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31.
Maria de Fatima Bonaldo Pierre Jelenc Long Su Lee Lawton M. -T. Wu Dorothy Warburton Marcelo Bento Soares 《Human genetics》1996,97(4):441-452
A study was conducted on the feasibility of isolating genes and pseudogenes that map to chromosome 13 by a hybridization-based approach using a 13-specific library and pools of repeat-free cDNA clones. Five pairs of cDNA and chromosome 13 genomic clones were identified and characterized. Partial or full-length sequence was derived from all cDNAs, and database searches were performed for putative gene identification. Partial sequence was also obtained from the chromosome 13 genomic clones for comparison with those of the hybridizing cDNAs. As a result of these analyses we identified three genes, a putative homologue of a porcine mRNA encoding an unidentified hepatic protein, a putative homologue of a yeast integral membrane protein, and a gene for a translationally controlled tumor protein, and two processed pseudogenes, ribosomal proteins L23a and S3a. The latter was formerly identified as the v-fos transformation effector gene, Fte-1, and recently cited as a possible candidate for the BRCA2 gene on chromosome 13. All genes and pseudogenes were localized to cytogenetic bands by in situ hybridization of metaphase chromosomes with probes derived from the chromosome 13 genomic clones. 相似文献
32.
把从榛木(Corylusavellana L.)花粉中分离得到的高尔基囊泡与经高度纯化并聚合好的牛脑微管进行体外组合,然后于1.5 m ol/L的蔗糖层上进行超离心,对其沉淀物进行SDS-聚丙烯酰胺凝胶电泳和电镜负染。结果表明,花粉高尔基囊泡可以结合到牛脑微管上,证明植物花粉的高尔基囊泡与动物细胞的某些细胞器一样,也与细胞骨架的主要组成之一——微管具有结构上的紧密联系。花粉高尔基囊泡与牛脑微管的体外结合能力,受10 m m ol/LATP和0.5 m ol/LKCl的影响,但不受5 m m ol/L AMP-PNP的影响,说明两者结合可能是通过高尔基囊泡表面与ATP有关的某种外周膜蛋白来完成的。 相似文献
33.
The maximum quantum yields (a,c) for CO2 uptake in low-oxygen atmospheres were determined for 11 species of C3 vascular plants of diverse taxa, habitat and life form using an Ulbricht-sphere leaf chamber. Comparisons were also made between tissues of varied age within species. The species examined were Psilotum nudum (L.) P. Beauv., Davallia bullata Wall. ex Hook., Cycas revoluta Thunb., Araucaria heterophylla (Salisb.) Franco, Picea abies (L.) Karst., Nerium oleander L., Ruellia humilis Nutt., Pilea microphylla (L.) Karst., Beaucarnea stricta Lem., Oplismenus hirtellus (L.) P. Beauv. and Poa annua L. Quantum yields were calculated from the initial slopes of the response of CO2 uptake to the quantity of photons absorbed in conditions of diffuse lighting. Regression analysis of variance of the initial slopes of the response of CO2 uptake to photon absorption failed to show any statistically significant differences between age classes within species or between the mature photosynthetic organs of different species. The constancy of a,c was apparent despite marked variation in the light-saturated rates of CO2 uptake within and between species. The mean a,c was 0.093±0.003 for 11 species. By contrast, surface absorptance varied markedly between species from 0.90 to 0.60, producing proportional variation in the quantum yield calculated on an incidentlight basis. The ratio of variable to maximum fluorescence emission at 695 nm for the same tissues also failed to show any statistically significant variation between species, with a mean of 0.838±0.008. Mean values of a,c reported here for C3 species, in the absence of photorespiration, are higher than reported in previous surveys of vascular plants, but consistent with recent estimates of the quantum yields of O2 evolution.Abbreviations and Symbols A
rate of CO2 uptake per unit projected area (mol · m–2 · s–1)
- Fm
the maximum fluorescence emission at 695 nm in saturating excitation light when closure of PSII reaction centres is maximal (relative units)
- Fo
the ground fluorescence at 695 nm when all PSII reaction centres are assumed open (relative units)
- Fv
the difference between Fm and Fo
- JQ
rate of CO2 uptake by the sample (nmol · s–1)
- JQ
rate of photon absorption by the sample (nmol · s–1)
- Q
absorbed photon flux per unit of projected area (nmol · m–2 · s–1)
- 1
the light absorptance of photosynthetic organs (dimensionless)
- s1 and s'1
the total and projected surface areas of the photosynthetic organs examined (m2)
- a,c and i,c
the quantum yields for CO2 uptake on an absorbed- and incident-light basis, respectively (dimensionless)
- a,o
the quantum yield for O2 evolution on an absorbed-light basis (dimensionless)
This work was supported by grant PI7179-BIO, FWF, Austria to H.B-N. and by a British Council travel award to S.P.L. This work was completed under the auspices of U.S. Department of Energy under Contract No. DE-AC02-76CH00016. We also thank Dr. K.J. Parkinson of PP Systems, Hitchin, UK for the loan of a prototype of a commercial integrating-sphere leaf chamber developed from our design. 相似文献
34.
本文以临床体征,胸片和连续二次以上细菌培养阳性为诊断标准,报告革兰阴性杆菌肺炎23例,并就其临床表现,并发症及预后进行分析,提出8种情况应考虑革兰阴性杆菌肺炎,对临床诊断和治疗有指导意义. 相似文献
35.
36.
Somatic embryos and adventitious shoots were initiated from immature cotyledons 10–14 weeks after anthesis. Maximum embryogenesis occurred 12 weeks after anthesis and maximum shoot organogenesis occurred 14 weeks after anthesis. The best treatment for induction of somatic embryos and adventitious shoots from immature cotyledon explants was on agar-solidified WPM supplemented with 0.1 M 2,4-D and 5.0 M TDZ and incubated in light for the first four weeks. Rooting of adventitious shoots was best if they were quickdipped in 2.5 mM IBA and 1.25 mM NAA in 1% dimethyl formamide and 3.9% ethanol (120 Wood's Rooting Compound: water, by volume). Plantlets from rooted adventitious shoots were acclimatized to the greenhouse.Abbreviations BA
Benzyladenine
- 2,4-D
2,4-dichlorophenoxyacetic acid
- DKW
Driver and Kuniyuki (1984) walnut medium
- IBA
indolebutyric acid
- LP
Long and Preece medium described herein
- NAA
naphthaleneacetic acid
- PPF
photosynthetic photon flux
- TDZ
thidiazuron
- WPM
Woody Plant Medium of Lloyd and McCown (1980) 相似文献
37.
Summary Single and multiple Clostridium acetobutylicum P262 sporulation, clostridial stage, granulose, capsule and solvent producing mutants were isolated. Although common regulatory components were involved in the regulation of these events, each individual pathway was able to function independently of each other. Inhibitors of DNA replication inhibited spore formation but did not affect solvent, clostridial stage, granulose and capsule production. 相似文献
38.
Inhibition by heparin-modulated antithrombin III of amidolysis catalysed by m beta-acrosin. 下载免费PDF全文
Purified m beta-acrosin catalysed amidolysis of several p-nitroanilides with C-terminal arginine residues. Antithrombin III inhibited amidolysis catalysed by the enzyme. This effect of antithrombin III was potentiated by heparin, and to a modest extent by heparan sulphate, cellulose sulphate, dextran sulphate and xylan sulphate. De-N-sulphated heparin, de-N-sulphated N-acetylated heparin, heparin of low relative molecular mass, chondroitin 4-sulphate, chondroitin 6-sulphate, dermatan sulphate and hyaluronic acid were ineffective. 相似文献
39.
Susan Orpett Long 《Culture, medicine and psychiatry》1984,8(2):141-163
Both by the standards of American nurses and in the eyes of the Japanese public, nurses in Japan appear subservient. In this paper I explore this situation from three perspectives. Most Japanese nurses lack a sense of professionalism which the nursing elite in Japan as well as sociological theory attributes to the low educational levels of the nurses. The second perspective investigates the nurses' functional role as intermediary between the medical world and the many patients who regard physicians as socially distant. Thirdly, Japanese nurses might be considered the housewives of the hospital in terms not only of their physical duties but also of their caretaking role. If the housewife analogy holds, the values, behavior, and attitudes that give Japanese housewives their satisfaction and their autonomy would considerably alter the role of the nurse in the delivery of cosmopolitan medical care. 相似文献
40.
The effects of ACTH, its o-nitrophenyl sulfenyl derivative (NPS-ACTH) and dibutyryl cyclic AMP (dbc AMP) on the ultrastructural morphology of adrenocortical cells of adult rats in monolayer culture have been investigated. NPS-ACTH, which has previously been shown to stimulate steroidogenesis but not cAMP synthesis in adrenal cells, induced the same characteristic transformation of mitochondrial architecture as produced by ACTH or high concentrations of dbcAMP. All three agents caused the disappearance of electron-opaque granules present in the mitochondria of unstimulated cells. It was found that these granules could be extracted with EGTA (ethylene glycol-bis(beta-aminoethyl ether) N,N,N',N'-tetraacetate). These results are discussed in the light of the known importance of calcium ions in the actions of ACTH. 相似文献