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941.
Background
Filipino Americans are the fastest growing Asian minority group in the United States. There is limited knowledge about their breast cancer knowledge, screening practices and attitudes. 相似文献942.
The distal end of the ulna is an uncommon site for primary bone tumours. We report the case of a 23-year-old male, with a giant-cell tumour of the distal end of the ulna treated with en-bloc resection and stabilisation of the ulnar stump using one half of the extensor carpi ulnaris tendon. The amount of bone removed from the distal end of the ulna was 9.0 centimeters long. The functional and oncological results were excellent. Stabilisation of the ulnar stump, using one half of the extensor carpi ulnaris tendon, has been described by Goldner and Hayes in 1979, after resection of a relatively small segment of the distal ulna. This is the first report on this technique for stabilisation of the ulnar stump after resection of a large distal ulnar segment. A literature review of reported cases with a resection of the distal ulna for primary bone tumours is presented. The available data are inconclusive as to whether a simple excision is adequate or a reconstruction/stabilisation is required. 相似文献
943.
Paparrigopoulos T Melissaki A Tsekou H Efthymiou A Kribeni G Baziotis N Geronikola X 《Brain injury : [BI]》2006,20(8):873-878
Primary objective: To investigate the circadian rhythm of serum melatonin in patients with traumatic brain injury (TBI) during Intensive Care Unit (ICU) stay and its relationship with core body temperature fluctuations and measures of severity of their condition.
Methods and procedures: The pilot study was conducted in the ICU of a general hospital in Athens, Greece. Blood melatonin was determined in eight patients consecutively admitted at the ICU following severe head injury, eight times per day during the first and second day following admission. Core body temperature was recorded at hourly intervals. Patients were also assessed with the Glasgow Coma Score (GCS) and the APACHE II score.
Results: Melatonin concentrations were lower than the normally reported values. Mean night-time melatonin levels were higher than mean daytime levels both on the first and second days, although not statistically significant. Diurnal variation of melatonin was associated with the GCS. Thus, patients with low GCS (n = 4) did not exhibit a consistent diurnal variation of melatonin, whereas those with high GCS (n = 4) retained the normally expected fluctuations.
Conclusions: ICU-treated TBI patients exhibit reduced melatonin levels and a circadian secretion profile which is related to the severity of the injury. Patients with more severe head trauma exhibit a clearly disrupted pattern of melatonin secretion, whereas those with less severe trauma preserve a relatively intact diurnal rhythm. Furthermore, the diurnal secretion pattern of melatonin appeared to be dissociated from the circadian rhythm of core body temperature. These preliminary findings may have implications for the management of TBI patients. 相似文献
Methods and procedures: The pilot study was conducted in the ICU of a general hospital in Athens, Greece. Blood melatonin was determined in eight patients consecutively admitted at the ICU following severe head injury, eight times per day during the first and second day following admission. Core body temperature was recorded at hourly intervals. Patients were also assessed with the Glasgow Coma Score (GCS) and the APACHE II score.
Results: Melatonin concentrations were lower than the normally reported values. Mean night-time melatonin levels were higher than mean daytime levels both on the first and second days, although not statistically significant. Diurnal variation of melatonin was associated with the GCS. Thus, patients with low GCS (n = 4) did not exhibit a consistent diurnal variation of melatonin, whereas those with high GCS (n = 4) retained the normally expected fluctuations.
Conclusions: ICU-treated TBI patients exhibit reduced melatonin levels and a circadian secretion profile which is related to the severity of the injury. Patients with more severe head trauma exhibit a clearly disrupted pattern of melatonin secretion, whereas those with less severe trauma preserve a relatively intact diurnal rhythm. Furthermore, the diurnal secretion pattern of melatonin appeared to be dissociated from the circadian rhythm of core body temperature. These preliminary findings may have implications for the management of TBI patients. 相似文献
944.
Diabetes results from an inadequate mass of functional beta-cells. Such inadequacy could result from loss of beta-cells due to an immune assault or the inability to compensate for insulin resistance. Thus, mechanisms that regulate the number of beta-cells will be key to understanding both the pathogenesis of diabetes and for developing therapies. In this study, we show that cell cycle regulator p27 plays a crucial role in establishing the number of beta-cells formed before birth. We show that p27 accumulates in terminally differentiated beta-cells during embryogenesis. Disabling p27 allows newly differentiated beta-cells that are normally quiescent during embryogenesis to reenter the cell cycle and proliferate. As a consequence, excess beta-cells are generated in the p27(-/-) mice, doubling their beta-cell mass at birth. The early postnatal expansion of beta-cell mass was unaffected in p27(-/-) mice, indicating that the main function of p27 is to maintain the quiescent state of newly differentiated beta-cells generated during embryogenesis. The expanded beta-cell mass was accompanied by increased insulin secretion; however, the p27(-/-) mice were glucose intolerant, as these mice were insulin insensitive. To assess the role of p27 to affect regeneration of beta-cells in models of diabetes, p27(-/-) mice were injected with streptozotocin (STZ). In contrast to control mice that displayed elevated blood glucose levels, p27(-/-) mice showed decreased susceptibility to develop STZ-induced diabetes. Furthermore, beta-cells retained the ability to reenter the cell cycle at a far greater frequency in p27(-/-) mice after developing STZ-induced diabetes compared with wild-type littermates. These data indicate that p27 is a key regulator in establishing beta-cell mass and an important target for facilitating beta-cell regeneration in therapies for diabetes. 相似文献
945.
Meta-analysis to investigate the joint effect of multiple factors in the aetiology of a disease is of increasing importance in epidemiology. This task is often challenging in practice, because studies typically concentrate on studying the effect of only one exposure, sometimes may report the interaction between two exposures, but rarely address more complex interactions that involve more than two exposures. In this paper, we develop a meta-analysis framework that combines estimates from studies of multiple exposures. A key development is an approach to combining results from studies that report information on any subset or combination of the full set of exposures. The model requires assumptions to be made about the prevalence of the specific exposures. We discuss several possible model specifications and prior distributions, including information internal and external to the meta-analysis data set, and using fixed-effect and random-effects meta-analysis assumptions. The methodology is implemented in an original meta-analysis of studies relating the risk of bladder cancer to two N-acetyltransferase genes, NAT1 and NAT2, and smoking status. 相似文献
946.
Parenting is a transactional process, influenced by the child’s behavior and the environmental context. The present study
explores the beliefs and practices of parents of aggressive and oppositional adolescents to understand better the relation
among parenting practices, context, and youth violence. Parents of juvenile offenders (N=203) completed assessments of youths’ violent and oppositional behaviors, community violence exposure, and their own beliefs
and parenting behaviors and perceptions of the juvenile justice system. Parents of youth with the highest levels of violent
and oppositional behavior problems reported elevated feelings of hopelessness regarding the child’s future, inadequacy as
a parent, fear of physical harm by the child, anger toward the child, as well as difficulty monitoring the child. All parents
reported relatively high levels of perceived support by the justice system. Parental stress was also examined as a possible
influence on the parents’ beliefs and behaviors regarding the child. Results suggest that parents’ emotional and behavioral
responses should be addressed when intervening with juvenile offenders.
Editors’ Strategic Implications: The authors present evidence to suggest that parents’ perceptions of hopelessness/inadequacy and their fear for their child’s
safety are both by-products of life with an aggressive child as well as contributing factors to that aggressive behavior.
Thus, successful interventions must both target the parents as change agents in the youth’s life but also include a strong
parental support component, so that parents will have an opportunity to orchestrate positive impacts in high-risk environments. 相似文献
947.
OBJECTIVE: To characterize physical activity levels of adults with mental retardation and identify limitations in published research. DATA SOURCES: Key word searches for "mental retardation," "intellectual disability," "learning disability," or "developmental disability" combined with "physical activity" or "habitual exercise" identified articles from MEDLINE, Academic Search Elite, Psych Articles, Health Source, and SPORT Discus. This produced a total of 801 citations. STUDY INCLUSION AND EXCLUSION CRITERIA: Published English-language literature that quantitatively measured physical activity levels of adults with mental retardation was included in this review. Fourteen articles met this criterion. DATA EXTRACTION: Characteristics of participants, study design, outcome measures, methods of analyses, and findings in terms of percentages, step counts, and accelerometer output were extracted. DATA SYNTHESIS: Data were synthesized to identify the percentage of adults with mental retardation who met published health-related physical activity criteria and compare them with adults without mental retardation and to examine study limitations. RESULTS: The studies with the greatest rigor indicate that one-third of adults or fewer with mental retardation were sufficiently active to achieve health benefits. However, data are insufficient to determine whether adults with mental retardation are less active than the general community. CONCLUSIONS: Future research would be enhanced by including appropriately powered representative samples, by including comparison groups, by validating physical activity questionnaires, and by determining the accuracy of proxy respondents. 相似文献
948.
The objectives of this study were to identify the factors limiting the absorption of purified lycopene after oral administration, and to comparatively assess plasma data sets after single oral and intravenous administrations in dogs to define the conditions for performing an absolute bioavailability study. Solubility of purified lycopene (all-trans, 93.5%) was determined in media simulating the conditions in the fasted and in the fed upper gastrointestinal lumen. After evaluating the plasma levels achieved following single administrations of purified lycopene powder to fasted and fed dogs at escalating doses (75-750 mg), a crossover study was performed in four fed female mongrel dogs at two phases. In phase I, one soft gelatine capsule (10 mg lycopene) with 500 mL milk was administered orally. In phase II, 500 mL milk was administered orally and 250 mL 5% dextrose containing 5 mg lycopene in the form of a binary system with hydroxypropyl-beta-cyclodextrin (HP-beta-CyD) was administered intravenously over 3.5 h. In-vitro and preliminary canine studies confirmed that, after oral administration of lycopene in solid form, arrival of lycopene into the systemic circulation was limited by lymphatic transport and, in addition, if the administered dose was higher than approximately 2 mg, by intralumenal solubility. During the first 50 h after single administrations to fed dogs, lycopene plasma levels were lower after intravenous than after oral administration. This could have been related to capacity limited elimination of lycopene and/or route-dependent disposition kinetics. Estimation of the amount of lycopene reaching the systemic circulation after oral and after intravenous administration requires separate estimations of total body clearance of lycopene. 相似文献
949.
Rapidis AD Trichas M Stavrinidis E Roupakia A Ioannidou G Kritselis G Liossi P Giannakouras G Douzinas EE Katsilieris I 《Oral oncology》2006,42(7):675-684
Encouraging results have recently been reported in patients (pts) with locally advanced unresectable squamous cell carcinoma of the head and neck (SCCHN) when induction chemotherapy (IC) is used and followed by radiotherapy (RT). The present study assessed the therapeutic response of an aggressive regimen consisting of docetaxel (TXT), cisplatin (CDDP) and 5-fluorouracil (5-Fu) as IC and concurrent with RT in pts with locally advanced (stages III and IV) SCCHN. 42 pts (35 male and 7 female) with a mean age of 58 years suffering from stages III and IV (Mo) SCCHN were included to this organ preservation phase II clinical trial. The site of the primary tumors was the anterior mouth in 9 pts, base of tongue and oropharynx in 12, middle third of the face in 8 and larynx in 13. The performance status of the pts was 0-1 according to WHO and above 80% according to Karnofsky classification. IC consisted of TXT (40 mg/m2), CDDP (40 mg/m2) and 5-Fu (350 mg/m2) every two weeks (wks) for a total of four courses and repeated, coupled with RT (66-68 cGys total dose fractionated at 200 Gy per day, 5 days a week), for up to seven wks. In total, pts received eight courses of chemotherapy (CT) at the end of RT treatment. Pts were evaluated at the end of IC, after RT and every six wks thereafter. 41 pts were eligible for evaluation after IC (one died from myocardial infarction) and 39 after completion of treatment (two died during RT). Statistical multivariate analysis was performed using SPSS (11) package. Complications from IC and RT were evaluated according to WHO criteria and included mucositis Grade (Gr) IV in 10% of the pts, Gr III in 50%, Gr II in 20%. Anemia presented in 40% of the pts with Gr II, 40% with Gr I, neutropenia 17% with Gr IV, 20% with Gr III, 30% with Gr II, thrombocytopenia 3% with Gr III, 10% with Gr I and xerostomia up to Gr II in 70% of the pts. The response rate (RR) after IC was complete response (CR) for 10 pts (24.4%), partial response (PR) for 22 (53.7%) and no response (NR) for 9 (21.9%). At the end of the treatment the RR in the intention-to-treat population were CR for 25 pts (64.1%), and PR for 14 (35.9%). Follow up ranges from 18 to 56 months (mts). 14 pts died during follow-up time. The mean survival time is 41 mts and the median 40. 2 pts with CR developed local recurrence and two distant metastases, whereas all pts with PR developed progressive disease (PD) and all but two are dead from disease. It is evident from this phase II study that TXT-CDDP-5Fu based IC followed by the same regimen coupled with RT improves local control. Pts that showed CR after IC continued to maintain disease status during RT (P-value=0.0181). In pts with SD concurrent RT did not alter dramatically disease outcome. Patients who showed complete response after both IC and RT presented a four-year survival rate of 74% compared to a 30% to partial responders (P-value=0.0001). Results are encouraging and further study of the toxicity and follow-up is needed to validate treatment effectiveness. 相似文献
950.
Rosa Lapalombella Xiaobin Zhao Georgia Triantafillou Bo Yu Yan Jin Gerard Lozanski Carolyn Cheney Nyla Heerema David Jarjoura Amy Lehman L James Lee Guido Marcucci Robert J Lee Michael A Caligiuri Natarajan Muthusamy John C Byrd 《Clinical cancer research》2008,14(2):569-578
PURPOSE: To date, efforts to study CD52-targeted therapies, such as alemtuzumab, have been limited due to the lack of stable CD52 expressing transformed B-cell lines and animal models. We describe generation and utilization of cell lines that stably express CD52 both in vitro and in vivo. EXPERIMENTAL DESIGN: By limiting dilution, we have established several clones of Raji-Burkitt's lymphoma cell line that express surface CD52. Immunophenotype and cytogenetic characterization of these clones was done. In vivo usefulness of the CD52(high) cell line to evaluate the therapeutic efficacy of CD52-directed antibody was investigated using a SCID mouse xenograft model. RESULTS: Stable expression of CD52 was confirmed in cells cultured in vitro up to 52 weeks of continuous growth. The functional integrity of the expressed CD52 molecule was shown using alemtuzumab, which induced cytotoxic effects in vitro in the CD52(high) but not the CD52(low) clone. Compared with control antibody, alemtuzumab treatment in CD52(high) inoculated mice resulted in significantly increased median survival. Comparable levels of CD52-targeted direct cytotoxicity, complement-dependent cytotoxicity, and antibody-dependent cytotoxicity and anti-CD52 immunoliposome-mediated delivery of synthetic oligodeoxyribo nucleotides in CD52(high) clone and primary B-chronic lymphocytic leukemia cells implicated potential in vivo application of this model for evaluation of CD52-targeted antibody and immunoliposomes encapsulating therapeutic agents. CONCLUSIONS: These results show the in vitro utility of the cloned Raji cell lines that stably express high levels CD52. The disseminated leukemia-lymphoma mouse model described herein using these stable cell lines can serve as an excellent system for in vivo therapeutic and mechanistic evaluation of existing and novel antibodies directed against CD52 molecule. 相似文献