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991.
SO2对鲜葡萄采后熏蒸处理的组织解剖研究 总被引:12,自引:0,他引:12
SO2对鲜食葡萄的伤害是渐进性的,且各组织受SO2伤害的情况与其结构及对SO2的敏感性有关。伤害作用起始于膜系统。通过组织解剖观察可见,伤害部位首先表现为细胞壁变性,细胞染色异常,细胞质变性形成颗粒状或物质,从而发生质壁分离现象,并且由于膜系统的破坏,细胞内含物外渗,细胞壁变形呈波齿状,最终完全变形破碎,导致细胞崩溃死亡。 相似文献
992.
INTR0DUCTI0NIn0urprevi0usstudy0fV5andVKfromfouranti-TCSIgEhybrid0masestab-lishedin0urlaboratory,wefoundVKfr0mallfourcl0nesusedfragmentsfromthesamegermlinegenefamilyVK21,andabiasintheuse0fJk1genefragmentwasalsoobserved.Ontheotherhand,thegeneusageofVHwaJsquitediverse.WespeculatedthatinIgEresponsest0TCS,thelightchainmayplayam0reimpor-tantroleinspecificbindingtoallergenicdeterminant0nTCS[1].However,duet0thelimitationofhybrid0matechnology,itisdifficulttoachievealargenumberofanti-TCSI… 相似文献
993.
Human gastric cancer MKN-45 cells were transfected with pULB 3238,a plasmid carrying MVMp MS-1 gene with its original P4 promoter replaced by the glucocorticoid inducible promoter MMTV-LTR.After the integration and expression of NS-1 gene,some of the transfectants died,while others remained alive,but the growth features of survived cells were changed.For further study on the antineoplastic function of parvoviral NS-1 protein in vivo,transgenic mice carrying NS-1 genes were established by conventional method.Among 4 founders,one of them was found to be able to transmit the transgene to around 50% of their offsprings.RT-PCR was performed to indicate the expression of NS-1 gene in transgenic mice and its mRNA appeared in a variety of tissues.The expression of integrated NS-1 gene may correlate with the decreased incidence of tumor induced in vivo by chemical carcinogens. 相似文献
994.
A cDNA coding mutated cecropin CMIV from Bombyx mori was synthesized according to its amino acid sequense using E .coli biased codons .The gene was cloned into the fusion expression vector pEZZ318 and was expressed in E .coli HB101.The fusion protein produced was purified by affinity chromatography to yield 26 mg/L fusion product .The anti-bacterial activities of recombinant cecropin CMIV were recovered after cleavage by chemical method. 相似文献
995.
Using genomic in-situ hybridization (GISH) technique, 7 translocation-addition lines, 6 transloca-tion and translocation-addition lines, 2 ditelosomic addition lines and 1 translocation line were identified from Triticum aestivum L.-Psathyrostachys juncea (Fisch. ) Nevski intergeneric hybrids, of which translocation-addition and translocation and translocation-addition lines were not found in other reports. No substitutions and disomic additions were detected in the hybrids and breakages occurred in all P. juncea chromosomes studied. Results have shown that the improved GISH technique is a rapid and economical method for use in this field. 相似文献
996.
A cDNA coding mutated cecropin CMIV fromBombyx mori was synthesized according to its amino acid sequence usingE. coli biased codons. The gene was cloned into the fusion expression vector pEZZ318 and was expressed inE. coli HB101. The fusion protein produced was purified by affinity chromatography to yield 26 mg/L fusion product. The anti-bacterial
activities of recombinant cecropin CMIV were recovered after cleavage by chemical method. 相似文献
997.
本研究用结扎盲肠及穿刺(CLP)引起败血症。结果证明:大鼠心肌钙通道在早期败血症(ES,CLP后9h)时由心肌轻型囊泡向心肌肌膜转运增多;在晚期败血症(LS,CLP后18h)时由心肌肌膜向心肌轻型囊泡转运增多。败血症时大鼠心肌肌膜和心肌轻型囊泡钙通道的再分布与cAMP依赖性蛋白激酶(PKA),Ca(2+)/钙调素依赖性蛋白激酶(PKM)和蛋白激酶C(PKC)磷酸化作用无关。败血症时大鼠心肌肌膜和心肌轻型囊泡上肾上腺能β-受体、M-胆碱受体和Na+/K+ATPase的变化规律和钙通道的一样,它们可能是败血症时的一种非特异性变化。 相似文献
998.
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1000.
In order to overcome the defects of difficult gene operations in low-copy suicide plasmid pCVD442, Gateway technology was
applied in the construction process of recombinant plasmid for gene knockout in this study. With this improved knockout system,
we inactivatedsitC gene, which is associated with iron transport inShigella flexneri 2a strain 301, to yield the mutant, MTS. The functional detection of the mutant was performed at the level of culture medium,
cell and animal experiment, respectively. The gene expression profiles were compared with DNA microarray between the mutant
and the wild type under iron-restricted conditions. The results showed that MTS grew obviously less well than the wild-type
strains in L broth containing 150 μmol/L iron chelator DIP (2,2′-dipyridyl). Addition of iron or manganese to the cultures
stimulated the growth of MTS to wild-type levels in rich culture medium. In either the experiment on the ability of intracellular
multiplication and cell-to-cell spread in HeLa and U937 cell lines, or the experiment on keratoconjunctivitis in guinea pigs,
MTS showed no obvious changes in virulence compared with the parental strain Sf301. When 65 μmol/L DIP was added to the cultured
HeLa cells, the ability of intracellular multiplication of MTS reduced about 51.6% as compared with that of Sf301. The analysis
of expression profiles under iron-limited condition showed that MTS was more sensitive for the change of iron deficiency than
Sf301. There are 106 more up-regulated genes in MTS than in wild-type strains, which are involved in membrane transportation,
amino acid metabolism and uncategorized function genes, while down-regulated genes are mainly involved in energy and carbohydrate
metabolism. Under low iron conditions, the expression levels of known iron-transport associated genes generally increased.
Additionally, the number of these genes and their increase amplitude in MTS are more than those in Sf301. Together, these
results confirmed that Sit iron-transport system is important for the growth ofShigella. 相似文献