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In the USA, partner non-monogamy is reported to be more common among African American women than White women and may contribute to African American women’s increased risk for HIV and other sexually transmitted infections (STIs). Few studies have explicitly and comprehensively described the protective behaviours that African American women employ with non-monogamous partners to reduce their HIV risk. We conducted interviews to examine protective behaviours among 11 African American women aged 18–24 years who perceived that a partner in the preceding 12 months had another sex partner. Participants described three types of partnerships with 29 non-monogamous men; these partnerships clustered into three categories. Narrative analysis revealed an overall paucity of protective behaviours with non-monogamous partners. Protective behaviours (i.e. communication and condom use) were informed by partnership type, rather than perceptions of non-monogamy. There were few instances in which partner non-monogamy motivated women to terminate sex partnerships. Rather, these decisions were often motivated by changes in other relationship dynamics. To address HIV/STI risk related to partner non-monogamy, HIV prevention strategies for young African American women should emphasise the importance of condom use in all non-marital partnership types. Interventions where testing is available may be effective for women who frequently test for HIV/STIs but do not use condoms.  相似文献   
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Background

Pain hypervigilance is an important aspect of the fear-avoidance model of pain that may help explain individual differences in pain sensitivity among persons with knee osteoarthritis (OA).

Purpose

The purpose of this study was to examine the contribution of pain hypervigilance to clinical pain severity and experimental pain sensitivity in persons with symptomatic knee OA.

Methods

We analyzed cross-sectional data from 168 adults with symptomatic knee OA. Quantitative sensory testing was used to measure sensitivity to heat pain, pressure pain, and cold pain, as well as temporal summation of heat pain, a marker of central sensitization.

Results

Pain hypervigilance was associated with greater clinical pain severity, as well as greater pressure pain. Pain hypervigilance was also a significant predictor of temporal summation of heat pain.

Conclusions

Pain hypervigilance may be an important contributor to pain reports and experimental pain sensitivity among persons with knee OA.  相似文献   
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Background:

Partial thickness rotator cuff tears occupy an important position in the spectrum of rotator cuff disease. The development of a more comprehensive classification has been sought to address both the tear location and extent, which may influence clinical results. The purpose of this study is to classify partial thickness rotator cuff tears according to the arthroscopic findings and to evaluate the clinical outcomes after arthroscopic repair of partial thickness tears.

Materials and Methods:

One hundred and two patients had arthroscopic treatment of partial thickness rotator cuff tears. The inclusion criterion for the study was a partially torn supraspinatus tendon involving articular or bursal side, verified by direct arthroscopic visualization. Outcome analysis was exclusively applied to patients who underwent transtendon repair, using the shoulder index of American Shoulder and Elbow Society and the University of California Los Angeles (UCLA) rating system.

Results:

Partial thickness rotator cuff tears were divided into five groups according to arthroscopic findings. There was significant improvement after surgery in all parameters of clinical evaluation in the tears that warranted repair. Arthroscopic repair in situ (transtendon technique) may be the preferred option in unstable partial thickness tear.

Conclusion:

The proposed classification system may assist decision making in the treatment of partial thickness rotator cuff tears.  相似文献   
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Background

M protein mutant vesicular stomatitis virus (M51R-VSV) has oncolytic properties against many cancers. However, some cancer cells are resistant to M51R-VSV. Herein, we evaluate the molecular determinants of vesicular stomatitis virus (VSV) resistance in pancreatic adenocarcinoma cells.

Methods

Cell viability and the effect of β-interferon (IFN) were analyzed using 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium assay. Gene expression was evaluated via microarray analysis. Cell infectability was measured by flow cytometry. Xenografts were established in athymic nude mice and treated with intratumoral M51R-VSV.

Results

Four of five pancreatic cancer cell lines were sensitive to M51R-VSV, whereas Panc 03.27 cells remained resistant (81 ± 3% viability 72 h after single-cycle infection). Comparing sensitive MiaPaCa2 cells with resistant Panc 03.27 cells, significant differences in gene expression were found relating to IFN signaling (P = 2 × 10−5), viral entry (P = 3 × 10−4), and endocytosis (P = 7 × 10−4). MiaPaCa2 cells permitted high levels of VSV infection, whereas Panc 03.27 cells were capable of resisting VSV cell entry even at high multiplicities of infection. Extrinsic β-IFN overcame apparent defects in IFN-mediated pathways in MiaPaCa2 cells conferring VSV resistance. In contrast, β-IFN decreased cell viability in Panc 3.27 cells, suggesting intact antiviral mechanisms. VSV-treated xenografts exhibited reduced tumor growth relative to controls in both MiaPaCa2 (1423 ± 345% versus 164 ± 136%; P < 0.001) and Panc 3.27 (979 ± 153% versus 50 ± 56%; P = 0.002) tumors. Significant lymphocytic infiltration was seen in M51R-VSV–treated Panc 03.27 xenografts.

Conclusions

Inhibition of VSV endocytosis and intact IFN-mediated defenses are responsible for M51R-VSV resistance in pancreatic adenocarcinoma cells. M51R-VSV treatment appears to induce antitumor cellular immunity in vivo, which may expand its clinical efficacy.  相似文献   
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The spatial components of a visual scene are processed neurally in a sequence of coarse features followed by fine features. This coarse‐to‐fine temporal stream was initially considered to be a cortical function, but has recently been demonstrated in the dorsal lateral geniculate nucleus. The goal of this study was to test the hypothesis that coarse‐to‐fine processing is present at earlier stages of visual processing in the retinal ganglion cells that supply lateral geniculate nucleus (LGN) neurons. To compare coarse‐to‐fine processing in the cat's visual system, we measured the visual responses of connected neuronal pairs from the retina and LGN, and separate populations of cells from each region. We found that coarse‐to‐fine processing was clearly present at the ganglion cell layer of the retina. Interestingly, peak and high‐spatial‐frequency cutoff responses were higher in the LGN than in the retina, indicating that there was a progressive cascade of coarse‐to‐fine information from the retina to the LGN to the visual cortex. The analysis of early visual pathway receptive field characteristics showed that the physiological response interplay between the center and surround regions was consistent with coarse‐to‐fine features and may provide a primary role in the underlying mechanism. Taken together, the results from this study provided a framework for understanding the emergence and refinement of coarse‐to‐fine processing in the visual system.  相似文献   
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Introduction

Breast cancer is the most prevalent cancer in women, with slightly more than ten percent developing the disease in Western countries. Mammography screening is a well established method to detect breast cancer.

Aims

The aim of the position statement is to review critically the advantages and shortcomings of population based mammography screening.

Materials and methods

Literature review and consensus of expert opinion.

Results and conclusion

Mammography screening programmes vary worldwide. Thus there are differences in the age at which screening is started and stopped and in the screening interval. Furthermore differences in screening quality (such as equipment, technique, resolution, single or double reading, recall rates) result in a sensitivity varying from 70% to 94% between studies. Reporting results of screening is subject to different types of bias such as overdiagnosis. Thus because of the limitations of population-based mammography screening programmes an algorithm for individualized screening is proposed.  相似文献   
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