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61.
To tackle unhealthy eating among adolescents, it is crucial to understand the dietary knowledge, attitudes, and practices (KAP) on which adolescent eating habits are based. This qualitative study identifies the gaps in KAP by exploring what Chinese adolescents know, perceive, and practice regarding healthy eating to better inform targeted interventions for this important health problem. Parent–adolescent dyads were purposively sampled based on, for example, the dietary intake, age, and gender of the adolescent and household income, and each completed a 30 to 60 min interview. Twelve themes were synthesized: knowledge: (1) dietary recommendations, (2) health outcomes of healthy eating, (3) nutrition content in food, and (4) access to healthy meals; attitudes: (5) outcome expectation for healthy eating, (6) food preferences, and (7) self-efficacy regarding adopting healthy eating; and practices: (8) going grocery shopping for healthy food, (9) eating home-prepared meals. (10) eating out in restaurants or consuming takeaway food, (11) fruit and vegetable consumption, and (12) snacking, perceived unhealthy eating to be low risk, made unhealthy choices regarding snacking and eating out, and had insufficient fruit and vegetable intake. Programs should emphasize the positive short-term health outcomes of healthy eating and empower adolescents to acquire food preparation skills to sustain healthy eating habits.  相似文献   
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Dietary interventions may have the potential to counter age-related cognitive decline. Studies have demonstrated an improvement in age-related cognitive impairment in animals after supplementation with plant extracts containing flavonoids but there are few human studies. This double-blind, controlled study examined the effects on cognitive performance of a 5 week supplementation with Enzogenol Pinus radiata bark extract containing flavonoids, in 42 males aged 50-65 years, with a body mass index >25. Participants were supplemented for 5 weeks either with Enzogenol plus vitamin C, or with vitamin C only. A battery of computerized cognitive tests was administered, and cardiovascular and haematological parameters were assessed prior to and following supplementation. The speed of response for the spatial working memory and immediate recognition tasks improved after supplementation with Enzogenol plus vitamin C, whereas vitamin C alone showed no improvements. A trend in a reduction of systolic blood pressure was observed with Enzogenol plus vitamin C, but not with vitamin C alone. The blood safety parameters were unchanged. The findings suggest a beneficial effect of supplementation with Enzogenol on cognition in older individuals. Larger studies are needed to ascertain its potential as a preventive treatment for age-related cognitive decline.  相似文献   
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IntroductionMany women experience improved sexual function after hysterectomy. However, a sizeable minority of women report worsened sexual function after the surgery, and concerns about the effect of surgery on sexual function are common among women planning to undergo hysterectomy.AimThe present study examined the role of education about the potential sexual consequences of hysterectomy in predicting self‐reported outcomes and satisfaction with the procedure.MethodsWe conducted a cross‐sectional survey of 204 women who had undergone simple hysterectomy in the preceding 3–12 months. Participants volunteered in response to a Web‐based advertisement.Main Outcome MeasuresParticipants indicated their current sexual function using the Female Sexual Function Index (FSFI), and reported positive and negative sexual outcomes experienced after hysterectomy using a checklist. Participants also completed questionnaire items regarding satisfaction with hysterectomy and education from their physicians about sexual risks and benefits prior to surgery.ResultsCurrent sexual function scores were related to self‐reports of positive and negative sexual outcomes following hysterectomy and overall satisfaction with hysterectomy. Education from a physician about possible adverse sexual outcomes was largely unrelated to self‐reports of having experienced those outcomes. However, education about possible negative sexual outcomes predicted overall satisfaction with hysterectomy when controlling for self‐reports of positive and negative sexual outcomes.ConclusionEducation about potential negative sexual outcomes after surgery may enhance satisfaction with hysterectomy, independent of whether negative sexual outcomes were experienced. Including a discussion of potential sexual changes after surgery may enhance the benefits of presurgical counseling prior to hysterectomy. Bradford A, and Meston C. Sexual outcomes and satisfaction with hysterectomy: Influence of patient education. J Sex Med 2007;4:106–114.  相似文献   
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Production of petroleum-based synthetic rubbers (SRs) causes an enormous carbon footprint for the rubber industry. Carbon footprint would be reduced if natural rubber (NR) could take a larger market share and replace significant quantities of SR. However, some SRs have higher oil resistance than NRs, and, in applications where these properties are needed, chemically modified NR will be required. Epoxidation is a chemical modification of NR which partially converts unsaturated bonds on the backbone of NR to epoxy groups. In this research, epoxidized guayule natural rubber (EGNR)/guayule natural rubber (GNR) blends and GNR were used to make carbon black (CB) filled composites. The processability, mechanical properties, swelling behaviors and dynamic mechanical properties were characterized at various epoxide fractions. Composites made with EGNR/GNR had higher oil resistance, wet traction and stiffness than GNR composites, although tensile strength and elongation at break were reduced by epoxidation. EGNR is expected to lead to the development of new NR products with similar properties to SR, eroding SR markets and increasing the sustainability of the rubber industry.  相似文献   
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Automated voxel-based or predefined volume-of-interest (VOI) analysis of rodent small-animal PET data is necessary for optimal use of information because the number of available resolution elements is limited. We have mapped metabolic ((18)F-FDG), dopamine transporter (DAT) (2'-(18)F-fluoroethyl(1R-2-exo-3-exe)-8-methyl-3-(4-chlorophenyl)-8-azabicyclo[3.2.1]-octane-2-carboxylate [(18)F-FECT]), and dopaminergic D(2) receptor ((11)C-raclopride) small-animal PET data onto a 3-dimensional T2-weighted MRI rat brain template oriented according to the rat brain Paxinos atlas. In this way, ligand-specific templates for sensitive analysis and accurate anatomic localization were created. Registration accuracy and test-retest and intersubject variability were investigated. Also, the feasibility of individual rat brain statistical parametric mapping (SPM) was explored for (18)F-FDG and DAT imaging of a 6-hydroxydopamine (6OHDA) model of Parkinson's disease. METHODS: Ten adult Wistar rats were scanned repetitively with multitracer small-animal PET. Registrations and affine spatial normalizations were performed using SPM2. On the MRI template, a VOI map representing the major brain structures was defined according to the stereotactic atlas of Paxinos. (18)F-FDG data were count normalized to the whole-brain uptake, whereas parametric DAT and D(2) binding index images were constructed by reference to the cerebellum. Registration accuracy was determined using random simulated misalignments and vectorial mismatching. RESULTS: Registration accuracy was between 0.24 and 0.86 mm. For (18)F-FDG uptake, intersubject variation ranged from 1.7% to 6.4%. For (11)C-raclopride and (18)F-FECT data, these values were 11.0% and 5.3%, respectively, for the caudate-putamen. Regional test-retest variability of metabolic normalized data ranged from 0.6% to 6.1%, whereas the test-retest variability of the caudate-putamen was 14.0% for (11)C-raclopride and 7.7% for (18)F-FECT. SPM analysis of 3 individual 6OHDA rats showed severe hypometabolism in the ipsilateral sensorimotor cortex (P 相似文献   
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Genetic testing for hereditary nonpolyposis colorectal cancer   总被引:1,自引:0,他引:1  
Hoedema R  Monroe T  Bos C  Palmer S  Kim D  Marvin M  Luchtefeld M 《The American surgeon》2003,69(5):387-91; discussion 391-2
Approximately 80 per cent of patients with colorectal cancer have sporadic disease whereas the remaining 20 per cent seem to have a genetic component. Hereditary nonpolyposis colorectal cancer (HNPCC) is the most common autosomal dominant hereditary syndrome predisposing to colorectal cancer. Various methods have been described to screen for HNPCC and to directly test for mismatch repair gene mutations. This study evaluates the initial results of 1) microsatellite instability (MSI) and immunohistochemistry (IHC) staining of tumors and 2) genetic sequencing for mismatch repair gene mutations in patients suspected to have HNPCC. Appropriate patients for HNPCC testing were identified through a high-risk colorectal cancer clinic. Of those patients screened only those who met Amsterdam criteria (AC) for HNPCC or were young age onset (YAO) (<40 years of age) were eligible for testing. The tumors underwent testing for MSI and had IHC performed in those patients with available tumor specimens. MSI was performed on the five markers approved by the NIH consensus conference. MSI-High (MSI-H) was defined as two or more markers being unstable. IHC was done with commercially available stains for MLH1 and MSH2. All patients had sequencing of the MLH1 and MSH2 genes performed to search for mutations by a commercial laboratory. Genetic counseling was provided and written informed consent was obtained. Fourteen patients were part of kindreds that met the AC. An additional 10 patients were <40 years of age at diagnosis of colorectal cancer but lacked any family history. Testing for MSI and IHC was performed on those available tissue blocks. Of the AC patients five had MSH2 mutations and two had MLH1 variants. Of the five with MSH2 mutations three of four had MSI-H tumors and all four had loss of expression of MSH2 on IHC. Of the MLH1 variants only one had MSI-H tumor and lacked expression of MLH-1 on IHC. Of those patients with no mutation identified three of six had MSI-H tumors. For those patients YAO no genetic mutations were identified. Two of the seven had MSI-H tumors. Genetic testing for HNPCC even in those patients fulfilling the rigid AC yielded mutations in only five of 14 patients with variants of unknown significance being found in an additional two patients. Only one MSH2 variant of unknown significance was identified in the 10 YAO patients, which would suggest that screening in this group of patients with MSI and/or IHC would be appropriate.  相似文献   
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