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Geoffrey Rowden Shirley Dean James Campbell Philip Belitsky 《Microscopy research and technique》1985,2(6):547-555
Aspiration biopsy of tumors and transplanted organs is a popular atraumatic method for diagnosis and also for the management of patients. Apart from the cytological analyses, it is clear that large aggregates of cells are obtained and these may be examined by electron microscopy. A study was carried out with dogs to assess the yield of intact glomeruli and tubules, resulting from a standard fine-needle aspiration procedure. Employing a 20-gauge needle, yields of approximately ten intact glomeruli were obtained with a tissue processing protocol that utilized filtration through a nylon mesh and backwashing, to resuspend the trapped aggregates. Processing for electron microscopy was carried out in microcentrifuge tubes. The ultrastructural preservation was excellent and the extension of these studies to investigations of not only renal transplantation, but also for diagnosis in human renal diseases of a broad spectrum, is suggested. 相似文献
3.
P. C. Campbell E. B. Hawbolt J. K. Brimacombe 《Metallurgical and Materials Transactions A》1991,22(11):2769-2778
The goal of this study was to develop a mathematical model which incorporates heat flow, phase transformation kinetics, and
property-structure-composition relationships to predict the mechanical properties of steel rod being control cooled under
industrial conditions. Thus, the principles of microstructural engineering have been brought to bear on this interdisciplinary
problem by combining computer modeling with laboratory measurements of heat flow, austenite decomposition kinetics, microstructure
and mechanical properties, and industrial trials to determine heat transfer and obtain rod samples under known conditions.
Owing to the length and diversity of the study, it is reported in three parts,[8191]the first of which is concerned with the heat flow measurements. A relatively simple and reliable technique, involving a preheated
steel rod instrumented with a thermocouple secured at its centerline, has been devised to determine the cooling rate in different
regions of the moving bed of rod loops on an operating Stelmor line. The measured thermal response of the rod has been analyzed
by two transient conduction models (lumped and distributed parameter, respectively) to yield overall heat-transfer coefficients
for radiation and convection. The adequacy of the technique has been checked by cooling instrumented rods under well-defined,
air crossflow conditions in the laboratory and comparing measured heat-transfer coefficients to values predicted from well-established
equations. The industrial thermal measurements have permitted the characterization of a coefficient to account for radiative
interaction among adjacent rod loops near the edge and at the center of the bed.
Formerly Graduate Student, The University of British Columbia. 相似文献
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MJ Glantz PC Burger AH Friedman RA Radtke EW Massey SC Schold 《Canadian Metallurgical Quarterly》1994,44(11):2020-2027
When radiation is used to treat nervous system cancer, exposure of adjacent normal nervous system tissue is unavoidable, and radiation-induced injury may occur. Acute injury is usually mild and transient, but late forms of radiation-induced nervous system injury are usually progressive and debilitating. Treatment with corticosteroids, surgery, and antioxidants is often ineffective. We treated 11 patients with late radiation-induced nervous system injuries (eight with cerebral radionecrosis, one with a myelopathy, and two with plexopathies, all unresponsive to dexamethasone and prednisone) with full anticoagulation. Some recovery of function occurred in five of the eight patients with cerebral radionecrosis, and all the patients with myelopathy or plexopathy. Anticoagulation was continued for 3 to 6 months. In one patient with cerebral radionecrosis, symptoms recurred after discontinuation of anticoagulation and disappeared again after reinstitution of treatment. We hypothesize that anticoagulation may arrest and reverse small-vessel endothelial injury--the fundamental lesion of radiation necrosis--and produce clinical improvement in some patients. 相似文献
7.
PURPOSE: We describe a new method of using a Foley catheter to assist vesicourethral anastomosis during radical retropubic prostatectomy. MATERIALS AND METHODS: A total of 81 patients underwent radical retropubic prostatectomy with this technique. Followup ranged from 4 to 48 months. Peri-catheter urethrograms were performed at 3 weeks. Patients were evaluated specifically for bladder neck contracture, urinary continence and prolonged catheterization. RESULTS: Bladder neck contracture, occurred in 4.9% of the patients and 87.6% were completely continent of urine. Only 1 patient required extended postoperative catheterization. CONCLUSIONS: Use of a Foley catheter for vesicourethral anastomosis is consistent and simple, and provided good surgical results in our experience. 相似文献
8.
RA Kerr 《Canadian Metallurgical Quarterly》1998,282(5395):1807-1809
9.
RA Kilani P Hmiel MK Garver SK Srinathan KM Wickline JC Langer 《Canadian Metallurgical Quarterly》1996,31(10):1427-1429
Although jejunal atresia occasionally may occur with a familial pattern, an association with renal disease has not been described. The authors report on three family members treated over two generations, all of whom had both proximal jejunal atresia and renal dysplasia. This association was most likely inherited as an autosomal dominant trait. 相似文献
10.