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991.
Jessica Roberts Williams Nina Fredland Hae-Ra Han Jacquelyn C. Campbell Joan E. Kub 《Public health nursing (Boston, Mass.)》2009,26(6):489-499
ABSTRACT Objectives: The purpose of this study was to examine relational aggression and its relationship with adverse psychosocial and physical health symptoms among urban, African American youth.
Design and Sample: Quantitative, cross-sectional survey design.
The sample consisted of 185 predominantly African American (95.1%) seventh-grade students (mean age: 13.0; female: 58%) attending 4 urban middle schools.
Measures: The Children's Social Behavior Scale and Social Experience Questionnaire were used to measure relational aggression and relational victimization. The Pediatric Symptom Checklist was used to assess psychosocial difficulties, including internalizing behaviors, externalizing behaviors, and attention problems. Physical health symptoms were measured with questions about colds/flu, headaches, and stomach aches.
Results: 2-way multivariate analysis of variance revealed significant differences in externalizing behavior, with perpetrators reporting higher levels than nonperpetrators. Victims reported more internalizing behavior than nonvictims; however, this was only significant for males. For females, significant negative effects on health outcomes were found, resulting from the interaction of perpetration and victimization.
Conclusions: Findings suggest that relational aggression is a common occurrence among urban, minority adolescents and may result in adverse health outcomes. These results provide several avenues for future research and implications for healthcare practice. Intervention strategies are needed to prevent relational aggression and continual or subsequent adverse health symptoms. 相似文献
Design and Sample: Quantitative, cross-sectional survey design.
The sample consisted of 185 predominantly African American (95.1%) seventh-grade students (mean age: 13.0; female: 58%) attending 4 urban middle schools.
Measures: The Children's Social Behavior Scale and Social Experience Questionnaire were used to measure relational aggression and relational victimization. The Pediatric Symptom Checklist was used to assess psychosocial difficulties, including internalizing behaviors, externalizing behaviors, and attention problems. Physical health symptoms were measured with questions about colds/flu, headaches, and stomach aches.
Results: 2-way multivariate analysis of variance revealed significant differences in externalizing behavior, with perpetrators reporting higher levels than nonperpetrators. Victims reported more internalizing behavior than nonvictims; however, this was only significant for males. For females, significant negative effects on health outcomes were found, resulting from the interaction of perpetration and victimization.
Conclusions: Findings suggest that relational aggression is a common occurrence among urban, minority adolescents and may result in adverse health outcomes. These results provide several avenues for future research and implications for healthcare practice. Intervention strategies are needed to prevent relational aggression and continual or subsequent adverse health symptoms. 相似文献
992.
Medulloblastoma: from molecular pathology to therapy. 总被引:1,自引:0,他引:1
Alessandra Rossi Valentina Caracciolo Giuseppe Russo Krzysztof Reiss Antonio Giordano 《Clinical cancer research》2008,14(4):971-976
Medulloblastoma is the most common malignant tumor of central nervous system in children. Patients affected by medulloblastoma may be categorized as high-risk and standard-risk patients, based on the clinical criteria and histologic features of the disease. Currently, multimodality treatment, including surgery, radiotherapy, and chemotherapy is considered as the most effective strategy against these malignant cerebellar tumors of the childhood. Despite the potential poor outcomes of these lesions, the 5-year survival stands, at present, at 70% to 80% for standard-risk patients, whereas high-risk patients have a 5-year survival of 55% to 76%. Attempts to further reduce the morbidity and mortality associated with medulloblastoma have been restricted by the toxicity of conventional treatments and the infiltrative nature of the disease. Over the past decade, new discoveries in molecular biology have revealed new insights in signaling pathways regulating medulloblastoma tumor formation. Recent advances in the molecular biology of medulloblastoma indicate that the classification of these embryonal tumors, solely based on histology and clinical criteria, may not be adequate enough. Better understanding of the growth control mechanisms involved in the development and progression of medulloblastoma will allow a better classification, leading to the improvement of the existing therapies, as well as to the development of new therapeutic approaches. 相似文献
993.
Magdalena Esteva Maria Ramos Elena Cabeza Joan Llobera Amador Ruiz Salvador Pita Josep M Segura Jose M Cortés Luis González-Lujan the DECCIRE research group 《BMC cancer》2007,7(1):86
Background
Colorectal cancer (CRC) is the second most frequent tumor in developed countries. Since survival from CRC depends mostly on disease stage at the time of diagnosis, individuals with symptoms or signs suspicious of CRC should be examined without delay. Many factors, however, intervene between symptom onset and diagnosis. This study was designed to: 1) Describe the diagnostic process of CRC from the onset of first symptoms to diagnosis and treatment. 2) Establish the time interval from initial symptoms to diagnosis and treatment, globally and considering patient's and doctors' delay, with the latter due to family physician and/or hospital services. 3) Identify the factors related to defined types of delay. 4) Assess the concordance between information included in primary health care and hospital clinical records regarding onset of first symptoms. 相似文献994.
995.
Minzhong Yu Mary A. Kautz Maria L. Thomas Dagny Johnson Edwin R. Hotchkiss Michael B. Russo 《Ophthalmic & physiological optics》2007,27(2):130-141
Changes in maximal saccadic velocity (SV), initial pupil diameter (IPD), constriction latency (CL) and constriction amplitude (CA) determined by the pupillary light reflex have been found to be sensitive indicators of impairment as a result of drugs, sleepiness, and/or fatigue. Ambient illuminance and time of day are controlled when these indices are applied as repeated measures in fitness-for-duty determinations. The application of oculometrics in unrestricted operational environments, where ambient illuminance and time-of-day testing are not constant, requires understanding of, and potential compensation for, the effects of, and interactions among, these multiple uncontrolled variables. SV, IPD, CL, and CA were evaluated in the morning and evening on two consecutive days following adequate nightly sleep under one baseline ambient illuminance and seven test ambient illuminances. Sixteen healthy volunteers (21-38 years, eight females/eight males) participated. Within and across days, SV was unaffected by decreasing ambient light or time-of-day effects. With the increase of ambient light from 670 to 3300 lx, CL decreased by 1%, while IPD and CA decreased by 17% and 20%, respectively. IPD increased with time of day by 1-10% (IPD was smaller in the morning). The results show that SV and CL are essentially resistant to changes in ambient light and time-of-day effects, simplifying their application in uncontrolled operational environments. 相似文献
996.
João Luiz Quagliotti Durigan Thiago Luiz Russo Juliana Uema Ribeiro Heloisa Sobreiro Selistre-de-Araujo Tania Fátima Salvini 《Toxicon》2008,52(6):687-694
This study evaluated the effects of alternagin-C (ALT-C) on mRNA levels of VEGF, MyoD and matrix metalloproteinase 2 (MMP-2) and on activity of MMPs in injured tibialis anterior (TA) muscle induced by cryolesioning in rats. Thirty-six Wistar rats (3 months old, 258.9 ± 27 g) were divided into five groups: (1) control group; (2) injured TA and analyzed 3 days later; (3) injured TA treated with ALT-C and analyzed 3 days later; (4) injured TA and analyzed 7 days later and (5) injured TA treated with ALT-C and analyzed 7 days later. The injured muscle received 25 μl of ALT-C (50 nM). The injured and uninjured muscle areas were quantified by light microscopy. The MMP activity was evaluated through zymography, and mRNA of MyoD, VEGF and MMP-2 was assessed by quantitative polymerase chain reaction. ALT-C neither reduced the muscle injury area nor altered the pattern of MyoD and VEGF expression in injured muscles. However, ALT-C reduces both MMP-2 mRNA and gelatinolytic activity in injured muscles. The study indicates that ALT-C, at the tested concentrations, did not improve muscle regeneration process in rats. The effect on MMP-2 mRNA and gelatinolytic activity suggests that ALT-C changes the overall balance of ECM protein turnover during muscle regeneration. 相似文献
997.
998.
Background
To determine differences among persons who provided blood specimens for HIV testing compared with those who did not among those interviewed for the population-based Zimbabwe Young Adult Survey (YAS). 相似文献999.
1000.
Stephane Supiot Shubber Shubbar Neil Fleshner Padraig Warde Karen Hersey Kris Wallace Heather Cole Joan Sweet John Tsihlias Michael A.S. Jewett Laurence Klotz Robert G. Bristow 《Radiotherapy and oncology》2008,88(1):53-60
BACKGROUND AND PURPOSE: Selected patients undergoing radical prostatectomy for localized prostate cancer can be at high-risk for pT3 disease and require subsequent radiotherapy. In a phase I trial, we investigated the feasibility of pre-operative radiotherapy for this patient subset. MATERIALS AND METHODS: Eligibility criteria were: T1/T2N0M0 tumors plus (i) Gleason >or=7, PSA>10 ng/ml and <35 ng/ml, or (ii), PSA >15 ng/ml and less <35 ng/ml (any Gleason). Patients received 25 Gy in five fractions of radiotherapy followed by radical prostatectomy. Trial endpoints included intra-operative morbidity and late toxicity following combined treatment. We also stained pre- and post-radiotherapy prostate samples for DNA damage response proteins. RESULTS: Between 2001 and 2004, 15 patients were entered on trial. Thirteen patients completed combined-modality treatment. Only one patient had signs of intra-operative inflammation. No patient had post-operative complication. There was no severe late gastrointestinal toxicity. Late genitourinary toxicity consisted of severe urinary incontinence in 2 of 13 patients. From a translational standpoint, irradiated prostate tumor tissues had long-term activation of the CDK-inhibitor p21(WAF) associated with reduced cell proliferation. CONCLUSION: Intra-operative morbidity is low following short-course, pre-operative radiotherapy. A phase II trial is planned to fully document biochemical response with this combined-modality approach. 相似文献