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1.
We report a 20 month old female patient with diploid-triploid mixoploidy (46,XX/69,XXX) syndrome with hypothyroidism and precocious puberty. The triploid cell line was only expressed in the fibroblast culture and comprised the majority (95%) of the cells. Chromosome analysis of the fetal blood sample and peripheral blood sample were normal. The patient shows typical features of full triploidy (growth and severe mental retardation, cranial and facial dysmorphism, complete syndactyly of fingers 3/4, partial syndactyly of toes 2/3) and facial but no body asymmetry. At the age of 5 months central hypothyroidism and precocious puberty were diagnosed. Thin pigmented streaks were visible on the wrists and legs of the patient at the age of 16 months. This is the first patient reported so far with 46,XX/69,XXX mixoploidy suffering from hypothyroidism and precocious puberty.  相似文献   
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This report contains the experience of our centre, using the transvaginally guided puncture procedure, to reduce the number of fetuses in a multifetal pregnancy to a lower number. The aim of the procedure was to improve perinatal outcome and/or to meet the personal desires of patients and their families. We surveyed 148 multifetal pregnancy reductions. The fetus or fetuses overlying the internal os was most commonly reduced. The total uncorrected loss of the entire pregnancy was 13.4%. The corrected pregnancy loss was 11%. Of the 63 twins left after the reduction, 33 delivered preterm. Of the 36 singletons, two delivered preterm. Our conclusion was that multifetal pregnancy reduction is a safe procedure for the mother and has an acceptable loss rate of the entire pregnancy. The reduction of a fetus overlying the internal os by the transvaginal puncture procedure seems to yield results at least as good as the transabdominally performed puncture procedures for multifetal pregnancy reduction.  相似文献   
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AIM: Assessment of RAAS and vasopressin in patients with primary pulmonary hypertension (PPH). MATERIALS AND METHODS: Activity of plasma renin (APR), angiotensin-converting enzyme (ACE), plasma levels of angiotensin II (AII) and vasopressin (VP), serum concentration of aldosteron (AS) were measured by radioimmunoassay and enzyme immunoassay in 21 PPH patients with circulatory failure (age 34.7 +/- 2.1 years), 11 patients with NYHA functional class II-III, 10 with class IV, and 10 control subjects (age 29.8 +/- 1.5 years). RESULTS: Compared to controls, 21 PPH patients had elevated RAAS parameters: APR up to 3.52 ng/ml/h (p < 0.05), activity of ACE up to 43.13 units, AII level up to 33.93 ng/ml (p < 0.01), AS up to 468.86 ng/ml (p < 0.01), VP up to 5.26 ng/ml (p < 0.001). Circulatory failure progression resulted in activation of all the RAAS components. This and VP activation was the greatest in PPH patients with ACE > 5 ng/ml/h. PPH patients with mean pressure in the pulmonary artery higher than 60 mm Hg demonstrated higher ARP, AS, VP, AII, ACE than those who had this pressure under 60 mm Hg. CONCLUSION: PPH patients display a noticeable activation of RAAS and VP. This activation seems to be secondary as the changes increase with elevation of the pressure in the pulmonary artery and aggravation of circulatory insufficiency. Plasma renin activity determines the degree of RAAS activation as a whole. The discovered activation of RAAS in PPH gives grounds for doubts in the validity of using ACE inhibitors in the treatment of PPH.  相似文献   
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Abstract— One of the most annoying distortions in (auto)stereoscopic displays is probably cross‐talk, visible as double edges, which is mainly caused by an imperfect separation of left‐ and right‐eye images. For different types of three‐dimensional (3‐D) displays, cross‐talk is caused by different origins, which could result in different levels of perceived image distortion. To evaluate the influence of (auto)stereoscopic display technology on cross‐talk perception, optical measurements and subjective assessments were performed with three different types of 3‐D displays. It is shown with natural still images that the 3‐D display technology with the lowest luminance and contrast level tolerates the highest level of cross‐talk, while still maintaining an acceptable image‐quality level.  相似文献   
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Abstract— The influence of regional background on the visibility of sharpness differences has been investigated by blurring various still images to different extents. The assessment of sharpness has been performed both in China by Chinese people and in the Netherlands by European people. The results showed that both Chinese characters and Roman text were clearly more critical image material for judging sharpness than natural images. Independent on whether the image contained Chinese characters or Roman text, the visibility threshold for a difference in sharpness was the same for both the Chinese and European people. When related to a diagonal step response, the threshold on average equaled an angular resolution of 5 arcsec.  相似文献   
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