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211.
Nasal masks for domiciliary positive pressure ventilation: patient usage and complications. 总被引:2,自引:1,他引:1 下载免费PDF全文
BACKGROUND--Nasal mask discomfort is a major factor in compliance with treatment by nasal intermittent positive pressure ventilation (NIPPV) and nasal continuous positive airway pressure (CPAP). METHODS--A study of skin complications resulting from mask usage, with particular reference to predisposing factors, was carried out in 66 patients by means of a postal questionnaire. An effective means of managing ulceration at the nasal bridge while continuing therapy is described. RESULTS--Some disruption of treatment due solely to mask discomfort was experienced by 35 patients (53%), consisting of broken skin or open sores in 11 cases (17%). CONCLUSIONS-Although complications resulting from nasal mask usage are common, early identification of patients at risk of developing such complications and appropriate intervention will result in improved patient compliance. 相似文献
212.
Precise and limited decompression for lumbar spinal stenosis 总被引:3,自引:0,他引:3
Summary Fifty-eight consecutive patients with lumbosacral nerve root entrapment due to spinal stenosis were treated with modified microsurgical decompression. Only the clinically relevant sides and levels were decompressed while the spinous processes, the interspinous ligaments, the medial portion of ligamentum flavum and the functionally important parts of the facet joints were preserved. The reviewers rated recovery as good or excellent in 71% of patients while patient self-assessment indicated 76% good or excellent outcome. These data suggest that microsurgical decompression of spondyloarthritic changes can effectively relieve the signs and symptoms of nerve root compression and that with careful evaluation of all available data the number of nerve roots requiring decomperession is often fewer than what is suggested by diagnositic images alone. 相似文献
213.
214.
In situ hybridization histochemistry revealed three different ontogenetic patterns of localized expression of the high-affinity type of neurotensin receptor mRNA in the developing rat brain: one comprises sites which showed transient expression of neurotensin receptor mRNA during the first postnatal week, the expression greatly decreasing thereafter (type I); another comprises sites at which there is a gradual increase in neurotensin receptor mRNA after birth, as there is in cell number and intensity, with advancing age, followed by a plateau (type II); the third comprises sites at which there is much expression of neurotensin receptor mRNA already at birth, and a slight decrease thereafter (type III). The cerebral cortex, except retrosplenial and entorhinal cortices, and the anterior dorsal thalamic nucleus exhibit the type I pattern, while the horizontal and vertical limbs of the diagonal band of Broca, magnocellular preoptic nucleus, substantia innominata, ventral part of the suprachiasmatic nucleus, medial habenular nucleus, ventral tegmental area and substantia nigra pars compacta exhibit the type II pattern. The tenia tecta, retrosplenial and entorhinal cortices exhibit the type III pattern. One of the most striking findings in this study was that the entire neocortex and most of the limbic cortex exhibit the type I pattern, i.e. neurotensin receptor mRNA is expressed transiently long before a neuronal network is established there. This suggests that neurotensin plays an important role in cortical development, other than its reported transmitter-like role in the adult. 相似文献
215.
C Schmitt J Brachmann W Saggau T Beyer B Waldecker K Scharowski T Hilbel M Montero B Offner W Sch?ls 《Zeitschrift für Kardiologie》1991,80(11):665-672
In 41 patients with recurrent sustained ventricular tachycardia and/or ventricular fibrillation an integrated pacemaker-defibrillator-system (PCD, Medtronic, model 7216 A or 7217 B) was implanted. In 21 out of 24 (88%) patients a new transvenous implantation technique in combination with a subcutaneous patch electrode was used. The implanted devices comprise antibradycardiac pacemaker functions, two different forms of antitachycardiac pacemaker functions (ramp and burst pacing), and internal cardioversion or defibrillation capabilities. During a mean follow-up of 8 months 147 episodes of ventricular tachycardia were detected, 131 of them were terminated successfully by antitachycardiac pacing; in 13 episodes internal cardioversion was applied to revert ventricular tachycardia. Twenty-seven episodes of ventricular fibrillation or rapid ventricular tachycardia (greater than 200/min) were detected and successfully terminated by internal defibrillation. In six patients with intermittent rapid atrial fibrillation, change of antiarrhythmic therapy was required to avoid activation of the device. The new integrated pacemaker-defibrillator systems improve therapy in patients with life-threatening tachyarrhythmias by reducing the number of internal cardioversions/defibrillations; the non-thoracotomy approach reduces the post operative risk. 相似文献
216.
217.
This report describes the intracellular metabolism of 5-formyltetrahydrofolate into the various one-carbon substituted folate and polyglutamate pools in a human breast (MCF-7) and colon (HCT 116) carcinoma cell line. Metabolism into the one-carbon substituted pools was found to be time and dose dependent over a concentration range up to 50 microM. A 3-fold increase in total intracellular folate was noted over a 50-fold concentration range (1-50 microM) of 5-formyltetrahydrofolate tested in the colon cell line, while in the breast line, a 6-fold increase was detected over a 500-fold concentration range (0.1-50 microM). The level of 5, 10-methylenetetrahydrofolate, which was detectable only in the breast cell line, was found to increase by a factor of 10 (1.8 pmol/mg to 17.9 pmol/mg) over the concentration range studied. The majority of metabolism was into the 10-formyltetrahydrofolate and tetrahydrofolate pools in the breast cells and into the 5-methyltetrahydrofolate pool in the colon cells. Polyglutamation was also time and dose dependent, with a significant proportion of the total pool represented by the higher polyglutamate forms (Glu3-Glu5) after 24 h of continuous exposure to 5-formyl tetrahydrofolate. Pentaglutamate was the highest level noted in both cell lines. The intracellular half-life of the polyglutamate forms was inversely related to the length of the polyglutamate tail with half-lives of 71, 131, 143, 441, and 1167 min for the mono- through pentaglutamate, respectively. Finally, up to a 20:1 ratio of the biologically inactive (6R) isomer to active (6S) isomer of 5-formyltetrahydrofolate resulted in no effect on metabolism into the one-carbon substituted folate pools and only minimal decreases in metabolism to the polyglutamate forms. These studies suggest that prolonged exposure to even relatively low doses of 5-formyltetrahydrofolate may be optimal for intracellular metabolism to the most biologically relevant forms for ternary complex formation with thymidylate synthase and fluorodeoxyuradylate, since longer exposures result in a greater accumulation of the higher polyglutamates. 相似文献
218.
219.
Of 431 patients with gastric cancer observed in our institution, 23 (5.3%) had early gastric cancer (EGC). Macroscopic presentation, histology, depth of invasion, and lymph node involvement were evaluated in all the cases. All patients underwent surgery and an intensive follow-up was performed. Five of the 23 patients progressed, and the risk factors were examined. Histology seemed to be the main prognostic factor in our study, since intestinal type of EGC was associated to a significantly better prognosis. Total gastrectomy is indicated in the proximal localization of EGC, and should perhaps be performed also in cases presenting undifferentiated histology. 相似文献
220.
The anticarcinogenic action of the garlic constituent diallyl sulfide (DAS), was examined in the hamster buccal pouch and forestomach. Groups of hamsters were topically treated, for up to 14 weeks, with a 0.5% solution of the buccal pouch and forestomach carcinogen 7,12-dimethylbenz[a]anthracene (DMBA). Prior to, during and after DMBA treatment, groups of hamsters were also treated, on alternate days, with a 1% solution of DAS. In addition to tumor formation, the induction of gamma-glutamyl transpeptidase (gamma GT) buccal pouch epithelial lesions served as an additional presumptive index of in vivo carcinogenesis/anticarcinogenesis. DAS resulted in a significant reduction in buccal pouch tumor frequency, buccal pouch tumor burden, buccal pouch gamma GT lesion frequency and forestomach tumor frequency. In a separate experiment, DAS also reduced the level of autoradiographically quantified unscheduled DNA repair synthesis (UDS) in pieces of hamster buccal pouch concurrently exposed in vitro to the potent buccal pouch carcinogen N-methyl-N-benzylnitrosamine (MBN). This study demonstrates that DAS is an effective anticarcinogenic agent in squamous mucosa of the hamster and suggests novel cost-effective strategies for the rapid identification of tissue-specific anticarcinogens and a quantitative assessment of their efficacy. 相似文献