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991.
Streptomyces fradiae IFO 3439 elaborated enzymes with macerating activity toward various plant tissues. The optimum pH of the macerating activity was about 8.0 when the crude enzyme preparation acted on disks of potato tuber or pieces of Ganpi (Wikstroemia sikokiana Fr. et Sav.) bark. Pectolytic activities in this preparation toward free pectin or poly-galacturonic acid were considerably lower than those of fungi or bacteria. However, when the crude enzyme preparation acted on native pectin in Ganpi bark, about 90 per cent of the galacturonic acid residues were recovered as the polygalacturonides having a still high degree of polymerization. These results suggested that the crude enzyme of S. fradiae solubilized Ganpi pectin, degrading it to only a very small extent. 相似文献
992.
To find why water hyacinth accumulates the toxic heavy metalion Cd2+, the plant was cultivated in a mineral medium supplementedwith Cd2+. Cd accumulated in the roots against the concentrationgradient, mostly as a soluble form in the cytoplasm. Chromatographywith Sephadex G-25 and G-50 columns showed that the accumulatedCd was present in two forms with mol wt of 2,300 and 3,000.The components carrying Cd showed a high ratio of absorbanceat 254 nm to that at 280 nm, which suggests that they resemblemammalian Cd-thioneins. These components were not detected inthe roots of water hyacinth cultivated in the absence of Cd2+,indicating that they are formed in response to the Cd2+ supplement. (Received September 6, 1984; Accepted November 30, 1984) 相似文献
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996.
Masayuki Hanaoka Yunden Droma Atsuhiko Naramoto Takayuki Honda Toshio Kobayashi Keishi Kubo 《Journal of applied physiology》2003,94(5):1836-1840
To examine the role of VEGF in the pathogenesis of high-altitude pulmonary edema (HAPE), we measured the concentrations of VEGF in venous serum and bronchoalveolar lavage fluid in patients with HAPE and in healthy volunteers. The VEGF in venous serum of the patients was normal at admission and significantly increased at recovery. Similarly, the VEGF in bronchoalveolar lavage fluid of the patients was increased at recovery compared with admission, but values at both admission and recovery were significantly lower than those of the controls. The present finding suggests that VEGF probably is destroyed in the lung of HAPE, and it appears less likely to have a critical part in the pathogenesis of HAPE but has rather an important role in the repair process for the impaired cell layer. 相似文献
997.
Masayuki Adachi Ryoichi Saito Yoshikuni Tanioka 《Primates; journal of primatology》1982,23(4):583-586
Seven deliveries of rhesus monkeys maintained in the laboratory were recorded by a video recorder system to determine the
signs of impending labor. The characteristic postures; i.e., standing, squatting and crouching, were demonstrated in all cases
with cyclic regularity (about 2–4 min) 35–210 min prior to the actual parturition, although prediction of the delivery date
several days beforehand failed. The four stages of the delivery process are also presented in this report. 相似文献
998.
A high level of free-abscisic acid (ABA) was detected when corms were still in deep dormancy. The level of free-ABA decreased as the corm dormancy disappeared and increased temporarily after complete release from dormancy. A gradual slight increase of bound-ABA was observed during dormancy release.Treatment of dormant corms with benzyladenine (BA) increased sprouting but the sprouts did not show normal growth. Ethylene treatment induced complete sprouting and subsequent normal growth. Changes in ABA levels and ethylene production are discussed in relation to dormancy release in freesia corms. 相似文献
999.
Hideki Kimura Kazuko Kamiyama Toru Imamoto Izumi Takeda Shinya Masunaga Mamiko Kobayashi Daisuke Mikami Naoki Takahashi Kenji Kasuno Takeshi Sugaya Masayuki Iwano 《Biochemistry and Biophysics Reports》2022
The main lesion of cisplatin nephrotoxicity is damage to proximal tubular cells due to increased apoptosis via the mitochondrial and death receptor pathways, which may be alleviated by appropriate promotion of autophagy. Fenofibrate, a peroxisome proliferator-activated receptor-alpha (PPAR-α) activator, is recently reported to promote autophagy as well as protect against cisplatin nephrotoxicity, although the mechanisms were only partially analyzed. Here, the detailed mechanisms of these putative protective effects were investigated in a murine renal proximal tubular (mProx) cell line. Fenofibrate attenuated cisplatin-induced apoptosis of mProx cells based on flow cytometry. As for the mitochondrial apoptotic pathway, the reagent reduced cisplatin-stimulated caspase-3 activation by decreasing the phosphorylation of p53, JNK, and 14-3-3, cytosolic and mitochondrial Puma accumulation, cytochrome C release to the cytosol, and resulting cytosolic caspase-9 activation. Fenofibrate also decreased cisplatin-stimulated activation of caspases-8 by suppressing MAPK and NFkB pathways and reducing the gene expression of TNF-α, TL1A, and Fas, main mediators of the death receptor apoptotic pathway. Autophagy defined by p62 reduction and an increase in LC3 II/I was promoted by fenofibrate in mProx cells under starvation. Autophagy inhibition using 3-MA further increased basal and cisplatin-induced caspase-3 and -8 activation, but had no influence on the inhibitory effects of fenofibrate on caspase activation. In conclusion, our study suggests fenofibrate to be a candidate agent to mitigate cisplatin nephrotoxicity by inhibiting the mitochondrial and death apoptotic pathways rather than by promoting autophagy. 相似文献
1000.
He Hai Iizuka Takahiro Maekawa Maho Sadahisa Kumi Morikawa Toshinobu Yanase Masanori Yokoi Shuji Oda Masayuki Tezuka Takahiro 《Journal of plant research》2019,132(4):461-471
Journal of Plant Research - Reproductive isolation, including prezygotic and postzygotic barriers, is a mechanism that separates species. Many species in the Nicotiana section Suaveolentes exhibit... 相似文献