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1.
Pineal melatonin may play an important role in regulation of vertebrate circadian rhythms and in human affective disorders. In some mammals, such as hamsters and sheep, melatonin is involved in photoperiodic time measurement and in control of reproduction. Although wild mice (Mus domesticus) and some wild-derived inbred strains of mice have melatonin in their pineal glands, several inbred strains of laboratory mice (for example, C57BL/6J) were found not to have detectable melatonin in their pineal glands. Genetic analysis suggests that melatonin deficiency in C57BL/6J mice results from mutations in two independently segregating, autosomal recessive genes. Synthesis of melatonin from serotonin in the pineal gland requires the enzymes N-acetyltransferase (NAT) and hydroxyindole-O-methyltransferase (HIOMT). Pineal glands from C57BL/6J mice have neither NAT nor HIOMT activity. These results suggest that the two genes involved in melatonin deficiency are responsible for the absence of normal NAT and HIOMT enzyme activity. 相似文献
2.
Basal and phenobarbital-induced rates of hepatic metabolism of coumarin to 7-hydroxycoumarin are markedly higher in DBA/2J mice than they are in the AKR/J, C57BL/6J, and C3H/HeJ strains. Intermediate coumarin hydroxylase activity in F(1) hybrids of mating between DBA/2J and the other three strains indicates an additive mode of inheritance. 相似文献
3.
不同品系小鼠精子冷冻及冻融精子体外受精的研究 总被引：6，自引：1，他引：6
采用小鼠精子冷冻、冻融精子体外受精的方法,进行小鼠保种、引种、生物净化及品系标准化的可行性研究,并初步探究小鼠精子冷冻的影响因素。实验选用同一年龄5种不同品系小鼠分别进行精子冷冻、复苏,并比较各品系冷冻效果及冻融精子的体外受精(IVF)率。结果显示,冷冻后各品系小鼠精子复苏存活率约在15%～50%之间;冻融小鼠精子体外受精结果随遗传背景的不同差异显著,受精率分别为:KM小鼠68.4%、ICR小鼠30.3%、DBA/2J小鼠47.2%、C57BL/6J小鼠6.8%、BALB/cA小鼠25%。冻融精子IVF得到的胚胎可以耐受体外培养。 相似文献
4.
本文对开放式设施内饲养的7个品系中351只实验小鼠的肠道寄生虫作了观察。共检出方种寄生虫;毛滴虫、鼠贾第虫、鼠六鞭虫、隐藏管状线虫、四翼无刺线虫和微小膜壳绦虫;其感染率为:毛滴虫100%、鼠贾第虫49.57%、鼠六鞭虫22.51%、隐藏管状线虫58.40%、四翼无刺线虫21.94%、微小膜壳绦虫21.37%。 相似文献
5.
【目的】检测健康C57BL/6和A/J小鼠常规免疫指标,构建脾脏消减cDNA文库并筛选差异表达基因,以探讨两品系小鼠对猪链球菌抗病性差异的分子机制。【方法】利用ELISA法检测血清常规免疫指标,抑制性消减杂交（suppression subtraction hybridization,SSH）技术构建8周龄小鼠脾脏差异表达基因的cDNA文库。【结果】试验结果表明,A/J品系小鼠血清中IgA水平明显高于C57BL/6品系小鼠（P＜0.05）,而血清IgG和IFN水平在两品系小鼠间均无显著差异。对筛选的149个阳性克隆进行测序,去除冗余的cDNA序列载体并聚类拼接后获得56条差异表达序列标签（ESTs）。利用Genebank的BLAST分析核酸和蛋白质同源性比较,26个不同的基因或ESTs具有高度的同源性,2条ESTs未找到同源序列。【结论】筛选到很多EST与信号转导、细胞凋亡及免疫等重要功能基因高度同源,为研究猪链球菌的致病机理和防治提供了实验依据。 相似文献
6.
Singer JB Hill AE Burrage LC Olszens KR Song J Justice M O'Brien WE Conti DV Witte JS Lander ES Nadeau JH 《Science (New York, N.Y.)》2004,304(5669):445-448
Chromosome substitution strains (CSSs) have been proposed as a simple and powerful way to identify quantitative trait loci (QTLs) affecting developmental, physiological, and behavioral processes. Here, we report the construction of a complete CSS panel for a vertebrate species. The CSS panel consists of 22 mouse strains, each of which carries a single chromosome substituted from a donor strain (A/J) onto a common host background (C57BL/6J). A survey of 53 traits revealed evidence for 150 QTLs affecting serum levels of sterols and amino acids, diet-induced obesity, and anxiety. These results demonstrate that CSSs greatly facilitate the detection and identification of genes that control the wide diversity of naturally occurring phenotypic variation in the A/J and C57BL/6J inbred strains. 相似文献
7.
Adult mice [CBA/J (H-2(k))], which received either a single sublethal dose of x-radiation (500 rad) or urethan plus 500 rad, were given intravenous injections of C3H/HeJ (H-2(k)) spleen or bone marrow cells (18 to 42 x 10(6) cells per mouse) or both, for 3 days. C3H/HeJ tail-skin homografts were retained (over 130 days) by these mice, whereas BALB/cJ (H-2(d)) homografts all were rejected within 33 days. Similarly irradiated or urethan-treated controls (or controls treated with a combination of both), which did not receive C3H cells, rejected both homografts. Specific homograft tolerance is induced in adult mice by this procedure. 相似文献
8.
Marrow cells derived from C57BL/6 mice form many fewer splenic colonies in irradiated C57BL/6 x C3H F1 hybrid recipients than in irradiated C57BL/6 recipients (repression of colony formation). This effect is reversed by treatment of the hybrid recipients with active antiserum to mouse thymocytes. The repression phenomenon cannot readily be explained in immunological terms; hence the effect of the antilymphocyte serum on this phenomenon may not result from immunosuppression in the usual sense. 相似文献
9.
Susceptibility to two strains of Friend leukemia virus in mice 总被引：33，自引：0，他引：33
F Lilly 《Science (New York, N.Y.)》1967,155(761):461-462
A mutant strain of the Friend leukemia virus is described. The parental virus strain, passaged through ICR/Ha mice, shows no or very little activity by the spleen-focus assay in BALB/c mice (by comparison with highly susceptible DBA/2 and ICR/Ha mice) and produces typical Friend disease in these mice only exceptionally; susceptibility to this strain of virus is recessive in the (C57BL/6 x DBA/2) F(1). By contrast, the mutant virus strain is as active in BALB/c mice as in DBA/2 or ICR/Ha mice; susceptibility to the mutant virus strain is dominant in the (C57BL/6 x DBA/2) F(1). 相似文献
10.
Adult C57BL/6J male mice received either a primary ectopic transplant or a primary and a challenge ectopic transplant of trophoblast tissue obtained from the ectoplacental cones of 7(1/2)-day-old C3H/HeJ x C3H/HeJ embryos. Gross and histologic examinations of these grafts at 5, 7, and 12 days of growth indicated that the challenge grafts were inhibited in growth; there were a smaller percentage of grossly successful grafts, smaller hemorrhagic reactions, fewer viable cells at all stages of growth, and better host containment of the colony. The evidence indicates that exposure to pure trophoblast alters an animal's subsequent reaction to grafts syngeneic with the original trophoblast and can best be explained as evidence of immunologic sensitization of the host. 相似文献
11.
采用生物素标记的(GGAT)4寡核苷酸探针对C57BL/6J、BALB/c和DBA/2三种近交系小鼠进行了DNA指纹图分析.结果表明:(GGAT)4寡核苷酸探针对上述3种近交系小鼠产生的DNA指纹图的图带数均为10-12条,具有良好的多态性,品系内平均DNA指纹图的相似系数在0.92~1.00的范围内,具有相同指纹图的概率均在0.40以上,极显著地高于品系间的相似系数(0.21~0.39)和相同指纹图的概率(P<3.10×10-7),说明(GGAT)4寡核苷酸探针可用于制作近交系小鼠的DNA指纹图,以对其进行遗传检测. 相似文献
12.
A cytoplasmically transmitted, diet-dependent difference in response to the teratogenic effects of 6-aminonicotinamide 总被引：2，自引：0，他引：2
The frequency of congenital cleft palate produced by maternal treatment with 6-aminonicotinamide during pregnancy is lower in the C57BL/6J than in the A/J inbred mouse strain. In the C57BL/6J strain the frequency is lower when the mothers are maintained on Purina Lab Chow than when they are on Breeder Chow. A/J females do not show this effect of diet. There is a matroclinous reciprocal cross difference in frequency of induced cleft palate which persists in the back-cross when the F(1) mothers are maintained on Lab Chow but not on Breeder Chow. 相似文献
13.
[目的]探讨不同周龄、不同初始注射时间对小鼠超数排卵效果的影响。[方法]用10 IU PMSG+10 IU HCG间隔48 h处理C57BL/6J小鼠,收集并统计合子数。[结果]4周龄超排效果优于于8周龄,可达26.86枚∕只;4周龄C57BL/6J小鼠PMSG和HCG注射时间为12:00—13:00,超排后收集合子数可达30枚∕只以上,而且体外培养的发育状况良好。[结论]4周龄C57BL/6J小鼠适宜超数排卵;PMSG和HCG注射时间为12:00—13:00,超排效果相对理想。 相似文献
14.
目的观察正常小鼠各种器官组织中胸腺间质淋巴细胞生成素（thymicstromal lymphopoietin,TSLP）的表达。方法利用Real-time PCR、免疫荧光法检测正常C57BL/6J小鼠心、肝、脾、肺、肾、肠、胸腺、阴道中TSLP的表达。结果心、肝、脾、肺、肾、肠、胸腺、阴道中均有TSLP表达,其中心、肝、肾、阴道表达较高,肠道表达最低（P〈0.01）。结论 TSLP在正常C57BL/6J小鼠许多器官组织中均有表达,但以心、肝、肾、阴道黏膜中表达较高。 相似文献
15.
16.
BRUELL JH 《Science (New York, N.Y.)》1963,142(3600):1664-1666
Serum cholesterol level ( SCL) was measured in 600 mice belonging to five inbred strains of mice ( DBAIIJ, C57BL/ 1OJ, A/ J, C3H/ HeJ, and BALBI cJ) and all 20 F, hybrids resulting from the systematic crossing of the inbreds. Diet was kept constant and its effect on SCL was not evaluated. The data show that in mice, the mode of inheritance of SCL is neither dominant nor recessive, but is intermediate. A simple additive model accounts for the results: the SCL is a linear function of the SCL of the mother, the SCL of the sire, and the sex of the subject; the three factors do not interact. 相似文献
17.
E A Cornelius 《Science (New York, N.Y.)》1972,177(48):524-525
A graft-versus-host reaction induced in (SJL/J x C57BL/1)F(1) hybrid mice by injection of SJL/J spleen cells resulted in 100 percent incidence of tumors at 40 days. Transplantation studies revealed that the tumors were antigenically C57BL/1. Since both SJL/J and C57BL/1 mice carry tumorigenic virus, the evidence suggests a viral etiology. 相似文献
18.
研究市场上常见的5种饲料对C57BL/6J小鼠及KM小鼠生长和繁殖的影响,为实验小鼠生产中合理使用饲料提供科学依据.实验选取3周龄C57BL/6J小鼠和KM小鼠各250只,每种鼠随机分为5组,每组50只,雌雄各半,饲喂A,B,C,D,E共5种不同厂家的实验动物维持饲料,测定小鼠4～8周龄的体质量和脏器系数.另选取C57BL/6J小鼠及KM小鼠性成熟小鼠各150只,雌雄各半,每种鼠随机分为5组,每组15对,饲喂A,B,C,D,E共5种不同厂家的实验动物繁殖饲料,测定母鼠的产仔数、连胎率.结果表明:①5种维持饲料均能满足小鼠的生长需求, C饲料和E饲料更符合小鼠生长的营养需求.②5种饲料饲喂的小鼠器官指数正常.③5种繁殖饲料饲喂的母鼠第1,2胎的产仔数差异不具有统计学意义(p0.05),说明产仔数更多取决于遗传因素,本次调查的几种饲料对其影响较小.合理选择实验小鼠所需饲料,利于实验数据的稳定. 相似文献
19.
不同品系小鼠体外受精方法的研究 总被引：5，自引：0，他引：5
对CD-1、B6DF1和C57BL／6小鼠的卵母细胞采用直接、去卵丘细胞、切割透明带法处理后,分别进行体外受精、体外培养和胚胎移植试验。结果表明：CD-1和B6DF1小鼠体外受精率及受孕率均高于近交系C57BL／6小鼠。3个品系小鼠卵母细胞3种不同处理试验,受孕率差异均不显著;去卵丘细胞卵体外受精率(11％～23％)均显著低于卵丘卵母细胞复合体的受精率(34％～60％)和切割透明带卵的受精率(48％～65％),而C57BL／6小鼠的卵经切割透明带后体外受精率显著高于卵丘卵母细胞复合体的受精率。C57BL／6小鼠理想的体外受精方法为切割透明带法,而CD-1、B6DF1小鼠切割透明带卵受精率与其卵丘卵母细胞复合体的受精率差异均不显著,因此这2个品系可直接用卵丘卵母细胞复合体进行体外受精,其方法简单、有效。 相似文献
20.
Total cholesterol concentrations in muscle, liver, and plasma do not differ significantly between adult male C57BL/10J and DBA/2J mice. In the adrenal glands of these two strains, of their hybrids, and of AC mice, concentrations of free cholesterol vary by 5 percent. Adrenals from C57 mice, however, contain six times as much esterified cholesterol as adrenals from AC or DBA mice. The intermediate concentrations of cholesterol esters in F(1) hybrids suggest that the difference in this measure is inherited additively. The finding of variation in adrenal cholesterol within a species is useful for the further study of the role of cholesterol in steroidogenesis by means of genetic analysis. 相似文献