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131.
Being a foreign body, intrauterine coil causes decubitus and inflammation of the adjacent tissues. Long-term carriage of the coil may give rise to endometritis, myometritis, parametritis, salpingo-oophoritis, tubo-ovarian inflammatory infiltrates. These infiltrates invade retroperitoneal pelvic fat and may obstruct pelvic ureters. Ureteral obstruction may bring about ureterohydronephrosis, pyelonephritis and renal calculi. The coil may be also responsible for chronic pyelonephritis. The authors have treated 64 females aged 18-45 years with urological complications due to intrauterine coils which stayed from 6 months to 14 years. 34 of them presented with attack of acute pyelonephritis, 29 with renal colic and acute pyelonephritis, 26 with renal calculi. To arrest renal colic and attack of acute pyelonephritis ureteral catheterization and renal pelvis drain were performed in 31 patients. One patient has undergone ureterolithotomy. 8 patients rejected removal of the coil and had recurrent renal colics and acute pyelonephritis attacks. Removal of the coil arrested pyelonephritis and lithogenesis in the kidney. In one case of coil removal there was injury to the uterine cervix and urinary bladder eventuating in vesicovaginal fistula. 相似文献
132.
SK Shapira C McCaskill H Northrup AS Spikes FF Elder VR Sutton JR Korenberg F Greenberg LG Shaffer 《Canadian Metallurgical Quarterly》1997,61(3):642-650
Deletions of the distal short arm of chromosome 1 (1p36) represent a common, newly delineated deletion syndrome, characterized by moderate to severe psychomotor retardation, seizures, growth delay, and dysmorphic features. Previous cytogenetic underascertainment of this chromosomal deletion has made it difficult to characterize the clinical and molecular aspects of the syndrome. Recent advances in cytogenetic technology, particularly FISH, have greatly improved the ability to identify 1p36 deletions and have allowed a clearer definition of the clinical phenotype and molecular characteristics of this syndrome. We have identified 14 patients with chromosome 1p36 deletions and have assessed the frequency of each phenotypic feature and clinical manifestation in the 13 patients with pure 1p36 deletions. The physical extent and parental origin of each deletion were determined by use of FISH probes on cytogenetic preparations and by analysis of polymorphic DNA markers in the patients and their available parents. Clinical examinations revealed that the most common features and medical problems in patients with this deletion syndrome include large anterior fontanelle (100%), motor delay/hypotonia (92%), moderate to severe mental retardation (92%), growth delay (85%), pointed chin (80%), eye/vision problems (75%), seizures (72%), flat nasal bridge (65%), clinodactyly and/or short fifth finger(s) (64%), low-set ear(s) (59%), ear asymmetry (57%), hearing deficits (56%), abusive behavior (56%), thickened ear helices (53%), and deep-set eyes (50%). FISH and DNA polymorphism analysis showed that there is no uniform region of deletion but, rather, a spectrum of different deletion sizes with a common minimal region of deletion overlap. 相似文献
133.
S Giovanni-De-Simone AS Aguiar AR Gimenez K Novellino RS de Moura 《Canadian Metallurgical Quarterly》1997,16(8):809-818
An analytical procedure was developed to measure bromate residues in baked goods using a sequence of clean-up procedures followed by high performance liquid chromatography (HPLC) with a post-column reaction for oxidants. Deionized water was used to extract bromate from bread samples. The extract was treated with a C-18 solid phase extraction column to remove lipids, a cation exchange column with the silver cation to remove chloride, and an ultrafiltration membrane to remove proteins. Further treatment of the extract with the sodium form of a propylsulphonic acid ion exchange column was necessary to remove the silver that leached from the silver column. The method had a detection limit of 3 ng/g in baked goods. Recoveries of bromate from breads ranged from 73 to 86% at a fortified bromate level of 5-100 ng/g. Pullman-type white bread, produced by a sponge and dough method, was prepared in our laboratory for measurement of residual bromate. The dough was scaled in three different weights at different specific volumes (3.8, 4.1, 4.3), and samples of each of the three weights were baked for six different baking times ranging from 24 to 34 min. When bromate at a level of 25 mg/kg was added to flour, no residual bromate was detected in any of the samples, regardless of weight and baking time. 相似文献
134.
AS Dubuisson M Foidart-Dessalle M Reznik JC Grosdent A Stevenaert 《Canadian Metallurgical Quarterly》1997,148(1):378-387
This study reevaluated the possibility of using predegenerated nerves as donor nerve allografts for nerve repair and compared the results of functional recovery to those obtained after standard, fresh nerve allograft repair. Twenty donor rats underwent a ligature/ section of the left sciatic nerve 4 weeks before nerve graft harvesting. Forty recipient rats underwent severing of the left sciatic nerve leaving a 15-mm gap between the nerve stumps. Graft repair was undertaken using either the predegenerated left sciatic nerve of the 20 donor rats (predegenerated group, 20 recipient rats) or the normal right sciatic nerve of the 20 donor rats (fresh group, 20 recipient rats). Recovery of function was assessed by gait analysis, electrophysiologic testing and histologic studies. Walking tracks measurements at 2 and 3 months, electromyography parameters at 2 and 3 months, peroperative nerve conduction velocity and nerve action potential amplitude measurements at 3 months, as well as assessments of myelinated nerve fiber density and surface of myelination showed that fresh and predegenerated nerve grafts induced a comparable return of function although there was some trend in higher electrophysiologic values in the predegenerated group. The only slight but significant difference was a larger mean nerve fiber diameter in the nerve segment distal to a predegenerated nerve graft compared to a fresh nerve graft. Although our study does not show a dramatic long-term advantage for predegenerated nerve grafts compared to fresh nerve grafts, their use as prosthetic material is encouraging. 相似文献
135.
GP Rossi G Albertin S Bova AS Belloni F Fallo U Pagotto L Trevisi G Palù AC Pessina GG Nussdorfer 《Canadian Metallurgical Quarterly》1997,138(10):4421-4426
136.
G Gourdon P Dessen AS Lia C Junien H Hofmann-Radvanyi 《Canadian Metallurgical Quarterly》1997,40(2):73-77
The ultrastructural morphology of the interface region between the stria vascularis (SV) and spiral ligament (SL) was examined in the neonatal rat cochlea via transmission electron microscopy. At postnatal day (PND) 3, morphology of both basal cells and fibrocytes was simple and immature. Only a small number of fibrocytes was observed in the SL. Intercellular junctions between basal cells and fibrocytes, and between adjacent fibrocytes, were few. At PND 7, the number of fibrocytes increased, and more organelles appeared within their cytoplasm. From PND 11 to 14, nuclei of the basal cells appeared to be more spindle-shaped and contained more heterochromatin. The cytoplasm of the fibrocytes was pale, and a greater number of cytoplasmic vesicles and mitochondria emerged. More intercellular junctions were observed between basal cells and fibrocytes at the interface region and between fibrocytes in the SL. By PND 21, the morphology of basal cells and fibrocytes and their intercellular junctions appeared to be adult-like. These morphological observations correlate with previous reports on the functional maturation of the developing rat cochlea. 相似文献
137.
D Reddy AS Pollock SA Clark K Sooy RC Vasavada AF Stewart T Honeyman S Christakos 《Canadian Metallurgical Quarterly》1997,94(5):1961-1966
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青海盐湖钾资源平衡开采研究 总被引:2,自引:0,他引:2
钾资源是一种战略资源,钾肥的生产关系到国家粮食安全。近年来中国钾肥需求缺口不断增大,钾肥产量也在逐年增加,导致钾资源被单一、片面地开采,直接影响盐湖资源综合利用和平衡开采。在分析青海钾资源开发利用的基础上,通过计算分析对钾资源的平衡开采进行了研究,确定了青海钾肥的合理开采量,有助于实现钾资源开发利用的可持续性。 相似文献