高粱对丝黑穗病的抗性及遗传研究

1981—1985年在人工接种的条件下,对1239份高粱品种资源,进行了抗丝黑穗病性鉴定。与此同时,用17个抗性不同的品种系,按照不完全双列杂交设计,进行了高粱对丝黑穗病的抗性遗传研究。结果表明,高粱对丝黑穗病的抗性遗传方式因品种而异。有的品种系具数量性状遗传特点,有的则具有质量性状遗传特点。抗病性属数量性状遗传的品种系,其抗性主要是受加性基因控制。     

应用蛋白印迹法检测鼻咽癌病人血清中抗Epstein—Barr病毒IgA/EA抗体

曾毅等建立了一系列检测EB病毒IgA/VCA和IgA/EA抗体的鼻咽癌早期诊断方法,取得了满意的结果。为了进一步提高对鼻咽癌诊断更为特异的IgA/EA抗体的检出率,我们建立了检测EB病毒IgA/EA抗体的蛋白印迹法。方法敏感特异,结果令人满意。 本法中所用的两个质粒系由本实验室与西德Pettenkofer研究所Wolf教授的实验室合作构建。pUCARG1140和pUC9MBcE3.2质粒均为表达质粒,前者携带着来源于EB病毒Bam     

鼻蝇亚科分族的探讨并记二新种(双翅目:丽蝇科)

鼻蝇亚科(Rhiniinae)是双翅目丽蝇科(Calliphoridae)中比较特殊的一大类群,因此也有人把它从丽蝇科分出,独立成科的。其特征有口上片突出如鼻状,后头上部大半是裸出的,约占整个头的宽度的范围内连粉被也缺如;r脉的上方沿后侧有一列明晰的小刚毛,翅下大结节上无立纤毛,下腋瓣裸。主要分布在东洋区、非洲区、大洋洲区以及古北区南缘。目前全世界已知有22个属,近300种,曾有报道其幼虫寄生于白蚁巢内及蝗     

Culture and characterization of dental follicle cells from rat molars

Summary Because the dental follicle is necessary for the eruption of teeth of limited eruption, it was the objective of this study to determine if the cells of the follicle could be cultured in vitro. To achieve this, dental follicles and associated enamel organs were dissected from the first and second mandibular molars of 6–7-day-old rats (secretory stage of amelogenesis), and then cultured in a medium that promotes fibroblast growth — the predominant cell type of the dental follicle. The cultured cells grew to confluency and were kept through 3 passages before experimentation. The cultured cells were fibroblastic in shape, elongate with processes, and transmission electron microscopy revealed that they contained an abundant rough endoplasmic reticulum, but did not form desmosomes. Immunofluorescent staining for anti-vimentin showed that all the cells stained and electron-microscopic immunogold labeling indicated that the antibody was associated with intermediate filaments. As revealed by SDS-polyacrylamide gel electrophoresis and Western blotting, the cultured cells synthesized and secreted the extracellular matrix molecules fibronectin and procollagens. Subsequent immunofluorescence staining of permeabilized and non-permeabilized cells confirmed the presence of fibronectin and type I collagen both intra- and extracellularly. Thus, based on all the above characteristics, the cultured cells appeared to be fibroblasts derived from the dental follicle, although a few of the fibroblasts may be derived from undifferentiated mesenchymal cells interposed between the alveolar bone and follicle. Experiments now can be conducted to determine how these cultured cells respond directly to growth factors that alter the rates of tooth eruption.     

鹅掌楸种子和胚胎发育的研究

应用控制授粉、软 X-射线法、常规石蜡制片法和荧光检测等手段,研究了鹅掌楸(Lirio-dendron chinense(Hemsl.)Sarg.胚胎发育和控制授粉与结籽率的相关性。控制授粉后2小时花粉萌发,6小时萌发率最高,柱头可授期持续30小时左右。花粉管借助于柱头毛之间的分泌物进入柱头沟,经花柱沟、珠孔塞和珠心冠原进入胚囊,行珠孔受精。授粉后2周,胚乳为2至3细胞厚的狭组织;第6周,胚乳充满胚囊腔,珠心随之解体殆尽;第7到8周,球形胚、心形胚发生;第14到16周,子叶形成;第22周种子或熟,胚乳丰富。单株自然授粉结籽率不足1%。控制授粉后,单个聚合果的最高结籽率可达39%,9个聚合果的平均结籽率为17.7%。     

咽喉部高频喷射通气调节各参数对狗肺通气效率的影响

用相关和回归处理方法,研究了8条正常狗咽喉部高频喷射通气时,调节驱动压、呼吸比和频率对喷气量、吸入气氧浓度、动脉血气及气道内压的作用。结果显示,驱动压和呼吸此对各观察指标几乎有同等重要的作用,频率的影响很小,喷气量与吸入气氧浓度、动脉血气、气道内压间存在显著的正相关关系。说明调节参数的意义主要在于改变了喷气量。     

The rate of nuclear cytoplasmic protein transport is determined by the casein kinase II site flanking the nuclear localization sequence of the SV40 T-antigen.

We have previously demonstrated [Rihs, H.-P. and Peters, R. (1989) EMBO J., 8, 1479-1484] that the nuclear transport of recombinant proteins in which short fragments of the SV40 T-antigen are fused to the amino terminus of Escherichia coli beta-galactosidase is dependent on both the nuclear localization sequence (NLS, T-antigen residues 126-132) and a phosphorylation-site-containing sequence (T-antigen residues 111-125). While the NLS determines the specificity, the rate of transport is controlled by the phosphorylation-site-containing sequence. The present study furthers this observation and examines the role of the various phosphorylation sites. Purified, fluorescently labeled recombinant proteins were injected into the cytoplasm of Vero or hepatoma (HTC) cells and the kinetics of nuclear transport measured by laser microfluorimetry. By replacing serine and threonine residues known to be phosphorylated in vivo, we identified the casein kinase II (CK-II) site S111/S112 to be the determining factor in the enhancement of the transport. Either of the residues 111 or 112 was sufficient to elicit the maximum transport enhancement. The other phosphorylation sites (S120, S123, T124) had no influence on the transport rate. Examination of the literature suggested that many proteins harboring a nuclear localization sequence also contain putative CK-II sites at a distance of approximately 10-30 amino acid residues from the NLS. CK-II has been previously implicated in the transmission of growth signals to the nucleus. Our results suggest that CK-II may exert this role by controlling the rate of nuclear protein transport.     

激光、血卟啉对肿瘤细胞DNA单链断裂及其重接的影响

用简化的Kohn氏碱洗脱法,观察了光敏剂血卟啉衍生物(HPD)对小鼠S-180肿瘤细胞DNA单链断裂及其重接修复的影响。激光HPD能导致S-180细胞DNA单链断裂明显增加,而且这种断裂随着保温时间的延长,继续增多。在本实验条件下没有观察到HPD对X线的增敏作用,HPD不能增加X线所致的DNA单链断裂,也不能影响其重接。单链断裂重接动力学的实验进一步证明了这个论点。     

Generation of a recombinant Moloney murine leukemia virus carrying the v-src gene of avian sarcoma virus: transformation in vitro and pathogenesis in vivo.

A Moloney murine leukemia virus (M-MuLV) recombinant carrying the v-src gene of avian sarcoma virus was generated by the introduction of a cloned portion of v-src from Schmidt-Ruppin A avian sarcoma virus into a molecular clone of M-MuLV provirus at the recombinant DNA level. The v-src sequences (lacking a portion of the 5' end of v-src) were inserted into the p30 region of the M-MulV gag gene so that M-MuLV gag and v-src were in the same reading frame. Transfection of this chimeric clone, pMLV(src), into NIH 3T3 cells which were constitutively producing M-MuLV gag and pol protein resulted in the formation of foci of transformed cells. Infectious and transforming virus could be recovered from the transformed cells. This virus was designated M-MuLV(src). M-MuLV(src)-transformed cells contained two novel proteins of 78 and 90 kilodaltons. The 78-kilodalton protein, p78gag-src, contained both gag and src determinants, exhibited kinase activity in an immune kinase assay, and is probably a fusion of Pr65gag and src. The 90-kilodalton protein, which is of the appropriate size to be the gPr80gag fused to src, contained gag determinants as well as a V8 protease cleavage fragment typical of the carboxy terminus of avian sarcoma virus pp60src. However, it could not be immunoprecipitated with an anti-v-src serum. M-MuLV(src)-transformed cells showed elevated levels of intracellular phosphotyrosine in proteins, although the elevation was intermediate compared with cells transformed with wild-type v-src. M-MuLV and amphotropic murine leukemia virus pseudotypes of M-MuLV(src) were inoculated into newborn NIH Swiss mice. Inoculated mice developed solid tumors at the site of inoculation after 3 to 6 weeks, with most animals dying by 14 weeks. Histopathological analysis indicated that the solid tumors were mesenchymally derived fibrosarcomas that were both invasive and metastatic.