metabolic enzymes and mitochondrial damage, as inferred from reduced ATP generation.

4. These results suggested impaired bioenergetics, which may lead to liver dysfunction consequent to IBDV infection, contributing to the disease pathogenesis.  相似文献   

15.
Plasma metabolite concentrations and activities of enzymes related to energy metabolism in plasma, peripheral leukocytes and liver of pregnant Romney ewes with restricted feeding were measured to assess those metabolites and enzymes as indicators for evaluating metabolic conditions in the ewes. The body weights and plasma lactate concentrations of the low-feeding ewes (about 1.0 times maintenance) were significantly lower than those of the high-feeding ewes (about 1.5 times maintenance). There were no significant differences in plasma protein, glucose, triglyceride, cholesterol, pyruvate and immunoreactive insulin concentrations and plasma and leukocyte enzyme activities between both groups. Hepatic malate dehydrogenase activities were significantly higher and hexokinase activities were significantly lower in the low-feeding ewes than in the high-feeding ewes. Restricted feeding could maintain pregnancy and some plasma metabolites and peripheral leukocyte enzymes may be useful indicators for evaluating metabolic changes in ewes.  相似文献   

16.
Concentrations of plasma glucose, immunoreactive insulin (IRI) and free fatty acid (FFA) and activities of enzymes related to energy metabolism and lactate dehydrogenase (LDH) isoenzyme pattern in plasma and leukocytes were investigated in lactating Holstein cows (dairy cattle) and fattening Japanese Black Wagyu x Holstein steers (beef cattle). IRI concentrations and LDH and malate dehydrogenase (MDH) activities in the plasma of beef cattle were significantly higher than those in dairy cattle. The cytosolic ratio of MDH/LDH activity in the leukocytes of beef cattle was significantly higher than that of dairy cattle. These findings might be associated with the different energy metabolism between dairy and beef cattle.  相似文献   

17.
The principal clinical signs in 59 milk-fed calves with chronic indigestion were general malaise and depression, poor appetite, poor body condition, dehydration, a dull and scaly hair coat, alopecia and clay-like faeces. All the calves had metabolic acidosis, which was associated with an inability to stand up in more than half of them. There were significant differences in the severity of acidosis between the calves that could stand and those that could not. Other signs in some of the calves were dehydration, leucocytosis, and increased activities of liver enzymes.  相似文献   

18.
This study was designed to investigate the effects of dietary lipid levels on growth performance, lipid deposition and activities of lipid metabolic enzymes in hybrid tilapia (Oreochromis niloticus × O. aureus). Four isonitrogenous (300 g/kg crude protein) experimental diets containing graded levels of lipid (25, 55, 85 and 115 g/kg) were randomly assigned to triplicate groups of 180 juvenile fish. Fish were fed twice daily for 8 weeks. At the end of the experiment, the growth performance and proximate composition of fish were determined. The activities and gene expression of lipoprotein lipase (LPL) and hormone-sensitive lipase (HSL) were assessed as well. Fish fed the diets with 55 and 85 g/kg lipid had a significantly (p < 0.05) higher body weight gain than those fed the diets with 25 and 115 g/kg lipid. The whole-body and liver lipid contents were significantly (p < 0.05) elevated with increasing dietary lipid levels. Moreover, the activities and mRNA abundances of LPL and HSL in the liver, dorsal muscle and fat tissues were markedly altered by dietary lipid levels. Our data demonstrate a profound influence of dietary lipid levels on the growth and lipid deposition in hybrid tilapia, which is likely associated with the regulation of lipid metabolic enzymes including LPL and HSL.  相似文献   

19.
热应激降低肉鸡小肠消化酶活性的研究   总被引:23,自引:1,他引:22  
以艾维茵肉鸡为实验对象 ,研究了热应激对肉鸡消化酶活性的影响。结果显示 ,在热应激条件下 ,肉鸡小肠内总蛋白水解酶活性、脂肪酶活性和淀粉酶活性均显著下降。平均日增重与消化酶活性呈极显著正相关。表明消化酶活性下降是应激导致生产性能下降的重要原因  相似文献   

20.
Inhibitory effects of dichlorvos (2,2-dichlorovinyl dimethyl phosphate, DDVP) [corrected] on erythrocyte acetylcholinesterase (AChE) and plasma cholinesterase (ChE) activities of steers were characterized after treatments in vitro and in vivo (cutaneous application). The rates of in vitro inhibition were markedly influenced by DDVP concentration and incubation time. The activities of inhibited enzymes failed to reactivate spontaneously and had little response to treatment with 2-pyridine aldoxime methiodide (2-PAM). After gel-filtration chromatography, however, the inhibited enzymes had remarkable spontaneous reactivation and reactivation by 2-PAM treatment, indicating interference of excess unreacted DDVP in the reactivation process. Repeated cutaneous applications of a DDVP-containing livestock spray caused marked and characteristic decreases of AChE and ChE activities in blood of treated steers; however, the effects were transient because activities of both enzymes regenerated gradually. The nature of these in vivo trends suggests that spontaneous and de novo synthetic mechanisms could be responsible for complete recovery of both enzyme activities.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号