共查询到20条相似文献,搜索用时 15 毫秒
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Yvan Touitou Michael H. Smolensky Francesco Portaluppi 《Chronobiology international》2013,30(6):1083-1096
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目的建立呼肠孤病毒Ⅲ型(Re03)RT—PCR检测方法,应用于实验动物及人用动物源性材料及生物制品外源Re03的检测。方法根据已发表的呼肠孤病毒Ⅲ型(Re03)M1基因序列,设计合成引物。提取Re03细胞毒RNA,以其为模板,进行PCR扩增。优化反应条件,进行特异性、敏感性、重复性试验。结果建立的Re03RT—PCR检测方法特异、敏感、稳定。以Re03RNA逆转录产物为模板,所能检测RNA最小模板浓度为0.42pg/μL,可检测病毒最小滴度为10^-9/mL。结论建立的呼肠孤病毒Ⅲ型(Re03)RT—PCR检测方法可用于实验动物及人用动物源性材料及生物制品外源Re03的检测。 相似文献
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Striefel S 《Applied psychophysiology and biofeedback》2001,26(1):39-59
La Vaque and Rossiter made a strong, supported argument that it is unethical to use a no treatment control group in a research study if a known, effective treatment is available. Their argument is based on the supposition that the Declaration of Helsinki is the ethical world standard for research with humans. Their argument appears to be straightforward, but is not simple to apply. The issues are very complex, include issues not discussed in their argument, and can lead to a different conclusion as pointed out in this paper. The World Medical Association developed the Declaration of Helsinki as one of their official policies. The Declaration of Helsinki, however, is not accepted as the world ethical standard, as demonstrated by its lack of adoption by many professional associations or even by the United States Federal Government. Perhaps it is not mentioned because its ethical provisions are aspirational rather than mandatory as implied by La Vaque and Rossiter. Researchers and clinicians should also be aware of other ethical issues not directly discussed in the La Vaque and Rossiter paper. The Belmont Report is the basis for the ethical protection of human research subjects for at least 17 federal agencies and does not mention the Declaration of Helsinki. The Belmont Report mentions several ethical principles that form the basis for informed consent, risk/benefit assessment, confidentiality of data, subject selection, Institutional Review Boards, and other protections needed when doing research with human subjects. At least 2 of these core principles have direct implications to the discussion related to the use of placebo controls. The ethical principle of fidelity is also important in guiding research activities with human subjects. Researchers should be familiar with the La Vaque and Rossiter argument, the Belmont Report, and the federal policies developed to implement the provisions of that report, for example, Regulation 45 CFR 46. 相似文献
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Orr S Alexandre E Clark B Combes R Fels LM Gray N Jönsson-Rylander AC Helin H Koistinen J Oinonen T Richert L Ravid R Salonen J Teesalu T Thasler W Trafford J Van Der Valk J Von Versen R Weiss T Womack C Ylikomi T 《Cell and tissue banking》2002,3(2):133-137
This is a report of a workshop held on the establishment of human research tissue banking which was held in Levi, Finland
21–24 March 2002.There were 21 participants from 7 European countries. This meeting was attended by representatives from academia,
research tissue banks and from the Biotech and Pharmaceutical Industries. The principal aim of the workshop was to find a
way to progress the recommendations from ECVAM workshop 44 (ATLA 29, 125–134,2001) and ECVAM workshop 32 (ATLA 26, 763–777,
1998). The workshop represented the first unofficial meeting of the European Network of Research Tissue Banks (ENRTB) steering
group. It is expected that in the period preceding the next workshop the ENRTB steering group will co-ordinate the ethical,legislative
and organisational aspects of research tissue banking. Key issues dealt with by the Levi workshop included the practical aspects
of sharing expertise and experiences across the different European members. Such collaboration between research tissue banks
and end users of such material seeks to ultimately enable shared access to human tissue for medical and pharmaco-toxicological
research while maintaining strict adherence to differences in legal and ethical aspects related to the use of human tissue
in individual countries.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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The circadian leaf movement of Oxalis regnellii Mig, has been investigated. The three leaflets of a stalk were normally synchronized, and under the experimental conditions chosen they showed a period of 26.2 ± 0.1 h. Cutting off one or two leaflets led to a successive decrease of the period length (25.7 ± 0.1 and 25.1 ± 0.3 h resp.). It was possible to phase shift the leaf movements by mechanical means (advance of 1.6 ± 0.3 h).
Lithium ions, added permanently to the transpiration stream, increased the period length of the leaf movements by more than one hour (with 10 m M Li+ ). A 24 h pulse of 20 m M LiCl caused a permanent 2–3 h phase delay of the circadian rhythm. Four-h pulses, on the other hand, provoked only transient phase delays, the magnitude being dependent on the phase of application. Lithium concentrations were determined for different regions of leaves and pulvini. It was shown that leaf segments had considerably lower concentrations than pulvini. No significant difference in the lithium concentration was observed between the upper and lower part of pulvini.
In the light leaf position was strongly correlated with water uptake and the consequences for applications of substances to the circadian system via the transpiration stream is discussed. A simple model of the oscillatory system and reactions connected to it is discussed. 相似文献
Lithium ions, added permanently to the transpiration stream, increased the period length of the leaf movements by more than one hour (with 10 m M Li
In the light leaf position was strongly correlated with water uptake and the consequences for applications of substances to the circadian system via the transpiration stream is discussed. A simple model of the oscillatory system and reactions connected to it is discussed. 相似文献
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G. V. Iyengar 《Biological trace element research》1987,12(1):263-295
This report attempts to formulate reference ranges of elemental concentrations for 15 trace elements in selected human tissues
and body fluids.
A set of samples consisting of whole blood, blood serum, urine, milk, liver, and hair were chosen and considered for 15 elements
of biological significance: As, Cd, Co, Cr, Cu, F, Fe, I, Hg, Mn, Mo, Ni, Pb, Se, and Zn. The results represent wholly or
partially data received from 40 countries of the global regions of Africa, Asia, Europe, North, South, and Central America,
Australia, and New Zealand.
This survey, even if qualitative, has been useful in demonstrating certain trends of trace-element scenarios around the world.
It is of course recognized that both diet and environment exert a strong influence on the distribution pattern of several
elements, such as As, Cd, Mn, Pb, Se, and Zn. A limited comparison of the available information on soil status of different
countries reflected some interesting associations for elements, such as Mn and Zn.
Importantly, this study revealed that only a few countries were in a position to identify a reasonable amount of data on samples
requested for this project. Regretably, for a number of countries, any dependable data for even such essential elements as
Cu, Fe, and Zn were not available.
In view of the nutritional importance of many elements, the time is ripe for concerted efforts by intergovernmental agencies
to initiate investigations or commission task forces/projects to generate reliable reference data for selected global regions,
which sadly lack data of any kind at present. 相似文献
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Dielectric behavior of water in biological solutions: studies on myoglobin, human low-density lipoprotein, and polyvinylpyrrolidone 总被引:1,自引:0,他引:1
E H Grant V E McClean N R Nightingale R J Sheppard M J Chapman 《Bioelectromagnetics》1986,7(2):151-162
The dielectric behavior of the aqueous solutions of three widely differing macromolecules has been investigated: myoglobin, polyvinylpyrrolidone (PVP), and human serum low-density lipoprotein (LDL). It was not possible to interpret unambiguously the dielectric properties of the PVP solution in terms of water structure. The best interpretation of the dielectric data on the myoglobin and LDL solutions was that, in both cases, the macromolecule attracts a layer of water of hydration one or two water molecules in width. For LDL, this corresponds to a hydration factor of only 0.05 g/g, whereas for myoglobin the figure is nearer 0.6 g/g. With myoglobin, part of the water of hydration exhibits its dispersion at frequencies of a few GHz, and the rest disperses at lower frequencies, perhaps as low as 10-12 MHz. The approximate constancy of the width of the hydration shell for two molecules as dissimilar in size as LDL and myoglobin confirms that the proportion of water existing as water of hydration in a biological solution depends critically on the size of the macromolecules as well as on their concentration. 相似文献
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Photon reemission in the ultraweak intensity range that is observed after irradiation of cell suspensions with light, reveals
characteristic differences between normal human amnion cells and transformed wish cells from the same parental tissue. The
reemission kinetics, approximated best by a hyperbolical process, were studied as a function of cell density, showing that:
malignant Wish cells have a photon storage capacity that is not improved by increasing the cell density; and that normal amnion
cells exhibit a photon storage capacity that strongly increases with increasing cell density. The interpretation of this effect
and the nature of the emitter are discussed. 相似文献
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Farida Begum Noor Barak Almandil Muhammad Arif Lodhi Khalid Mohammed Khan Abdul Hameed Shahnaz Perveen 《Bioorganic & medicinal chemistry》2019,27(6):1009-1022
This study deals with the synthesis of benzophenone sulfonamides hybrids (1–31) and screening against urease enzyme in vitro. Studies showed that several synthetic compounds were found to have good urease enzyme inhibitory activity. Compounds 1 (N′-((4′-hydroxyphenyl)(phenyl)methylene)-4′′-nitrobenzenesulfonohydrazide), 2 (N′-((4′-hydroxyphenyl)(phenyl)methylene)-3′′-nitrobenzenesulfonohydrazide), 3 (N′-((4′-hydroxyphenyl)(phenyl)methylene)-4′′-methoxybenzenesulfonohydrazide), 4 (3′′,5′′-dichloro-2′′-hydroxy-N′-((4′-hydroxyphenyl)(phenyl)methylene)benzenesulfonohydrazide), 6 (2′′,4′′-dichloro-N′-((4′-hydroxyphenyl)(phenyl)methylene)benzenesulfonohydrazide), 8 (5-(dimethylamino)-N′-((4-hydroxyphenyl)(phenyl)methylene)naphthalene-1-sulfono hydrazide), 10 (2′′-chloro-N′-((4′-hydroxyphenyl)(phenyl)methylene)benzenesulfonohydrazide), 12 (N′-((4′-hydroxyphenyl)(phenyl)methylene)benzenesulfonohydrazide) have found to be potently active having an IC50 value in the range of 3.90–17.99?µM. These compounds showed superior activity than standard acetohydroxamic acid (IC50?=?29.20?±?1.01?µM). Moreover, in silico studies on most active compounds were also performed to understand the binding interaction of most active compounds with active sites of urease enzyme. Structures of all the synthetic compounds were elucidated by 1H NMR, 13C NMR, EI-MS and FAB-MS spectroscopic techniques. 相似文献
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Konstantin N. Bulygin Yulia S. Bartuli Alexey A. Malygin Dmitri M. Graifer Ludmila Yu. Frolova Galina G. Karpova 《RNA (New York, N.Y.)》2016,22(2):278-289
Translation termination in eukaryotes is mediated by release factors: eRF1, which is responsible for stop codon recognition and peptidyl-tRNA hydrolysis, and GTPase eRF3, which stimulates peptide release. Here, we have utilized ribose-specific probes to investigate accessibility of rRNA backbone in complexes formed by association of mRNA- and tRNA-bound human ribosomes with eRF1•eRF3•GMPPNP, eRF1•eRF3•GTP, or eRF1 alone as compared with complexes where the A site is vacant or occupied by tRNA. Our data show which rRNA ribose moieties are protected from attack by the probes in the complexes with release factors and reveal the rRNA regions increasing their accessibility to the probes after the factors bind. These regions in 28S rRNA are helices 43 and 44 in the GTPase associated center, the apical loop of helix 71, and helices 89, 92, and 94 as well as 18S rRNA helices 18 and 34. Additionally, the obtained data suggest that eRF3 neither interacts with the rRNA ribose-phosphate backbone nor dissociates from the complex after GTP hydrolysis. Taken together, our findings provide new information on architecture of the eRF1 binding site on mammalian ribosome at various translation termination steps and on conformational rearrangements induced by binding of the release factors. 相似文献
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Charles Yarish Peter Edwards Stephen Casey 《Journal of experimental marine biology and ecology》1980,47(3):235-249
The effects of varying salinity and calcium and potassium concentrations on the growth of two species of estuarine Rhodophyta, Bostrychia radicans Montagne and Caloglossa lepricurii (Montagne) J. Agardh, were examined in unialgal culture. Inocula of settled tetraspores on glass coverslips were incubated in six concentrations of potassium (0. 100, 200, 300, 400 and 500 mg/l) at five salinities (0, 5, 15, 25, and 35%) in the presence of calcium. Growth responses of each alga were determined from the average cell number of 75 tetrasporelings after 4 days in Ott's synthetic sea-water medium. The concentrations of dissolved potassium and calcium in sea water along a salinity gradient in an estuary were determined with atomic absorption spectrophotometry. Four-day-old tetrasporeling of Bostrychia and Caloglossa demonstrated growth over wide ranges of potassium concentrations with growth maxima at 400 500 and 200 400 mg/l, at the optimal salinities for growth of 25 and 15%, respectively. These studies indicate also that the presence of calcium is essential for appreciable growth of both species at each salinity and the effects of variations in potassium are dependent upon the presence of calcium. The abundance of both species in the Mullica River estuary. New Jersey, appears to be a response to a total osmotic effect along the salinity gradient because sufficient levels of the major cations are present. However, the upper limit of both species towards the head of the Mullica River estuary may be determined by combinations of low salinity and low levels of dissolved calcium and potassium rather than by low salinity alone. 相似文献
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S. A. Tarafdar S. Akhter S. Kar S. K. Biswas A. H. Khan 《Biological trace element research》1987,12(1):121-131
Proton-induced X-ray emission (PIXE) method was employed to study the concentration of heavy elements in betel leaves, betel
nuts, and mineral lime consumed in Bangladesh. The samples were collected from different parts of Bangladesh and analyzed
by the thicktarget external beam technique of the PIXE method. The samples were exposed to the proton beam as 1-mm thick pellets
and irradiated with 2.0-MeV protons having 20-nA beam intensity. The concentration of some 15 elements (K, Ca, Ti, V, Cr,
Mn, Fe, Ni, Cu, Zn, Se, Br, Rb, Sr, and Pb) was measured by comparison with a calibration curve constructed from the NBS orchard
leaf standard SRM 1571. The validity of the procedure has been established by comparative measurements of Cu and Zn with atomic
absorption spectrophotometry. The significance of the results is discussed in view of their implications in health and disease. 相似文献
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Zaibao Zhang Yilin Zhao Xiaobing Feng Zhaoyi Luo Shuwei Kong Chi Zhang Andong Gong Hongyu Yuan Lin Cheng Xiangnan Wang 《Genomics》2019,111(4):619-628
Reactive oxygen species (ROS) are versatile signaling molecules in sensing stresses and play critical roles in signaling and development. Plasma membrane NADPH oxidases (NOXs) are key producers of ROS, and play important roles in the regulation of plant-pathogen interactions. Here, we performed a comprehensive analysis of the NOX gene family in the soybean genome (Glycine max) and 17 NOX (GmNOX) genes were identified. Structural analysis revealed that the GmNOX proteins in soybean were as conserved as those in other plants. 8 duplicated gene pairs were formed by a Glycine-specific whole-genome duplication (WGD) event approximately 13 million years ago (Mya). The Ka/Ks ratios of GmNOX genes ranged from 0.04 to 0.28, suggesting that the GmNOX family had undergone purifying selection in soybean. Gene expression patterns showed different expression of these duplicate genes, suggesting that the GmNOXs were retained by substantial subfunctionalization during the soybean evolutionary processes. Subsequently, the expression of GmNOXs in response to drought and phytohormones were characterized via qPCR. Importantly, four GmNOXs showed strong expression in nodules, pointing to their probable involvement in nodulation. Thus, our results shed light on the evolutionary history of this family in soybean and contribute to the functional characterization of GmNOX genes in soybean. 相似文献
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Hongjin Bai Pengcheng Cui Chuanli Zang Shengkun Li 《Bioorganic & medicinal chemistry letters》2019,29(23):126718
The first enantioselective total synthesis of the antifungal natural product (indole-N-isoprenyl)-tryptophan-valine diketopiperazine 5 was accomplished. Four stereoisomers of 5 were intentionally prepared, and the (R, R)-isomer is more favorable in enhancing the antifungal bioactivity. Divergent structural optimization of this attractive model was conducted from the chiral pool amino acids. Fine-tuning of the structure protruded the broad-spectrum antifungal 6b, which also showed good preventative efficacy against Sclerotinia scleotiorum. Compound 5d could accelerate both hypocotyl elongation and root growth of Eclipta prostrata even at the concentration of <2.5 ppm. This unique and easily accessible scaffold will be of prime importance in achieving agrochemical candidates with the novel scaffold. 相似文献