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131.
拟南芥氨基酸透性酶1(AAP1,也叫NAT1)是植物中第一个被分离的氨基酸转运蛋白,在拟南芥主根、侧根、根毛及根表皮细胞中均有增加氨基酸含量的作用。本研究利用RT-PCR的方法,从拟南芥中克隆了该基因,测序结果与GenBank(NM-104616.4)中已发表的拟南芥AAP1(AtAAP1)基因的同源性高达99.93%;并将AtAAP1基因与pCAMBIA3300构建p3300-AAP1植物表达载体,为过表达AtAAP1基因,提高作物氨基酸含量,从而改善作物氮素利用效率提供参考。  相似文献   
132.
Refined cobia liver oil is a nutritional supplement (CBLO) that is rich in polyunsaturated fatty acids (PUFAs), such as DHA and EPA; however, PUFAs are prone to oxidation. In this study, the fabrication of chitosan-TPP-encapsulated CBLO nanoparticles (CS@CBLO NPs) was achieved by a two-step method, including emulsification and the ionic gelation of chitosan with sodium tripolyphosphate (TPP). The obtained nanoparticles were inspected by dynamic light scattering (DLS) and showed a positively charged surface with a z-average diameter of between 174 and 456 nm. Thermogravimetric analysis (TGA) results showed the three-stage weight loss trends contributing to the water evaporation, chitosan decomposition, and CBLO decomposition. The loading capacity (LC) and encapsulation efficiency (EE) of the CBLO loading in CS@CBLO NPs were 17.77–33.43% and 25.93–50.27%, respectively. The successful encapsulation of CBLO in CS@CBLO NPs was also confirmed by the Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) techniques. The oxidative stability of CBLO and CS@CBLO NPs was monitored by FTIR. As compared to CBLO, CS@CBLO NPs showed less oxidation with a lower generation of hydroperoxides and secondary oxidation products after four weeks of storage. CS@CBLO NPs are composed of two ingredients that are beneficial for health, chitosan and fish oil in a nano powdered fish oil form, with an excellent oxidative stability that will enhance its usage in the functional food and pharmaceutical industries.  相似文献   
133.
This series of paper addressed the quality control of a vertical-type cross-lapper machine, which is used to produce uniform layers of fibers with suitable widths and thicknesses. The nonlinear model of the system was derived, and the corresponding state space representation was obtained. The linearized model based on the equilibrium position of the nonlinear model was generated, and the associated control property was analyzed. The high order linearized model would be reduced to a verified lower order model for control system design. The designed traditional and modern controller could make the crosslapper machine for good card web quality control.  相似文献   
134.
Koi herpesvirus (KHV) is an emerging pathogen of koi and common carp that causes a severe disease and mass mortality of infected fish. The KHV ORF72 protein is an important capsid protein that has been suggested to be a candidate for the development of diagnostic reagents and KHV vaccines. The purpose of this study was to clone and express the KHV ORF72 gene for further preparation of a specific monoclonal antibody (mAb) and to analyse cellular distribution of the viral protein. The mAb 3E1 could specifically recognize the expressed ORF72 protein of transfected cells by indirect immunofluorescence, and the antigenic site recognized by the mAb 3E1 was mapped to the region of N-terminal 124 residues of KHV ORF72. This mAb was further demonstrated to specifically detect the KHV-infected fish tissue by immunohistochemistry, thereby suggesting its high diagnostic potential. In addition, the cellular distribution analysis of the KHV ORF72 protein revealed that the region of amino acid residues 125–247 was related to mitochondrial localization and proliferation. Furthermore, a putative nuclear export signal (NES) of ORF72 at the residues 201–212 was confirmed on the basis of its function associated with NES activity.  相似文献   
135.
Francisella noatunensis subsp. orientalis is a causative agent of systemic granulomatous disease in tilapia. The present study was designed to understand the genetic and phenotypic diversities among Taiwanese Fno isolates obtained from tilapia (n = 17) and green Texas cichlid (Herichthys cyanoguttatus) (n = 1). The enzymatic profiles of the isolates were studied using the API ZYM system. Phylogenetic tree analysis of the 16S rRNA and housekeeping gene and pulsed‐field gel electrophoresis (PFGE) were carried out to determine the genotypic characters of all isolates. The phylogenetic tree showed similarity of 99%–100% nucleotide sequences of 16S rRNA and housekeeping genes compared to the Fno references genes from GenBank database. Comparatively, the results revealed an identical profile of enzymatic and PFGE pattern which was distincted from that of F. philomiragia. To understand the pathogenicity, the isolates were intraperitoneal injected to tilapia the gross lesions were observed concomitant with natural outbreak. Median lethal dose upon Nile tilapia and red tilapia were 9.06 × 103 CFU/fish and 2.08 × 102 CFU/fish, respectively. Thus, our data provide understanding the epidemiology of Taiwanese Fno isolates, and help in development of future control and prevention.  相似文献   
136.
137.
The paper describes some past and current work for the control and regulation of ovarian development. It reports on the induction of ovarian maturation out of season by manipulation of photoperiod and temperature cycle, and recommends conditions of constant temperature control at 21°C and photoperiod of 6L18D for the best results using fish with oocytes in the refractory period. It also recommends salmon pituitary gonadotropin SG-G100 as the best ovulating agent for reliable results, but suggests further research with alternative gonadotropins and steroids. The paper describes some recent progress with the latter.  相似文献   
138.
Excessive inflation of the swim bladder causes immobility and mortality of 12-day old larvae of Mugil cephalus and other marine fish. Increased aeration or mechanical agitation of the water in rearing tanks maintained the larvae below the water surface, and the swim bladder formed and functioned normally. Survival was dramatically increased. Two experimental production tanks, stocked initially with 15 000 and 20 000 larvae, at a density of 5.25 and 7.0/l, respectively, yielded 33.5% and 16.9% juveniles on day 50. Only an outbreak of ciliated parasites prevented both tanks from having survival figures of over 30%.  相似文献   
139.
From mutant pools of two Taiwanese elite japonica cultivars, Tainung 67 and Taikeng 8, we identified 13 mutant lines possessing opaque endosperm with relatively low amylose contents (AC) ranging from 1.5% to 7.1%. Because of different AC, paste viscosities of these 13 mutant lines differed, as revealed by palatability and physicochemical properties. The mutated gene conferring opaque endosperm was isolated from the F2 population of one mutant line, WY1× indica cv. ‘Taichung Sen 17’, by positional cloning, revealing a G3018→A3018 substitution at exon 9 of Waxy leading to a non‐synonymous mutation from alanine to valine. Two additional alleles were identified from the other 12 mutant lines, for which single‐nucleotide substitutions G2708 → A2708 and G3029 → A3029 occurred in exons 8 and 9, leading to non‐synonymous mutations from arginine to histidine and glutamic acid to lysine, respectively. The three novel wx alleles had different effects on grain quality, specifically on eating and cooking quality, and could be applied in rice breeding programmes to develop new low AC varieties by marker‐assisted selection.  相似文献   
140.
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