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101.
Reynaud CA Descatoire M Dogan I Huetz F Weller S Weill JC 《Cellular and molecular life sciences : CMLS》2012,69(10):1625-1634
Humoral memory is maintained by two types of persistent cells, memory B cells and plasma cells, which have different phenotypes
and functions. Long-lived plasma cells can survive for a lifespan within a complex niche in the bone marrow and provide continuous
protective serum antibody levels. Memory B cells reside in secondary lymphoid organs, where they can be rapidly mobilized
upon a new antigenic encounter. Surface IgG has long been taken as a surrogate marker for memory in the mouse. Recently, however,
we have brought evidence for a long-lived IgM memory B cell population in the mouse, while we have also argued that, in humans,
these same cells are not classical memory B cells but marginal zone (MZ) B cells which, as opposed to their mouse MZ counterpart,
recirculate and carry a mutated B cell receptor. In this review, we will discuss these apparently paradoxical results. 相似文献
102.
Sun L Rommens JM Corvol H Li W Li X Chiang TA Lin F Dorfman R Busson PF Parekh RV Zelenika D Blackman SM Corey M Doshi VK Henderson L Naughton KM O'Neal WK Pace RG Stonebraker JR Wood SD Wright FA Zielenski J Clement A Drumm ML Boëlle PY Cutting GR Knowles MR Durie PR Strug LJ 《Nature genetics》2012,44(5):562-569
Variants associated with meconium ileus in cystic fibrosis were identified in 3,763 affected individuals by genome-wide association study (GWAS). Five SNPs at two loci near SLC6A14 at Xq23-24 (minimum P = 1.28 × 10(-12) at rs3788766) and SLC26A9 at 1q32.1 (minimum P = 9.88 × 10(-9) at rs4077468) accounted for ~5% of phenotypic variability and were replicated in an independent sample of affected individuals (n = 2,372; P = 0.001 and 0.0001, respectively). By incorporating the knowledge that disease-causing mutations in CFTR alter electrolyte and fluid flux across surface epithelium into a hypothesis-driven GWAS (GWAS-HD), we identified associations with the same SNPs in SLC6A14 and SLC26A9 and established evidence for the involvement of SNPs in a third solute carrier gene, SLC9A3. In addition, GWAS-HD provided evidence of association between meconium ileus and multiple genes encoding constituents of the apical plasma membrane where CFTR resides (P = 0.0002; testing of 155 apical membrane genes jointly and in replication, P = 0.022). These findings suggest that modulating activities of apical membrane constituents could complement current therapeutic paradigms for cystic fibrosis. 相似文献
103.
Fernando A. Luz Gislene L. Gonçalves Vitor O. Becker 《Journal of Natural History》2015,49(31-32):1849-1875
The male, female, pupa and larva of a new species of Gelechiidae (Lepidoptera), Locharcha opportuna Moreira and Becker, are described and illustrated with the aid of optical and scanning electron microscopy. A preliminary analysis of mitochondrial DNA sequences including members of related lineages is also provided. The immature stages are associated with galls induced by a species of Palaeomystella Fletcher (Lepidoptera: Momphidae) on Tibouchina sellowiana (Cham.) Cogn. (Melastomataceae), endemic to the Atlantic Rainforest. Larvae are kleptoparasitic, usurping the gall internal space and thereafter feeding on the internal tissues. By determining the variation in population density of both species and following gall development individually throughout ontogeny under field conditions, we demonstrated that the kleptoparasite completes its life cycle inside galls induced by Palaeomystella, where pupation occurs. The variation in seasonal abundance of the kleptoparasite is tied to that of the cecidogenous species, with their corresponding peaks in density occurring sequentially.http://zoobank.org/urn:lsid:zoobank.org:pub:525F6D52-8CE1-47D1-A0D9-78B564DF5565 相似文献
104.
105.
G. Mathé P. Pouillart Françoise Lapeyraque 《Cellular and molecular life sciences : CMLS》1971,27(4):446-447
Résumé L'immunothérapie active non spécifique ou mixte, appliquée 24 h après la greffe isogénique de la leucémie RC 19, possède une action considérable; appliquée dans les mêmes conditions après la greffe de la leucémie E K1, elle possède une action modérée mais significative. Ces résultats confirment l'effet antileucémique de l'immunothérapie active appliquée après le début de la maladie et montre qu'elle est même efficace sur les cellules tumorales disséminées.
This work has been carried out with the aid of INSERM, contract No. 66-235. 相似文献
This work has been carried out with the aid of INSERM, contract No. 66-235. 相似文献
106.
107.
Maria Luiza Beçak Sylvia Mendes Carneiro K. Fukuda 《Cellular and molecular life sciences : CMLS》1978,34(2):171-173
Summary We describe the production of circles in chromomeric loops during the pachytene stage of the spermatocytes. These circles are found attached to chromatin or already free in the nucleoplasm. Each circle measures an average of 3700 Å in circunference. We suggest that such circles might indicate the presence of tandem repetitions.This work was supported by grants from Brazilian National Research Council-CNPq, Fundaçaó de Amparo à Pesquisa do Estado de S. Paulo-FAPESP and Instituto Butantan Research Found-FEDIB.We are grateful to Dr A. Brunner, Jr, for the permission to use the electron microscope. 相似文献
108.
A. S. Etienne J. Vauclair E. Emmanuelli M. Lançon J. Stryjenski 《Cellular and molecular life sciences : CMLS》1982,38(5):553-555
Summary Golden hamsters placed on a jumping stand from which they can descend onto a shallow or deep landing platform prefer to descend
on to the shallow platform, even when tested under IR-light without tactile cues. This preference disappears for subjects
with plugged ears. The simultaneous recording of the animal's behaviour and possible emission of ultrasound as well as experiments
in which the external acoustical conditions or the sound-reflecting properties of the jumping apparatus were altered suggest
that the animals use certain parameters of the ambient sound field for depth perception.
Acknowledgments. This research was supported by the Fonds National Suisse de la Recherche Scientifique, grant No. 3.349.74. 相似文献
109.
J. Diézi Françoise Roch-Ramel Françoise Chométy Pierrette Michoud G. Peters 《Cellular and molecular life sciences : CMLS》1969,25(9):932-933
Summary The renal tubular fate of urea, as studied in the rat by free-flow micropunctures of cortical tubules, is shown to vary with different types of diuresis (urea overloading, iso- or hypertonic saline diuresis). Under certain experimental conditions, the renal tubular handling of urea appears to differ in the cortical and the juxtamedullary nephrons.
Ce travail bénéficie du soutien du Fond National suiss de la Recharche Scientifique (crédit Nos. 4495 et 4983). 相似文献
Ce travail bénéficie du soutien du Fond National suiss de la Recharche Scientifique (crédit Nos. 4495 et 4983). 相似文献
110.
An updatable holographic three-dimensional display 总被引:2,自引:0,他引:2
Tay S Blanche PA Voorakaranam R Tunç AV Lin W Rokutanda S Gu T Flores D Wang P Li G St Hilaire P Thomas J Norwood RA Yamamoto M Peyghambarian N 《Nature》2008,451(7179):694-698
Holographic three-dimensional (3D) displays provide realistic images without the need for special eyewear, making them valuable tools for applications that require situational awareness, such as medical, industrial and military imaging. Currently commercially available holographic 3D displays use photopolymers that lack image-updating capability, resulting in restricted use and high cost. Photorefractive polymers are dynamic holographic recording materials that allow updating of images and have a wide range of applications, including optical correlation, imaging through scattering media and optical communication. To be suitable for 3D displays, photorefractive polymers need to have nearly 100% diffraction efficiency, fast writing time, hours of image persistence, rapid erasure, and large area-a combination of properties that has not been shown before. Here, we report an updatable holographic 3D display based on photorefractive polymers with such properties, capable of recording and displaying new images every few minutes. This is the largest photorefractive 3D display to date (4 x 4 inches in size); it can be recorded within a few minutes, viewed for several hours without the need for refreshing, and can be completely erased and updated with new images when desired. 相似文献