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1.
实验建立了鸡胚下丘脑星形胶质细胞体外培养模型,研究了大豆黄酮对多氯联苯Aroclor 1254(A1254)引起的下丘脑星形胶质细胞损伤的缓解作用。结果表明:0.1～1μg/mL的A1254引起的细胞损伤不显著,高剂量时(10μg/mL)能引起星形胶质细胞大量死亡。抗氧化剂大豆黄酮10μg/mL能明显缓解A1254对星形胶质细胞的损伤作用。  相似文献   

2.
与传统克隆相比,手工克隆使用较为简单的仪器设备和技术操作即可生产克隆动物。小鼠作为模式实验动物在多领域得以应用。本研究中采用杂交胎鼠细胞系提供核供体细胞,在含细胞松弛素(Cytochalasin B,CB)和链蛋白酶(Pronase)及2%血清的M199 hepes缓冲液滴(CBMP)中消化透明带并切割去核,电融合后1 h,重构胚置于含Sr Cl2及CB(5μg/m L)的无钙体外培养液(Ca2+-free IVC)中激活6 h,体外培养液(IVC)中清洗3遍后,移入WOW系统培养,培养至小鼠HMC囊胚阶段。研究发现:1)CBMP液中Pronase的浓度相比20μg/m L和100μg/m L,卵母细胞透明带在10μg/m L组需要更长时间消化至消失,较有利于操作;2)直流电(DC)80 V,持续40μs,融合率达60%。3)含10 mmol/L Sr Cl2的化学激活液处理的重构胚与5mmol/L组相比,囊胚更高(29±3%∶13±3%,P0.05),差异显著;4)两种体外培养液,CZB与m PZM,在IVC囊胚率上无显著差异(29±3%∶24±5%,P0.05),而使用CZB可获得较高的囊胚率。本实验首次采用HMC方法体外条件下生产小鼠克隆胚胎,通过摸索透明带消化时间、电激活参数、化学激活试剂及培养液,尝试小鼠体外生产克隆胚胎的新方法,并取得了初步成果,技术优化及效率提高问题仍需要更进一步的研究。  相似文献   

3.
为了探究不同浓度的银杏叶复方在脂多糖(LPS)或植物血凝集素(PHA)刺激下对脾虚小鼠小肠淋巴细胞体外增殖的影响,试验用不同浓度的银杏叶复方(200μg/mL、100μg/mL、10μg/mL、1μg/mL、0.1μg/mL)同LPS或PHA刺激小肠淋巴细胞分裂增殖的方法研究对小鼠淋巴细胞体外增殖的影响。结果表明:对于脾虚小鼠小肠B淋巴细胞,以200μg/mL、100μg/mL的浓度刺激效果最佳(P0.05);相比于1μg/mL、0.1μg/mL浓度,浓度为200μg/mL时更有利于正常小鼠小肠B淋巴细胞增殖(P0.05);对于脾虚小鼠小肠T淋巴细胞,以100μg/mL浓度最佳(P0.05),浓度为200μg/mL和100μg/mL时对正常小鼠小肠T淋巴细胞的刺激增殖效果显著(P0.05)。说明银杏叶复方浓度为200μg/mL、100μg/mL时能有效刺激正常和脾虚小鼠的小肠淋巴细胞分裂增殖。  相似文献   

4.
实验旨在探究附植期热应激对小鼠胚胎发育和生殖嵴损伤的影响。将108只体重为（30±3）g的见栓0.5d(0.5dpc)孕鼠随机分配为对照组（24±1℃室温饲养）、38℃热应激组和40℃热应激组；热应激组于4.5dpc分别以38℃和40℃热应激2h/d，连续7d。记录孕鼠每日体重，于13.5dpc取小鼠胚胎，同时记录胚胎数量、胚胎重量和死亡胚胎数量，统计分析胚胎雌雄比率、含死亡胚胎的子宫比率、胚胎分布异常的子宫占比、胚胎子宫内异常分布比率；采用组织切片及透射电子显微镜观察生殖嵴组织细胞结构的变化。结果显示：与对照组相比，38℃和40℃热应激可降低孕鼠4.5～10.5 dpc和0.5～13.5 dpc体重增长率以及胚胎重量（P<0.05），同时增加胚胎子宫内分布异常比率（P<0.01）;40℃热应激可降低附植胚胎数量及增加胚胎分布异常的子宫占比（P<0.05）;38℃和40℃热应激导致生殖嵴组织细胞间隙明显增大，细胞连接方式多为桥粒连接，粗面内质网及部分线粒体肿胀，溶酶体与自噬泡增多。上述研究结果表明，附植期孕鼠遭受热应激导致胚胎发育迟缓及生殖嵴组织细胞超微结构损伤。  相似文献   

5.
为了探讨丹参水溶性成分的抗炎作用,试验选择50只小鼠分为模型对照组、阳性药物对照组、丹参水溶性成分高、中、低剂量组,阳性药物对照组腹腔注射给药,其他组灌胃给药,并制作了二甲苯致小鼠耳肿胀模型,探讨不同浓度丹参水溶性成分对小鼠耳肿胀度的影响;分离培养小鼠腹腔巨噬细胞,对丹参水溶性成分的安全性进行评价,确定最大安全浓度,然后制备脂多糖(LPS)刺激小鼠腹腔巨噬细胞炎症模型,分为药物处理组、LPS组和细胞对照组,其中药物处理组分别加入丹参水溶性成分(终浓度分别为62.5,31.3,15.6,7.8,3.9μg/mL)和LPS(终浓度2.0μg/mL),LPS组加入LPS(终浓度2.0μg/mL),细胞对照组加入RPMI 1640培养液,探讨不同浓度丹参水溶性成分对小鼠耳肿胀度、小鼠腹腔巨噬细胞吞噬中性红能力和炎性因子肿瘤坏死因子(TNF-α)、白介素(IL)-1β和IL-6水平的影响。结果表明:与模型对照组比较,丹参水溶性成分高剂量组(10 g/kg)和中剂量组(5 g/kg)对小鼠耳肿胀度有极显著的抑制作用(P0.01);与细胞对照组比较,丹参水溶性成分在浓度为62.5～2.5μg/mL时,能极显著增强小鼠腹腔巨噬细胞吞噬中性红的能力(P0.01);与LPS组比较,丹参水溶性成分在浓度为62.5μg/mL时,能显著抑制炎性因子IL-6的水平(P0.05),而对炎性因子TNF-α和IL-1β水平无显著影响(P0.05)。说明丹参水溶性成分具有抗炎作用,其抗炎机制可能与其抑制炎性因子IL-6的分泌有关。  相似文献   

6.
为了探究不同浓度的铁皮石斛对环磷酰胺(Cyclophosphamide,Cy)所致免疫抑制模型小鼠脾脏淋巴细胞体外增殖的影响,选取6周龄清洁级KM小鼠50只,体重18~22 g,全为雌性,随机分为对照组、免疫抑制组。每组各设5个重复,每个重复5只小鼠。免疫抑制组给予腹腔注射环磷酰胺(100 mg/kg·bw),对照组给予腹腔注射等量的生理盐水。1日1次,隔天注射,连续15 d。结果:铁皮石斛在终质量浓度5~135μg/mL范围内促进效果显著,其中作用48 h增殖幅度明显。对于小鼠脾脏T淋巴细胞而言,铁皮石斛浓度为20μg/mL、40μg/mL、80μg/mL均能促进免疫抑制小鼠T淋巴细胞的增殖(P0.05),尤以浓度为20μg/mL时最佳。铁皮石斛浓度为80μg/mL时对于正常小鼠脾脏T淋巴细胞分裂增殖显著(P0.05)。对于小鼠脾脏B淋巴细胞而言,铁皮石斛浓度为40μg/mL时对免疫抑制小鼠脾脏B淋巴细胞增殖效果最佳。各浓度铁皮石斛OD值均高于单纯LPS刺激,且细胞增殖情况差异显著(P0.05),但对照组中3个铁皮石斛浓度差异不显著(P0.05)。结论:铁皮石斛浓度在40μg/mL、80μg/mL时能有效协同Con A、LPS刺激小鼠脾脏T、B淋巴细胞的增殖。  相似文献   

7.
为了研究壳聚糖纳米微粒对小鼠腹腔巨噬细胞的细胞活力和一氧化氮(NO)生成的影响,探讨壳聚糖纳米微粒的免疫作用及机制。试验采用中性红吞噬试验法检测不同浓度(3.75,7.50,15.00,30.00μg/mL)的壳聚糖纳米微粒及30.00μg/mL壳聚糖对小鼠腹腔巨噬细胞细胞活力的影响,采用硝酸还原酶法测定不同浓度(3.75,7.50,15.00,30.00μg/mL)的壳聚糖纳米微粒及30μg/mL壳聚糖对小鼠腹腔巨噬细胞NO生成量的影响。结果表明:各壳聚糖纳米微粒组小鼠腹腔巨噬细胞的细胞活力与对照组和壳聚糖组相比差异均不显著(P>0.05),各壳聚糖纳米微粒组小鼠腹腔巨噬细胞NO的生成量与对照组和壳聚糖组相比差异均不显著(P>0.05)。说明壳聚糖纳米微粒的浓度对小鼠腹腔巨噬细胞的细胞活力和NO的生成量均无显著影响(P>0.05)。  相似文献   

8.
为了研究牛磺鹅去氧胆酸(TCDCA)对小鼠机体环磷酸腺苷(cAMP)和环磷酸鸟苷(cGMP)含量的影响,试验用环孢菌素A诱导特异性免疫低下模型,按相应组别对应的剂量对小鼠灌胃给药7 d,获取血清;体外培养正常小鼠腹腔巨噬细胞,用MTT方法筛选TCDCA作用于腹腔巨噬细胞的最佳药物浓度;用最佳药物浓度作用于巨噬细胞后超声破碎,获取上清液;ELISA方法测定血清和上清液中cAMP和cGMP的含量。结果表明:在TCDCA高剂量(0.2 g/kg)组小鼠血清中,cAMP含量极显著高于环孢菌素A组(P<0.01);各组小鼠血清cGMP含量差异不显著(P>0.05);TCDCA促进小鼠腹腔巨噬细胞增殖的体外浓度为1μg/mL、2.5μg/mL、5μg/mL、10μg/mL;1μg/mL、2.5μg/mL、5μg/mL的TCDCA均能显著或极显著提高细胞内cAMP含量(P<0.05或P<0.01),对cGMP含量均没有显著影响。说明TC-DCA能够显著提高正常和免疫抑制小鼠血清中和正常腹腔巨噬细胞内cAMP含量。  相似文献   

9.
吸取500μL含0.1亿个/mL鸡外周血淋巴细胞的细胞悬液,分别加入2个24孔细胞培养板的32个孔内,每4个孔为1组,共设8组:第1组为空白对照组,每孔加入500μL RPMI-1640完全培养液;第2组每孔加入500μL含10μg/mL玉米赤霉烯酮(ZEN)的培养液;第3~5组每孔分别加入500μL含0.01%、0.20%和0.30%酯化葡甘露聚糖(EGM)的培养液;第6~8组每孔分别加入500μL含0.01%、0.20%和0.30%EGM,均含10μg/mL ZEN的培养液;第2~8组ZEN质量浓度为5μg/mL;第3和6组、第4和7组及第5和8组的EGM含量分别为0.05%、0.10%和0.15%。37℃,5%CO2培养72 h后,检测培养液中白细胞介素-2(IL-2)、α干扰素(IFN-α)和丙二醛(MDA)含量,超氧化物歧化酶(SOD)活性及淋巴细胞转化率。结果表明:空白对照组、培养液中加入0.05%~0.15%EGM及培养液中加入5μg/mL ZEN和0.05%~0.15%EGM组,IL-2和IFN-α含量、SOD活性及淋巴细胞转化率均显著高于培养液中加入5μg/mL ZEN,MDA含量显著低于培养液中加入5μg/mL ZEN。培养液中加入0.10%和0.15%EGM后,IL-2和IFN-α含量显著高于空白对照组。由此表明:EGM对淋巴细胞增殖无不良影响,并能通过吸附ZEN有效地减轻ZEN对淋巴细胞的损伤。  相似文献   

10.
为研究表皮生长因子(EGF)、β-巯基乙醇(β-ME)、亚硫磺酸(HTAU)对牛卵母细胞体外成熟(IVM)及孤雌激活胚胎体外发育(IVC)效果的影响,实验采集牛卵巢采用切割法收集卵丘-卵母细胞复合体(COCs)随机处于不同浓度EGF、β-ME培养液成熟培养24 h后孤雌激活,研究其在不同胚胎培养液中的后续发育,以期筛选出最好的牛卵母细胞IVM-IVC条件。结果表明:添加25、50、100 ng/mL EGF组的成熟率、卵裂率均高于对照组,其中50 ng/mL EGF组的成熟率、卵裂率与对照组差异显著(P<0.05);50、100、500μmol/L的β-ME对牛卵母细胞体外成熟没有促进作用;50 ng/mL EGF与50、100μmol/Lβ-ME组合并无协同作用;胚胎培养基中添加不同浓度EGF对早期胚胎的体外发育无显著影响;而添加100μmol/Lβ-ME组的囊胚率、囊胚细胞数均极显著高于对照组(P<0.01);在成熟液中添加50 ng/mL EGF和100μmol/Lβ-ME、胚胎培养液中添加0.5 mmol/L HTAU孤雌胚发育最好。  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.
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   

13.
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   

14.
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   

15.
Comparison of different tests to diagnose feline infectious peritonitis   总被引：1，自引：0，他引：1  
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16.
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   

17.
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   

18.
A knowledge of the microbiological status of milk and of the different structures in the mammary glands has great importance in elucidating the pathogenesis of mammary gland infections. The objective of this study was to evaluate the microbiological status of various structures in the mammary glands from naturally infected dairy cows following slaughter. A total of 94 samples of milk, 184 samples of mammary parenchyma, 168 samples of gland cisterns, and 168 samples of teat cisterns were collected for microbiological examination. Microorganisms were detected in 59.9% of all samples, 67.0% of the milk samples, 70.1% of the mammary parenchymas, 55.9% of the gland cisterns and 48.8% of the teat cistern samples. When all samples were considered, coagulase-negative Staphylococcus were the most prevalent (35.7%) followed by coagulase-positive Staphylococcus (12.2%), Corynebacterium bovis (2.4%), Prototheca sp. (1.9%), and Streptococcus dysgalactiae (1.5%). There was a significantly higher occurrence of microorganisms in the milk and mammary parenchyma compared to the gland cisterns and teat cisterns. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

19.
Four grass plots were sequentially contaminated with goat faeces containing known numbers of unembryonated eggs of predominantly Haemonchus contortus and Trichostrongylus spp. between October 1982 and April 1983. Four other plots were similarly contaminated with sheep faeces between February and May 1987. An additional plot was repeatedly contaminated with sheep faeces from February to April 1987. Populations of free-living stages in faeces and of infective larvae (L3) in the herbage were subsequently monitored until the end of April and June of 1983 and 1987 respectively. During February and May 1987 two control cultures of sheep faeces were incubated in the laboratory at 25°C–30°C and at a constant temperature of 50°C and the free-living development was also monitored. L3 developed very readily in the faeces cultured at 25°C–30°C and in those spread on a grass plot in October, at the end of the wet season, but developed less on the plot contaminated in May at the start of the wet season. Worm eggs in faeces deposited on plots during the hot dry season (December to April) or incubated at 50°C died and disintegrated after 24–48 h exposure to the high environmental temperatures. The results indicate that it is unlikely that gastrointestinal nematodes of sheep and goats can develop or survive on open pasture during the dry season in the Nigerian derived savanna zone.  相似文献   

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