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61.
Human papillomavirus (HPV) testing is very sensitive for primary cervical screening but has low specificity. Triage tests that improve specificity but maintain high sensitivity are needed. Women enrolled in the experimental arm of Phase 2 of the New Technologies for Cervical Cancer randomized controlled cervical screening trial were tested for high-risk HPV (hrHPV) and referred to colposcopy if positive. hrHPV-positive women also had HPV genotyping (by polymerase chain reaction with GP5+/GP6+ primers and reverse line blotting), immunostaining for p16 overexpression and cytology. We computed sensitivity, specificity and positive predictive value (PPV) for different combinations of tests and determined potential hierarchical ordering of triage tests. A number of 1,091 HPV-positive women had valid tests for cytology, p16 and genotyping. Ninety-two of them had cervical intraepithelial neoplasia grade 2+ (CIN2+) histology and 40 of them had CIN grade 3+ (CIN3+) histology. The PPV for CIN2+ was >10% in hrHPV-positive women with positive high-grade squamous intraepithelial lesion (61.3%), positive low-grade squamous intraepithelial lesion (LSIL+) (18.3%) and positive atypical squamous cells of undetermined significance (14.8%) cytology, p16 positive (16.7%) and, hierarchically, for infections by HPV33, 16, 35, 59, 31 and 52 (in decreasing order). Referral of women positive for either p16 or LSIL+ cytology had 97.8% sensitivity for CIN2+ and women negative for both of these had a 3-year CIN3+ risk of 0.2%. Similar results were seen for women being either p16 or HPV16/33 positive. hrHPV-positive women who were negative for p16 and cytology (LSIL threshold) had a very low CIN3+ rate in the following 3 years. Recalling them after that interval and referring those positive for either test to immediate colposcopy seem to be an efficient triage strategy. The same applies to p16 and HPV16.  相似文献   
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64.
So far, only three small outdated studies have investigated hepatitis C virus (HCV) incidence and risk factors among illicit drug users (DUs) in Italy. Thus, during 2007–2010, we conducted a prospective cohort study among DUs attending 17 Italian rehabilitation centers serving urban areas. Two hundred eighty-four HCV-uninfected DUs were prospectively followed by interview and anti-HCV antibody and RNA testing every 6 months. Incidence was calculated using the person-years method. Infection predictors were assessed by time-dependent Cox analysis. Participants were mostly male (83.4%), under opioid substitution therapy (OST) (78.9%), non-injecting DUs (67.9%), and with a mean age of 30.8. Ninety-one of 224 DUs initially under OST interrupted treatment during the follow-up. Overall HCV incidence was 5.83/100 person-years at risk (PYAR) [95% confidence intervals (CI), 3.63–9.38]. The incidence did not significantly differ according the participants’ sociodemographic characteristics or the degree of urbanization of the towns involved in the study. The incidence was higher for DUs under than for those not under OST (6.23 vs 4.50/100 PYAR; p = 0.681). Incidence was also higher for those with than for those without OST interruption (7.17 vs 5.04/100 PYAR; p = 0.55). However, all these differences were non-significant. At last follow-up visit, a significant decrease in frequency of sharing equipment for preparation/using drugs (by injection or not) was observed by analyzing either the whole cohort or DUs under OST only. Anti-HCV seroconversion resulted independently associated with sharing drug preparation/use equipment, backloading, having a HCV-positive sexual partner, or household and (marginally) intravenous injection. In this study, HCV incidence was non-negligible and OST seemed to lack effectiveness in reducing it. In Italy, implementation of combined harm reduction interventions and antiviral treatment of chronically infected DUs would be needed.  相似文献   
65.

Background

Although the close relationship between mobility and cognitive declines is well-known, literature has very little questioned whether improvement in walking speed over time could be associated with improvements in cognitive functions. The objective of this study was to examine the associations between a clinically meaningful improvement in walking speed and global and specific cognitive changes in older adults. Design: Prospective cohort study.

Setting

Multidomain Alzheimer Preventive Trial (MAPT) study.

Participants

Three-hundred participants from the control group of the MAPT study (mean age 74.8 ± 4.2; 57% women).

Measurements

The 4-m usual walking speed, global cognition, memory, executive functions, and processing speed measures were collected at baseline, and at 6, 12, 24 and 36 months. Participants were categorized into three groups according to their walking speed change over the three-year study: 1/ Non-Improvers (participants not presenting an increase ≥0.05m/sec on walking speed; n=138); 2/ Improvers (increase ≥0.05m/sec; n=40); Cyclic (≥0.05m/sec improvement at some time points without maintaining it through the whole period; n=122).

Results

Adjusted mixed-effect linear regressions revealed that walking speed improvers did not significantly differ from participants who never or temporarily improved their walking speed on all of global and specific cognitive functions over three years. Nevertheless, a sensitivity analysis (excluding participants with a nonclinical walking speed improvement) indicated specific cognitive trajectories per group associated with better episodic memory scores for Improvers compared to non-improvers (β=2.41, 95% CI=.12 - 4.71; p=.039).

Conclusion

This study found that the overtime trajectories of cognitive functions did not differ as a function of clinically meaningful walking speed changes in older adults. Nevertheless, secondary analyses provided new insights on the relationship between walking speed and specific cognitive functions. The novelty of this approach (switching from declines to improvements) should be considered in future large-scale, observational longitudinal studies.
  相似文献   
66.

Purpose

Although mental health problems such as depression after disasters have been reported, positive psychological factors after disasters have not been examined. Recently, the importance of positive affect to our health has been recognised. We therefore investigated the frequency of laughter and its related factors among residents of evacuation zones after the Great East Japan Earthquake of 2011.

Methods

In a cross-sectional study on 52,320 participants aged 20 years and older who were included in the Fukushima Health Management Survey in Japan’s fiscal year 2012, associations of the frequency of laughter with changes in lifestyle after the disaster, such as a changed work situation, the number of family members, and the number of address changes, and other sociodemographic, psychological, and lifestyle factors were examined using logistic regression analysis. The frequency of laughter was assessed using a single-item question: “How often do you laugh out loud?”

Results

The proportion of those who laugh almost every day was 27.1%. Multivariable models adjusted for sociodemographic, psychological, and lifestyle factors demonstrated that an increase in the number of family members and fewer changes of address were significantly associated with a high frequency of laughter. Mental health, regular exercise, and participation in recreational activities were also associated with a high frequency of laughter.

Conclusion

Changes in lifestyle factors after the disaster were associated with the frequency of laughter in the evacuation zone. Future longitudinal studies are needed to examine what factors can increase the frequency of laughter.
  相似文献   
67.

Background

To investigate the association of lung cancer with occupational exposure to textile dust and specifically to cotton dust in the population‐based case‐control study ICARE.

Methods

Lifelong occupational history of 2926 cases and 3555 controls was collected using standardized questionnaires, with specific questions for textile dust exposure. Odds ratios (ORs) and 95% confidence intervals (CI) were estimated using unconditional logistic regression models controlling for confounding factors including smoking and asbestos exposure.

Results

An inverse association between textile dust exposure and lung cancer was found among workers exposed ≥5% of their work time (OR = 0.80, 95%CI = 0.58‐1.09), more pronounced for distant exposures (40+ years; up to a 56% reduced risk, statistically significant). The OR of lung cancer was significantly decreased among workers exposed to cotton fibers (OR = 0.70, 95%CI = 0.48‐0.97).

Conclusions

Our results provide some evidence of a decreased risk of lung cancer associated with exposure to textile dust, particularly cotton.
  相似文献   
68.
69.
OBJECTIVES: To compare the clinical outcomes of standard, cylindrical, screw-shaped to novel tapered, transmucosal (Straumann Dental implants immediately placed into extraction sockets. Material and methods: In this randomized-controlled clinical trial, outcomes were evaluated over a 3-year observation period. This report deals with the need for bone augmentation, healing events, implant stability and patient-centred outcomes up to 3 months only. Nine centres contributed a total of 208 immediate implant placements. All surgical and post-surgical procedures and the evaluation parameters were discussed with representatives of all centres during a calibration meeting. Following careful luxation of the designated tooth, allocation of the devices was randomly performed by a central study registrar. The allocated SLA titanium implant was installed at the bottom or in the palatal wall of the extraction socket until primary stability was reached. If the extraction socket was >or=1 mm larger than the implant, guided bone regeneration was performed simultaneously (Bio Oss and BioGide. The flaps were then sutured. During non-submerged transmucosal healing, everything was done to prevent infection. At surgery, the need for augmentation and the degree of wound closure was verified. Implant stability was assessed clinically and by means of resonance frequency analysis (RFA) at surgery and after 3 months. Wound healing was evaluated after 1, 2, 6 and 12 weeks post-operatively. RESULTS: The demographic data did not show any differences between the patients receiving either standard cylindrical or tapered implants. All implants yielded uneventful healing with 15% wound dehiscences after 1 week. After 2 weeks, 93%, after 6 weeks 96%, and after 12 weeks 100% of the flaps were closed. Ninety percent of both implant designs required bone augmentation. Immediately after implantation, RFA values were 55.8 and 56.7 and at 3 months 59.4 and 61.1 for cylindrical and tapered implants, respectively. Patient-centred outcomes did not differ between the two implant designs. However, a clear preference of the surgeon's perception for the appropriateness of the novel-tapered implant was evident. CONCLUSIONS: This RCT has demonstrated that tapered or standard cylindrical implants yielded clinically equivalent short-term outcomes after immediate implant placement into the extraction socket.  相似文献   
70.
面横裂畸形围产儿的流行病学调查分析   总被引:4,自引:0,他引:4  
目的 利用1987-1992年中国出生缺陷监测网收集的资料,描述国产儿面横裂畸形的流行病学特征及其多发畸形模式.方法 采用以医院为基础的监测方法收集资料,调查孚8周到产后7d住院分娩的围产儿(包括活产、死胎和死产)。结果 共收集围产儿4489692个,面横裂畸形94例,全国发生率为0.21/万,城镇发生率为0.20/万,乡村发生率为0.23万。男性和女性发生率均为0.20/万。69例畸形儿合并有其他畸形,其中53.6%伴有耳部异常,围产期病死率为46.8%,单发(16.0%)和多发(58.0%)的面横裂病死率明显不同。结论 中国围产儿面横裂畸形发生率高于文献的估计值,未发现城乡差异和性别差异。面横裂以多发畸形为主,常作为其他综合征的特征畸形之一。  相似文献   
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