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11.
Decisions on DSM-IV criteria for alcohol dependence were based in part on latent structure analyses of field survey data on alcohol problems. Analogously, to investigate the latent structure of nicotine dependence in an epidemiological sample, we carried out a dichotomous item factor analysis of DSM-III-R symptom data gathered from 394 young adults who reported a history of sustained daily smoking. Smokers and their dependence symptoms were identified by means of the NIMH Diagnostic Interview Schedule version III revised, administered to a random sample of 1007 21–30-year-olds who were members of a health maintenance organization in the Detroit area. Comparing different latent structure models using LISCOMP software with bootstrap re-sampling, followed by multiple logistic regression, vie found that a two-factor model indicating a ‘general dependence’ and a ‘failed cessation’ dimension best accounted for the observed data. Current smoking status (persistent vs. past smoking) was associated with the two factors independently. Replication and additional research on construct, discriminant and convergent validity are needed.  相似文献   
12.
ANDERSON, M.H., ET AL.: Ventricular Pacing from the Atrial Channel of a DDD Pacemaker: A Consequence of Pacemaker Twiddling? The breakdown of pacemaker lead insulation under conditions of mechanical stress leading to failure of pacing is well recognized. We present a case where adjacent breakdown of insulation in two unipolar pacing leads resulted in inappropriate ventricular pacing. Replacement of the leads rectified the problem. [PACE, Vol. 13, December, Part I 1990)  相似文献   
13.
PURPOSE: Congenital anterior urethrocutaneous fistula is a rare anomaly that may present in an isolated fashion or in association with other penile abnormalities, such as chordee or hypospadias. There have been 18 cases of congenital anterior urethrocutaneous fistula reported in the literature. We present 14 additional cases of congenital anterior urethrocutaneous fistula. MATERIALS AND METHODS: We treated 14 patients with congenital anterior urethrocutaneous fistula, of whom 9 were uncircumcised at presentation. Two patients had evidence of chordee and 4 had distal hypospadias. RESULTS: The type of repair was determined by the anatomical variations of this anomaly. All cases were corrected electively by various techniques based on the degree of the defect, including primary closure via a Thiersch-Duplay urethroplasty, pedicle flap urethroplasty, hinged flap urethroplasty and interpositioned island pedicle tube or onlay urethroplasty. CONCLUSIONS: To our knowledge the embryological events that cause anterior urethrocutaneous fistula are unclear but they likely result from a defective urethral plate or an abnormality of the infolding of the urethral groove. Surgical technique must be individualized to fit the defect. While there has been considerable skepticism regarding the existence of congenital urethrocutaneous fistula, the fact that 9 of our 14 patients were uncircumcised confirms the congenital nature of this lesion.  相似文献   
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The chondrocyte and its pericellular microenvironment together represent the chondron, historically considered the primary structural, functional and metabolic unit of articular and other hyaline cartilages. This review summarises research over the last 10 years to establish the molecular anatomy, functional properties and metabolic contribution of the chondron in articular cartilage homeostasis, and its failure during the initiation and progression of degenerative osteoarthritis.  相似文献   
16.
A lymphocytic enterocolitis has been reported in a cohort of children with autistic spectrum disorder (ASD) and gastrointestinal (GI) symptoms. This study tested the hypothesis that dysregulated intestinal mucosal immunity with enhanced pro-inflammatory cytokine production is present in these ASD children. Comparison was made with developmentally normal children with, and without, mucosal inflammation. Duodenal and colonic biopsies were obtained from 21 ASD children, and 65 developmentally normal paediatric controls, of which 38 had signs of histological inflammation. Detection of CD3+ lymphocyte staining for spontaneous intracellular TNF, IL-2, IL-4, IFN, and IL-10, was performed by multicolor flow cytometry. Duodenal and colonic mucosal CD3+ lymphocyte counts were elevated in ASD children compared with noninflamed controls (p<0.03). In the duodenum, the proportion of lamina propria (LP) and epithelial CD3+TNF+ cells in ASD children was significantly greater compared with noninflamed controls (p<0.002) but not coeliac disease controls. In addition, LP and epithelial CD3+IL-2+ and CD3+IFN+, and epithelial CD3+IL-4+ cells were more numerous in ASD children than in noninflamed controls (p<0.04). In contrast, CD3+IL-10+ cells were fewer in ASD children than in noninflamed controls (p<0.05). In the colon, LP CD3+TNF+ and CD3+IFN+ were more frequent in ASD children than in noninflamed controls (p<0.01). In contrast with Crohns disease and non-Crohns colitis, LP and epithelial CD3+IL-10+ cells were fewer in ASD children than in nondisease controls (p<0.01). There was a significantly greater proportion of CD3+TNF+ cells in colonic mucosa in those ASD children who had no dietary exclusion compared with those on a gluten and/or casein free diet (p<0.05). There is a consistent profile of CD3+ lymphocyte cytokines in the small and large intestinal mucosa of these ASD children, involving increased pro-inflammatory and decreased regulatory activities. The data provide further evidence of a diffuse mucosal immunopathology in some ASD children and the potential for benefit of dietary and immunomodulatory therapies.  相似文献   
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18.
Sinus Node Reentrant Tachycardia   总被引:2,自引:0,他引:2  
This review article discusses the electrophysiological basis of sinus node reentry, clinical features of sinus node reentry, and the management of this uncommon tachycardia with drugs and ablative therapy. It also proposes the use of the term "sinoatrial reentrant tachycardia" for this form of tachycardia.  相似文献   
19.
BERNSTEIN, A.D., et al .: The NASPE/BPEG Defibrillator Code. A new generic code, patterned after and compatible with the NASPE/BPEG Generic Pacemaker Code (NBG Code) was adopted by the NASPE Board of Trustees on January 23, 1993. It was developed by the NASPE Mode Code Committee, including members of the North American Society of Pacing and Electrophysiology (NASPE) and the British Pacing and Electrophysiology Group (BPEG). It is abbreviated as the NBD (for NASPE/BPEG Defibrillator) Code. It is intended for describing the capabilities and operation of implanted cardioverter defibrillators (ICDs) in conversation, record keeping, and device labeling, and incorporates four positions designating: (1) shock location; (2) antitachycardia pacing location; (3) means of tachycardia detection; and (4) antibradycardia pacing location. An additional Short Form, intended only for use in conversation, was defined as a concise means of distinguishing devices capable of shock alone, shock plus antibradycardia pacing, and shock plus antitachycardia and antibradycardia pacing. (PACE, Vol. 16, September 1993)  相似文献   
20.
Treatments designed to relieve paradoxical contraction of the anal sphincters during defecation (anismus) have had limited success in children with encopresis. This has raised doubts as to the clinical relevance of this diagnosis in childhood as anorectal dysfunction. Our aim was to determine whether, in patients who had treatment-resistant encopresis, the presence of electromyographic anismus was associated with increased faecal retention. Sixty-eight children with soiling (mean age 8.7 ± 2.06 years) were assessed by clinical examination, abdominal radiography and then with anorectal manometry. Patients with electromyographic anismus (n= 32; 47%) had significantly increased radiographic rectal faecal retention and were significantly less likely to be able to defecate water-filled balloons. There were no significant differences in response to prior therapy, history of primary encopresis, behavioural adjustment or in sociodemographic data. Our results suggest that electromyographic anismus is associated with obstructed defecation and faecal retention.  相似文献   
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