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91.
Changes in the development of uterine pinopodes in steroid hormone supplemented cycles 总被引:9,自引:0,他引:9
Oborná I Novotný R Brezinová J Petrová P Lichnovský V Fingerová H 《Physiological research / Academia Scientiarum Bohemoslovaca》2004,53(4):423-429
The endometrium acquires the ability to implant a hatched blastocyst only within a specific time termed the receptive phase. Ovarian steroid hormones are essential for structural and functional changes that prepare the endometrium to be receptive. Pinopodes have been suggested to be markers of uterine receptivity. The aim of this study was to compare the pinopode expression and serum levels of ovarian steroid hormones in the mid-luteal phase of the natural cycle and in a "mock" cycle in the same subject. Sequentional endometrial biopsies within 48 hours were obtained from women in the mid-luteal phase (ovulation +5, ovulation +7) of the natural cycle and in the "mock" cycle (progesterone supplementation +5 and +7). Biopsies were examined under a scanning electron microscope for pinopode detection. The expression of pinopodes was similar in both cycles, where pinopodes covered about 5 % of the endometrial surface. The developmental stages were also similar with a slight increase of fully developed pinopodes in both samples in the "mock" cycles. Our findings suggest that hormonal preparation of the endometrium do not change the timing of pinopode expression. 相似文献
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94.
Parmee ER He J Mastracchio A Edmondson SD Colwell L Eiermann G Feeney WP Habulihaz B He H Kilburn R Leiting B Lyons K Marsilio F Patel RA Petrov A Di Salvo J Wu JK Thornberry NA Weber AE 《Bioorganic & medicinal chemistry letters》2004,14(1):43-46
Substituted 4-amino cyclohexylglycine analogues were evaluated for DP-IV inhibitory properties. Bis-sulfonamide 15e was an extremely potent 2.6 nM inhibitor of the enzyme with excellent selectivity over all counterscreens. 2,4-difluorobenzenesulfonamide 15b and 1-naphthyl amide 16b, however, combined an acceptable in vitro profile with good pharmacokinetic properties in the rat, and 15b was orally efficacious at 3 mpk in an OGTT in lean mice. 相似文献
95.
A central goal in genome biology is to understand the origin and maintenance of genic diversity. Over evolutionary time, each gene's contribution to the genic content of an organism depends not only on its probability of long-term survival, but also on its propensity to generate duplicates that are themselves capable of long-term survival. In this study we investigate which types of genes are likely to generate functional and persistent duplicates. We demonstrate that genes that have generated duplicates in the C. elegans and S. cerevisiae genomes were 25%–50% more constrained prior to duplication than the genes that failed to leave duplicates. We further show that conserved genes have been consistently prolific in generating duplicates for hundreds of millions of years in these two species. These findings reveal one way in which gene duplication shapes the content of eukaryotic genomes. Our finding that the set of duplicate genes is biased has important implications for genome-scale studies. 相似文献
96.
Semeniuk EG Stremovskiĭ OA Orlova IV Baladin TG Nosov AM Bur'ianov IaI Deev SM Petrov RV 《Molekuliarnaia biologiia》2003,37(5):916-923
A recombinant scFv antibody against human spleen ferritin was expressed as a barstar-fused protein in Escherichia coli and in Nicotiana tabacum plants and suspension cell cultures. As demonstrated by immunoblotting with antibarstar antibodies, direction of the recombinant protein to the endomembrane system of plant cells ensured its stability and solubility. Production of the recombinant protein did not differ between parental transgenic plants and their first-generation progeny. Fusion with barstar allowed not only immunochemical detection of the recombinant scFv antibody, but also their purification from the plant material by affinity chromatography with barnase-His6 immobilized on a metal-affinity carrier. 相似文献
97.
Comparative analysis of diffusive and stress induced nutrient transport efficiency in the lacunar-canalicular system of osteons 总被引:3,自引:0,他引:3
Marker migration experiments suggest that cyclic mechanical loading of cortical bone in vivo increases marker penetration into bone. Is this a result of stress induced fluid flow or of stress stimulation of active transport processes? Active lacunar-canalicular transport of nutrients was suggested by Ham in 1979 on the basis of the presence of actin filaments in osteocyte processes and their suspected role in cell motility. In addition, Tanaka in 1984 observed active transport of microperoxidase in bone and Tanaka-Kamioka et al. in 1998 observed experimentally that osteocyte processes are able to actively change their form. In this study we performed parametric and comparative analyses of the transport efficiencies of diffusion and stress generated fluid flow of (glucose) nutrients in lacunar-canalicular systems in cortical bone. The result obtained is that neither diffusion nor stress induced fluid flow is capable of sustaining osteocyte viability. It is possible that cyclic stress stimulates an active nutrient transport mechanism to supplement stress flows. 相似文献
98.
Atypical puffing of polytene chromosomes of Chironomus plumosus (1 larvae, IV stage) from the Ivan lake in Chita region, southern part of Siberia, has been described. At the sites of ordinary localization of interdisks and puff-patterns typical of Ch. plumosus the puffs in our material displayed different levels of activity: from a light vacuolous spot to puffs of class 5. Most of these puffs were revealed in Ch. plumosus for the first time, namely, puffs IA10a-r, IB12v-y + 13a-d, IIC14p-z + 15a-z + 16a-e, IIC14p-z + 15a-h, IID14a-m + 13s-w, IID11-2a-d, IID1p-x + 2a-d, IIIE3g-a and IIIF13h-p + 14a-e. Some other puffs, such as IB16a-k, IB15m-r + 16a-m, IB21a-o, IIC20, IVG6 and IVG7, were described earlier (Maksimova, 1979, 1983). The majority of observed puffs turned out to be heterozygous. Only one puff-knob, IIIE3g-a of class 5 activity, was found in all cells of the studied salivary glands. Its origin may be due to the appearance of heterozygoous inversion pluE1.2. All other puffs were observed in some part of cells. It is supposed that the appearance of larvae with unusually high functional activity of chromosomes may be presumably induced by stress influence of certain environmental factors. 相似文献
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100.
The spatial and temporal patterns of post-embryonal cell growth and cell division were characterised in excised cotyledons
of vegetable marrow (Cucurbita pepo L. var. giromontia Alef.) incubated in water. The concurrent roles of these two processes in cotyledon growth were determined using paradermal
sections of the first palisade layer of developing cotyledons. Tissue specificity was observed in the pattern of cell division.
The daughter cells derived from an initial cell, which had already differentiated before imbibition of the seeds, were tightly
packed in a cluster, which enabled us to monitor cell division during early cotyledon development. Heterogeneity of cell size
was recognised during the process of cell proliferation in the cluster, suggesting that cell division is uncoupled from control
of cell size. There was significantly more cell division in the marginal part of the cotyledons than in other parts, suggesting
high activity of the marginal meristem. Light enhanced cell and cotyledon enlargement, but had no effect on the number of
divisions. This study elucidated the cellular basis of post-germinative Cucurbita cotyledon morphogenesis and development.
Electronic Publication 相似文献