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71.
72.
半胱亚磺酸脱羧酶(CSD)基因在大鼠睾丸组织中的表达及其序列分析 总被引:1,自引:0,他引:1
试验根据大鼠肝脏牛磺酸生物合成关键酶——半胱亚磺酸脱羧酶(CSD)基因已知核苷酸序列,设计了1对特异的寡核苷酸引物,对提取的睾丸组织总RNA进行RT-PCR扩增,扩增出468 bp的DNA片段,在国际上首次证明CSD基因在大鼠睾丸组织中存在表达,即牛磺酸可在大鼠睾丸组织中生物合成。测定了扩增的睾丸组织CSD基因核苷酸序列,并与已知肝脏CSD基因核苷酸序列及其对应的氨基酸序列作了同源性分析。结果表明:睾丸组织CSD基因核苷酸序列同已知肝脏CSD基因核苷酸序列的同源性为99.8%,其对应氨基酸序列的同源性为100%。 相似文献
73.
探讨中药复方对实验性大鼠骨质疏松症的预防和治疗作用,并在此基础上探索该中药对成年经产高龄母猪骨质疏松症的预防效果。对102只3月龄SPF级SD雌性大鼠用维甲酸造模并进行中药防治试验,造模结束和药物治疗结束后对大鼠进行骨密度检测、骨组织形态检测与血液生化指标(Ca、P、BALP和TRACP-5b)检测。同时,将35头6胎~8胎经产高龄母猪,4岁~5.5岁体重220kg^300kg长大二元杂母猪随机分为空白组、中药复方高、中、低(B1、B2、B3)3个剂量组,连续给药20d,检测母猪血液生化指标(Ca、P、TRACP-5b、CTX-Ⅰ、BALP和PINP)。结果表明,与模型组相比,中药组大鼠血清水平有显著降低,骨密度增加,骨微观结构得到改善;与空白组相比,中药中剂量组和高剂量组母猪血清BALP及PINP水平显著升高,TRACP-5b及CTX-Ⅰ水平显著降低。结果表明该中药复方制剂对大鼠和猪骨质疏松症的治疗有良好效果。 相似文献
74.
Tsukasa OKANO Katsuhi NAKATA Yumiko NAKAYA Takashi NAGAMINE Manabu ONUMA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(6):637-642
The Ryukyu long-furred rat, Diplothrix legata, is a large rodent
distributed only on Amami-ohshima Island, Tokuno-shima Island and Okinawa-jima Island,
Japan. This animal is endangered as a result of deforestation, predation by introduced
carnivores and mortality caused by vehicles. We performed theriogenological examinations
of 32 male and 25 female Ryukyu long-furred rats carcasses collected from wild populations
on northern Okinawa-jima Island from December 2005 to September 2013. Adult males had
remarkably large preputial glands. Seminiferous diameter of adult was significantly small
(136 ± 28 µm, n=8) from April to August. Numerous spermatozoa were
observed from September through February, and seminiferous diameter was significantly
large (216 ± 27 µm, n=12) during this time in adults; testes length
changed in a similar pattern. These findings indicate that the mating season may occur
from September through February. Size (body length) at sexual maturity was estimated to be
>560 mm in both sexes. From observation of corpora lutea and placental scars, litter
size was estimated to range from 2 to 12 (average=6, n=4). These results provide
fundamental knowledge that will be beneficial for in situ and ex
situ conservation of this rare species. 相似文献
75.
苏太仔猪FUT1基因M307位点多态性与F18大肠杆菌抗病相关性的体外鉴定 总被引:2,自引:0,他引:2
采用PCR-RFLP方法检测了江苏苏太断奶仔猪FUT1基因M307位点等位基因多态性分布,在所检的49头仔猪中,GG基因型个体16头,AG基因型19头,AA基因型14头。在此基础上,制备上述不同基因型个体仔猪小肠上皮细胞,分别与表达F18ab菌毛的野生型大肠杆菌、表达F18ac菌毛含fed操纵子全基因的重组大肠杆菌和V型系统表面分泌表达F18abFedF亚单位的重组大肠杆菌进行体外黏附试验和黏附抑制试验。研究结果表明:FUT1基因M307位点中GG型和AG型仔猪小肠上皮细胞均能黏附上述3种大肠杆菌,而AA型个体小肠上皮细胞则不能黏附。将上述3种大肠杆菌分别与抗F18ab菌毛高免血清、F18ac菌毛高免血清及抗F18abFedF亚单位单因子血清作用后,则失去黏附仔猪肠上皮细胞能力。上述结果对苏太猪从体外试验上证明了FUT1基因M307位点多态性与断奶仔猪腹泻和水肿病存在着直接的相关性。 相似文献
76.
Lechowski R Bielecki W Sawosz E Krawiec M Kluciński W 《Veterinary research communications》1999,23(1):1-14
Sixty-four Wistar rats were divided into 8 equal groups and kept for 36 days in individual boxes. Three of the groups were given full synthetic diets containing various animal fats: beef tallow, pork fat or fish oil. A control group was fed the diets without the fat. The other four groups were fed the same diets with lecithin supplementation. At the end of experiment, sections taken from the liver were stained with haematoxylin–eosin and Sudan III to indicate fat infiltration. Liver enzyme levels, total bilirubin, albumin and two products of lipd metabolism were measured in serum from all the animals. The addition of lecithin to the diets did not influence the level of enzymes in the serum except in rats fed the diet containing beef tallow. A relationship between the type of diet, lecithin supplementation and the total cholesterol concentration in serum was observed. The concentration of HDL-cholesterol was only influenced by lecithin supplementation and that of triglycerides by the type of fat in the diet. The addition of lecithin to the diet was associated with proliferation of Kupffer cells, and an increased number of binuclear cells. Fatty degeneration of hepatocytes was less pronounced in all groups following lecithin supplementation. Lecithin supplementation of the diet did not elicit any pathological lesions and may be considered as a hepatocyte protector. This favourable effect of lecithin was most marked in the group of rats fed the fish oil. 相似文献
77.
78.
旨在揭示大肠埃希菌内毒素(ET)对大鼠小肠黏膜的结构、绒毛长度、上皮内淋巴细胞(IEL)的数量和分布的影响,并探讨多价阳离子A(CA)对上述指标的保护效应。选用72只140g~150g SPF级SD大鼠随机分为3组,即对照组、ET组和CA保护组,经相应处理后分别在3、4、8、12h采集十二指肠、空肠组织作为检测样本,制备病理组织切片,HE染色并利用图像分析系统进行分析。ET组十二指肠和空肠绒毛长度在3、4、8、12h均显著低于对照组和CA保护组(P0.01),ET组十二指肠、空肠IEL数量在3、4、8、12h均显著低于对照组(P0.01);CA保护组十二指肠和空肠IEL数量在4、8、12h均显著高于ET组(P0.01)。结果显示,ET在不同程度上能够破坏小肠黏膜的正常组织结构,降低小肠绒毛长度,减少IEL的数量,从而影响小肠正常的吸收和免疫功能,而CA则能明显降低ET所导致的毒性作用,发挥其保护效应。 相似文献
79.
80.
Background:The experiment evaluated the effect of nutrition levels and sex on the growth performance,carcass characteristics and meat quality of F1 Angus × Chinese Xiangxi yellow cattle.Methods:During the background period of 184 d,23 steers and 24 heifers were fed the same ration,then put into a2×2×2 factorial arrangement under two levels of- dietary energy(TON:70/80%DM),protein(CP:11.9/14.3%DM)and sex(S:male/female) during the finishing phase of 146 d.The treatments were-(1) high energy/low protein(HELP),(2) high energy/high protein(HEHP),(3) low energy/low protein(LELP) and(4) low energy/high protein(LEHP).Each treatment used 6 steers and 6 heifers,except for HELP- 5 steers and 6 heifers.Results:Growth rate and final carcass weight were unaffected by dietary energy and protein levels or by sex.Compared with the LE diet group,the HE group had significantly lower dry matter intake(DMI,6.76 vs.7.48 kg DM/d),greater chest girth increments(46.1 vs.36.8 cm),higher carcass fat(19.9 vs.16.3%) and intramuscular fat content(29.9 vs.22.8%DM).The HE group also had improved yields of top and medium top grade commercial meat cuts(39.9 vs.36.5%).The dressing percentage was higher for the HP group than the LP group(53.4 vs.54.9%).Steers had a greater length increment(9.0 vs.8.3 cm),but lower carcass fat content(16.8 vs.19.4%) than heifers.The meat quality traits(shear force value,drip loss,cooking loss and water holding capacity) were not affected by treatments or sex,averaging 3.14 kg,2.5,31.5 and 52.9%,respectively.The nutritive profiles(both fatty and amino acid composition) were not influenced by the energy or protein levels or by sex.Conclusions:The dietary energy and protein levels and sex significantly influenced the carcass characteristics and chemical composition of meat but not thegrowth performance,meat quality traits and nutritive profiles. 相似文献