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71.
Positive, negative, unknown: assumptions of HIV status among HIV-positive men who have sex with men.
Jeffrey T Parsons Joseph Severino Jose Nanin Joseph C Punzalan Kirk von Sternberg Whitney Missildine David Frost 《AIDS education and prevention》2006,18(2):139-149
Serosorting (i.e., engaging in unprotected sex with partners known to be of the same serostatus) can be a difficult process for men who have sex with men (MSM) who frequently make assumptions about their partners' serostatus. This process can be further complicated by a partner's dishonesty as well as other individual and contextual factors. The present study specifically examined how assumptions of serostatus made about unknown serostatus partners impact on the sexual behavior of 110 alcohol-abusing HIV-positive MSM. Although previous research has shown that HIV-positive MSM are more likely to serosort with other known HIV-positive men than with known HIV-negative men, our data suggest that unprotected sex behavior may not be specifically driven by whether or not they made assumptions of seroconcordance or serodiscordance. The types of assumptions these HIV-positive MSM made about their unknown status sexual partners and the basis for such assumptions were also examined. Owing to the ambiguities involved in assumptions of a partner's serostatus in sexual encounters, the 'unknown status' partner category is analytically distinct from 'known status' categories, and needs to be more fully explored because of its impact on perceived serosorting, rather than actual serosorting, among HIV-positive men. 相似文献
72.
K Radon S Huemmer H Dressel D Windstetter G Weinmayr S Weiland E Riu C Vogelberg W Leupold E von Mutius M Goldberg D Nowak 《The European respiratory journal》2006,27(4):774-778
Existing guidelines advise adolescents with asthma and allergies against high-risk occupations. The aim of the current authors' analyses was to investigate the resulting self-selection in a prospective cohort study. The participants of Phase II of the International Study of Asthma and Allergies in Childhood in Germany (aged 9-11 yrs at baseline) were re-contacted after 7 yrs (response rate was 77%) and were asked to complete a questionnaire, which included items on atopic diseases. The subjects were also asked about the type of job they would like to have in the future (preferred job choice). Exposure to agents with potential asthma risk was evaluated using a job exposure matrix. The analyses were restricted to those in school-based vocational training programmes without occupational exposures. A total of 33% of subjects chose jobs with high asthma risk, 23% selected low asthma risk jobs and the remaining adolescents indicated jobs without known asthma risk (reference category). There were no statistically significant associations between asthma, allergic rhinitis or atopic dermatitis and selecting jobs with asthma risk. Participants with allergic rhinitis tended to select high risk jobs less frequently. In conclusion, self-selection into low risk jobs seems to play a minor role in teenagers with asthma or allergies. 相似文献
73.
74.
Massimo Lemma Andrea Mangini Guido Gelpi Andrea Innorta Paolo Danna Francesco Lavarra Emanuela Piccaluga Carlo Antona 《European journal of cardio-thoracic surgery》2003,24(1):81-5; discussion 85
OBJECTIVE: It is not well established whether the blood flow of arterial composite Y-grafts can efficiently respond to the flow demand of the coronary system early postoperatively. The aim of this study was to evaluate if soon after the operation, arterial composite Y-grafts can increase blood flow in response to an increase in myocardial oxygen consumption (MVO2). METHODS: Twenty-seven patients who received complete arterial myocardial revascularization using the left internal thoracic artery (LITA) and the radial artery (RA) as composite Y-graft gave their consent to a pre-discharge coronary angiography and intravascular flow velocity measurements using a Doppler guide wire. Flow measurements were performed in the LITA main stem, the distal LITA and the RA, both at rest and during atrial pacing at the 85% of the patient age-predicted maximum. The heart rate-systolic blood pressure product was considered as an indirect index of MVO2. Hyperemic flow was determined after injection of adenosine. The flow reserve (FR) was defined as the ratio of blood flow during maximal hyperemia (Qmax) to baseline flow (Qbasal). RESULTS: Atrial pacing increased MVO2 significantly (P<0.000). None of the patients developed ischemic S-T segment modifications or complained of chest pain. Q(basal) increased significantly in the LITA main stem (P=0.001), distal LITA (P=0.041) and RA (P=0.004) while Qmax did not change significantly. As a consequence, the FR decreased in the LITA main stem (P=0.002), distal LITA (P<0.000) and RA (P<0.000) but was not completely exhausted. CONCLUSIONS: Soon after the operation, arterial composite Y-grafts can significantly increase blood flow in response to conditions of increased MVO2, keeping normal the myocardial O2 supply-to-demand ratio. 相似文献
75.
Trauma und Berufskrankheit - Zusammenfassung Diese Arbeit beschäftigt sich mit der Häufigkeit, dem Entstehungsmechanismus und der Behandlung von Bizepssehnenrupturen. Veränderte... 相似文献
76.
Macrophage response to microtextured silicone 总被引:1,自引:0,他引:1
Seven different silicone surface textures were tested for effect on macrophage spreading and metabolic activity in vitro. Variables of the textured arrays that could modify spreading were determined to be the size, spacing between, depth, density, and orientation of the individual surface events and the roughness of the surfaces. Cells were influenced by the size of the events and the roughness of the surfaces more than any other variables. Cell morphology data, surface area and perimeter, could be divided into discrete regions that correlated well with the size of the events. Cell dimensions on 5μm textures were smallest while those on smooth silicone and glass surfaces were the largest. Surface texture events may be modifying contact guidance of the cells or interacting with specific transmembrane proteins to alter cell shape and function. The mitochondrial activity of cells attached to the textured silicones was determined by measuring the amount of reduced MTT directly through live cells. Cells on polystyrene (PS), 5VP and 8VP textures were metabolically more active than cells on the other textures. PMA was used to stimulate cells on the various textures. PMA-stimulated cells, on the smaller textures, 2VP, 5VP and 5CP, were less active than test cells that were not stimulated. The inability of PMA to stimulate these cells may be due to a structural alteration of protein kinase C. An hypothesis is introduced that includes a possible mechanism of how a micrometre-sized surface texture could modify cell function. 相似文献
77.
Seth M Brown Babak Sadoughi Hernando Cuellar Ron von Jako Marvin P Fried 《Otolaryngology--head and neck surgery》2007,136(2):268-273
OBJECTIVE: One of the main limitations of image-guided surgery is that navigation relies on the use of a CT scan obtained before surgery and is unable to be updated during the procedure. A software addition has been developed to allow reconstruction of CT-like images from a series of fluoroscopic scans and integrate these into an image-guided system (GE Healthcare Surgical Navigation, Lawrence, MA). We report our initial experience with a series of patients undergoing intraoperative fluoroscopic navigation in sinus surgery. STUDY DESIGN AND SETTINGS: After institutional review board clearance, we prospectively studied 14 consecutive patients undergoing image-guided sinus surgery with the use of intraoperative fluoroscopy. RESULTS: All patients had preoperative and postoperative fluoroscopic images reconstructed into CT-like images. By the conclusion of the study, images were adequate in quality and accurate navigation was achieved. CONCLUSION: Real-time image-guided sinus surgery using fluoroscopy is feasible. Future studies will need to focus on defining the procedures that could benefit, such as tumor resection, to enhance patient safety during these operations. 相似文献
78.
Efficacy of interventions with caregivers: a reanalysis 总被引:2,自引:0,他引:2
This paper presents a reanalysis of data from a previously reported study with family caregivers of dementia patients using the method of prediction analysis. Compared with subjects on a waiting list or enrolled in support groups, caregivers in individual and family counseling were more likely to have successful outcomes on all dependent measures (Brief Symptom Inventory, personal strain, and role strain). 相似文献
79.
Claudio Babiloni Giuliano Binetti Emanuele Cassetta Gloria Dal Forno Claudio Del Percio Florinda Ferreri Raffaele Ferri Giovanni Frisoni Koichi Hirata Bartolo Lanuzza Carlo Miniussi Davide V Moretti Flavio Nobili Guido Rodriguez Gian Luca Romani Serenella Salinari Paolo M Rossini 《Clinical neurophysiology》2006,117(2):252-268
OBJECTIVE: The present study tested the hypothesis that cortical electroencephalographic (EEG) rhythms. change across normal elderly (Nold), mild cognitive impairment (MCI), and Alzheimer's disease (AD) subjects as a function of the global cognitive level. METHODS: Resting eyes-closed EEG data were recorded in 155 MCI, 193 mild AD, and 126 age-matched Nold subjects. EEG rhythms of interest were delta (2-4 Hz), theta (4-8 Hz), alpha 1 (8-10.5 Hz), alpha 2 (10.5-13 Hz), beta 1 (13-20 Hz), and beta 2 (20-30 Hz). EEG cortical sources were estimated by LORETA. RESULTS: Occipital delta and alpha 1 sources in parietal, occipital, temporal, and 'limbic' areas had an intermediate magnitude in MCI subjects compared to mild AD and Nold subjects. These five EEG sources presented both linear and nonlinear (linear, exponential, logarithmic, and power) correlations with the global cognitive level (as revealed by mini mental state examination score) across all subjects. CONCLUSIONS: Cortical EEG rhythms change in pathological aging as a function of the global cognitive level. SIGNIFICANCE: The present functional data on large populations support the 'transitional hypothesis' of a shadow zone across normality, pre-clinical stage of dementia (MCI), and AD. 相似文献
80.
A R von Hochstetter 《Zeitschrift für Orthop?die und ihre Grenzgebiete》1990,128(3):305-307
Compared to other forms of cancer, malignant mesenchymal tumors are rare: individual surgeons see few such patients and do not usually treat them personally. The radiologic and histologic problems of differential diagnosis, and the subtle distinction between benign and malignant make decision an onerous task for surgeons, orthopedists, pathologists, oncologists and radiotherapists. For this reason referral centers should enable oncologic working groups to confirm diagnoses, establish appropriate therapeutic schedules, and to help in follow-up patient care. Around 1970, a center was created at Balgrist University Orthopedic Clinic for the gathering, documentation and coordination of clinical and pathological data from patients with tumors and tumorous lesions of the skeleton and soft tissues. Subsequently, a circle of continuously collaborating specialists, including some from other institutions, formed about the register. The viability of the reference center is assured by unequivocal morphologic diagnosis; presence of the pathologist during the planning and procedure of the biopsy and other tumor-related interventions in the operating room; clinical investigations including the immediate availability of diagnostic procedures; charting all clinical data; and the clinic's follow-up of its own patients. Fully integrated in the Orthopedic Clinic and Polyclinic, the register is a major instrument in the treatment of patients at risk with tumor. Given the diversity of clinicopathological presentation, the register permits direct access to analogous situations in individual cases. 相似文献