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1.
Cumulus-oocyte complexes from hormone-stimulated 3-4-week-old (n=43) and 6-7-week-old (n=12) prepubertal lambs were matured in vitro and incubated with unsorted, or X- or Y-spermatozoa separated with a high-speed cell sorter (SX MoFlo)frozen-thawed. Presumptive zygotes were then cultured to the blastocyst stage, and transferred to recipients fresh or after cryopreservation (frozen). Oocyte cleavage was higher (p <0.05) with unsorted (515/926, 55.6%) than X- or Y-spermatozoa (261/672, 38.8% and 229/651, 35.2%, respectively) and blastocyst formation (% zygotes) by Day 9 of in vitro culture was lower (p <0.05) for X- (102/261, 39.1%) than unsorted spermatozoa (249/515, 48.3%), but did not differ between Y-spermatozoa (103/229, 45.0%) and unsorted spermatozoa, or between X- and Y-spermatozoa (p >0.05). For fresh embryos, survival to term was 50.0% (3/6) for unsorted, 0.0% (0/6) for X- and 16.7% (1/6) for Y-spermatozoa-derived embryos (p >0.05), and for frozen embryos was 4.0% (2/50) for unsorted, 9.1% (2/22) for X- and 2.9% (1/34) Y-spermatozoa-derived embryos (p >0.05). Of the two lambs born from X-spermatozoa-derived embryos, one was female (50%), and from the two Y-spermatozoa-derived lambs, both were male (100%), demonstrating that lambs can be produced after the transfer of fresh and cryopreserved IVP embryos derived from prepubertal lamb oocytes and frozen-thawed sex-sorted sperm.  相似文献   
2.
Ginger (Zingiber officinale Roscoe) continues to be used as an important cooking spice and herbal medicine around the world. Scientific research has gradually verified the antidiabetic effects of ginger. Especially gingerols, which are the major components of ginger, are known to improve diabetes including the effect of enhancement against insulin-sensitivity. Aldose reductase inhibitors have considerable potential for the treatment of diabetes, without increased risk of hypoglycemia. The assay for aldose reductase inhibitors in ginger led to the isolation of five active compounds including 2-(4-hydroxy-3-methoxyphenyl)ethanol (2) and 2-(4-hydroxy-3-methoxyphenyl)ethanoic acid (3). Compounds 2 and 3 were good inhibitors of recombinant human aldose reductase, with IC50 values of 19.2 +/- 1.9 and 18.5 +/- 1.1 microM, respectively. Furthermore, these compounds significantly suppressed not only sorbitol accumulation in human erythrocytes but also lens galactitol accumulation in 30% of galactose-fed cataract rat model. A structure-activity relationship study revealed that the applicable side alkyl chain length and the presence of a C3 OCH3 group in the aromatic ring are essential features for enzyme recognition and binding. These results suggested that it would contribute to the protection against or improvement of diabetic complications for a dietary supplement of ginger or its extract containing aldose reductase inhibitors.  相似文献   
3.
试验设喷施百菌清推荐剂量(2 400g/hm2,T1)、加倍剂量(4 800g/hm2,T2)、喷清水(对照)3个处理。探讨蔬菜上百菌清残留量的安全性,开展番茄中百菌清残留的消解规律试验。结果表明,百菌清在番茄上的自然消解速度随施药剂量的增大而减慢。喷药后24h内消解最快,T1处理和T2处理施药后1d的消解率分别为60.22%和27.58%,7d的消解率达91.72%和46.67%,其半衰期分别为4.3d和18.0d。按推荐剂量施药1d后采摘,番茄中百菌清残留量为0.370mg/kg,符合国家相关标准的规定;从人体健康风险角度分析,如果按规范施药,百菌清在番茄上施用安全,产品食用无健康风险。  相似文献   
4.
Soluble fractions of human intestinal cancer and fetal intestinal cell membranes produced delayed hypersensitivity reactions in patients with intestinal cancer. These soluble fractions and perchloric acid extracts of intestinal cancer cells were fractionated by polacrylamide-gel electrophoresis. The Gold carcinoembryonic antigen was found in a region of the gels different from that of the skin reactive antigen.  相似文献   
5.
Antibodies to herpesvirus nonvirion antigens in squamous carcinomas   总被引:3,自引:0,他引:3  
Serums from tumor-bearing patients, cured patients, and normal subjects were examined for antibodies to the separated complement-fixing reactive components of nonvirion antigens of herpesvirus type 1 and type 2. The occurrence of antibodies to the antigens was similar in serums from tumor-bearing patients and cured patients. Antibodies to the antigens were observed among 21 of 24 (87 percent) cervical cancer cases, 44 of 49 (90 percent) laryngeal cancer cases, 15 of 24 (62 percent) cases of squamous cell carcinomas of the head and neck excluding the larynx, 2 of 24 (8 percent) nonsquamous cell cancer cases, and 3 of 51 (6 percent) normal subjects. By contrast, no differences were found in the titers of neutralizing antibodies to the virus in serums from laryngeal cancer patients and controls. The observations support an etiologic role of herpesviruses in cervical cancer and in laryngeal cancer, and possibly other squamous cell cancers of the head and neck.  相似文献   
6.
Variation in haematological parameters of Nigerian native chickens was studied using 60 clinically normal frizzle-feathered, naked-neck, and normal-feathered native chickens. These included red blood cell count, haemoglobin, packed cell volume, white blood cell count, mean corpuscular volume, mean corpuscular haemoglobin concentration, serum glucose, urea, cholesterol, albumin, globulin and creatinine. Normal-feathered birds had higher (p < 0.05) mean values compared to frizzled and native neck genotypes except for albumin, red blood and white blood cells, and mean cell haemoglobin concentration. Males generally had higher mean values than their female counterparts across all genotypes. Correlation coefficients among the parameters were significant (p < 0.001) with r values ranging from 0.26 between red blood cell and mean corpuscular haemoglobin to 0.92 between red blood cell and cholesterol. Sufficient genetic variation therefore exists for haematological parameters among Nigerian native chickens that may represent indicator traits for further study. However, the application of molecular tools will provide better understanding and application of these differences.  相似文献   
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9.
小麦骨干亲本生选6号的赤霉病抗性遗传分析   总被引:1,自引:0,他引:1  
为研究生选6号对黄淮麦区小麦赤霉病抗性改良效果,以黄淮麦区矮抗58、周麦25、周麦27、兰考161等4个主栽品种(系)为母本,以生选6号为父本,配制杂交组合,分别在长江中下游地区(上海崇明、安徽滁州)和黄淮地区(河南兰考)对4个组合F2群体进行赤霉病抗性鉴定。结果表明,4个组合的F2群体赤霉病抗性较感病亲本均显著提高,平均病小穗率在18.4%~31.2%之间,均达到中抗水平。4个群体的个体抗性级别主要集中在抗病和中抗,平均约占80%;而中感、感病和高感很少,平均占比20%左右。矮抗58/生选6号F2群体在滁州和兰考两个不同生态区域的抗性差异显著,虽然两地均达中抗水平,但滁州点抗性明显优于兰考点。主要表现为兰考点高感单株数是滁州点的7.4倍,中抗单株数却不到滁州点的1/2。同时,兰考点抗感比为65∶35,而滁州点为89∶19,这种现象应该与当年两地气候差异有关,可能黄淮冬麦区当年气候更适合赤霉病发病,也与长江中下游品种大多中抗以上而黄淮品种大多为高感品种的事实相一致。此外,抗性单株从F2到F3,发生了接近3∶1的抗感分离,F3抗性单株的平均病小穗率为20.2%,仍保持较强赤霉病抗性。上述结果表明,生选6号可以作为骨干亲本,广泛用于黄淮冬麦区小麦赤霉病抗性的改良。  相似文献   
10.
钙调素与核酸在梨花芽分化中的动态研究   总被引:1,自引:0,他引:1  
以梨为试格,对成花过程中CaM和核酸的含量进行了分析测定,结果表明;短枝芽的CaM含量在成花的发端期成倍增加形成高峰,而新梢芽却一直保持较低的水平;短果枝叶的CaM与新梢叶有着相近的变化趋势。但在成花前后,短果枝叶的CaM含量要明显高于新梢叶的,短枝芽所含核酸,尤其是RNA开始回升时与CaM的峰值相吻合,并且在整个成花期间都呈上升的趋势。  相似文献   
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