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991.
AB Dietz JC Detilleux AE Freeman DH Kelley JR Stabel ME Kehrli 《Canadian Metallurgical Quarterly》1997,80(2):400-405
PURPOSE: Orthotopic lower urinary tract reconstruction has revolutionized urinary diversion following cystectomy. Initially performed solely in male patients, orthotopic diversion has now become a viable option in women. Currently, the orthotopic neobladder is the diversion of choice for women requiring lower urinary tract reconstruction at our institution. We evaluate and update our clinical and functional experience with orthotopic reconstruction in female patients. MATERIALS AND METHODS: Since June 1990, 34 women 31 to 86 years old (median age 67) have undergone orthotopic lower urinary tract reconstruction following cystectomy. Indications for cystectomy included transitional cell carcinoma in 29 patients, urachal adenocarcinoma in 1, mesenchymal tumor of endometrial origin in 1, cervical carcinoma in 1 and a fibrotic radiated bladder in 1. In addition, 1 woman underwent undiversion to the native urethra following a previous simple cystectomy and cutaneous diversion for eosinophilic cystitis. Data were analyzed according to postoperative early and late complications, survival, tumor recurrence, pathological evaluation of the cystectomy specimen, continence status, voiding pattern and patient satisfaction. The median followup in this group of patients was 30 months (range 17 to 70). RESULTS: There were no perioperative deaths, and 4 early (11%) and 3 (9%) late complications. Four patients died, none with a urethral recurrence, including 3 of metastatic bladder cancer and 1 of unrelated causes. In another patient with an extensive mesenchymal tumor of the uterus a sigmoid tumor recurred requiring conversion of the orthotopic reservoir to a cutaneous diversion. All of the remaining 29 patients are alive without evidence of disease. Intraoperative frozen section of the distal surgical margin (proximal urethra) accurately evaluated (confirmed by permanent section) the proximal urethra prospectively for tumor in all 29 specimens removed for transitional cell carcinoma, including 28 specimens (97%) without evidence of tumor and 1 specimen with carcinoma in situ. Complete daytime and nighttime continence was reported by 29 (88%) and 27 (82%) of 33 evaluable patients, respectively. A total of 28 patients (85%) void to completion, while 5 (15%) require some form of intermittent catheterization to empty the neobladder. Patient satisfaction is overwhelming. CONCLUSIONS: The excellent clinical and functional results demonstrated with further followup confirm our initial experience with orthotopic diversion in women. Careful selection of appropriate female candidates for orthotopic diversion is critical, and includes preoperative evaluation of the bladder neck and intraoperative frozen section analysis of the distal cystectomy margin. Furthermore, close monitoring of the retained urethra is mandatory in all women undergoing orthotopic diversion. We believe that the orthotopic neobladder is the urinary diversion of choice in women following cystectomy. 相似文献
992.
993.
VE Miller-Bertoglio S Fisher A Sánchez MC Mullins ME Halpern 《Canadian Metallurgical Quarterly》1997,192(2):537-550
Patterning along the dorsal-ventral (D-V) axis of Xenopus and Drosophila embryos is believed to occur through a conserved molecular mechanism, with homologous proteins Chordin and Short gastrulation (Sog) antagonizing signaling by bone morphogenetic protein 4 (BMP-4) and Decapentaplegic (Dpp), respectively. We have isolated a zebrafish gene that is highly homologous to chordin and sog within cysteine-rich domains and exhibits conserved aspects of expression and function. As in Xenopus embryos, zebrafish chordin is expressed in the organizer region and transiently in axial mesoderm. Injection of zebrafish chordin mRNA to the ventral side of Xenopus embryos induced secondary axes. Ectopic overexpression in zebrafish resulted in an expansion of paraxial mesoderm and neurectoderm at the expense of more lateral and ventral derivatives, producing a range of defects similar to those of dorsalized zebrafish mutants (Mullins et al., 1996). In accordance with the proposed function of chordin in D-V patterning, dorsalized zebrafish mutants showed expanded domains of chordin expression by midgastrulation, while some ventralized mutants had reduced expression; however, in all mutants examined, early organizer expression was unaltered. In contrast to Xenopus, zebrafish chordin is also expressed in paraxial mesoderm and ectoderm and in localized regions of the developing brain, suggesting that there are additional roles for chordin in zebrafish embryonic development. Surprisingly, paraxial mesodermal expression of chordin appeared unaltered in spadetail mutants that later lack trunk muscle (Kimmel et al., 1989), while axial mesodermal expression was affected. This finding reveals an unexpected function for spadetail in midline mesoderm and in differential regulation of chordin expression during gastrulation. 相似文献
994.
G Francica G Marone V D''Angelo G Iodice P Pastore ME Albo G Altamura De Falco A L Sauchelli 《Canadian Metallurgical Quarterly》1997,6(3):185-189
The author describes the most useful anastomosis and resection surgical techniques for the treatment of stenosis of cervical trachea. CO2 laser, dilatation, microsurgery, recalibration by external approach and the use of endotracheal tubes are discussed as well. 相似文献
995.
BACKGROUND: Five randomized trials, a follow-up study, and six case-control investigations of BCG vaccine's effectiveness (VE) for preventing leprosy have been conducted internationally, with widely varying estimates of VE. Because of the difficulty of generalizing from disparate results, local estimates of VE are needed for health planning purposes and are currently particularly relevant, given the World Health Organization's (WHO) goal to eliminate leprosy by the year 2000. METHODS: We conducted a case-control study in Yangon, Myanmar. Residents of Yangon between the ages of 6 years and 24 years who were listed in the National Leprosy Registry as being on active treatment for leprosy between December 1992 and April 1993 were eligible to participate in the study as cases. Control subjects were matched to the cases on age, sex, and neighbourhood. RESULTS: One or more doses of BCG were associated with a VE of 66%. The results show a significant trend of increasing VE with increasing number of BCG doses (one dose, VE = 55%; two doses, VE = 68%; three doses, VE = 87%). One dose of BCG vaccine appeared to provide protection substantially higher than that found in an earlier vaccine trial in Myanmar, but consistent with results from case-control studies in other countries. CONCLUSIONS: These data suggest that BCG reduces the risk of leprosy in Myanmar, and that BCG vaccination of infants, along with early case-finding and treatment, should be considered an important part of the leprosy intervention strategy. 相似文献
996.
997.
998.
Mix design procedure for recycled aggregate concrete 总被引:12,自引:0,他引:12
N. K. Bairagi BCE ME Ph.D. MIE H. S. Vidyadhara B.E. M. Tech Kishore Ravande B.E. M.E. 《Construction and Building Materials》1990,4(4):188-193
Conservation of natural resources and preservation of environment is the essence of any development. Use of recycled aggregate concrete (RAC) is one such attempt and is an answer to some of the problems in constructional engineering. The concept of using RAC is now gaining popularity and research in this direction has gained momentum. In this paper, the authors have identified the most suitable method of mix design for RAC, from amongst the available conventional methods of mix design. An influencing parameter is identified and an empirical relation is suggested to modify the influencing parameter. Mix design parameters thus obtained, enable RAC to attain the desired and designed target strength without attempting any trial mixes. The suggested modified procedure, however, demands 10% more cement which is considered quite reasonable and acceptable in view of the inferior quality of recycled aggregate. 相似文献
999.
KL Komschlies TA Gregorio ME Gruys TC Back CR Faltynek RH Wiltrout 《Canadian Metallurgical Quarterly》1994,152(12):5776-5784
These studies investigate the effects of exogenously administered recombinant human IL-7 (rhIL-7) on mouse leukocyte subsets in vivo in normal and tumor-bearing mice. The administration of rhIL-7 to normal mice caused a pronounced leukocytosis (three- to fivefold increase over background) in the spleen and lymph nodes, with B-lineage and T cells, NK cells, and macrophages all being increased. CD8+ T cells increased disproportionately, such that the CD4 to CD8 ratio decreased dramatically. The rhIL-7-induced effects were dose-dependent, increased with duration of treatment, and were reversible after cessation of rhIL-7 administration. T cell number increases after rhIL-7 treatment were primarily a result of an expansion of the peripheral T cell population. Importantly, splenocytes from rhIL-7-treated mice have enhanced proliferative responses to various T cell stimuli in vitro and were able to potentiate an allogeneic CTL response in vivo. The rhIL-7-induced changes in T cell number and the CD4 to CD8 ratio also were observed in mice bearing early Renca renal adenocarcinoma pulmonary metastases, and these changes coincided with up to a 75% reduction in pulmonary metastases. Overall, these results demonstrate that the administration of rhIL-7 to mice profoundly increases the number of B and T cells, and reduces the number of pulmonary metastases. The results also suggest that IL-7 may be useful for restoring lymphoid subsets in immunosuppressed hosts and in enhancing T cell-mediated immune responses. Such effects may be useful in the treatment of microbial diseases and cancer. 相似文献
1000.
Summary Material conservation and balance laws of elementary beam theory have been derived. The application to beams with discontinuities in the stiffness results in a surprisingly simple formula to calculate stress intensity factors of cracked beams.With 6 Figures 相似文献