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141.
142.
Yuji Shimizu Shimpei Sato Jun Koyamatsu Hirotomo Yamanashi Mako Nagayoshi Koichiro Kadota Mami Tamai Kazuhiko Arima Hironori Yamasaki Yosuke Kusano Noboru Takamura Takahiro Maeda 《Journal of physiological anthropology》2014,33(1):7
Background
Renal impairment is known to be associated with atherosclerosis, which in turn is reported to be positively associated with hemoglobin levels. In addition, renal impairment is known to be associated with a form of anemia known as renal anemia.Methods
To clarify the associations between renal impairment and anemia, we conducted a cross-sectional study of 1,105 60 to 89-year-old men, who were not taking medication for anemia and were undergoing general health check-ups.Results
Compared with non-chronic kidney disease, chronic kidney disease (CKD) with a glomerular filtration rate (GFR) <60 mL/min/1.73 m2 was found to constitute a significant risk of anemia. However, we noted that this risk was lower for mild renal impairment (60 mL/min/1.73 m2 ≤ GFR <90 mL/min/1.73 m2). Compared with the non-CKD reference group, the classical cardiovascular risk factors adjusted odds ratio (OR) for anemia was 1.81 (1.23 to 2.68) and compared with the normal renal function (GFR ≥90 mL/min/1.73 m2) reference group, the ORs for mild renal impairment and CKD were 0.26 (0.15 to 0.47) and 0.60 (0.33 to 1.09).Conclusions
Independent from classical cardiovascular risk factors, CKD, which was identified during general health check-ups, appeared to constitute a significant risk of anemia for older Japanese men. For mild renal impairment, however, this association was a reduced risk of anemia and thus possibly a higher risk of atherosclerosis. 相似文献143.
144.
β-Glucanases were found in the cell wall of Lilium longiflorum Thunb. pollen tubes grown in vitro . The activity of β-glucanases was, in a certain extent, decreased by nojirimycin, an inhibitor of glucosidase. Pollen germination percentage reduced dramatically when nojirimycin was applied in the culture medium. In case that nojirimycin was added at 0 or 1 h after the onset of incubation, the inhibition rate was 99.6% and 91.4%, respectively. When 3 mmol/L of nojirimycin was applied in the liquid medium at 0, 1, 1.5 and 2 h after the onset of incubation, the growth of pollen tubes was interrupted, which resulted in the morphological change of the pollen tubes such as the newly grown portion of pollen tubes being bent, curved and swollen. Tracing the growth pattern of the individual pollen tube grown in semi-solid medium by video microscopy, the authors demonstrated that pollen tube growth rate was strongly inhibited by nojirimycin at concentrations ranged from 0.003 to 3 mmol/L. Moreover, the cytoplasmic arrangement and the morphology of the pollen tubes were also affected by nojirimycin. The growth inhibition brought about by nojirimycin was reversible. These results indicated that β-glucanases, which degrade 1,3-β-glucan and/or 1,4-β-glucan or 1,3:1,4-β-glucan constructed in the cell wall, are involved in pollen germination and pollen tube growth. It provides new insight into an understanding of the contribution of β-glucanases to the cell wall extensibility and the crucial role of cell wall in regards to the regulation of pollen tube growth. 相似文献
145.
Linda C. McCarthy Marie-Therese Bihoreau Susanna L. Kiguwa Julie Browne Takeshi K. Watanabe Haretsugu Hishigaki Atsushi Tsuji Susanne Kiel Caleb Webber Maria E. Davis Catherine Knights Angela Smith Ricky Critcher Patrick Huxtall James R. Hudson Jr. Toshihide Ono Hiroumi Hayashi Toshihisa Takagi Yusuke Nakamura Akira Tanigami Peter N. Goodfellow G. Mark Lathrop Michael R. James 《Mammalian genome》2000,11(9):791-795
146.
147.
Inhibition of RANKL‐dependent cellular fusion in pre‐osteoclasts by amiloride and a NHE10‐specific monoclonal antibody
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148.
A raw starch utilizing microbe was isolated from mud in a milling factory. The 16S ribosomal DNA (rDNA) sequencing and morphological properties of the strain indicated that it belongs to the genus Streptomyces. A strongly raw starch digesting amylase was purified from the culture supernatant of the strain by chromatographic procedures. The specific activity of the enzyme was 11.7 U/mg, molecular mass 47 kDa, optimum pH 6.0, and optimum temperature 50 to 60 degrees C. The enzyme showed sufficient activity even at 70 degrees C. It was activated by calcium, cobaltous, and magnesium ions, and inhibited by copper, nickel, zinc, and ferrous ions. It formed maltose mainly from raw and gelatinized starch, and glycogen. No products were formed from glucose, maltose, maltotriose, pullulan, or cyclodextrins (CDs). The enzyme digested raw wheat, rice, and waxy rice starch rapidly, and raw corn, waxy corn, sweet potato, tapioca, and potato starch normally. 相似文献
149.
Detoxification of cadmium in tobacco plants: formation and active excretion of crystals containing cadmium and calcium through trichomes 总被引:18,自引:0,他引:18
In tobacco (Nicotiana tabacum L.), long and short trichomes can be distinguished morphologically. The established function of long trichomes is to exude
a sticky gum containing diterpenes, whereas that of short trichomes is not known. When tobacco seedlings were exposed to toxic
levels of cadmium (Cd), growth was retarded, but trichome number was increased up to 2-fold in comparison with untreated samples.
Observation by variable-pressure scanning electron microscopy (VP-SEM) indicated that large crystals of 150 μm in size were
formed on head cells of both short and long trichomes. An energy-dispersive X-ray analysis system fitted with VP-SEM revealed
the crystals to contain amounts of Cd and calcium (Ca) at much higher concentrations than in the head cells themselves. Transmission
electron microscopy demonstrated crystal formation in amorphous osmiophilic deposits in vacuoles. When seedlings were treated
with Cd in the presence of Ca, tolerance was increased in proportion to the increase in Ca concentration. These results indicate
that tobacco plants actively exclude toxic Cd by forming and excreting Cd/Ca-containing crystals through the head cells of
trichomes.
Received: 26 June 2000 / Accepted: 20 September 2000 相似文献
150.
Jun Udagawa Toshihisa Hatta Hiroyuki Naora Ryuju Hashimoto Masashi Tashiro Osamu Tanaka Hiroki Otani 《Biological Rhythm Research》2001,32(1):73-84
D2O increased hair length in Balb/c nu/nu (nude) mice in our previous study although it has an antimitotic effect in cells. To investigate the mechanism of the effect on the hair length, we examined the change by the administration of D2O in the duration of the hair cycle and the proliferating activity of the hair matrix in relation with hair length in nude mice. The results showed that 20 or 30% D2O administration did not change the gross structure of the hairs, the proliferative activity and keratinization of the hair matrix cells, but elongated the hair cycle. The duration of the hair cycle increased by the administration of D2O in a dose-dependent manner over the examined range and these effects were reversible by discontinuation of D2O. The change in the hair length correlated with the change in the hair-existing phase particularly. We also showed that the mast cell density in the skin, which is related to the hair cycle, increased in the deuterated mice at anagen VI stage which nearly corresponds to the hair-existing phase. The increase in the mast cell density may be related to the increase in the hair cycle duration. These findings indicate that the increase in hair length may be due to the increase in the duration of the hair cycle, in particular, an increase in the hair-existing phase. This study thus suggests that D2O slows not only short-term cycles such as circadian clock or ultradian clock, but also the hair cycle which is a long-term cycle. 相似文献