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981.
AM Sofou I Diakoyianni-Mordohai AL Pissiotis I Emmanuel 《Canadian Metallurgical Quarterly》1998,29(8):513-516
Severe mandibular alveolar ridge resorption is usually observed in patients with long-term edentulism and/or ill-fitting dentures. In some of these patients, the genial tubercles project into the floor of the mouth as a high point in the anterior area of the mandibular residual ridge. The lingual flanges of mandibular stock impression trays usually impinge on the most prominent areas of the resorbed mandibular edentulous ridge (i.e., internal oblique lines and genial tubercles). It is suggested that a preliminary custom tray be made in such cases to pour an initial impression so that individual custom trays can be fabricated. An efficient method for constructing such a custom impression tray from readily available materials is described. 相似文献
982.
The goals of chemotherapy for recurrent/refractory ovarian cancer are the palliation of disease-related symptoms, and improvement of quality and quantity of life. Previous studies of palliative therapy in advanced ovarian cancer have focused on surrogate measures of patient benefit rather than evaluating palliative end-points such as quality of life and clinical benefit. The impact of palliative chemotherapy on survival, quality of life and cost in advanced ovarian cancer are unknown as there have been no studies comparing palliative treatment with best supportive care. Although there is insufficient information from existing studies to determine whether palliative therapy in advanced ovarian cancer is cost-effective, there is some evidence to suggest that chemotherapy has a role in palliation of symptoms with an apparent improvement in quality of life. We relate the results of two studies. (i) A prospective study evaluating the cost of second/third-line chemotherapy as well as its effectiveness, which found the mean total cost per patient for the study period (one line of chemotherapy) was Canadian $12500. In addition, half of patients seemed to derive some palliative benefit and a quarter of patients had an objective response in their disease. (ii) A retrospective study evaluating all costs from the initiation of palliative chemotherapy until death which demonstrated a cost of Canadian $53000 per patient. Our studies demonstrate that patient expectations of palliative therapy in ovarian cancer are high and patients are willing to put up with significant toxicity for modest benefit. Although palliative therapy may be associated with high costs, even modest prolongation of survival can render such treatment cost-effective. The major cost saving associated with palliative therapy is from the reduced need for hospitalization towards the end of life. Future studies in recurrent/refractory ovarian cancer should focus on palliative end-points and include a comparison with best supportive care. 相似文献
983.
TR Martin GD Rubenfeld JT Ruzinski RB Goodman KP Steinberg DJ Leturcq AM Moriarty G Raghu RP Baughman LD Hudson 《Canadian Metallurgical Quarterly》1997,155(3):937-944
The effects of bacterial endotoxin (lipopolysaccharide, LPS) are amplified by lipopolysaccharide binding protein (LBP) and CD14, resulting in cellular activation at very low concentrations of LPS. To investigate the importance of this pathway in acute lung injury, we measured LPS, LBP, and soluble CD14 (sCD14) in the bronchoalveolar lavage fluid (BAL) of 82 patients with acute respiratory distress syndrome (ARDS). LBP and sCD14 increased markedly in BAL of patients with ARDS. sCD14 and LBP each were strongly related to BAL total protein and polymorphonuclear neutrophil (PMN) concentration, whereas LPS concentration was not. Multivariate analyses showed sCD14 to be strongly related to BAL total protein, even after controlling for LPS and LBP concentrations. sCD14 was strongly and independently related to PMN concentration, after controlling for BAL LPS, LBP, and interleukin-8 (IL-8). The BAL LPS concentration was not strongly related to either BAL total protein or BAL PMN. The BAL sCD14 and LBP values were similar in all subgroups of patients with ARDS, and were not related to survival. The serum LBP and sCD14 were elevated in ARDS, but were not related to BAL total protein, LBP, sCD14, PMN, or clinical outcome. Thus, LBP and sCD14 reach high concentrations in the lungs of patients with ARDS, and BAL sCD14 is strongly related to two major indices of lung inflammation: total protein and PMN concentration. CD14-dependent mechanisms may contribute to lung inflammation in ARDS. 相似文献
984.
JM Kühnel JY Perrot AM Faussat JP Marie MA Schwaller 《Canadian Metallurgical Quarterly》1997,11(7):1147-1155
Multidrug resistance (MDR) is characterized by a decrease in the efficiency of chemotherapeutic agents correlated with the expression and activity of a membrane protein: the permeability-glycoprotein (Pgp 170). Clinically, detection of MDR can be performed by functional tests based on the accumulation of fluorescent compounds such as rhodamine 123. With the aim of improving the sensitivity of such analysis, we have evaluated JC-1, a fluorescent lipophilic carbocyanine dye. Above a critical concentration, JC-1 aggregates in a 'liquid crystal' form. Aggregates display a specific red emission band centered at 597 nm whereas the monomers display a green emission band centered at 540 nm. JC-1 was avidly accumulated in sensitive K562 cells where it displayed both a green cytoplasmic and red mitochondrial fluorescence. In contrast, JC-1 was poorly accumulated in resistant K562 cells, which displayed only a slight green fluorescence. The level of JC-1 accumulation was correlated with the level of Pgp expression detected by MRK16 and UIC2 antibodies on a set of K562 subclones with increasing resistance levels. The specific fluorescence properties of JC-1 allow accurate discrimination between low-level resistant cells and sensitive cells. Chemosensitizers such as verapamil, cyclosporine A or S9788 restored JC-1 accumulation in resistant cells. The fluorescence properties of JC-1 could therefore be used for monitoring the effects of reversing agents. 相似文献
985.
986.
AM Lacy 《Canadian Metallurgical Quarterly》1996,8(3):287-93; quiz 295
Obtaining a firm anatomic contact has been a difficult criteria in placing Class II posterior composite restorations. Various techniques have been developed and a number of products marketed to accomplish this task, but none have combined the necessary qualifications of ease, simplicity, and effectiveness for consistent and predictable results. To address this challenge, two innovative devices--a precontoured (biplanar concave) sectional matrix band and a light--focusing tip-have been developed. Using a clinical case presentation, this article describes the application of these devices to obtain high quality proximal contacts, even in widely separated teeth. The learning objective of this article is to familiarize clinicians with this procedure. The technique is simple and universally applicable with a variety of posterior composite materials and placement methods. 相似文献
987.
Nicotinamide nucleotide transhydrogenase catalyzes the reversible reduction of NADP+ by NADH and a concomitant proton translocation. It was demonstrated (Glavas, N.A. and Bragg, P.D. (1995) Biochim. Biophys. Acta 1231, 297-303) that the Escherichia coli transhydrogenase also catalyzed a reduction of the NAD-analogue 3-acetylpyridine-NAD+ (AcPyAD+) by NADH at low pH and in the absence of (added) NADP(H) and high salt concentrations The mechanism of this reaction has as yet not been explained. In the present study, the E. coli transhydrogenase was purified by affinity chromatography through the NADP(H)-site, rendering the pure enzyme free of NADP(H). Using this preparation it was confirmed that the enzyme readily catalyzes the above reaction. Inhibitors specific for the NADP(H)-site, e.g., palmitoyl-Coenzyme A and adenosine-2'-monophosphate-5'-diphosphoribose, strongly inhibited the reduction of AcPyAD+ by NADH, whereas an inhibitor of the NAD(H)-site, adenosine 5'-diphosphoribose, was less inhibitory. This suggests that a lack of metal ions or other ions at low pH induces an unspecific interaction of the NADP(H)-site with AcPyAD+ or NADH, presumably NADH, producing a cyclic reduction of AcPyAD+ by NADH via NAD(H) bound in the NADP(H) site. A stimulation of reduction of AcPyAD+ by NADPH by Mg2+ present during reconstitution of transhydrogenase in phospholipid vesicles was observed, but it is presently unclear whether this effect is related to that seen with the detergent-dispersed enzyme. 相似文献
988.
C Niederecker B Sauter AM Fürnsinn K Rappersberger 《Canadian Metallurgical Quarterly》1996,47(9):711-715
We report a patient who developed malignant transformation of a cellular blue nevus. At the age of 19 years the congenital, pigmented tumor on the left buttock was histopathologically diagnosed as cellular blue nevus. Thirty years later the tumor dramatically increased in size, involving the entire left buttock within several months. Multiple biopsies revealed the presence of a cellular blue nevus within the papillary dermis and an invasive, pleomorphic pigmented sarcoma in the depth of the tissue spreading into subcutis and skeletal muscle. Both benign and malignant cells were S100+, vimentin+ and HMB-45+, but only the malignant tumor cells stained positive for the proliferating cell nuclear antigen. General examination disclosed multiple metastases in the paraaortal lymph nodes and the retroperitoneum as well as a single brain metastasis. Despite palliative therapy with ionizing radiation and chemotherapy, the patient developed generalized metastases and died within weeks. This case clearly confirms that cellular blue nevi have the potential for malignant transformation and that the malignant variant may behave aggressively just as a malignant melanoma. 相似文献
989.
R Manfredini M Gallerani F Portaluppi R Salmi F Chierici A Tassi E Rizzioli P Notarstefano IS Risichella AM Mirizio C Fersini 《Canadian Metallurgical Quarterly》1996,37(6):829-836
Convincing evidence is now available suggesting that several unfavorable cardiovascular events respect a well-defined diurnal pattern in their occurrence. In particular, ischemic heart disease has been widely investigated, and many data indicate a constellation of underlying risk factors whose temporal coincidence might act as triggering factors in the occurrence of acute events. In this paper, the recent knowledge concerning both epidemiology of ischemic heart disease and potentially favoring factors are reviewed from a chronobiological point of view. 相似文献
990.
C Rae MA Lee RM Dixon AM Blamire CH Thompson P Styles J Talcott AJ Richardson JF Stein 《Canadian Metallurgical Quarterly》1998,351(9119):1849-1852
BACKGROUND: Neurological and physiological deficits have been reported in the brain in developmental dyslexia. The temporoparietal cortex has been directly implicated in dyslexic dysfunction, and substantial indirect evidence suggests that the cerebellum is also implicated. We wanted to find out whether the neurological and physiological deficits manifested as biochemical changes in the brain. METHODS: We obtained localised proton magnetic resonance spectra bilaterally from the temporo-parietal cortex and cerebellum of 14 well-defined dyslexic men and 15 control men of similar age. FINDINGS: We found biochemical differences between dyslexic men and controls in the left temporo-parietal lobe (ratio of choline-containing compounds [Cho] to N-acetylaspartate [NA] p< or =0.01) and right cerebellum (Cho/NA, p< or = 0.01; creatine [Cre] to NA p< or =0.05; (not significant). We found lateral biochemical differences in dyslexic men in both these brain regions (Cho/NA in temporo-parietal lobe, left vs right, p< or =0.01; Cre/NA in cerebellum, left vs right, p< or =0.001). We found no such lateral differences in controls. There was no significant relation between the degree of contralateral chemical difference and handedness in dyslexic or control men. INTERPRETATION: We suggest that the observed differences reflect changes in cell density in the temporo-parietal lobe in developmental dyslexia and that the altered cerebral structural symmetry in dyslexia is associated with abnormal development of cells or intracellular connections or both. The cerebellum is biochemically asymmetric in dyslexic men, indicating altered development of this organ. These differences provide direct evidence of the involvement of the cerebellum in dyslexic dysfunction. 相似文献