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41.
Background: Recent studies have shown a substantial decline in caries experience in Australian Army recruits between 1996 and 2002–2003, and in Australian adults between 1987–1988 and 2004–2006. However, studies in children have reported an increasing trend in caries experience between 1998 and 2002. The aim of this study was to investigate caries experience in Australian Army recruits in 2008. Methods: A cross‐sectional study involving 1084 Australian Army recruits was conducted from January to May 2008. Data were obtained from a clinical dental examination with bitewing radiographs, and a questionnaire elicited socio‐demographic data and history on lifetime exposure to fluoridated drinking water. Results: Mean DMFT scores were 3.16, 4.08, 5.16 and 7.11 for recruits aged 17–20, 21–25, 26–30 and 31–35 years, respectively. Recruits with a lifetime exposure to fluoridated drinking water had a mean DMFT of 3.02, while recruits with no exposure had a mean DMFT of 3.87. Conclusions: Caries experience in Australian Army recruits aged 17–25 years increased between 2002–2003 and 2008. Recruits with lifetime exposure to fluoridated drinking water had 25 per cent less caries experience compared with recruits who had no exposure to fluoridated drinking water after adjusting for the effects of age, gender, education and socio‐economic status. 相似文献
42.
It has been reported that chloroform administered to BDF1 mice by
inhalation for 2 years at concentrations of 5, 30 or 90 p.p.m. for 6 h/day,
5 days/week induced an increase in renal cell tumors in male but not female
mice exposed to the doses of 30 and 90 p.p.m. A small increase in liver
tumors was statistically significant in the female mice at 90 p.p.m. if the
incidences of carcinomas and adenomas were combined. Because chloroform is
not a DNA reactive mutagen, a 13-week time-course and dose-response study
was conducted under conditions of the original bioassay to examine whether
regenerative cell proliferation was an underlying mechanism of
carcinogenesis. Mice were given bromodeoxyuridine via infusion during the
last 3.5 days prior to necropsy to label cells in S-phase. Chloroform
induced pathology and regenerative cell proliferation, measured as the
labeling index (LI, percentage of cells in S-phase), were assessed
microscopically and immunohistochemically. Male mice exposed to 30 and 90
p.p.m. exhibited a dose-dependent increase in regenerating tubules within
the renal cortex and up to a 31-fold increase in LI. No renal lesions or
increased LI were observed in females. Increased centrilobular to midzonal
hepatocyte degeneration and vacuolation and a 7-fold increase over controls
in the hepatocyte LI were observed in the female mice at 90 p.p.m. at 13
weeks. Males exhibited similar pathology, but the increase in LI was not
sustained. The observed correlations between cytolethality and regenerative
cell proliferation with tumor formation supports extensive evidence that
chloroform induces cancer via a non- genotoxic-cytotoxic mode of action. A
concentration of 5 p.p.m. is the no-observed-adverse-effect level for
nephrotoxicity, cell proliferation and cancer. An appropriate safety factor
applied to this value is a straightforward approach to cancer risk
assessment that is consistent with the mode of action of chloroform.
相似文献
43.
MV Merrick A Notghi N Chalmers AG Wilkinson WS Uttley 《Archives of disease in childhood》1995,72(5):388-392
In 3646 children with at least one confirmed urinary tract infection the prevalence of vesicoureteric reflux at presentation was correlated with progressive renal damage during follow up of not less than two and up to 16 years. Reflux was not demonstrated either at presentation or at any subsequent time in almost one half of the children who suffered progressive renal damage and was not a risk factor for progressive renal damage in boys under 1 year. It was an important risk factor in boys over 1 year and in girls of any age. The risk of progressive renal damage in children in whom micturating cystourethrography (MCU) did not reveal vesicoureteric reflux was substantially greater than in those who indirect isotope voiding study (IVS) did not show reflux. The risk of deterioration for those in whom reflux was demonstrated was similar for both techniques. This discrepancy indicates an appreciably higher false negative rate for the MCU than the IVS. Dilatation of the renal pelvis detected by ultrasound was associated with a significantly increased risk of progressive damage only when associated with reflux, but most children with progressive damage did not have a dilated collecting system at presentation. 相似文献
44.
45.
Organization, expression and polymorphism of the human persyn gene 总被引:13,自引:0,他引:13
Ninkina NN; Alimova-Kost MV; Paterson JW; Delaney L; Cohen BB; Imreh S; Gnuchev NV; Davies AM; Buchman VL 《Human molecular genetics》1998,7(9):1417-1424
Persyn is a recently identified member of the synuclein family with a
distinct pattern of expression during pre- and postnatal development of the
mouse peripheral and central nervous systems. As with other synucleins,
persyn is believed to be involved in the pathogenesis of human
neurodegenerative diseases. However, in contrast to other synucleins, high
levels of persyn mRNA expression were also found in advanced breast
carcinomas, suggesting an involvement of the encoded protein in breast
tumour progression. Here we have used an antibody specific to human persyn
to demonstrate that the level of this protein is increased in ageing
cerebral cortex and in breast tumours. We cloned, characterized and
sequenced the human persyn genomic locus and localized it to the long arm
of chromosome 10 in the q23.2-q23.3 region. Sequence information was used
to search for specific mutations in the protein coding regions of persyn
mRNA and the persyn gene in breast tumours and tumour cell lines. No
tumour-specific mutations were found, but two linked polymorphisms in the
coding region were detected, both in mRNA and exons III and IV of the gene.
These results suggest that development of breast tumours correlates with
overexpression of the wild-type persyn protein. Detailed characterization
of the human persyn locus is important for further studies of the
involvement of persyn in neurodegeneration and malignancy.
相似文献
46.
47.
48.
Simulated pulmonary nodules: detection with dual-energy digital versus conventional radiography 总被引:9,自引:0,他引:9
Niklason LT; Hickey NM; Chakraborty DP; Sabbagh EA; Yester MV; Fraser RG; Barnes GT 《Radiology》1986,160(3):589-593
Performance of a prototype dual-energy digital chest radiography unit in detecting calcified and noncalcified simulated pulmonary nodules was compared with that of a highly optimized, conventional system. Nodules ranging in size (0.5, 1.0, and 1.6 cm), in number (five to 11), and in calcium content (0-25 mg) were superimposed over the lungs of a frozen, unembalmed, human chest phantom. For each technique, six observers examined 50 posteroanterior projections with different randomized nodule locations. Detection consisted of locating and assigning a level of confidence to each perceived nodular opacity. The resulting plots of the true-positive fraction versus the mean number of false-positive calls per projection indicate that for both calcified and noncalcified nodules, the digital unit performed significantly better (P less than .01). 相似文献
49.
Anja?C?Waselau Daniel?Nadler Jessika?MV?Müller Katalin?Zlinszky Monika?Hilbe J?rg?A?Auer Brigitte?von RechenbergEmail author 《BMC musculoskeletal disorders》2005,6(1):60
Background
Differences in overall performance of osteochondral photooxidized grafts were studied in accordance of their species origin and a new, more rigorous cleansing procedure using alcohol during preparation. 相似文献50.
J Vega Gutiérrez † A Miranda Romero † G Martínez ‡ MV Torrero † M López de Juan§ 《Journal of the European Academy of Dermatology and Venereology》2003,17(3):324-327
The Laugier-Hunziker syndrome is an acquired, idiopathic, benign mucocutaneous hypermelanosis that usually occurs on the lips and oral mucosa, although it may appear at other sites. Nails are frequently involved, mainly forming longitudinal hyperpigmented bands. We report the case of a patient that presented a typical picture of this entity, nearly 1 year after the beginning of treatment with levodopa. Two years after the first lesions occurred, she developed Addison's disease. The patient suffered from a diffuse discrete hyperpigmentation (it was more remarkable on exposed areas) and an intensification of the melanotic macules that were previously noticeable before in oral and genital mucosa, fingers, toes and nails. Hormonal replacement treatment enabled the control of laboratory and general manifestations and to decrease the degree of mucocutaneous hyperpigmentation considerably, despite initial hyperpigmented lesions persisting in described areas. 相似文献