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111.

Background

Chlamydia trachomatis is a common sexually transmitted infection in Australia. This report aims to measure the burden of chlamydia infection by systematically reviewing reports on prevalence in Australian populations.

Methods

Electronic databases and conference websites were searched from 1997?C2011 using the terms ??Chlamydia trachomatis?? OR ??chlamydia?? AND ??prevalence?? OR ??epidemiology?? AND ??Australia??. Reference lists were checked and researchers contacted for additional literature. Studies were categorised by setting and participants, and meta-analysis conducted to determine pooled prevalence estimates for each category.

Results

Seventy-six studies met the inclusion criteria for the review. There was a high level of heterogeneity between studies; however, there was a trend towards higher chlamydia prevalence in younger populations, Indigenous Australians, and those attending sexual health centres. In community or general practice settings, pooled prevalence for women <25?years in studies conducted post-2005 was 5.0% (95% CI: 3.1, 6.9; five studies), and for men <30?years over the entire review period was 3.9% (95% CI: 2.7, 5.1; six studies). For young Australians aged <25?years attending sexual health, family planning or youth clinics, estimated prevalence was 6.2% (95% CI: 5.1, 7.4; 10 studies) for women and 10.2% (95% CI: 9.5, 10.9; five studies) for men. Other key findings include pooled prevalence estimates of 22.1% (95% CI: 19.0, 25.3; three studies) for Indigenous women <25?years, 14.6% (95% CI: 11.5, 17.8; three studies) for Indigenous men <25?years, and 5.6% (95% CI: 4.8, 6.3; 11 studies) for rectal infection in men who have sex with men. Several studies failed to report basic demographic details such as sex and age, and were therefore excluded from the analysis.

Conclusions

Chlamydia trachomatis infections are a significant health burden in Australia; however, accurate estimation of chlamydia prevalence in Australian sub-populations is limited by heterogeneity within surveyed populations, and variations in sampling methodologies and data reporting. There is a need for more large, population-based studies and prospective cohort studies to compliment mandatory notification data.  相似文献   
112.

Background

The use of the flexible endoscope as a surgical platform potentially exposes a range of new surgical approaches and benefits yet to be fully defined. A new method using the flexible endoscope to undertake axillary dissection for breast cancer treatment is explored together with an investigation into its acceptability to the general public.

Methods

Endoscopic axillary dissection via a transumbilical approach using the flexible endoscope passed subcutaneously from the umbilicus is described for four human cadaveric axillas. A questionnaire, validated by clinicians, explored the general public’s reaction to the approach and how it might be influenced by potentially serious morbidity such as an increased rate of cancer recurrence.

Results

All axillas were accessed successfully via the transumbilical approach. Levels 1 and 2 axillary dissection was attempted on four axillas. Scarring from previous axillary surgery prevented dissection in one case. In the remaining three cases, respectively 12, 11, and 14 lymph nodes were harvested. The operative times improved with each case, from 1080 to 390 min. A total of 127 people responded to the questionnaire, with 73 % preferring the described approach over the open and periareolar alternatives when morbidities were considered equivalent. When a hypothetical elevated risk of cancer recurrence was included with the transumbilical approach, one-fifth of the public still accepted the approach due to the likelihood of a superior cosmesis.

Conclusion

The use of the flexible endoscope for oncologically safe levels 1 and 2 axillary dissection is possible and would be acceptable to the general public if it were clinically approved. However, significant challenges with the current endoscopic equipment and relevant instrumentation limit the potential of the technique. Technical innovation in terms of new instrument design with improved ergonomics will reduce long operating times and fatigue, thus ensuring surgical acceptance of the flexible endoscope.  相似文献   
113.
This study assesses whether sense of coherence (SOC) predicts incidence of tooth decay over 4 years and the role of dental behaviours in explaining the effect of SOC on incidence of tooth decay. Data from 994 adults who participated in both the Health 2000 survey and the Follow-Up Study of Finnish Adults' Oral Health were analysed for this study. At baseline, participants provided information on demographic characteristics, education level, the SOC scale and dental behaviours (tooth brushing frequency, dental attendance and sugar intake frequency). The 4-year incidence of tooth decay was calculated using data from baseline and follow-up clinical oral examinations. Baseline SOC was significantly related to 4-year incidence of tooth decay after adjustment for demographic factors and education (relative risk: 0.79, 95% CI: 0.63-0.98). This effect was fully attenuated after further adjustment for the three dental behaviours. Tooth brushing frequency and dental attendance were the only dental behaviours significantly related to incidence of tooth decay. This prospective study suggests that SOC predicts incidence of tooth decay and that dental behaviours may help explaining why adults with strong SOC have lower risk of developing tooth decay than those with weak SOC.  相似文献   
114.
The flow patterns of a prosthetic heart valve in the aortic or mitral position can change according to its type and orientation. This work describes the use of 2D particle image velocimetry (PIV) applied to the in vitro flow fields characterization inside the upper part of a left ventricular model at various heart rates and as a function of two orientations of stented tricuspid mitral bioprostheses. In the ventricular model, each mitral bioprosthesis (27 and 31 mm diameter) was installed in two orientations, rotated by 180°, while the aortic bileaflet mechanical valve (27 mm diameter) remained in a fixed orientation. The results (N = 50) showed changes in the intraventricular flow fields according to the mitral bioprostheses positioning. Also, changes in the aortic upstream velocity profiles were noticed as a function of mitral orientations.  相似文献   
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This article provides answers to many questions medical students ask about the specialty of family medicine. It was developed through the collaborative efforts of several family medicine organizations, including the American Academy of Family Physicians, the Society of Teachers of Family Medicine, the Association of Family Medicine Residency Directors, and the Association of Departments of Family Medicine. The article discusses the benefits of primary care and family medicine, the education and training of family physicians, the scope of medical practice in the specialty, and issues related to lifestyle and medical student debt.  相似文献   
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The dynamic hip screw (DHS) consists of a barrel-plate fixed to the relatively-straight proximal femoral shaft, and a screw which slides within the barrel at a fixed angle, usually 135°. The guide-wire is inserted using a guide at the set angle. Guide design varies between manufacturers, with some new guides being particularly short. We analysed the impact of guide design on the resulting trajectory of the guidewire, and its potential to cause a surgical error. Twenty AP hip radiographs were analysed. Trauma Cad (Brainlab, Munich, Germany) software was used to template a 4-hole 135° DHS onto the intact femur with the screw positioned in the center of the head. A template of a Stryker (Michigan, USA) 135° DHS guide (37 mm long) was then overlaid at the hip screw entry point, and the set trajectory marked. The divergence between the two trajectories was measured (α angle). The distance the guide would have to be moved inferiorly to attain the correct position in the head was then noted. The median divergence (α angle) caused by the guide relative to the ideal position was 6° (range 2–12). This led to the guidewire placement being a median of 9.1 mm (range 3–23) superior in the head (β).To achieve the correct position of the wire in the head, the guide needed to be moved inferiorly a median of 8 mm (range 2–10). © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:574–577, 2020  相似文献   
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