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Our objective was to examine patterns of withholding/withdrawal (WH/WD) of life support in trauma patients and to determine whether WD/WH of life support is used more frequently in elderly patients. This is a retrospective cohort study of injured elderly (> or = 65 years) and young patients (< 65 years) from 1994 through 1998 treated at a surgical intensive care unit in a community tertiary-care hospital. We studied the cases of 82 patients (30 elderly and 52 young patients) with WH/WD of life support after injury. Our main outcome measures were demographic and clinical characteristics of elderly and young patients undergoing WH/WD of life support after injury with an association between age and WH/WD of life support. Of 102 total trauma patient deaths 82 had WH/WD of life support. This mode was chosen in 52 (80%) patients under the age of 65 and in 30 (81%) patients age 65 or greater. Patients in the younger cohort had a higher mean Injury Severity Score and Abbreviated Injury Score of 5 (P < 0.05). The elderly cohort had a higher incidence of pre-existing disease (< 0.001). Length of stay was similar between the populations. We conclude that the elderly were no more likely to have WH/WD of life support than were younger patients. However, the older patients were less severely injured as measured by Injury Severity Score and percentage with Abbreviated Injury Score head of 5. Other factors such as the presence of pre-existing disease may influence the decision to withhold or withdraw life support to a greater degree than the actual severity of injuries.  相似文献   
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Abstract:  The purpose of this study was to assess the predictive value of smoking history on breast cancer diagnosis in a referral clinic population. We conducted a case–control study using clinical data collected on 8,097 female patients (1,225 breast cancer cases and 6,872 controls) seen in the Mayo Clinic Breast Clinic between August 1, 1993 and November 31, 2003. Breast cancer patients and noncancer patients significantly differed with respect to age at time of the index visit (p < 0.001), number of pregnancies (p = 0.006), number of live births (p = 0.002), vital status at last known follow-up (p < 0.001), current menstruation (p < 0.001), age at menopause (p < 0.001), history of hysterectomy (p < 0.001), use of oral contraception (p = 0.05), duration of oral contraception use (p = 0.001), use of other exogenous hormones (p < 0.001), duration of exogenous hormone use (p = 0.05), breast pain at time of index visit (p = 0.002), smoking status (p < 0.001), and use of five or more alcoholic beverages per week (p = 0.002). After adjustment for these baseline characteristics, having a personal history of smoking was found to be predictive of breast cancer diagnosis (odds ratios [OR] = 1.25, p = 0.004). Other positive predictors for breast cancer diagnosis were: age (OR = 1.02, p < 0.001), history of hysterectomy (OR = 0.66, p < 0.001), prior use of oral contraception for more than 11 years (OR = 2.10, p < 0.001), and prior use of other exogenous hormones/estrogen (OR = 1.81, p < 0.001). In this referral practice having a personal history of smoking is predictive of breast cancer diagnosis. Further studies are needed to further explore this relationship.  相似文献   
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We report on two patients with granular cell atypical fibroxanthoma. Both neoplasms were solitary, light-tan, dome-shaped papules on sun-exposed areas of the head in two elderly white men. Microscopically, these neoplasms showed a dermal proliferation of pleomorphic granular cells with irregular hyperchromatic nuclei, multinucleated cells, and scattered mitoses. Immunohistochemical stains were positive for CD68 and vimentin and negative for Melan-A or human melanoma black (HMB)-45, S-100 protein, pancytokeratin, and actin, consistent with atypical fibroxanthoma. The differential diagnosis of granular cells in neoplasms containing cytological pleomorphism is challenging in view of the many different neoplasms that may present with granular cytoplasm. These include the conventional granular cell tumor and its malignant form, leiomyoma, leiomyosarcoma, dermatofibroma, dermatofibrosarcoma protuberans, and angiosarcoma.  相似文献   
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Two patients with eccrine syringofibroadenomas were studied. The first patient had a 3-year history of asymptomatic, unilateral, linear, moist mosaic plaques of the lower part of the left leg and foot; the second patient had a solitary papule on the back. Histologically, both tumors exhibited superficial elongated strands of eccrine ductal epithelium containing occasional lumina lined by an eosinophilic cuticle. The stroma was loose, myxoid, and fibrovascular. The secretory portions of the eccrine glands were ectatic in the first patient but were not seen in the second patient. We believe these lesions represent acrosyringeal hamartomas (nevi), although some authors interpret them as adenomas. The literature seems to indicate that lesions with similar histologic features may be solitary, multiple, or combined with other neoplasms; in other cases, the lesions may possibly represent an unusual morphologic expression of hidrotic ectodermal dysplasia.  相似文献   
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UltraSeal XT® hydro? is a new hydrophilic, light-cured, methacrylate-based pit and fissure sealant which has been developed by Ultradent Products, USA. The sealant is highly filled with a 53 wt.% mixture of inorganic particles which confer both thixotropy and radiopacity. The principal purpose of this study was to investigate the microleakage of UltraSeal XT® hydro? as a function of different enamel etching techniques. The occlusal surfaces of sound, extracted human molars were either acid etched, Er:YAG laser irradiated or successively laser irradiated and acid etched. UltraSeal XT® hydro? was applied to each group of teeth (n?=?10) which were subjected to a thermocycling process consisting of 2500 cycles between 5 and 50 °C with a dwell time of 30 s. Microleakage assessments were then carried out using 0.5 % fuchsin dye and optical microscopy. The microleakage score data were analysed using the Kruskal-Wallis, Mann–Whitney U test with Bonferroni adjustment. No significant differences in microleakage were noted between the individually acid etched and laser-irradiated groups (p?>?0.05); however, teeth treated with a combination of laser irradiation and acid etching demonstrated significantly lower microleakage scores (p?<?0.001). Electron microscopy with energy-dispersive X-ray analysis revealed that the mineral filler component of UltraSeal XT® hydro? essentially comprises micrometre-sized particles of inorganic silicon-, aluminium- and barium-bearing phases. Laser etching increases the roughness of the enamel surface which causes a concentrated zoning of the filler particles at the enamel-sealant interface.  相似文献   
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