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1.
小鼠皮肤成纤维细胞的体细胞核移植   总被引：1，自引：1，他引：0  
取成年小鼠唇部皮肤进行培养，分离成纤维细胞并血清饥饿培养1周，用作核供体。对成年小鼠进行超排，取卵母细胞用作核受体，核移植重构胚经SrCl2激活处理6h后，同mM16培养液和小鼠输卵管上皮细胞共培养，把发育到早期囊胚的重构胚转移至小鼠胎儿成纤维细胞饲养层上，添加ES细胞条件培养液，消化分离ICM，然后接种培养，对孵出的ES细胞样集落进行鉴定培养。结果显示，小鼠唇部皮肤成纤维细胞为核供体，核移植重构胚2-细胞率为54．05％，桑椹胚率17．14％，囊胚率6．90％，对照组卵丘细胞的核移植重构胚2-细胞率为60．00％，桑椹胚率21．85％，囊胚率11．69％，但2种供体细胞在支持核移植重构胚发育能力上差异不显著。成纤维细胞重构囊胚中6个囊胚分离出ES细胞样集落，3个ES细胞样集落可稳定传代；对照组卵丘细胞重构囊胚中9个囊胚中分离出ES细胞样集落，5个ES细胞样集落可稳定传代。从核移植重构胚中分离出的ES细胞样集落具有岛状或巢状群体生长形态，生长旺盛的集落可自发分化成单个散在或片状存在的上皮样或梭形细胞，碱性磷酸酶检测为阳性，常规冻存复苏，仍显示ES细胞特征。  相似文献   

2.
利用PCR技术克隆了人类α-actin基因的启动子（约450bp），尝试用去掉启动子的pEGFP—N1作为框架结构，成功构建了真核表达载体pEGFP-N1-α-actin—P。应用Lipofectamine 2000将所构建的pEGFP-N1-α-actin-P转染入小鼠ES细胞。通过比较，发现在本实验室条件下，质粒DNA浓度以3．0～5．0μg／mL，转染时间约在2～3h最佳。200μg／mL的G418较适宜于靶细胞的转染与筛选。得到表达心肌a—actin和GFP的小鼠ES细胞，基本维持小鼠ES细胞的形态。PCNA染色结果表明，转染后的小鼠ES细胞具有增殖能力。α—actin抗体免疫组化染色结果表明，转染后细胞表达α-actin和GFP，揭示构建的真核表达载体pEGFP-N1-α-actin-P转染小鼠ES细胞，可能促进其向心肌细胞分化并对其筛选。  相似文献   

3.
自我更新、全能的胚胎干(ES)细胞可为移植提供几乎无限的供体来源。现已设计了一种可以在体外生成来自ES细胞的少突胶质细胞和星形胶质细胞前体,在人髓鞘质病的大鼠模型上进行的移植表明ES细胞源的前体同宿主神经元相互作用,在大脑和脊髓轴突作用更为明显。因此,ES细胞可为神经移植提供一种有价值的特异性体细胞前体的来源。源于囊胚阶段的内细胞群的ES细胞是全能干细胞,它们能分化为所有组织和细胞类型。最近的发现扩展了ES细胞的潜在作用,包括从人胚胎组织中分离出ES细胞,在绵羊和小鼠成体组织中将细胞核移入去核卵细胞,可产生同一…  相似文献   

4.
对昆明小鼠和BALB／c小鼠2种胚胎的研究表明，2种品系小鼠胚胎均可用作胚胎干细胞（ES）分离建系的材料，两者在ES分离、传代上无显著差异（P〉0．05）；大鼠心肌细胞条件培养液与添加LIF的ES常规培养液相比，显著提高了小鼠ES细胞F1、F2出现率（P〈0．05）；采用低浓度消化液使形成ES克隆的比率分别从14％、16％提高到35％、32％，使ES传到第5代的比率分别从1．7％、0提高到5％、7．1％；而采用连续消化法使形成ES克隆的比率从15％、17％提高到40％、50％，使ES传到第5代的比率从0、1％提高到10％、20％；对ES进行伊红染色、核型分析、AKP染色及体外分化能力检测，证实所分离的ES符合小鼠ES的一系列特征。  相似文献   

5.
胚胎干细胞（Embryonic stem cell,ES细胞）是从早期哺乳类动物胚胎或原始生殖细胞分离的具有全能性的细胞系。在体外分化抑制培养条件下,具有保持未分化的状态及无限增殖的能力。自Evans和Kaufman首次建立小鼠ES细胞系以来,各种动物ES细胞分离与克隆成为国际生物科学领域的热点课题之一。ES细胞可广泛应用于嵌合体的制备和克隆动物的生产。利用ES细胞遗传操作,可生产转基因动物,进行细胞基因结构与功能的关系以及细胞分化机制的研究。本研究采用不同培养方式对昆明小鼠类ES细胞进行分离及培养,供相关研究者参考。  相似文献   

6.
由体外受精囊胚获得ICR小鼠ES细胞   总被引：2，自引：0，他引：2  
收集鼠卵母细胞和精子，采用体外受精技术，获得早期胚胎。体外培养胚胎至囊胚，分离内细胞团，获得ICR小鼠的ES细胞。结果不但获得了来自体外受精囊胚的ICR小鼠ES细胞，而且表明用体外受精方法获得的小鼠早期胚胎的数量明显大于常规方法，且比较稳定。ICR小鼠ES细胞的获得，为研究小鼠的ES细胞分化提供了条件。  相似文献   

7.
为了探讨改进的小鼠表面张力辅助去核法（STA）的可靠性，本试验用改进的表面张力辅助去核法与表面张力辅助去核法对小鼠卵母细胞进行去核操作，比较其去核操作效率。结果发现，改进的表面张力辅助去核法能显著减少去核操作时间，去核率与表面张力去核法无显著差异。改进的小鼠表面张力辅助去核法是一种适用于小鼠卵母细胞操作的快速、简单、实用的去核方法。  相似文献   

8.
本研究以无血清培养基为基础培养液,旨在探求小鼠ES细胞条件培养液(ESCCM)和2种不同饲养层对绵羊类ES细胞分离、克隆效率的影响.绵羊内细胞团从胚胎中分离得到后,分别以小鼠胎儿成纤维细胞(MEF)和绵羊胎儿成纤维细胞(SEF)为饲养层进行培养.结果在MEF饲养层上,绵羊类ES细胞在ESCCM新培养系统中可稳定传至第10代,而使用基础培养液最多传至5代.而在SEF饲养层上,绵羊类ES细胞在ESCCM新培养系统中仅能传至3代.表明使用ESCCM和MEF能促进绵羊类ES细胞的分离和克隆.对类ES细胞进行核型分析、AKP染色及体外分化能力检测,证实所分离的类ES细胞符合ES细胞的主要特征,而且发现这些类ES细胞可以表达胚胎干细胞关键转录因子Nanog.结果表明,ESCCM可显著提高绵羊类ES细胞的分离克隆效率,原因可能是小鼠ES细胞在生长过程中可能分泌某些重要的细胞因子,从而达到促进绵羊ES细胞增殖的作用.且MEF比SEF更适合于绵羊类ES细胞的分离和传代.  相似文献   

9.
某些因素对牛和小鼠类胚胎干细胞分离与培养的影响   总被引：4，自引：0，他引：4  
以荷斯坦牛胚胎和小鼠胚胎为材料 ,研究了犊牛血清、饲养层、培养液、添加物和消化液对牛胚胎干细胞和小鼠胚胎干细胞克隆效率的影响。结果表明 ,在 2 4h内使小鼠胚胎贴壁率达 86 %以上的犊牛血清可用于小鼠和牛胚胎干细胞的分离 ;在 ES细胞分离与克隆中 ,以 15 %～ 2 0 %犊牛血清为宜 ,在 DMEM(L)培养基中添加 0 .1μmol/LNa2 Se O3 0 .1mmol/Lβ-巯基乙醇 10 μg/L IGF 10 0 0 IU/m L L IF,能显著提高牛 ES细胞分离与克隆效率 ;在TCM199、DMEM(高糖 )和 DMEM(低糖 ) 3种培养基中 ,低糖 DMEM更适宜于牛 ES细胞的分离 ;优秀胚胎形成的团状 ICM更适宜于分离与克隆 ES细胞 ,在 37℃用低浓度消化液处理 ICM或 ES细胞集落 ,再以机械将其离散为细胞小块 ,ES细胞克隆效率最高。  相似文献   

10.
山羊PGCs用于分离与克隆类ES细胞   总被引：11，自引：1，他引：10  
选择健康成年本地白山羊，自然发情，配种后44d取胎儿，以传统的原始生殖细胞（PGCs)分离与克隆的方法和PGCs与其胎儿生殖嵴周围组织细胞共同培养的方法获得类胚胎干细胞（类ES细胞），并对山羊类ES细胞在不同饲养层上进行培养。结果表明，采用传统方法与共培养的方法并添加细胞因子均能分离获得类ES细胞。分离获得的类ES细胞在同源（山羊）胎儿细胞饲养层上生长效果较好，可传4代或5代，而在小鼠原代成纤维细胞饲养层上类ES细胞仅传3代。另外，共培养不添加细胞因子组仅获1个ES细胞集落，传代后丢失。  相似文献   

11.
试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。  相似文献   

12.
Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.  相似文献   

13.
Tropical Animal Health and Production -  相似文献   

14.
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   

15.
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   

16.
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   

17.
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   

18.
Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.  相似文献   

19.
The objective of this report was to characterize 20-year changes in proportion of calcium oxalate (CaOx) calculi and struvite calculi in dogs, and associations with breed, age, and sex. In this retrospective study, results of analysis of urinary calculi from dogs were reviewed for specimens received between July 1, 1981, and December 31, 2001. Breed, sex, age, year of submission of the specimen, and mineral type(s) were analyzed statistically. CaOx or Struvite or both were contained in 18,966 of 20,884 (91%) specimens. For both sexes, a 20-year statistically significant increase was observed in the proportion of calculus specimens that contained CaOx. The increase in this proportion was greater in females (1% to 31%) than in males (18% to 82%). From 1998 to 2001, when proportions may have plateaued, the odds of specimens containing CaOx were markedly higher in 18 breeds, markedly lower in 5 breeds, and not significantly different in 13 breeds compared with crossbreds. For both sexes, a 20-year statistically significant decrease was observed in the proportion of calculus specimens that contained struvite. This decrease in proportion was greater for males (79-16%) than for females (97-68%). From 1998 to 2001, when proportions plateaued, the odds of calculi containing struvite were markedly lower in 20 breeds, markedly higher in 1 breed, and not significantly different in 15 breeds when compared with crossbreds. Breed, age, and sex were associated statistically with CaOx or struvite urolithiasis. In conclusion, there appears to have been a long-term increase in the proportion of specimens of canine urinary calculi that contain CaOx as well as a long-term decrease in the proportion of specimens of calculi that contain struvite for both male and female dogs. The rate of change appeared to begin leveling off in the period 1998 to 2001. The recent proportion of dogs with either CaOx- or struvite-associated urolithiasis may depend on breed, age, and sex, and on interactions among these 3 factors.  相似文献   

20.
<正>1.INTRODUCTION Ensuring transportation network security is one Of the most daunting challenges confronting homeland security agencies today.Significant research has been dedicated.To model and analyze the vulnerability of transportation systems,while notably fewer studies propose specific strategies for deploying defensive technologies to safeguard these systems.  相似文献   

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