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81.
Rebecca Suckling Mohamed Morsy Eric S Chemla 《Nephrology, dialysis, transplantation》2007,22(3):970-971
Sir, The expansion of haemodialysis includes older patients withcomorbidities, poor quality vessels, unsuitable for transplantationor peritoneal dialysis. Vascular access complications accountfor 20% of hospital admissions [1]. With exhausted sites inupper extremities, unusual sites for arteriovenous grafts formationare used [2]. The 相似文献
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83.
Background : Bladder augmentation may be undertaken by using various gastrointestinal segments but their use is associated with a multitude of well-recognized complications. The mega-ureter has proven to be a satisfactory alternative; in patients with bilateral mega-ureters, both ureters may be used for this purpose. Methods : Seventeen patients had augmentation ureterocystoplasty, including three in whom both distal ureters were used in tandem. The latter included two patients with neurogenic bladder and one with bladder exstrophy. Results : Satisfactory augmentation was achieved in all patients undergoing tandem ureterocystoplasty. The neurogenic bladder patients are managed by urethral clean intermittent catheterization (CIC) and the exstrophy patient is managed by CIC of an appendico-vesicostomy (Mitrofanoff). All are continent. Conclusions : The mega-ureter provides an excellent source of augmentation material in patients with small non-compliant bladders. In those with bilateral mega-ureters, consideration should be given to using both ureters in tandem to achieve the maximum possible bladder capacity. 相似文献
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86.
Daher A de Boer WI El-Marjou A van der Kwast T Abbou CC Thiery JP Radvanyi F Chopin DK 《Laboratory investigation; a journal of technical methods and pathology》2003,83(9):1333-1341
Members of the epidermal growth factor (EGF) family and their receptors are involved in many cellular processes, including proliferation, migration, and differentiation. We have previously reported that these growth factors are expressed and have specific regulatory functions in an organ-like culture model of normal human urothelial cells. Here, we used this model to investigate the involvement of EGF receptor (EGFR) in human urothelial regeneration. Three 4-mm-diameter damaged areas were made in confluent normal human urothelial cell cultures with a biopsy punch. Regeneration was measured, on fixed stained cultures, with an image analyzer, at 4, 24, and 48 hours after injury. Cell proliferation was assessed by 5-bromo-2-deoxyuridine incorporation. To identify EGF family factors potentially involved in the healing process, we studied the effect of these factors on damaged confluent cultures and the level of expression of mRNAs extracted from these cultures. EGFR inhibition of the proliferation and migration of urothelial cells was tested with (1). a specific tyrosine kinase inhibitor (AG1478) and (2). a blocking anti-EGFR antibody (LA22). Exogenously added amphiregulin, EGF, transforming growth factor-alpha and heparin-binding EGF (HB-EGF) stimulated urothelial regeneration. The damaged areas were repaired by regrowth within 48 hours. Both AG1478 and LA22 inhibited the repair (by 50% and 30%, respectively), as well as proliferation and migration. This regeneration was accompanied by increased HB-EGF mRNA expression in cultures of cells from four of six subjects, but no corresponding change in EGFR protein level was observed. These results indicate that the EGFR signaling pathway is involved in urothelial regeneration. Our data support an autocrine role of HB-EGF in this process and suggest that the EGFR pathway is a potential therapeutic target for modulating urothelial cell proliferation. 相似文献
87.
Six examples of histologically diagnosed, non-invasive breast carcinomas were studied by electron microscopy to elucidate the ultrastructural features for an accurate diagnosis of in situ carcinoma. The results obtained revealed two patterns of basal lamina/stromal cells relationship. One pattern showed intact basal lamina with associated periductal stromal cells consisting entirely of fibroblasts, the other pattern showed disruption of basal lamina by gaps and malignant cell protrusions with associated stromal cells consisting of both fibroblasts and myofibroblasts. As myofibroblasts are not a component of normal breast stroma but are known to be a prominent feature in the stroma of infiltrating breast carcinoma, the present observations suggest that myofibroblastic proliferation around in situ carcinoma represents an early sign of carcinomatous infiltration. Hence the definitive diagnosis of non-invasive carcinoma of the breast requires an intact basal lamina and a complete absence of a myofibroblastic reaction. 相似文献
88.
Zahir Ahmed 《Parasitology research》1959,19(1):67-99
Ohne ZusammenfassungMit 8 Textabbildungen in 21 Einzeldarstellungen 相似文献
89.
A. Razzaque Ahmed Richard I. Murahata Robert W. Schroff Ronald M. Stevens Andrew S. Saxon 《Journal of clinical immunology》1983,3(3):241-252
T cells from nine patients in the active stage of pemphigus vulgaris and five in the inactive stage of the disease were studied with Leu-1, Leu-2, and Leu-3 monoclonal antibodies. No significant differences were observed in the proportions of total T cells or T cells expressing either helper or suppressor phenotype in peripheral blood leukocytes of patients compared to normal subjects. Immunoregulatory mechanisms were functionally studied using an assay measuring total IgG synthesizedin vitro. Peripheral blood leukocytes were separated into T- and B-cell fractions and cultured in various combinations. In nine experiments, the T cells were irradiated prior to culturing with B cells to remove their suppressor function. No statistically significant differences were observed in the total IgG synthesized by B cells obtained from patients and normal subjects when cultured with untreated T cells or irradiated T cells obtained from patients or normal controls. These results indicated that there was no loss of suppressor-cell function or increased helper-cell function when assessed by measuring the total IgG synthesized. The addition of serum from pemphigus patients to peripheral blood leukocyte cultures of pemphigus patients and normal controls had no statistically significant effect on the synthesis of total protein or on the amount of Ig synthesized and secreted. Peripheral blood leukocytes from six untreated patients with pemphigus vulgaris were stimulatedin vitro with pokeweed mitogen (PWM) to produce immunoglobulin. The IgG produced selectively bound to the intercellular cement substance of the epidermis of patients' perilesional skin, normal human skin, and monkey esophagus. The IgG was biosynthetically labeled by culturing the leukocytes in medium supplemented with [3H]leucine, and the binding of the radiolabeled IgG was visualized by autoradiography. The IgG nature of the protein was demonstrated by precipitation withStaphylococcus protein A and removal with rabbit anti-human IgG antisera. Peripheral blood leukocytes obtained from normal volunteers and control patients did not produce this antibody. Our studies indicate that there was no general functional or phenotypic alteration of suppressor or helper T cells in the peripheral blood. The peripheral blood leukocytes of pemphigus patients under PWM stimulation can produce an anti-intercellular cement substance antibodyin vitro. These results indicate that the abnormality of immunoregulation which resulted in the production of a pathogenetic autoantibody in pemphigus is highly specific. 相似文献
90.
Inactivation of Notch1 impairs VDJbeta rearrangement and allows pre-TCR-independent survival of early alpha beta Lineage Thymocytes 总被引:12,自引:0,他引:12
Notch proteins influence cell fate decisions in many developmental systems. During lymphoid development, Notch1 signaling is essential to direct a bipotent T/B precursor toward the T cell fate, but the role of Notch1 at later stages of T cell development remains controversial. We have recently reported that tissue-specific inactivation of Notch1 in immature (CD44(-) CD25(+)) thymocytes does not affect subsequent T cell development. Here, we demonstrate that loss of Notch1 signaling at an earlier (CD44(+)CD25(+)) developmental stage results in severe perturbation of alpha beta but not gamma delta lineage development. Immature Notch1(-/-) thymocytes show impaired VDJ beta rearrangement and aberrant pre-TCR-independent survival. Collectively, our data demonstrate that Notch1 controls several nonredundant functions necessary for alpha beta lineage development. 相似文献