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11.
Factors involved in the stability of trinucleotide repeats during transmission were studied in 139 families in which a full mutation, premutation or intermediate allele at either FRAXA or FRAXE was segregating. The transmission of alleles at FRAXA, FRAXE and four microsatellite loci were recorded for all individuals. Instability within the minimal and common ranges (0-40 repeats for FRAXA, 0-30 repeats for FRAXE) was extremely rare; only one example was observed, an increased in size at FRAXA from 29 to 39 repeats. Four FRAXA and three FRAXE alleles in the intermediate range (41-60) repeats for FRAXA, 31-60 for FRAXE) were unstably transmitted. Instability was more frequent for FRAXA intermediate alleles that had a tract of pure CGG greater than 37 although instability only occurred in two of 13 such transmissions: the changes observed were limited to only one or two repeats. Premutation FRAXA alleles over 100 repeats expanded to a full mutation during female transmission in 100% of cases, in agreement with other published series. There was no clear correlation between haplotype and probability of expansion of FRAXA premutations. Instability at FRAXA or FRAXE was more often observed in conjunction with a second instability at an independent locus suggesting genomic instability as a possible mechanism by which at least some FRAXA and FRAXE mutations arise.   相似文献   
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目的研究神经干细胞(NSCs)移植对大鼠脊髓损伤(SCI)后红核神经元的作用。方法5-溴脱氧尿嘧啶核苷(BrdU)法标记处于对数生长期的NSCs,采用电控脊髓损伤打击装置制作大鼠脊髓损伤模型。实验分为3组:NSCs组、SCI组和假手术组(Sham组)。SCI后3 d进行NSCs移植,用免疫组化法观察移植细胞的存活及迁移情况,用辣根过氧化物酶(HRP)逆行示踪技术标记红核神经元,并用四甲基联苯胺(TMB)呈色反应显示红核脊髓束神经元的存活情况,用行为学(BBB)评分法观察大鼠瘫痪肢体的恢复情况。结果在损伤脊髓区域可检测到BrdU标记的阳性NSCs,中脑HRP标记红核神经元数目明显多于SCI组(P<0.01),BBB评分亦明显高于SCI组(P<0.01)。结论体外培养的胚胎大鼠NSCs在移植到脊髓损伤区域后可存活和迁移,对SCI后中脑红核神经元具有保护作用,从而促进了大鼠肢体功能的恢复。  相似文献   
13.

Background/purpose

The introduction of the piggyback technique for reconstruction of the liver outflow in reduced-size liver transplants for pediatric patients has increased the incidence of hepatic venous outflow block (HVOB). Here, we proposed a new technique for hepatic venous reconstruction in pediatric living-donor liver transplantation.

Methods

Three techniques were used: direct anastomosis of the orifice of the donor hepatic veins and the orifice of the recipient hepatic veins (group 1); triangular anastomosis after creating a wide triangular orifice in the recipient inferior vena cava at the confluence of all the hepatic veins (group 2); and a new technique, which is a wide longitudinal anastomosis performed at the anterior wall of the inferior vena cava (group 3).

Results

In groups 1 and 2, the incidences of HVOB were 27.7% and 5.7%, respectively. In group 3, no patient presented HVOB (P = .001). No difference was noted between groups 2 and 3.

Conclusions

Hepatic venous reconstruction in pediatric living-donor liver transplantation must be preferentially performed by using a wide longitudinal incision at the anterior wall of the recipient inferior vena cava. As an alternative technique, triangulation of the recipient inferior vena cava, including the orifices of the 3 hepatic veins, may be used.  相似文献   
14.

Background/Purpose

Living donor liver transplantation has become a cornerstone for the treatment of children with end-stage hepatic dysfunction, especially within populations or countries with low rates of organ utilization from deceased donors. The objective is to report our experience with 185 living donors operated on by a team pediatric surgeons in a tertiary center for pediatric liver transplantation.

Methods

Retrospective analysis of medical records of donors of hepatic grafts for transplant undergoing surgery between June 1998 and March 2013.

Results

Over the last 14 years, 185 liver transplants were performed in pediatric recipients of grafts from living donors. Among the donors, 166 left lateral segments (89.7%), 18 left lobes without the caudate lobe (9.7%) and 1 right lobe (0.5%) were harvested. The donor age ranged from 16 to 53 years, and the weight ranged from 47 to 106 kg. In 10 donors, an additional graft of the donor inferior mesenteric vein was harvested to substitute for a hypoplastic recipient portal vein. The transfusion of blood products was required in 15 donors (8.1%). The mean hospital stay was 5 days. No deaths occurred, but complications were identified in 23 patients (12.4%): 9 patients experienced abdominal pain and severe gastrointestinal symptoms and 3 patients required reoperations. Eight donors presented with minor bile leaks that were treated conservatively, and 3 patients developed extra-peritoneal infections (1 wound collection, 1 phlebitis and 1 pneumonia). Eight grafts (4.3%) showed primary dysfunction resulting in recipient death (3 cases of fulminant hepatitis, 1 patient with metabolic disease, 1 patient with Alagille syndrome and 3 cases of biliary atresia in infants under 1 year old). There was no relation between donor complications and primary graft dysfunction (P = 0.6).

Conclusions

Living donor transplantation is safe for the donor and presents a low morbidity. The donor surgery may be performed by a team of trained pediatric surgeons.  相似文献   
15.
We describe three patients who had typical features of hairy cell leukemia (HCL) and multiple myeloma (MM) at the same time. In two, both diagnoses were made within a short period of time, and in the third, HCL had been present for 2 yr before the appearance of a paraprotein, bone lesions, and plasma-cell infiltrates established the diagnosis of MM. Although this association has not been previously reported, cases of HCL with osteolytic lesions or a paraprotein band have been described. The cases described may represent clinical manifestations of closely related disorders arising from divergent differentiation from a common B-cell precursor rather than a chance association.  相似文献   
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Cystic fibrosis is frequently accompanied by a catabolic condition with low body mass index caused by a number of disease complications. Insulin-like growth factor-I (IGF-I) is an anabolic hormone and an important marker of nutritional status, liver function, and linear growth. Available data on IGF-I in cystic fibrosis are sparse and conflicting. From 1990-3, 235 of our 240 patients (114 males, 121 females, median age 16.2 years, ranged 0.1-44.0 years) had IGF-I measured once by radioimmunoassay. IGF-I was significantly reduced compared with a healthy Scandinavian control population: mean (-2 SD to +2 SD) IGF-I SD score was -0.97 (-3.7 to 1.7) in males and -0.67 (-3.2 to 1.9) in females. Height SD score was -0.95 (-3.3 to 1.4) in males and -0.81 (-3.2 to 1.6) in females. In patients who were still in the growth period a significant correlation of IGF-I SD score to height SD score (r = 0.28, p < 0.001) was found. The low IGF-I concentrations may reflect the catabolic state of many patients with cystic fibrosis and play a part in their abnormal growth pattern.  相似文献   
18.
The efficacy of high-dose chemotherapy (HDC) and circulating progenitor cell (CPC) transplantation in metastatic breast cancer (MBC) relies mainly on giving this treatment after a response to conventional induction chemotherapy has been achieved. For this reason an optimal mobilization regimen should be therapeutically effective while minimizing the number of leucaphereses required to support the myeloablative therapy. The combination of an anthracycline and paclitaxel in chemotherapy-untreated MBC has produced impressive response rates. We evaluated the CPC-mobilizing capacity of the combination epirubicin (90 mg m(-2)) and paclitaxel (135 mg m(-2)) followed by filgrastim (5 microg kg(-1) day(-1)) starting 48 h after chemotherapy administration in ten patients with MBC who were eligible for an HDC and CPC transplantation programme. Leucaphereses were performed by processing at least two blood volumes per procedure at recovery from neutrophil nadir when CD34+ cells in the peripheral blood exceeded 20 microl(-1). In most patients (six out of 10) more than 2.5 x 10(6) CD34+ cells kg(-1), a threshold considered to be sufficient for haematopoietic reconstitution, were collected with a single apheresis. In the remaining four patients an additional procedure, performed the following day, was enough to reach the required number of progenitors. These data suggest that the epirubicin-paclitaxel combination, besides being a very active regimen in MBC, is effective in releasing large amounts of progenitor cells into circulation.  相似文献   
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