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Over recent decades, the use of in vitro diffusion cell studies to assess skin permeability has evolved into a major research tool, providing key insights into the relationships between skin, drug and formulation. Sometimes, such studies involve synthetic membranes as this approach can yield useful inferences with respect to drug-skin partitioning and diffusion phenomena. Yet despite the popularity of such studies, it is still not at all known whether typical solute transport across synthetic barriers results in a normal distribution of permeability coefficients or alternatively some type of skewed distribution. The present study aims to shed light on this issue. To this end, five compounds (testosterone, oestradiol, corticosterone, aldosterone and adenosine) exhibiting a broad range of octanol-water partition coefficient values were selected as test penetrants. The protocol involved taking multiple replicate measurements of each drug's passive steady state flux through poly(dimethylsiloxane) membrane. Each penetrant's resultant permeability coefficient database was subjected to a Kolmogorov-Smirnov (KS) test for normality. It was found that the permeability coefficients of all five drugs were distributed in a Gaussian-normal fashion. The theoretical significance and practical impact of these findings are discussed.  相似文献   
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? The paper describes a multiproject practice development programme undertaken over a period of 1 year. ? The background and development of the programme are outlined, whilst attention is paid to the innovatory nature of the work, particularly the use of inductive, deductive and integrated approaches to both change implementation and project supervision. ? The programme was monitored throughout using different data sources and the paper uses evaluative material retrospectively to provide answers to organizational and professional difficulties which arose during the course of the programme. ? The authors conclude that the use of combinations of different models for practice development has potential, but requires careful supervision. ? They also recommend that those involved in practice development are made fully aware of its local or micropolitics, and develop strategies to deal with change before it occurs, not after it has taken place.  相似文献   
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BACKGROUND: To investigate incidence and number of abnormal cerebral hyperintensities (ACFs) in Magnet Resonance Imaging (MRI) and its relation to a patent foramen ovale (PFO) in divers with no history of decompression illness. METHODS: Cohort study on 50 divers (21-5500 dives). MAIN OUTCOME MEASURES: Incidence and number of ACFs visualized by cranial MRI and presence and size of a PFO as documented by echocardiography and transcranial Doppler ultrasound (TCD) with echocontrast. RESULTS: A total of 137 ACFs was found in the 50 subjects, with a significant correlation between the number of dives and number of ACFs (r = 0.28; p < 0.05); but after correction for age, the remaining correlation (r = 0.15) did not reach significance. In 18 divers, a PFO was present by either the application of echocardiography or TCD; in 12 divers, the PFO was of high hemodynamic relevance. Ten of 18 divers with a PFO had at least one ACF, while in the remaining 32 divers, only 14 had at least one ACF (56% versus 44%, p = NS). Seven of 14 divers (50%) with 4 ACFs had a PFO, compared to 11 of 36 (31%) with less than 4 ACFs (p = NS). CONCLUSION: In this cohort of healthy divers, in contrast to an earlier report, no significant association was found between PFO presence and incidence or number of ACFs.  相似文献   
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Attention-deficit/hyperactivity disorder (ADHD) is associated with impairments in occupational, social, and educational functioning in adults. This study examined relations of adaptive impairment to ADHD symptom domains (inattentive-disorganized and hyperactive-impulsive) and to deficits in executive functioning (EF) in 195 well-characterized adults (105 ADHD, 90 non-ADHD, between ages 18 and 37). Participants completed a battery of EF measures as well as assessments of adaptive functioning. Confirmatory factor analyses were used to validate latent factors for adaptive functioning and EF. In a measurement model, weaker EF was associated with poorer adaptive functioning (r = -.30). When multi-informant composite variables for current inattentive-disorganized and hyperactive-impulsive ADHD symptoms were included in the structural model, EF no longer predicted adaptive functioning. While both symptom composites were similarly related to EF (inattentive-disorganized r = .36; hyperactive-impulsive r = .29), inattentive-disorganized symptoms accounted for more variance in adaptive functioning (67.2% vs. 3.6%). Furthermore, for retrospectively reported childhood symptoms of ADHD, only the inattentive-disorganized symptom domain was related to EF or adaptive impairment. These results suggest that, in adults with ADHD, inattentive-disorganized symptoms may be the primary contributor to key aspects of poorer adaptive function and may be the behavioral path through which EF deficits lead to adaptive impairment.  相似文献   
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Efforts to control chlamydial and gonococcal infections include notifying eligible sexual partners of possible infection, primarily by asking the diagnosed patient to notify their partners. This approach, known as patient referral, is widely used but poorly understood. The current study examined psychosocial and cognitive factors associated with patient referral among an urban, minority sample of 168 participants recently diagnosed with Chlamydia trachomatis or Neisseria gonorrhoeae. At a follow-up interview 1-month from diagnosis, participants were more likely to have notified all eligible partners if they had greater intention to notify at baseline (OR = 3.72; 95% CI = 1.34, 10.30) and if they had only one partner at baseline (OR = 4.08; 95% CI = 1.61, 10.31). There were also gender differences as well as differences based on type of partner (i.e., regular, casual, one-time). The implications of these findings for the design of programs to promote patient referral for sexually transmitted infections are discussed. Schwartz, Malka, Augenbraun, McCormack, and Wilson are with the State University of New York, Downstate Medical Center, Brooklyn, NY, USA; Rubin is with the New York City Department of Health, Bureau of STD Control, New York, NY, USA; Rubin, Hogben, and Liddon are with the Centers for Disease Control and Prevention, Atlanta, GA, USA; Schwartz is with the Department of Preventive Medicine and Community Health, SUNY Downstate Medical Center, Box 1240, 450 Clarkson Avenue, Brooklyn, NY 11203, USA.  相似文献   
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