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61.
62.
K Uchio-Yamada N Manabe M Yamaguchi N Akashi Y Goto Y Yamamoto A Ogura H Miyamoto 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2001,63(11):1171-1178
Fibrotic degeneration was examined in the kidneys of ICR-derived glomerulonephritis (ICGN) mice, a novel inbred mouse line with a hereditary nephrotic syndrome of unknown etiology considered to be a good model of human idiopathic nephrotic syndrome. In the present study, we histochemically revealed changes in accumulation of extracellular matrix (ECM) components and in localization of integrins, cellular receptors for ECM, in the kidneys of ICGN mice with the progression of renal failure. Excessive accumulation of basement membrane (laminin and collagen IV) and interstitial (type III collagen) ECM components were demonstrated in the glomeruli and tubulointerstitum of ICGN mice. Marked deposition of type I collagen and tenascin was seen only in the glomeruli of ICGN mice but not in those of ICR mice as normal controls. Increased expression of integrin alpha1-, alpha2-, alpha5- and beta1-subunits in glomeruli with fibrotic degeneration and abnormal distribution of alpha6-subunit were noted in the kidneys of ICGN mice. Excessive laminin, a ligand of alpha6beta1-integrin, was demonstrated on the tubular basement membrane, but alpha6-subunit diffusely disappeared on the basal side of the tubular epithelial cells. We presumed that abnormal integrin expression in renal tubules causes epithelial cell detachment, and consequently tubular nephropathy, and results in disorder of ECM metabolism causing excessive accumulation of ECM components in the kidneys of ICGN mice. 相似文献
63.
毕节地区位于贵州省西北部,处于云贵高原台面与侧面的结合部,素有高寒山区之称。全区耕地面积43.3万hm2,其中,70%以上耕地分布在海拔1 400 m以上,旱地占86%,以旱地农业为主体。区内年均温12.8℃,降雨量1 000 mm左右,气候凉爽,雨量充沛,十分有利于马铃薯栽培。地区内马铃薯是主要粮食作物之一,播种面积和产量仅次于玉米位居第二,是山区人民的主副食品和发展畜牧业的主要饲料来源。因而马铃薯在毕节地区农业生产中占有举足轻重的地位。全区马铃薯播种面积1999年为14.3万hm2,占全省播种面积的1/3以上,是贵州马铃薯的主产区。就毕节地区得天独厚的地理、自然气候条件,将马铃薯产品生产开发建成一个大的产业是完全可能的。根据市场经济的发展,社会需求的变化,如何加快全区马铃薯产业的形成和发展,是当前急需研究和探讨的重要课题。 1 调整马铃薯的产业方向,明确马铃薯产业的发展目标 马铃薯的营养成分齐全、含量丰富,马铃薯及其产品的市场潜力很大,就毕节地区自然条件和市场需求看,毕节地区马铃薯产业的发展方向和目标可定位在三个方面。 1.1 种薯生产 毕节地区西部的赫章、威宁及中部大方的部分乡镇,气候冷凉,昼夜温差大,马铃薯生长茂盛、健壮,种薯质量好,历来都是本省和邻近省区的种源基地。但由于基地建设及栽培技术不规范,常以“大路货”作种薯调出,影响了市场的拓展。目前发展薯类已成为贵州省和南方许多省区种植业结构调整中的一个重点,抓住这个机遇,把毕节地区建成南方的一个种薯生产和供应基地是完全可能实现的。 相似文献
64.
600 g 冰冻羊垂体经过酸性溶液提取、硫酸铵的分级分离和 DEAE-纤维素柱层析得纯品(1),其得率为0.08g/kg,最后将部分纯品(1)过 Sephadex G-100分子筛,得到高纯的羊生长激素[纯品(2)]。提取的羊生长激素具有相当高的理化均一性,纯品(2):聚丙烯酰胺凝胶电泳呈现一条主带和二条酸性小带;聚丙烯酰胺等电聚焦电泳呈现二条带,其等电点分别为 pH7.35和 pH7.40,SDS—电泳呈现二条很难分开的带,其平均分子量为20 100道尔顿;用DNS-CI 法测得的 N-末端氨基酸是2个,丙氨酸和苯氨酸。纯品(1)理化均一性稍差:SDS—电泳较纯品(2)多出两条分子量低的带;等电聚焦电泳多出六条酸性小带。除此之外,其他理化性质同纯品(2)。用大白鼠胫骨实验测定生物活性,测得纯品(1)可使垂体大白鼠胫骨软骨盘的宽度相对增加79%。未对纯品(2)进行生物活性测定。用羊催乳素放射免疫药盒测定,纯品(1)和纯品(2)与羊催乳素均无交叉反应。 相似文献
65.
Y. SANTOS I. BANDIN S. NUÑEZ K. GRAVNINGEN A. E. TORANZO 《Journal of fish diseases》1991,14(3):407-411
Abstact. The potency of a whole-cell bacterin (WCB) and a toxoid enriched whole-cell vaccine (WCEB) administered intraperitoncally into rainbow trout, Oncorhynchus mykiss (Richardson), were compared. The most effective vaccine was further evaluated by bathing turbot, Scophthalmus maximus (L.). These vaccines were composed of three strains of V. anguillarun , of the serotypes 01 and 02. Both vaccines conferred the highest protection against strains of serotype 01 within 4 weeks. With the toxoid enriched vaccine giving the best results (77 RPS). When trout were revaccinated after 7 weeks with this vaccine, good protection was achieved against strains of serotypes 01 and 02. Interestingly, when the WCEB was administered by bath to turbot, acceptable levels of protection against strains of both serotypes were obtained after 4 weeks of immunization. 相似文献
66.
Significant differences of callus induction, green plant regeneration and culture efficiency were observed among restorer lines and their hybrids in rice. Average callus induction percentage of F1, hybrids was about twice that of their parents. Twenty doubled haploid (DH) lines that showed normal fertility with both indica and japonica CMS lines, were selected as widely compatible restorers (WCRs). TG8 derived from CPSLO17/Minghui 63 not only showed normal fertility to both indica and japonica test varieties and CMS lines, but also exhibited superior agronomic traits, in particular short plant, desired plant type, high tillerability, large panicles, good grain quality and resistance to rice blast disease. Strong heterosis for yield was observed in crosses between indica or japonica CMS lines and TG8. TG8 possessed a dominant, widely compatible gene (WCG) that was inherited from the variety CPSLO17. Results confirmed that the anther culture technique is a quick and effective way of developing widely compatible restorers in rice and that it is applicable to the direct use of intersubspecific heterosis with the three-line method. 相似文献
67.
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69.
不同种类杀虫剂对斜纹夜蛾的药效评价 总被引:7,自引:1,他引:6
通过室内测定和田间药效试验,评价了有机磷、拟除虫菊酯、氨基甲酸酯、昆虫生长调节剂、苯基吡唑类、抗生素及植物性农药等7大类杀虫剂对斜纹夜蛾的效应,结果表明,毒死蜱、保得、万灵及抑太保对斜纹夜蛾具有优良的防效,可作为首选杀虫剂进行交替使用 相似文献
70.