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Pendred syndrome is an autosomal recessive disease characterised by congenital sensorineural deafness and goitre. The gene responsible for Pendred syndrome has been mapped to chromosome 7q31 in a 5.5 centimorgan (cM) interval flanked by D7S501 and D7S523. This interval was recently refined a to 1.7 cM interval located between D7S501 and D7S692. In the present study, we report linkage analysis data on a large consanguineous family genotyped with eight microsatellite markers located between D7S501 and D7S523. Complete cosegregation with the disease locus was observed with the loci analysed, which further supports locus homogeneity for Pendred syndrome and close linkage to this region. Haplotype analysis placed the Pendred syndrome gene between D7S496 and D7S2425 in a 0.8 cM interval. This additional refinement of the Pendred syndrome region will facilitate the construction of a physical map of the region and will help the identification of candidate genes.  相似文献   
13.
Tumor cell marker antibodies were used to analyze ten cases of hepatocellular carcinoma associated with cirrhosis. Clinically, eight of these cases gave a history of chronic alcoholism and the other two of hepatitis B virus infection. Formalin-fixed, paraffin-embedded sections from these cases were screened with antibodies against alpha fetoprotein (AFP), hepatitis B surface antigen (HBsAg) and carcinoembryonic antigen (CEA) using the peroxidase antiperoxidase and avidin-biotin immunoperoxidase procedures. Three cases were positive for AFP, four for HBsAg, and three for CEA; two cases had both HBsAg and CEA. Alpha fetoprotein was present only in the cytoplasm of tumor cells in three cases. Hepatitis B surface antigen, on the other hand, was present in the cytoplasm of hepatocytes in cirrhotic areas and, in one out of the four cases, was also present in hepatocellular carcinoma cells. Carcinoembryonic antigen was seen in three cases; it was present on the surface and in the cytoplasm of proliferating ducts within the cirrhotic areas and between cell surfaces of individual tumor cells in two cases. The presence of different markers was not related to the microscopic appearance of the tumors. In one case, positivity for AFP was of diagnostic help in a tissue sample obtained by needle biopsy. The avidin-biotin immunoperoxidase procedure was more sensitive than the peroxidase antiperoxidase (PAP technique in the pathological assessment of autopsy specimens. Our findings are in agreement with those of other reports and indicate that AFP and HBsAg are the most commonly found markers in hepatoma associated with cirrhosis, and that CEA staining is variable and hepatoma associated with cirrhosis, and that CEA staining is variable and probably non-contributory.  相似文献   
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A cross-sectional exploratory study was conducted to assess nurses and midwives’ attitudes and beliefs towards addressing patients' sexual health. A convenient sample of 305 nurses and midwives (professionals and students) were recruited from University Hospitals in Lebanon. The Sexuality Attitude and Belief Survey (SABS) was used and data about barriers to sexual assessment, sexual education and sociodemographic characteristics were collected. The sample included nursing students, 30.1%, staff nurses, 61.2%, and midwives, 8.6%. The mean age was 26.8 years, and 83.7% were females. Only 28.4% of the total sample received sexual health education, and 12.5% reported taking patients' sexual history. The total SABS score was 48.4, which is relatively high. Most nurses and midwives (72.2%) stated that they do not spend time discussing patients' sexual concerns, viewing sexuality as 'too private an issue to discuss' (68.9%). In parallel, a minority had the belief that patients expect nurses to ask about their sexual concerns (32.7%) and felt confident in their abilities to address patients' sexual issues (30.3%). SABS score was significantly associated with the participants' gender, status, care unit, sexual health education and history taking. This study provided a preliminary appraisal of Lebanese nurses' and midwives' approaches towards patients' sexual health assessment and highlighted the obstacles that hinder appropriate sexual health practice. Based on the findings, there is a need for initiatives at the level of education and practice to develop nurses and midwives' competence and improve patient outcomes.

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16.
Needle biopsy of renal allografts: comparison of two techniques   总被引:2,自引:0,他引:2  
Two techniques for renal allograft biopsy were retrospectively evaluated to compare relative safety and efficacy. After ultrasound (US) localization of the kidney and biopsy with a hand-held 14-gauge cutting needle, an adequate specimen was obtained in 74 of 77 cases (96%). Major complications occurred in six of these 77 cases (8%). One hundred four biopsies were performed by using a smaller 18-gauge cutting needle with a spring-loaded biopsy "gun" and real-time US guidance. With this newer technique, specimens adequate for diagnosis were obtained in 99 biopsies (95%). There was a single major complication with this technique (1%). The 18-gauge needle with real-time US guidance yields comparably adequate specimens with a lower frequency of complications.  相似文献   
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Enterotoxin-producing Escherichia coli are major causes of pediatric diarrhea in developing countries. The heat-stable enterotoxin of Escherichia coli (STa) causes diarrhea by virtue of its ability to bind to and stimulate intestinal membrane-bound guanylate cyclase, generating cyclic GMP (cGMP). Previous work showed that a fucosylated oligosaccharide fraction of human milk was able to protect suckling mice from the secretory effects of STa, but the mechanism of the protection could not be determined. Oligosaccharide fractions from human milk were tested for their ability to block the biochemical effects of STa in T84 cells, a human colon carcinoma line responsive to the toxin. Total and fucosylated oligosaccharide fractions were found to inhibit STa-stimulated guanylate cyclase activity in T84 cell membranes and cGMP production in intact T84 cells by 60-80%. In addition, the total oligosaccharide fraction and the fucosylated oligosaccharide fraction inhibited 125I-STa binding significantly (17% and 27% inhibition, respectively). These findings demonstrate the protective activity of human milk oligosaccharides against STa in a human-derived cell line and show that the biochemical step blocked by oligosaccharides is STa-mediated stimulation of guanylate cyclase. This represents a novel mechanism by which human milk oligosaccharides protect against diarrhea.  相似文献   
19.
Multinucleated giant cells (MNGCs) are reported in many thyroid lesions. This study examines whether their quantity and quality can help in the differential diagnosis. All fine-needle aspirations (FNAs) of the thyroid with a "significant" number of MNGCs were reviewed from 1995 -1998. There were 23 cases (<1% of thyroid FNAs): 8 papillary carcinomas (PC), 4 subacute thyroiditis (ST), 3 granulomas, 7 adenomatous goiters (AG), and one Hurthle-cell adenoma (HA). MNGCs with dense cytoplasm were seen exclusively in PC, ST, and granulomas. They had angulated shapes. They were most numerous, largest, and with the highest number of nuclei in ST and granulomas. MNGCs with foamy cytoplasm were seen in AG and HA and 80% of the other cases (PC, ST, and granulomas). In PC, rare MNGCs had intranuclear inclusions and grooves. The accompanying cell population was characteristic of each disease. The quantity and quality of MNGCs in thyroid FNA may be helpful in narrowing the differential diagnosis. Diagn. Cytopathol. 1999;21:307-312.  相似文献   
20.
Laser in situ keratomileusis for the treatment of myopia   总被引:3,自引:0,他引:3  
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