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81.
BACKGROUND: Telemedicine, based on the use of interactive video consultations, is being used more commonly in rural settings. This development is potentially important to rural patients because there are fewer physicians, particularly specialist physicians, in rural areas. Declining costs of telemedicine equipment and transmission have created increased access to these technologies for rural family physicians and their patients. METHODS: This study considers satisfaction levels of rural family physicians, academic-based specialists, and rural patients in 130 consultations between rural physicians, rural patients, and urban academic specialists. To increase the practicability for rural use, low-cost equipment and low-bandwidth digital telephone transmission lines were utilized. Data were collected using questionnaires that were completed by patients, family physicians, and specialist consultants after each consultation. RESULTS: All categories of participants noted very high levels of satisfaction. CONCLUSION: Telemedicine-based consultations are well accepted by rural patients, rural family physicians, and urban academic specialist consultants. This approach could offer a useful adjunct to rural health care.  相似文献   
82.
A light microscopic and immunohistochemical evaluation of scars   总被引:3,自引:0,他引:3  
BACKGROUND: Scars are commonly encountered by dermatopathologists and usually do not present a diagnostic challenge. However, in some cases, the pathologist may need to consider a broad differential diagnosis including fibrohistiocytic tumors, smooth muscle tumors, myofibroblastic proliferations and desmoplastic malignant melanoma. Although specific histologic aspects of scars have been well studied, a complete histochemical profile of scars, especially at various stages of evolution, has not been described. METHODS: Twenty-five cases of scars including 8 normal scars, 5 hypertrophic scars and 12 keloids were studied. Sections were examined with Verhoeff van Giesson, colloidal iron, Giemsa, smooth muscle actin (SMA), CD34, Factor XIIIa and S-100. RESULTS: All scars were negative for CD34 expression. Factor XIIIa immunostaining identified only rare dermal dendrocytes. S-100 was absent in 23 of 25 cases and stained scattered cells (less than 10%) in the other 2 cases. SMA was positive in 14 of 25 cases with 6 of these showing staining of up to 50% of spindled cells. Elastic fibers were markedly reduced or absent in all cases, mucin showed moderate or marked staining in three-fourths of the cases and dermal mast cells showed a moderate increase in 5 cases. CONCLUSIONS: These findings confirm prior reports that negative staining with CD34, Factor XIIIa and S-100 can help differentiate scars from dermatofibrosarcoma protuberans, dermatofibroma and desmoplastic malignant melanoma, respectively. SMA staining is much more variable and requires careful interpretation.  相似文献   
83.
Background: Access to diagnostic endoscopy is limited in rural and remote Western Australia. Published reports suggest open access referrals may result in over‐servicing, this is reduced by adherence to the American Society for Gastrointestinal Endoscopy (ASGE) guidelines.The aim was to assess whether an out reach surgical service offering open access endoscopy to rural areas was being over utilized. Methods: Prospective data collection from all patients undergoing upper and lower endoscopy procedures between January 1996 and June 2000 were included in the present study. Indications for referral between the general practitioners and the visiting surgeons were reviewed in patient records and assessed for compliance with the ASGE guidelines. The groups were analysed for appropriateness of referrals and frequency of positive pathology investigations. Records for all patients undergoing colonoscopy were reviewed to determine the reason and number of cancelled procedures. Results: A total of 772 endoscopies were performed and 75% were booked as open access services. The referral rate for procedures was greater for general practitioners (583) compared to the visiting surgeons (189), the overall compliance rate for approved indications using the ASGE guidelines for both groups was 92%. There was no significant difference in pathology found between groups. Conclusion: The present study shows that an outreach rural surgical service programme in Western Australia offering open access endoscopy conforms to international guidelines and does not induce unnecessary procedures. Rural patients benefit from a personal cost savings andconvenience. There is an associated reduction in government‐assisted travel costs to larger centres as well as decreased waiting lists.  相似文献   
84.
85.
PURPOSE: Squamous esophageal cancer is common in non-Western countries and has a well-defined progression of preinvasive dysplasia leading to invasive squamous cell carcinoma. We examined the changes in promoter region methylation occurring during neoplastic progression. EXPERIMENTAL DESIGN: The frequency of epigenetic changes in the promoter region of 14 genes epigenetically silenced in other cancers was determined and examined the most frequent changes in dysplastic lesions using methylation-specific PCR. Invasive squamous carcinomas, low to high grade dysplasia, and normal esophagus were then examined for methylation changes in the promoter region of each of the eight most commonly methylated genes. RESULTS: Methylation was most frequent for CDKN2A/p16INK4a (52%) but was also common for O(6)-methylguanine-DNA methyltransferase, E-cadherin (CDH1), and retinoic acid receptor beta2. Methylation at individual genes increased in frequency from normal to invasive cancer. Methylation of MLH1 was associated with microsatellite instability in most cases. The number of genes methylated in individual lesions increased as cellular atypia increased. In individual patients, cancers adjacent to dysplasia had the same epigenetic alterations as the less advanced lesions but often had additional methylation of other genes. CONCLUSIONS: These findings suggest that epigenetic progression parallels the histologic changes observed in the progression of squamous carcinoma of the esophagus.  相似文献   
86.
The intergenic region (IGR) separating the genes for vasopressin (VP) and oxytocin (OT) has been shown to be critical for the cell-specific expression of these peptide genes in hypothalamic neurons. To date, the most relevant information about the putative cis-elements in the IGR that might determine cell-specific gene expression has come from studies in transgenic models. As a first step toward increasing the efficiency of the IGR sequence deletion studies in transgenic animals, a comparative genomics approach comparing the IGR sequence in humans versus mice was used to identify conserved sequences that might be candidate regulatory elements. The nucleotide sequence of the IGR between the human VP and OT genes was determined and compared to the mouse IGR, and 26 conserved sequences in three distinct clusters were found. These conserved sequences and motifs may be important for the cell-specific expression of the VP and OT genes. However, before further significant progress can be made, a "high-throughput" method for the analysis of deletion constructs in relevant cell types in vitro is needed. It is proposed here that organotypic culture models combined with the use of particle-mediated gene transfer methods may provide an effective, general strategy for the study of cell-specific expression in the central nervous system.  相似文献   
87.
88.
Background : Recent studies suggest that coeliac disease (CD) is one of the commonest, life-long disorders in Italy. The aims of this multicentre work were: (a) to establish the prevalence of CD on a nationwide basis; and (b) to characterize the CD clinical spectrum in Italy. Patients and methods : Fifteen centres screened 17201 students aged 6–15 years (68.6% of the eligible population) by the combined determination of serum IgG- and IgA-antigliadin antibody (AGA) test; 1289 (7.5%) were IgG and/or IgA-AGA positive and were recalled for the second-level investigation; 111 of them met the criteria for the intestinal biopsy: IgA-AGA positivity and/or AEA positivity or IgG-AGA positivity plus serum IgA deficiency. Results : Intestinal biopsy was performed on 98 of the 111 subjects. CD was diagnosed in 82 subjects (75 biopsy proven, 7 not biopsied but with associated AGA and AEA positivity). Most of the screening-detected coeliac patients showed low-grade intensity illness often associated with decreased psychophysical well-being. There were two AEA negative cases with associated CD and IgA deficiency. The prevalence of undiagnosed CD was 4.77 × 1000 (95% CI 3.79–5.91), 1 in 210 subjects. The overall prevalence of CD, including known CD cases, was 5.44 × 1000 (95% CI 4.57–6.44), 1 in 184 subjects. The ratio of known to undiagnosed CD cases was 1 in 7. Conclusions : These findings confirm that, in Italy, CD is one of the most common chronic disorders showing a wide and heterogeneous clinical spectrum. Most CD cases remain undiagnosed unless actively searched.  相似文献   
89.
PURPOSE: Incidence data for severe aplastic anaemia (SAA) in children are scanty and vary. Few population based studies have been reported. A retrospective and prospective study was conducted to determine the incidence and course of SAA. PATIENTS AND METHODS: All children with a diagnosis of SAA in the Nordic countries from 1982 through 1993 were registered and have been followed up since 1987. RESULTS: A total of 101 children were diagnosed with SAA. The mean annual child population was 4.31 million. A constant incidence of 1.95/million children/year was found: 2.4 for boys and 1.5 for girls. A non-significant increase of cases occurred from November to March. Possible aetiological agents were noted in 29%. The actuarial survival was 79% after one year and 68% after five years without significant difference between boys and girls. CONCLUSION: The incidence of SAA in the Nordic countries remains stable with a preponderance among boys. SAA has still a high initial mortality and a risk of late deaths.  相似文献   
90.
Objective To assess the extent to which women contribute to1 the decision for caesarean section and their satisfaction with the decision and procedure.
Design Observational study of women undergoing caesarean section who were interviewed using a standard proforma.
Setting University College Hospital, London.
Participants One hundred and two consecutive women Undergoing caesarean section.
Results The women's perceived reason for the caesarean section agreed with the doctors' reason in 91 cases (89.2%). Only 2/29 women having elective sections stated they had no contribution, compared with 22/73 women having emergency sections (   P = 0.018, two-tailed Fisher's exact test  ). Twenty out of 29 women (69%) having elective procedures and 37/73 women (51%) having emergency sections recorded medium or more contribution. All women except one were 50% or more satisfied with the decision. Women's satisfaction with the operation was high in the immediate post-operative period and remained so over the following six weeks. Forty-three women (49%) said they would prefer an elective section in the next pregnancy given the choice.
Conclusions Women undergoing caesarean section were well informed and took a considerable part in the decision-making process. This suggests that women's wishes may be playing a role in increasing caesarean section rates. High levels of satisfaction with both the decision and the procedure itself indicate that caesarean section is an acceptable method of delivery, particularly when an elective procedure.  相似文献   
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