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1.
水稻品质遗传育种研究进展与发展趋势探讨   总被引:5,自引:0,他引:5  
针对国内外水稻优质育种的现状 ;对香味、蒸煮、食味、营养、外观和碾磨品质 ,稻米理化特性、稻米质地特性和水稻淀粉粘滞谱特性等各项品质指标的遗传、基因效应、相互关系等进行了较为详细的比较分析 ;讨论了有关的分子生物学和基因的研究进展 ;介绍了近年来新的稻米品质研究技术及其理论发展。未来水稻育种将向着优质和具有营养保健功能的方向发展。需要重视新功能基因的克隆和利用、新基因资源的发掘和利用以及稻米评价技术体系的创新等研究工作。  相似文献   

2.
The hypothesis of a qualitative new field permits the prediction of a new fundamental constant. With this constant a relation between c and h can be found. The new constant permits not only a system of physics but also a new transition from physics into biology.  相似文献   

3.
In anticipation of the publication of full revisions, a diagnosis of a new species of Droguetia is presented together with two new combinations for subspecies of Droguetia iners , a new combination for a species and a variety on Didymodoxa and a new combination for a subspecies of Australina pusilla . The name Elatostema trinerve Hochst. (1845) is shown to be conspecific with and antedate Urera cameroonensis Wedd. (1869). The new combination Urera trinervis is therefore made.  相似文献   

4.
To determine the prevalence and distribution of rickettsial pathogens around the world, scientists have relied more and more upon molecular techniques in addition to serological and culture methods. The ease of use and sensitivity/specificity of molecular techniques such as quantitative real-time PCR assays and multilocus sequence typing have lead to an increase in reports of the detection and identification of new and old rickettsiae in previously known and in new endemic regions. These assays have been successfully used with clinical samples such as serum, blood, and tissue biopsies and with environmental samples such as arthropod vectors including ticks, fleas, lice, and mites, and blood and tissue specimens from small mammal collections and from wild and domestic large animals. These methods have lead to the detection of new and old rickettsial pathogens often in new locations leading investigators to suggest new regions of risk of these rickettsioses.  相似文献   

5.
微生物与能源的可持续开发   总被引:1,自引:0,他引:1  
张薇  李鱼  黄国和 《微生物学通报》2008,35(9):1472-1478
微生物技术在新能源开发领域中有广阔的应用潜力,对能源的可持续发展具有重要的理论和现实意义.简要叙述了生物柴油、燃料酒精、生物制沼气、生物制氢和微生物电池等新能源的原理、优缺点和开发现状,概述了微生物资源在能源领域的应用,指出发掘新的微生物资源或构建工程菌株、明确微生物作用机理、开发新工艺将会是今后研究的重点.  相似文献   

6.
Thermophilic and halophilic extremophiles.   总被引:6,自引:0,他引:6  
The microbiology of extremely hot or saline habitats is a fast moving field with many new successes in the enrichment and isolation of new organisms and in an understanding of molecular factors that impart stability on thermostable and halophilic biomolecules. The results of these studies have shed new light on our understanding of prokaryotic diversity and structural biochemistry.  相似文献   

7.
de Carvalho AA  Hennen JF 《Mycologia》2010,102(5):1096-1113
Ten new teleomorphic species, two status novus taxa and two new combinations in the genus Prospodium are established. The following anamorphs, all closely related to the genus Prospodium, also are proposed: the genus Canasta, its two new species and a new combination, three new combinations for the genus Uredo.  相似文献   

8.
The potential for second-hand markets to reduce demand for new goods is investigated. Using a variant of an economic model originally developed by Anderson and Ginsburgh, the physical implications for material use are explored. The second-hand market grows if transaction costs decrease or if product lifetime increases. In this model, growth of the secondhand market reduces demand for new goods if there are waste used goods that can be brought into the market. But if there is not a ready supply of waste used goods, growth of the second-hand market can increase demand for new goods, thereby increasing material consumption. Moreover, even when second-hand sales reduce demand for new goods, it is typically not on a one-for-one basis. The extent to which the purchase of used goods replaces the purchase of new goods is shown to be an explicit function of the relative value provided by used versus new goods.  相似文献   

9.
Several new antibacterial agents are currently being developed in response to the emergence of bacterial resistance to existing drugs. The new agents include compounds that inhibit macromolecular synthesis or interfere with bacterial membrane function. Apart from the oxazolidinones and cationic peptides, the remainder of these new compounds are analogues of earlier antibiotic classes; therefore, it is probable that existing resistance mechanisms will adapt to accommodate the new derivatives. To minimise the potential for emergence of resistance to new agents, research strategies should be chosen that not only enhance the discovery of structurally novel drugs, but also direct these to new molecular targets that may themselves have decreased potential to give rise to drug-resistant variants.  相似文献   

10.
We have synthesized a new series of coumarins and furocoumarins and evaluated their vasorelaxant activity in rat aorta rings pre-contracted with noradrenaline or by depolarisation with high KCl. The new furocoumarins relax smooth vascular muscle with a profile similar to that of khellin (a furochromone that directly relaxes smooth muscle) and at a greater potency, suggesting that these compounds have a potential interest for the development of new and more efficient vasodilator drugs.  相似文献   

11.
A new species and a new variety are described: Stenandrium harlingii from prov. Morona-Santiago and S. harlingii var. angustifolia from Morona-Santiago. The new taxa are described, illustrated, and compared with their closest relatives. Four new Colombian combinations are also made: Stenandrium andrei, S. arnoldii, S. fosbergii and S. nephoica .  相似文献   

12.
The prevention and treatment of late-life dysfunction are the goals of most geriatricians and should be the primary target for discovery and development of new medicines for elderly people. However, the development of new medicines for elderly people will face a number of challenges that are not seen for other patient populations. The burdens of multiple chronic diseases, low physiological reserve and polypharmacy must result in new clinical trials in frail older people with a high expectation of safety and efficacy. The etiology of functional limitations in elderly people is complex and often ascribed to conditions that escape the traditional definition of disease. While our society urgently needs new treatments that can reduce the burden of physical decline among older persons, guidelines on how these treatments should be developed and tested are currently lacking, in part because a consensus has not yet been achieved regarding the identifiable target diseases. New potential indications included sarcopaenia, anorexia of ageing, frailty, mobility disability and reduced functional capacity secondary to hospitalization. The challenges to conducting clinical trials in the elderly should not offset the great opportunity for the development of new medicines to prevent or reverse age-associated changes in body composition and poor functional capacity in the elderly.  相似文献   

13.
The behavioural response of the brown spiny mouse, Mus platythrix Bennett to new place and new object was studied in a plus (+) maze. The new place reaction was observed by allowing the mice to access an area which had previously been not exposed to them and the new object reaction was studied by introducing a change at the feeding point. The experiment suggested new place philia and new object philia in this species.  相似文献   

14.
分子生物学与进化的新理论   总被引:6,自引:0,他引:6  
孙毅  张伟 《生物学杂志》2004,21(5):16-18
论述了由于分子生物学取得的成就,而形成的生物进化的新理论,并阐述了若干新理论指导生产实践取得的巨大应用成果。  相似文献   

15.
The roots of Brocchia cinerea afforded, in addition to known spiroketalenolether polyynes and sesquiterpene-coumarin ethers, two new isofraxidin-derived sesquiterpene ethers as well as the new 8-farnesyl-scopoletin. The structures of the new compounds were elucidated on the basis of spectroscopic evidence. The chemotaxonomic significance of sesquiterpene-coumarin ether and spiroketalenolether accumulation within the tribe Anthemideae is discussed.  相似文献   

16.
17.
The investigation of several Brickellia species and two further related species afford besides known compounds four new labdane derivatives, a new acetylenic carbinol and a new dihydrobenzofuran derivative. The structures have been elucidated by spectroscopic methods. The chemotaxonomic aspects are discussed briefly.  相似文献   

18.
The past eighteen months have provided much progress in the cyclic nucleotide phosphodiesterase (PDE) field. Six new phosphodiesterase genes have been discovered and characterized. In addition, several new highly specific PDE inhibitors have been developed and approved for clinical use. Finally, new strategies have been employed to determine PDE function in model systems including the use of antisense oligonucleotide and disruption techniques.  相似文献   

19.
The availability of bacterial genome sequence information has opened up many new strategies for antibacterial drug hunting. There are obvious benefits for the idetification and evaluation of new drug targets, but genomic-based technology is also beginning to provide new tools for the downstream, preclinical, optimisation of compounds. The greatest benefit from these new approaches lies in the ability to examine the entire genome (or several genomes) simultaneously and in total. In this way, one potential target can be evaluated against another, and either the total effects of functional impairment can be established or the effects of a compound can be compared across species.  相似文献   

20.
Molecular Biology - The emergence of new viruses and resistant strains of pathogenic microorganisms has become a powerful stimulus in the search for new drugs. Nucleosides are a promising class of...  相似文献   

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