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1.
挖掘与稻米蒸煮品质相关的数量性状基因座(quantitative trait locus, QTL),分析候选基因,并通过遗传育种手段改良稻米蒸煮品质相关性状,可有效提升稻米的口感。以籼稻华占(Huazhan, HZ)、粳稻热研2号(Nekken2)及由其构建的120个重组自交系(recombinant inbred lines, RILs)群体为实验材料,测定成熟期稻米的糊化温度(gelatinization temperature, GT)、胶稠度(gel consistency, GC)和直链淀粉含量(amylose content, AC)。结合高密度分子遗传图谱进行QTL定位,共检测到26个与稻米蒸煮品质相关的QTLs (糊化温度相关位点1个、胶稠度相关位点13个、直链淀粉含量相关位点12个),其中最高奇数的可能性(likelihood of odd, LOD)值达30.24。通过实时荧光定量PCR (quantitative real-time polymerase chain reaction, qRT-PCR)分析定位区间内候选基因的表达量,发现6个基因在双亲间的表达量差异显著,推测LOC_Os04g20270LOC_Os11g40100的高表达可能会极大地提高稻米的胶稠度,而LOC_Os01g04920LOC_Os02g17500的高表达以及LOC_Os03g02650LOC_Os05g25840的低表达有助于降低直链淀粉含量。这些结果为培育优质水稻新品种奠定了分子基础,并为揭示稻米蒸煮品质的分子调控机制提供了重要的遗传资源。  相似文献   

2.
Infestation of banana and plantain suckers by nematodes (Pratylenchus good-eyi, Radopholus similis and Helicotylenchus multicinctus) and weevils (Cosmopolites sordidus) increased with time from establishment in a field of eight different cultivars. There was a strong association between nematode and weevil infestation; suckers infested with nematodes were more than four times more likely to be infected by weevil than suckers without nematodes. Weevil damage, measured by percentage coefficient of infestation (PCI) at harvest of the bunch, was higher on a plantain (cv. Gonja) and on an east African highland cooking banana (cv. Lusumba) than on the sweet and multi-purpose cultivars. There was a correlation between numbers of male weevils caught in a plot and the mean PCI measured in the plot, but no correlation with female numbers.  相似文献   

3.
原位双膜法是一种基于免疫原理的快速筛选高表达甲醇酵母转化子的方法,即首先将固体培养基上的菌落转印至醋酸纤维素薄膜上,再利用硝酸纤维素薄膜原位捕获穿过醋酸纤维素薄膜的菌落外泌蛋白,然后用免疫方法检测与硝酸纤维素薄膜结合的蛋白.利用此法筛选到人Flt3配体(hFL)的甲醇酵母高表达转化子,液体诱导表达量约20 mg/L.ELISA结果证明,原位双膜法所得的菌落染色强度与该菌落液体诱导表达水平正相关.蛋白质印迹结果显示,培养上清在25 ku处有明显杂交条带,而对照组杂交呈阴性,且表达量随诱导天数增加.原位双膜法是一种良好的筛选方法,可以快捷、准确地筛选高表达酵母转化子.  相似文献   

4.
5.
The statins (3‐hydroxy‐3‐methylglutaryl coenzyme A reductase inhibitors) were proven to be effective antilipid agents against cardiovascular disease. Recent reports demonstrate an anticancer effect induced by the statins through inhibition of cell proliferation, induction of apoptosis, or inhibition of angiogenesis. These effects are due to suppression of the mevalonate pathway leading to depletion of various downstream products that play an essential role in cell cycle progression, cell signaling, and membrane integrity. Recent evidence suggests a shared genomic fingerprint between embryonic stem cells, cancer cells, and cancer stem cells. Activation targets of NANOG, OCT4, SOX2, and c‐MYC are more frequently overexpressed in certain tumors. In the absence of bona fide cancer stem cell lines, human embryonic stem cells, which have similar properties to cancer and cancer stem cells, have been an excellent model throwing light on the anticancer affects of various putative anticancer agents. It was shown that key cellular functions in karyotypically abnormal colorectal and ovarian cancer cells and human embryonic stem cells are inhibited by the statins and this is mediated via a suppression of this stemness pathway. The strategy for treatment of cancers may thus be the targeting of a putative cancer stem cell within the tumor with specific agents such as the statins with or without chemotherapy. The statins may thus play a dual prophylactic role as a lipid‐lowering drug for the prevention of heart disease and as an anticancer agent to prevent certain cancers. This review examines the relationship between the statins, stem cells, and certain cancers. J. Cell. Biochem. 106: 975–983, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   

6.
In an olfactometer study on the response of the anthropophilic malaria mosquito Anopheles gambiae s.s. (Diptera, Culicidae) to human sweat it was found that freshly collected sweat, mostly of eccrine origin, was attractive, but that incubated sweat was significantly more attractive than fresh sweat. The behavioural response to l ‐lactic acid and ammonia, the main constituents of sweat, was investigated. l ‐lactic acid was attractive at one concentration only (11.11 mm ) and removal of the l ‐lactic acid from the sweat by enzymatic decomposition did not affect the attractiveness of sweat. Ammonia caused attraction over a range of 0.1–13.4 m on glass slides and at 0.84–8.40 μmol/min in an air stream. It is concluded that: human sweat contains kairomones for host‐seeking An. gambiae; ammonia is an important kairomone for this mosquito; and that l ‐lactic acid is not a prerequisite in the attraction of An. gambiae to sweat.  相似文献   

7.
The cooking and eating quality of rice has attracted more attention recently. In a comprehensive effort to unravel its genetic basis, we conducted a genome-wide analysis of six traits representing the cooking and eating quality of rice grain, namely, amylose content (AC), gel consistency (GC), gelatinization temperature (GT), water absorption (WA), cooked rice elongation (CRE) and volume expansion (VE) using a DH population derived from the anther culture of an F1 hybrid between WYJ 2 (japonica) and Zhenshan 97B (indica). For each trait, one to three quantitative trait loci (QTL) were found, which were located on chromosomes 1, 2, 3, 6, 11. QTL analysis revealed a major QTL specifying GT, located at the interval RM276-RM121, which should be the same locus as the alkali degeneration gene (alk), while for each of the remaining five traits the QTL explaining the largest proportion of variance was located on the short arm of chromosome 6, centered at RM190 (found in the waxy gene). Our results, in combination with previous reports, further confirmed that either the waxy gene itself or a genomic region tightly linked to it plays a major role in determining the cooking and eating quality of rice.  相似文献   

8.
The speed of protein digestion impacts on postprandial protein anabolism. After exercise or in the elderly, fast proteins stimulate protein synthesis more efficiently than slow proteins. It has been shown that meat might be a source of fast proteins. However, cooking temperature, acting on the macrostructure and microstructure of the meat could affect both the speed, and efficiency, of protein digestion. This study aims to evaluate, in vivo, the effect of meat cooking on digestion parameters, in the context of a complete meal. Six minipigs fitted with an ileal cannula and an arterial catheter were used. In order to measure the true ileal digestibility, tested meat was obtained from a calf, the muscle proteins of which were intrinsically labelled with 15N-amino acids. Three cooking temperatures (60, 75 and 95°C; core temperature for 30 min), and three levels of intake (1, 1.45, and 1.90 g protein/kg body weight) were tested. Following meat ingestion, ileal digesta and arterial blood were collected over a 9-h period. The speed of digestion, evaluated from the kinetics of amino acid appearance in blood within the first 3 h, was greater for the cooking temperature of 75°C, than for 60 or 95°C. The true ileal digestibility, which averaged 95%, was not affected by cooking temperature or by the level of meat intake. The amino acid composition of the digesta flowing at the ileum was not affected by cooking temperature. These results show that cooking temperature can modulate the speed of meat protein digestion, without affecting the efficiency of the small intestinal digestion, and consequently the entry of meat protein residues into the colon.  相似文献   

9.
Summary Three different mulching materials — hay, black polyethylene film, and translucent polyethylene film — produced different soil temperatures and thus influenced the microflora of the soil differently.Rhizoctonia solani Kuehn increased in cool or moderate temperatures under hay or black film but not in warmer soil beneath translucent film. Populations of a meadow nematode,Pratylenchus penetrans Cobb were reduced approximately two-thirds under the black film. Under this film conditions apparently favor biological control ofP. penetrans. Over several months this control was destroyed if a fungicide, pentachloronitrobenzene, and a nematocide, dibromochloropropane, were added. Evidently, the fungicide inhibited organisms predaceous onP. penetrans at the same time it inhibitedR. solani.  相似文献   

10.
Summary Wastewater from fiber board manufacture consisting in a mixture of Pinus radiata, Eucaliptus globulus and Laureliopsis phillipiana (tepa) (3:1:1) has been studied in laboratory scale activated sludge reactors with organic load rate range of 50–1700 gCOD/m3.d. A stable operation at high organic load rate with hydraulic retention time of one day was achieved. Purification efficiencies up to 90 % of COD removal could be achieved in an activated sludge treatment of fiber board wastewater working with 1 day HRT for wood log cooking wastewater and with 4 days HRT when glueing wastewater is added to the cooking wastewater treatment. Suspended solids, color and phenol concentration were negligible in the efluent of the activated sludge system.  相似文献   

11.

“Women's film” in Hollywood is associated both with the genre of melodrama, the “weepie”, and with female spectatorship. In the Indian context of popular Hindi cinema, first, genre analysis itself is a questionable line of inquiry since several genres, the melodrama, musical, gangster, or mystery, combine in a single film, known locally as the masala (spicy) film; and second, films are scarcely divided by a gendered viewership. Yet I identify “women's films” as a distinct category in Hindi cinema, emerging around the ‘70s. These women's films typically center on female protagonists, dramatize their victimization and vindication; by the ‘80s under a range of influences these films mutated into rape‐revenge narratives.

However, another strain emerged within the ‘70s’ “women's film,” which drew on cinema's rich visual iconographic tradition of the sight gag, promulgating the comedic/tomboy heroine figure. It favored laughing and mocking patriarchal structures rather than surrendering to them in tears. Focusing on Ramesh Sippy's Sita aur Gita [1972] emblematic of this trend I explore theoretical concerns about associating genres with gender. In keeping with recent poststructuralist theories about gender and media ‘consumption I show how the film destabilized clear‐cut gender identification and stood for a promising trend that was sadly undercut. Thus, while genre might still be a useful analytical tool for Hindi cinema, defining women's film as female‐centered narratives is a viable category as long as we appreciate the instability in gendered viewer identification.  相似文献   

12.
In addition to its role as an energy source for plants, animals and humans, starch is also an environmentally friendly alternative to fossil fuels. In rice, the eating and cooking quality of the grain is determined by its starch properties. The floury endosperm of rice has been explored as an agronomical trait in breeding and genetics studies. In the present study, we characterized a floury endosperm mutant, flo(a), derived from treatment of Oryza sativa ssp. japonica cultivar Hwacheong with MNU. The innermost endosperm of the flo(a) mutant exhibited floury characteristics while the outer layer of the endosperm appeared normal. Starch granules in the flo(a) mutant formed a loosely-packed crystalline structure and X-ray diffraction revealed that the overall crystallinity of the starch was decreased compared to wild-type. The FLO(a) gene was isolated via a map-based cloning approach and predicted to encode the tetratricopeptide repeat domaincontaining protein, OsTPR. Three mutant alleles contain a nucleotide substitution that generated one stop codon or one splice site, respectively, which presumably disrupts the interaction of the functionally conserved TPR motifs. Taken together, our map-based cloning approach pinpointed an OsTPR as a strong candidate of FLO(a), and the proteins that contain TPR motifs might play a significant role in rice starch biosynthetic pathways.  相似文献   

13.
The cooking and eating quality of the rice grain is one of the most serious problems in many rice-producing areas of the world. In this study, we conducted a molecular marker-based genetic analysis of three traits, amylose content (AC), gel consistency (GC) and gelatinization temperature (GT), that are the most important constituents of the cooking and eating quality of rice grains. The materials used in the analysis included F2 seeds, an F2:3 population, and an F9 recombinant inbred-line population from a cross between the parents of ’Shanyou 63’, the most widely grown hybrid in rice production in China. Segregation analyses of these three generations showed that each of the three traits was controlled by a single Mendelian locus. Molecular marker-based QTL (quantitative trait locus) analyses, both by one-way analysis of variance using single marker genotypes and by whole-genome scanning with MAPMAKER/QTL, revealed a single locus that controls the expression of all three traits. This locus coincided with the Wx region on the short arm of chromosome 6, indicating that all three traits were either controlled by the Wx locus or by a genomic region tightly linked to this locus. This finding has provided clues to resolving the molecular bases of GC and GT in future studies. The results also have direct implications for the quality improvement of rice varieties. Received: 5 January 1999 / Accepted 30 January 1999  相似文献   

14.
This paper presents a simple method to extract information about thin organic films from surface plasmon resonance (SPR) spectra. From numerical simulations it was found that a shift (Δθ SPR) of an absorption peak in the SPR spectrum was directly proportional to the product of the thin organic film thickness and the refractive index difference between the thin organic film and a buffer soaking the sample. It was also found that Δθ SPR was not sensitive to the thin organic film support of a gold film and a glass cover slip. Relationships between Δθ SPR and distributions of macromolecule structures, in the thin organic films were theoretically established. Formulae were derived for a homemade SPR system to calculate length, transverse area, density and surface concentration of macromolecules in the thin organic film. The validity of these treatments was checked by precisely measuring the size of a single distearoylphosphatidylcholine molecule on a gold-supported phospholipid film; by quantitatively monitoring hybridization of synthesized oligonucleotides strands based on a biotin/avidin system; and by quantitatively detecting the steric hindrance of rabbit C-reactive protein specifically bound to phospholipid monolayers composed of synthesized lipids. Received: 4 May 1998 / Revised version: 27 July 1998 / Accepted: 27 August 1998  相似文献   

15.
Unicapsula seriolae n. sp. forms long plasmodia within the striated muscle fibers of Seriola lalandi off eastern Australia. Its spores are composed of three valves, only one of which contains a developed polar capsule. Within the capsule, the filament makes 2 1/2–3 turns, and this criterion can be used to separate U. seriolae from the two other members of the genus. The flesh of infected fish disintegrates during slow cooking.  相似文献   

16.
Summary 1. On the coral reefs of the Tuléar region (S. W. Madagascar), the feeding behaviour of sea stars, in particular the speciesCulcita schmideliana has been studied. It feeds in its usual biotope, the sea-grass beds of the inner reef flats, on the epibenthic film of the substrates, of the leaves, but also commonly on sponges, mainly the symbioticGellius cymiformis (associated withCeratodictyon spongiosum);2. In the moat (residual pools, coral-built formations) of the inner reef flat where the population was poor in 1965 but equal to that of the sea-grass bed in 1972, the cushion sea star feeds on the epibenthic felt, but also on the living corals (Galaxea, Goniopora) and on soft corals(Xenia). This latter diet is very close to that of the Pacific cogeneric species,Culcita novaeguinae.3.Acanthaster planci populations are normal on the reef flats of the region (but a little more dense on the fringing reef under silty deposits). Only a beginning of an infestation was observed in May 1972, but it disappeared later (condition 6 of Chesher's classification).4. Others Oreasterids feed mainly on epibenthic film, extruding their stomachs on the substrates.Protoreaster nodosus has a larger distribution thanP. lincki, Pentaceraster mammillatus andChoriaster granulosus.5. Among others sea stars,Asterina burtoni seems to be a large predator of species living under dead coral blocks (sponges, ascidiacea) of the boulder tracts and of the rubbly flats.
Ethologie alimentaire des Stéllérides mangeuses de film épibenthique, d'éponges et de madréporaires, principalement deCulcita schmideliana
Resume Sur les récifs coralliens de la région de Tuléar (Madagascar), les éthologies alimentaires des Stéllérides de l'épifaune ont été étudiées, particulièrement celle deC. schmideliana. Cette espèce colonise habituellement les herbiers de Phanérogames des platiers récifaux internes; dans ce biotope, elle se nourrit toujours en extroversant son estomac, soit sur le film épipsammique ou épiphytique (riche en algues microscopiques, diatomées, bactéries, foraminifères et méiofaune), soit sur les colonies deGellius cymiformis, éponge associée à une algue filamenteuse et qui vit à la surface du sédiment. Récemment (en 1971–72) des populations deC. schmideliana se sont développées dans les formations coralliennes du platier récifal interne (platier compact, platier à éléments dispersés, platier à alignements coralliens et couloirs sableux); dans ces biotopes particuliers, cette étoile de mer se nourrit du film épibenthique croissant à la surface des colonies mortes (algues et faunule associée), ou bien de madréporaires vivants(Galaxea, Goniopora), d'éponges ou d'alcyonnaires(Xenia). Ce comportement nutritionel particulier et non dévut est analysé; des hypothèses sur les causes de cette migration sont avancées. Par ailleurs, la distribution et les éthologies alimentaires d'autres Stéllérides épibenthiques habitant les récifs coralliens, telles que:Acanthaster planci, Linckia laevigata etL. multifora, Nardoa variolata, Echinaster purpureus, Monachaster sanderi, Asterina burtoni, Choriaster granulosus, Protoreaster nodosus etP. lincki, Pentaceraster mammillatus, sont décrites et discutées.
  相似文献   

17.
【目的】分离并鉴定具有聚乙烯材料降解能力的微生物菌株,探究其降解农用地膜的效能,为地膜的微生物降解途径提供支撑。【方法】以线性低密度聚乙烯粉末为唯一碳源的培养物中分离出1株具有降解聚乙烯材料能力的真菌,利用分子生物学方法结合菌株的培养性状对该菌株进行鉴定,通过观察聚乙烯粉末降解情况和测定地膜失重率,结合红外扫描、高分辨场发射扫描电子显微镜分析该菌株对农用地膜的降解效果。【结果】筛选获得1株具有农用地膜降解效果的真菌菌株PT1,经鉴定为桔青霉(Penicillium citrinum),桔青霉PT1菌株能以重均分子量(Mw)2000和400000的聚乙烯粉末作为唯一碳源生长,经红外扫描、电镜观察发现桔青霉PT1可侵蚀传统聚乙烯地膜。桔青霉PT1能快速利用聚酯类生物降解地膜生长,35 d地膜失重率达50%左右。【结论】本文筛选到具有地膜降解特性的桔青霉PT1真菌,丰富了降解聚乙烯材料的微生物类群,同时也为废弃农用地膜的处理提供了环保的处理途径。  相似文献   

18.
Cd‐free Cu(In,Ga)(S,Se)2 (CIGSSe) solar cells are fabricated by an all‐dry process (a Cd‐free and all‐dry process CIGSSe solar cell) with aged CIGSSe thin film absorbers. The aged CIGSSe thin films are kept in a desiccator cabinet under partial pressure of oxygen of ≈200 Pa for aging time up to 10 months. It is reported for the first time that aged CIGSSe thin film with increased aging time results in significant enhancement of photovoltaic performance of Cd‐free and all‐dry process CIGSSe solar cells, regardless of the alkali treatment. Based on carrier recombination analysis, carrier recombination rates at the interface and in the depletion region of the Cd‐free and all‐dry process CIGSSe solar cells are reduced owing to avoidance of sputtering damage on CIGSSe absorber surface, which is consistent with the strong electron beam‐induced current signal near CIGSSe surface after the increased aging time. It is implied that the interface and near‐surface qualities are clearly improved through the increased aging time, which is attributable to the self‐forming of Inx(O,S)y near CIGSSe surface, which acts as a buffer layer. Ultimately, the 22.0%‐efficient Cd‐free CIGSSe solar cell fabricated by all‐dry process is achieved with the aged Cs‐treated CIGSSe absorber with the aging time of 10 months.  相似文献   

19.
Assessments of temporal bone morphology have played an important role in taxonomic and phylogenetic evaluations of fossil taxa, and recent three‐dimensional analyses of this region have supported the utility of the temporal bone for testing taxonomic and phylogenetic hypotheses. But while clinical analyses have examined aspects of temporal bone ontogeny in humans, the ontogeny of the temporal bone in non‐human taxa is less well documented. This study examines ontogenetic allometry of the temporal bone in order to address several research questions related to the pattern and trajectory of temporal bone shape change during ontogeny in the African apes and humans. We further apply these data to a preliminary analysis of temporal bone ontogeny in Australopithecus afarensis. Three‐dimensional landmarks were digitized on an ontogenetic series of specimens of Homo sapiens, Pan troglodytes, Pan paniscus, and Gorilla gorilla. Data were analyzed using geometric morphometric methods, and shape changes throughout ontogeny in relation to size were compared. Results of these analyses indicate that, despite broadly similar patterns, African apes and humans show marked differences in development of the mandibular fossa and tympanic portions of the temporal bone. These findings indicate divergent, rather than parallel, postnatal ontogenetic allometric trajectories for temporal bone shape in these taxa. The pattern of temporal bone shape change with size exhibited by A. afarensis showed some affinities to that of humans, but was most similar to extant African apes, particularly Gorilla. Am J Phys Anthropol 151:630–642, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   

20.
The percentage of amylose in the endosperm of rice (Oryza sativa) largely determines grain cooking and eating qualities. Granule‐bound starch synthase I (GBSSI) and GBSSII are responsible for amylose biosynthesis in the endosperm and leaf, respectively. Here, we identified OsGBP, a rice GBSS‐binding protein that interacted with GBSSI and GBSSII in vitro and in vivo. The total starch and amylose contents in osgbp mutants were significantly lower than those of wild type in leaves and grains, resulting in reduced grain weight and quality. The carbohydrate‐binding module 48 (CBM48) domain present in the C‐terminus of OsGBP is crucial for OsGBP binding to starch. In the osgbp mutant, the extent of GBSSI and GBSSII binding to starch in the leaf and endosperm was significantly lower than wild type. Our data suggest that OsGBP plays an important role in leaf and endosperm starch biosynthesis by mediating the binding of GBSS proteins to developing starch granules. This elucidation of the function of OsGBP enhances our understanding of the molecular basis of starch biosynthesis in rice and contributes information that can be potentially used for the genetic improvement of yield and grain quality.  相似文献   

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