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21.
Charcot-Marie-Tooth disease (CMT) is a heterogeneous disorder and is traditionally classified into two major types, CMT type 1 (CMT1) and CMT type 2 (CMT2). Most CMT1 patients are associated with the duplication of 17p11.2-p12 (CMT1A duplication) and small numbers of patients have mutations of the peripheral myelin protein 22 (PMP22), myelin protein zero (MPZ), connexin 32 (Cx32/GJB1), and early growth response 2 (EGR2) genes. Some mutations of MPZ and Cx32 were also associated with the clinical CMT2 phenotype. We constructed denaturing gradient gel electrophoresis (DGGE) analysis as a screening method for PMP22, MPZ, and Cx32 mutations and studied 161 CMT patients without CMT1A duplication. We detected 27 mutations of three genes including 15 novel mutations; six of PMP22, three of MPZ, and six of Cx32. We finally identified 21 causative mutations in 22 unrelated patients and five polymorphic mutations. Eighteen of 22 patients carrying PMP22, MPZ, or Cx32 mutations presented with CMT1 and four of them with MPZ or Cx32 mutations presented with the CMT2 phenotype. DGGE analysis was sensitive for screening for those gene mutations, but causative gene mutation was not identified in many of the Japanese patients with CMT, especially with CMT1. Other candidate genes should be studied to elucidate the genetic basis of Japanese CMT patients. 相似文献
22.
目的总结膝关节置换术后骨密度的变化及其诊断方式、影响因素和药物防治研究进展。方法查阅近年国内外有关文献,对骨密度评估测量方式的优缺点、膝关节置换术后骨密度的变化趋势及其影响因素,以及药物防治疗效差异进行总结。结果膝关节置换术后全身骨密度及假体周围平均骨密度总体呈下降趋势,与检测时患者体位、年龄、体质量、日常活动、假体固定方式、假体设计以及假体材料等因素密切相关。狄诺塞麦、双膦酸盐和特立帕肽等药物能够减少膝关节置换术后骨密度降低程度。结论膝关节置换术后骨密度呈下降趋势,但发生机制尚不明确,与多种因素相关。目前,抑制骨吸收药物对于膝关节置换术后骨密度降低有一定效果,但远期疗效有待进一步探究。 相似文献
23.
Joel P. Bish Akshay Pendyal Lijun Ding Heather Ferrante Vy Nguyen Donna McDonald-McGinn Elaine Zackai Tony J. Simon 《Neuroscience letters》2006
Children with chromosome 22q11.2 deletion syndrome commonly are found to have morphological brain changes, cognitive impairments, and elevated rates of psychopathology. One of the most commonly and consistently reported brain changes is reduced cerebellar volume. Here, we demonstrate that, in addition to the global cerebellum reductions previously reported, volumetric reductions of the anterior lobule and the vermal region of the neo-cerebellum in the mid-sagittal plane best differentiate children with the deletion from typically developing children. These results suggest that the morphological changes of specific portions of the cerebellum may be an important underlying substrate of cognitive impairments and increased incidence of psychopathology in this group. 相似文献
24.
L. J. Butler A. V. Palmer T. Spencer R. Tabios-Broadway W. J. Wall 《Clinical genetics》1987,31(4):199-205
A female child is described with multiple anomalies including epicanthus, frontal bossing, short sternum, polydactyly, cleft of the larynx, renal cysts, and unusual dermatoglyphics. She died aged 3 months and was found to have a unique de novo deletion of chromosome No. 4 (q22-q25). This case is compared with other long arm deletions of 4q and reference made to assignment of genetic markers to chromosome No. 4. 相似文献
25.
Three children are reported with typical cat eye syndrome (CES) and three more children with partial CES because of absence of coloboma, in which the supernumerary marker chromosome was studied by FISH. Using a genomic library, and also a centromeric and particularly a cosmid probe of 22q11, partial tetrasomy was shown in all cases. 相似文献
26.
5-Fu佐剂包裹物的抗肿瘤作用的实验研究 总被引:3,自引:0,他引:3
本文作了福氏完全佐剂(Freund’scompleteadjuvant,FCA)包裹5-Fu的抗肿瘤作用的实验研究。在对小鼠S180肿瘤(腹水型),EAC肿瘤(腹水型)及H22肝癌(腹水型)荷瘤鼠的治疗实验中,一次性腹腔注射2mg~6mg的5-Fu(相当于70公斤人给予778~2334mg的剂量)均不能显著延长荷瘤鼠的存活期,盐水FCA亦无治疗作用,而5-FuFCA却显示出显著的治疗效果。4次实验,5-FU-FCA治疗组荷瘤鼠平均存活期30.6天~48.3天,均显著长于同次实验的各对照组,且每次实验都有2/8至3/8的荷瘤鼠可完全治愈。 相似文献
27.
28.
《Seminars in Pediatric Surgery》2022,31(3):151181
Advancements in donor management, organ preservation and operative techniques, as well as immunosuppressive therapies, have provided children with intestinal failure and its complications a chance not only for enteral autonomy but also long-term survival through intestinal transplantation (ITx). First described in the 1960’s, experience has grown in managing these complex patients both pre- and post-transplant. The goals of this review are to provide a brief history of intestinal transplantation and intestinal rehabilitation in pediatric patients, followed by focused discussions of the indications for ITx, induction and maintenance immunosuppression therapies, common post-operative complications, and outcomes/quality of life post-transplant. 相似文献
29.
E. Arroyo L. Prieto J. M. Ruiz de la Cuesta F. García-Sánchez J. L. Vicario 《International journal of legal medicine》1996,109(2):98-99
The fragment length polymorphism YNZ22 (D17S5) was analysed for a sample of 207 unrelated individuals living in Madrid (Spanish Caucasians) using PCR-methodology and high resolution separation. Hardy-Weinberg expectations (HWE) were calculated after pooling alleles into four groups. No deviations from HWE were detectable using the conventional 2-test. The power of discrimination was estimated as 0.96 and the mean paternity exclusion chance as 0.7587. A comparison of the allele frequency distribution with those of other Caucasian groups revealed no major differences. 相似文献
30.
Summary Radiotracer techniques capable of measuring norepinephrine clearance and spillover rate into plasma were used to test the hypothesis that the antihypertensive effects of propranolol and atenolol in conscious spontaneously hypertensive rats are associated with an inhibition of norepinephrine release from postganglionic sympathetic neurons. The 10%–15% fall in mean arterial pressure produced over 4 h by propranolol (1, 3.3 and 10 mg/kg, s. c.) and atenolol (1, 3.3 and 10 mg/kg, s. c.) was not dose-related, and only the largest dose of propranolol caused a significant bradycardia. Each dose of atenolol significantly lowered heart rate. The decrease in blood pressure caused by propranolol and atenolol was not related to the decrease in heart rate. Both propranolol and atenolol inhibited norepinephrine clearance by 12% to 16%. The 1 mg/kg doses of propranolol and atenolol significantly suppressed norepinephrine spillover rate by 21 % and 32%, respectively, at 4 h postinjection. As the dose of propranolol was increased, the inhibition of norepinephrine spillover was reversed as plasma epinephrine concentration rose by 125%. The suppression of norepinephrine spillover rate caused by atenolol was more persistent but did diminish after the 10 mg/kg dose, when plasma epinephrine concentration was elevated by 55%. Both drugs suppressed plasma renin concentration, but the inhibition of norepinephrine spillover rate by propranolol and atenolol was not related to the fall in plasma renin concentration. By comparison, treatment with the adrenergic neuron blocking agent bretylium (5, 10, 20 and 40 mg/kg, s. c.) elicited a dose-related vasodepression with no change in heart rate or plasma renin concentration. The 10 mg/kg dose of bretylium inhibited norepinephrine spillover rate by 40%, but increasing the dose did not produce a further suppression of norepinephrine spillover rate. Bretylium caused a dose-related elevation of plasma epinephrine concentration (354% increase at 40 mg/kg). In a separate study, propranolol (10 mg/kg) and bretylium (40 mg/kg) significantly increased epinephrine spillover rate by 85% and 118%, respectively. Based on these data, we conclude that the -adrenoceptor antagonists lower blood pressure by inhibiting norepinephrine release from postganglionic sympathetic neurons.
Send offprint requests to T. K. Keeton at the above address 相似文献