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The α and β subunits of human follitropin were isolated in a high state of purity. The tryptophan fluorescence of the native hormone and the isolated β subunit are different. The N-terminus of the α and β subunits was identified as valine and aspartic acid respectively. While recombination of the isolated α and β subunits restores the electrophoretic mobility of the intact hormone, its receptor binding activity cannot be fully regenerated. Substitution of the human follitropin α by an ovine lutropin α subunit, to form a recombinant with the follitropin β subunit, generates a complex with 2–3 receptor binding activity of the native human follitropin and the same activity as ovine follitropin. Acylation of the intact hormone does not disrupt the quaternary structure but leads to complete inactivation. Acylation studies with the subunits suggests the crucial role of the ?-amino groups of the α subunit in determining biological activity.  相似文献   
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Aims  Our aim was to examine intellectual development in children with congenital hemiplegia from early childhood to adolescence.
Method  Full-scale IQ (FIQ), Verbal IQ (VIQ), and Performance IQ (PIQ) scores were measured in 32 participants (19 males, 13 females) with congenital hemiplegia at mean ages of 4 years 6 months (SD 7mo; 31 participants), 7 years (SD 6mo; 23 participants), and 14 years (SD 1y 5mo; 26 participants).
Results  The FIQ and VIQ scores did not change with age, but the PIQ declined significantly (0.7 points per year; p =0.004). The estimated mean (95% confidence intervals) scores in males born at term with right-sided lesions without epilepsy were FIQ 106.5 (95.29–117.74), VIQ 105.9 (95.57–116.24), and PIQ 103.7 (93.19–114.31). Those means were negatively associated with preterm birth. PIQ was negatively associated with epilepsy. VIQ increased more quickly in males and in children with right-sided lesions.
Interpretation  The results confirm previous findings of FIQ stability, PIQ decline, the impact of epilepsy, and the status of females with left-sided lesions, and also reveal the effect of gestational age at birth. They underline the importance of management focused on nonverbal functions and further the debate about the early lateralization of language, the 'crowding effect', and the difference in brain plasticity between males and females.  相似文献   
264.
The mitochondrial electron transport chain (mtETC) consists of four multi-subunit enzyme complexes. Complex I or NADH:ubiquinone oxidoreductase, the largest mtETC multisubunit complex, consists of approximately 41 subunits. Seven of these subunits are encoded by the mitochondrial genome, the remainder by the nuclear genome. Among the mitochondriocytopathies, complex I deficiencies are encountered frequently. Although some complex I deficiencies have been associated with mitochondrial DNA mutations, the genetic defect has not been elucidated in the majority of complex I-deficient patients. It is expected that many of these patients have mutations in the nuclear- encoded subunits of this complex, so vital for cellular energy production. After a brief summary of the current knowledge of complex I from cow, bacteria and fungi, this review presents the state of the art of the knowledge of the human nuclear-encoded complex I genes which, in the last 18 months, has made enormous progress. At present, the complete gene structure of four subunits and the cDNA structure of 18 of the 34 complex I nuclear-encoded subunits are known. Mapping of these subunits shows a random distribution over the chromosomes. The chromosomal localization is known for 14 complex I genes. Recently, the first mutation, a 5 bp duplication in the 18 kDa (AQDQ) subunit, has been reported. We expect that within 1 year all human nuclear-encoded complex I subunits will be cloned. Mutational analysis of these subunits is warranted in complex I-deficient patients and will not only be important for genetic counselling but will also extend the knowledge regarding the functional properties of the individual human complex I subunits.   相似文献   
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Fifty-four adults with primary mesangial proliferative glomerulonephritisand IgM deposition were observed for a minimum of three yearsor until end-stage renal failure. The actuarial renal survivalwas 80 per cent at 5 years and 64 per cent at 10 years; multivariateanalysis identified microscopic haematuria, extent of mesangialproliferation and global glomerular sclerosis as independentprognostic indicators.  相似文献   
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目的 探讨ICU患者锁骨下静脉穿刺置管术(SVC)的操作及并发症发生情况.方法 回顾性分析2007年1 月至2011年12月接受SVC的257例ICU患者的临床资料.结果 穿刺成功率为98.1%,其中一次穿刺成功211例,重复穿刺成功41例,因患者血管变异或操作技术原因导致失败5例.并发症发生率12.1%,总计31例,其中导管尖端入颈内静脉12例,导管相关感染8例,皮下血肿6例,气胸3例,心律失常2例.结论 SVC成功率高,操作步骤易于掌握,对患者颈部及四肢活动影响小,导管保留时间较长,方便护理,感染概率低于颈内、股静脉置管.  相似文献   
270.
目的:观察并比较黑醋与红曲单用及联用对中国中老年人降低血脂的效能。方法:试验于2003-10/11在大连医科大学中日合作医药科学研究所进行。选择30名年龄为45 ̄65岁的中老年人。30名受试者被随机分为3组,每组10人,分别服用黑醋丸6粒,红曲丸6粒或黑醋 红曲丸6粒,1次/d,连续4周;3种膳食补充剂黑醋丸、红曲丸及黑醋 红曲丸由含有不同剂量的黑醋固形物、红曲粉末K-F、柠檬酸钠、大豆油、蜂蜡、脂肪酸甘油脂组成(由日本国第一药品工业株式会社提供)。各组服用剂量分别为每天黑醋固形物360mg,红曲粉72mg及黑醋固形物360mg 红曲粉72mg。服用2和(或)4周后,检测血脂和血糖,同时用血清样品检测肝功与肾功能。实验结果用SPSS统计软件进行方差分析。结果:30名中老年人全部进入结果分析。①受试者连续3d每日营养素摄入量:3组之间热量、胆固醇、膳食纤维、宏量或微量营养素摄入量差距均无显著性。②血清脂质浓度和计算的脂质比:2,4周血清三酰甘油含量,黑醋 红曲组低于基础值(分别下降(24.6±4.9)%,(27.6±3.4)%,P<0.05);红曲组与基础值比较,差异无显著性[分别下降(6.5±3.4)%,(11.6±4.5)%];黑醋组与基础值比较,差异无显著性[分别下降(10.2±7.3)%,(12.4±8.2)%]。2,4周血清胆固醇、低密度脂蛋白胆固醇含量,黑醋 红曲丸、红曲丸和黑醋丸组均比基础值降低,差异无统计学意义。3种膳食补充剂对血清高密度脂蛋白胆固醇及计算的脂质比值无明显改变。血糖含量无变化。未发现对受试对象产生明显不良反应。结论:服用黑醋 红曲丸能明显降低受试者血清三酰甘油含量。黑醋与红曲合用对高脂血症者可能有健康效益。  相似文献   
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