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81.
To define the interactions required for the filament assembly of differentiation-specific keratins, active copies of mouse hair keratin mHa1 and mHb4 genes were introduced into a rat kangaroo kidney epithelial cell line (PtK2) and a rat stratified squamous epithelial cell line (rat epidermal keratinocyte). In PtK2 transient transfectants, when introduced individually or in combination, mHa1 and mHb4 formed aggregates of ring-like structures of various sizes at the perinuclear region with no evidence of organization into a keratin network. These aggregates altered the distribution of the endogenous keratins and vimentin. In most of the cells carrying the ring-like structures of mHa1 and mHb4 around the nucleus, the endogenous keratin network collapsed and localized around the nucleus. Furthermore, the densely accumulated endogenous keratin surrounded the ring-like aggregates with partial co-localization. However, when transfected into the rat epidermal keratinocytes, mHa1 and mHb4 were able to co-localize with the well-developed cytoskeleton of endogenous keratins. These results showed that, in contrast to keratin pairs K5/K14 and K8/K18, the mHa1/mHb4 pair is unable to develop an extensive keratin network on its own and that there are possible differential abilities among these hair keratins and other keratins to form well-developed cytoplasmic networks.  相似文献   
82.
The colour of meat and rice flour pastes containing known amounts of myoglobin and the colour of intact beef and pork samples were analyzed with tissue spectrophotometer TS-200. The differences in the spectra of myoglobin among three types of derivatives were successfully distinguished with this instrument. In addition, there is a close relationship between IHB value, a parameter for estimating the content of pigments in animal tissues, and myoglobin content in model systems (rice flour paste and meat paste). Especially, the IHB value is proportional to myoglobin content in intact beef and pork meat whose myoglobin is mostly in the state of oxymyoglobin and/or deoxymyoglobin: Y = 208·26 x + 6·72, where y is the IHB value, x is the myoglobin content (%) and R = 0·94.  相似文献   
83.
Metal–support interaction in the catalytic combustion of toluene was studied, using metal oxides with different acid–base properties as supports. The combustion activity over Pd loaded on strong acidic or basic support was lower than over Pd on weak acidic or basic metal oxides. The study of Pd surface with X-ray photoelectron spectroscopy and reaction order measurement showed that the affinity for oxygen changed according to the acid–base property of support. It was considered that the combustion activity of Pd was controlled by the acid–base property of support through an electronic interaction. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
84.
We have researched tetrecyanoquinodimethane (TCNQ) complex salts, developed a new series of organic semiconductive electrolytes (OS-CONs) such as chip-type OS-CONs, and improved our original facilities for mass-production of OS-CONs during the ten years since mass-production was begun. Results of this research and development are presented in this paper. Various new applications of OS-CONs have been developed which fully utilize their properties. This paper also introduces some of these new applications.  相似文献   
85.
Reductions in carrier lifetime, threshold current, and thus turn-on delay time, due to n-type modulation doping, have been experimentally demonstrated in 1.3 μm InGaAsP strained multiquantum well lasers for the first time  相似文献   
86.
Ruthenium catalysts were prepared in different alcohols by a chemical mixing technique, characterised by the preparation of a homogeneous solution containing catalyst components, and the uniform coagulation of the solution through hydrolysis. The technique has the potential for controlling the surface area of the catalysts and for making them porous. The ruthenium catalysts were much more effective for the partial hydrogenation of benzene to cyclohexene (maximum cyclohexene yield, 31.4%) in the absence of any poison such as alkali metal hydroxide or transitional metal sulphate in the reaction solution.  相似文献   
87.
Scanning electrochemical microscopy (SECM) was applied to the immunoassay of leukocidin, which is a toxic protein produced by methicillin-resistant Staphylococcus aureus (MRSA), with the intention of developing and early diagnostic for MRSA infection. An antibody-chip for leukocidin was prepared by self-assembling of anti-leukocidin on a protein A-coated glass substrate. A sample solution containing leukocidin was spotted onto the antibody-chip, followed by labeling with horseradish peroxidase (HRP) via a sandwich method. The reduction current of the oxidized form of ferrocenylmethanol generated by the HRP reaction was monitored to view SECM images of the spot of captured leukocidin. The amplitude of reduction current depended on the concentrations of sample solutions used for making spots. This SECM-based immunoassay detects as low as 5.25 pg mL(-1) leukocidin.  相似文献   
88.
Environmental poisoning is most commonly associated with chronic long-term exposure to toxins rather than to acute exposure. Such repeated exposure to sublethal doses of compounds and elements presents problems in risk assessment. This is primarily because the data are unavailable to describe relationships between dose and effect at lower levels of exposure to toxins. Bioavailability of toxins also presents a problem because the data on bioavailability are sparse and seldom as high as the default of 100% bioavailability commonly used in risk assessment. Examples are presented of two toxins: arsenic as an elemental anthropogenic and geologic poison and ciguatoxin, a polyether ladder compound, as a toxin produced naturally by dinoflagellates. Bioavailability drives the toxicity of arsenic from contaminated sites, whereas tissue accumulation drives the toxicity of ciguatoxin. Considerable benefit is derived from the harmonization of regulatory processes where there is linkage of health and environmental factors in the derivation of credible risk assessment.  相似文献   
89.
This paper discusses requirement and necessity for elimination of recriticality issue in hypothetical core disruptive accident in future fast reactors, and also necessity of a new comprehensive approach of safety research to achieve this objective. A theoretical investigation of the initiating phase consequences in an unprotected loss-of-flow accidents is shown as an example. A generalized model for core behavior is developed in order to clarify a requirement for mechanism to introduce a negative reactivity (controlled material relocation concept) aiming at elimination of recriticality.  相似文献   
90.
False triggering with a ventricular triggered pacemaker and false inhibition with a ventricular inhibited pacemaker were observed in two patients with complete heart block. These arrhythmias were considered to be attributable to false sensing with a demand pacemaker. Both in vitro and in vivo studies were performed to elucidate the mechanism of these false sensings, and the false sensings were reproduced in a series of experiments. Loose contact of the tip of electrodes to myocardial tissue, refractory period, the distance between two electrodes, and the after potential and its dv/dt of pacemaker impulses are considered to affect the performance of demand pacers.  相似文献   
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