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1.
Eighteen barley isolates of Bipolaris sorokiniana belonging to wild and clonal type of black, mixed and white subpopulations were quantitatively assayed for their melanin content and aggressiveness with respect to production of some of the extracellular enzymes such as cellulase, pectinase, amylase and protease. Cellulase and pectinase constituted major portion of the enzymes recovered from the black, mixed and white isolates. Enzyme production and aggressiveness were relatively higher in melanin devoid or low melanin isolates. The melanin deficient isolates were also differentiated from black and mixed isolates on the basis of variation in internal transcribed spacer region of the ribosomal DNA. Higher enzyme productions positively correlated with area under disease progress curve (AUDPC) and lesion development. Melanin content was negatively correlated with extracellular enzymes and aggressiveness of the isolates. Based on melanin content, lesion size, AUDPC and extracellular enzymes, the isolates were grouped in two major clusters (I and II) with further division of cluster II into two sub-clusters (II-A and II-B). The results appears to indicate a possible role of melanin in release of extracellular enzymes and hence in evolution and selection of aggressive isolates of B. sorokiniana in barley.  相似文献   
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Progeny of certain baboon sires accumulate lipoproteins in high density lipoprotein-1 (HDL1) when challenged with a high cholesterol, high saturated fat diet. These studies were conducted to determine the apoprotein composition and metabolic fate of HDL1 in the plasma. HDL1 particles containing apoA-I with and without apoE were detected. The majority of particles, however, contained apoA-I without any detectable apoE. To determine the metabolic fate of HDL1 in plasma, HDL1 labeled with iodinated apoA-I from animals with high levels of HDL1 and iodinated apoA-I-labeled autologous HDL were coinjected into both high and low HDL1 animals. The data for the decay of radioactivity in HDL1 and HDL were analyzed by multicompartment modelling. The radioactivity from HDL1 was cleared from the plasma either via direct removal (9.1 +/- 4.7% in low and 21.7 +/- 8.3% in high HDL1 animals) or via its conversion to HDL. A large proportion of radioactivity from HDL1 was rapidly transferred to HDL directly or metabolized via an intermediate compartment. Most of the radioactivity from apoE-poor HDL1, however, was transferred to HDL. Both high and low HDL1 animals catabolized HDL1 and HDL similarly. Low HDL1 animals transferred HDL1 radioactivity to HDL much faster. No detectable radioactivity from HDL was transferred to HDL1. Thus, HDL1 that accumulates in high HDL1 animals is mainly a precursor for HDL. Our hypothesis is that this accumulation of HDL1 is due to the slower cholesteryl ester transfer from HDL to lower density lipoproteins, thus affecting reverse cholesterol transport in high HDL1 baboons.  相似文献   
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Multiple shoots were produced from nodal explants of cassava (Manihot esculenta Crantz) by a two-step procedure: a 6- to 8-day exposure to 0.11–0.22 µM thidiazuron (TDZ) in liquid Murashige and Skoog (MS) medium followed by culture on agar-solidified MS medium supplemented with 2.2 µM 6-benzyladenine (BA) and 1.6 M gibberellic acid (GA3). TDZ caused the nodal explants to expand and this expansion (growth) continued during culture with BA and GA3. From this expanded explant, clusters of buds and fasciated stems developed continuously and these gave rise to shoots. The shoot proliferation process was open-ended, yielding an average of 31.5 shoots per nodal explant after 10 weeks of culture with genotype CG 1–56. A positive response was also obtained from seven other genotypes evaluated with this protocol.Abbreviations BA 6-benzyladenine - BM basal medium - DPU 1,3-diphenylurea - GA3 gibberellie acid - 2iP isopentenyladenine - MSM multiple shoot medium - NAA 1-naphthaleneacetic acid - PGR plant growth regulator - TDZ thidiazuron - Z zeatin  相似文献   
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Gagui  S.  Meradji  H.  Ghemid  S.  Naeem  S.  Haq  Bakhtiar Ul  Ahmed  R.  Kushwaha  A. K. 《Journal of molecular modeling》2023,29(1):1-13
Journal of Molecular Modeling - The recent advances in the application of machine learning to drug discovery have made it a ‘hot topic’ for research, with hundreds of academic groups...  相似文献   
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Direct comparison of purple membrane preparations from Halobacterium cutirubrum and Halobacterium halobium was carried out. Both preparations were found to be essentially identical with respect to their molecular weight, retinal content, lipid composition, fingerprinting of peptides from peptide digestion, electron micrographs and X-ray diffraction patterns, and behaviour as a light-activated proton pump. Thus, there would appear to be no species differences in the purple membranes from these two bacteria.  相似文献   
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The polar acetone-soluble lipids of Halobacterium cutirubrum were found to contain (in addition to the previously reported vitamin MK-8 and retinal) neo-bacterioruberin U, bacterioruberin, monoanhydrobacterioruberin, bis-anhydrobacterioruberin, an isomer of geranylgeraniol (with one internal cis-isoprene residue), 2,3,-di-O-phytanyl-sn-glycerol and two unidentified polar isoprenoids. All compounds were isolated in pure form by column and thin-layer chromatography, quantitated and characterized by their visible, ultraviolet, infrared, proton magnetic resonance and mass spectra and the spectra of their acetyl or silyl derivatives and/or dehydrated products.  相似文献   
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Biological Trace Element Research - This study was conducted to investigate the effect of vanadium (V) supplementation on growth, metabolism, antioxidant, and immunological and endocrine variables...  相似文献   
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