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In US men, the incidence of anal cancer, the primary cause of which is human papillomavirus (HPV) infection, has increased almost 3-fold in 3 decades; however, little is known about the epidemiology of anal HPV infection, especially in heterosexual men. In 2 US cities, behavioral data and anal biological specimens were collected from 253 men who acknowledged having engaged in sexual intercourse with a woman during the preceding year. On the basis of DNA analysis, overall prevalence of anal HPV infection was found to be 24.8% in 222 men who acknowledged having had no prior sexual intercourse with men. Of the men with anal HPV infection, 33.3% had an oncogenic HPV type. Risk factors independently associated with anal HPV were lifetime number of female sex partners and frequency of sex with females during the preceding month. These results suggest that anal HPV infection may be common in heterosexual men.  相似文献   
75.
The increasing aging population, the prevalence of chronic diseases and rising costs have brought about some unique health care challenge to our global society. In response to the unmet health care needs, researchers are actively seeking for innovative solutions that target for (1) prevention of diseases and (2) personalized diagnosis and treatment. It is envisaged that by taking preventive measures for health monitoring, diagnosing and treating patients with a personalized approach at an early stage of disease development, health care will be more cost effective and sustainable. The authors provide an overview of the advancements in Information and Communication Technology (ICT), and explain how some innovative health solutions, through the use of Telemedicine, can now be an opportunity for patients and their family.  相似文献   
76.
Mast cells (MCs) reside in tissues that are common targets of Candida spp. infections, and can exert bactericidal activity, but little is known about their fungicidal activity. MCs purified from rat peritoneum (RPMC) and a clinical isolate of C. albicans, were employed. Ingestion was evaluated by flow cytometry (FACS) and optical microscopy. The killing activity was assayed by FACS analysis and by colony forming unit method. RPMC degranulation was evaluated by β-hexosaminidase assay and phosphatidylserine externalization by FACS. Phagocytosing RPMC were also analyzed by transmission electron microscopy. Herein, we show that the killing of C. albicans by RPMC takes place in the extracellular environment, very likely through secreted granular components. Ultrastructural analysis of the ingestion process revealed an unusual RPMC–C. albicans interaction that could allow fungal survival. Our findings indicate that MCs have a positive role in the defense mechanism against Candida infections and should be included among the cell types involved in host-defense against this pathogen.  相似文献   
77.

OBJECTIVE:

To compare normal and delayed bone healing by measuring ultrasound conduction velocity across the bone callus.

METHODS:

A model of transverse linear and 5 mm resection osteotomies of sheep tibiae was used. Fourteen sheep were operated on and were divided into two groups of seven according to osteotomy type. The procedure was performed on the right tibiae and the intact left tibiae were used as controls. The transverse and axial ultrasound velocities were measured at 30-day intervals for 90 days, after which the animals were killed and both the right and left tibiae were resected for in vitro biomechanical analysis.

RESULTS:

Both the transverse and axial ultrasound velocities progressively increased, but the increase was smaller for the delayed union that resulted from the resection osteotomy. The mechanical resistance was higher for the normally healed tibiae that resulted from a linear osteotomy; this result closely correlated with the ultrasound velocity results. Significant differences were found for the comparisons between the intact and operated tibiae in both groups and between the groups for both the transverse and axial ultrasound velocities, but the differences were greater for the latter.

CONCLUSION:

We conclude that in vivo transverse and axial ultrasound velocities provide highly precise information about the healing state of both linear and resection diaphyseal osteotomies, but the axial ultrasound velocity most likely has greater discriminatory power. This method has the potential for clinical application in humans.  相似文献   
78.
Incidence of human papillomavirus (HPV) attributable oropharyngeal cancers (OPCs) has been increasing globally, especially among men in high-income countries. There is a lack of studies comparing oral HPV prevalence by age and country among healthy men. The purpose of our study was to assess oral HPV prevalence by country and age. Participants of the HPV Infection in Men Study (HIM), a cohort of 3,098 healthy men from São Paulo, Brazil, Cuernavaca, Mexico and Tampa, USA, were studied. Oral HPV prevalence and type distribution were assessed using the SPF10 PCR-DEIA-LiPA25 system. The prevalence of any HPV in Brazil, Mexico and the US was 8.7% (95% CI: 7.1%, 10.4%), 10.0% (95% CI: 8.3%, 12.1%) and 7.6% (95% CI: 5.9%, 9.5%), respectively, while the prevalence of high-risk HPV was 5.3% (95% CI: 4.1%, 6.7%), 7.3% (95% CI: 5.7%, 9.0%) and 5.4% (95% CI: 4.0%, 7.0%), respectively. No significant differences in prevalence of grouped HPV types were observed by country despite significant differences in sexual behaviors. However, the age-specific prevalence of oral HPV differed by country. Brazilian (6.0% [95% CI: 3.4%, 9.7%]) and Mexican (9.2% [95% CI: 5.6%, 14.0%]) participants had peak high-risk HPV prevalence among men aged 41–50 years whereas the US participants had peak prevalence at ages 31–40 years (11.0% [95% CI: 6.4%, 17.3%]). In conclusion, oral HPV prevalence was low with no difference in overall prevalence observed by country. Factors associated with the differences in oral HPV age-patterning by country and sexual orientation require further study.  相似文献   
79.
Dose-dense adjuvant chemotherapy is standard of care in high-risk early breast cancer patients. However, its role in HER2-positive patients is still uncertain. In this exploratory analysis of the GIM2 trial, we investigated the efficacy of dose-dense chemotherapy in HER2-positive breast cancer patients with or without exposure to trastuzumab. In the GIM2 trial, node-positive early breast cancer patients were randomized to receive four cycles of (fluorouracil)epirubicin/cyclophosphamide followed by four cycles of paclitaxel administered every 2 (dose-dense) or 3 (standard-interval) weeks. After approval of adjuvant trastuzumab, protocol was amended in April 2006 to allow use of trastuzumab for 1 year after chemotherapy completion in HER2-positive patients. The efficacy of dose-dense chemotherapy in terms of disease-free survival (DFS) and overall survival (OS) was assessed according to HER2 status and trastuzumab use. Out of 2,003 breast cancer patients, HER2 status was negative/unknown in 1,551 patients; among the 452 patients with HER2-positive breast cancer, chemotherapy alone or followed by trastuzumab was given to 320 and 132 patients, respectively. Median follow-up was 8.1 years. No significant interaction between HER2 status, trastuzumab use and chemotherapy treatment was observed for both DFS (p = 0.698) and OS (p = 0.708). Nevertheless, there was no apparent benefit in the HER2-positive group treated with trastuzumab (DFS: HR, 0.99; 95% CI 0.52–1.89; OS: HR, 0.95; 95% CI 0.37–2.41). Although dose-dense chemotherapy was associated with a significant survival improvement in high-risk breast cancer patients, its benefit appeared to be smaller (if any) in patients with HER2-positive disease who received adjuvant trastuzumab.  相似文献   
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