生物化学家莱洛伊尔L.F.

著名生化学家莱洛伊尔L.F.(Leloir Luis F.)生于1906年,死于1987年12月4日。他的初期贡献之一且立即引人注目的,是发现了葡萄糖-1,6-二磷酸及葡萄糖-1,6-二磷酸作为磷酸葡萄糖变位酶辅助因子的作用。效仿于此,科里、萨瑟兰和帕斯特纳克一起,提出作为磷酸甘油酸变位酶的2,3双二磷酸甘油酸的类似作用的提议。在莱洛伊尔的重大发     

R. D. Fitzgerald's F. L. S. „Australian Orchids“

Ohne Zusammenfassung     

F.Silvestri教授逝世三十周年

意大利著名昆虫学家F.Silvestri逝世巳经三十年了。我以深切的感情缅怀这位世界昆虫界的一代巨人,中国人民的好朋友。 他五十年前来过中国,爱上了中国,他热情地希望:中国富强,中国人民幸福,科学事业(包括昆虫学)在中国兴旺发达起来。 今天,在以华国锋同志为首的党中央领导下,他老人家这个愿望,也就是全国人民的愿望,已经真正开始实现了！ 愿他安息！他的科学业绩永垂不朽！中意人民之间的友谊万古长青！     

Differentiation of F1 hybrids P. nigra J. F. Arnold × P. sylvestris L., P. nigra J. F. Arnold × P. densiflora Siebold et Zucc., P. nigra J. F. Arnold × P. thunbergiana Franco and their parental species by needle volatile composition

The volatile composition of needles from three F₁ hard pine hybrids produced by the controlled hybridization and their parental species were researched with gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS) in order to explore the utility of terpenes in hybrid identification (their differentiation from the parental species) as well as confirmation of hybridity. The analysed hybrids were: 1. Pinus nigra J. F. Arnold × Pinus sylvestris L. (= nisy), 2. P. nigra × Pinus densiflora Siebold et Zucc. (= nide) and 3. P. nigra × Pinus thunbergiana Franco (= nith). A total of 55 compounds were identified. All identified compounds were terpenes, except trans-2-hexenal.Three analysed F₁ hybrids showed the same qualitative pattern of the needle volatile composition as their parental species. However, there were quantitative differences in several major terpenes. The volatile composition of the needles from the hybrids nisy were equally similar to both parents, the hybrids nide were more similar to the female parent (P. nigra), whereas the hybrids nith were more similar to the male parent (P. thunbergiana). According to the content of germacrene D, as the specific component of P. nigra (female parent of the three analysed F₁ hybrids), all hybrids were intermediary in relation to the parental species. The content of Δ-3-carene (the specific component of P. sylvestris) in the hybrids nisy was also intermediary. The hybrids nide had a higher content of thunbergol (specific component of P. densiflora) than the other analysed hybrids. In view of the content of β-pinene, the specific component of P. thunbergiana, the hybrids nith were intermediary to the parental species and that content was considerably higher than in the other analysed hybrids. The intermediary quality of F₁ hybrids for these specific components in relation to the parental species confirms their hybrid character.The needle volatile composition analysis as well as the previous morphometric analysis confirm the hybrid character of three F₁ hybrids, whose female parent is P. nigra, and male parents are P. sylvestris, P. densiflora, i.e. P. thunbergiana.     

浅谈D.Y.F与CAI的结合运用

素质教育的目标是提高学生全面素质,使他们能够符合当前社会发展的要求,但目前的教学模式是以教师教为主（即注入式教学）,无法充分发挥学生的主体作用。ＤＹＦ（定向质疑———引导探索———反馈运用）是吉林市教育学院为了克服传统教学的弊端,变教师满堂灌为以...     

浅谈D.Y.F与CAI的结合运用

Ｄ．Ｙ．Ｆ（定向反馈—引导探索—反馈运用）是吉林市教育学院以科学方法为指导,以教育心理学为理论基础,在传统教学经验的基础上,设计的一种课堂教学类型。ＣＡＩ（计算机辅助教学）则是以计算机为媒介,通过学生与计算机之间的交互作用来达到教学目的的一种现代化教...     

Il Trentesimo Anniversario della Morte del Prof. F. Silvestri

Il famoso entomologo italiano, mio maestro F. Silvestri e' gia' scomparso trent'anni. Io ricordo con un profondo sentimento a porpetua memoria di questo grand'uomo dell' epoca in campo entomologico, boun amico del popolo cinese. Nei cinquantacinque anni precedenti, egli venne in Cina e amava la Cina, eglisperava affettuosamente che la Cina potrebbe diventare uno stato ricco e forte, ilpopolo cinese potrebbe vivere felicemente, e le scienze cinesi (include anche la ento-     

Cunxi Wang · Kevan P.C. Croft · David F. Hildebrand

 Auxin [α-naphthaleneacetic acid (NAA) or indole-3-acetic acid] can induce the expression of lipoxygenases (LOXs) in cultured immature zygotic embryo cotyledons of soybean [Glycine max. (L.) Merr]. These auxin-induced LOXs are different from those normally expressed in seeds but have the same isoelectric points (pI) as those found in seedlings. The pIs of the two seedling LOXs were determined to be 5.09 and 5.23. One of the auxin-induced LOXs has the same pI (5.09) and molecular mass (94 kDa) as seedling LOX4. The partial amino acid sequences from the purified NAA-induced pI-5.09 LOX are identical to those of LOX4. RNA protection assays showed that NAA induces the expression of LOX4 and LOX5 mRNAs in cultured embryo cotyledons where they are not normally expressed. Soybean genotypes with a polymorphic variant of LOX4 in hypocotyls showed the same variation as NAA-induced LOXs in the embryo cotyledons. These results demonstrate that the NAA-induced pI-5.09 LOX is seedling LOX4 and also suggest that auxin might be directly or indirectly involved in seedling LOX expression during seed germination. Received: 10 January 2000 / Revision received: 16 June 2000 / Accepted: 29 June 2000     

关于国际遗传学联合会(I.G.F.)介绍

据国际遗传学联合会章程介绍,I.G.F.的宗旨是:促进全世界遗传学家之间的了解、合作和友谊;筹划和资助国际和地区性遗传学会议以及专题讨论会;与其它有关的国际组织保持联系并促进遗传学研究领域内的国际合作;互通情报;组织著名遗传家的访问等,借以促进遗传学的发展。     

Characterisation of New Zealand Fusarium populations using a polyphasic approach differentiates the F. avenaceum/F. acuminatum/F. tricinctum species complex in cereal and grassland systems

The purpose of this study was to determine the diversity and prevalence of Fusarium species in a survey of cereal and grassland systems from the South Island of New Zealand by applying morphological and molecular techniques. Isolates were collected from soil, roots, and stems from 21 cereal and grassland sites. Ten Fusarium species were identified using morphological characters, including F. acuminatum, F. avenaceum, F. crookwellense, F. culmorum, F. equiseti, F. oxysporum, F. poae, F. pseudograminearum, F. sambucinum, and F. tricinctum. In general, their distribution was found to be unrelated to biogeographical location, although agricultural practice increased the overall diversity of Fusarium. Phylogenetic analyses were successfully used to identify morphologically similar isolates belonging to the F. avenaceum/F. acuminatum/F. tricinctum species complex and to resolve previously undetermined relationships amongst these species. Fifty-eight isolates classified as either F. avenaceum, F. acuminatum, or other closely related species as well as several well-characterised isolates from international culture collections were examined using DNA sequence data for β-tubulin (βTUB), translation elongation factor 1α (EF1α), and mitochondrial small subunit ribosomal RNA (mtSSU). Analyses of DNA sequence data from both βTUB and EF1α discriminated among isolates of F. avenaceum, F. acuminatum, and F. tricinctum and determined that these three distinct sequence groups formed a single clade. By contrast, mtSSU was unable to differentiate F. avenaceum from F. acuminatum and other closely related species believed to be F. tricinctum. Comparison of the EF1α sequences with the international FUSARIUM-ID database supported the identification of isolates in this study. As in other studies, F. avenaceum was found to be widespread in agricultural and native ecosystems. However, F. acuminatum in New Zealand was found only on non-wheat hosts. The reason for the absence of this wheat pathogen in cereal-based ecosystems in New Zealand remains unknown.     

Meadow fescue: Festuca elatior L. or F. pratensis Hudson?

The grass commonly called “meadow fescue” is known in the United States asFestuca elatior L. and in Europe asF. pratensis Hudson. Study of the literature and type specimen shows that the nameF. elatior L. is ambiguous and confused. The earliest correctly applied name isF. pratensis Hudson, hence it should be universally adopted.     

Effects of tissue extract of adults on metamorphosis in Ascidia mentula O.F. Müller and Ascidiella scabra (O.F. Müller)

Unhatched, but fully developed larvae of two solitary ascidians Ascidia mentula O.F. Müller and Ascidiella scabra (O.F. Müller) were incubated in a variety of adult tissue extracts, which an earlier study had shown to accelerate metamorphosis. Our study confirmed this observation and showed, furthermore, that tissue extracts induce tail resorption in unhatched larvae of Ascidiella. For both species, the most active induction of metamorphosis was obtained with tunic tissue extracts. The results indicate that chemical stimulation without the presence of tactile cues may initiate metamorphosis. We suggest that the ability of tunic extracts to induce metamorphosis may explain juvenile establishment on adult ascidians and their aggregated distribution found in nature.