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1.
采用超速离心、热变性处理、硫酸铵沉淀和亲和层析方法，从鸡肝脏中分离提纯了β－羟－β－甲戊二酸单酰辅酶Ａ（ＨＭＧ－ＣｏＡ）还原酶。提纯倍数为２０９倍，比活力１８８．５Ｕ／ｍｇ，Ｋｍ值１．８×１０－４ｍｏｌ／Ｌ。ＳＤＳ－ＰＡＧＥ测得分子量为３．２×１０４。温度对该酶活性影响较大，３７℃时活性最高。最适反应ｐＨ为７．２。甘氨酸在１０ｍｍｏｌ／Ｌ浓度以上时对该酶呈现明显抑制作用，ｌ－组氨酸、ｌ－精氨酸则无明显抑制作用。Ｚｎ２＋、Ｍｇ２＋、Ｃｕ２＋离子对该酶有明显抑制作用，Ｚｎ２＋在１．５ｍｍｏｌ／Ｌ、Ｃｕ２＋和Ｍｇ２＋在２．０ｍｍｏｌ／Ｌ浓度以上时抑制作用明显。中药山楂（ＣＨＳ）和决明子（ＣＨＺ）的水煎液对酶的抑制作用明显  相似文献   

2.
青霉素脂质体对耐药金黄色葡萄球菌的抑菌效果观察   总被引：4，自引：0，他引：4  
本实验在国内首次观察了青霉素脂质体对耐药金黄色葡萄球菌的抑菌效果及其对外源性β－内酰胺酶的耐受性。结果：青霉素脂质体对耐药菌的最低抑菌浓度（ＭＩＣ）为２４０ＩＵ／ｍｌ，最低杀菌浓度（ＭＢＣ）为２６０ＩＵ／ｍｌ，游离青霉素的ＭＩＣ为１２００ＩＵ／ｍｌ，ＭＢＣ为１６００ＩＵ／ｍｌ；空白脂质体几乎无抑菌作用。青霉素脂质体对外源性β－内酰胺酶具有很强的耐受性。结果表明，青霉素制成脂质体制剂后可大大提高其对耐药菌株的抗菌能力，原因之一是它能保护青霉素免受β－内酰胺酶的水解破坏。  相似文献   

3.
给大鼠口服甲状腺粉,每只８ｍ ｇ／ｄ,连续３０ ｄ,大鼠出现甲亢体征,检测心肌微粒体Ｎａ＋ 、Ｋ＋ －ＡＴＰａｓｅ,Ｃａ２＋ －ＡＴＰａｓｅ 和Ｍｇ２＋ －ＡＴＰａｓｅ 活性。结果：甲状腺粉组以上各项指标分别为７．６±１．３ ,１６．５±１．８和２１．８±２．２μｍ ｏｌＰｉ／ｇＨｂ ／ｈ,均明显低于丹参酮ⅡＡ 磺酸钠组和对照组（Ｐ＜ ０．０１）;丹参酮ⅡＡ 磺酸钠组和对照组比较无显著性差别（Ｐ＞０．０５）。上述结果表明,甲状腺粉诱导甲亢过程中心肌微粒体ＡＴＰａｓｅ 活性降低;丹参酮ⅡＡ 磺酸钠对ＡＴＰａｓｅ活性具有明显保护作用  相似文献   

4.
从健康桑蚕消化道来源的肠球菌（Ｅｎｔｅｒｏｃｏｃｕｓ）中发现了α、β和γ（非）溶血性的菌株都有，而且β－溶血性菌株的分离比例较高（２２．５％）。这些β－溶血性菌株只在厌氧条件下得到好的表达。在ＡＰＩ２０ＳＴＰＥＰ（Ｖ．５．０）系统中这些菌株主要是一些Ｅｎｔ．ｄｕｒａｎｃｅ菌株和不能认定菌株。  相似文献   

5.
禽霍乱基因缺陷菌株双型联合免疫的研究   总被引：2，自引：0，他引：2  
将禽源多杀性巴氏杆菌Ｃ４８－１株（血清型为５∶Ａ）用化学诱变剂亚硝基胍（ＮＴＧ）处理，从３０００多个克隆中筛选出９株链霉素依赖性基因缺陷型菌株（Ｃｓｔｄ株），经２０代连续回复突变测定，除１株外，其余８株表型稳定。将８株Ｃｓｔｄ株用小鼠做毒力比较试验，其中５株加注链霉素表现毒力，不加注链霉素则不表现毒力；用小鼠做免疫力测定，其中Ｃｓｔｄ－１和Ｃｓｔｄ－７能保护１０个最小致死量（ＭＬＤ）同型强毒菌的攻击。将Ｃｓｔｄ－１株与另一禽源多杀性巴氏杆菌Ｐ１０５９株（血清型为８∶Ａ）的链霉素依赖型菌株Ｐｓｔｄ－６混合，用小鼠做双型联合免疫试验，结果小鼠能抵抗Ｃ４８－１和Ｐ１０５９两株强毒菌混合培养物１０个ＭＬＤ的攻击，保护率达１００％。  相似文献   

6.
本文用电感耦合等离子发射光谱法（ＩＣＰ－ＡＥＳ）测定了扬子鳄主要组织和器官中的２１种无机元素：Ｋ、Ｎａ、Ｃａ、Ｍｇ、Ｐ、Ｆｅ、Ｚｎ、Ｃｕ、Ｍｎ、Ｃｒ、Ｍｏ、Ｃｏ、Ｎｉ、Ｓｒ、Ａｓ、Ａｌ、Ｂａ、Ｌｉ、Ｃｄ、Ｐｂ、Ｂｅ。为研究扬子鳄生物学及保护学提供了生物无机化学领域方面的资料。  相似文献   

7.
首次应用ＸＸＧ－Ａ型心血管功能测试仪对２９头健康成年黄牛和２８头热证黄牛部分血液动力学指标进行了无创检测和分析。与正常黄牛相比，热证组ＣＯ（Ｐ＜０．００１），ＣＩ（Ｐ＜０．００１），ＰＲ（Ｐ＜０．００１），ＶＰＥ（Ｐ＜０．０５），ＥＷＫ（Ｐ＜０．００１），ＨＯＩ（Ｐ＜０．０５），ＬＶＷＩ（Ｐ＜０．０５），ＰＰ（Ｐ＜０．００１），ＢＬＫ（Ｐ＜０．００１），ＡＣ，ＢＶ，ＭＨＲ（Ｐ＜０．００１）等指标均有不同程度的升高；而ＴＰＲ（Ｐ＞０．０５），ＭＲＴ（Ｐ＜０．００１），ＭＳＴ（Ｐ＜０．０１）都有明显的下降。结果表明，血液循环的高切变态和心血管机能兴奋是热证黄牛的重要特征。  相似文献   

8.
本研究应用５因子５水平部分实施的２次回归几乎正交旋转组合设计，采用玉米－豆粕型基础日粮和４３２只ＡＡ（ＡｒｂｏｒＡｃｒｅｓ）肉用公雏，研究日粮中锰（Ｍｎ）、锌（Ｚｎ）、钙（Ｃａ）、有效磷（ａｖ．Ｐ）、维生素Ｄ３（ＶＤ３）５因素不同添加水平的组合效应，探讨５因素与指标间的相互关系。结果表明，由二次响应面分析得出的生产函数二次曲线稳定点的预测值为３５８．７１，对应５因素组合的预测值分别为Ｃａ＝１．０１％，ａｖ．Ｐ＝０．４９％，ＶＤ３＝２１１０．７５１ＩＵ／ｋｇ，Ｍｎ＝１４１．２５ｍｇ／ｋｇ，Ｚｎ＝１７５．８５ｍｇ／ｋｇ，Ｃａ、ａｖ．Ｐ、Ｚｎ是影响生长的主因素；肉雏鸡日粮中Ｃａ、ａｖ．Ｐ、Ｍｎ、Ｚｎ、ＶＤ３任一因素的添加水平过高都会影响其它４营养素的吸收和利用；Ｍｎ－ＳＯＤ、肝锰、肾锰以及血清钙和磷、肝锌分别是反映Ｍｎ、Ｃａ、ａｖ．Ｐ、Ｚｎ营养状况的敏感指标。  相似文献   

9.
 盐胁迫是影响植物生长、发育以至产量的重要因素，试验通过对碱地风毛菊苗期分别以ＮａＣｌ和Ｎａ２ＣＯ３ 进行胁迫，Ｎａ＋ 浓度为０（ＣＫ），６０，１２０，１８０，２４０，３００，３６０ ｍｍｏｌ／Ｌ，测定其丙二醛、ＰＭ-ＡＴＰａｓｅ活性及５′-ＡＭＰａｓｅ活性，以探讨盐胁迫对其膜系统的影响及其苗期耐盐性。结果表明，盐胁迫下，碱地风毛菊丙二醛含量增大，Ｎａ２ＣＯ３胁迫下，碱地风毛菊根系和叶片中ＭＤＡ 含量在Ｎａ＋ 浓度为３６０ ｍｍｏｌ／Ｌ 时达到最大值，分别为对照的２．１５ 和１．９４倍；在ＮａＣｌ胁迫下，碱地风毛菊叶片中ＭＤＡ 含量最大为对照的１．２２倍。同一盐胁迫下，碱地风毛菊根系中ＰＭ-ＡＴＰａｓｅ活性和５′-ＡＭＰａｓｅ活性显著高于叶片（P＜０．０５），碱地风毛菊根系中ＰＭ-ＡＴＰａｓｅ活性最大为５６．２９μｇ磷酸／（ｍｇ蛋白·ｈ），而５′-ＡＭＰａｓｅ活性最大为５３．９１μｇ磷酸／（ｍｇ蛋白·ｈ）。２种盐胁迫下ＰＭ-ＡＴＰａｓｅ和５′-ＡＭＰａｓｅ活性差异显著。总之，盐胁迫下，碱地风毛菊根系比叶片受到的损害小，碱地风毛菊更耐ＮａＣｌ胁迫。  相似文献   

10.
阻断β—AR加速鸡胰岛素低血糖休克的研究   总被引：3，自引：0，他引：3  
在成年鸡上禁食４８小时后进行了阻断β－ＡＲ加速胰岛素低血糖休克的研究。试验鸡先注射心得安（１ｍｇ／ｋｇ）阻断β－ＡＲ，对照鸡先注射同剂量生理盐水。１５ｍｉｎ后均注射胰岛素（３０ＩＵ／ｋｇ，ｉｖ）。结果：对照鸡公、母各１只在５小时内出现休克；试验鸡５小时内全部出现休克，组间差异极显著（Ｐ＜０．００１）。出现休克的潜伏期对照鸡为１８３．５±１０９．６ｍｉｎ，试验鸡缩短到９０．９±３１．３ｍｉｎ（Ｐ＜０．０１）。证明阻断β－ＡＲ可显著加速鸡的胰岛素低血糖休克。  相似文献   

11.
1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.  相似文献   

12.
Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.  相似文献   

13.
Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.  相似文献   

14.
Tropical Animal Health and Production -  相似文献   

15.
The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.  相似文献   

16.
The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.  相似文献   

17.
Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.  相似文献   

18.
Comparison of different tests to diagnose feline infectious peritonitis   总被引：1，自引：0，他引：1  
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19.
An experiment was conducted to study disappearance of C14 to C18 fatty acids, lag times and biohydrogenation (BH) rates of C18 fatty acids of ground soya bean and canola seeds in situ. Three ruminally fistulated Dallagh sheep were used to determine ruminal BH of unsaturated fatty acids (UFAs). Differences in the disappearance of fatty acids through the bags and lag times were observed between the oilseeds. We saw that the longer the incubation time of the oilseeds in the rumen, the lower the content of C18:2 and C18:3. Significantly higher lag times for both C18:2 and C18:3 were observed in ground canola compared to ground soya bean. BH rates of C18:2 and C18:3 fatty acids in soya bean were three times higher than those of canola. These results suggest that the fatty acid profile of fat source can affect the BH of UFAs by rumen micro‐organisms. So that UFAs of canola had higher ability to escape from ruminal BH. It seems that fatty acid profile of ruminant products is more affected by canola seed compared to soya bean seed.  相似文献   

20.
Serum biochemical values and the wet weight to dry weight ratios of tissues were determined in yaks in Shandan county of Gansu province. The liver, kidney, heart and muscle contents of seven elements in yaks were also analysed. Most serum biochemical values were similar to those of cattle, camels and sheep, but the calcium concentration was considerably above the normal range for other ruminants. The liver contained the highest concentrations of copper, manganese and cobalt and the kidney of selenium, iron and calcium.Abbreviations Alb albumin - ALT alanine aminotransferase - AST aspartate aminotransferase - BUN blood urea nitrogen - Chol cholesterol - Glob globulin - -GT -glutamyl transpeptidase - IP inorganic phosphorus - TP total protein  相似文献   

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