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91.
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Adhesion tests are complex, time‐consuming and expensive, while the most important criterion for a probiotic lactobacilli is the ability to adhere to the human intestine. Thirty lactobacilli isolates from human intestinal tissues were measured for cell surface glyceraldehyde‐3‐phosphate dehydrogenase (GAPDH) activity using a microtiter plate screening method. GAPDH activities were detected in 21 out of 30 samples from 12 h cultures and in all samples from 18 h cultures. This suggests GAPDH is universally expressed on the bacterial cell surfaces from many lactobacilli. A statistically significant positive correlation was shown between GAPDH activity and adhesion using the BIACORE adhesion assay (P < 0.01). The new screening method using GAPDH enzymatic activity without an adhesion test may be possible due to the significant positive correlation of GAPDH activity with adhesion of lactobacilli derived from the human intestine.  相似文献   
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Infanticide was first observed in langurs nearly 50 years ago, and this rare phenomenon has been inferred to have either an evolutionarily adaptive function or to be a pathological and non‐functional behavior. In this study, we report 5 male takeover events in one‐male groups of white‐headed langurs in the Nongguan Karst Hills, Guangxi, China from 1998 to 2006. We recorded 13 attacks on 9 infants by extra‐group males or new resident males. During the male takeovers, all of the infants younger than 6 months (with an average age of 3.6 months [N = 11]) in the groups disappeared. The infant death rate during the 4.2 months after takeover by a new male was significantly higher than the infant death rate calculated for most of the year. Older infants that were still nursing (with an average age of 14.1 months [N = 7]) were often attacked and seriously wounded by the extra‐group males or new resident males, but all of them survived. The interbirth intervals of females whose infants were assumed to be killed by males were significantly reduced relative to those of females in groups with stable male tenure (mean = 10 months vs 25 months). Our data suggest that males kill unrelated and unweaned infants during the takeover period to decrease the time until the infants’ mothers resume fertility. Thus, infanticide would support sexual selection theory in white‐headed langurs. The data also show that infanticidal behavior was directed toward the infants, especially those who were still nursing. Female dispersal may function as a counter‐strategy to avoid infanticide.  相似文献   
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This study was conducted to determine the reproductive characteristics of Barbarea vulgaris under different disturbance regimes (mowing and tilling) in two different habitats: a levee and a wheat field. On the levee, 77 of the 114 individuals that had had their floral stalks removed by the first mowing produced new rosettes at the basal part of the stem during the same growing season. The plants that were mowed four times per year had a significantly greater survival rate than the plants that were mowed twice per year. The levee population that was mowed without tillage was largely maintained by vegetative reproduction. These results suggest that mowing the levees promotes the vegetative reproduction of B. vulgaris and helps it to compete with tall-growing plants, thus facilitating its survival as a perennial. In spite of the high sprouting ability of the plant's root fragments, most of the root fragments did not regenerate when buried or when exposed to high soil moisture conditions in tilled wheat fields. The population of B. vulgaris in tilled wheat fields was maintained almost entirely by sexual reproduction. Barbarea vulgaris can survive under two different management regimes by altering its mode of reproduction.  相似文献   
96.
选用蛋白水平(CP)为7%及14%的大米蛋白(R-7,R-14)及酪蛋白(C-7,C-14)喂养20周龄雄性Wistar大鼠2周后,进行大鼠体质量变化、腹腔贮脂水平、血浆总胆固醇、血浆高密度胆固醇、血浆甘油三酯及肝脏胆固醇、甘油三酯含量的测定。与C-7组相比,R-7组大鼠体质量、生长效率、贮藏脂肪含量、血脂及肝脂水平无显著差异。在高蛋白水平(14%)下,R-14组大鼠体质量总增加量、腹腔贮脂水平均低于C-14组,但各组间无显著差异;对比C-14,R-14显著降低了成熟期大鼠血浆总胆固醇、血浆非高密度胆固醇、血浆甘油三酯水平及动脉硬化指数,并且显著降低了肝脏胆固醇及甘油三酯含量。结果表明,蛋白水平是大米蛋白调控体质量及体脂水平主要影响因素之一。随着蛋白水平的增加(7%~14%),大米蛋白能够降低体质量增加量及腹腔贮脂水平,并显著降低成熟期大鼠血浆及肝脏脂质含量,提示大米蛋白潜在的抗肥胖功能与其蛋白水平密切相关。  相似文献   
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The effects of leaches from dry leaves of 71 ground cover plant species on lettuce were tested at the first screening. The inhibitory effects on radicle and hypocotyl elongations of lettuce varied with the different species of cover plants that were used. Eight species of Oxalis showed strong inhibitions (4–27% of untreated control on radicle elongation). Inhibitory activities of seven species of cover plants on three weed species, live amaranth ( Amaranthus lividus ), southern crabgrass ( Digitaria ciliaris ) and common lambsquarters ( Chenopodium album ), were tested at the second screening. Moss pink ( Phlox subulata ), trefoil ( Oxalis brasiliensis ), red spiderlily ( Lycoris radiata ), creeping thyme ( Thymus serpyllum ), European pennyroyal ( Mentha pulegium ), roman chamomile ( Chamaemelum nobile ) and star-of-Bethlehem ( Ornithogalum umbellatum ) were selected as donor plants because of their high inhibitory effects on lettuce growth and their usefulness as ornamental ground cover plants. Effects of leaches from dry leaves and exudates from the roots of these species were assayed on agar. Radicle elongations of all tested weed species were inhibited by leaches from trefoil and red spiderlily (8–31% and 14–24% of untreated control, respectively) and exudates from moss pink, trefoil and creeping thyme (11–43%, 31–74% and 22–67% of untreated control, respectively).  相似文献   
100.
1-Phenyl-5(4 H )-4-dialkylcarbamoyltetrazolinones represent a new class of herbicides that are active against barnyardgrass ( Echinochloa spp.) in paddy fields. To select the most favorable compound as a paddy herbicide, herbicidal activity and selectivity of the carbamoyltetrazolinone compounds to transplanted rice were determined in greenhouse tests. Higher herbicidal activities were associated with the compounds having a 2-Cl- or 2-Cl-6-Me-substituted or an unsubstituted phenyl ring, and a combination of C2–3 linear alkyl group and a C4 branched-chain alkyl or a C5–6 cycloalkyl group on the nitrogen atom in the carbamoyl structure. In addition, the compounds carrying a total of seven to nine carbon atoms in the substituents on the carbamoyl nitrogen exhibited a good selectivity between barnyardgrass and transplanted rice plants. From the results of soil thick-layer chromatography, the good crop compatibility of carbamoyltetrazolinones was correlated to the mobility of the compounds in paddy soil. The investigation resulted in the selection of an excellent compound, 4-(2-chlorophenyl)- N -cyclohexyl- N -ethyl-4,5-dihydro-5-oxo-1 H -tetrazole-1-carboxamide (common name: fentrazamide), as a rice paddy herbicide for controlling barnyardgrass.  相似文献   
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