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1.
部分金属离子及EDTA对瘦肉型猪(PIC344)精液酸性磷酸酶活性与荧光光谱的影响 总被引：1，自引：0，他引：1
研究了K+、Mg2+、Ni2+、Zn2+、Mn2+、Fe2+、Cd2+、Ca2+、Cu2+9种金属离子及EDTA对瘦肉型猪(PIC344)精液酸性磷酸酶(ACPase)活力的影响,发现K+、Mg2+、Ca2+、Ni2+、Mn2+对ACPase有不同程度的激活作用。Cu2+、Cd2+、Fe2+、Zn2+对ACPase有不同程度的抑制作用。同一浓度范围内的金属离子对ACPase的激活作用强弱依次为Mg2+>Ni2+>Mn2+>K+>Ca2+,对ACPase的抑制作用强弱依次为Cu2+>Cd2+>Fe2+>Zn2+。利用双倒数作图法研究了Cu2+、Cd2+对酶的作用,结果表明这2种抑制剂对酶的抑制作用为非竞争性抑制,用Dixon作图法求得其抑制常数Ki值分别为0.58×103mol/L、9.44×103mol/L。研究了Mg2+、Ca2+、Cd2+、Cu2+对酶荧光光谱的影响,结果表明:Mg2+、Ca2+、Cd2+、Cu2+引起酶荧光发射光谱强度降低,最大发射波长不变,说明这些金属离子对酶的构象有不同程度的影响。 相似文献
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通过电动匀浆、硫酸铵沉淀、Sephadex G-75凝胶过滤、DE-23离子交换层析和Sulfamylon-Sepharose 4 B亲和层析等方法,从蛋鸡输卵管中提纯了碳酸酐酶(CA)。提纯倍数为171倍。提纯后经聚丙烯酰胺梯度凝胶电泳鉴定其纯度,结果为1条蛋白带。测定CA分子量为29 800。该酶对热较敏感,于56℃下作用10min,其活性丧失65.5%;氨苯磺胺对CA有较强抑制作用,100μmol/L时使其活性几乎完全丧失;谷胱甘肽在0.5mmol/L时对CA有较微弱的激活作用,以后随着浓度升高则呈抑制效应;半胱氨酸对CA抑制作用较弱,50mmol/L时使其活性丧失10.14%;除Ca2+外,多种金属离子对CA均有不同程度的抑制作用,其中Cu2+、Zn2+、Ca2+、Se4+对CA抑制作用较强,Mn2+、Mg2+、Co2+、Fe3+对CA抑制作用较弱。Ca2+在10-5mol/L时可最大程度地激活CA使其IAR提高到117.7%,以后随浓度升高,激活作用逐渐减弱甚至呈抑制作用。 相似文献
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利用筛选培养基从不同豆制品作坊附近的土样中筛选出一株产α-半乳糖苷酶的菌株D-1,对其进行分子鉴定及所产的α-半乳糖苷酶进行酶学特性研究。研究表明,菌株D-1为Aspergillus niger,此菌株所产α-半乳糖苷酶的最适反应温度是55℃,在60℃以下热稳定性较好;最适反应pH值为5.0,在pH值3.0～5.5范围内稳定性较好,相对酶活>64.1%;Mg2+、Na+、Pb2+、K+、Mn2+、Co2+、Al3+对α-半乳糖苷酶均有不同程度的抑制作用,其中Cu2+和Fe3+的抑制作用较为明显,而Ca2+、EDTA(乙二胺四乙酸)、Zn2+对α-半乳糖苷酶有一定的促进作用。 相似文献
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黑曲霉FnD5-2产木聚糖酶液体发酵及酶学特性 总被引：1，自引：0，他引：1
试验旨在研究黑曲霉FnD5-2产木聚糖酶液体发酵及酶学特性。选用黑曲霉FnD5-2为出发菌株,采用单因素、正交试验设计、盐析等试验方法,开展木聚糖酶发酵条件优化及酶学性质研究工作。结果表明:最适发酵条件为28℃、pH5.0、Tween80添加量1.5 mL、脱脂豆粉添加量4 g/100mL、培养基装液量50 mL。黑曲霉木聚糖酶最适温度为50℃;最适pH为5.0;在4～50℃及pH 4～6的条件下稳定性较好;Mg2+、Fe2+、K+、Ca2+对该酶有激活作用,Co2+、Cu2+、Na+、Mn2+对该酶有抑制作用,Mn2+的抑制作用最强,蔗糖对酶液的保护效果比较好。 相似文献
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为了提高产淀粉酶枯草芽胞杆菌Bacillus subtilis N21的酶活,试验采用紫外线对该菌株进行诱变,并对该淀粉酶的部分酶学性质进行了研究。结果表明,淀粉酶酶活由出发株的32.96 U/mL增加到86.24 U/mL,比原菌株酶活提高了161.65%。该酶的最适反应温度为35℃,最适pH值为7.0,在30~40℃,pH值为5.0~8.0条件下较稳定。Ca2+和Mn2+对酶有激活作用,Cu2+、Zn2+对酶有抑制作用,而Mg2+、Fe2+对其影响较小。说明筛选出1株产酶活性较强的突变菌株。 相似文献
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米曲霉ZW-06中性蛋白酶的粗分离及酶学性质研究 总被引：2，自引：0，他引：2
从米曲霉(Aspergillus oryzae)ZW-06发酵干曲中对中性蛋白酶进行粗分离,并对其酶学性质进行研究。结果表明:用硫酸铵沉降法所得粗酶粉的酶活力高达264443U/g;该酶的最适反应温度为45℃,最适作用pH为6.5和9.0;该酶在常温及pH6～10的环境下比较稳定;Mg2+、Mn2+和Ca2+对蛋白酶有强烈的激活作用,Fe2+和Cu2+则对其表现出强烈的抑制作用。动力学研究表明,该中性蛋白酶在pH 6.5和45℃条件下,Km为3.82mg/mL,Vmax为541U/mg·min。 相似文献
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米曲霉ZW-06中性蛋白酶白粗分离及酶学性质研究 总被引：1，自引：0，他引：1
从米曲霉(Aspergillus oryzae)ZW-06发酵干曲中对中性蛋白酶进行粗分离,并对其酶学性质进行研究.结果表明用硫酸铵沉降法所得粗酶粉的酶活力高达264443 U/g;该酶的最适反应温度为45℃,最适作用pH为6.5和9.0;该酶在常温及pH 6～10的环境下比较稳定;Mg2+、Mn2+和Ca2+对蛋白酶有强烈的激活作用,Fe2+和Cu2+则对其表现出强烈的抑制作用.动力学研究表明,该中性蛋白酶在pH 6.5和45℃条件下,Km为3.82 mg/mL,Vmax为541 U/mg·min. 相似文献
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将来源于藏猪粪便的枯草芽孢杆菌BY-4菌株接种于含4%麸皮的产酶培养基中,37℃、220r/min培养48h,发酵上清液经HiTrap Phenyl HP疏水作用层析、HiPrep 16/60Sephacryl S-100凝胶过滤层析分离纯化得到一个内切葡聚糖酶组分,纯化倍数为15.5,回收率为25.0%。经SDS-PAGE、酶谱分析鉴定,两步分离纯化后为电泳纯的纤维素酶,相对分子量约为55 000。酶学性质研究表明,该酶的最适反应pH为4.5,最适反应温度为60℃。Mg2+、Zn2+对该酶有一定的激活作用,而Mn2+、Co2+、Ag+对该酶产生了抑制作用。 相似文献
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1. Plasma alkaline phosphatase (ALP) activity was determined in 4 laying strains (White Leghorn, New Hampshire, Native Brown and Native Barred) at 48 and 54 weeks of age. Birds were fed 1 of 2 isoenergetic diets with calculated crude protein contents of 152 and 181 g/kg. 2. No significant differences in plasma ALP activity were noted between the strains, although significant differences in laying performance between strains were evident. 3. There was no response in plasma ALP activity to the high dietary protein level in any strain. Depressed plasma ALP activity was associated with increasing age of birds. 4. The results failed to confirm the suggestion that ALP activity is related to egg production of the laying hen. 相似文献
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The substrate that was split most rapidly by acid phosphatase was p-nitrophenylphosphate. Two peaks of activity were obtained at pH 4.6-4.8 and 5.1-5.4. The enzyme remained stable for a long time when refrigerated. It was inhibited strongly by urea and tartrate, and slightly by fluoride and L-phenylalanine. Mercaptoethanol elicited pronounced activation of the enzyme. Four different forms of isoenzyme, giving rise to 11 phenotypes, were identified. A suitable analytical technique was electrophoresis on polyacrylamide gel with phosphate-citrate buffer. Mean activity was 3.15 +/- 0.41 units per gramme of haemoglobin haemolysate. Some of the isoenzyme preparations showed considerable variation in activity. There was no change in enzyme activity after temporary hypomagnesaemia. Acid phosphatase activity was high in testis, kidney and intestinal mucosa; myocardium, liver and spleen showed moderate activity. Five isoenzymes were demonstrable in a starch column and six in PAA gel. 相似文献
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Diagnostic value of alkaline phosphatase isoenzyme separation by affinity electrophoresis in the dog. 总被引：2，自引：0，他引：2 
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下载免费PDF全文 Affinity electrophoresis, using wheat germ lectin, was used to separate the alkaline phosphatase isoenzymes in the sera of 150 dogs with alkaline phosphatase values greater than or equal to 150 IU/L. The method provided clearer separation of the liver, bone and steroid-induced alkaline phosphatase isoenzymes commonly observed in canine serum, compared to conventional cellulose acetate electrophoresis. The dogs were divided into four patient groups determined by previous corticosteroid treatment, evidence of elevated endogenous corticosteroid levels, age and alanine aminotransferase values. The isoenzyme pattern of each patient was qualitatively assessed. The isoenzyme pattern most frequently observed was greater than 50% steroid induced alkaline phosphatase, which was present in 76 of 150 dogs. This pattern was observed in 18 of 22 dogs receiving corticosteroid therapy, two of three dogs with hyperadrenocorticism, and in dogs with a variety of other diagnoses. The majority of immature dogs (12 of 20) had an isoenzyme pattern consisting of greater than 50% bone. The majority of dogs with active hepatocellular injury (16 of 27) had greater than 50% liver isoenzyme. The isoenzyme pattern was not specific for certain diseases, therefore the diagnostic usefulness is limited. However the isoenzyme result is useful in some cases to determine which further diagnostic tests are indicated, and to determine the source of alkaline phosphatase elevation. 相似文献
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Polyacrylamide gel electrophoresis was used to characterize the isoenzymes of serum alkaline phosphatase in the rat. The electrophoresis of serum from normal rats resulted in two bands of alkaline phosphatase activity. A prominent band in serum corresponded in electrophoretic mobility to the alkaline phosphatase from bone and intestinal tissue extracts and also a slower migrating liver isoenzyme. A less prominent, fast migrating band in serum had a mobility similar to a faster migrating liver tissue extract isoenzyme. This band only represented 1-2% of the total alkaline phosphatase present in the serum of normal rats but approximately 15% of the total alkaline phosphatase in the serum of rats fed excess levels of zinc. The study also revealed an alteration in the electrophoretic mobility of alkaline phosphatase in bone homogenate by the addition of deactivated serum to the homogenate. The addition of deactivated serum did not alter the electrophoretic mobility of the liver and intestinal alkaline phosphatases in rats. 相似文献
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粗酶制剂在大麦日粮中对产蛋鸡的影响 总被引：3，自引：0，他引：3
就粗酶制剂在大麦日粮中对产蛋鸡产蛋性能的影响进行了两次试验。按０．１％比例的酶制剂添加于含大麦２８．５％和５０％的日粮中，分别饲喂３３０和２４２日龄的产蛋鸡。结果添加酶制剂对鸡产蛋率无明显提高，而对每个蛋重和鸡蛋质量有所改善，同时使产蛋鸡外周血液中促甲状腺激素和生长激素显著提高，而使甲状腺素显著降低。 相似文献
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F J Archer S M Taylor 《The Canadian veterinary journal. La revue veterinaire canadienne》1996,37(12):735-739
The effect of hyperthyroidism on serum markers for increased bone metabolism and turnover was evaluated in 36 cats with elevated serum levels of thyroxine and alkaline phosphatase. Serum was analyzed for total and ionized calcium and phosphorous. Alkaline phosphatase isoenzymes were separated by agarose gel electrophoresis and osteocalcin was measured by radioimmunoassay. Values for hyperthyroid cats were compared with those for healthy cats. Alkaline phosphatase bone isoenzyme was markedly increased in all 36 hyperthyroid cats. Osteocalcin was increased in 44% of the cats. There was no correlation among the magnitude of increase in alkaline phosphatase bone isoenzyme, osteocalcin, and serum thyroxine concentrations. Increased serum phosphorus was found in 35% of the cats. Total calcium was within the reference range in all cats, while 50% of the cats had reduced levels of serum ionized calcium. We conclude that hyperthyroid cats do have altered bone metabolism, although it is usually clinically insignificant. 相似文献
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The objective of this study was to isolate and identify a hypothetical Chlamydiaceae pathogen from laying hens with an oviduct cyst, and to characterize its potential causal relation with decreased egg production. Our clinical survey showed that cystic oviducts were prevalent at rates of 10% and 15.1% in breeder and commercial hen flocks, respectively. Chlamydial antigens were detected in 20 of 50 pharyngeal swabs (40%) and in 17 of 20 oviduct tissues (85%) using enzyme-linked immunosorbent assay (ELISA) antigen detection kits. The isolated pathogen was identified as Chlamydophila psittaci via complement fixation test, PCE-ELISA, and immunofluorescence assay. Avian influenza virus, Newcastle disease virus, and infectious bronchitis virus were excluded after oviduct tissues were inoculated onto the chorioallantoic membrane of embryonating eggs. The nucleotide sequence of the omp1 gene (accession no. EF202608) from the isolate was similar to that of C. psittaci avian type C (accession no. L25436). Typical cystic oviducts were observed in specific-pathogen-free hens inoculated intraperitoneally with the isolate. The high presence of chlamydial antigen is consistent with the cystic oviducts and poor egg production. We conclude that the isolated C psittaci is most likely associated with cystic oviducts in laying hens. 相似文献
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The effects of two lathyrogens (beta-aminopropionitrile and semicarbazide) on the reproductive system of the laying hen were compared by measuring the changes in the ovary and oviduct associated with a diminished egg production rate. The laying hens were fed diets containing either beta-aminopropionitrile, the toxic constituent of certain legume seeds in the genus Lathyrus or semicarbazide to induce lathyrogenic effects in which reduced egg production was one of the toxic effects. The gross examination of the reproductive system of the hens revealed that ovarian activity was greatly impaired. The reduced egg production after feeding beta-aminopropionitrile was due to the reduced growth rate of the ovary, and in the case of semicarbazide, to the atresia of large yolky follicles. 相似文献
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本试验旨在研究饲粮中添加甜菜碱对热应激蛋鸡生产性能、蛋品质及血清生化指标的影响。选用健康的22周龄商品代罗曼褐蛋鸡600只,随机分成5组,每组8个重复,每个重复15只鸡。Ⅰ组为正对照组,饲喂基础饲粮,正常温热环境,温湿指数(THI)介于64.9~68.9;Ⅱ组为负对照组,饲喂基础饲粮,热应激环境,THI72;Ⅲ~Ⅴ组分别在基础饲粮中添加200、400和600 mg/kg甜菜碱,均为热应激环境,THI72。试验期为14周。结果表明,各组间平均日采食量、料蛋比和破蛋率差异不显著(P0.05)。与Ⅰ组相比,Ⅱ组显著降低了入舍母鸡产蛋率、入舍母鸡产蛋重及血清总蛋白(TP)含量、碱性磷酸酶(AKP)活性(P0.05),显著提高了血清中谷草转氨酶(GOT)、肌酸激酶(CK)和谷丙转氨酶(GPT)活性(P0.05)。与Ⅱ组相比,Ⅳ组入舍母鸡产蛋率、入舍母鸡产蛋量和血清TP含量均显著提高(P0.05),Ⅴ组入舍母鸡产蛋量及血清TP、白蛋白(ALB)含量也显著提高(P0.05),而Ⅳ组和Ⅴ组的血清CK、GPT活性却显著降低(P0.05),且Ⅴ组的血清甘油三酯(TG)含量也显著降低(P0.05)。综上所述,热应激可使产蛋鸡的新陈代谢和生理机能发生变化,导致生产性能下降,而饲粮中添加甜菜碱可以提高入舍母鸡产蛋率和入舍母鸡产蛋重,并改善热应激对蛋鸡的损伤,饲粮中甜菜碱的适宜添加量为400 mg/kg。 相似文献
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Hoffmann WE Sanecki RK Dorner JL 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1988,17(3):66-70
A sensitive assay for the corticosteroid-induced alkaline phosphatase isoenzyme (CAP), adaptable to most clinical chemistry autoanalyzers, is described and validated. This assay is based on the greater than 98% inhibition of liver alkaline phosphatase isoenzyme (LAP) activity with 4.2 mM levamisole, as compared to the 42% inhibition of CAP activity. Analysis of serum with total alkaline phosphatase (AP) activity within the reference range, resulted in a reference range of 0 to 19 U/L for CAP activity. Analysis of serum from 160 clinical patients with AP activity above the reference range, revealed 73% with increased CAP activity ranging from 20 to 7,000 U/L. The diagnostic significance of this increased CAP activity is discussed. 相似文献