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51.
52.
Claude Bouchard Angelo Tremblay Jean-Pierre Desprs Germain Thriault Andr Nadeauf Paul J. Lupien Sital Moorjani Denis Prudhomme Guy Fournier 《Obesity (Silver Spring, Md.)》1994,2(5):400-410
Seven pairs of young adult male identical twins completed a negative energy balance protocol during which they exercised on cycle ergometers twice a day, 9 out of 10 days, over a period of 93 days while being kept on a constant daily energy and nutrient intake. The total energy deficit caused by exercise above the estimated energy cost of body weight maintenance reached 244 ± 9.8 MJ (Mean ± SEM). Baseline energy intake was estimated over a period of 17 days preceding the negative energy balance protocol. Mean body weight loss was 5.0 kg (SEM = 0.6) (p <0.001) and it was entirely accounted for by the loss of fat mass (p <0.001). Fat-free mass was unchanged. Body energy losses reached 191 MJ (SEM = 24) (p <0.001) which represented about 78% of the estimated energy deficit. Subcutaneous fat loss was slightly more pronounced on the trunk than on the limbs as estimated from skinfolds, circumferences, and computed tomography (CT). The reduction in CT-assessed abdominal visceral fat was quite striking, from 81 cm2 (SEM = 5) to 52 cm2 (SEM = 6) (p <0.001). At the same submaximal power output level, subjects oxidized more lipids than carbohydrates after the program as indicated by the changes in the respiratory exchange ratio (p <0.05). Intrapair resemblance was observed for the changes in body weight (p <0.05), fat mass (P <0.01), percent fat (p <0.01), body energy content (p <0.01), sum of 10 skinfolds (p <0.01), abdominal visceral fat (p <0.01), fasting plasma triglycerides (p <0.05) and cholesterol (p <0.05), maximal oxygen uptake (p <0.05), and respiratory exchange ratio during submaximal work (p <0.01). We conclude that even though there were large individual differences in response to the negative energy balance and exercise protocol, subjects with the same genotype were more alike in responses than subjects with different genotypes particularly for body fat, body energy, and abdominal visceral fat changes. High lipid oxidizers and low lipid oxidizers during sub-maximal exercise were also seen despite the fact that all subjects had experienced the same exercise and nutritional conditions for about three months. 相似文献
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Species of Borrelia distinguished by restriction site polymorphisms in 16S rRNA genes 总被引:2,自引:0,他引:2
David Ralph Daniele Postic Guy Baranton Charles Pretzman Michael McClelland 《FEMS microbiology letters》1993,111(2-3):239-243
Abstract Three phyletic groups of Borrelia associated with Lyme disease, B. burgdorferi, B. garinii and group VS461 can be distinguished from each other and other species of Borrelia by Bfa I restriction site polymorphisms in PCR amplified 16S rRNA genes. One strain isolated from an Ixodes pacificus tick in California that was previously unclassifiable was distinguishable from B. burgdorferi by an Mnl I restriction site polymorphism. 相似文献
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Colonies of the African stink ant Paltothyreus tarsatuslocated in the forest have nests with shorter horizontal galleries and a smaller total foraging surface than colonies located in open areas. Each solitary worker specializes on the same central or peripheral hunting zone but she does not specialize on a particular sector during group-retrieving. The search for prey is characterized by a wandering walk with spatial parameters varying in two ways. Capture of a termite releases a path characterized by sinuosity and a decrease in speed of movement. In contrast, a failure in the course of an attempted capture releases an increase in both sinuosity and speed of movement corresponding to a socalled reserve behavior. Each worker shortens her retrieving trip in comparison with her search trip and the straightness of the homing paths depends on the size and shape of the prey. Our data show that behavioral flexibility at the individual level in P. tarsatusis important in determining spatial foraging strategy at the colony level. 相似文献
57.
Le Maître Anne Guy Franck Merceron Gildas Kostopoulos Dimitris S. 《International journal of primatology》2023,44(1):209-236
International Journal of Primatology - Discoveries in recent decades indicate that the large papionin monkeys Paradolipopithecus and Procynocephalus are key members of the Late Pliocene –... 相似文献
58.
Brice Maxime Nkouayeb Nangmou Hermine Laure Maza Djomkam Georges Bellier Tabekoueng Willifred Dongmo Tékapi Tsopgni Gabin Thierry Mbahbou Bitchagno Michel Arnaud Mbock Raceline Gounoue Kamkumo Marcel Frese Bruno Ndjakou Lenta Silvère Augustin Ngouela Nobert Sewald Anatole Guy Blaise Azebaze 《化学与生物多样性》2023,20(4):e202200271
The root extract of Nauclea xanthoxylon (A.Chev.) Aubrév. displayed significant 50 % inhibition concentration (IC50s) of 0.57 and 1.26 μg/mL against chloroquine resistant and sensitive Plasmodium falciparum (Pf) Dd2 and 3D7 strains, respectively. Bio-guided fractionation led to an ethyl acetate fraction with IC50s of 2.68 and 1.85 μg/mL and subsequently, to the new quinovic acid saponin named xanthoxyloside ( 1 ) with IC50s of 0.33 and 1.30 μM, respectively against the tested strains. Further compounds obtained from ethyl acetate and hexane fractions were the known clethric acid ( 2 ), ursolic acid ( 3 ), quafrinoic acid ( 4 ), quinovic acid ( 5 ), quinovic acid 3-O-β-D-fucopyranoside ( 6 ), oleanolic acid ( 7 ), oleanolic acid 3-acetate ( 8 ), friedelin ( 9 ), β-sitosterol ( 10a ), stigmasterol ( 10b ) and stigmasterol 3-O-β-D-glucopyranoside ( 11 ). Their structures were characterised with the aid of comprehensive spectroscopic methods (1 and 2D NMR, Mass). Bio-assays were performed using nucleic acid gel stain (SYBR green I)-based fluorescence assay with chloroquine as reference. Extracts and compounds exhibited good selectivity indices (SIs) of >10. Significant antiplasmodial activities measured for the crude extract, the ethyl acetate fraction and xanthoxyloside ( 1 ) from that fraction can justify the use of the root of N. xanthoxylon in ethnomedicine to treat malaria. 相似文献
59.
The territorial African weaver ant Oecophylla longinoda forages in a 3-dimensional system when attending honeydew secreted by coccid colonies. The orienting strategy allowing workers to reach a static food resource was studied in laboratory conditions. Contrary to other studies devoted to territoriality in O. longinoda, our experiments show that, when moving off the nest, territorial faecal marking by the major workers is not randomly placed all over the home-range area. The chemical trail leading from the nest to a given food site is reinforced by faecal materials both on the horizontal and the vertical planes. In addition to visual cues and chemical trails laid by the major workers (Holldobler & Wilson 1978), foragers use the territorial marking both to localize the food site and to come back to the nest. Thus, anal-drop deposition in O. longinoda also has a clear dual-purpose function: territorial and orientationai marking. The ecological value of such a discrete Tom Thumb's orienting strategy enables workers to quickly reach a food location even after more than 5 months of inactivity on this given site. The persistent marked trail also has an intercolonial effect. This could allow the keeping of exploitation of a definite food site by alien colonies of the same species by reducing time costs for new exploring phases or for learning new spatial cues when foraging on an unknown environment. 相似文献
60.
Guy Levavassur Gerald E. Edwards C. Barry Osmond Joseph Ramus 《Journal of phycology》1991,27(6):667-672
A computerized oxygen electrode Astern was used to make rapid and accurate measurements of photosynthetic light and dissolved inorganic carbon (DIC) response cures with a macroalga. Ulva rotundata Blid. was grown in an outdoor, continuous flow system in seawater under sunlight or 9% of sunlight at Beaufort, North Carolina. The light compensation points in the shade- and sun-grown plants, measured in seawater, were at photon flux densities (PFDs) of 16 and 27 μmol. Photons·m?2·s?1, respectively but the quantum yield of O2 evolution was not significantly different. Rates of photosynthesis in seawater per unit area of thallus under saturating light and rates of dark respiration were about 1.5-fold higher in sun- than in shade-grown plants. The concentration of DIC in seawater (approximately 2 mM) limited photosynthesis at absorbed PFDs above 60–70 μmol photons·m?2·s?1 Addition of 20 mM inorganic carbon had no effect on quantum yield but caused about a 1.5-fold increase in the light-saturated photosynthetic rate in both shade- and sun-grown Ulva. The effect of DIC supplementation was greatest in plants grown in October and least in plants grown in June. The light- and DIC-saturated rate of photosynthesis in seawater was similar to the maximum rate obtained by exposing Ulva to 10% CO2, in the gas phase. The carbon isotope values (δ13C, reflecting the 13C/12C ratio compared to a standard) of Ulva grown in the same seawater supply were dependent on light and agitation. Samples from Beaufort Inlet were more negative (δ13C value, ?20.03‰) than those grown in bright light with agitation (δ13C value, ?17.78‰ outdoors; ?17.23‰ indoors), which may indicate DIC supply limited carbon uptake in seawater. 相似文献