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PT Nieh 《Canadian Metallurgical Quarterly》1997,24(4):755-772
The use of detubularized ileum for the Kock pouch produced a low pressure, high capacity system superior to large bowel segments that provided excellent continence and protection of the upper urinary tracts. The early enthusiasm was tempered, however, by the technically demanding aspects of the construction of the nipple valves, the early and late complications, and occasional catheterization problems. With simple modifications in the fixation of the intussuscepted nipples, limiting use of staples and mesh collars, and tapering of the stoma, much of those problems have been resolved. The nipple valve is reliable and superior to the tunneled implant for the dilated ureter. With more widespread indications for continent neobladders, the hemi-Kock reservoir remains one of the most dependable and stable neobladders. 相似文献
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The phenomenology of delirium has received little standardized longitudinal study but offers the prospect of valuable insights regarding clinical subtypes, differentiation from other neuropsychiatric disorders, identification of underlying pathophysiologies, management, and course. This review examines current approaches to the investigation of delirium phenomenology and how the findings to date illuminate our understanding of delirium. It concludes with recommendations for future investigations. 相似文献
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Non-accidental head injury, be it shaking, impact(s) or a combination of the two, is characterised by subdural and/or subarachnoid haemorrhages with retinal haemorrhages, but minimal or absent external cranio-facial trauma. The classical assault scenario depicts the infant being gripped around the head, face, chest and abdomen and shaken or being gripped by a limb and swung. This gripping might be expected to leave physical evidence in the form of bruising. A study was undertaken to establish the prevalence, distribution and pathological association of external bruising in 24 cases of fatal non-accidental head injury in children. At autopsy, 17 cases had new external bruises, 15 old external bruises and 13, a combination of both. However, seven (29%) cases showed no fresh external bruising and five (21%) showed no external bruising at all. Thus, external bruising may be absent in children with fatal intracranial injury. The face was shown to be the commonest site of bruising followed by the forehead and buttocks. Limb, chest and abdominal bruising were found to be uncommon. Retinal haemorrhages were confirmed in 23 (96%) cases. It is hypothesised that bruising, when present, may be a result of abuse in the form of punches and slaps rather than due to gripping during the assault. We discuss why gripping does not necessarily result in external bruising. 相似文献
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RJ Rentenaar PC Wever FN van Diepen TA Out PT Schellekens IJ ten Berge 《Canadian Metallurgical Quarterly》1998,30(8):3958-3959
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PT Castiglia 《Canadian Metallurgical Quarterly》1997,11(1):34-36
This article examines the prediction of risk and dangerousness and identifies aspects relevant to a risk assessment by mental health professionals, in particular nurses. 相似文献
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At birth, the mammalian gastrointestinal tract (GIT) must be able to support a shift from mainly parenteral nutrition in the fetus (via the placenta) to enteral nutrition in the neonate. In the perinatal period the GIT therefore undergoes enhanced growth as well as morphological and functional differentiation, and this maturational programme is influenced by a complex interplay of local, systemic and luminal factors. This review shows how systemic and luminal factors may influence GIT development in the perinatal period of the pig and sheep, two long-gestation species. Adrenocortical hormones play a pivotal role in the prepartum maturation of the GIT in addition to their better known effects on the development of many other tissues and body systems. More particularly, in the fetal pig and sheep, the prenatal development of gastric acid and gastrin secretion, and of GIT hydrolase activities (chymosin, pepsin, amylase, lactase, aminopeptidases) is influenced by cortisol. Additionally, glucocorticoids exert effects throughout the GIT by influencing morphological, cytological, and functional differentiation. Since the GIT epithelial cells comprise a renewing cell population there are also changes in cell kinetics. In addition to systemic factors, the presence of growth factors, hormones and nutrients from swallowed amniotic fluid (fetus) and colostrum (neonate) may influence GIT development. In utero, fetal fluid ingestion has been shown to modulate tissue growth, macromolecule and immunoglobulin transport, enterocyte differentiation, cell turnover and activity of brush-border hydrolases. These effects may be mediated via regulatory peptides (e.g. insulin-like growth factor I, gastrin-releasing peptides, insulin, epidermal growth factor, gastrin). A physiological role of luminally derived growth factors is supported by a number of unique structural and functional adaptations of the GIT in the fetus and neonate (low luminal proteolysis, intestinal macromolecule transport). Thus, in the pig and sheep, both systemic and luminal factors appear to play critical roles in GIT development in the perinatal period. 相似文献
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There is increasing evidence that oxygen-derived free radicals produced during strenuous work by the diaphragm may contribute to diaphragm fatigue and/or injury. However, the precise identity of these oxygen radicals remains unknown, inasmuch as oxygen free radicals are extremely short lived and their detection in biologic systems is quite difficult. There is recent evidence that the salicylate-trapping method may be a useful means of monitoring tissue production of hydroxyl radical (.OH). This method is predicated on the fact that salicylate's phenolic ring can be attacked by .OH at the 3 or 5 position to yield 2,3- or 2,5-dihydroxybenzoic acid (DHB). These metabolites are stable and can be identified by high-performance liquid chromatography (HPLC) coupled with electrochemical or ultraviolet detection. To test the hypothesis that hydroxylated salicylates are produced during diaphragm fatigue, we exposed in vitro rat diaphragm strips to a physiological saline solution containing 2.0 mM sodium salicylate for approximately 15 min. The solution was then removed, and the strips were fatigued (20 Hz, 200-ms train duration, 1 train/s) via phrenic nerve stimulation for 30 s-10 min. The diaphragm strips were subsequently homogenized, and the homogenate was analyzed by HPLC coupled with ultraviolet detection. Levels of 2,3-DHB were significantly higher in fatigued than in control nonfatigued strips. There was also a significant correlation between the amount of 2,3-DHB in the fatigued muscle and the accumulated tension-time product developed during fatigue. 2,5-DHB was not consistently identified in control or experimental strips.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献