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81.
Ana P Martinez-Donate Melbourne F Hovell Elaine J Blumberg Jennifer A Zellner Carol L Sipan Audrey M Shillington Claudia Carrizosa 《AIDS education and prevention》2004,16(2):172-186
Adolescents are at increasing risk for HIV infection in Mexico. Research on gender differences in risk behaviors and determinants is needed to develop effective HIV prevention interventions targeting Mexican adolescents. This study examined gender differences in the likelihood of unprotected sex and theoretical correlates among high school students in the border city of Tijuana. Three hundred seventy high-school students completed a face-to-face interview and a self-administered survey. Differences in sexual initiation, condom use, intentions to use condoms in the future, and attitudes towards condoms in this population were assessed. Although male students initiated sexual practices earlier than females, females were more likely to have unprotected sex. Females perceived themselves as more likely to avoid unprotected sex in the future and held more favorable attitudes about condoms. The results suggest that stereotypical gender roles and communication barriers place Tijuana female high school students at higher risk for HIV infection than their male peers. 相似文献
82.
Michael Gerharz MD ; Ankev Baranowsky PhD ; Udo Siebolts MD ; Sabine Eming MD ; Roswitha Nischt PhD ; Thomas Krieg PhD ; Claudia Wickenhauser MD 《Wound repair and regeneration》2007,15(1):105-112
Morphometric data based on skin wounding offer important information for the characterization of the phenotype of transgenic mouse models. The goal of this study was the comparison of technical procedures concerning wounding, processing, and evaluation of samples in different mouse strains. The multitissue array technique was used to estimate its adaptability for standardized analysis in wound healing. Skin wounds between days 1 and 14 after wounding were analyzed. The influence of mouse strain (C57BI/6 vs. FVB/N mice), sex, size of the punch biopsies, and preparation of the tissue sections was investigated on 94 mice. The parameters distance between the migration tongues (deltaMT) and surface not covered by epithelium were evaluated to describe the reepithelialization, and the distance between the adnexa was chosen to measure wound contraction. In addition, the techniques to measure the area of granulation tissue (GT) were evaluated. The data illustrate the requirement of standardized conditions for skin wound-healing experiments and demonstrate that histological preparation in serial sections is mandatory to detect slight differences in wound contraction. For the analysis of cellular composition in GT, multitissue arrays are useful tools in wound-healing studies. 相似文献
83.
84.
Journal of Neurology - Fatigue is a widespread symptom in numerous neuroimmunological diseases like multiple sclerosis (MS), myasthenia gravis, morbus Behcet, neurosarcoidosis, neuroborreliosis or... 相似文献
85.
Marcelo Miranda MD Claudia Castiglioni MD Beat M. Frey MD Martin Hergersberg PhD Adrian Danek MD Hans H. Jung MD 《Movement disorders》2007,22(9):1358-1361
The X‐linked McLeod neuroacanthocytosis syndrome strongly resembles Huntington's disease and has been reported in various countries world‐wide. Herein, we report two Chilean brothers with predominant psychiatric features at disease onset including schizophrenia‐like psychosis and obsessive compulsive disorder. Molecular genetic analysis revealed a small deletion in the XK gene (938‐942delCTCTA), which has been already described in a North American patient of Anglo‐Saxon descent and a Japanese family, presenting with seizures, muscle atrophy or chorea yet absence of psychiatric features. These findings argue against a founder effect and indicate a profound phenotypic variability associated with the 938‐942delCTCTA deletion. Our report supports the inclusion of McLeod syndrome in the differential diagnosis of Huntington's disease as well as acute psychosis in male subjects. © 2007 Movement Disorder Society 相似文献
86.
Matthias Siepe Claudia Heilmann Patrick von Samson Philippe Menasché Friedhelm Beyersdorf 《European journal of cardio-thoracic surgery》2005,28(2):318-324
Several human organs are not capable of functional regeneration following a tissue defect and react with scar formation. In stem cell transplantation, undifferentiated or partly differentiated precursor cells are applied to defective tissue for therapeutic regeneration. After promising preclinical investigations, the transplantation of autologous stem cells for myocardial infarction treatment is being transferred to clinical use. Mesenchymal stem cells and endothelial precursor cells derived from the bone marrow or circulating blood as well as skeletal myoblasts are employed in clinical trials. Furthermore, indications for cell transplantation and delivery routes vary considerably throughout current investigations. Initial results suggest a potential for restoration of cardiac function in stem cell-treated patients; however, the mechanisms are not fully understood. This overview will focus on objectives, recent achievements, and future perspectives of diverse stem cell transplantation approaches. 相似文献
87.
Ramirez Claudia C. MD Ma Fangchao MD PhD Federman Daniel G. MD † Kirsner Robert S. MD PhD ‡§ 《Dermatologic surgery》2005,31(7):748-753
Background Results from in vitro and animal studies suggest that cyclooxygenase (COX) inhibitors may reduce the risk of melanoma, but among humans, the evidence remains limited.
Objective In a pilot retrospective cohort, to determine the relationship between the use of COX inhibitors and the incidence, recurrence, and metastases of melanoma in high-risk patients.
Methods Reviewing computerized records at the Miami Veterans Affairs Medical Center, we retrospectively examined the association between COX inhibitor use and melanoma incidence, recurrence, and metastases in high-risk subjects: white subjects previously diagnosed with melanoma (1996–2003). We evaluated three potential outcomes: new melanoma diagnosis, recurrence of a previous melanoma, and melanoma metastasis.
Results Eighty-three subjects with melanoma were included. There was one metastasis among 28 subjects prescribed COX inhibitors, whereas four new melanomas (7.3%), two melanoma recurrences, and six metastases (10.9%) occurred among 55 patients not prescribed COX inhibitors. Although no individual outcomes measures reached statistical significance, combining the three measures, these were significantly lower in users of COX inhibitors compared with nonusers (1 vs 12; p = .05 ). After adjustment for age and tumor depth of invasion, COX inhibitor users had significantly lower rates of melanoma outcome measures (odds ratio 0.08; 95% confidence interval 0.01–0.77; p = .03 ).
Conclusion Potential exists for chemoprevention of melanoma among high-risk patients. 相似文献
Objective In a pilot retrospective cohort, to determine the relationship between the use of COX inhibitors and the incidence, recurrence, and metastases of melanoma in high-risk patients.
Methods Reviewing computerized records at the Miami Veterans Affairs Medical Center, we retrospectively examined the association between COX inhibitor use and melanoma incidence, recurrence, and metastases in high-risk subjects: white subjects previously diagnosed with melanoma (1996–2003). We evaluated three potential outcomes: new melanoma diagnosis, recurrence of a previous melanoma, and melanoma metastasis.
Results Eighty-three subjects with melanoma were included. There was one metastasis among 28 subjects prescribed COX inhibitors, whereas four new melanomas (7.3%), two melanoma recurrences, and six metastases (10.9%) occurred among 55 patients not prescribed COX inhibitors. Although no individual outcomes measures reached statistical significance, combining the three measures, these were significantly lower in users of COX inhibitors compared with nonusers (1 vs 12; p = .05 ). After adjustment for age and tumor depth of invasion, COX inhibitor users had significantly lower rates of melanoma outcome measures (odds ratio 0.08; 95% confidence interval 0.01–0.77; p = .03 ).
Conclusion Potential exists for chemoprevention of melanoma among high-risk patients. 相似文献
88.
Gardenia C. G. Militão Daniel P. Bezerra Claudia Pessoa Manoel Odorico de Moraes Flavio A. F. da Ponte Mary Anne S. Lima Edilberto R. Silveira Letícia V. Costa-Lotufo 《Journal of natural medicines》2007,61(2):196-199
The purpose of this study was to investigate the antiproliferative activity of 2,3,9-trimethoxypterocarpan, a known pterocarpan
with cytotoxic activity against many tumor cell lines, in a panel of four leukemia cell lines (HL-60, Molt-4, Jurkat, and
K562) and on human peripheral blood mononuclear cells (PBMC). The pterocarpan showed IC50 ranging from 0.1 to 0.5 μg/ml at leukemic cells after 72 h of incubation, with K562 being the most resistant cell line. This
compound seemed to be selective to tumor cell lines, since at a concentration of 10 μg/ml after 72 h, it only reduced 19%
of viable peripheral mononuclear cells. 相似文献
89.
Rosa van Mourik Jaap Oosterlaan Dirk J Heslenfeld Claudia E Konig Joseph A Sergeant 《Clinical neurophysiology》2007,118(8):1855-1865
OBJECTIVE: Although an increased distractibility is one of the behavioral criteria of Attention Deficit Hyperactivity Disorder (ADHD), there is little empirical evidence that children with ADHD are in fact more distractible than their normal peers. METHODS: We recorded event-related potentials (ERPs) to distracting novel sounds (novels) and standard sounds, (standards) while children performed a visual two-choice reaction time task. Twenty-five children with ADHD were compared with eighteen normal controls (aged 8-12 years). RESULTS: Children with ADHD showed a larger early P3a (150-250 ms), both in response to the standard and in response to the novel. The late phase of the P3a had a larger amplitude in the ADHD group in the 250-300 ms window compared to the control group, which was only present in response to the novel. Interestingly, the novel reduced the errors of omission in the ADHD group to a greater extent than in the normal control group. CONCLUSIONS: Although children with ADHD show an increased orienting response to novels, this distracting information can enhance their performance temporarily, possibly by increasing their arousal to an optimal level, as indicated by the reduced omission rate. SIGNIFICANCE: These data indicate that distraction is not always distracting in children with ADHD and that distraction can also have beneficial effects. 相似文献
90.
Davicino Roberto Patricia Micucci Turner Sebastian Ferraro Graciela Claudia Anesini 《Basic & clinical pharmacology & toxicology》2010,106(1):38-44
Abstract: Limonene is a monoterpene present in citrus fruit and is used as flavouring agents of foods. It was shown that monoterpenes possess antioxidant activity. Previously, it was demonstrated that limonene exerts anti‐proliferative action on a lymphoma cell line without modifying normal lymphocyte viability. H2O2 has a modulator role in cell proliferation. In the present study, the effect of limonene on normal lymphocytes proliferation and its relation with H2O2 level modulation was analysed, evaluating its effect on the activity of cell antioxidant enzymes, such as catalase, peroxidase and superoxide dismutase. Limonene exerted a biphasic effect on cell proliferation; the increase in cell proliferation was related to the decrease in H2O2 level by the increase in catalase and peroxidase activities. Moreover, limonene protected the cells to the oxidative stress induced by exogenous addition of H2O2. In view of these results, it is possible that limonene could protect normal lymphocytes from diseases related to oxidative stress, including cancer, but further research is necessary to establish the role of limonene as a potential antioxidant that can effectively protect lymphocytes from oxidative stress and mitochondrial dysfunction. 相似文献