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281.
Riehle MM Guelbeogo WM Gneme A Eiglmeier K Holm I Bischoff E Garnier T Snyder GM Li X Markianos K Sagnon N Vernick KD 《Science (New York, N.Y.)》2011,331(6017):596-598
Population subgroups of the African malaria vector Anopheles gambiae have not been comprehensively characterized owing to the lack of unbiased sampling methods. In the arid savanna zone of West Africa, where potential oviposition sites are scarce, widespread collection from larval pools in the peridomestic human habitat yielded a comprehensive genetic survey of local A. gambiae population subgroups, independent of adult resting behavior and ecological preference. A previously unknown subgroup of exophilic A. gambiae is sympatric with the known endophilic A. gambiae in this region. The exophilic subgroup is abundant, lacks differentiation into M and S molecular forms, and is highly susceptible to infection with wild Plasmodium falciparum. These findings might have implications for the epidemiology of malaria transmission and control. 相似文献
282.
Mahdavi J Sondén B Hurtig M Olfat FO Forsberg L Roche N Angstrom J Larsson T Teneberg S Karlsson KA Altraja S Wadström T Kersulyte D Berg DE Dubois A Petersson C Magnusson KE Norberg T Lindh F Lundskog BB Arnqvist A Hammarström L Borén T 《Science (New York, N.Y.)》2002,297(5581):573-578
Helicobacter pylori adherence in the human gastric mucosa involves specific bacterial adhesins and cognate host receptors. Here, we identify sialyl-dimeric-Lewis x glycosphingolipid as a receptor for H. pylori and show that H. pylori infection induced formation of sialyl-Lewis x antigens in gastric epithelium in humans and in a Rhesus monkey. The corresponding sialic acid-binding adhesin (SabA) was isolated with the "retagging" method, and the underlying sabA gene (JHP662/HP0725) was identified. The ability of many H. pylori strains to adhere to sialylated glycoconjugates expressed during chronic inflammation might thus contribute to virulence and the extraordinary chronicity of H. pylori infection. 相似文献
283.
Bjørn O. Eggum Inge Hansen Torben Larsen 《Plant foods for human nutrition (Dordrecht, Netherlands)》1989,39(1):13-21
Chemical analyses and balance trials with rats of 17 foods showed marked differences in protein quality. According to anin vitro procedure true protein digestibility was high (around 90%). The same was also the case for thein vivo values with the exception of two legumes, beans and chick peas, which were digested to a markedly lower degree when compared to thein vitro values. The assumed reason for this is discussed. Due to extensive differences in the amino acid composition of the 17 samples BV varied considerably with the lowest value (45.5) of rice-wheat gluten breakfast cereal. Energy digestibility was generally high. Amino acid digestibility determinedin vivo followed the pattern of the corresponding protein digestibility, although marked differences occurred from one amino acid to another in the same food. 相似文献
284.
Tarnow I Olsen LH Kvart C Hoglund K Moesgaard SG Kamstrup TS Pedersen HD Häggström J 《Veterinary journal (London, England : 1997)》2009,180(2):195-201
Natriuretic peptides are useful in diagnosing heart failure in dogs. However, their usefulness in detecting early stages of myxomatous mitral valve disease (MMVD) has been debated. This study evaluated N-terminal (NT) fragment pro-atrial natriuretic peptide (NT-proANP) and NT-pro-brain natriuretic peptide (NT-proBNP) in 39 Cavalier King Charles Spaniels (CKCS) with pre-clinical mitral valve regurgitation (MR), sixteen dogs with clinical signs of heart failure (HF) and thirteen healthy control dogs. Twenty seven CKCS and ten control dogs were re-examined 4 years after the initial examination and the status of the dogs 5 years after the initial examination was determined by telephone calls to the owner. All dogs were evaluated by clinical examination and echocardiography. CKCS with severe MR had higher NT-proANP and NT-proBNP compared to controls and CKCS with less severe MR. Dogs with clinical signs of HF had markedly elevated NT-proANP and NT-proBNP. Plasma concentrations of the natriuretic peptides measured at re-examination could predict progression in regurgitant jet size. 相似文献
285.
OBJECTIVE: To characterise misreporters of energy intake (EI) and energy expenditure (EE). DESIGN: Cross-sectional study, using a validated position and motion instrument, ActiReg, as the reference method to study misreporters of EI and of EE. EI was measured using a dietary record and EE using a physical activity questionnaire (PAQ). Misreporters were defined as subjects outside the 95% confidence limits of agreement between EI or EE reported/EE measured. SETTING: Free-living Danish volunteers. SUBJECTS: One hundred and thirty-eight volunteers aged between 20 and 59 years. RESULTS: Body mass index, smoking, 'try to eat healthily' and worries about weight were related to degree of under-reported EI. The percentage energy from added sugar was lowest (P < 0.001) and the percentage energy from protein (P < 0.001) highest in under-reporters compared with acceptable reporters. Subjects who reported being very physically active at work or in leisure time reported a higher EE than measured EE compared with less physically active subjects (P < 0.05). Likewise, subjects who regard themselves as fit or very fit reported a higher EE than subjects who regard themselves as moderately fit (P < 0.05). Possible over-reporters reported less time as very light activity (P = 0.007), more time as moderate activity (P = 0.01) and more time as vigorous activity (P = 0.02) than acceptable reporters. CONCLUSIONS: Under-reporting of EI should always be taken into consideration; however, only a few characteristics of under-reporters are consistent among studies. Misreporting of EI was more prevalent than misreporting of EE. The level of physical activity more than the time spent involved in various activities was misreported. 相似文献
286.
Influence of lipid composition of live feed on growth,survival and pigmentation of turbot larvae 总被引:17,自引:0,他引:17
The effect of different lipid compositions of live feed on the survival, growth rate and pigmentation success of turbot larvae, Scophthalmus maximus (L.), was investigated. Rotifers, Brachionus plicatilis, together with the algae Tetraselmis sp., were administered until day 12, and Artemia was fed until day 27. The experimentally treated live feeds were enriched with four formulated emulsions, resulting in a gradient in the relative contents of 3 HUFA (highly unsaturated fatty acids) and in DHA (docosahexaenoic acid, 22:6 3)/EPA (eicosapentaenoic acid, 20:5 3) ratios in both the rotifers and Artemia.There were no differences in larval growth rate, and only small differences in survival rate throughout the feeding experiment, probably because of satisfactory levels of 3 HUFA in the live feed to sustain growth and survival. A correlation was obtained between the percentage of completely pigmented 27 d old turbot and the DHA/EPA ratio in the total lipids of 12 d old larvae, which again was correlated with the corresponding ratio in the live feed used. The results suggest that normal pigmentation in turbot requires dietary DHA in the early larval feeding period, and that this requirement cannot be replaced by EPA. 相似文献