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1.
根据GenBank中普通牛生长分化因子9(GDF-9)基因序列(AF 307092)设计1对引物,以麦洼牦牛卵母细胞总RNA为模板,通过RT-PCR技术对牦牛GDF-9基因cDNA进行克隆测序和序列分析.结果表明:所克隆的1399 bp片段为预期的牦牛GDF-9基因cDNA序列,包含由2个外显子组成的全编码区和3′-下游部分序列.牦牛GDF-9基因编码区核苷酸序列长度为1362 bp,编码453个氨基酸,与GenBank中报道的普通牛、水牛、绵羊、山羊相应序列一致,而与人和黑猩猩存在差异.和普通牛相比,牦牛GDF-9基因编码区存在1处碱基转换(C→T),导致相应的氨基酸由丙氨酸(A)转换为缬氨酸(V).牦牛与普通牛、水牛、绵羊、山羊、人和黑猩猩的核苷酸同源性分别为99.9%、98.4%、97.0%、96.8%、85.6%和85.1%;氨基酸同源性分别为99.8%、97.1%、95.1%、95.4%、79.4%和79.5%.利用NJ法和MP法以该基因编码区核苷酸序列构建的物种间分子系统进化树结果基本一致,即牦牛与普通牛先聚为一类,再与水牛聚为一类,而后与绵羊和山羊聚为一类,最后与人和黑猩猩聚为一类.该聚类结果与物种间遗传距离大小一致,也与各物种在动物学上的分类相吻合,表明GDF-9基因编码区适用于构建物种间系统进化树.  相似文献   

2.
本研究根据普通牛的κ-酪蛋白基因设计一对引物,首次成功扩增出了水牛的κ-酪蛋白外显子4基因,并经序列分析,结果表明κ-酪蛋白外显子4基因片段长780 bp。利用GenBank上的Blast进行比较,中国水牛κ-酪蛋白外显子4序列与地中海水牛、牛、牦牛的κ-酪蛋白外显子4序列同源性分别为99.5%、96.4%、95.9%;氨基酸同源性比较,中国水牛、地中海水牛、牛、牦牛均编码260个氨基酸,中国水牛与地中海水牛、牛、牦牛同源性分别为98.9%、92.0%和91.2%。核苷酸和氨基酸序列同源性结果显示,中国水牛和地中海水牛κ-酪蛋白基因变异不大。但由于在碱基230 bp处发生了一个碱基(A→C)的变化,从而导致其氨基酸也发生了变化,即K(Lys赖氨酸)→R(Arg精氨酸)。本研究为进一步对该基因的功能奠定基础。  相似文献   

3.
对雷琼瘤牛18个个体生长激素(GH)基因外显子序列654bp进行分析,发现3个变异位点,定义了5种单倍型;引用巴州牦牛2个个体GH基因同源区序列并结合GenBank中牛属普通牛、其他瘤牛和牦牛3个种群与水牛1个远缘种GH基因外显子序列,分别采用邻接(NJ)法和最大简约(MP)法构建分子系统发育树,得到基本一致的拓扑结构。结果显示,GH基因的分化早于雷琼瘤牛、其他瘤牛、普通牛、牦牛和水牛的分化,瘤牛物种内存在多型现象,GH基因外显子区有着较高的突变率。  相似文献   

4.
对大额牛HSL基因外显子Ⅰ部分序列进行PCR扩增、测序及氨基酸预测,并同其它牛种的资料进行了比对分析,构建了分子系统进化树。结果表明:大额牛其核苷酸序列与牦牛、普通牛、瘤牛、水牛间的同源性分别为99.6%、99.4%、99.2%、97.0%。相应的氨基酸序列大额牛与水牛的同源性为97.6%;与普通牛、瘤牛、牦牛的同源性均为99.4%,仅在第33位有1个氨基酸变异,即大额牛为异亮氨酸,而其它3个牛种均为缬氨酸,这是由该基因片段的第97位碱基发生转换(A←→G)造成的。从分子系统进化树看,瘤牛和普通牛先聚为一类,再依次与牦牛、大额牛、水牛相聚,这与传统的牛种分类结果一致。  相似文献   

5.
牦牛生长激素基因cDNA分子克隆及进化分析   总被引：1，自引：0，他引：1  
根据GenBank中登录的牛、山羊和绵羊等动物的生长激素基因序列的比对结果,设计特异性引物,分别从甘南黑牦牛和天祝白牦牛脑垂体中提取RNA,采用RT-PCR技术克隆,测序获得707 bp的片段。结果表明:该片段包含牦牛生长激素基因完整的开放阅读框,长654 bp,编码217个氨基酸。与牛的核苷酸序列相比,牦牛第607位碱基为A,而牛为C,但这一碱基差异并未导致氨基酸残基的变化,均编码精氨酸。牦牛生长激素基因编码区序列与牛、山羊、绵羊、马、猪、猫和犬的同源性分别为99.8%、98.6%、97.7%、90.6%、90.1%、89.1%和88.9%,氨基酸序列同源性分别为100%、99.1%、98.6%、88.9%、88.5%、88.9%和89.4%,表明生长激素基因在进化上非常保守。基于CDS序列和氨基酸序列建立的系统进化树结果一致,且与比较形态学和比较生理学分类结果一致。  相似文献   

6.
试验旨在克隆获得水牛脂素1（LPIN1）基因，并对其进行生物信息学分析，为揭示该基因在水牛脂肪沉积、生殖发育和泌乳调控中的作用奠定基础。本研究以水牛卵巢组织cDNA为模板，PCR扩增获得了LPIN1基因CDS区全长后测序，并结合生物信息学分析方法预测及分析蛋白质理化性质、二级结构及三级结构等。结果表明，水牛LPIN1基因编码区长2 793 bp，编码930个氨基酸。MegAlign软件分析显示，水牛LPIN1基因核苷酸序列与水牛（预测）、牦牛、黄牛、山羊、藏羚羊、绵羊、猪、骆驼、人和小鼠LPIN1基因的同源性分别为99.6%、97.9%、97.7%、97.5%、97.4%、97.1%、89.9%、89.8%、86.2%和83.5%；水牛lipin1蛋白氨基酸序列与黄牛、牦牛、山羊、藏羚羊、骆驼、猪及人的同源性分别为99%、99%、99%、99%、94%、94%及90%。应用Mega 5.0软件构建系统进化树发现，水牛与黄牛的亲缘关系最近，其次为绵羊和山羊，LPIN1基因在不同物种及进化的过程中具有高度保守性。对lipin1蛋白分析发现，其二级结构由α-螺旋、β-折叠、T-转角和无规则卷曲组成；蛋白呈弱酸性，无信号肽，亚细胞主要定位于细胞核中，存在Lipin_N、LNS2和AF1Q等结构域，其中Lipin_N、LNS2为保守结构域。  相似文献   

7.
【目的】对水牛肿瘤坏死因子(tumor necrosis factor,TNF)相关凋亡诱导配体(TNF-related apotosis-inducing ligand,TRAIL)基因CDS序列进行克隆及序列分析,并对其编码的蛋白进行生物信息学分析,为后期TRAIL蛋白调控水牛卵巢卵泡发育、颗粒细胞增殖及凋亡的研究奠定基础。【方法】利用RT-PCR方法克隆水牛TRAIL基因CDS序列,对所获序列进行核苷酸序列、氨基酸序列相似性比对,构建系统进化树,并通过生物信息学软件分析TRAIL基因编码蛋白的结构和功能。【结果】试验成功克隆水牛TRAIL基因CDS序列,长864 bp,编码287个氨基酸;水牛TRAIL基因与牦牛、普通牛、山羊、绵羊、野猪、马、人、黑猩猩和家鼠的核苷酸序列相似性分别为99.2%、99.3%、95.9%、96.3%、84.7%、84.8%、81.3%、81.3%和70.0%。系统进化树结果表明,水牛与牦牛、普通牛的亲缘关系最近,与家鼠亲缘关系最远。氨基酸序列比对结果表明,在不同物种间,其跨膜结构域和TNF结构域序列保守性较高。TRAIL蛋白属于亲水性蛋白,存在1个跨膜结构域,140―285位氨基酸处为TNF区,具有29个磷酸化位点,无信号肽和糖基化位点,主要定位于细胞质中。TRAIL蛋白二级结构主要以无规则卷曲为主,约占51.57%,其次为延伸链(24.39%)和α-螺旋(24.04%)。TRAIL蛋白三级结构与二级结构一致,且与模型蛋白人TRAIL蛋白的相似性为75.53%。【结论】本试验克隆得到水牛TRAIL基因CDS区序列,大小为864 bp,编码287个氨基酸,水牛与牦牛、普通牛亲缘关系最近,TRAIL蛋白跨膜结构域和TNF结构域在不同物种间序列保守性较高,这可能与其功能有关。  相似文献   

8.
为了初步探讨牦牛RGS2基因的结构和功能,试验采用RT-PCR方法及TA克隆法得到麦洼牦牛RGS2基因,并运用不同的生物信息学软件对序列进行分析。结果表明:牦牛RGS2基因系列含1个540 bp的开放阅读框,共编码178个氨基酸,Gen Bank数据库中登录号为FJ786041。编码Phe的密码子UUU、编码Leu的密码子UUG、编码Ile的密码子AUU等20种密码子为该基因的偏好性密码子,确定的27种最优密码子均以G或C结尾。RGS2氨基酸序列与普通牛、绵羊、山羊相似性分别为99.5%、96.3%、96.1%。系统发育树上,牦牛与普通牛聚在一起,亲缘关系最近。  相似文献   

9.
试验根据GenBank登录的牛2,4-双烯-CoA还原酶1(2,4-dienoyl-CoA reductasel,DECR1)基因序列(NP_001068891)设计引物,应用PCR技术对德国美利奴绵羊、杜泊绵羊、特克塞尔绵羊DECR1基因的exon 5部分序列进行克隆测序;利用PCR-SSCP技术检测了3个绵羊群体exon 5单链构象多态性(SNP),所获序列与GenBank中其他物种exon 5序列进行了同源性比较,并构建了亲缘关系聚类分析图.结果表明,绵羊DECR1基因exon 5长为137 bp,3个绵羊群体中exon 5均不存在SNPs,各种动物之间DECR1基因exon 5的同源性较高,在81.02%(鸡)～97.08%(牛)之间,其中绵羊和牛同源性最高,达到97.08%;与鸡的同源性最低,为81.02%;聚类分析结果显示,绵羊首先与牛聚为一类,再分别与兔子、狗聚为一类,最后分别与人、猪聚为一类,绵羊与牛的亲缘关系最近,与鸡的亲缘关系最远,与传统分类相一致,说明DECR1基因exon 5在动物进化过程中高度保守.  相似文献   

10.
中国牛亚科家畜GH基因编码区序列的遗传变异研究   总被引：2，自引：0，他引：2  
采用PCR产物直接双向测序法,分段扩增普通牛、瘤牛、牦牛、大额牛和亚洲水牛共5个牛种的GH基因,并拼接成编码区全序列,分析中国牛亚科家畜不同牛种GH基因编码区序列变异及其分子进化特征。结果表明,牛GH基因编码区序列全长654bp,种间核苷酸突变率在0．1％～1．84％。5个牛种编码区序列定义了10种单倍型,瘤牛的单倍型多样性最高,大额牛和水牛均无单倍型多样性。GH基因编码区序列的密码子使用存在偏倚性,共发现了25个偏好性密码子。核苷酸的替代以转换为主,转换明显高于颠换,转换／颠换比为3．0。非同义突变位点远远少于同义突变位点,同义与非同义替代发生的速率比都小于或等于1,表明GH基因编码区序列不受达尔文正选择的影响。以GH基因单倍型序列为基础的分子进化树表明,水牛与普通牛、瘤牛、牦牛、大额牛间分化很明显;普通牛、瘤牛、牦牛、大额牛间序列分化并不明显,并且它们共同拥有一条相同的祖先核苷酸序列。说明中国牛亚科家畜GH基因编码区序列的变异相当贫乏,并且由于功能的约束表现得相当保守,进化速率相当缓慢。  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.
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   

14.
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   

15.
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   

16.
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   

17.
The purpose of this study was to determine the frequency of different tumor types within a large cohort of cats with intracranial neoplasia and to attempt to correlate signalment, tumor size and location, and survival time for each tumor. Medical records of 160 cats with confirmed intracranial neoplasia evaluated between 1985 and 2001 were reviewed. Parameters evaluated included age, sex, breed, FeLV/FIV status, clinical signs, duration of signs, number of tumors, tumor location(s), imaging results, treatment, survival times, and histopathologic diagnosis. Most of the cats were older (11.3 +/- 3.8 years). Primary tumors accounted for 70.6% of cases. Metastasis and direct extension of secondary tumors accounted for only 5.6 and 3.8% of cases, respectively. Twelve cats (7.5%) had 2 or more discrete tumors of the same type, whereas 16 cats (10.0%) had 2 different types of intracranial tumors. The most common tumor types were meningioma (n = 93, 58.1%), lymphoma (n = 23, 14.4%), pituitary tumors (n = 14, 8.8%), and gliomas (n = 12, 7.5%). The most common neurological signs were altered consciousness (n = 42, 26.2%), circling (n = 36, 22.5%), and seizures (n = 36, 22.5%). Cats without specific neurological signs were common (n = 34, 21.2%). The tumor was considered an incidental finding in 30 (18.8%) cats. In addition to expected relationships (eg, meninges and meningioma, pituitary and pituitary tumors), we found that lesion location was predictive of tumor type with diffuse cerebral or brainstem involvement predictive of lymphoma and third ventricle involvement predictive of meningioma.  相似文献   

18.
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   

19.
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   

20.
Comparison of different tests to diagnose feline infectious peritonitis   总被引：1，自引：0，他引：1  
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