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81.
The National Radiological Protection Board (NRPB) has recommended the introduction of dose-width product (DWP) for the measurement of patient dose in panoramic dental radiology and has proposed a reference level of 65 mGy mm for adult exposures. This paper describes a method for measuring DWP and dose-area product (DAP) using thermoluminescent dosemeters (TLDs). The technique was used on 16 sets with a range of exposure settings. The mean value of DWP was 14% higher than the mean value reported from a survey by the NRPB. This difference is most likely to be caused by systematic variations due to measurement method. The average DAP for a standard adult examination was shown to be 11.3 cGy cm2. Data are presented so that the DAP can be derived from the exposure factors (tube current and operating potential) and beam area. Based on published data for effective dose, it is estimated that the DAP to effective dose conversion factor is approximately 0.06 mSv(Gy cm2)-1. The average DAP value (11.3 cGy cm2) can be compared with the average value for intraoral radiography (9.3 cGy cm2) based on the NRPB survey of entrance surface doses assuming 6 cm circular collimation. 相似文献
82.
A Smith J Egan G Ridley E Haan P Montgomery K Williams E Elliott 《Archives of disease in childhood》2003,88(3):263-264
This is the first population based study to estimate the birth prevalence of DNA proven Prader-Willi syndrome. Thirty infants were reported to the Australian Paediatric Surveillance Unit between 1998 and 2000, a prevalence of 4 per 100,000 live births or approximately 1/25,000 live births per annum. 相似文献
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Malcolm S Reid Burt Angrist Sherryl A Baker Siobhan O'leary Jennifer Stone Marion Schwartz Deborah Leiderman Ann Montgomery Ahmed Elkashef Dorota Majewska James Robinson John Rotrosen 《Substance Abuse》2005,26(2):5-14
A placebo controlled, double-blind trial of mecamylamine treatment of cocaine dependence was performed in methadone or LAAM maintained subjects who met DSM-IV criteria for cocaine dependence. After an eight-week placebo run-in screening period, 35 subjects were randomly assigned to receive either mecamylamine (6 mg/day) or placebo transdermal patches for a 16-week treatment period. Outcome measures included quantitative urine benzoylecognine (BE) levels, self-report of cocaine use, cocaine craving, global impression scores, mood, retention, and safety. Mecamylamine was well tolerated, and study retention did not differ by treatment group. Evidence for cocaine use, based on urine BE levels and cocaine abstinence rates, did not differ by treatment group. Self reported cocaine use, cocaine craving, and global impression scores showed moderate improvement in both groups, with a significantly greater reduction in cocaine craving (p < 0.05) and self-rated severity of cocaine dependence (p < 0.05) in the placebo group. This pilot study does not support the effectiveness of mecamylamine for the treatment of cocaine dependence in methadone or LAAM maintained patients. 相似文献
87.
Jazlyn Read Judith Symmons Jane M. Palmer Grant W. Montgomery Nicholas G. Martin Nicholas K. Hayward 《Familial cancer》2016,15(4):651-663
Familial cancer risk has been proposed as a shared feature of many cancers, and overall susceptibility is influenced by combinations of low to moderate risk polymorphisms, rare high penetrance germline mutations, and modulation of risk by environmental and genetic factors. Clustering of melanoma occurs in approximately 10 % of families, and an over-representation of additional cancers has been noticed in some ‘melanoma’ families. The degree to which other cancers aggregate in families affected by melanoma has not been well defined. Therefore, this study aimed to assess the risk of cancers other than melanoma in a cohort of 178 ‘intermediate risk’ melanoma families, not selected for specific genetic mutations. Families designated as ‘intermediate risk’ had two first degree relatives (FDRs) affected by melanoma when ascertained between 1982 and 1990, and were followed up over a 33 year period to assess new occurrences of cancer. We included 414 melanoma cases and 529 FDRs, comprising 25,264 person years of observation. Standardised incidence ratios and their 95 % confidence intervals were calculated for all invasive cancers, comparing observed to expected cases of cancer based on age and sex specific incidence rates for the Queensland population. Statistically significant increases were found for bladder cancer in females (observed, 7; expected, 1.99; SIR, 3.52; 95 % CI 1.41–7.25), lymphoid leukaemia in females (observed, 6; expected, 1.75; SIR, 3.43; 95 % CI 1.26–7.46), and myeloma in female melanoma cases (observed, 4; expected, 0.82; SIR, 4.89; 95 % CI 1.33–12.52). Over-representation of bladder cancer, lymphoid leukaemia, and myeloma in females of the cohort may suggest sex-dependent co-modifiers, and it is possible that specific combinations of polymorphisms predispose to certain cancer types. 相似文献
88.
Phyllis Montgomery Karen McCauley Patricia Hill Bailey 《Issues in mental health nursing》2013,34(10):624-630
This article presents a discourse analysis of a woman's written account of mental illness and homelessness. In her preparation as a co-presenter at a conference for decision- and policy-makers, Anna wrote eight distinct drafts of her speaking notes; each time emphasizing different aspects of her experiences with mental illness and homelessness. By sharing her preparatory writings, Anna offers a rare insight into the ‘evolution’ of the thinking that went into representing her story to an audience of professionals. In addition, this analysis represents an interpretation and alternative forum to learn from Anna's story. 相似文献
89.
Phyllis Montgomery Sharolyn Mossey Sara Adams Patricia H. Bailey 《International journal of mental health nursing》2012,21(6):524-532
Living through postpartum depression (PPD) might lead women to seek a variety of support to re‐establish their well‐being, including a hybrid of traditional and non‐traditional services. Within this mix, some women participate in peer groups; however, there is a paucity of research regarding their subjective experiences of engaging in this type of support. The purpose of this study was to describe how women talked about living through PPD in the context of a peer support group. This focused ethnography was a component of a larger participatory action study in northern Ontario, Canada. The seven members of a 5‐week peer support group described their postpartum experiences through written, visual, and spoken stories. Using structural narrative analysis, stories about recovery were identified across the data. Three groups of recovery stories were labelled as illness, mothering wisdom, and mobilizing. The findings suggested that women actively sought and established a therapeutic space for PPD recovery with peers. As such, health‐care providers are encouraged to acknowledge the merits and advocate for the multiple and diverse alliances women might require to actualize recovery. 相似文献
90.
Jamal A. Ahmed Edna Moturi Paul Spiegel Marian Schilperoord Wagacha Burton Nailah H. Kassim Abdinoor Mohamed Melvin Ochieng Leonard Nderitu Carlos Navarro-Colorado Heather Burke Susan Cookson Thomas Handzel Lilian W. Waiboci Joel M. Montgomery Eyasu Teshale Nina Marano 《Emerging infectious diseases》2013,19(6):1010-1011