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571.
Rivera MN Kim WJ Wells J Driscoll DR Brannigan BW Han M Kim JC Feinberg AP Gerald WL Vargas SO Chin L Iafrate AJ Bell DW Haber DA 《Science (New York, N.Y.)》2007,315(5812):642-645
Wilms tumor is a pediatric kidney cancer associated with inactivation of the WT1 tumor-suppressor gene in 5 to 10% of cases. Using a high-resolution screen for DNA copy-number alterations in Wilms tumor, we identified somatic deletions targeting a previously uncharacterized gene on the X chromosome. This gene, which we call WTX, is inactivated in approximately one-third of Wilms tumors (15 of 51 tumors). Tumors with mutations in WTX lack WT1 mutations, and both genes share a restricted temporal and spatial expression pattern in normal renal precursors. In contrast to biallelic inactivation of autosomal tumor-suppressor genes, WTX is inactivated by a monoallelic "single-hit" event targeting the single X chromosome in tumors from males and the active X chromosome in tumors from females. 相似文献
572.
Gastrointestinal nematodes (GIN) continue to hinder small ruminant production because of anthelmintic resistance and lack of effective products for GIN control in organic production. The objective of this study was to examine the effectiveness of a commercially available certified organic garlic product, fresh garlic juice, or garlic bulbs as an anthelmintic to control GIN in goats and papaya seeds for GIN control in lambs. In the first experiment, weaned meat goat kids were administered water or a commercial garlic juice product (n = 7/treatment). In the second experiment, kids were administered water, fresh garlic juice, or fed garlic bulbs (n = 9 or 10/treatment). In a third experiment, lambs were administered nothing or papaya seed in water (n = 12/treatment). Naturally infected goats were supplemented with bermudagrass hay and corn/soybean supplement in the first experiment or maintained on bermudagrass pasture in the second experiment or lambs grazed mixed grasses in the third. Blood and fecal samples were collected on Days 0, 7, and 14 after administration of treatment to examine changes in blood packed cell volume (PCV) and fecal egg counts (FEC). PCV and FEC were similar by Day 14 between kids treated with a commercial garlic juice and water in the first experiment. Similarly, PCV was not different among treatment groups in the second experiment. FEC of the garlic juice group was lower than the other two groups on Day 0, but was similar among groups by Day 14. Deworming was required in one goat within each treatment group by Day 7 and in three kids in the garlic juice group and two in the garlic bulb group by Day 14. No changes in PCV or FEC were apparent in response to papaya seed compared with untreated lambs. Based on the alternative plant products used in this study, garlic or papaya seed is not recommended as an aid to control GIN in goats or lambs. 相似文献
573.
为探究不同有机肥对高寒地区燕麦草产量及土壤肥力的影响,本试验共设置 5 个不同的施肥处理,生育期 120 d后测定了燕麦鲜草产量和干草产量,并分析了土壤的理化性质。试验结果表明:不同的有机肥对高寒地区燕麦草产量影响较大,燕麦鲜草产量结合播种施 1 号燕麦专用有机肥作基肥,在分蘖期追施 2 号燕麦专用有机肥处理组最高,为 82 000 kg/hm2,本试验生产的有机肥处理组次之。此外,经土壤化学性质检测,各处理组有机质含量均较施肥前有所增加,本试验生产的有机肥处理组有机质、全氮、全磷、全钾含量最高,说明以牛羊粪为原料通过益生菌发酵自制的有机肥可以有效提高土壤肥力水平。 相似文献
574.
日粮中添加油料籽实对奶牛生产性能及乳脂脂肪酸组成的影响 总被引:4,自引:0,他引:4
本文旨在研究在日粮中添加油料籽实对中国荷斯坦奶牛乳脂肪酸组成及生产性能的影响,为提高奶牛乳脂中共轭哑油酸(CLA)含量,改善乳品质寻找合适的途径.试验选取16头泌乳前期(62±11)d、胎次一致(3胎)、泌乳量相近的中国荷斯坦奶牛,随机分为4组(对照组、菜籽组、亚麻籽组、葵花籽组),每组4头.试验共进行40 d(预试期10 d,正试期30 d),分别在正试期第1天、第15天和第30天测定乳产量、分析乳成分,用气相色谱仪分析乳脂肪酸组成.结果表明,与对照组相比,日粮中添加油料籽实,显著提高了奶牛的泌乳性能(P<0.05),降低了乳脂率(P<0.05),对乳中其他常规成分影响差异不显著(P>0.05);日粮中添加葵花籽后乳脂中CLA含量提高98.28%(P<0.05).菜籽组、亚麻籽组、葵花籽组的乳脂中C14:0和C16:0的含量分别比对照组降低了17.86%和26.75%、15.99%和27.18%、21.99%和21.74%.乳脂中多不饱和脂肪酸(PUFA)含量分别比对照组提高40.83%、47.06%和41.52%(P<0.05).乳脂中的t11-C18:1(x)与CLA(y)的比例(%)存在正相关性,y=0.34x 0.20,R<'=0.696 2(P<0.01).日粮中添加植物油籽显著提高了乳脂中CLA、PUFA的比例,降低了C14:0和C16:0的比例,改善了乳脂的构成,提高了乳品质. 相似文献