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51.
Thermoregulatory responses at ambient temperatures of 20 and 10° C in six male subjects wearing two different kinds of clothing were compared between summer and winter. The two different kinds of clothing were one insulating the upper half of the body lightly and the lower half of the body heavily (clothing A, the weight in the upper and lower halves of the body being, respectively, 489 g and 1278 g) and the other insulating the upper half of the body heavily and the lower half of the body lightly (clothing B: 1212 g and 559 g). The major findings are summarized as follow. (i) Rectal temperature was kept significantly higher in clothing B than in clothing A both in summer and winter. (ii) The fall of rectal temperature was significantly greater in summer than in winter in both types of clothing. (iii) Mean skin temperatures and skin temperatures in the face, chest, thigh and leg were significantly lower atT
a of 10° C in summer than in winter in clothing A, while skin temperatures in the face and thigh were also significantly lower atT
a of 10° C in summer than in winter in clothing B. (iv) Metabolic heat production was higher in summer than in winter at 20 and 10° C in both types of clothing. (v) The subjects felt cooler and colder toT
a of 10° C in summer than in winter in both types of clothing. These different responses occurring between summer and winter are discussed mainly in terms of total conductance and dry heat loss. 相似文献
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Usuda K Wada Y Ishimaru Y Kobayashi T Takahashi M Nakanishi H Nagato Y Mori S Nishizawa NK 《Plant biotechnology journal》2009,7(1):87-95
Nicotianamine (NA), a metal chelator ubiquitous in higher plants, serves as an antihypertensive substance in humans. To engineer a novel antihypertensive rice that contains larger amounts of NA, the barley NA synthase gene, HvNAS1 , was introduced into rice via Agrobacterium -mediated transformation. The introduced HvNAS1 was driven by pGluB-1 , which induces strong gene expression in the endosperm of rice seeds. The NA content in transgenic rice seeds was up to fourfold greater than that in non-transgenic rice seeds. The Cre/ loxP DNA excision (CLX) system was used to remove the selectable marker gene for antibiotic resistance. Furthermore, the transgenic rice was crossed with a cleistogamous mutant to prevent gene transfer via pollen dispersal. These two modifications may minimize public concern with regard to the use of this transgenic rice. 相似文献
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Development of a highly sensitive chemiluminescent assay for hydrogen peroxide under neutral conditions using acridinium ester and its application to an enzyme immunoassay
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Hidetoshi Arakawa Keiko Tsuruoka Ken‐ichi Ohno Noriko Tajima Hiromi Nagano 《Luminescence》2014,29(4):374-377
We developed a highly sensitive chemiluminescent (CL) assay for hydrogen peroxide using 10‐methyl‐9‐(phenoxycarbonyl) acridinium fluorosulfonate (PMAC) that produced chemiluminescence under neutral conditions and applied it to an enzyme immunoassay (EIA). One picomole of hydrogen peroxide could be detected using the optimized PMAC‐CL method and 6.2 × 10‐20 mol β‐d ‐galactosidase (β‐gal) could be detected by combining an indoxyl derivative substrate and the proposed PMAC‐CL method. This highly sensitive CL β‐gal assay was applied to an EIA for thyroid‐stimulating hormone (TSH) using β‐gal as a label enzyme; 0.02–100.0 μU/mL TSH in human serum could be assayed directly and with high reproducibility. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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Shengyu Lv Hongrui Liu Jian Cui Tomoka Hasegawa Hiromi Hongo Wei Feng Juan Li Bao Sun Akira Kudo Norio Amizuka Minqi Li 《Journal of molecular histology》2014,45(3):303-309
The purpose of this study was to investigate immunolocalization of collagenolytic enzymes including cathepsin K, matrix metalloproteinase (MMP) 1 and 2 in the compressed periodontal ligament (PDL) during orthodontic tooth movement using a periostin deficient (Pn-/-) mouse model. Twelve-week-old male mice homozygous for the disrupted periostin gene and their wild type (WT) littermates were used in these experiments. The tooth movement was performed according to Waldo’s method, in which elastic bands of 0.5 mm thickness were inserted between the first and second upper molars of mice under anesthesia. At 1 and 3 days after orthodontic force application, mice were fixed with transcardial perfusion of 4 % paraformaldehyde in 0.1 M phosphate buffer (pH 7.4), and the first molars and peripheral alveolar bones were extracted for histochemical analyses. Compared with WT mice, immunolocalization of cathepsin K, MMP1 and MMP2 was significantly decreased at 1 and 3 days after orthodontic tooth movement in the compressed PDL of Pn-/- mice, although MMP1-reactivity and MMP2-reactivity decreased at different amounts. Very little cathepsin K-immunoreactivity was observed in the assessed regions of Pn-/- mice, both before and after orthodontic force application. Furthermore, Pn-/- mice showed a much wider residual PDL than WT mice. Taken together, we concluded that periostin plays an essential role in the function of collagenolytic enzymes like cathepsin K, MMP1 and MMP2 in the compressed PDL after orthodontic force application. 相似文献
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Hajime Sakaguchi Hiromi Hagiwara Yoshihiro Fukumori Yutaka Tamaura Minoru Funaki Shigehisa Hirose 《FEMS microbiology letters》1993,107(2-3):169-173
Abstract The magnetic bacterium Magnetospirillum magnetotacticum prefers a microaerobic habitat and should be able to sense oxygen. Therefore, the bacterium was cultured under atmospheres containing 0–5% O2 and analyzed for oxygen-dependent changes in the levels of its protein components by sodium dodecyl sulfate-polyccrylamide gel electrophoresis (SDS-PAGE). The analysis revealed a marked anaerobic induction of a 140-kDa protein, which was suppressed when M. magnetotacticum was switched from microaerobic (<1% O2 ) to aerobic (>1% O2 ) growth conditions. Although its function remains to be determined, the 140-kDa protein may serve as a useful tool to gain insight into the physiology of the organism. 相似文献
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The zinc(II) complex of pyridine-2-azo-p-dimethylaniline is bound to several acid proteinases, at pH 5.0, accompanied by a change is the visible absorption spectrum. Streptomyces pepsin inhibitor, which was discovered by Satoi and Murao (Satoi, S. and Murao, S. (1970) Agric. Biol. Chem. 34, 1265-1267 and Satoi, S. and Murao, S. (1971) Agric. Biol. Chem. 35, 1482-1487), is also bound to acid proteinases. Spectrophotometric studies with ten acid proteinases from different sources have revealed that in several acid proteinases, zinc(II)-pyridine-2-azo-p-dimethylaniline is released from the enzyme by the inhibitor, while some acid proteinase forms a quaternary complex, zinc(II)-pyridine-2-azo-p-dimethylaniline-inhibitor-enzyme. It is speculated that zinc(II)-pyridine-2-azo-p-dimethylaniline is bound to two catalytic carboxylate groups in the active site of the acid proteinases and the inhibitor is bound mainly to the substrate-binding site of the enzymes. The binding of the inhibitor may overlap the catalytic site completely or partially. The degree of overlapping is characteristic of the kind of acid proteinases. 相似文献