一个恢复力受单基因控制的水稻CMS育性回复突变体

利用￣（６０）Ｃｏ－γ射线对具有印尼水田谷细胞质的籼稻细胞质雄性不育系Ⅱ－３２Ａ干种子进行诱变处理,获得了一育性回复突变体Ｔ２４。育性基因未纯合的突变体分离出可育株和完全不育株,比例为３∶１;其与Ⅱ－３２Ａ和珍汕９７Ａ测交,Ｆ１代分离出１∶１的可育株和不育株。育性稳定株系与Ⅱ－３２Ａ和珍汕９７Ａ杂交,Ｆ２分离成３∶１的可育株和不育株。表明其育性回复是由一对基因显性突变所致。这一突变体对不育系的育性恢复机制不同于明恢６３、２０９６４等恢复系,后者表现为两对显性恢复基因作用。未观察到Ｔ２４与亲本Ⅱ－３２Ａ除育性以外的其他性状的差异,因而两者构成育性恢复基因的近等基因系。本文还对不育系育性回复类型和Ｔ２４的理论意义与育种价值进行了讨论。     

三系和二系籼粳交杂种F1农艺性状遗传表现的比较

通过6个籼型三系不育系（A）和3个籼型光温敏核不育系（S）分别与7个粳型广亲和系（W）的不完全双列杂交试验,对两类不同配组模式（即AW和SW）的杂种优势的表现、农艺性状遗传特点及参试亲本基因效应值的差异进行了比较,结果表明,在多数性状上,AW比SW型具有更强的群体平均优势和群体超亲优势;而两者农艺性状遗传方差分量除主穗总粒数等外,在抽穗期、着粒密度和剑叶长的遗传分量则较为一致;参试亲本的加性效应预测值,是D汕A具有降低株高的效应,红突A、W6llls和浙南1号A具有明显地缩短生育期的效应,红突A、D汕A和协青早A有显著地增加每株穗数的效应,而02428、T984和轮回422则有增加主穗总粒数的效应．     

家兔胫骨前肌肌纤维型的分布研究

根据家兔胫骨前肌的肌纤维起止、排列和神经支配特征,将该肌分为前、后两个亚体。利用家兔８例１６侧胫骨前肌,按上述两个亚体分别取材,作恒冷箱冰冻横切,肌球蛋白ＡＴＰ酶染色,将肌纤维分为Ⅰ型、ⅡＡ型、ⅡＢ型,检测各亚体的肌纤维型构成比例,肌束内肌纤维的分布特征,并用图象分析仪测量各亚体肌纤维横切面积和直径。结果发现,前、后亚体以Ⅱ型纤维居多,前亚体ⅡＡ型纤维高达３５．４％,后亚体Ⅰ型纤维多达２４．５％,两者的ⅡＢ型纤维均达５０％左右。而左、右侧之间无差异,肌束周边部内Ⅰ型纤维仅占１２．７～１３．３％,ⅡＢ型纤维高达５９．９～６０．０％,说明受肌束膜压迫影响,ⅡＢ型肌纤维血供少,以适应无氧酵解的功能。各亚体的Ⅰ型纤维较细,Ⅱ型纤维较Ⅱ粗,Ａ型与ⅡＢ型二者相似。作者认为,前亚体主要参与快速有力的足背屈运动,后亚体则维持踝关节的稳定,保持足弓的形状和弹性,以便适应该肌的站立、跑动和跳跃的功能。     

丹参酮Ⅱ－A磺酸钠对鼠肝线粒体功能的影响

利用大鼠肝脏线粒体为材料,以琥珀酸为底物,研究了不同浓度的丹参酮Ⅱ－Ａ磺酸钠对线粒体态４、态３呼吸及呼吸控制率,线粒体跨膜电位,线粒体呼吸链复合体（Ⅱ＋Ⅲ）电子传递及质子转移活性的影响。结果证明丹参酮ⅡＡ－磺酸钠是线粒体呼吸链复合体（Ⅱ＋Ⅲ）的有效抑制剂。文中对丹参酮ⅡＡ－磺酸钠在心肌缺血再灌注过程中的保护作用的分子机理进行了讨论。     

汉防己甲素及克矽平对矽肺大鼠Ⅰ型和Ⅲ型胶原mRNA的影响

汉防己甲素（汉甲）及克矽平（Ｐｏｌｙｖｉｎｙｌｐｙｒｉｄｉｎｅ－Ｎ－Ｏｘｉｄｅ,ＰＶＮＯ）是目前较为有效的抑制矽肺纤维化的药物。本文研究了其对胶原ｍＲＮＡ水平的影响．斑点杂交实验表明大鼠接尘６０天和１２０天后α１（Ⅰ）及α１（Ⅲ）ｍＲＮＡ水平明显上升,经汉甲或克矽平治疗１个月或３个月后,胶原ｍＲＮＡ水平明显下降。原位杂交结果表明胶原ｍＲ－ＮＡ银颗粒与细胞性结节和增厚的肺泡壁的成纤维细胞分布重合。汉甲或克矽平治疗后银颗粒数下降。提示汉甲及克矽平对矽肺进程中的胶原基因表达增强有抑制作用。     

An improved method for the isolation of type II and clara cells from mice

Identifying the causal events and temporal aspects of lung cancer development requires the ability to isolate target and nontarget cells for comparative analyses. Current methodology can either isolate only one pure specific cell population from a lung or multiple cell types at lower purity. Previous studies in our laboratory have identified the alveolar type II cell as the progenitor cell for tumor development in the A/J mouse. The purpose of this study was to develop new protocols for the isolation and culture of type II and Clara cells from the mouse lung. Both type II and Clara cells were obtained in high purity using a sequential centrifugal elutriation protocol. In the first elutriation, cell fractions were collected using a Standard chamber. The type II and Clara cell fractions were then elutriated separately (two different separations) using a Sanderson chamber. The final purity of the type II and Clara cell preparations was 73% and 76%, respectively. Colonies of 4 to 20 Clara cells exhibiting epithelial morphology were evident 1 wk after plating in low serum medium. The growth of type II cells required the addition of bronchioalveolar lavage fluid and acidic fibroblast growth factor to the medium. The isolation of viable mouse type II and Clara cells in high purity should facilitate the identification of cell-specific changes in gene expressions or in enzymatic pathways following in vivo or in vitro exposure to environmental carcinogens.     

The impact of type I diabetes on rat liver γ-glutamyltranspeptidase

The impact of type 1 diabetes mellitus on liver -glutamyltranspeptidase, a premalignant marker, was studied. Diabetes was induced in male Sprague Dawley and Fischer 344 rats by administration of Streptozotocin, which produced a stable and moderately severe diabetic state. In liver homogenates, -glutamyltranspeptidase was increased over control levels: 1.2, 8.1 and 13,2 fold in Strague-Dawley rats; 4.8, 58.4 and 84.7 fold in Fischer 344 rats; at 1, 3 and 6 weeks following Streptozotocin treatment. In plasma membranes isolated from the livers of Fischer 344 rats, -glutamyltranspeptidase was increased over control levels: 5.6, 75 and 127 fold at weeks 1, 3 and 6 following Streptozotocin treatment. The relative specific activity of 5-nuleohdase was found to be similar: 9–14, indicating comparable degrees of plasma membrane purity. Plasma glutamate-pyruvate transaminase levels were minimally and similarly affected at all time points indicating lack of association of increasing -glutamyltranspeptidase activity with overt liver damage. Thyroid hormone replacement, with both T₃ (0.6 g/Kg) once a day and T₄ (6.0 g/kg) twice a day for three days elicited a further 30% increment in enzyme activity. Insulin replacement (20–40 units/200 g body weight) twice a day for five days reduced enzyme activity 51% at week 6. This was associated with an increase in -glutamyltranspeptidase in the plasma from 14 fold over control levels in the diabetic state at week 6 to 53 fold ever control levels after insulin replacement at week 6. It is proposed that the diabetes-induced increase in -glutamyltranspeptidase is reduced by an insulin-directed shedding of the enzyme into the plasma.     

Basement membrane components of bronchial epithelium in humans suffering from chronic nonspecific lung diseases

Collagen IV and laminin are important constituents of the basement membrane (BM). By use of immunocytochemistry we examined the occurrence and distribution of these two components in the BM beneath normal, mucoid and metaplastic epithelium of large bronchi in 22 adults suffering from chronic nonspecific lung diseases. Both collagen IV and laminin were expressed as a thin and continuous layer beneath the epithelium in most tissue specimens with normal epithelium. In a few specimens the layer showed interruptions with a patchy distribution of the immunoreactivity. Three patterns of distribution of BM components were found under the metaplastic epithelium. Total absence of immunoreactive collagen IV and laminin was the most common variant. Weak and scarce staining for both proteins in the BM characterized the second pattern. The third variant showed strong collagen IV immunoreactivity but lack of laminin. The BM beneath the mucoid epithelium was characterized by irregular distribution of collagen IV and laminin. We suggest that the occurrence and distributional pattern of the BM components are related to the type of overlying epithelium and connected with an altered synthesis of these components.     

Classification of cultivated rices into indica and japonica types by the isozyme,RFLP and two milled-rice methods

Four methods for classifying cultivated rices (Oryza sativa L.) (including IR varieties) into indica and japonica types — waxy gene product in endosperm starch, glutelin ₃ molecular weight in milled rice, RFLP polymorphism at the Wx locus and Glaszmann's isozyme method — were compared. On the basis of the two endosperm traits and the RFLP method Glaszmann's group 1 (indica) was classified as mainly indica and intermediate groups 2, 3 and 4 as exclusively indica. However, the endosperm traits classified Glaszmann's group 5 as mainly indica, while the RFLP method classified it as japonica. The RFLP waxy gene probe was closest to the isozyme method in classifying group 6 as japonicas; the waxy gene product gave mainly indica reaction even in group 6, and the glutelin ₃ method was intermediate. All IR rices were classified as being indica on the basis of Wx gene product and by Glaszmann's method, but a few were classified as japonica by the glutelin ₃ method and by the RFLP waxy gene probe.     

Streptococcal erythrogenic toxin type C is not a phosphorylated protein. Description of two different purification procedures and investigation of its phosphorylation state

Abstract Erythrogenic toxin type C (ETC) from different streptococcal group A strains was successively purified by absorption on phenylsepharose, acidic dialysis of the eluate at 40% saturated ammonium sulphate solution, CM-Sepharose chromatography, finally by immunoaffinity chromatography on monoclonal antibodies. Second, after growing of bacteria in the presence of [³²P]orthophosphate to phosphorylate ETC, the ETC was purified with phenylsepharose following immunoaffinity chromatography. The occurrence of phosphoamino acids in the purified ETC was investigated by an immunoassay. No phosphoamino acids could be detected in the ETC molecule. Also after radiolabelling with ³²P it was not possible to demonstrate a radioactive signal. The treatment with alkaline phosphatase has no influence on the mitogenicity or position of ETC in isoelectric focusing. The results obtained led to the conclusion that in contrast to the literature, ETC is not a phosphorylated protein.