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71.
BACKGROUND: The proportion of Australian adults achieving physical activity levels believed to be sufficient for colon cancer prevention was estimated, and sociodemographic correlates (age, gender, educational attainment, occupation, marital status, and children in household) of meeting these levels of activity were analyzed. METHODS: Data from the 2000 National Physical Activity Survey were used to estimate the prevalence of participation in physical activity in relation to three criteria: generic public health recommendations, weekly amount of at least moderate-intensity physical activity currently believed to reduce risk of colon cancer, and weekly amount of vigorous-intensity physical activity believed to reduce risk of colon cancer. RESULTS: Overall, 46% of adults met the generic public health criterion, 26% met the colon cancer criterion based on participation in at least moderate-intensity physical activity, and 10% met the colon cancer criterion based on vigorous-intensity physical activity. Women were less likely than men to meet the colon cancer criteria. Younger and more educated persons were more likely to meet all three criteria. The most pronounced differences between gender, age, and educational attainment groups were found for meeting the amount of vigorous-intensity physical activity believed to reduce risk of colon cancer. CONCLUSIONS: The population prevalence for meeting proposed physical activity criteria for colon cancer prevention is low and much lower than that related to the more generic public health recommendations. If further epidemiologic studies confirm that high volumes and intensities of activity are required, the public health challenges for colon cancer will be significant.  相似文献   
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Research in translational medicine often requires high-resolution characterization techniques to visualize or quantify the fluorescent probes. For example, drug delivery systems contain fluorescent molecules enabling in vitro and in vivo tracing to determine biodistribution or plasma disappearance. Albeit fluorescence imaging systems with sufficient resolution exist, the sample preparation is typically too complex to image a whole organism of the size of a mouse. This article established a mesoscopic imaging technique utilizing a commercially available cryo-microtome and an in-house built episcopic imaging add-on to perform imaging during serial sectioning. Here we demonstrate that our automated red, green, blue (RGB) and fluorescence mesoscope can generate sequential block-face and 3-dimensional anatomical images at variable thickness with high quality of 6 µm × 6 µm pixel size. In addition, this mesoscope features a numerical aperture of 0.10 and a field-of-view of up to 21.6 mm × 27 mm × 25 mm (width, height, depth).  相似文献   
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The aim of this study was to compare the efficacy of two embryo transfer catheters: Wallace and Rocket Embryon in an IVF programme of a tertiary referral university centre. A total of 308 patients undergoing embryo transfer were prospectively randomized to either a transfer with the Wallace catheter or a transfer with the Rocket catheter. The main outcome measure in this study was the clinical pregnancy rate, and secondary outcome measures included implantation rate, visibility of the catheter under ultrasound, number of retained embryos post transfer, and whether change of catheter was required. In addition, patient discomfort during the procedure was recorded. Pregnancy and implantation rates were similar when Wallace or Rocket catheters were used. However, for the Rocket catheter, the tip was more often clearly seen on ultrasound and it had a lower rate of retained embryos in the catheter after transfer (P < 0.05). Experience with different transfer catheters is recommended for difficult cases.  相似文献   
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OBJECTIVES: To estimate the type-specific seroprevalence and identify the risk factors associated with herpes simplex virus (HSV)-2 infection in pregnant women in Bucharest, Romania. METHODS: A prospective survey was conducted in 452 subjects, aged 15-39 years, at the Elias Hospital, during the years 2004-2005. We evaluated serum IgG anti-bodies to HSV-1 and HSV-2 using the HerpeSelect ELISA test. All subjects completed an epidemiological questionnaire. RESULTS: Seroprevalence was 87.3% and 15.1% for HSV-1 and HSV-2, respectively. The risk factors for HSV-2 infection were lower level of education and a greater number of sexual partners. Elementary school and high-school graduates were 6.28 and 2.26 times more exposed than University graduates. Having 2-3 partners and more than three partners was associated with 2.43 and 4.26 times the risk of acquiring HSV-2, compared with having one partner. CONCLUSIONS: In pregnant women, HSV-1 seroprevalence was higher than in Western Europe but similar to that in Eastern Europe. HSV-2 seroprevalence was within European ranges. Both were lower than in the USA. Risk factors for HSV-2 infection may lead to prevention programs.  相似文献   
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Juvenile granulosa cell tumor (JGCT) of testis is extremely rare in childhood. It is considered a benign entity because metastasis has never been reported. Testicular-sparing surgery is the recommended treatment. We reported this case in a newborn who presented with unilateral scrotal swelling. Histopathology and immunohistochemistry confirmed JGCT. Follow-up at 6 months after surgery did not show any recurrence. Even though JGCT is very rare in childhood, it is one of the important differentials of newborn scrotal mass.  相似文献   
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1. Type-specific antipneumococcus immunity has been induced in rabbits by immunization with antigen prepared by combining a specific derivative of the capsular polysaccharide of Type III Pneumococcus with globulin from horse serum. 2. Rabbits immunized with this antigen acquire active immunity against infection with virulent Type III pneumococci. 3. The sera of the immune rabbits contain type-specific antibodies which precipitate the Type III capsular polysaccharide, agglutinate Type III pneumococci, and specifically protect mice against Type III infection. 4. The experimental data are discussed with reference to: (1) the concurrence in the immune sera of type-specific antibodies for Pneumococcus and precipitins for horse globulin; (2) the determining influence of the capsular polysaccharide on the specificity of the antigen as a whole; (3) the unity of the type-specific precipitins, agglutinins, and protective antibodies induced by a single compo of the pneu mococcus in chemical union with an unrelated, animal protein.  相似文献   
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BackgroundMeningiomas are the most common primary intracranial tumor in adults. Clinical care is currently guided by the World Health Organization (WHO) grade assigned to meningiomas, a 3-tiered grading system based on histopathology features, as well as extent of surgical resection. Clinical behavior, however, often fails to conform to the WHO grade. Additional prognostic information is needed to optimize patient management.MethodsWe evaluated whether chromosomal copy-number data improved prediction of time-to-recurrence for patients with meningioma who were treated with surgery, relative to the WHO schema. The models were developed using Cox proportional hazards, random survival forest, and gradient boosting in a discovery cohort of 527 meningioma patients and validated in 2 independent cohorts of 172 meningioma patients characterized by orthogonal genomic platforms.ResultsWe developed a 3-tiered grading scheme (Integrated Grades 1-3), which incorporated mitotic count and loss of chromosome 1p, 3p, 4, 6, 10, 14q, 18, 19, or CDKN2A. 32% of meningiomas reclassified to either a lower-risk or higher-risk Integrated Grade compared to their assigned WHO grade. The Integrated Grade more accurately identified meningioma patients at risk for recurrence, relative to the WHO grade, as determined by time-dependent area under the curve, average precision, and the Brier score.ConclusionWe propose a molecularly integrated grading scheme for meningiomas that significantly improves upon the current WHO grading system in prediction of progression-free survival. This framework can be broadly adopted by clinicians with relative ease using widely available genomic technologies and presents an advance in the care of meningioma patients.  相似文献   
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