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171.
ISSR标记在黑木耳单核体遗传分析中的应用 总被引:1,自引:0,他引:1
采用原生质体单核化和单孢分离法分别获得黑木耳Auricularia auricula栽培菌株新科5号两个亲本单核体(T1、T2)和33个F1代孢子单核体。从73条ISSR引物中筛选出13条可区分两个亲本单核体(T1、T2)的引物,对新科5号及F1代孢子单核体进行扩增,共扩增出70条带,其中63条在供试菌株间表现出多态性,多态位点百分率为90.0%。根据扩增结果采用软件NTsys2.10e计算菌株间的遗传相似系数并进行聚类分析,36个菌株间的遗传相似系数(GS值)的变化范围为0.2500~0.8382,其中T1和T2之间的GS值最小,遗传相似程度最低;F1代33个孢子单核体中24个与T1聚为一类,其余9个与T2聚为另一类,但并非严格按照交配型进行归类。试验表明黑木耳子实体上各个担子在减数分裂中染色体交换极具多样性,F1代孢子单核体表现出偏向其中一个亲本的现象,ISSR标记在黑木耳杂交育种中具有潜在的应用价值。 相似文献
172.
Pyruvate dehydrogenase complex (PDC) deficiency is an inborn metabolic disorder that causes neurological abnormalities. In
this report, a murine model of PDC deficiency was analyzed using histology, magnetic resonance (MR) imaging and MR spectroscopy
(MRS) and the results compared to PDC-deficient female patients. Histological analysis of brains from PDC-deficient mice revealed
defects in neuronal cytoarchitecture in grey matter and reduced size of white matter structures. MR results were comparable
to previously published clinical MR findings obtained from PDC-deficient female patients. Specifically, a 15.4% increase in
relative lactate concentration, 64.4% loss of N-acetylaspartate concentration and a near complete loss of discernable glutamine plus glutamate concentration were observed
in a PDC deficient mouse compared to wild-type control. Lower apparent diffusion coefficients (ADCs) were observed within
the brain consistent with atrophy. These results demonstrate the usefulness of this murine model to systematically evaluate
the beneficial effects of dietary and pharmacological interventions.
Special issue dedicated to John P. Blass.
Lioudmila Pliss and Richard Mazurchuk are two investigators who contributed equally. 相似文献
173.
Tomato (Solanum lycopersicum L.) is called ‘the poor man’s orange’ due to its low price and improved nutritional values. An experiment was conducted to study the breeding potential of some exotic tomato lines by assessing various qualitative and quantitative traits conferring yield and quality attributes. Among the qualitative traits, greater variability was observed for growth type, stem hairiness, and fruit shape and size. A determinate growth habit was observed in the genotype AVTO9802 while the genotype AVTO0102 produced yellow color fruits. A significant (p ≤ 0.01) variation was also observed for the studied quantitative traits. Based on yield and traits attributed to yield, the genotypes AVTO0314, GPB0107, GPB0120 and AVTO9802 were selected as promising genotypes. The differences between the genotypic and phenotypic coefficients of variation (GCV and PCV) of the studied quantitative traits were very low. This suggests that the apparent variation was mainly due to the genotypes. The higher GCV and PCV values were observed for the number of primary branches plant−1 (NPB), number of fruits cluster−1 (NFC), individual fruit weight (IFW) and total soluble solids (TSS). High heritability was recorded for all quantitative traits in a broad sense. However, the individual fruit diameter showed the highest heritability (99.56). The highest (102.75) genetic advance (GA) was observed for the number of fruits plant−1 (NFP). High heritability coupled with high GA as percentage of mean were recorded for the traits NFP, NFC, fruit yield plant−1 (FYP) and IFW. FYP showed a significant positive correlation with NFC (0.714***) and a negative correlation with days to the first harvest (−0.539***) and plant height (−0.492**). Principal component analysis revealed that the first four components explained 78.5% of the total variation among the genotypes. Thus, the promising genotypes (AVTO0314, GPB0107, GPB0120, AVTO9802 and AVTO0102) isolated from this study can be used for developing high-yielding and high-quality tomato varieties. 相似文献
174.
Mohammed I. Al-Daej Mohamed M. El-Malky Muhammad N. Sattar Adel A. Rezk Muhammad N. Naqqash Jameel M. Al-Khayri 《Phyton》2022,91(9):1905-1922
Rice stem borer (Chilo agamemnon Bles.) is a primary insect pest of rice and is a major limiting factor to rice
production. Breeding for insect-resistant crop varieties has been an economic way of integrated pest management
(IPM) as it offers a viable and ecologically acceptable approach. This study was aimed to evaluate rice genotypes
for their resistance against rice stem borer. Seven parental genotypes with twenty one F1 crosses were evaluated
for genotypic variation in field experiments. Analysis of variance revealed significant differences for the studied
traits in almost all crosses and parents. In addition, the mean squares of parents versus their crosses were signifi-
cant for stem borer resistance and other associated traits. Moreover, both general combining ability (GCA) and
specific combining ability (SCA) variances were highly significant for all characters studied in the F1 generation.
Based on GCA, 4 genotypes (Sakha101, Gz6903-3-4-2-1, Gz9577-4-1-1 and Hassawi) exhibited highly significant
negative values for stem borer resistance (–0.53, –1.06, –0.18 and –0.49, respectively) indicating they are the best
combiners for stem borer resistance. Based on SCA analysis, nine cross combinations showed highly significant
negative effects for stem borer resistance. Similarly, the cross Giza178 Hassawi was the best combination with
significantly highest value for early maturity. In addition, seven crosses showed highly significant negative
SCA for plant height trait. On the other hand, for panicle length, number of primary branches/panicle, panicle
weight and 1000-grain weight, seven, four, eight and six crosses showed highly significant positive SCA, respectively. The result further revealed that the non-additive dominance genetic variance was higher than the additive
variance for all evaluated traits indicating that non-additive genetic variances have a role in their inheritance. The
broad-sense heritability estimates were high for all the studied traits. The stem borer resistance was significantly
correlated with panicle weight and 1000-grain weight, which also showed a highly significant correlation with
grain yield/plant. Thus these traits can be effectively employed in a breeding program to confer resistance against
stem borer infestation in rice. It was further supported by biplot analysis, which clustered these potentially important traits into two quadrants showing their importance in any future breeding program to control stem borer
infestation. This study has contributed valuable information for evaluation of genetic diversity in the local rice
germplasm and its utilization in futuristic rice genetic improvement programs. 相似文献
175.
为评价热消散法在竹子蒸腾耗水测定中的适用性,利用室内离体竹段注水变压法结合野外整株容器称重法对Granier 公式进行了验证和系数校正,同时观察了5 种竹子(毛竹Phyllostachys edulis、粉单竹Bambusa chungii、青皮竹B. textilis、茶秆竹Arundinaria amabilis、龙头竹B. vulgaris)的茎秆维管束结构。结果表明,茎秆维管束分布不均,维管束发育程度从竹壁外向内逐渐成熟,输水能力也逐渐增强。液流密度(Fd)和液流指数(K)呈幂函数关系,相关系数R2>0.83,说明热消散探针方法能较好地估算竹类的液流密度。用整株容器称重法对推导出的液流密度公式进行校正,校正后的液流密度公式与原始Granier 公式中各系数均不同,尤其是α 值。分别采用校正前后公式计算的竹子日蒸腾量差异显著,尤其是一天中液流高峰时段(午间)的差异最大。因此,只要对热消散探针方法准确验证、校正Granier 原始公式系数,TDP 技术是估计竹类植物水分利用的一种适宜方法。 相似文献
176.
Dionne C.G. Klein Astrid Skjesol Esther D. Kers‐Rebel Tatyana Sherstova Bjrnar Sporsheim Kjartan W. Egeberg Bjrn T. Stokke Terje Espevik Harald Husebye 《Traffic (Copenhagen, Denmark)》2015,16(7):677-690
Toll‐like receptor 4 (TLR4) is responsible for the immediate response to Gram‐negative bacteria and signals via two main pathways by recruitment of distinct pairs of adaptor proteins. Mal‐MyD88 [Mal (MyD88‐adaptor‐like) ‐ MYD88 (Myeloid differentiation primary response gene (88))] is recruited to the plasma membrane to initiate the signaling cascade leading to production of pro‐inflammatory cytokines while TRAM‐TRIF [TRAM (TRIF‐related adaptor molecule)‐TRIF (TIR‐domain‐containing adapter‐inducing interferon‐β)] is recruited to early endosomes to initiate the subsequent production of type I interferons. We have investigated the dynamics of TLR4 and TRAM during lipopolysaccharide (LPS) stimulation. We found that LPS induced a CD14‐dependent immobile fraction of TLR4 in the plasma membrane. Total internal reflection fluorescence microscopy (TIRF) revealed that LPS stimulation induced clustering of TLR4 into small punctate structures in the plasma membrane containing CD14/LPS and clathrin, both in HEK293 cells and the macrophage model cell line U373‐CD14. These results suggest that laterally immobilized TLR4 receptor complexes are being formed and prepared for endocytosis. RAB11A was found to be involved in localizing TRAM to the endocytic recycling compartment (ERC) and to early sorting endosomes. Moreover, CD14/LPS but not TRAM was immobilized on RAB11A‐positive endosomes, which indicates that TRAM and CD14/LPS can independently be recruited to endosomes. 相似文献
177.
A laboratory-scale anaerobic-anoxic-oxic (AAO) system was established to investigate the fate of DnBP. A removal kinetic model including sorption and biodegradation was formulated, and kinetic parameters were evaluated with batch experiments under anaerobic, anoxic, oxic conditions. However, it is highly complex and is difficult to confirm the kinetic parameters using conventional mathematical modeling. To correlate the experimental data with available models or some modified empirical equations, an artificial neural network model based on multilayered partial recurrent back propagation (BP) algorithm was applied for the biodegradation of DnBP from the water quality characteristic parameters. Compared to the kinetic model, the performance of the network for modeling DnBP is found to be more impressive. The results showed that the biggest relative error of BP network prediction model was 9.95%, while the kinetic model was 14.52%, which illustrates BP model predicting effluent DnBP more accurately than kinetic model forecasting. 相似文献
178.
Miyamoto Y Banno Y Yamashita T Fujimoto T Oi S Moritoh Y Asakawa T Kataoka O Takeuchi K Suzuki N Ikedo K Kosaka T Tsubotani S Tani A Funami M Amano M Yamamoto Y Aertgeerts K Yano J Maezaki H 《Bioorganic & medicinal chemistry》2011,19(1):172-185
We have previously discovered nicotinic acid derivative 1 as a structurally novel dipeptidyl peptidase IV (DPP-4) inhibitor. In this study, we obtained the X-ray co-crystal structure between nicotinic acid derivative 1 and DPP-4. From these X-ray co-crystallography results, to achieve more potent inhibitory activity, we targeted Arg125 as a potential amino acid residue because it was located near the pyridine core, and some known DPP-4 inhibitors were reported to interact with this residue. We hypothesized that the guanidino group of Arg125 could interact with two hydrogen-bond acceptors in a bidentate manner. Therefore, we designed a series of 3-pyridylacetamide derivatives possessing an additional hydrogen-bond acceptor that could have the desired bidentate interaction with Arg125. We discovered the dihydrochloride of 1-{[5-(aminomethyl)-2-methyl-4-(4-methylphenyl)-6-(2-methylpropyl)pyridin-3-yl]acetyl}-l-prolinamide (13j) to be a potent and selective DPP-4 inhibitor that could interact with the guanidino group of Arg125 in a unique bidentate manner. 相似文献
179.
利用太子河流域6个主要支流(海城河、南沙河、北沙河、兰河、细河、太子河南支)1967—2006年日均降水和径流资料,分析了各支流径流系数的变化趋势及其与降水的关系.结果表明:1967—2006年,位于高山丘陵区的太子河南支的年均径流系数较大,而人类活动影响较多的海城河流域的年均径流系数较小;除南沙河的年径流系数总体呈上升趋势外,其余各条支流的年径流系数均呈下降趋势,以南支和兰河的下降趋势尤为明显;除细河流域的年径流系数没有发生突变外,其余各条支流的年径流系数都发生了突变,且突变出现的年份各不相同;年降水量对年径流系数的影响极显著. 相似文献
180.
种植条件下海滨盐土理化性状与生物学特征 总被引:1,自引:0,他引:1
以苏北海滨盐土种植实验区7个不同特征的地块为对象,研究了海滨盐土基本理化性状及其生物学特征的季节变化,以及其与植物种植和植被条件的关系.结果表明:海滨盐土的土壤性状随种莓年限和植被状况的不同有较大的变异性,种植耐盐植物地块平均土壤电导率(0.95 dS·m-1)低于自然植被地块(2.77 dS·m-1),但部分地块电导率水平较种植前有所升高;土壤肥力普遍较低,水解性氮含量平均低于50 mg·kg-1,有效磷含量(除施肥地块)平均低于3 mg·kg-1,有机质含量低于1%,种植耐盐植物地块因施肥而有所改善.土壤电导率和养分水平是影响盐土植被生长与分布的主要因素,前者尤为关键;土壤氮磷含量与微生物数量密切相关.不同植被和干扰状况下土壤性状的季节变化差异明显,植被盖度高、人为干扰少的土壤环境相对稳定,反之则波动剧烈. 相似文献