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101.
The in vitro dielectric properties of human fetal organ tissues were measured in the frequency range from 100 kHz to 500 MHz at 24 °C. The dielectric measurements were performed by using a network analyzer (HP4195A) and a coaxial line capacitive sensor. The tested samples, including skin, muscle, heart, lung, liver, kidney, spleen, and brain tissues, were obtained from the legal abortion of five women with 14–16 week gestation periods. © 1996 Wiley-Liss, Inc. 相似文献
102.
Shi Zou Yanqin Du Shunmei Huang Mingfa Chen Xiaoli Yang Sumeng Li Yingshan Chen Meihong Han Jia Li Qing Yu Elisabeth Littwitz-Salomon Hongming Huang Mirko Trilling Shi Liu Rongjuan Pei Jia Liu Baoju Wang Xin Zheng Mengji Lu Ulf Dittmer Shuilin Sun Dongliang Yang Jun Wu 《Journal of virology》2021,95(24)
103.
Leaf blades of the late-sown winter wheat produced the major portion, i.e., more than 60 %, of the total 14C-photosynthates at grain filling, but ear (rachis and glumes) only about 15 %, sheaths about 11 %, and stem internodes about
11 %. The change of plant density in this experiment had little influence on the 14CO2-photoassimilation of the ear (rachis and glumes), flag leaf lamina, sheaths and stem internodes, but markedly affected
photosynthesis of the second, the third and lower leaves. The photosynthetic rate [expressed as specific radioactivity, s-1 kg-1(d.m.)] and the amount of 14CO2 photosynthates decreased significantly in the second, the third and other lower leaves at a high plant density. Upon grain-filling
of the late-sown wheat, the grain was the major importer of photosynthates. Yet partitioning to the stem internodes depended
on the plant density. Stem was the importer of photosynthates at a low plant density, but the exporter at a high plant density.
In plants at a low plant density a fairly large proportion of photosynthates was distributed into the roots. The middle and
lower above-ground parts of the late-sown wheat at a high plant density decreased or lost their function early. As a result,
the plant senesced earlier. However, the grain setting, filling and yielding were restricted. An appropriately low plant density
was suitable for prolonging the function of the middle and lower organs, delaying the senescence of plant, increasing the
source supply for grain filling, and improving the grain yield.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
104.
为了改变传统实验教学的单一模式,同时调动留学生学习的积极性,将开放性实验引入留学生组织学实验教学课程中,通过此举首先有助于提高教学效果;其次增强留学生的综合素质,最后也提高了教师的英语运用能力。在此,我们就初次实施开放性实验教学进行了总结分析,希望与广大同仁交流探讨。 相似文献
105.
Seasonal and spatial diversity of microbial communities in marine sediments of the South China Sea 总被引:1,自引:0,他引:1
This study was conducted to characterize the diversity of microbial communities in marine sediments of the South China Sea
by means of 16S rRNA gene clone libraries. The results revealed that the sediment samples collected in summer harboured a
more diverse microbial community than that collected in winter, Deltaproteobacteria dominated 16S rRNA gene clone libraries from both seasons, followed by Gammaproteobacteria, Acidobacteria, Nitrospirae, Planctomycetes, Firmicutes. Archaea phylotypes were also found. The majority of clone sequences shared greatest similarity to uncultured organisms, mainly from
hydrothermal sediments and cold seep sediments. In addition, the sedimentary microbial communities in the coastal sea appears
to be much more diverse than that of the open sea. A spatial pattern in the sediment samples was observed that the sediment
samples collected from the coastal sea and the open sea clustered separately, a novel microbial community dominated the open
sea. The data indicate that changes in environmental conditions are accompanied by significant variations in diversity of
microbial communities at the South China Sea. 相似文献
106.
107.
108.
Xiaojie Xu Tao Wan Huhu Xin Da Li Hongming Pan Jun Wu Yuan Ping 《The journal of gene medicine》2019,21(7)
The clustered, regularly‐interspaced, short palindromic repeat (CRISPR)‐associated nuclease 9 (CRISPR/Cas9) is emerging as a promising genome‐editing tool for treating diseases in a precise way, and has been applied to a wide range of research in the areas of biology, genetics, and medicine. Delivery of therapeutic genome‐editing agents provides a promising platform for the treatment of genetic disorders. Although viral vectors are widely used to deliver CRISPR/Cas9 elements with high efficiency, they suffer from several drawbacks, such as mutagenesis, immunogenicity, and off‐target effects. Recently, non‐viral vectors have emerged as another class of delivery carriers in terms of their safety, simplicity, and flexibility. In this review, we discuss the modes of CRISPR/Cas9 delivery, the barriers to the delivery process and the application of CRISPR/Cas9 system for the treatment of genetic disorders. We also highlight several representative types of non‐viral vectors, including polymers, liposomes, cell‐penetrating peptides, and other synthetic vectors, for the therapeutic delivery of CRISPR/Cas9 system. The applications of CRISPR/Cas9 in treating genetic disorders mediated by the non‐viral vectors are also discussed. 相似文献
109.
Secretory expression of α single-chain insulin precursor in yeast and its conversion into human insulin 总被引:1,自引:0,他引:1
A synthetic single-chain porcine insulin precursor (PIP) gene and an α-mating factor leader sequence (αMFL) gene obtained by the PCR method are inserted between the promoter and 3'-terminating sequence of the alcohol dehydrogenase gene ADH1 in plasmid pVT102-U to form plasmid pVT102-U/α MFL-PIP. The single-chain insulin precursor is expressed and secreted to the culture medium by Saccharomyces cererisiae transformed by pVT102-U/αMFL-PIP. The precursor is purified and converted into human insulin by tryptic transpeptidation. The purified human insulin is fully active and can be crystallized. The overall yield of human insulin is 25 mg per liter of culture medium. 相似文献
110.
Sven-Erik Larsson Romy Larsson Qiuxia Zhang Hongming Cai P. ?ke ?berg 《European journal of applied physiology and occupational physiology》1995,71(6):493-498
Mental stress was induced by the Stroop colour word task (CW task) and the effects on the micro-circulation and electromyography (EMG) in the upper portion of the trapezius muscle were studied during a series of fatiguing, standardized static contractions. A lowered blood flow of the skin recorded continuously by laser-Doppler flowmetry (LDF) was used as a stress indicator in addition to an elevated heart rate. Muscle blood flow was recorded continuously by LDF using a single optical fibre placed inside the muscle, and related to surface EMG. A group of 20 healthy women of different ages was examined. Recordings were made during a 50-min period in the following sequence: a 10-min series of alternating 1-min periods of rest and stepwise increased contraction induced by keeping the arms straight and elevated at 30, 60, 90 and 135° with a 1-kg load carried in each hand; a 10-min recovery period without load; a repeated contraction series with simultaneous performance of the CW task; a second 10-min recovery period, and a second contraction series without CW task. Signal processing was done on line by computer. The LDF and root mean square (rms)-EMG values were calculated, as well as the EMG mean power frequency (MPF) for fatigue. The CW-task added to the contraction series caused an increase in the heart rate accompanied by a decrease in the blood flow to the skin and a 30% increase in the blood flow in the exercising muscle. Both returned to normal during the subsequent recovery period and showed normal levels during the final contraction series without CW. The rms-EMG showed a 20% increase that persisted during the final contraction series performed without CW. There was no influence on MPF. This CW has previously been shown to evoke an increased secretion of adrenaline from the adrenal medullae to the blood. The increased blood flow in the exercising muscle would therefore appear to have been caused by -adrenoceptor vasodilatation, and the fall in the blood flow in the skin by -adrenoceptor vasoconstriction. The findings may have implications for work situations characterized by repetitive static loads to the shoulder muscles and psychological stress. 相似文献