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The relationship was evaluated between early nutritional experiences, the intestinal microflora and the small intestinal functions in the mechanism of predisposition to obesity development. Male Sprague-Dawley rats were used in which the quantity of nutrition was manipulated from birth to weaning (day 30) by adjusting the number of pups in the nest to 4 small litters (SL) and 10 normal litters (NL) and fed a standard diet from days 30 to 40 of age. After 40 d, the postnatally overfed SL pups became heavier, displayed significantly enhanced adiposity, body mass gain and food intake as well as a significantly higher jejunal alkaline phosphatase and maltase activity than in rats nursed in NL nests. The effect of different early nutrition was also accompanied by the appearance of significantly decreased Bacteroides and significantly increased enterococci and lactobacilli of obese rats than in lean NL rats. The amounts of Bacteroides were negatively correlated with fat pad mass, body mass, body-mass gain and food intake whereas enterococci and lactobacilli were correlated positively with the same parameters. Our results demonstrate that postnatal nutritional experience may represent a predisposing factor influencing ontogeny of small intestine function and development of intestinal microbial communities. The acquired changes and associated alterations in food digestion could be a component of regulatory mechanisms contributing to the development of obesity and its maintenance in later life. 相似文献
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The influence of increasing concentrations (0.1, 1.0 and 5.0 mg l−1) of fluoranthene (FLT) on growth, endogenous abscisic acid (ABA) level and primary photosynthetic processes in 21-day-old
pea plants (Pisum sativum L.) in vitro was investigated. Murashige and Skoog’s (MS) medium, with or without FLT, was enriched with indole-3-acetic
acid (IAA; 0.1 mg l−1) or a combination of IAA (0.1 mg l−1) plus N6-benzyladenine (BA; 0.1 mg l−1). The level of endogenous ABA significantly increased with increasing FLT concentrations in the presence of both IAA and
IAA plus BA. An increased level of endogenous ABA was observed in plants treated with IAA alone. The growth of shoot, callus
and the content of photosynthetic pigments (chlorophyll a and b, carotenoids), in both IAA- and IAA plus BA-treated plants, were significantly stimulated by FLT at its lowest concentration
(0.1 mg l−1) assayed in this study. However, FLT at higher concentrations (1.0 and 5.0 mg l−1) significantly inhibited all these parameters. Chlorophyll fluorescence imaging showed that FLT only at the highest concentration
(5.0 mg l−1) in the presence of IAA (0.1 mg l−1) significantly increased F0, but decreased FV/FM and ΦII. 相似文献
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Effects of zinc (12–180 μM) alone and in mixtures with 12 μM Cd on metal accumulation, dry masses of roots and shoots, root
respiration rate, variable to maximum fluorescence ratio (FV/FM), and content of photosynthetic pigments were studied in hydroponically cultivated chamomile (Matricaria recutita) plants. The content of Zn in roots and shoots increased with the increasing external Zn concentration and its accumulation
in the roots was higher than that in the shoots. While at lower Zn concentrations (12 and 60 μM) the presence of 12 μM Cd
decreased Zn accumulation in the roots, treatment with 120 and 180 μM Zn together with 12 μM Cd caused enhancement of Zn content
in the root. Presence of Zn (12–120 μM) decreased Cd accumulation in roots. On the other hand, Cd content in the shoots of
plants treated with Zn + Cd exceeded that in the plants treated only with 12 μM Cd. Only higher Zn concentrations (120 and
180 μM) and Zn + Cd mixtures negatively influenced dry mass, chlorophyll (Chl) and carotenoid content, FV/FM and root respiration rate. Chl b was reduced to a higher extent than Chl a. 相似文献
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Nezbedová S Bezoušková S Kofroňová O Benada O Rehulka P Rehulková H Goldová J Janeček J Weiser J 《Folia microbiologica》2011,56(6):519-525
The glass beads cultivation system developed in our laboratory for physiological studies of filamentous microorganisms supports
differentiation and allows complete recovery of bacterial colonies and their natural products from cultivation plates. Here,
we used this system to study the global effect of ppk gene disruption in Streptomyces lividans. The ppk encoding the enzyme polyphosphate kinase (P) catalyses the reversible polymerisation of gamma phosphate of ATP to polyphosphates.
The resulting are phosphate and energy stock polymers. Because P activity impacts the overall energetic state of the cell,
it is also connected to secondary metabolite (e.g. antibiotic) biosynthesis. We analysed the global effects of the disruption
of this gene including its influence on the production of pigmented antibiotics, on morphological differentiation, on the
levels of ATP and on the whole cytoplasmic protein expression pattern of S. lividans. We observed that the S. lividans ppk mutant produced antibiotics earlier and in greater amount than the wild-type (wt) strain. On the other hand, we did not observe any obvious effect on colony morphological development. In agreement with
the function of Ppk, we detected much lower levels of ATP in ppk- mutant than in the wt strain. Proteomic analysis revealed that the genes that were influenced by ppk inactivation included enzymes involved in carbon or nitrogen metabolism, phosphate transport and components of the cell translational
machinery. We showed that the synthesis of translation elongation factor Tu is during sporulation much higher in ppk- mutant than in wild-type strain. 相似文献
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Marie Kummerová Lucie Váňová Helena Fišerová Marek Klemš Štěpán Zezulka Jana Krulová 《Plant Growth Regulation》2010,61(2):161-174
Environmental contaminants like polycyclic aromatic hydrocarbons can influence many biochemical and physiological processes
in plants. The effect of 0.1, 1 and 5 mg l−1 of fluoranthene (FLT) in combination with indole-3-acetic acid (IAA, 0.1 mg l−1) or a combination of IAA and N6-benzyladenine (BA, both 0.1 mg l−1) on the growth and production of ethylene, ethane and CO2 in Pisum sativum L. cultivated for 21 days in vitro was investigated. In 21 days old plants also net photosynthesis rate, content of FLT and
cytokinins were evaluated. FLT 5 mg l−1 significantly inhibited the growth of pea after 21 days in both IAA and IAA + BA treatments, increased production of ethylene
(by 11% in IAA and 14% in IAA + BA treatments, respectively) and ethane (by 28 and 18%) and decreased production of CO2 (by 23 and 29%). The net photosynthesis rate decreased in response to FLT concentration by up to 51% under saturating irradiation
(600–1,200 μmol m−2 s−1), as found in IAA + BA + FLT 5 mg l−1 treatment. The content of FLT in pea plant shoots well correlated with increasing FLT treatment in both IAA and IAA + BA
medium. The content of cytokinins in pea shoots changed in response to FLT treatment. FLT 5 mg l−1 caused a rise in level of trans-zeatin (by 16% in IAA and 9% in IAA + BA treatments, respectively), dihydrozeatin riboside (by 27 and 50%), benzyladenine
(by 3 and 80%), benzyladenine riboside (by 44 and 17%) and meta-topolin riboside (by 139 and 214%), no change in isopentenyladenine level and a decrease in meta-topolin level (by 33% in IAA and 36% in IAA + BA treatments, respectively). Cultivation of plants in vitro allowed not only
to assess their growth, photosynthetic activity and the level of cytokinins, but also to extend the knowledge about the effect
of PAHs on production of gaseous stress indicators like ethylene, ethane and CO2. Recorded changes in all studied parameters show, that persistent organic pollutants like PAHs can negatively influence plant
growth and development. 相似文献
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The resistance of goose (Anser anser f. domestica) eggs to damage was determined by measuring the average rupture force, specific deformation and rupture energy during their compression at different compression speeds (0.0167, 0.167, 0.334, 1.67, 6.68 and 13.36 mm/s). Eggs have been loaded between their poles (along X axis) and in the equator plane (Z axis). The greatest amount of force required to break the eggs was required when eggs were loaded along the X axis and the least compression force was required along the Z axis. This effect of the loading orientation can be described in terms of the eggshell contour curvature. The rate sensitivity of the eggshell rupture force is higher than that observed for the Japanese quail’s eggs. 相似文献
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Marie Kummerová Štěpán Zezulka Lucie Váňová Helena Fišerová 《Central European Journal of Biology》2012,7(1):159-166
This study confirmed the considerable effect of polycyclic aromatic hydrocarbon fluoranthene (FLT; 0.01, 0.1, 1, 4 and 7 mg/l)
exposure on the germination of seeds, growth and root morphology of seedlings in Zea mays and Pisum sativum. Seed germination was significantly inhibited at FLT≥0.01 mg/l in maize and at ≥1 mg/l in pea. The amount of released ethylene
after 3 days of germination was significantly increased in both species at FLT≥0.1 mg/l. After 7 days of seedling cultivation
a significant decrease in the dry weight of roots and shoots occurred in maize at FLT≥0.1 mg/l while in pea similar effect
was observed at ≥1 mg/l. The total length of primary and lateral roots was significantly reduced by FLT≥1 mg/l in maize and
by 4 and 7 mg/l in pea. The length of the non-branched part of the primary root was significantly reduced by FLT≥0.1 mg/l
in maize and ≥0.01 mg/l in pea. In both species the number of lateral roots was significantly increased at FLT≤1 mg/l and
inhibited at concentrations of 4 and 7 mg/l. Fluoranthene content in roots and shoots of both species positively correlated
with the FLT treatment. 相似文献
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