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1.
The aim of this study was to assess alcoholic inpatients' smoking and coffee intake variation following withdrawal. Only moderate smokers (less than 30 cigarettes/day) showed a significant increase of cigarette consumption after alcohol withdrawal. However, their urinary cotinine level did not vary, suggesting a behavioral, and not biological, compensation through smoking following alcohol withdrawal. Heavy smokers (30 cigarettes/day or more) showed no significant clinical or biological variation of smoking behavior. Coffee consumption increased after alcohol withdrawal in all patients, irrespective of smoking habits.  相似文献   
2.
Background Processing multiple tissue sections in large Mohs cases is time consuming and labor intensive.
Objective To present innovative laboratory techniques to facilitate processing of large Mohs cases.
Methods A method for processing a large dermatofibrosarcoma protuberans Mohs case is outlined.
Results Modifications in tissue processing and equipment employed in a large Mohs case are presented.
Conclusion Innovative modifications to the standard Mohs laboratory technique can facilitate processing of large Mohs cases, resulting in high-quality, rapid frozen sections while optimizing efficiency.  相似文献   
3.
BACKGROUND: The phenomenon of wound contraction results in a decrease in wound size and a healed scar significantly smaller than the original defect. OBJECTIVE: This study was undertaken (1) to determine the amount of wound contraction in Mohs surgery defects allowed to heal by second intention, (2) to evaluate for regional differences in wound contraction based on the facial anatomic zones for second intention healing described by Zitelli, and (3) to determine whether regional differences in wound contraction account for observed differences in cosmetic outcome. METHODS: One hundred sixty secondarily healed Mohs surgery defects limited to the head and neck having a wound age of greater than 12 weeks in 102 consecutively examined patients were carefully measured with a tissue caliper. The percent wound contraction was calculated and compared for each Zitelli anatomic subunit. The final shape of the wound (quantitatively described) and the cosmetic acceptability (subjectively rated by the patient and examiner) were also compared with the percent wound contraction for each anatomic area. RESULTS: Both NEET (concave surface of the nose, eye, ear, and temple) and FAIR (forehead, antihelix, eyelids, and the remainder of the nose, lips, and cheeks) areas were identical in terms of mean wound contraction (74%), cosmetic acceptability (97%), and conversion to a wound shape with a ratio of maximal length to width of greater than 3.0 (fusiform and linear shapes) (52%). NOCH areas (convex surface of the nose, oral lips, cheeks and chin, and the helix of the ear) demonstrated less wound contraction (66%), cosmetic acceptability (78%), and fusiform-linear conversion (29%). Subset differences and variables that appear to influence wound contraction are discussed. Secondarily healed wounds in areas with one or more positive contraction variables contract 75%, whereas defects in areas with negative contraction variables contract 55%. CONCLUSIONS: Regional differences in wound contraction of secondarily healed head and neck wounds exist and account for some differences in cosmetic acceptability. Scar location, regardless of the degree of wound contraction, is the most important factor for the final cosmetic outcome.  相似文献   
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OBJECTIVE: The aim of the study was to examine the dose enhancement from scattered radiation at bone-dental implant interfaces during simulated head and neck radiotherapy. STUDY DESIGN: Four cylindrical titanium dental implants with 3 different sizes and lengths were implanted into a human mandible in 4 different positions. Ionization measurements for 6 MV X, 25 MV X, and Co-60 gamma rays were done. Thermoluminescent dosimeter (TLD 100 ) chips were used to measure radiation dose enhancement due to the scattered electrons from titanium and electronic disequilibrium at the tissue-metal interface. RESULTS: The results showed that for Co-60, there is a 21% maximum increase in dose to alveolar mandibular bone at the close proximity to the titanium. For 6-MV x-rays the dose enhancement increase was almost the same or slightly lower than for Co-60, while for 25-MV high-energy x-rays, dose enhancement was lower than that of others. This increase in dose enhancement fell off rapidly and became insignificant at 2 mm from the interface. CONCLUSION: Total dose that may lead to osteoradionecrosis risk of the mandible is slightly but not significantly affected by the scattered dose of the dental implants of lower jaw in the radiation field exposed to 3 different radiation beams.  相似文献   
6.
Ghrelin, a recently discovered peptide isolated from the gastric corpus mucosa, is believed to be important in the regulation of growth hormone secretion and has been shown to increase appetite and food intake as well. It may also have other gastrointestinal and cardiac functions. Because a cell of origin for ghrelin has not been convincingly identified in the gastric mucosa thus far, we studied the immunohistochemical expression of ghrelin in proliferative lesions of the enterochromaffin-like (ECL) cells—a cell that is not only exclusively confined to the gastric corpus mucosa but is its dominant endocrine cell type as well. Formalin-fixed, paraffin embedded tissues from three cases of gastric ECL cell hyperplasia and five ECL carcinoids (three with coexisting foci of diffuse, linear, and micronodular hyperplasia) were immunohistochemically stained for ghrelin, using a commercially available antibody. The Sevier-Munger stain for ECL cells and immunohistochemical stains for chromogranin, gastrin, serotonin, somatostatin, and vesicular monoamine transporter-2 (VMAT-2) were performed on parallel sections for correlation with the ghrelin staining results. All ECL cell carcinoids and hyperplastic lesions were positive for both the Sevier-Munger and the immunohistochemical stains for chromogranin and VMAT-2. Immunoreactivity for ghrelin was seen in 4/5 ECL carcinoids, all cases of ECL cell hyperplasia, as well as in all areas with linear and micronodular hyperplasia adjacent to the ECL cell carcinoids. In each instance, such staining was confined to the Sevier-Munger, and VMAT-2 positive cells only. Our findings indicate that the ECL cells are either the ghrelin-producing cells of the gastric mucosa or acquire the capability to synthesize ghrelin during proliferative states encompassing the entire hyperplasia to neoplasia spectrum. In view of the orexigenic and other known actions of ghrelin, the functional and/or biologic significance of ghrelin production in such ECL cell proliferations needs to be investigated further.  相似文献   
7.
PURPOSE: To assess dose rate effect on cataractogenesis in allogeneic or autologous bone marrow transplanted patients conditioned with fractionated total-body irradiation (FTBI). MATERIALS AND METHODS: Between 1987 and 2001, a total of 105 patients have received TBI conditioning for Bone Marrow Transplantation (BMT) for hematological malignancies at Gulhane Military Medical School. 12 Gy FTBI was applied in 6 fractions over 3 consecutive days with a Co60 teletherapy machine. 46 patients who have survived and were followed up after more than one year were evaluated for cataractogenesis in relation to dose rate. Conditioning therapy included only cyclophosphamide (60 mg/kg/day for two days) + TBI with no steroid and veno-occlusive disease prophylaxis. RESULTS: The median follow-up is 32 months. Posterior subcapsular cataract developed in 5 eyes of three patients out of 46 patients. The 5-year and 10-year estimated cataract incidence in the high-dose rate (> 0.04 Gy/min) group was 29% and 43% respectively while no cataracts occurred in the low-dose rate (< or = 0.04 Gy/min) group. Cataract development in the high-dose rate group versus low-dose rate group was statistically significant (p < 0.039). CONCLUSION: Cataract is a late side effect of TBI. Low-dose rate fractionated TBI is a reliable conditioning program in BMT with effective lens sparing to avoid cataractogenesis.  相似文献   
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9.
Spinocerebellar ataxia type 1 (SCA1) is an autosomal dominant neurodegenerative disorder caused by the expansion of a CAG trinucleotide repeat which encodes glutamine in the novel protein ataxin-1. In order to characterize the developmental expression pattern of SCA1 and to identify putative functional domains in ataxin-1, the murine homolog (Sca1) was isolated. Cloning and characterization of the murine Sca1 gene revealed that the gene organization is similar to that of the human gene. The murine and human ataxin-1 are highly homologous but the CAG repeat is virtually absent in the mouse sequence suggesting that the polyglutamine stretch is not essential for the normal function of ataxin-1 in mice. Cellular and developmental expression of the murine homolog was examined using RNA in situ hybridization. During cerebellar development, there is a transient burst of Sca1 expression at postnatal day 14 when the murine cerebellar cortex becomes physiologically functional. There is also marked expression of Sca1 in mesenchymal cells of the intervertebral discs during development of the spinal column. These results suggest that the normal Sca1 gene, has a role at specific stages of both cerebellar and vertebral column development.   相似文献   
10.
OBJECTIVE: To determine whether antimony may be detected in the urine during infancy and early childhood and its association with passive exposure to tobacco smoke, as assessed by urinary cotinine. DESIGN: Analysis of spare aliquots of urine collected from infants participating in studies of respiratory function and passive smoking. Urinary antimony was assayed using inductively coupled plasma mass spectroscopy in 201 urine specimens collected at different ages throughout the first two years of life from 122 term and 26 preterm infants. Urinary cotinine was measured using gas liquid chromatography. MAIN OUTCOME MEASURE: Urinary antimony concentrations. RESULTS: Absolute antimony concentrations varied widely between infants, being below the laboratory detection limit of 0.02 microgram/l in 7% of samples, below 0.5 microgram/l in 90.5%, and above the reference value of 1 microgram/l reported for non-occupationally exposed UK populations in 4%. Creatinine standardised antimony values were unrelated to postnatal age or urinary cotinine concentrations and were highest in urine collected from preterm infants within 24 hours of birth (geometric mean (95% confidence interval): 2.3 ng/mg (1.5 to 3.4)). CONCLUSIONS: Although antimony is present at very low concentrations in urine during infancy and early childhood, the relevance to health is uncertain. The higher levels found in preterm infants may reflect prematurity or fetal assimilation of antimony. Tobacco is unlikely to be an important source of environmental exposure to antimony during infancy and early childhood.  相似文献   
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