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Unidirectional fluxes of 45Ca, 36Cl, and of [3H]mannitol from blood into the sciatic nerve and cerebral cortex were determined from 5- and 15-min uptakes of these tracers after an intravenous (i.v.) bolus injection in awake rats. Rats were fed diets for 8 wk, that had either a low (0.01% wt/wt), normal (0.67%), or high (3%) Ca content. Plasma [Ca] was 32% less and 11% more in rats fed low (LOCA) and high Ca diets (HICA), respectively, than in rats fed a normal Ca diet (CONT). The mean permeability-surface area product (PA) of 45Ca at the blood-nerve barrier was about eightfold higher than at the blood-brain barrier in the same animals and did not differ significantly between groups (greater than 0.05). Mean PA ratios of 45Ca/36Cl for the blood-nerve and blood-brain barriers in CONT rats, 0.52 +/- 0.04 and 0.40 +/- 0.02, respectively, were not significantly different from corresponding ratios in LOCA and HICA groups, and corresponded to the aqueous limiting diffusion ratio (0.45). Our results show no evidence for concentration-dependent transport of Ca over a plasma [Ca] range of 0.8-1.4 mmol/liter at the blood-nerve barrier of the rat peripheral nerve, and suggest that Ca and Cl exchange slowly between nerve and blood via paracellular pathways.  相似文献   
3.
Lobster-Claw syndrome is a rare autosomal dominant, hand-foot malformation with Oro-dental features. This is a rare condition and from the available reports so far, cases being reported are less than 1%. Most reports have focused on the hand-foot deformity of this syndrome. This paper highlights the typical Oro-dental features associated with this syndrome such as retained deciduous teeth, hypodontia and variation in crown size, arch length and arch width.  相似文献   
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Design and real‐time validation of a robust fixed‐order H2 optimal controller for micro aerial vehicle, named Sarika‐2, is presented. Strengthened discrete optimal projection equations, which approximate the first‐order necessary optimality condition, are used for the controller design. Effect of low‐frequency gust disturbance and high‐frequency sensor noise is alleviated through the output sensitivity and control sensitivity minimization. The novelty of this paper is that a single robust H2 controller, which is designed at the central operating point, ensures simultaneous stabilization of the radio‐controlled aircraft over the entire cruise speed range of 16–26 m/s. The controller is implemented on a digital‐signal‐processor‐based flight computer, and subsequently, it is validated through the real‐time hardware‐in‐loop‐simulation. The responses obtained from the hardware‐in‐loop‐simulation compares well with those obtained from the off‐line simulation. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
6.
Bronchodilator therapy on inspiratory indices has not been documented so far. Reduction in inspiratory airflow resistance following inhalation of bronchodilator giving the most consistent and significant changes in emphysematous patients has been demonstrated in the present study.  相似文献   
7.
The goal of this study is to develop unique native endothelium mimicking nanomatrices and evaluate their effects on adhesion and spreading of human umbilical vein endothelial cells (HUVECs) and aortic smooth muscle cells (AoSMCs). These nanomatrices were developed by self-assembly of peptide amphiphiles (PAs) through a solvent evaporation technique. Three PAs, one containing the Tyr-Ile-Gly-Ser-Arg (YIGSR) ligand, the second containing the Val-Ala-Pro-Gly (VAPG) ligand, and a third without cell adhesive ligands, were developed. Cell adhesion and spreading were evaluated by a PicoGreen-DNA assay and live/dead assay, respectively. Our results show that PA-YIGSR significantly enhances HUVEC adhesion (26,704 ± 2708), spreading (84 ± 8%), and proliferation (50 ± 2%) compared with that of other PAs. PA-VAPG and PA-YIGSR showed significantly greater AoSMC adhesion compared with that of PA-S. PA-VAPG also showed significantly greater spreading of AoSMCs (63 ± 11%) compared with that of other PAs. Also, all the PAs showed significantly reduced platelet adhesion compared with that of collagen I (control). These findings would facilitate the development of novel vascular grafts, heart valves, and cell-based therapies for cardiovascular diseases.From the Clinical EditorThe goal of this study was to develop unique native endothelium mimicking nanomatrices and evaluate their effects on adhesion and spreading of human umbilical vein endothelial cells (HUVECs) and aortic smooth muscle cells (AoSMCs). These nanomatrices were developed by self-assembly of peptide amphiphiles through a solvent evaporation technique. The findings are expected to facilitate the development of novel vascular grafts, heart valves, and cell based therapies for cardiovascular diseases.  相似文献   
8.
An immunohistochemical method is described for identification of myoepithelial cells and basement membrane for cryostat tissue sections of normal, benign, and in situ carcinomas of the breast using two monoclonal antibodies 155C1 and 155D10 generated against human breast carcinosarcoma cell line HS578T. In the majority of infiltrating ductal carcinomas of the breast, there was a discontinuity in the myoepithelial cell layer, as a result an intact basement membrane could not be visualized. The reactivity of these two monoclonal antibodies might prove useful in the study of myoepithelial differentiation antigens and in the delineation of basement membrane. Among the other types of tissues studied, prominent staining was present with soft tissue tumors like leiomyosarcoma and synovial sarcoma.  相似文献   
9.
Monoclonal antibody CIBCNSH3 of IgG1 isotype has been generated against human epidermal growth factor receptor (EGFR) using MDA MB 468 breast carcinoma cell line as immunogen. Earlier studies have revealed that this MAb blocked growth factor-receptor interaction and thus inhibited cell proliferation and tumor growth. In the present paper, this MAb has been extensively characterized to evaluate its application in the study of human cancers. The results were compared with those obtained using a control MAb ICR 62 specific to EGFR. Competitive assay showed that this MAb bound to an epitope in the extracellular domain of the EGFR to which MAb ICR 62 also bound. This MAb immunoprecipitated the 170 kD glycoprotein. The specificity was further confirmed by the formation of a single discrete band in western blot analysis. By flow cytometric analysis this monoclonal antibody revealed high binding affinity with MDA MB 468 cells. By immunocytochemical assay, out of 35 breast tumors studied, 40% were found to exhibit strong cell membrane staining and in the case of 25 oral cancers studied, 56% were strong positive. High expression of EGFR was observed in MDA MB 468 cells and HN 5 cells. These studies clearly indicate that MAb CIBCNSH3 might prove useful to identify tumors with high level of expression of EGFR associated with poor prognosis.  相似文献   
10.
Fanconi anemia (FA) is a genetic disorder characterized by hypersensitivity to DNA damage, bone marrow failure, congenital defects, and cancer. To further investigate the in vivo function of the FA pathway, mice with a targeted deletion in the distally acting FA gene Fancd2 were created. Similar to human FA patients and other FA mouse models, Fancd2 mutant mice exhibited cellular sensitivity to DNA interstrand cross-links and germ cell loss. In addition, chromosome mispairing was seen in male meiosis. However, Fancd2 mutant mice also displayed phenotypes not observed in other mice with disruptions of proximal FA genes. These include microphthalmia, perinatal lethality, and epithelial cancers, similar to mice with Brca2/Fancd1 hypomorphic mutations. These additional phenotypes were not caused by defects in the ATM-mediated S-phase checkpoint, which was intact in primary Fancd2 mutant fibroblasts. The phenotypic overlap between Fancd2-null and Brca2/Fancd1 hypomorphic mice is consistent with a common function for both proteins in the same pathway, regulating genomic stability.  相似文献   
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