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151.
OBJECTIVE: This study investigated whether there is a bias against eating disorders research among the leading psychiatric, psychological, and medical journals. METHOD: The authors performed a comparison between the number of empirical articles published about anorexia nervosa and/or bulimia nervosa and the number of articles published about panic disorder and/or agoraphobia (i.e., disorders of comparable disease burden) in 29 high-impact journals over a 5-year period (1996-2001). RESULTS: There were almost twice as many published empirical articles about panic disorder and/or agoraphobia (N=365) as there were about anorexia nervosa and/or bulimia nervosa (N=169). CONCLUSIONS: The findings indicate a possible bias against eating disorders research among some leading psychiatric journals. Alternative explanations and implications are discussed. 相似文献
152.
Effect of a multidisciplinary amyotrophic lateral sclerosis (ALS) clinic on ALS survival: a population based study, 1996-2000 总被引:1,自引:0,他引:1 下载免费PDF全文
Traynor BJ Alexander M Corr B Frost E Hardiman O 《Journal of neurology, neurosurgery, and psychiatry》2003,74(9):1258-1261
BACKGROUND: In recent years, there has been a paradigm shift in the method of healthcare delivery to amyotrophic lateral sclerosis (ALS) patients with the emergence of multidisciplinary ALS clinics that cater exclusively for patients with this condition. The impact of multidisciplinary management has not been previously evaluated. METHODS: Using data from the Irish ALS Register, we conducted a prospective, population based study of all ALS cases diagnosed in Ireland over a five year period to evaluate the effectiveness of a multidisciplinary clinic on ALS survival. RESULTS: Eighty two (24%) patients attended the multidisciplinary ALS clinic, with the remaining 262 (76%) cases followed in a general neurology clinic. The ALS clinic cohort was an average of five years younger (60.1 v 65.6 years) and were more likely to receive riluzole than the general neurology cohort (99% v 61%). The median survival of the ALS clinic cohort was 7.5 months longer than for patients in the general neurology cohort (logrank = 15.4, p < 0.0001). Overall, one year mortality was decreased by 29.7%. Prognosis of bulbar onset patients was extended by 9.6 months if they attended the ALS clinic. Using multivariate analysis, attendance at the ALS clinic was an independent covariate of survival (HR = 1.47, p = 0.02). CONCLUSIONS: ALS patients who received their care at a multidisciplinary clinic had a better prognosis than patients attending a general neurology clinic. The data suggest that active and aggressive management enhances survival, particularly among ALS patients with bulbar dysfunction. The effect of clinic type must be considered in future clinical trials design. 相似文献
153.
PET imaging of brain acetylcholinesterase using [11C]CP-126,998, a brain selective enzyme inhibitor 总被引:1,自引:0,他引:1
Bencherif B Endres CJ Musachio JL Villalobos A Hilton J Scheffel U Dannals RF Williams S Frost JJ 《Synapse (New York, N.Y.)》2002,45(1):1-9
PET and [(11)C]CP-126,998, an N-benzylpiperidinebenzisoxazole, were used to image brain acetylcholinesterase (AChE) distribution in healthy controls before and after administration of 5 mg donepezil p.o., a reversible AChE inhibitor. Logan plots were used to compute distribution volumes (V(T)). The V(T) of [(11)C]CP-126,998 was highest in the basal ganglia and cerebellum and lowest in the cerebral cortex, thalamus, amygdala, and hippocampus. The regional V(T) values correlated well with AChE concentration measured in vitro. Donepezil, given 4 h before PET scanning, induced a substantial inhibition of [(11)C]CP-126,998 binding (43-62%) in all brain regions when compared to the baseline PET study. The results of this study indicate that PET imaging of [(11)C]CP-126,998 may be useful in quantifying the distribution of regional brain AChE. This new PET radiotracer may potentially be employed in the diagnosis and treatment of patients with disorders of cholinergic neurotransmission, such as Alzheimer's disease. 相似文献
154.
Talley LI Grizzle WE Waterbor JW Brown D Weiss H Frost AR 《International journal of cancer. Journal international du cancer》2002,98(1):118-127
Breast cancers in younger, premenopausal women are more likely to exhibit an adverse prognostic profile (including negative steroid hormone receptors and a high rate of cellular proliferation) and poor outcome than breast cancers in postmenopausal women. It has been hypothesized that this adverse prognostic profile is a result of the higher histologic grade of breast cancers in pre- compared with post-menopausal women. To assess the association of expression of steroid hormone receptors and indicators of proliferation while controlling for histologic grade, we identified 100 infiltrating ductal carcinomas from premenopausal women 45 years of age or younger and 100 from postmenopausal women 65 years of age or older. The carcinomas were selected so that the histologic grades (low versus high) were distributed equally between the 2 groups. Estrogen receptors (ER), progesterone receptors (PR), p27(Kip1) and Ki-67 (to measure rate of proliferation) were assessed by immunohistochemistry and compared between groups. Clinical information and survival data were also analyzed. ER content was lower and proliferation was higher in carcinomas in premenopausal women (p = 0.048 and p = 0.005, respectively). By univariate analysis, p27(Kip1) and PR were not different between the groups; however, in multivariate analysis, p27(Kip1) was higher in postmenopausal women, but only in a subgroup with highly proliferative carcinomas. Overall survival was similar in the pre- and postmenopausal women. Furthermore, low p27(Kip1) and African-American ethnicity predicted a poorer overall survival in the premenopausal, but not in the postmenopausal, women in our study. After controlling for histologic grade, a lower expression of ER and a higher proliferative index were detected in breast carcinomas in premenopausal women. Therefore, some prognostic indicators, such as ER and proliferative rate, may be more closely associated with menopausal status than histologic grade. Our data also suggest that some prognostic factors are not equally effective as predictors of survival in pre- and postmenopausal women. 相似文献
155.
Simonneau G Barst RJ Galie N Naeije R Rich S Bourge RC Keogh A Oudiz R Frost A Blackburn SD Crow JW Rubin LJ;Treprostinil Study Group 《American journal of respiratory and critical care medicine》2002,165(6):800-804
Pulmonary arterial hypertension is a life-threatening disease for which continuous intravenous prostacyclin has proven to be effective. However, this treatment requires a permanent central venous catheter with the associated risk of serious complications such as sepsis, thromboembolism, or syncope. Treprostinil, a stable prostacyclin analogue, can be administered by a continuous subcutaneous infusion, avoiding these risks. We conducted a 12-week, double-blind, placebo-controlled multicenter trial in 470 patients with pulmonary arterial hypertension, either primary or associated with connective tissue disease or congenital systemic-to-pulmonary shunts. Exercise capacity improved with treprostinil and was unchanged with placebo; the between treatment group difference in median six-minute walking distance was 16 m (p = 0.006). Improvement in exercise capacity was greater in the sicker patients and was dose-related, but independent of disease etiology. Concomitantly, treprostinil significantly improved indices of dyspnea, signs and symptoms of pulmonary hypertension, and hemodynamics. The most common side effect attributed to treprostinil was infusion site pain (85%) leading to premature discontinuation from the study in 8% of patients. Three patients in the treprostinil treatment group presented with an episode of gastrointestinal hemorrhage. We conclude that chronic subcutaneous infusion of treprostinil is an effective treatment with an acceptable safety profile in patients with pulmonary arterial hypertension. 相似文献
156.
AIM: To investigate the effect of eating in a supervised dining room, on nutritional intake and weight, for elderly patients on an acute medicine for the elderly ward. METHOD: Patients on the intervention ward were encouraged to attend a dining room every lunch time by a trained nursing assistant as part of the rehabilitation process. The patients on the control ward ate only by their bedside. Food intake and weight data were collected over the study period on each patient. RESULTS: Forty-eight patients participated in the study. At the lunch time meal studied the dining room group had higher intakes of energy compared with the controls [489 kcal (95% CI: 438-554) versus 360 kcal (95% CI: 289-448), P < 0.013]. There was no difference in protein intake between the groups [18.9 g (95% CI: 16.6-21.2) versus 17.7 g (95% CI: 13.2-22.2), P=0.63]. No significant difference in weight gain between the two groups was seen (P=0.6). However, there was a trend towards weight gain in the dining room group. CONCLUSION: Food intake can be improved by using a supervised dining room, and this will potentially lead to weight gain and corresponding improvements in nutritional status and rehabilitation. 相似文献
157.
Intracranial EEG versus flumazenil and glucose PET in children with extratemporal lobe epilepsy 总被引:6,自引:0,他引:6
Muzik O da Silva EA Juhasz C Chugani DC Shah J Nagy F Canady A von Stockhausen HM Herholz K Gates J Frost M Ritter F Watson C Chugani HT 《Neurology》2000,54(1):171-179
OBJECTIVE: To compare abnormalities determined in 2-deoxy-2-[18F]fluoro-D-glucose (FDG) and [11C]flumazenil (FMZ) PET images with intracranial EEG data in patients with extratemporal lobe epilepsy. BACKGROUND: Although PET studies with FDG and FMZ are being used clinically to localize epileptogenic regions in patients with refractory epilepsy, the electrophysiologic significance of the identified PET abnormalities remains poorly understood. METHODS: We studied 10 patients, mostly children (4 boys, 6 girls, aged 2 to 19 years; mean age, 11 years), who underwent FDG and FMZ PET scans, intracranial EEG monitoring, and cortical resection for intractable epilepsy. EEG electrode positions relative to the brain surface were determined from MRI image volumes. Cortical areas of abnormal glucose metabolism or FMZ binding were determined objectively based on asymmetry measures derived from homotopic cortical areas at three asymmetry thresholds. PET data were then coregistered with the MRI and overlaid on the MRI surface. A receiver operating characteristics (ROC) analysis was performed to determine the specificity and sensitivity of PET-defined abnormalities against the gold standard of intracranial EEG data. RESULTS: FMZ PET detected at least part of the seizure onset zone in all subjects, whereas FDG PET failed to detect the seizure onset region in two of 10 patients. The area under the ROC curves was higher for FMZ than FDG PET for both seizure onset (p = 0.01) and frequent interictal spiking (p = 0.04). Both FMZ and FDG PET showed poor performance for detection of rapid seizure spread (area under the ROC curve not significantly different from 0.5). CONCLUSIONS: [11C]flumazenil (FMZ) PET is significantly more sensitive than 2-deoxy-2-[18F]fluoro-D-glucose (FDG) PET for the detection of cortical regions of seizure onset and frequent spiking in patients with extratemporal lobe epilepsy, whereas both FDG and FMZ PET show low sensitivity in the detection of cortical areas of rapid seizure spread. The application of PET, in particular FMZ PET, in guiding subdural electrode placement in refractory extratemporal lobe epilepsy will enhance coverage of the epileptogenic zone. 相似文献
158.
159.
CJT De Amorim e Silva A Mackenzie LM Hallowell SE Stewart MR Ditchfield 《Journal of Medical Imaging and Radiation Oncology》2006,50(4):319-323
The aim of this study was to evaluate the effectiveness of a practice magnetic resonance unit, in preparing children to undergo magnetic resonance procedures without general anaesthesia (GA) or sedation. The records of children who attended the practice MRI between February 2002 and April 2004 were retrospectively reviewed. Each record was assessed as to whether the child had passed or failed the practice MRI intervention. Those children who were considered to have passed and were proceeded to a clinical non‐GA MRI had the report of the clinical scan reviewed. If the scan had been reported as non‐diagnostic because of movement artefact it was classified as a failed scan, otherwise it was considered a pass. One hundred and thirty‐four children undertook a practice MRI (age range 4.1–16.1 years, median age 7.7 years, 47% boys) and 120/134 (90%) passed the practice session. In all, 117/120 (98%) subsequently had a clinical non‐GA MRI and 110/117 (94%) passed (median age 7.8 years, 47% boys). Preparation is a safe and effective method to reduce the need for sedation and GA in children undergoing a clinical MRI scan. It provides a positive medical experience for children, parents and staff, and results in cost savings for the hospital. 相似文献
160.
Frost HM 《Journal of bone and mineral metabolism》2000,18(5):278-282
Threshold strain ranges help to control the ability of modeling to increase bone strength and "mass" and the ability of
remodeling to conserve or decrease them. Whether expressed as strains or stresses, the probable remodeling threshold of bone
(MESr) lies below its modeling threshold (MESm), which lies below its operational microdamage threshold (MESp), which lies
well below its ultimate strength (Fx). Given normal modeling and remodeling potentials, that arrangement should tend to cause
whole-bone strength and stiffness to keep typical peak bone strains ("E") from voluntary activities from exceeding bone's
modeling threshold and therefore from reaching its microdamage threshold. Satisfying that laddered "MESr < "E" < MESm << MESp
<<< Fx" arrangement should minimize fatigue failures of bones, which might be at least one purpose of normal bone design.
That arrangement would have practical implications that include, in part, the following. (A) It could make healthy young adult
bones about six times stronger than needed for the largest voluntary loads they usually carry. (B) It suggests a biomechanical
pathogenesis for different kinds of osteoporosis. (C) It suggests design criteria that load-bearing bone implants and endoprostheses
should satisfy to endure their voluntary mechanical usage. (D) It also suggests features that future models of mechanical
loading effects on bone strength, architecture, and "mass" might incorporate.
Received: October 20, 1999 / Accepted: February 10, 2000 相似文献