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981.
中国原花蝽属新种及新纪录(半翅目:花蝽科)   总被引:1,自引:0,他引:1  
本文记载中国花蝽科原花蝽属Anthocoris Fallen新种6个,计为:黑角原花蝽A.atricarnis sp.n.(模式产地:云南),哀牢原花蝽A.ailaoanus sp.n.(模式产地:云南),杨氏原花蝽A.yangi sp.n.(模式产地:云南),刺突原花蝽A.armatus sp.n.(模式产地:云南),萧氏原花蝽A.hsiaoi sp.n.(模式产地:四川、陕西),秀原花蝽A.concinnus sp.n.(模式产地:西藏)。文章并记录此属的3个中国新记录种;并为已被占用的A.elongatus Zheng 1982命以新名:A.longiusculus nom.nov.  相似文献   
982.
The gene for Huntington disease, a neurodegenerative disorder with autosomal dominant inheritance, has been localized to the terminal portion of the short arm of human chromosome 4 (4p16.3) by linkage analysis. Since eventual isolation of the gene requires the application of high-resolution genetic analysis coupled with long-range DNA mapping and cloning techniques, we have constructed a physical map of the chromosomal region 4p16.3 using more than 20 independently derived probes. We have grouped these markers into three clusters which have been ordered and oriented by genetic and somatic cell genetic mapping information. The mapped region extends from D4S10 (G8) toward the telomere and covers minimally 5 Mb.  相似文献   
983.
新生牛肝细胞生长因子是一种热稳定、蛋白酶及酸化(pH<1.5)敏感的蛋白质或多肽。研究结果表明,它可促进肝来源的细胞系的DNA合成,但不能刺激非肝来源细胞系的DNA合成。它还可提高某些化合物(CCl_4,D-Gal)引起的急性肝衰竭小鼠的存活率。  相似文献   
984.
为揭示毛竹(Phyllostachysedulis)快速生长期茎秆中的光合碳同化特征及其在不同节间的变化规律,以毛竹笋竹茎秆为材料,测定不同节间光合色素含量、核酮糖-1,5-二磷酸羧化酶/加氧酶(Rubisco)、磷酸烯醇式丙酮酸羧化酶(PEPC)、苹果酸脱氢酶(NADP-MDH)、NADP-苹果酸酶(NADP-ME)、磷酸烯醇式丙酮酸羧激酶(PEPCK)以及丙酮酸磷酸双激酶(PPDK)活性。结果显示,茎秆中叶绿素a、叶绿素b以及类胡萝卜素含量随节间升高均呈下降趋势,叶绿素a/b比值呈逐渐上升趋势;随着节间的升高,茎秆中Rubisco、PEPC和PPDK活性在第1–10节间显著下降,之后酶活性降幅逐渐减缓;NADP-ME活性在第1–13节间呈显著下降趋势,之后酶活性趋于平稳;NADP-MDH活性在第1–25节间显著下降。PEPC/Rubisco活性比值随节间升高而不断增加,其范围介于18.37–65.09之间,明显大于典型C3植物中的活性比值。上述结果表明,茎秆不同节间的光合碳同化能力存在明显差异,中、下部节间生长相对较快;茎秆中存在多种C4酶且活性较高,这为此时期茎秆中存在C4光合途径提供了有力证据。  相似文献   
985.
Tauopathies, such as Alzheimer's disease, are characterized by intracellular aggregates of insoluble Tau proteins. Originally described as a microtubule binding protein, recent studies demonstrated additional physiological roles for Tau. The fact that a single protein can regulate multiple cellular functions has posed challenge in terms of understanding mechanistic cues behind the pathology. Here, we used tandem-affinity purification methodology coupled to mass spectrometry to identify novel interaction partners. We found that Tau interacts with DDX6, a DEAD box RNA helicase involved in translation repression and mRNA decay as well as in the miRNA pathway. Our results demonstrate that Tau increases the silencing activity of the miRNA let-7a, miR-21 and miR-124 through DDX6. Importantly, Tau mutations (P301S, P301L) found in the inherited tauopathies, frontotemporal dementia and parkinsonism linked to chromosome 17, disrupt Tau/DDX6 interaction and impair gene silencing by let-7a. Altogether, these data demonstrated a new unexpected role for Tau in regulating miRNA activity.  相似文献   
986.
Methane production by methanogens in wetland is recognized as a significant contributor to global warming. Spartina alterniflora (S. alterniflora), which is an invasion plant in China’s wetland, was reported to have enormous effects on methane production. But studies on shifts in the methanogen community in response to S. alterniflora invasion at temporal and spatial scales in the initial invasion years are rare. Sediments derived from the invasive species S. alterniflora and the native species Phragmites australis (P. australis) in pairwise sites and an invasion chronosequence patch (4 years) were analyzed to investigate the abundance and community structure of methanogens using quantitative real-time PCR (qPCR) and Denaturing gradient gel electrophoresis (DGGE) cloning of the methyl-coenzyme M reductase A (mcrA) gene. For the pairwise sites, the abundance of methanogens in S. alterniflora soils was lower than that of P. australis soils. For the chronosequence patch, the abundance and diversity of methanogens was highest in the soil subjected to two years invasion, in which we detected some rare groups including Methanocellales and Methanococcales. These results indicated a priming effect at the initial invasion stages of S. alterniflora for microorganisms in the soil, which was also supported by the diverse root exudates. The shifts of methanogen communities after S. alterniflora invasion were due to changes in pH, salinity and sulfate. The results indicate that root exudates from S. alterniflora have a priming effect on methanogens in the initial years after invasion, and the predominate methylotrophic groups (Methanosarcinales) may adapt to the availability of diverse substrates and reflects the potential for high methane production after invasion by S. alterniflora.  相似文献   
987.

Background

The limitations of conventional sperm analyses have highlighted the need for additional means of evaluating sperm quality.

Methods

In a study of a cohort of 245 men with known conventional sperm parameters, one-dimensional PAGE was used to monitor protein content and quality in samples from individual ejaculates.

Results

The sperm protein content varied markedly from sample to another, especially in the high-molecular-weight range. The intensity of the 80–110 kDa bands was correlated with progressive motility (r?=?0.15, p?=?0.015) and was significantly higher (p?=?0.0367) in the group of men with conventional parameters above the World Health Organization’s 2010 reference values than in the group with at least one subnormal parameter (i.e. semen volume, sperm concentration, sperm count per ejaculate, progressive motility, proportion of normal forms or multiple anomaly index below the lower reference value). Using mass spectrometry, the 80–110 kDa bands were found to correspond primarily to three proteins from the flagellum’s fibrous sheath: A-kinase anchor protein 4, A-kinase anchor protein 3, and spermatogenic cell-specific type 1 hexokinase.

Conclusion

One-dimensional PAGE constitutes a simple, rapid, reliable, inexpensive method for analyzing proteins associated with sperm motility in individual human ejaculates.
  相似文献   
988.
Multi-drug resistant uropathogens are responsible for urinary tract infections. The antibacterial activity of seven essential oils, oregano, thyme, clove, arborvitae, cassia, lemongrass, tea tree) was investigated by agar diffusion method, followed by determination of minimum inhibitory (MIC) and bactericidal (MBC) concentrations against five multidrug resistant isolates namely Pseudomonas aeruginosa, Escherichia coli, Enterobacter cloaceae, Morganella morganii, Proteus mirabilis. Oregano, thyme, cassia had antibacterial activity with inhibition zones ranging 25–39 mm; clove, arborvitae, tea tree and lemongrass 12–15 mm. The essential oils showed antibacterial activities with MICs ranged from 0.005% (w/v) to 0.5% (w/v). Thyme had the same MIC and MBC on all strains. The effects of the vapors of the essential oils were also tested by placing the oils on the underside of the Petri dish lid. Thyme, oregano and cassia essential oils strongly inhibited the growth of the clinical strains of bacteria tested in vapor phase. This study demonstrates the potential of investigated essential oils as natural alternatives for further application in hospital therapies in order to retard or inhibit the bacterial growth. For the first time antibacterial effects of essential oils (clove, arborvitae, tea tree, lemongrass, and cassia) were evaluated against Enterobacter cloaceae and Morganella morganii clinical isolates.  相似文献   
989.
990.
Ke  Zhixin  Tan  Yehui  Huang  Liangmin  Liu  Huajian  Liu  Jiaxing  Jiang  Xin  Wang  Junxing 《Coral reefs (Online)》2018,37(3):919-927
Coral Reefs - Nutrients’ concentration, phytoplankton biomass, and primary productivity were investigated in six coral atolls in the central South China Sea during the southwest monsoon in...  相似文献   
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