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61.
利用建立的小鼠微卫星检测方法,对来源于2个单位的近交系BALB/c小鼠和封闭群ICR小鼠进行了遗传分析,结果发现A单位BALB/c小鼠发生了遗传污染,有部分小鼠在部分微卫星位点发生了变异,而B单位BALB/c小鼠在所有的检测位点上的结果都与预期的BALB/c小鼠位点一致;对ICR 小鼠分析结果发现A单位ICR小鼠在22个位点的平均杂合度为0.379,平均多态信息量为0.308,属中度多态,B单位ICR小鼠的平均杂合度为0.287,平均多态信息量为0.227,属低度多态.结果表明微卫星标记可用于检测近交系小鼠的遗传质量,也可用于分析封闭群小鼠的遗传多态性,为一种有潜力的实验动物遗传学检测标记.  相似文献   
62.
被毛突变无毛小鼠皮肤及毛结构观察   总被引:5,自引:1,他引:5  
对国内首次发现并培育成群的BALB/c突变小鼠的3种表型(无毛、全毛、中间态)的皮肤组织及毛结构进行了观察。结果表明,无毛小鼠仅具有非常短(1~2mm)、细且弯曲的绒毛,其毛于中心为空泡状,缺乏髓质。无毛小鼠表皮、真皮、皮下组织结构基本与全毛、中间态小鼠相同,但其毛生长周期不健全;毛球位置浅表,数目少,排列不规则;皮脂腺异常增生。推测其被毛结构异常是由毛自身结构异常所致。该小鼠外观似裸鼠,能在普通条件下生长繁殖,可望成为某些皮肤病等研究的动物模型。  相似文献   
63.
A non-narcotic anesthetic combination (Me/Mi/Bu) of medetomidine (Me), midazolam (Mi), and butorphanol (Bu) has been recommended as the injectable anesthesia in mice. An original dose of Me/Mi/Bu (0.3/4.0/5.0 mg/kg) has provided sufficient anesthetic duration of 40–50 min in mice. In addition, atipamezole is available for reversal of Me/Mi/Bu anesthesia. As an adverse effect of Me/Mi/Bu anesthesia, however, severe hypothermia has been also observed in mice. In the present study, we investigated 1) the main agent in Me/Mi/Bu to cause of hypothermia, 2) the effects of the differential doses of atipamezole on hypothermia induced by Me/Mi/Bu anesthesia and on the plasma levels of creatinine phosphokinase and transaminases, and 3) those recommended doses for preventing hypothermia induced by Me/Mi/Bu anesthesia in mice. The results suggested that 1) the α2-agonist medetomidine is most likely to induce hypothermia in mice under Me/Mi/Bu anesthesia, 2) the antagonism of atipamezole within proper dose range is effective in promoting the recovery from Me/Mi/Bu-induced hypothermia, and 3) Me/Mi/Bu at the recommended dose of 0.2/6.0/10.0 mg/kg enable to provide anesthetic effects for 40 min and is more considerable to prevent the hypothermia than that at the original dose of 0.3/4.0/5.0 mg/kg.  相似文献   
64.
齐斌文 《绿色科技》2021,(6):202-204,218
采用文献资料法对食用菌多糖抗运动疲劳的研究进展情况进行了研究.结果表明:食用菌多糖提取方法不同而食用菌多糖的提取率也不相同,超声波法+复合酶法及微波法提取食用菌多糖提取率较高,2种方法科学合理的结合提取食用菌多糖以及不同产地、品种和不同部位提取率是未来学者们需要研究的领域;目前,只是对极少部分食用菌多糖抗运动疲劳进行了...  相似文献   
65.
In mammals, long bones are formed by ossification of a cartilaginous mould during early stages of development, through the formation of structures called the primary ossification centre, the secondary ossification centres (SOCs) and the physeal cartilages (PCs). The PC is responsible for long bone growth. The morphology of the PC and the SOCs varies during different stages of femoral growth. In this respect, several details involving the process of murine femoral development are lacking. In the present study, a morphological characterization of femur development from the embryonic period to adulthood in mice was studied using micro‐computed tomography (micro‐CT). To achieve this aim, femora were collected at embryonic day (E) 14.5, E16.5 and E18.5 and at postnatal day (P)1, P7, P14, P35, P46 and P52. CT images were obtained using a micro‐CT scanner (X‐SkyScan 1172; Micro Photonics) and analysed using the micro‐CT 3D visualization software Mimics (Materialise NV, Leuven, Belgium) and NRecon (Micro Photonics). The results of the present study revealed that the femur and its PCs and SOCs undergo morphological changes during different stages of development, including changes in their shape as well as position and thickness. These changes may be due to the response of the femur to mechanical loads imposed by muscle surrounding the bone during these stages of development. The result of the present study is important to improve our knowledge related to ossification and growth patterns of mouse femur during development.  相似文献   
66.
The pathogenesis of infectious agents with human tropism can only be properly studied in an in vivo model featuring human cells or tissue. Humanized mice represent a small animal model featuring human cells or tissue that can be infected by human-specific viruses, bacteria, and parasites and also providing a functional human immune system. This makes the analysis of a human immune response to infection possible and allows for preclinical testing of new vaccines and therapeutic agents. Results of various studies using humanized mice to investigate pathogens with human tropism are presented in this review. In addition, the limitations of humanized mice and methods to improve this valuable animal model are discussed.  相似文献   
67.
为探讨液态甲醛对雄性小鼠生殖细胞的毒性和致突变作用,选用雄性昆明种小鼠为研究对象,进行液态甲醛腹腔染毒,7 d后测定睾丸脏器系数、精子数目、精子形态及精子畸形率及精子微核率。结果表明:中、高剂量组(2.0、20.0 mg/kg)甲醛具有明显的生殖毒性,小鼠睾丸指数、精子数量明显降低,小鼠精子存活率、活动率都受到显著影响;中、高剂量组的精子畸形率、微核率与阴性对照组比较,有显著性差异。由此说明,液态甲醛对雄性小鼠的生殖细胞具有明显的毒性和致突变作用。  相似文献   
68.
In order to study the tolerance dose of Kunming mice to montmorillonite as a mycotoxin adsorbent in diets,the experiment selected 60 healthy male Kunming mice with initial average body weight of (17±0.12)g,randomly divided them into 5 treatments with two replicates per group and 6 mice per replicate.Five experimental diets were added to 0 (control group),0.5%,1%,2% and 5% montmorillonite,respectively.After 30 days,the growth performance,nutrients apparent digestibility,serum biochemical indices and internal organization were tested to determine the tolerance dose of montmorillonite for Kunming mice.The results showed that the ADFI was significantly increased in 0.5% group (P< 0.05),while there were no significant differences in ADFI and ADG between 1% group and control group (P> 0.05),then the ADFI was significantly decreased with the increasing of montmorillonite supplemental level (P< 0.05).The ADG in 2% group had no significant difference when compared with the control group (P> 0.05),while significantly lower than that in 0.5% and 1% groups (P< 0.05).The apparent digestibility of DM,CP and EE showed no significant effect at any level of montmorillonite (P> 0.05).Serum ALT,AST activities and MDA content were gradually increased with the montmorillonite supplemental level increasing,and that in 1%,2% and 5% groups were significantly higher than that in control group (P< 0.05),but there were no significant differences between 0.5% group and control group (P> 0.05).Tissue sections showed that mice livers were damaged in varying degrees when the montmorillonite supplemental level was 5%.In conclusion,based on a comprehensive consideration of all indexes,it could be seen that the tolerance dose of the tested montmorillonite for Kunming mice was between 0.5% and 2% when mycotoxin contents in diets were in security range.  相似文献   
69.
研究表明,仙游县为农区鼠害重发区,田间优势种为黄毛鼠,农舍优势种为黄胸鼠,防治适期为4—5月和8—9月两个害鼠活动高峰期;化学药物防治是综合防治的主要措施;准确掌握鼠情动态,选择高效、安全杀鼠剂,采用正确的投饵技术,才能取得理想的灭鼠效果。  相似文献   
70.
采用高脂饲料建立小鼠肥胖模型,以小鼠体重、Lee's指数、脂肪湿重、脂肪系数、血清总胆固醇(TC)、甘油三脂(TC)及高密度脂蛋白(HDL-C)等指标的变化,研究章鱼胺对小鼠的减肥作用.结果表明,肥胖对照组小鼠较普通对照组小鼠的体重、脂肪湿重、脂肪系数、血清总胆固醇(TC)、甘油三脂(TG)及高密度脂蛋白(HDL-C)含量均显著增加(P<0.05),表明营养肥胖模型构建成功;章鱼胺各剂量组及阳性对照组中小鼠的体重、脂肪湿重、脂肪系数、血清总胆固醇(TC)与模型组存在显著性差异(P<0.05),其中Lee's指数和甘油三脂(TG)的中、高剂量组与模型组存在显著性差异(P<0.05);章鱼胺对营养性肥胖小鼠有一定的减肥降脂作用.  相似文献   
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