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991.
Simulation of ultrasound backscattering by red cell aggregates: effect of shear rate and anisotropy 下载免费PDF全文
Tissue characterization using ultrasound (US) scattering allows extraction of relevant cellular biophysical information noninvasively. Characterization of the level of red blood cell (RBC) aggregation is one of the proposed application. In the current paper, it is hypothesized that the microstructure of the RBCs is a main determinant of the US backscattered power. A simulation model was developed to study the effect of various RBC configurations on the backscattered power. It is an iterative dynamical model that considers the effect of the adhesive and repulsive forces between RBCs, and the effect of the flow. The method is shown to be efficient to model polydispersity in size, shape, and orientation of the aggregates due to the flow, and to relate these variations to the US backscattering properties. Three levels of aggregability at shear rates varying between 0.05 and 10 s(-1) were modeled at 40% hematocrit. The simulated backscattered power increased with a decrease in the shear rate or an increase in the RBC aggregability. Angular dependence of the backscattered power was observed. It is the first attempt to model the US power backscattered by RBC aggregates polydisperse in size and shape due to the shearing of the flow. 相似文献
992.
993.
Lessons of a day hospital: Comprehensive assessment of patients with albinism in a European setting 下载免费PDF全文
Aurélie Marti Eulalie Lasseaux Khaled Ezzedine Christine Léauté‐Labrèze Franck Boralevi Clément Paya Valentine Coste Vincent Deroissart Benoit Arveiler Alain Taieb Fanny Morice‐Picard 《Pigment cell & melanoma research》2018,31(2):318-329
Albinism is a rare genetic disease, comprising syndromic and non‐syndromic forms. We assessed clinical and genetic characteristics in a prospective evaluation of 64 patients (33 children and 31 adults) seen at a specialized day hospital. Causative genetic mutations were found in TYR (23/64, 35.9%), OCA2 (19/64, 29.7%), TYRP1 (1/64, 1.6%), SLC45A2 (12/64, 18.7%), C10orf11 (1/64, 1.6%), HPS1 (3/64, 4.7%), HPS5 (1/64, 1.5%), HPS6 (1/64, 1.6%) and GPR143 (2/64, 3.1%). Causative mutations remained undetermined for one patient (1.6%). Heterogeneity for hair and skin phenotype was noted across and within the different genotypes. Skin and hair hypopigmentation did not correlate with visual impairment. The diagnosis of unrecognized syndromic forms and of cases of ocular albinism in this prospective and comprehensive series of patients with albinism in a European setting is remarkable. Photoprotection was overall good but not optimal. 相似文献
994.
Eva Kaufmann Joaquin Sanz Jonathan L. Dunn Nargis Khan Laura E. Mendonça Alain Pacis Fanny Tzelepis Erwan Pernet Anne Dumaine Jean-Christophe Grenier Florence Mailhot-Léonard Eisha Ahmed Jad Belle Rickvinder Besla Bruce Mazer Irah L. King Anastasia Nijnik Clinton S. Robbins Maziar Divangahi 《Cell》2018,172(1-2):176-190.e19
995.
Eliezer A. Rachmilewitz Hanna Tamari Fanny Liff Yoshihiro Ueda R. L. Nagel 《Human genetics》1985,70(2):119-125
Summary We have studied 105 individuals in the village of Jasser El Zarka in the Northern Coast of Israel of whom 59% had at least one abnormal hemoglobin. Of the individuals studied 41% were AA, 13.3% AS, 28.6% AOArab, 10.5% SOArab, 0.9% SS, 38% Arab-+ Thal, and 1.9% Thal trait. The SOArab double heterozygotes were characterized by a normal mean corpuscular volume (MCV) and mean corpuscular hemoglobin concentration (MCHC), and an increase of Hb F (11.7±4.3%) and 2,3-diphosphoglycerate levels (27.8 m/g Hb). The increase of Hb F is higher than the one seen among OArabs of other ethnic backgrounds. Their clinical course was moderately severe and osteoporosis was quite frequent. The interactions of Hb OArab and Hb S were studied in vitro and it was confirmed the Hb OArab lowers the minimal gelling concentration of mixtures with Hb S (as compared to mixtures of Hb S and Hb A), but that this effect is ionic-strength dependent. Our data are in conflict with previous claims that Hb OArab mixtures with Hb S polymerized almost as much as pure S. Oxygen association curves show a significant displacement of the p50 to the right, but the effect of oxygen dissociation is less apparent. The displacement was not nearly as significant as with SS cells, confirming our gelation data. Blood group determinations establish that these Arab populations had black African admixture.The Hb OArab/+ Thal double heterozygotes exhibit moderate anemia (10.3g% of Hb) and the percentage of Hb A was 17.2±1.8%. The fetal Hb was 5.4±2.1% and the 2,3-diphosphoglycerate level in two cases was 17.4 mol/g Hb. The only case of a homozygote SS had moderate anemia (10.3 g Hb%), 25.7% of Hb F, and a very benign course. 相似文献
996.
E.A.R. Fontaine D. Abeck A.P. Johnson D. Taylor-Robinson 《FEMS microbiology letters》1987,48(1-2):111-114
Abstract Lipopolysaccharides (LPS) extracted from 33 clinical isolates of Bacteroides ureolyticus were examined by polyacrylamide gel electrophoresis (PAGE) and silver staining. Variable results were obtained with proteinase K-digested whole-cell lysates, but the LPS was shown conclusively to be of the smooth type, exhibiting O side chains, when phenol-water extracts were used. Heterogeneity among the smooth LPS profiles of the strains of B. ureolyticus suggested that such profiles might be useful for typing unknown clinical strains. 相似文献
997.
J A Kissel R N Fontaine C W Turck H L Brockman D Y Hui 《Biochimica et biophysica acta》1989,1006(2):227-236
A full-length cDNA complementary to the rat pancreatic cholesterol esterase mRNA was isolated by screening a rat pancreatic cDNA expression library in lambda gt11 vector with antibodies against the porcine pancreatic cholesterol esterase. The isolated cholesterol esterase cDNA is 2050 bp in length and contains an open reading frame coding for a protein of 612 amino acids. A 20-amino acid hydrophobic leader sequence is predicted, based on the position of the first ATG initiation codon upstream from the sequenced amino terminus of the isolated cholesterol esterase. The cholesterol esterase cDNA was subcloned into a mammalian expression vector, pSVL, for transfection studies. Expression of the cDNA in COS cells resulted in the production of bile salt-stimulated cholesterol esterase. Comparison of the cholesterol esterase cDNA sequence with other proteins revealed that the pancreatic cholesterol esterase is identical to rat pancreatic lysophospholipase. The primary structure of cholesterol esterase displayed no significant homology with other lipases, although the putative lipid interfacial recognition site of G-X-S-X-G is present in the cholesterol esterase sequence. However, the cholesterol esterase sequence revealed a 63-amino-acid domain which is highly homologous to the active site domain of other serine esterases. These data suggest that cholesterol esterase may be a member of the serine esterase supergene family. Analysis of the cholesterol esterase structure also revealed a repetitive sequence enriched with Pro, Asp, Glu, Ser, and Thr residues at the C-terminal end of the protein. This sequence is reminiscent of the PEST-rich sequences in short-lived proteins, suggesting that cholesterol esterase may have a short half-life in vivo. Northern blot hybridization showed that the bile salt-stimulated cholesterol esterase mRNA is present in liver suggesting that this protein may also be synthesized by liver cells. 相似文献
998.
Detection of the nicotinic acetylcholine receptor alpha-subunit mRNA by in situ hybridization at neuromuscular junctions of 15-day-old chick striated muscles. 总被引:34,自引:2,他引:32 下载免费PDF全文
In adult vertebrate striated muscle, the nicotinic acetylcholine receptor (AChR) is almost exclusively localized in the postsynaptic membrane of the neuromuscular junction. Using in situ hybridization, we show that, in two different chicken muscles [the slow multi-innervated anterior latissimus dorsi (ALD) and the fast singly innervated posterior latissimus dorsi (PLD)], the AChR alpha-subunit mRNA is detected at discrete regions on myofibres and that these regions co-localize (80% correspondence) with neuromuscular junctions identified by histochemical staining for acetylcholinesterase. Moreover, autoradiographic grains densely accumulate on and around subsynaptic nuclei. In contrast, hybridization with an actin probe results in a strong signal distributed over the entire length of the myofibres. Denervation increases the level of AChR alpha-subunit mRNA both in the PLD and to a lesser extent in the ALD. By in situ hybridization we observe that, although a perinuclear pattern is maintained, the labelled nuclei appear randomly distributed among approximately 10% of the nuclei. These results are discussed in a model of AChR gene expression in vertebrate striated muscle fibres. 相似文献
999.
E.A. Fontaine D. Abeck A.P. Johnson D. Taylor-Robinson 《Letters in applied microbiology》1988,6(5):117-120
Plasmids were detected in 17 of 24 clinical isolates of Bacteroides ureolyticus. All 17 strains harboured a single large plasmid of ≥24·5 MD but two also had smaller plasmids of 2·3 and 3·9 MD, respectively. The function of the plasmids is unknown. 相似文献
1000.
Abdellatif Chakar Ridha Mokni Philippe Chappuis Jean-Louis Mahu Philip A. Walravens Fanny Bleiberg-Daniel Patrice Therond Jean Navarro Daniel Lemonnier 《Biological trace element research》1993,36(1):25-33
Plasma selenium (Se) concentration and erythrocyte glutathione peroxidase activity (GPx) were assessed in a population of
healthy preschool children two to five years old, residing in the city of Paris. In the 118 subjects, mean (±SD) plasma Se
concentration was 62.10 ±13.96 μg/L, and mean GPx activity was 23.58±8.52 U/g Hb. Mean plasma Se of male children was significantly
(p=0.001) higher (12%) than levels of girls. Plasma selenium levels were not correlated with erythrocyte GPx activity. Children
from Mediterranean origin had a slightly lower erythrocyte GPx activity (p<0.05) than children from other regions. Mean plasma Se concentration of this group corresponded to the lower limit of intervals,
which characterizes geographical regions of intermediate selenium concentrations. 相似文献