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91.
In addition to the 16 previously reported polyphenols including 3 new ellagitannins, 2 novel dicarboxylic acid derivatives, glansreginins A (1) and B (2), and a new dimeric hydrolyzable tannin, glansrin D (3), were isolated, together with 15 known compounds from walnuts, the seeds of Juglans regia. The structures of the new compounds were elucidated on the basis of 1D- and 2D-NMR analyses and chemical data. The antioxidant effect of these isolates was also evaluated by SOD-like and DPPH radical scavenging activities.  相似文献   
92.
93.
Acute hypotonic stress becomes a threat to the survival of bacteria in the environment. Mechanosensitive channels play an essential role in the maintenance of bacterial cell integrity during hypoosmotic shock. A database search suggested that Campylobacter jejuni, a major worldwide cause of bacterial gastroenteritis in humans, possesses two putative mechanosensitive channels, designated Cjj0263 and Cjj1025, in C. jejuni strain 81-176. Osmotic downshock experiments demonstrated that a mutant lacking Cjj0263 showed a severe defect in survival of hypoosmotic shock, while a mutant lacking Cjj1025 exhibited the same survival capacity as the wild type. We further examined the colonization ability of each mutant using the one-day old chick model. Cjj0263 or Cjj1025 mutants were able to colonize chick ceca at the same level as the wild type, but a Cjj0263 Cjj1025 double mutant revealed significantly reduced ability to colonize chick ceca. To examine whether C. jejuni that have grown in the digestive tract of chicks are protected against acute hypotonic stress, bacteria in ceca were directly exposed to water. The wild type was able to survive acute osmotic downshift, but the Cjj0263 mutant suffered a substantial loss of viability when subjected to a rapid osmotic downshock. Immunoblot analysis suggested that both Cjj0263 and Cjj1025 were glycosylated via the N-linked protein glycosylation pathway, but glycan modification of these proteins was unlikely to have a major effect on their function and stability. Our data suggest that Cjj0263, a mechanosensitive channel, has a pivotal role in protection against hypoosmotic stress experienced during environmental transmission.  相似文献   
94.
Terminal molting probability (TMP) of snow crab Chionoecetes opilio was estimated using instar- and state-structured model incorporating the terminal molt in the waters off the Pacific coast of northern Honshu, Japan. TMP is defined as the probability that terminal molt occurs within a year in an instar and is an important parameter for stock assessment. TMP was estimated from the model and the rate of terminal molted crabs (RTM) for instars, which means carapace widths over 30 mm. Carapace widths at RTM of 0.5 were 81 mm for males and 66 mm for females. TMP was estimated as 0.23 and 0.29 for these carapace widths, respectively. Carapace widths at TMP of 0.5 were 94 mm for males and 71 mm for females, and for these carapace widths 57% of male and 50% of female crabs were considered as old-shell which had survived 1 year or more from terminal molt. Changing the fishing or natural mortality by ±0.1, the maximum difference of TMP was less than 0.1 from default estimates.  相似文献   
95.
Vermicomposting differs from conventional composting because the organic material is processed by the digestive systems of worms. The egested casts can be used to improve the fertility and physical characteristics of soil and potting media. In this study, the effects of earthworm casts (EW), conventional compost (CP) and NPK inorganic fertilizer (FT) amendments on N mineralization rates, microbial respiration, and microbial biomass were investigated in a laboratory incubation study. A bioassay with wheat (Triticum aestivium L.) was also conducted to assess the amendment effects on plant growth and nutrient uptake and to validate the nutrient release results from the incubation study. Both microbial respiration and biomass were significantly greater in the CP treatment compared to EW treatment for the initial 35 days of incubation followed by similar respiration rates and biomass to the end of the study at 70 days of incubation. Soil NO3 increased rapidly in the EW and CP treatments in the initial 30 days of incubation, attaining 290 and 400 mg N kg−1 soil, respectively. Nitrate in the EW treatment then declined to 120 mg N kg−1 soil by day 70, while nitrate in the CP treatment remained high. While ammonium levels decreased in the CP treatment as nitrate level increased with increasing incubation time, a low level of ammonium was maintained in the EW treatment throughout the incubation. The wheat bioassay study included two additional cast treatments (EW-N and EW2) to have treatments with higher levels of N input. Plants grown with CP or FT treatment had a lower shoot biomass and higher shoot N content than in EW-N and EW-2 treatments, and also showed symptoms of salinity stress. Ionic strength and other salinity indicators in the earthworm cast treatments were much lower than in the CP treatment, indicating a lower risk of salinity stress in casts than in compost. All cast and compost amendments significantly increased wheat P and K uptake compared to either the non-amended control or the mineral fertilizer treatment. The results show that casts are an efficient source of plant nutrients and that they are less likely to produce salinity stress in container as compared to compost and synthetic fertilizers.  相似文献   
96.
Tsutomu Yabuya 《Euphytica》1991,52(3):215-219
Summary Following bud pollination of tartary buckwheat (Fagopyrum tataricum) with pollens from common buckwheat (F. esculentum), cv. Mancan, 31% of the ovaries began to grow but all turned brown and withered after 6 to 14 days. Fluorescence microscopy of the growing ovaries showed the pollen-tube entering the embryo-sac. The ovules from the growing ovaries failed to produce any embryo in the culture medium in which the immature embryos from the self-pollinated (compatible) tartary flowers were able to mature and germinate. No embryo development was observed after cross-pollination. The interspecific incompatibility is attributed to the failure of gametes to fuse.Abbreviations BAP benzylaminopurine - IAA indoleacetic acid  相似文献   
97.
98.
A dog with purulent vulval discharge was found to have many cysts containing purulent mucus in the uterine cervix. The uterine horns did not contain any pus. Histological examination revealed a cervical adenomyosis infiltrated by many neutrophils. After an ovariohysterectomy including the whole cervix, the dog recovered well.  相似文献   
99.
Twenty growing crossbred cattle and crossbred water buffalo (carabao) with an average age of 22 (18–24 months) months were equally distributed into two treatment groups according to species. The animals were fed with the same ration made up of corn silage (50%) + wet brewer's spent grain (30%) + concentrate mixture (20%), and their fattening performance was monitored. The digestibilities of the different nutrients were likewise determined. The economics of raising the animals under intensive production system was calculated. Species differences did not influence total dry matter intake of the animals, when expressed as percentage of the bodyweight and per metabolic body size. There were no significant differences in digestion coefficients of the different nutrients, except for crude protein in crossbred water buffalo and crossbred cattle, although the digestibility of dry matter, organic matter and nitrogen free extract tended to be high in the former than in the latter. Likewise, average daily gain (ADG) was similar, although crossbred water buffalo had numerically higher ADG (828.6 vs 785.5 g) than crossbred cattle during the 6 months feeding. During the first 3 months of feeding (1–90 days), the ADG of crossbred water buffalo was 1066.1 g compared to 940.1 g for crossbred cattle. From 91 to 180 days, the crossbred cattle had slightly higher ADG (630.1 vs 591.1 g) but also the difference was not significant. The return above feed cost was comparable for crossbred cattle and crossbred water buffalo during the first 90 days of feeding. However, extending the feeding period from 91 to 180 days , income over feed cost was higher (P < 0.05) for crossbred cattle by PhP 5.3/kg gain than crossbred water buffalo. Results showed that crossbred water buffalo could attain similar growth rate with that of crossbred cattle under intensive system, when fed with high quality feed materials.  相似文献   
100.
The effect of dietary energy levels on the urinary excretion of purine derivatives (PD) was investigated in sheep fed hay and concentrate diets. In addition, the possibility of using PD concentrations in spot samples of urine as a useful tool for determining daily PD excretion was also examined. Three female lambs (mean bodyweight (BW) ± standard error, 31.4 ± 1.0 kg) were fed three diets consisting of timothy hay (20 g dry matter/kg BW per day) and rolled barley at three different energy levels (low‐energy (LE), medium‐energy (ME) and high‐energy (HE) at 1.0‐, 1.2‐ and 1.5‐fold greater than the maintenance level of energy (450 KJ/BW0.75/day), respectively) in a 3 × 3 Latin square design. The dietary protein level was almost constant (380 mg nitrogen/BW0.75/day as digestible crude protein base) and was adjusted using soybean protein. Digestible organic matter intake (DOMI) increased (P < 0.05) with an increase in the dietary energy level and there was a difference (P < 0.05) in the organic matter digestibility between the LE and HE diets. For urinary PD excretion, the differences between the LE and ME diets and the HE diet were significant (P < 0.05), although there was no clear difference between the LE and ME diets. There was a positive correlation (r = 0.47, P < 0.05) between urinary PD excretion and DOMI. There was also a correlation (r = 0.59, P < 0.05) between the urinary PD level at 7–8 h after the morning feed and the daily total PD excretion, suggesting that the PD level in spot urine samples could be useful for estimating microbial protein synthesized in the rumen and/or digested in the lower gut.  相似文献   
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