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921.
Jérôme Moreau Xavier Arruego Betty Benrey & Denis Thiéry 《Entomologia Experimentalis et Applicata》2006,119(2):93-99
The European grapevine moth, Lobesia botrana (Denis & Schiffermüller) (Lepidoptera: Tortricidae), is a major grapevine pest in Europe. The larva is polyphagous and able to develop on more than 25 plant species, several of them being more suitable than Vitaceae for the fitness of L. botrana. Larvae normally eat the pulp of the berry, but may also consume the seeds according to the development stage of the berry and the larval density per bunch. Understanding the effect on individual fitness of such feeding behaviour is important to assess how suitable the different berry tissues are for this insect. We offered to the larvae either entire berries, seeds, or pulp with skin of the variety Vitis vinifera cv. ‘Cabernet Sauvignon’ as larval food in order to assess several life history traits from egg hatching to adult death. Two control groups were raised on semisynthetic diets, offering a low (no plant material) or a higher (with corn flour) nutritive value medium. The larvae performed differently when fed on diets containing different parts of berries. The larvae fed on a diet containing grape berry seeds had a prolonged development time and showed higher mortality. The females emerging from these larvae had a lower fecundity and mating success than the females emerging from larvae fed on diets containing other parts of the berries. However, their longevity was greater in comparison to the other groups. We conclude that seeds of Cabernet Sauvignon are not toxic to larvae but affect the reproductive life history traits in L. botrana. 相似文献
922.
Jean‐Denis Pdelacq Beom‐Seop Rho Chang‐Yub Kim Geoffrey S. Waldo Timothy P. Lekin Brent W. Segelke Bernhard Rupp Li‐Wei Hung Su‐Il Kim Thomas C. Terwilliger 《Proteins》2006,62(3):563-569
The three‐dimensional structure of Rv2607, a putative pyridoxine 5′‐phosphate oxidase (PNPOx) from Mycobacterium tuberculosis, has been determined by X‐ray crystallography to 2.5 Å resolution. Rv2607 has a core domain similar to known PNPOx structures with a flavin mononucleotide (FMN) cofactor. Electron density for two FMN at the dimer interface is weak despite the bright yellow color of the protein solution and crystal. The shape and size of the putative binding pocket is markedly different from that of members of the PNPOx family, which may indicate some significant changes in the FMN binding mode of this protein relative to members of the family. Proteins 2006. © 2005 Wiley‐Liss, Inc. 相似文献
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Transgenic Mice Expressing Human Immunodeficiency Virus Type 1 in Immune Cells Develop a Severe AIDS-Like Disease 总被引:8,自引:4,他引:4 下载免费PDF全文
Zaher Hanna Denis G. Kay Marc Cool Serge Jothy Najet Rebai Paul Jolicoeur 《Journal of virology》1998,72(1):121-132
We have constructed transgenic (Tg) mice expressing the entire human immunodeficiency virus type 1 (HIV-1) coding sequences in cells targeted by HIV-1 infection in humans. These Tg mice developed a severe AIDS-like disease leading to early death (<1 month). They developed muscle wasting, severe atrophy and fibrosis of lymphoid organs, tubulointerstitial nephritis, and lymphoid interstitial pneumonitis. In addition the expression of RANTES was increased in various tissues of these Tg mice relative to that in the normal controls. Disease appearance was correlated with the levels of transgene expression. The numerous pathologies observed in these mice are remarkably similar to those observed in human AIDS and, more specifically, in pediatric AIDS. 相似文献
926.
Emmanuelle Petitfrere Herve Sartelet Denis Vivien Isabel Varela-Nieto Hassan Elbtaouri Laurent Martiny Bernard Haye 《Biochimie》1998,80(12):1063-1067
In porcine thyrocytes, TSH alone does not induce cell growth. Recently, it has been demonstrated that acute stimulation by TSH of porcine thyrocytes leads to release an inositolphosphate glycan (IPG) described as a putative second messenger for various growth factors in different cell types. IPG isolated from porcine thyrocytes induces proliferation of fibroblasts EGFR T17 and porcine thyrocytes. In porcine thyrocytes we have confirmed that cell growth requires the presence of both TSH and insulin. This effect is reproduced by 8-bromo cyclic AMP suggesting a mediation by intracellular cyclic AMP. Cooperative effects between 8-bromo cyclic AMP and IPG have also been evidenced and are in favour of a crosstalk between distinct signalling pathways. 相似文献
927.
F. Prieur T. Busso J. Castells R. Bonnefoy H. Benoit A. Geyssant C. Denis 《European journal of applied physiology and occupational physiology》1998,78(6):549-554
We have developed a gas exchange simulation system (GESS) to assess the quality control in measurements of metabolic gas
exchange. The GESS simulates human breathing from rest to maximal exercise. It approximates breath-by-breath waveforms, ventilatory
output, gas concentrations, temperature and humidity during inspiration and expiration. A programmable motion control driving
two syringes allows the ventilation to be set at any tidal volume (V
T), respiratory frequency (f), flow waveform and period of inspiration and expiration. The GESS was tested at various combinations of V
T (0.5–2.5 l) and f (10–60 stroke · min−1) and at various fractional concentrations of expired oxygen (0.1294–0.1795); and carbon dioxide (0.0210–0.0690) for a pre-set
flow waveform and for expired gases at the same temperature and humidity as room air. Expired gases were collected in a polyethylene
bag for measurement of volume and gas concentrations. Accuracy was assessed by calculating the absolute and relative errors
on parameters (error = measured−predicted). The overall error in the gas exchange values averaged less than 2% for oxygen
uptake and carbon dioxide output, which is within the accuracy of the Douglas bag method.
Accepted: 4 June 1998 相似文献
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Long-term remissions observed in four out of eight unselected patients with Burkitt''s lymphoma following seemingly non-specific treatment with Septicemine, are described. This is regarded as strong evidence of an effective immunological response. 相似文献