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421.
The roles of preconditioning and coiling upon entrance into anhydrobiosis by Aphelenchus avenae were tested via video-assisted analysis at 252°C. Fourth-stage juveniles or young adults of A. avenae were individually placed on 5% agar containing 0.8 M sucrose. Nematodes became quiescent within 3 hr, then gradually resumed a low level of activity and assumed a coiled posture. High desiccation survival rate was recorded when nematodes were incubated on agar for more than 6 hr; the survival rates were 0%, 3%, 73%, and 92% for 0, 2, 6, and 12 hr on agar, respectively. All nematodes placed on agar for 24 hr or more revived after rehydration following desiccation. Once nematodes were on agar for a sufficient time, no difference in desiccation survival was observed between nematodes taking a coiled posture and those uncoiled artificially. Based on these results, exposure to osmotic stress for 6 hr can prepare A. aveae physiologically for anhydrobiosis, but coiling does not appear to be a physiological requirement for desiccation in survival. 相似文献
422.
K Yamaguchi K Abe K Otsubo C Haniuda M Suzuki A Shimada S Kimura I Adachi T Kameya N Yanaihara 《Peptides》1984,5(2):415-421
During the period between 1967 and 1983, there were 28 WDHA patients in Japan. Clinically, these patients were not very different from those reported in western countries, but we have been able to add a few observations as follows. First, the WDHA patients with pancreatic endocrine tumors and those with neuroblastic tumors were present in almost equal numbers. Second, fluctuating hypercalcemia was often observed in patients with this syndrome, but it was not observed in any watery diarrhea due to the other etiologies. Third, the WDHA patients who have multiple endocrine neoplasia (MEN) type 1 have multiple tumors in the pancreas, indicating that the patients with MEN should be managed in a different manner in regard to determining tumor location as well as applying surgical treatment. When various types of tumors were examined for VIP content, it was found that many tumors have the potential to produce VIP, and when VIP is produced in large amounts, plasma VIP levels become elevated, resulting in the WDHA syndrome. 相似文献
423.
Summary The demography of shoots of eight populations of a herbaceous perennial exhibiting clonal growth, is presented. The study was done along an elevational gradient, from a more open secondary mixed forest to a denser, more mature stand. Most shoots lived one to three years on the average, but shoots as old as twelve years were found. Large variation in formation and mortality of shoots was observed among plots and years. Yearly trends in the mortality rates of site replicates showed a higher correlation than rates of shoot formation. Although the density of shoots was highest in the drier sites, the turnover of shoots was highly variable and apparently uncorrelated with site location. Age structures revealed a tendency of longer-lived and higher reproductive activities among shoots from more mesic sites. It is hypothesized that environmental rather than density controls are primary causes of the population dynamics observed in this species. 相似文献
424.
Improving the quality of agro-wastes by solid-state fermentation: enhanced antioxidant activities and nutritional qualities 总被引:1,自引:0,他引:1
A. Lateef J. K. Oloke E. B. Gueguim Kana S. O. Oyeniyi O. R. Onifade A. O. Oyeleye O. C. Oladosu A. O. Oyelami 《World journal of microbiology & biotechnology》2008,24(10):2369-2374
Solid substrate fermentations of some agro-wastes, namely cocoa pod husk (CPH), cassava peel (CP), and palm kernel cake (PKC)
were carried out for the production of fructosyltransferase (FTase) by a newly isolated fungal strain Rhizopus stolonifer LAU 07. The fermented substrate were studied for improved nutritional quality by determining the crude protein, crude fibre,
ash and lipid contents, and antioxidant activities. The cyanide content of cassava peels was also determined. Some levels
of value-addition occured as a result of the fermentation. The protein contents of the substrates increased by 33.3, 55.4,
and 94.8%, while the crude fibre contents decreased by 44.5, 8.6, and 7.2% in PKC, CP, and CPH, respectively. The cyanide
content of cassava peel was reduced by 90.6%. Generally, fermentation of the substrates by R. stolonifer LAU 07 increased the antioxidant activity in a DPPH (1,1-diphenyl-2-picrylhydrazyl) assay. The IC50 (mg/ml) values of the methanolic extracts (fermented/unfermented) were obtained as 7.0/14.9, 4.4/10.6, and 5.5/14.7 mg/ml
for PKC, CP, and CPH, respectively. Results herein reported showed that the nutritional qualities and antioxidant activities
of all the investigated solid substrates were enhanced by fungal fermentation. Thus, scope exists for microbial upgrading
of these low-quality agro-wastes and development of healthy animal feed supplements. 相似文献
425.
Participation of Hydrogen Peroxide in the Inactivation of Calvin-Cycle SH Enzymes in SO2-Fumigated Spinach Leaves 总被引:1,自引:0,他引:1
In SO2-fumigated spinach leaves under light, chloroplast SHenzymes, glyceraldehyde-3-phosphate dehydrogenase (NADP-GAPD)(EC 1.2.1.13
[EC]
), ribulose-5-phosphate kinase (Ru5PK) (EC 2.7.1.19
[EC]
)and fructose-1,6-bisphosphatase (FBPase) (EC 3.1.3.11
[EC]
) weremore remarkably inactivated than other chloroplast enzymes.Their activities recovered after removal of SO2. The inactivationparalleled light-dependent CO2-fixation in spinach leaves. Inilluminated chloroplasts isolated from SO2-fumigated spinachleaves, NADP-GAPD and Ru5PK were more specifically in activatedthan other chloroplast enzymes. These two enzymes could be protectedfrom the inactivation by adding catalase. The NADP-GAPD inactivationwas suppressed by DCMU, cytochrome c or anaerobic conditions.By adding thiol compounds, the NADP-GAPD inactivation was dischargedand the activity increased. In chloroplasts or crude extractsfrom non-fumigated spinach leaves, NADP-GAPD and Ru5PK weremore strongly inhibited by externally added H2O2 than otherchloroplast enzymes. All results supported the idea that thesuppression of photosynthesis at the beginning of SO2 fumigationwas caused by the reversible inhibition of chloroplast SH enzymewith H2O2. (Received October 7, 1981; Accepted June 16, 1982) 相似文献
426.
Hiromi Mutsuura Kenji Kanbara Mikihiko Fukunaga Kazumi Yamamoto Ikumi Ban Kana Kitamura Yoshihide Nakai 《Applied psychophysiology and biofeedback》2009,34(4):291-298
Patients presenting with functional somatic syndrome (FSS) are common, and the symptoms are persistent and difficult to treat
for doctors and costly for society. The aim of this study was to clarify the common pathophysiology of FSS, especially the
relationship between hypothalamic-pituitary-adrenal (HPA) axis function and psychological characteristics of patients with
FSS. The subjects were 45 patients with FSS and 29 healthy controls. Salivary free cortisol was measured in the morning, and
psychological tests examining depression, anxiety and quality of life (QOL) were performed on the same day. In patients with
FSS, depressive scores showed a significant negative correlation with salivary free cortisol in the morning, although in healthy
controls, cortisol showed a significant positive correlation with depressive scores. In addition, the correlation between
other psychological test scores and cortisol secretion in patients with FSS contrasted with that of controls. The relationship
between cortisol and depression, anxiety or QOL, suggests that the HPA axis of patients with FSS is dysfunctional and does
not function properly when patients with FSS are under stress. This dysfunction may explain the pathology of medically unexplained
persistent symptoms of patients with FSS. 相似文献
427.