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41.
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Autosomal dominant cerulean cataracts (ADCC) have previously been mapped to two loci: one on chromosome 17q24 and the other on chromosome 22q11.2-q12.2, which includes the beta-B2 crystallin (CRYBB2) candidate gene. Using polymorphic markers in these regions (D17S802, D17S836, D17S1806 and CRYBB2, D22S258) for linkage analysis, we excluded these loci in a large Moroccan family presenting with an unusual form of ADCC with early onset of lens opacities and rapid evolution. This finding confirms the clinical and genetic heterogeneity of autosomal dominant congenital cerulean cataracts.  相似文献   
43.
BACKGROUND: The clinical presentation of tinea is usually, but not always, characteristic. The purpose of this study was to determine whether the routine use of the periodic acid-Schiff (PAS) stain in inflammatory skin disorders is requisite for identifying clinically undiagnosed tinea cases and to ascertain whether there are histopathologic clues that suggest the diagnosis of a dermatophyte infection. METHODS: Hematoxylin and eosin (H&E)-stained slides from 60 PAS-positive tinea cases were examined histologically by two observers. One observer, aware of the diagnosis of tinea, searched for hyphal elements and also recorded in detail epidermal, dermal, and follicular changes. The second observer, not aware of the diagnosis beforehand, reviewed the same slides, together with randomly mixed slides from 21 non-tinea cases, recording the same parameters as the first reviewer. RESULTS: Of the 60 cases of tinea, only 45% were diagnosed clinically. Histologic examination of H&E sections by the two observers disclosed the presence of hyphal elements in 68 and 45%, respectively. No significant histologic differences, except for the presence of hyphae, were observed between tinea and non-tinea cases. CONCLUSIONS: The finding that only 57% of PAS-positive cases of tinea showed hyphal elements on H&E examination alone, together with no other differentiable histologic characteristics, lends strong support for the routine use of PAS-staining for inflammatory skin disorders.  相似文献   
44.
Erosive oral lichen planus (EOLP) is uncommon. We present nine cases of EOLP in patients aged from 39 to 77 years. The aim of our retrospective study was to determine the clinical particularities and the treatment difficulties of this disease.  相似文献   
45.
The purpose of this study is to investigate the association between maternal alcohol intake in pregnancy and the occurrence of early stillbirth using a retrospective cohort analysis of singleton births in Missouri that occurred in the period 1989 through 1997 (N=655,979). We used Cox proportional hazards regression to generate adjusted risk estimates for total, early, and late stillbirth associated with maternal alcohol intake and used the Robust Sandwich Estimator to adjust for intracluster correlations among sibships. Overall, a total of 3,508 counts of stillbirth were identified, yielding a stillbirth rate of 5.3 per 1,000. Among mothers who consumed alcohol during pregnancy, the stillbirth rate was 8.3 per 1,000. Mothers who consumed alcohol while pregnant were 40% more likely to experience stillbirth as compared with nondrinking mothers (adjusted hazards ratio=1.4, 95% confidence interval: 1.2-1.7). A dose-response relationship was evident; mothers who consumed five or more drinks per week during pregnancy experienced a 70% elevated risk of stillbirth compared with nondrinking mothers (adjusted hazards ratio=1.7; 95% confidence interval: 1.0-3.0). The risk of early stillbirth was 80% higher among drinking mothers compared with abstainers (adjusted hazards ratio=1.8; 95% confidence interval: 1.3-2.3). The elevated risks for both early and late stillbirth did not reach statistical significance when broken down by level of alcohol intake. In conclusion, maternal drinking during pregnancy is associated with an increased risk of early stillbirth. These findings underscore the need to reinforce current counseling strategies toward pregnant women and women who intend to conceive on the detrimental effects of alcohol use in pregnancy.  相似文献   
46.
Abstract: Focal dermal hypoplasia is a rare, X-linked dominant syndrome characterized by dysplasla of the skin, skeleton, and central nervous system. We report an intant who was born with severe focal dermal hypoplasla and an epigastric hernia. Operative timing and approach to abdominal wall defects in the presence of severe cutaneous dysplasia are discussed.  相似文献   
47.
Primary teratomas of the fallopian tube are extremely uncommon. To date, only about 50 cases have been reported in the literature. They occur usually in the fourth decade. There association with nulliparity and reduced parity has been noted. Many have been discovered incidentally and none has been diagnosed preoperatively. The majority are cystic, show great variation in size and are commonly located in the ampulla or the isthmus. They can be intraluminal, attached to the serous surface by a pedicule and rarely intramural. Histologically they are similar to teratoma of the ovary and elsewhere. We describe a mature cystic teratoma of the fallopian tube found incidentally in a 35-year-old woman operated for suspicion of ectopic tubal pregnancy. The feature of benign teratoma of the fallopian tube is discussed.  相似文献   
48.
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BACKGROUND: Curriculum-wide implementation of computer-based learning (CBL) in undergraduate medical education remains elusive. Unlike many pilot tests of singular learning programmes, dropout rates are high and acceptance seems low in the long run. We studied the effect of a new CBL programme, suitable for curriculum-wide implementation, on Year 3 medical students' attitudes towards CBL. METHODS: Students from 2 universities participating in a mandatory pharmacology course were given access to a CBL programme covering cardiovascular drug therapy in a controlled randomised study (n = 167). Learner properties and attitude towards CBL were measured using psychometric scales, and knowledge by multiple-choice questions (pre- and post-test). RESULTS: Attitude towards CBL worsened in the CBL group (n = 70). Individual learners' properties did not explain this effect. The perceived programme quality was rated only 'average', which may contribute to the lower post-test values of attitude towards CBL. Learning outcomes were similar between the control group (n = 97) and students using CBL (n = 44). Learning efforts were shifted from self-study towards CBL. CONCLUSION: The initial enthusiasm of students was not maintained when using a programme designed to complement or even replace traditional teaching. Curriculum-wide implementation of CBL might be hampered by the discouragement of users.  相似文献   
50.
Vascular rings are usually repaired via left thoracotomy. We report our series of pediatric patients with vascular rings that were repaired thoracoscopically. From February 2002 to September 2004, 13 patients underwent video-assisted thoracoscopic surgical techniques (VATS) division of their vascular ring. Chest magnetic resonance arterography (MRA) and/or computed tomographic arteriography (CTA) were used to evaluate the vascular ring in most patients. Patients were chosen for VATS repair based on surgeon's choice and type of vascular ring. Data are expressed as mean +/- SD. The Children's Healthcare of Atlanta Institutional Review Board approved this retrospective chart review. Age and weight was 1.5 +/- 1.8 years (range: 4 months - 17 years) and 16.0 +/- 12.5 kg (range: 6.0 - 22.1 kg), respectively (n = 13). Associated diseases included congenital heart disease (n = 2). Symptoms included respiratory complaints (n = 6), dysphagia (n = 2), dysphagia and shortness of breath (n = 1), pneumonia (n = 2), tracheal deviation (n = 1), and one patient was asymptomatic. Vascular ring types included double aortic arch (n = 4) and right aortic arch with an aberrant left subclavian artery and a left ligamentum arteriosum (n = 9). Operating time was 70 +/- 20 minutes (range: 46 - 122 minutes). One patient had to be opened because of a large arch. Length of stay was 1.9 +/- 0.9 days (range: 1 - 3 days). There were no complications, and all patients improved clinically at follow-up. Thoracoscopic repair of certain types of vascular rings seems to be safe and effective in children. More patients, however, need to be studied.  相似文献   
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