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151.
Twenty species of Aspergillus and their teleomorphs were isolated from naturally fermented soybean pastes collected in 42 regions of China. Of which A. tubingensis, A. flavus, A. niger, A. ochraceus, A. candidus and A. fumigatus were predominant. The high frequency of A. flavus from the samples indicates that the traditional making method of soybean paste might possibly be harmful to food safety. Some Aspergillus species or strains isolated from the traditional food samples may be hopeful of using in pure leaven making and industrial production of soybean paste with special flavor. 相似文献
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153.
为深化研究血管生成抑制剂canstatin的生物学性能和用于肿瘤生物治疗的可能性,针对canstatin cDNA序列设计引物,运用逆转录聚合酶链反应(RT-PCR)从人胚肝组织中钓取canstatin cDNA,将其克隆入pMND18-T载体中,通过酶切鉴定出重组体并测序分析,结果表明,获得684bp人canstatin基因,成功构建人canstatin cDNA 克隆载体pMB18-T/canstatin,为进一步进行canstatin蛋白表达及活性研究奠定了基础。 相似文献
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155.
S A Gaffar J A Braatz K H Kortright G L Princler K R McIntire 《The Journal of biological chemistry》1979,254(6):2097-2102
A human lung tumor-associated antigen was purified to homogeneity from a crude cell-free extract of a human lung adenocarcinoma using standard biochemical procedures. In order to facilitate monitoring the recovery of antigen, trace amounts of previously purified and radioiodinated antigen from another lung tumor were added to the crude extract. The purified antigen was a glycoprotein and contained sialic acid. The antigen had a molecular weight of 76,000 and appeared to contain three subunits, each with a molecular weight of 25,000. The antigen had the following physical properties: Stokes radius, 39.4 A; S20,w, 4.24 S; D20,w, 5.15 x 10(-7) cm2 S-1; and a frictional ratio of 1.40. In addition, the purified, radioiodinated antigen retained complete immune reactivity since it could be quantitatively precipitated with specific immune serum. All of these properties were in close agreement with the properties of another antigen which was purified from a separate human lung tumor. Thus, it appeared from the biochemical and immunochemical criteria presented in this report that a common and identical antigen was isolated from two distinct human lung tumor extracts. 相似文献
156.
目的:将非药物性干预措施与传统药物方法治疗极低出生体重儿喂养不耐受的临床疗效进行观察比较。方法:选取哈尔滨医科大学附属第二医院2011年1月至2013年4月出生的喂养不耐受极低出生体重儿110例。按入院顺序随机分为药物治疗组(MED)55例、非药物治疗组(NON-MED)55例。药物治疗组采用红霉素;非药物治疗组采用腹部按摩法与非营养性吸吮。结果:两组患儿经治疗后,MED组腹胀消失天数(4.4±0.5)、呕吐天数(2.2±0.5)、每日呕吐次数(3.5±0.8)、胃潴留量占每日喂养量(18.3±0.8)、达全肠道喂养天数(8.2±0.7);NON-MED组腹胀消失天数(3.7±0.1)、呕吐天数(1.9±0.6)、每日呕吐次数(2.8±0.1)、胃潴留量占每日喂养量(12.6±0.4)、达全肠道喂养天数(6.1±0.3)。各项治疗指标的对比中,差异均有统计学意义(P0.05)。MED组治疗有效率76.4%;NON-MED组治疗有效率83.6%。结论:非药物性干预措施可有效改善极低出生体重儿喂养不耐受。 相似文献
157.
我国热带地区是外来入侵物种发生与危害的重灾区,近年来外来有害昆虫入侵所引发的生物灾害及生态安全问题日趋严峻。在海南省、广东省、广西壮族自治区、云南省、福建省外来入侵昆虫的调查结果及文献资料的基础上,整理分析了中国热带地区外来入侵昆虫的种类构成、分布、原产地及首次发现地。据统计,2000-2014年我国热带地区的外来入侵昆虫种类共计23种,隶属于6目11科,数量最多的为半翅目(13种,56.52%),其中以粉蚧科和粉虱科居多;热带地区的外来入侵昆虫在不同地区之间的物种数量差异较大,其中海南省最多(19种,82.61%),其后依次为广东省(16种,69.57%)、云南省(14种,60.87%)、广西壮族自治区(12种,52.17%),而福建省最少(9种,占39.13%);在入侵我国热带地区的外来有害昆虫中,原产于亚洲、北美洲的种类最多均为6种,占26.09%,南美洲占21.74%,而从非洲、大洋洲、欧洲传入的分别占8.70%、4.35%、4.35%;外来入侵昆虫的首次发现地位于广东省的有9种,占39.13%,出现在海南省和云南省的各占30.43%、21.74%,出现在广西壮族自治区的为8.70%。阐明我国热带地区外来有害昆虫的种类特征及入侵现状,可为该地区外来入侵昆虫的监测与防控提供一定的依据。 相似文献
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159.
Paul M. Sanders Anhthu Q. Bui Koen Weterings K. N. McIntire Yung-Chao Hsu Pei Yun Lee Mai Thy Truong T. P. Beals R. B. Goldberg 《Sexual plant reproduction》1999,11(6):297-322
We identified Arabidopsis thaliana sterility mutants by screening T-DNA and EMS-mutagenized lines and characterized several male-sterile mutants with defects
specific for different anther processes. Approximately 44 and 855 sterile mutants were uncovered from the T-DNA and EMS screens,
respectively. Several mutants were studied in detail with defects that included the establishment of anther morphology, microspore
production, pollen differentiation, and anther dehiscence. Both non-dehiscencing and late-dehiscencing mutants were identified.
In addition, pollenless mutants were observed with either apparent meiotic defects and/or abnormalities in cell layers surrounding
the locules. Two mutant alleles were identified for the POLLENLESS3 locus which have defects in functional microspore production that lead to the degeneration of cells within the anther locules.
pollenless3–1 contains a T-DNA insertion that co-segregates with the mutant phenotype and pollenless3–2 has a large deletion in the POLLENLESS3 gene. The POLLENLESS3 gene has no known counterparts in the GenBank, but encodes a protein containing putative nuclear localization and protein-protein
interaction motifs. The POLLENLESS3 gene was shown recently to be the same as MS5, a previously described Arabidopsis
thaliana male-sterility mutant. Three genes were identified in the POLLENLESS3 genomic region: GENEY, POLLENLESS3, and β9-TUBULIN. The segment of the Arabidopsis
thaliana genome containing the POLLENLESS3 and β9-TUBULIN genes is duplicated and present on a different chromosome. Analysis of the POLLENLESS3 expression pattern determined that the 1.3-kb POLLENLESS3 mRNA is localized specifically within meiotic cells in the anther
locules and that POLLENLESS3 mRNA is present only during late meiosis.
Received: 15 October 1998 / Revision accepted: 19 November 1998 相似文献
160.