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21.
谷胱甘肽(GSH)对绵羊细管冻精质量的影响   总被引:1,自引:0,他引:1  
研究了在绵羊冻精稀释液中添加不同浓度(0、1、2、2.5、3 mmol/L)的谷胱甘肽(GSH)对细管冻精质量及体外受精的影响。结果显示:在绵羊精子的冷冻稀释液中添加1 mmol/L GSH具有最好的效果,可以显著地增加冷冻解冻精子的活力以及精子质膜、顶体膜和DNA的完整性,还可以在一定程度上提高体外受精的卵裂率及囊胚率。  相似文献   
22.
利用抗补体法测定成年公牛精清抑制物(BSPI)的含量,以研究BSPI与精液品质、公牛年龄和季节之间的关系。结果麦明,BSPI的平均含量为696±256单位(u)/ml(n=75),不同公牛存在明显的个体差异。BSPI含量与新鲜精液的精子活力无关。公牛射精量与BSPI含量呈负相关(r=-0.9163,P<0.05)。冬季BSPI含量明显高于夏季(P<0.001)。试验未发现公牛年龄和精子密度与BSPI含量之间的相关。  相似文献   
23.
将Jcl-lcr系18日龄雌性小白鼠28只分为4组,从20日龄时摘除卵巢,28日龄开始,第1组连续给穿山甲、王不留行煎液,每天口服0.2ml(相当于生药0.1g);第2组、第3组、第4组(对照组)以相同方法分别给红花、淫羊藿、益母草煎液和麦芽、莱菔子等煎液及蒸馏水。第45日龄取材检查,结果显示第1组的乳腺分枝数与对照组乳腺分枝相比,差异不显著。同样第1组的乳腺腺泡数与对照组乳腺腺泡数相比,差异也不显著。结论穿山甲、王不留行对摘除卵巢未性成熟小白鼠乳腺发育无作用;穿山甲、王不留行对未性成熟小白鼠乳腺实质发育的促进作用是通过卵巢所致。  相似文献   
24.
本研究采用不同方法对赤峰山杏仁进行脱苦去毒的处理,筛选出最佳去毒方法,即用0.3%HCl,0.5% Na_2CO_3去毒处理法。用该处理法得到的山杏仁白嫩可口,香味浓。苦杏仁甙含量从3.67%降低到0.13%。  相似文献   
25.
Two polymerase chain reaction (PCR) assays specific for glycoprotein B (gB) and glycoprotein E (gE) gene detection, respectively, were adopted for the detection of bovine herpesvirus-1 (BHV-1) in naturally infected bulls. The methods were tested on bovine semen artificially inoculated with BHV-1 and were compared with an optimised virus isolation method. Raw and extended semen samples were diluted in minimal essential medium (MEM) and spiked with equal dose of BHV-1. The extended semen was found to be more toxic for the cells than the raw semen, while the viral DNA could be detected by the PCR method in all tested dilutions of raw and extended semen samples. The sensitivity of both methods was compared also for BHV-1 detection in semen, nasal swabs and leucocytes of a seropositive bull in a different time period after virus reactivation with dexamethasone treatment. The sensitivity of virus detection by the PCR method was equivalent to that of virus isolation in cell culture. However, PCR was shown to be faster and easier to perform and may be a good alternative to virus isolation especially when bovine semen has to be screened for BHV-1 prior to artificial insemination.  相似文献   
26.
27.
蓝莓主要栽培技术及其在湖南省的发展前景   总被引:1,自引:0,他引:1  
介绍了蓝莓保健价值、经济价值和主要栽培技术。针对湖南省的土壤和气候特点,推介了适合湖南省栽培的蓝莓品种,并提出了在湖南省发展蓝莓的建议。  相似文献   
28.
This study investigated the effects of ascorbic acid and α-tocopherol supplementation on semen quality parameters of equine thawed-frozen semen. Semen was divided in seven different treatments in a final concentration of 100 × 106 sperm/mL by using Gent extender containing no supplements (control) and the following supplements with three different concentrations: α-tocopherol (0.5, 1, and 2 mM) and ascorbic acid (0.45, 0.9, and 1.8 g/L). After thawing, all samples were maintained at 37°C, while analyses were performed at 0, 60, and 120 minutes. Evaluation of viability and acrosome status (using Pisum sativum agglutinin conjugated to fluorescein isothiocyanate and propidium iodide), mitochondrial membrane potential (5,5′,6,6′-tetrachloro-1,1′,3,3′tetraethylbenzimidazolyl carbocyanine iodine [JC-1]), membrane lipid peroxidation (LPO; C11-BODIPY581/591), and stability of the plasmatic membrane (merocyanine 540 and Yo-Pro-1) of each sample was determined by flow cytometry. Relative to the control group, supplementation with α-tocopherol improved (P ≤ .05) postthaw membrane LPO, yet the higher concentrations of ascorbic acid (0.9 and 1.8 g/L, respectively) showed a negative effect on membrane LPO. Neither antioxidant significantly increased (P > .05) the acrosome integrity and mitochondrial membrane potential of frozen-thawed spermatozoa, although supplementation with α-tocopherol and ascorbic acid (0.9 and 1.8 g/L, respectively) had a positive effect on membrane integrity and stability (P ≤ .05). For all semen parameters, the lower concentration of ascorbic acid (0.45 g/L) did not show significant differences (P > .05) compared with the control. In conclusion, α-tocopherol seems to be an efficient antioxidant for reducing the oxidative stress provoked by cryopreservation, decreasing lipid peroxidation on equine spermatozoa.  相似文献   
29.
The purpose of the present study was to detect leptospiral DNA by PCR in semen and urine samples of stallions to test for venereal transmission in horses. A total of 10 stallions from four herds were studied, and sampling was conducted in semen and urine for culture and PCR and serum for serology. From the 10 serum samples tested, 6 (60%) were seroreactive. No pure culture was obtained, but leptospiral DNA was detected by PCR in 50% of the semen samples and 30% of urine samples. The present study aimed to detect leptospiral DNA by PCR in semen and urine samples of stallions to test for venereal transmission in horses. Based on these findings, we suggest that there is potential transmission of leptospirosis in horses by sexual transmission.  相似文献   
30.
采用薄层扫描法测定人参皂苷Re含量,测定波长λs=530nm,参比波长λR=650nm.展开剂为(正丁醇∶乙酸乙酯∶水=4∶1∶5)放置后的下层液,显色剂为10%的硫酸乙醇溶液,参考了有关文献[1,2].经测量,人参经过薏苡仁为辅料的加工炮制后的人参皂苷Re含量为0.76mg/g.  相似文献   
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