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101.
Survival analysis of reaching EDSS ≥4.0 based on RoAD score ≥4 (dashed line) and <4 (solid line) by Cox regression analysis. (A) Unadjusted regression analysis. (B) Regression controlled for sex and immunotherapy groups, and the trajectory of treatment changes during follow‐up.  相似文献   
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Achondroplasia is a rare genetic disorder resulting in short‐limb skeletal dysplasia. We present the largest European population‐based epidemiological study to date using data provided by the European Surveillance of Congenital Anomalies (EUROCAT) network. All cases of achondroplasia notified to 28 EUROCAT registries (1991–2015) were included in the study. Prevalence, birth outcomes, prenatal diagnosis, associated anomalies, and the impact of paternal and maternal age on de novo achondroplasia were presented. The study population consisted of 434 achondroplasia cases with a prevalence of 3.72 per 100,000 births (95%CIs: 3.14–4.39). There were 350 live births, 82 terminations of pregnancy after prenatal diagnosis, and two fetal deaths. The prenatal detection rate was significantly higher in recent years (71% in 2011–2015 vs. 36% in 1991–1995). Major associated congenital anomalies were present in 10% of cases. About 20% of cases were familial. After adjusting for maternal age, fathers >34 years had a significantly higher risk of having infants with de novo achondroplasia than younger fathers. Prevalence was stable over time, but regional differences were observed. All pregnancy outcomes were included in the prevalence estimate with 80.6% being live born. The study confirmed the increased risk for older fathers of having infants with de novo achondroplasia.  相似文献   
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We intended to establish a pharmacologic concept of synergistic antiproliferative effects on smooth muscle cells (SMC) by using paclitaxel and cyclosporine A at clinically applicable doses. Coronary SMC were incubated with paclitaxel and cyclosporine A at concentrations of 10 – 20 nmol/L and 83 – 415 nmol/L, respectively. Antiproliferative effects were assessed by cell counts, [3H]thymidine incorporation and cell cycle analysis. In addition, apoptosis was studied by cytoplasmic histone-associated DNA fragments and in vitro protein kinase C activity (PKC) was determined by immunoassay. We found paclitaxel and cyclosporine A to exert a highly supra-additive antiproliferative effect on SMC with significant reductions of cell counts (p < 0.01) and [3H]thymidine incorporation (p < 0.05). SMC were found to be arrested at the G2/M transition. This antiproliferative effect was observed in the absence of DNA fragmentation above values obtained for single compound treatment, which had virtually no impact on cell proliferation. DNA fragmentation started to increase at a drug combination comprising paclitaxel at the higher dose of 20 nmol/L. Under the treatment with both paclitaxel and cyclosporine A, PKC activity showed a 1.8-fold increase (p < 0.05) compared with untreated controls. In conclusion, PKC mediates supra-additive antiproliferative effects of paclitaxel and cyclosporine A on SMC. The data demonstrate a highly efficient pharmacologic concept for the inhibition of SMC proliferation. Further studies are needed to test this concept under in vivo conditions for the prevention of restenosis or transplant vasculopathy by systemic application of cyclosporine A – when already applied for immunosuppressive purposes – and local delivery of paclitaxel. Received: 28 August 2001, Returned for revision: 25 September 2001, Revision received: 20 November 2001, Accepted: 4 December 2001  相似文献   
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Linear and whorled nevoid hypermelanosis (LWNH) is characterized by hyperpigmented reticulate macules in a Blaschko linear arrangement without atrophy or preceding inflammation. Underlying chromosomal mosaicism was often assumed, but has been verified in only a few published cases. We report a 7-year-old boy with LWNH associated with congenital ventricular septal defect and psychomotor retardation. Prenatal chromosomal analysis of amniocytes revealed trisomy 20 mosaicism, which was not confirmed in peripheral blood lymphocytes after birth. Histologic sections of skin biopsy specimens taken at age 6 years showed hyperpigmentation of the basal epidermal layer with prominent melanocytes and isolated melanophages in the upper dermis. Cytogenetic analysis of cultured skin fibroblasts revealed an extra chromosome 20 in 5 of the 30 metaphases studied (17%). Mosaic trisomy 20 is one of the most common autosomal mosaicisms identified in amniocytes and is, as a rule, compatible with normal pregnancy outcome. In postnatal analysis of peripheral blood lymphocytes, an extra chromosome 20 could never be detected. However, when confirmed in skin fibroblasts, trisomy 20 mosaicism may be associated with systemic anomalies. The present case shows for the first time an association of LWNH with trisomy 20 mosaicism and emphasizes the importance of analyzing skin fibroblasts in cases of prenatally diagnosed trisomy 20.  相似文献   
110.
Quantification of magnetic resonance spectroscopy signals using the phantom replacement method requires an adequate correction of differences between the acquisition of the reference signal in the phantom and the measurement in vivo. Applying the principle of reciprocity, sensitivity differences can be corrected at low field strength by measuring the RF transmitter gain needed to obtain a certain flip angle in the measured volume. However, at higher field strength the transmit sensitivity may vary from the reception sensitivity, which leads to wrongly estimated concentrations. To address this issue, a quantification approach based on the principle of reciprocity for use at 3T is proposed and validated thoroughly. In this approach, the RF transmitter gain is determined automatically using a volume‐selective power optimization and complemented with information from relative reception sensitivity maps derived from contrast‐minimized images to correct differences in transmission and reception sensitivity. In this way, a reliable measure of the local sensitivity was obtained. The proposed method is used to derive in vivo concentrations of brain metabolites and tissue water in two studies with different coil sets in a total of 40 healthy volunteers. Resulting molar concentrations are compared with results using internal water referencing (IWR) and Electric REference To access In vivo Concentrations (ERETIC). With the proposed method, changes in coil loading and regional sensitivity due to B1 inhomogeneities are successfully corrected, as demonstrated in phantom and in vivo measurements. For the tissue water content, coefficients of variation between 2% and 3.5% were obtained (0.6–1.4% in a single subject). The coefficients of variation of the three major metabolites ranged from 3.4–14.5%. In general, the derived concentrations agree well with values estimated with IWR. Hence, the presented method is a valuable alternative for IWR, without the need for additional hardware such as ERETIC and with potential advantages in diseased tissue.  相似文献   
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