Opening angles and residual strains in normal rat trachea

The no-load state and zero-stress state o1 the normal rat trachea were analyzed. It was found that there exist compressive residual strains in the inner wall region of the rat trachea and tensile residual strains in the outer wall region. The fact that the opening angle of the rat trachea cut at the cartilaginous region is significantly larger than that cut at the muscular portion shows that residual strains exist mainly in the muscular region in the rat trachea. It was also indicated that the opening angles and residual strains expressed by cutting at the muscular portion are basically identical along longitudinal location and those expressed by cutting in the cartilaginous region tend to increase in the longitudinal direction in the normal rat, and that there exists quantitatively positive correlation between the opening angles and residual strains in rat trachea. The results will help to further understand the opening angles and residual strains in the trachea and study tracheal remodeling in response     

离子束在生物品种改良中的应用研究进展

辐射诱变育种是利用各种射线诱发生物遗传基因突变,促进基因重组和核外突变,获得有利用价值的突全体。诱变育种的辐射技术和方法在不断地发展看,辐射源由X射线、γ射线发展到快中子、电子束、空间辐射,离子束诱变育种是近十几年崛起的新技术,具有损伤轻、突变率高、突变谱广的优点,概述了这一新的品种改良技术的进展。     

东北过伐林区四种森林类型的物种多样性比较研究

运用无偏对应分析(DCA)、群落本质多样性排序和方差分析的方法,研究了东北过伐林区吉林省汪清林业局境内的四种森林类型——针阔混交林、阔叶混交林、柞木林和长白落叶松人工林的林分层次的植物物种多样性间的差异。从4种类型下层植被多样性指数的比较结果来看,针阔混交林最高,阔叶混交林和落叶松人工林次之,柞木林最低。最后提出了部分经营建议。     

谷氨酰胺对大剂量顺铂用药后大鼠肠道微生态影响的实验研究

目的 探讨谷氨酰胺( glutamine,Gln)对大剂量顺铂(cisplatin,DDP)用药后大鼠肠道菌群失衡及细菌易位和肠黏膜形态的影响.方法 SD大鼠30只,雌雄各半,依体重随机分为3组:DDP用药组、DDP与Gln联合用药组及生理盐水(NS)对照组,每组10只.10 mg/kg DDP单次腹腔内注射,等量NS腹腔内注射对照;DDP用药前3d开始,联合用药组大鼠Gln 1g/(kg·d)灌胃,等量水灌胃对照.DDP用药后48 h,各组大鼠麻醉后内眦静脉取血测血清尿素氮(BUN)、肌酐(CRE)含量;无菌条件下剖腹取回盲部淋巴结匀浆后细菌培养;取空肠、回肠和结肠段内容物细菌涂片检查肠内菌群比例的变化;取回肠黏膜组织检查形态学改变.结果 DDP用药后48 h,DDP用药组大鼠血BUN和CRE含量明显升高,出现急性肾功能衰竭;黏膜水肿明显、绒毛短缩部分破坏、隐窝变浅;各段肠管内革兰阴性杆菌所占比例较对照明显增高(P＜0.01);回盲部淋巴结革兰阴性菌阳性率为80％,而对照组大鼠回盲部淋巴结无细菌生长.DDP用药后48 h,联合用药组大鼠血BUN和CRE含量略低于DDP用药组大鼠,但仍明显高于对照组大鼠(P＜0.01);大鼠回肠黏膜水肿较DDP用药组大鼠明显减轻、绒毛破坏不明显;回肠内革兰阴性杆菌所占比例明显高于DDP用药组大鼠(P＜0.01),各段肠管内革兰阴性杆菌所占比例亦明显高于对照组大鼠(P＜0.01);回盲部淋巴结革兰阴性菌阳性率为30％,明显低于DDP用药组大鼠.结论 大剂量DDP在引起大鼠急性肾功能衰竭的同时,亦可导致大鼠肠黏膜损伤、肠道内菌群失衡,并出现肠源性细菌易位.Gln具有保护肠黏膜、减少肠源性细菌易位的功能,但对大剂量DDP所致肠道内菌群失衡及急性肾功能衰竭无明显防治作用.     

亲和层析纯化肌质网Ca~（2＋）－ATP酶

建立了一种亲和层析纯化肌质网Ｃａ￣（２＋）－ＡＴＰ酶的方法．用非离子型去污剂Ｃ＿（１２）Ｅ＿８溶解肌质网,再通过反应红－１２０琼脂糖亲和层析柱使肌质网Ｃａ￣（２＋）－ＡＴＰ酶纯度从粗品中的６５％提高到９９％,并具有较高ＡＴＰ水解活性．经ＳＤＳ－聚丙烯酰胺凝胶电泳检测,为电泳纯．     

利用蛋白质组学技术筛选隐球菌作用血管内皮细胞后差异表达蛋白

目的筛选新生隐球菌孵育后血管内皮细胞与正常细胞的差异蛋白质谱。方法利用二维凝胶电泳获得新生隐球菌孵育后血管内皮细胞与正常细胞差异表达蛋白质点,并对部分差异蛋白点进行质谱鉴定分析。结果Peroxiredoxin1及Calpactin I light chain等13个蛋白的表达水平在两组细胞间发生明显改变。结论Peroxiredoxin1及Calpactin I lightchain等蛋白可能参与了新生隐球菌对血管内皮细胞屏障的侵袭过程。     

甘肃泥盆纪头足类的一新属——甘肃角石

本文描述的头足类化石,系韩乃仁于1968年,采自甘肃省宕昌县,位于Stringocephalus层位之上,经研究后定为一新属——甘肃角石Gansuceras gen. nov.;同层位的有腕足类Indospirifer sp.;珊瑚Pseudomicroplasma sp., Temnophyllum sp.,从生物群的面貌来看,时代应为中泥盆世.陈向安帮助鉴定薄片,在此谨致谢意.     

Opening angles and residual strains in normal rat trachea

The no-load state and zero-stress state of the normal rat trachea were analyzed. It was found that there exist compressive residual strains in the inner wall region of the rat trachea and tensile residual strains in the outer wall region. The fact that the opening angle of the rat trachea cut at the cartilaginous region is significantly larger than that cut at the muscular portion shows that residual strains exist mainly in the muscular region in the rat trachea. It was also indicated that the opening angles and residual strains expressed by cutting at the muscular portion are basically identical along longitudinal location and those expressed by cutting in the cartilaginous region tend to increase in the longitudinal direction in the normal rat, and that there exists quantitatively positive correlation between the opening angles and residual strains in rat trachea. The results will help to further understand the opening angles and residual strains in the trachea and study tracheal remodeling in response to mechanical environment.     

跨膜Ca^2＋梯度对肌质网Ca^2＋—ATP酶调节的特异性

我们曾报道跨膜Ｃａ＾２＋梯度可通过膜脂影响肌质网Ｃａ＾２＋－ＡＴＰ酶的构象和活性。本文就跨膜Ｃａ＾２＋－ＡＴＰ酶的构象和活性。本文就跨膜Ｃａ＾２＋梯度对肌质网Ｃａ＾２＋－ＡＴＰ酶的调节是否具有特异性作进一步研究。结果表明这种特异性表现在两方面：一是跨膜Ｃａ＾２＋梯度对肌质网Ｃａ＾２＋－ＡＴＰ酶功能的调节不能归结于跨膜Ｃａ＾２＋深度梯度所导致的膜电位的作用,离子载体ＦＣＣＰ可消除跨膜电位但并不影响肌