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21.
A patient had extensive congenital oral hyperpigmentation of the tongue. The clinical and histologic features set this case apart from any well-delineated disease. Clinically, the congenital onset, the appearance of large black-brownish lesions, the lack of associated systemic abnormalities, and the histologic findings of prominent deposition of melanin in the basal layer support the diagnosis of physiologic melanosis. The macular lesions of the tongue represent discrete depositions of melanin and exemplify soft tissue pigmentation of developmental origin. 相似文献
22.
J K Friel V L Naake L V Miller P V Fennessey K M Hambidge 《The American journal of clinical nutrition》1992,55(2):473-477
We measured isotopic enrichment in urine after oral and intravenous administration of stable isotopes of zinc to determine fractional absorption (FA). 68Zn and 70Zn were administered orally and intravenously to four normal adults. Subsequently, urine and fecal samples were collected for 7 and 14 d, respectively, ashed, and passed through ion-exchange columns to separate zinc from other elements. Samples were analyzed by fast-atom-bombardment mass spectrometry. From 32 h onwards the enrichment of 68Zn and 70Zn in urine declined proportionately so that FA could be determined as follows: FA = enrichment (oral/iv) x dose (iv/oral). FA determinations from urine and feces (cumulative excretion) were, respectively, for subject ZK1, urine 0.79 +/- 0.03 and feces 0.70 +/- 0.01; ZK2, 0.79 +/- 0.05 and 0.69 +/- 0.02; ZK3, 0.26 +/- 0.01 and 0.25 +/- 0.01; and ZK4, 0.41 +/- 0.02 and 0.37 +/- 0.02. ZK1 and ZK2 received the oral isotope while fasting whereas ZK3 and ZK4 received the oral isotope with meals. FA of zinc can be determined by measurement of isotope enrichment in urine. 相似文献
23.
Larry J Oesterle Sheldon M Newman W Craig Shellhart 《American journal of orthodontics and dentofacial orthopedics》2002,122(3):242-250
Light curing of composite resin material beneath orthodontic brackets is common in clinical orthodontics. Experiences with composite resins and high-intensity lights indicate some advantages to staged curing of the composite. In this study, the shear/peel bond strength of orthodontic brackets bonded to bovine enamel and cured with a pulsed xenon plasma arc light was compared with that of bonds cured with a conventional tungsten-quartz-halogen light and a nonpulsed xenon plasma arc light. The pulsed light provided less light energy than the nonpulsed lights. A small and a larger light-guide tip were used with the pulsed xenon plasma arc light. Three different orthodontic composite resin adhesives were tested with each light. The pulsed xenon plasma arc light resulted in either the same or decreased shear/peel bond strength when compared with the nonpulsed lights. There appeared to be no advantage to the use of a pulsed xenon plasma arc light in bonding orthodontic brackets. Results from using either a small or a large light-guide tip varied with the adhesive tested. 相似文献
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Ahsan Y Khan Joe Carrithers Sheldon H Preskorn Rex Lear Stephen R Wisniewski A John Rush Diane Stegman Colleen Kelley Karen Kreiner Andrew A Nierenberg Maurizio Fava 《Annals of clinical psychiatry》2006,18(2):91-98
BACKGROUND: The purpose of this paper is to use demographic and clinical data from a large diverse group of outpatients diagnosed with non-psychotic major depression to investigate the validity of the DSM-IV concept of melancholic depression. METHODS: Baseline clinical and demographic data were collected on 1500 outpatients (1456 of whom melancholia could be determined) with non-psychotic major depressive disorder (MDD) participating in the Sequenced Treatment Alternatives to Relieve Depression (STAR*D) study. Depressive symptom severity was assessed by clinical telephone interview using the 17-item Hamilton Rating Scale for Depression (HRS-D17) and the 30-item Inventory of Depressive Symptomatology (IDS-C30). The types and degrees of concurrent psychiatric symptoms were measured using a self report, the Psychiatric Diagnostic Screening Questionnaire (PDSQ), by recording the number of items relevant to each diagnostic category endorsed by study participants. RESULTS: Adjusting for severity of depression (as measured by the total HRS-D17 scores), no differences were found in the rate of melancholic depression by race, marital status, education, employment status, family history of depression, primary care versus specialty care, monthly income, and degree of psychiatric and medical co-morbidity. Melancholic depression was significantly more likely in men than women. Melancholic depression after adjustment for severity was associated with a slightly younger age at study entry, as well as with greater illness severity, and slightly shorter duration of current episode. Hispanic ethnicity was associated with lower melancholic depression rates at the .06 level of significance. CONCLUSIONS: Among outpatients with MDD, melancholic features were less likely in Hispanic patients, but more likely in slightly younger patients and in men. Melancholic features were also related to a slightly shorter current episode. These findings are consistent with the notion that external socio-demographic factors do not play an important role in the pathophysiology of melancholic depression. 相似文献
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Clinical trial registration: a statement from the International Committee of Medical Journal Editors 下载免费PDF全文
29.
An analysis of the association of trauma centers with per capita hospitalizations and death rates from injury. 总被引:1,自引:1,他引:0 下载免费PDF全文
OBJECTIVE: This study used population-based data bases to assess the association of trauma centers with per capita county hospitalization and trauma death rates in the State of North Carolina. SUMMARY BACKGROUND DATA: The current study extended previous work using two North Carolina data bases to assess the association of the presence of a trauma center with per capita county trauma death rates. METHODS: Data on per capita county trauma hospitalizations and deaths were obtained from the state hospital discharge data base and the North Carolina Medical Examiner's data base. Bivariate and multivariate analysis techniques were used. The dependent variables of interest were prehospital, hospital, and total trauma death rates and hospitalization rates for injury. RESULTS: Bivariate analysis identified a number of factors associated with per capita county hospitalizations and trauma death rates. These included the per cent unemployment, racial distribution, county alcohol tax receipts, and advanced life support certified emergency medical services providers. The per capita trauma death rates were significantly lower in counties with trauma centers compared with those without trauma centers (4.0 +/- 0.5 and 5.0 +/- 1.1 deaths per 10,000 population, p = 0.0001, respectively). The per capita hospitalizations for trauma were also lower in counties with trauma centers. Multivariate modeling showed that the presence of a trauma center and advanced life support providers were the best predictors of decreased per capita county trauma death rates. CONCLUSIONS: The study showed that the presence of a trauma center and advanced life support training were the two medical system factors that were the best predictors of the per capita county prehospital and total trauma death rates. These findings are consistent with the hypothesis that trauma centers are associated with a decrease in trauma death rates. 相似文献
30.
James G. Docherty Rosamund Carter Christopher D. Sheldon J. Stuart Falconer L. Christopher Bainbridge A. Gerard Robertson David S. Soutar 《Head & neck》1993,15(6):553-556
We examined the internal jugular veins in three groups of patients who had undergone (1) a functional neck dissection and radiotherapy, (2) a functional neck dissection alone, or (3) radiotherapy alone, using a noninvasive color Doppler ultrasound scan. The internal jugular veins were ultrasonically bilaterally normal in 18% of patients who had undergone a functional neck dissection and radiotherapy, in 88% of patients who had undergone a functional neck dissection alone, and in 57% of patients who had undergone radiotherapy alone. The combination of a functional neck dissection and radiotherapy significantly affected the internal jugular vein when compared with a functional neck dissection alone. 相似文献