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Brian T. Maurer Steven I. Moreno Amy R. Pickard Brooke E. Wurst Daniel K. Norden H. Ralph Schumacher 《Arthritis \u0026amp; Rheumatology》1995,8(3):161-166
Objective . Patient recruitment often involves a great deal of effort and cost. We sought to determine successful recruitment methods for an osteoarthritis (OA) exercise study, and to subsequently focus on using those approaches. Methods. Eleven methods were developed to recruit subjects for this large research project. Financial constraints ensured that we focused on low-cost measures. Over a 20-month period, the numbers of both total respondents and eventual participants were recorded. Results. Responses were recorded for 263 individuals, and 108 subjects entered the study. The most successful recruitment method was via physician referrals from affiliated clinics. In general, methods that were free of direct cost seemed no less successful than those requiring expenditures. Conclusion. Successful subject recruitment, even for a large study, may not require costly advertising. Direct contact and frequent reminders rendered to our own clinics proved most effective, but other free and low-cost approaches were also of benefit. 相似文献
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Hanna Pickard 《The Hastings Center report》2020,50(4):37-46
The landscape of addiction is dominated by two rival models: a moral model and a model that characterizes addiction as a neurobiological disease of compulsion. Against both, I offer a scientifically and clinically informed alternative. Addiction is a highly heterogenous condition that is ill-characterized as involving compulsive use. On the whole, drug consumption in addiction remains goal directed: people take drugs because drugs have tremendous value. This view has potential implications for the claim that addiction is, in all cases, a brain disease. But more importantly, it has implications for clinical and policy interventions. To help someone overcome addiction, you need to understand and address why they persist in using drugs despite negative consequences. If they are not compelled, then the explanation must advert to the value of drugs for them as an individual. What blocks us from acknowledging this reality is not science but fear: that it will ignite moralism about drugs and condemnation of drug users. The solution is not to cleave to the concept of compulsion but to fight moralism directly. 相似文献
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B-cell growth factor receptor expression and B-cell growth factor response of leukemic B cell precursors and B lineage lymphoid progenitor cells 总被引:8,自引:1,他引:8
Uckun FM; Fauci AS; Heerema NA; Song CW; Mehta SR; Gajl-Peczalska K; Chandan M; Ambrus JL 《Blood》1987,70(4):1020-1034
The purpose of this study was to analyze the expression of B cell growth factor (BCGF) receptors and to elucidate the biologic effects of biochemically purified natural BCGF at the B cell precursor stage of human B lineage lymphoid differentiation. The specific binding of radioiodinated high-mol-wt BCGF (125I-HMW-BCGF) and low-molecular-wt BCGF (125I-LMW-BCGF) to fresh marrow blasts from B cell precursor acute lymphoblastic leukemia (ALL) patients was initially investigated. The estimated number of radioiodinated BCGF molecules bound per blast ranged from undetectable to 24.3 X 10(3) for HMW-BCGF, and from 11.5 X 10(3) to 457.8 X 10(3) for LMW-BCGF. In 3H-TdR incorporation assays, 75% of cases showed a significant response to LMW-BCGF with a median stimulation index of 9.3. By comparison, only 33% of cases showed a significant response to HMW-BCGF with a median stimulation index of 2.4. Subsequently, B cell precursor colony assays were performed to assess and compare the biologic effects of BCGF on leukemic B lineage lymphoid progenitor cells. Among 28 cases studied, 57% responded to both HMW-BCGF and LMW-BCGF, 21% responded only to LMW-BCGF, and the remaining cases showed no proliferative response to either growth factor. The response patterns of virtually pure populations of FACS- sorted leukemic B cell precursors were essentially identical to the proliferative responses of unsorted leukemic B-cell precursors. Synergistic effects between HMW-BCGF and LMW-BCGF were observed in 80% of the cases that responded to both. The numbers of cell-bound radioiodinated BCGF molecules, the stimulation indices, as well as the number of B cell precursor colonies in BCGF-stimulated cultures showed a marked interpatient variation. Patients with structural chromosomal abnormalities (SCAs) involving 12p11-13 or patients with a Philadelphia chromosome showed a greater HMW-BCGF response at the level of leukemic progenitor cells than did other patients (P = .02). The LMW-BCGF response was significantly greater for patients with SCA than for patients without SCA (P = .04). The response of leukemic progenitor cells to HMW-BCGF or LMW-BCGF did not correlate with sex, age, disease status, FAB morphology, WBC at diagnosis, or immunophenotype. To our knowledge, this study represents the first detailed analyses of BCGF receptor expression and BCGF effects in B cell precursor ALL. The data presented provide direct evidence for the expression of functional receptors for both HMW-BCGF and LMW-BCGF in B cell precursor ALL. 相似文献
67.
Management of high grade renal trauma: 20-year experience at a pediatric level I trauma center 总被引:2,自引:0,他引:2
Henderson CG Sedberry-Ross S Pickard R Bulas DI Duffy BJ Tsung D Eichelberger MR Belman AB Rushton HG 《The Journal of urology》2007,178(1):246-50; discussion 250
PURPOSE: In the last 20 years the management of high grade, blunt renal trauma at our institution has evolved from primarily an operative approach to an expectant nonoperative approach. To evaluate our experience with the expectant nonoperative management of high grade, blunt renal trauma in children, we reviewed our 20-year experience regarding evaluation, management and outcomes in patients treated at our institution. MATERIALS AND METHODS: We retrospectively studied all patients sustaining renal trauma between 1983 and 2003. Medical records were reviewed for mechanism of injury, assigned grade of renal injury, patient treatment, indications for and timing of surgery, and outcome. Injuries were categorized as either low grade (I to III) or high grade (IV to V). RESULTS: We reviewed the medical records of 164 consecutive children who sustained blunt renal trauma between 1983 and 2003. A total of 38 patients were excluded for inadequate information. Of the remaining 126 children 60% had low grade and 40% had high grade renal injuries. A total of 11 patients (8.7%) required surgical or endoscopic intervention for renal causes, including 2 for congenital renal abnormalities and 1 for clot retention. Eight patients (6.3%) required surgical intervention for isolated renal trauma, of whom 2 (1.6%) required immediate surgical intervention for hemodynamic instability and 6 (4.8%) were treated with a delayed retroperitoneal approach. Only 4 patients (3.2%) required nephrectomy. All patients receiving operative intervention had high grade renal injury. CONCLUSIONS: Initial nonsurgical management of high grade blunt renal trauma in children is effective and is recommended for the hemodynamically stable child. When a child has persistent symptomatic urinary extravasation delayed retroperitoneal drainage may become necessary to reduce morbidity. Minimally invasive techniques should be considered before open operative intervention. Early operative management is rarely indicated for an isolated renal injury, except in the child who is hemodynamically unstable. 相似文献
68.
A long‐acting pegylated recombinant human growth hormone (Jintrolong®) in healthy adult subjects: Two single‐dose trials evaluating safety,tolerability and pharmacokinetics 下载免费PDF全文
69.
Evaluation of a new enzyme-linked immunosorbent assay test for rotavirus antigen in faeces 总被引:6,自引:0,他引:6 下载免费PDF全文
A new commercial test for the diagnosis of rotavirus gastroenteritis was assessed. With some modifications it compared favourably with electron microscopy and immunofluorescence. 相似文献
70.
Despina A. Lalou Marek Czosnyka Joseph Donnelly Andrea Lavinio John D. Pickard Matthew Garnett 《Neurological research》2013,35(7):587-592
Objective: Slow vasogenic intracranial pressure (ICP) waves are spontaneous ICP oscillations with a low frequency bandwidth of 0.3–4 cycles/min (B-waves). B-waves reflect dynamic oscillations in cerebral blood volume associated with autoregulatory cerebral vasodilation and vasoconstriction. This study quantifies the effects of general anaesthesia (GA) on the magnitude of B-waves compared to natural sleep and conscious state.Materials and methods: The magnitude of B-waves was assessed in 4 groups of 30 patients each with clinical indications for ICP monitoring. Normal pressure hydrocephalus patients undergoing Cerebrospinal Fluid (CSF) infusion studies in the conscious state (GROUP A) and under GA (GROUP B), and hydrocephalus patients undergoing overnight ICP monitoring during physiological sleep (GROUP C) were compared to deeply sedated traumatic brain injury (TBI) patients with well-controlled ICP during the first night of Intensive Care Unit (ICU) stay (GROUP D).Results: A total of 120 patients were included. During CSF infusion studies, the magnitude of slow waves was higher in conscious patients (GROUP A: 0.23+/?0.10 mm Hg) when compared to anaesthetised patients (GROUP B: 0.15+/?0.10 mm Hg; p = 0.011). Overnight magnitude of slow waves was higher in patients during natural sleep (GROUP C: 0.20+/?0.13 mm Hg) when compared to TBI patients under deep sedation (GROUP D: 0.11+/? 0.09 mm Hg; p = 0.002).Conclusion: GA and deep sedation are associated with a reduced magnitude of B-waves. ICP monitoring carried out under GA is affected by iatrogenic suppression of slow vasogenic waves of ICP. Accounting for the effects of anaesthesia on vasogenic waves may prevent the misidentification of potential shunt-responders as non-responders. 相似文献