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51.
The SmoA1 mouse model reveals that notch signaling is critical for the growth and survival of sonic hedgehog-induced medulloblastomas 总被引:20,自引:0,他引:20
Hallahan AR Pritchard JI Hansen S Benson M Stoeck J Hatton BA Russell TL Ellenbogen RG Bernstein ID Beachy PA Olson JM 《Cancer research》2004,64(21):7794-7800
52.
Dementia Care Mapping reconsidered: exploring the reliability and validity of the observational tool
BACKGROUND: Dementia Care Mapping (DCM) is a widely used observational method for evaluating the service quality provided to people with dementia. However, there is little evidence concerning its reliability and validity when used by routine care staff for whom it was designed. METHOD: The study evaluated levels of inter-observer agreement; The ability of the five-minute time frame to reflect the 'actual passing of time'; And the nature of the relationship between individual Well/Ill-Being values (WIB) and dependency levels.Data collected using DCM and continuous time sampling (CTS) were compared. The methods were used in parallel where the CTS coder and the DCM mapper(s) observed the same participants.Observations were carried out with 64 people with dementia within a day hospital and a continuing care ward. Inter-observer agreement was calculated across 20 participants.Dependency levels were measured using the Clifton Assessment Procedure for the Elderly (CAPE) (Pattie and Gilleard, 1979). RESULTS: Low levels of inter-observer agreement were found where 11 of the 25 Behaviour Category codes and all six Well/Ill-being Codes produced unacceptable kappas (<0.6).The Behaviour coding frame provided a meaningful picture of activities participants engaged in, but significantly underestimated participant levels of inactivity.A strong relationship was demonstrated between participants' WIB score and levels of dependency, thus DCM was unable to measure well-/ill-being as a separate construct from participants' levels of dependency. CONCLUSIONS: Questions were raised regarding the reliability and validity of DCM as used by routine care staff. Possible reasons for this, and suggestions for amendments are made. 相似文献
53.
Using continuous time sampling and direct observation methodology, this study examined the impact of social interaction in music listening on behavioural responses of people with moderate-to-severe dementia (n = 24). Using Kitwood's theory of personhood as a framework, it was hypothesized that levels of well-being and engagement would be greatest during a live music condition compared with recorded and no music conditions and that levels of challenging behaviour would decrease most in the live music conditions compared with the other music conditions. The relationship between severity of cognitive impairment and well-being, engagement and challenging behaviours across conditions was also examined. The findings suggest that live music was significantly more effective in increasing levels of engagement and well-being regardless of level of cognitive impairment. No significant differences across conditions were found for challenging behaviours, but the correlation between these and cognitive impairment revealed mixed results. Clinical implications regarding the use of live music in dementia care settings are highlighted and recommendations for future research of interventions aimed at reducing challenging behaviours are discussed. 相似文献
54.
Symons FJ Clark RD Hatton DD Skinner M Bailey DB 《American journal of medical genetics. Part A》2003,(2):115-121
In this study, we distributed surveys to 67 families of young boys with fragile X syndrome to determine the prevalence, onset, form, function, location, and correlates of self-injurious behavior. Fifty-five surveys were completed (82%). The mean age of the boys at the time of the survey was 80 months (range = 20-144). Self-injurious behavior (SIB) was reported for 58% of the participants with a mean age of onset of 31 months. The mean number of forms of self-injury was 2 per participant. Biting was the most commonly reported form of self-injury with the fingers and back of the hand disproportionately targeted as the most prevalent self-injury body site. There was no linear increase in risk of SIB with age past 25 months. SIB was reported as most likely to occur following the presentation of difficult task demands or changes in routine. Significant group differences were found between overall ratings of problem behavior for boys with self-injury compared to those without self-injury. Groups did not differ on measures of fragile X mental retardation protein (FMRP), autism status, adaptive behavior, or age first medicated. Results are discussed in terms of future research designed to further elucidate the behavioral phenotype of fragile X syndrome. 相似文献
55.
Background: Carbon isotope ratio methods are used in doping control to determine whether urinary steroids are endogenous or pharmaceutical. METHODS: Gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) was used to determine the delta(13)C values for 5 beta-androstane-3 alpha,17 beta-diyl diacetate (5 beta A), 5 alpha-androstane-3 alpha,17 beta-diyl diacetate (5 alpha A), and 5 beta-pregnane-3 alpha,20 alpha-diyl diacetate (5 beta P) in a control group of 73 healthy males and 6 athletes with testosterone/epitestosterone ratios (T/E) >6. RESULTS: The within-assay precision SDs for 5 beta A, 5 alpha A, and 5 beta P were +/- 0.27 per thousand, +/- 0.38 per thousand, and +/- 0.28 per thousand, respectively. The between-assay precision SDs ranged from +/- 0.40 per thousand to +/- 0.52 per thousand. The system suitability and batch acceptance scheme is based on SDs. For the control group, the mean delta(13)C (SD) values were -25.69 per thousand (+/- 0.92 per thousand), -26.35 per thousand (+/- 0.68 per thousand), and -24.26 per thousand (+/- 0.70 per thousand), for 5 beta A, 5 alpha A, and 5 beta P, respectively. 5 beta P was greater than 5 beta A and 5 alpha A (P <0.01), and 5 beta A was greater than 5 alpha A (P <0.01). The means - 3 SD were -28.46 per thousand, -28.39 per thousand, and -26.37 per thousand for 5 beta A, 5 alpha A, and 5 beta P, respectively. The maximum difference between 5 beta P and 5 beta A was 3.2 per thousand, and the maximum 5 beta A/5 beta P was 1.13. Three athletes with chronically elevated T/Es had delta(13)C values consistent with testosterone administration and three did not. CONCLUSIONS: This GC-C-IRMS assay of urine diols has low within- and between-assay SDs; therefore, analysis of one urine sample suffices for doping control. The means, SDs, +/-3 SDs, and ranges of delta(13)C values in a control group are established. In comparison, testosterone users have low 5 beta A and 5 alpha A, large differences between 5 beta A or 5 alpha A and 5 beta P, and high 5 beta A/5 beta P and 5 alpha A/5 beta P ratios. 相似文献
56.
PURPOSE: To describe the demographics, etiologic factors, clinical presentations, and outcomes of orbital fractures in children. METHODS: This was a retrospective case series of 96 consecutive patients under 18 years of age with orbital fractures presenting to the Massachusetts Eye and Ear Infirmary, including both hospitalized and nonhospitalized patients. RESULTS: Orbital fractures in children were most frequently the result of sports, assault, or motor vehicle accident. The majority of patients did not require hospitalization and were treated as outpatients. The medial wall and floor of the orbit were the most frequent locations of fracture. Approximately half of the patients in this series required surgery, most often for entrapment. There were no cases of persistent diplopia in patients in whom surgery was performed or was not indicated. Associated ocular injuries were observed in half of the patients. CONCLUSIONS: In this series of hospitalized and nonhospitalized patients, orbital fractures in children had a location pattern similar to that most frequently observed in adult patients (floor and medial wall). Orbital fractures in children frequently require surgery. The high prevalence of ocular injury in children with orbital fractures emphasizes the need for a comprehensive ophthalmic evaluation. 相似文献
57.
Vauzelle-Kervroëdan F Delcourt C Forhan A Jougla E Hatton F Papoz L 《Diabetes & metabolism》1999,25(5):404-411
This study was implemented in France to determine the causes of death in diabetic patients, whether diabetes was mentioned or not on the death certificate, and to assess the underestimation of the prevalence of diabetes at death. Two stratified random samples of death certificates were selected in the national mortality data base. The first included certificates mentioning diabetes as a cause of death (cases). The second, included certificates with no mention of diabetes (controls). For each certificate, a record form was sent to the certifying physician to ascertain diabetes in the first group and to trace unrecorded diabetes in the second group. In case of diabetes, the characteristics of the patient and his disease were collected (age at onset, treatment, complications ...). We obtained complete data for 325 cases and 959 controls. Among cases, 1% of the subjects were not confirmed as diabetic, while almost 10% of the controls were identified as having diabetes. The corresponding ratio of the corrected prevalence at death to that provided by the French statistics was estimated to 4.0 in men and 3.1 in women. Particular features are that 2% of the total diabetic decedents died from acute metabolic complications (diabetic or hyperosmolar coma, acidoketosis, or acute hypoglycemia), and that 33% of the unreported diabetic decedents under 45 died from trauma or poisoning. These results show that in France, the death rates published in the statistics for diabetes dramatically underestimate the impact of diabetes. A high risk of death is linked to this disease, particularly in people aged under 45, a problem that health deciders should address. 相似文献
58.
B7-1和IL-12基因转染对肝癌细胞免疫原性的影响 总被引:1,自引:1,他引:1
目的 观察B7-1和IL-12基因表达对人肝癌细胞免疫原性原影响。方法 分别将B7-1和IL-12基因以逆转录病毒介导转染HepG2细胞。阳性克隆细胞与健康人外周血淋巴细胞(PBL)混合培养后,用流式细胞仪检测PBL表面Ⅰ类人白细胞抗原(HLA-Ⅰ)分子表达,以MTT法检测PBL的特异性杀伤活性K562细胞的活性。结果 混合HepG2/B7-1HepG2/IL-12细胞组PBL表面的HLA-Ⅰ分子 相似文献
59.
Linda T. Li Nutan B. Hebballi Eric W. Reynolds Seyed A. Arshad Gabrielle E. Hatton Dalya M. Ferguson Mary T. Austin Kevin P. Lally Kuojen Tsao 《Journal of pediatric surgery》2021,56(7):1113-1116
PurposeRepetitive painful stimuli and early exposure to opioids places neonates at risk for neurocognitive delays. We aimed to understand opioid utilization for neonates with gastroschisis.MethodsWe performed a retrospective review of infants with gastroschisis at a tertiary children's hospital (2017–2019). Multivariate linear regression was performed to analyze variations in opioid use.ResultsAmong 30 patients with gastroschisis, 33% were managed by primary suture-less closure, 7% by primary sutured closure, 40% by spring silo, and 20% by handsewn silo. The proportion of pain medication used was: morphine (89%), acetaminophen (8%), and fentanyl (3%). Opioids were used for a median of 6.5 days (range 0–20) per patient. Median total opioid administered across all patients was 2.2 morphine milligram equivalents (MME)/kg (IQR 0.7–3.3). Following definitive closure, median opioid use was 0.2 MME/kg (IQR 0.1–0.8). With multivariate regression, 45% of the variation in MME use was associated with the type of surgery after adjusting for weight, gestational age, and gender, p = 0.02. After definitive fascial closure, there was no significant variations in opioid use.ConclusionThere is a significant variation in the utilization of opioid, primarily prior to fascial closure. Understanding pain needs and standardization may improve opioid stewardship in infants with gastroschisis. 197/200Level of EvidenceLevel III 相似文献
60.
Benjamin Hatton Lidiya Mishchenko Stan Davis Kenneth H. Sandhage Joanna Aizenberg 《Proceedings of the National Academy of Sciences of the United States of America》2010,107(23):10354-10359
Whereas considerable interest exists in self-assembly of well-ordered, porous “inverse opal” structures for optical, electronic, and (bio)chemical applications, uncontrolled defect formation has limited the scale-up and practicality of such approaches. Here we demonstrate a new method for assembling highly ordered, crack-free inverse opal films over a centimeter scale. Multilayered composite colloidal crystal films have been generated via evaporative deposition of polymeric colloidal spheres suspended within a hydrolyzed silicate sol-gel precursor solution. The coassembly of a sacrificial colloidal template with a matrix material avoids the need for liquid infiltration into the preassembled colloidal crystal and minimizes the associated cracking and inhomogeneities of the resulting inverse opal films. We discuss the underlying mechanisms that may account for the formation of large-area defect-free films, their unique preferential growth along the 〈110〉 direction and unusual fracture behavior. We demonstrate that this coassembly approach allows the fabrication of hierarchical structures not achievable by conventional methods, such as multilayered films and deposition onto patterned or curved surfaces. These robust SiO2 inverse opals can be transformed into various materials that retain the morphology and order of the original films, as exemplified by the reactive conversion into Si or TiO2 replicas. We show that colloidal coassembly is available for a range of organometallic sol-gel and polymer matrix precursors, and represents a simple, low-cost, scalable method for generating high-quality, chemically tailorable inverse opal films for a variety of applications. 相似文献