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Severe aortic regurgitation was discovered in a young man 21 days after blunt chest trauma and after a prolonged febrile state with positive blood cultures. Using transoesophageal echocardiography (TEE), it was possible to make the differential diagnosis between traumatic rupture and endocarditis as the cause of valvular insufficiency. The use of TEE in the initial evaluation of severe thoracic trauma with an unclear clinical picture is recommended. This method is easy to use at the bedside and gives precise information on the aortic valve and the ascending aorta.  相似文献   
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Clinical and histological patterns of dermatofibromas of the nail apparatus   总被引:1,自引:0,他引:1  
True fibromas develop as painless slow-growing nodular tumours. They may appear in any portion of the nail apparatus. The clinical features vary according to their anatomical site. In contrast, the histological features, consisting of a dermal hypocellular reticular nodule with ill-defined demarcation, were similar in all our patients, and factor XIIIa was negative.  相似文献   
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Diarrhea is the most frequently reported adverse event in patients treated with mycophenolate mofetil. Twenty-six renal transplant patients on a mycophenolate mofetil-based immunosuppressive regime with persistent afebrile diarrhea were examined. Diarrhea caused a significant rise in FK-506 trough levels despite intake of stable doses, necessitating FK-506 dose reductions of 30% to obtain pre-diarrhea trough levels. In contrast, trough levels of cyclosporine A remained stable without dose adjustments. This suggests that absorption and/or metabolism is differentially altered for FK506 compared with cyclosporine A in patients with diarrhea. In nine patients mycophenolate mofetil was reduced or stopped because of persistent diarrhea without identifiable cause. This resulted in end-stage renal disease because of chronic rejection in two patients, and in acute rejection in two patients, all taking FK506 and steroids. Therefore, dose adjustments of FK506 in patients with diarrhea must be carefully monitored, especially when doses of mycophenolate mofetil are also reduced.  相似文献   
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X-linked spinal and bulbar muscular atrophy (SBMA) is caused by a CAG repeat expansion in the first exon of the androgen receptor (AR) gene. Disease-associated alleles (37-66 CAGs) change in length when transmitted from parents to offspring, with a significantly greater tendency to shift size when inherited paternally. As transgenic mice carrying human AR cDNAs with 45 and 66 CAG repeats do not display repeat instability, we attempted to model trinucleotide repeat instability by generating transgenic mice with yeast artificial chromosomes (YACs) carrying AR CAG repeat expansions in their genomic context. Studies of independent lines of AR YAC transgenic mice with CAG 45 alleles reveal intergenerational instability at an overall rate of approximately 10%. We also find that the 45 CAG repeat tracts are significantly more unstable with maternal transmission and as the transmitting mother ages. Of all the CAG/CTG repeat transgenic mice produced to date the AR YAC CAG 45 mice are unstable with the smallest trinucleotide repeat mutations, suggesting that the length threshold for repeat instability in the mouse may be lowered by including the appropriate flanking human DNA sequences. By sequence-tagged site content analysis and long range mapping we determined that one unstable transgenic line has integrated an approximately 70 kb segment of the AR locus due to fragmentation of the AR YAC. Identification of the cis - acting elements that permit CAG tract instability and the trans -acting factors that modulate repeat instability in the AR YAC CAG 45 mice may provide insights into the molecular basis of trinucleotide repeat instability in humans.   相似文献   
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Our study justified by the frequency of acute appendicitis and the possibility of anatomic variations of the caecoappendicular area attempt to index the topographic variations of the vermiform appendix (v.a.). On 80 fresh native cadavers (62 men and 18 women) without surgical antecedent whose mean age was 36 years (range between 16 and 78 years) we note the morphotype and the height. More over we study the intraperitoneal projection of the Mac Burney point, topography and shape of the cecum and the situation, shape and dimensions of the v.a. We note also the level of implantation of this latter on the cecum, appearance of the mesoappendix and the distance separating the base of the appendix to the ileo-caecal junction. Mac Burney's point permitted to localize appendix in 66%; the cecum has more often than not the form of a bulb (98.7%) and sited in right fossa iliaca. We noted 7 types of topographic disposition; front varieties were more frequent (68.7%) notably the pelvic direction (51.2%) with a medial (72.5%) or a posteromedial (27.5%) establishment on the cecum. The v.a. was more often in the form of worm with a long mesoappendix; his mean length was 106.4 mm (between 65 and 160 mm) and the mean diameter 6.77 mm (range between 4 and 10 mm). The distance which separated the base of the appendix to the ileo-cecal junction varied between 15 to 40 mm with a mean distance of 24.2 mm. Thus in this study, dimensions of the v.a. were very variables. Located in right fossa iliaca he adopted a front topography with pelvic direction and medial establishment on bulbar cecum. In spite of scarcity of ectopic situation of the appendix for which laparoscopic approach is salutary, a similar topographic study during surgical treatment of acute appendicitis will be interesting.  相似文献   
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Ciliary neurotrophic factor (CNTF) administration reduces weight in leptin-resistant mice via the signalling pathway normally activated by leptin. A G>A null mutation in the CNTF gene results in complete absence of protein. We hypothesised that absence of CNTF could lead to diminished initiation of anorectic pathways, with consequent increase in body mass. In 575 Caucasian men aged 59-73 years, the A/A genotype (frequency 1.9%) was associated with a 10 kg increase in weight (P=0.03, 2 df) and 3 kg/m(2) greater BMI (P=0.02, 2 df). There was no effect in women. The CNTF G>A null mutation therefore confers a moderate effect on obesity in males of A/A genotype, who represent 1% of the general population.  相似文献   
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