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61.
Primary mucosal malignant melanoma of the head and neck 总被引:4,自引:0,他引:4
Patel SG Prasad ML Escrig M Singh B Shaha AR Kraus DH Boyle JO Huvos AG Busam K Shah JP 《Head & neck》2002,24(3):247-257
INTRODUCTION: The relative rarity of mucosal melanomas of the head and neck (MMHN) has made analysis of treatment approaches difficult. Advances in diagnostic techniques and treatment interventions have had obvious impact on outcomes in cutaneous melanoma, but the effects on outcome in MMHN remain undefined. This study aims to assess the outcome and identify clinical and histologic prognostic indicators in a recent cohort of patients with MMHN treated at a single institution. METHODS: The clinical records of 59 patients with the diagnosis of MMHN treated at Memorial Sloan-Kettering Cancer Center (MSKCC) between 1978 and 1998 were retrospectively reviewed. Pathologic material on each of these patients was prospectively reviewed by at least two pathologists (MP, KB, or AH) for confirmation of diagnosis and assessment of histologic variables. Survival was calculated by the Kaplan-Meier method. Clinical (patient demographics, tumor characteristics, and treatment) and histologic data (tumor thickness, melanosis, melanoma in situ, vascular invasion, and multifocality) were analyzed for impact on outcome by both univariate and multivariate analyses. RESULTS: Thirty-five patients (59%) had sinonasal tumors (SNMM), whereas 24 (41%) had oral (ORMM) tumors. Forty-seven patients (79.6%) were staged as stage I, 8 (13.6%) as stage II, and 4 (6.8%) were classified as stage III. Regional lymphatic metastases at presentation were more frequent in ORMM compared with SNMM (25% vs 6%, p =.05). Surgery was used in all patients. Adjuvant radiation therapy was used more frequently in the SNMM group compared with the ORMM group (40% vs 17%, p =.04). The rates of local failure for ORMM and SNMM were 51% and 50%, nodal failure rates were 42% and 20%, and distant failure rates were 67% and 40%, respectively (p = NS). With a median follow-up of 20 months, the 5-year disease-specific survival rate was 44% (40% for ORMM vs 47% for SNMM, p = NS). Significant prognostic factors for disease-specific survival on univariate analysis included advanced clinical stage at presentation, tumor thickness greater than 5 mm, presence of vascular invasion, and development of nodal and distant metastases. On multivariate analysis, however, regional nodal failure lost significance. CONCLUSIONS: Clinical stage at presentation, tumor thickness greater than 5 mm, vascular invasion on histologic studies, and development of distant failure are the only independent predictors of outcome in MMHN. 相似文献
62.
Esi Colecraft Grace S. Marquis Richmond Aryeetey Owuraku Sakyi-Dawson Anna Lartey Benjamin Ahunu Emmanuel Canacoo Lorna M. Butler Manju B. Reddy Helen H. Jensen Elisabeth Huff-Lonergan 《Ecology of food and nutrition》2006,45(5):351-377
Micronutrient deficiencies limit child health and development. Although animal source foods (ASF) provide highly bioavailable micronutrients, Ghanaian preschoolers consume little. Participatory rapid appraisal methods identified constraints to the availability, accessibility, and utilization of ASF. Stakeholders working with or living in six communities in three agro-ecological zones reported constraints including low income, lack of access to technology and markets, inequitable household food allocation, inadequate knowledge, and beliefs. The least expensive ASF was fish, which was easy to preserve and consumed by all communities. Since ASF was primarily purchased, interventions that increase income may be most successful in improving Ghanaian children's diets. 相似文献
63.
Fraser or Cryptophthalmos syndrome is a variable syndrome to the extent that cryptophthalmos might not be present in all cases.
However, the main features are a “hidden eye”, other craniofacial abnormalities, renal abnormalities, syndactyly and abnormal
genitalia. It may be classified as isolated cryptophthalmos or cryptophthalmos sequence and cryptophthalmos syndrome. The
cryptophthalmos syndrome has an autosomal recessive mode of inheritance. Isolated cryptophthalmos has been reported as an
autosomal dominant trait. Prenatal diagnosis is possible using ultrasonography and fetoscopy. We report three cases of cryptophthalmos.
One with renal agenesis had cryptophthalmos syndrome and the other two had isolated cryptophthalmos or cryptophthalmos sequence. 相似文献
64.
65.
Jyotsnabaran Halder Manju Ray Subhankar Ray 《International journal of cancer. Journal international du cancer》1993,54(3):443-449
The effect of methylglyoxal (MG) on the aerobic glycolysis of Ehrlich ascites carcinoma (EAC) cells has been tested. Methylglyoxal inhibited glucose utilization and glucose 6-phosphate (G6P) and L-lactate formation in whole EAC cells. Methylglyoxal strongly inactivated glyceraldehyde 3-phosphate dehydrogenase (GA3PD) of the malignant cells, whereas MG has little inactivating effect on this enzyme from several normal sources. Methylglyoxal also inactivated only the participate hexominase of the EAC cells, but this inactivation was less pronounced than the effect on GA3PD. Methylglyoxal has little inactivating effect on glucose 6-phosphate dehydrogenase (G6PD), and no effect on L-lactate dehydrogenase (LDH) of the malignant cells. Glucose-dependent L-lactic acid formation of EAC-cell-free homogenate was strongly inhibited by MG, but when GA3PD of normal cells was added to this homogenate, significant lactate formation was observed even in the presence of MG. Methylglyoxal also inhibited the respiration of EAC-cell mitochondria. Respiration of mitochondria isolated from liver and kidney of normal mice, however, remained unaffected. As a consequence of the inhibition of glycolysis and mitochondrial respiration, the ATp level of the EAC cells was drastically reduced. Studies reported herein strongly suggest that the tumoricidal effect of MG is mediated at least in part through the inhibition of mitochondrial respiration and inactivation of GA3PD, and this enzyme may play an important role in the high glycolytic capacity of the malignant cells. 相似文献
66.
Reddy MB 《International journal for vitamin and nutrition research. Internationale Zeitschrift für Vitamin- und Ern?hrungsforschung. Journal international de vitaminologie et de nutrition》2005,75(6):405-412
While sufficient information exists on the effect of individual factors on iron absorption, their net effect in a mixed meal is less well characterized, being dependent on the combination and quantity of the factors present in the meal. Over a period of more than 25 years, several models have been developed to estimate non-heme iron bioavailability, either to assess iron absorption from a meal or iron sufficiency in populations. Initially, a model was developed to calculate iron absorption in individuals with varying iron status that included only enhancers. This model was useful in classifying the diets but has limited value for accurale assessment. Later models were modified and improved by including inhibitors in the calculations. However, some included either phytate or tea but not in combination. The models that included all the factors in calculations assumed their effect was independent and additive rather than interactive, which is an important issue in addressing iron bioavailability. Although some of the models correlated estimated bioavailability with iron status of the population, the accuracy of the estimations is of concern due to lack of quantitative measurements of bioavailability modifiers, inability to consider interactive effects, and the use of non-iron status measurements. Recent research has led to the development of refined models to assess iron bioavailability of complex meals by comprehensively taking into consideration the interactive effect among enhancers and inhibitors. However, the models are based on single-meal studies and their application to whole diets at a population level is not clear. Accurate measurements of dietary factors and independent validation are needed before using these models. To date, no single model is applicable to all diets and additional studies are needed to develop new models to predict bioavailability of whole diets accurately, in addition to addressing dietary adequacy in all populations. 相似文献
67.
Sampaio SM Panneton JM Mozes G Andrews JC Noel AA Kalra M Bower TC Cherry KJ Sullivan TM Gloviczki P 《Annals of vascular surgery》2005,19(2):178-185
Success after endovascular abdominal aortic aneurysm repair (EVAR) is dependent on device positional stability. The quest for such stability has motivated different endograft designs, and the risk factors entailed remain the subject of debate. This study aims at defining the incidence, risk factors, and clinical implications of device migration after EVAR with the AneuRx® endograft. In this study we included all consecutive 109 patients submitted to primary AneuRx placement for infrarenal aortic or aortoiliac aneurysms. Preoperative computed tomography (CT) scans were reviewed for the following anatomic characteristics: neck length, diameter, angulation, calcification, and thrombus load; and sac diameter and thrombus load. Percentage of device oversizing relative to the proximal neck diameter was determined. All postoperative CT scans were reviewed, and the distance between the lowest renal artery and the craniad end of the device was measured. A 5-mm increase in such distance was considered indicative of device migration. Migration cumulative incidence was estimated by the Kaplan-Meier method, and its association with any of the preoperative anatomical characteristics was tested using Cox proportional hazards models. Median follow-up time was 9 (range, 1-31) months. Migration occurred in nine patients, corresponding to a 15.6% estimated probability of migration at 30 months (SE=5.1%). Migration was associated with the risk of proximal type I endoleak (hazard ratio=3.39, 95% confidence interval=1.46-7.87; p=0.007). This type of endoleak occurred in three of the migration-affected patients (33.3%); all of them were resolved by additional cuff placement at the proximal landing zone. No other migration-related reinterventions were performed. The only significant associations between anatomic factors and device migration probability were the protective effects of longer necks (odds ratio [OR]=0.71 for each additional 5 mm, p=0.045) and longer overlapped portions of neck and device (OR=0.56 for each additional 5 mm, p=0.003). There was a trend toward higher probability of migration among reverse-tapered necks (OR=1.75, p=0.109). Percentage of device oversizing correlated with early neck dilation (between preoperative and first postoperative diameters, correlation coefficient=0.4, p < 0.0001), but not with late neck dilatation (between first postoperative and 1.5-year scan diameters, correlation coefficient=0.29, p=0.112). There was a trend toward higher mean percentage of late dilation among migrators (11.4%, standard error of the mean [SEM] 2.6) than nonmigrators (5.7%, SEM=1) (p=0.08), but both groups had similar mean percentages of early dilation (3%, SEM=1.6%, vs. 5.5%, SEM=0.6%; p=0.365). This result indicates that device migration is not a rare event after AneuRx implantation. This phenomenon is associated with proximal type I endoleaks. Deployment of the endograft immediately below the renal arteries might help to prevent migration, since use of greater lengths of overlapped device relative to the proximal neck has a protective effect. Migration seems to be independent of the degree of device oversizing.Presented at the 29th Annual Meeting of the Peripheral Vascular Surgery Society, Anaheim, CA, June 4-5, Sergio M. Sampaio is a recipient of the Edward S. Rogers Clinical Research Fellowship in Vascular Surgery. 相似文献
68.
Metachromatic color change induced in a suitable dye by the polyanionic chromotrope involves (i) the formation of electrostatic bonds between the dye cations and polyanions and (ii) effective aggregation of the dye cations due to their occupying the adjacent sites on the polyanion. Parallel studies are made on the effects of reagents like ethanol, dioxane and urea on the destruction of metachromasia and the binding of the dye cations on the polyanion. Conductometric titrations of chondroitin sulfate with methylene blue indicate that the dye binding on the chromotropes is less susceptible to these reagents than the metachromasia of the dye as studied spectrophotometrically. This indicates that it is not the electrostatic bond that is responsible for the metachromatic spectral shift of the dye but rather the aggregation of dye ions; and these reagents preferably attack the bonds involved in the dye-dye interaction rather than the dye-polyanion electrostatic bond. Comparison of the equivalent weights of heparin as estimated from conductometric titrations with metachromatic dyes and estimated analytically indicates that all ionic sites in heparin, unlike chondroitin sulfate, are not occupied by dye ions; this may be due to the high charge density of heparin. 相似文献
69.
Objective: To find out the magnitude of probable psychopathology in children and study association of psychopathology with demographic,
developmental and social factors.Methods: Childhood Psychopathology Measurement Schedule (CPMS) was used to measure the magnitude of probable psychopathology in 620
children from an urban slum of Miraj (Maharashtra). A second schedule recorded demographic, developmental and social factors.Results: CPMS score >10 was observed in 102 children (16.5%). It was significantly higher in children aged 7–10 years, in males,
belonging to lower socioeconomic status, large families, being first born, having low birth weight (LBW); body mass index
(BMI) less than 18.5. Low maternal education and alcohol abuse in father also had significant association with CPMS score
>10.Conclusion: Findings suggest a need to educate the community about psychological implications of LBW, large family size and overcrowding
in children. Improving maternal education and controlling alcoholism could help in reducing childhood psychopathology. 相似文献
70.