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81.
82.
Akanchha?Kesari Hanna?Rennert Debra?GB?Leonard Balraj?MittalEmail author 《BMC medical genetics》2005,6(1):22
Background
Spinal muscular atrophy (SMA) represents the second most common fatal autosomal recessive disorder after cystic fibrosis. Due to the high carrier frequency, the burden of this genetic disorder is very heavy in developing countries like India. As there is no cure or effective treatment, genetic counseling becomes very important in disease management. SMN1 dosage analysis results can be utilized for identifying carriers before offering prenatal diagnosis in the context of genetic counseling. 相似文献83.
Progesterone stimulates p42 extracellular signal-regulated kinase (p42erk) in human spermatozoa 总被引:1,自引:3,他引:1
Luconi M; Krausz C; Barni T; Vannelli GB; Forti G; Baldi E 《Molecular human reproduction》1998,4(3):251-258
Mitogen-activated protein kinases (MAPK), also known as extracellular
signal-regulated kinases (ERKs) are cytoplasmic and nuclear
serine/threonine kinases involved in signal transduction of several
extracellular effectors. Recently, we have demonstrated that ERKs are
present in spermatozoa and are involved in the regulation of the process of
capacitation. We report here the effect of progesterone, a well-known
inducer of the acrosome reaction in mammalian spermatozoa, on the
immunolocalization, phosphorylation and activity of ERKs in capacitated
human spermatozoa. We demonstrated that short-term incubation of
spermatozoa with progesterone induces phosphorylation and activation of
ERKs, resulting in redistribution of the proteins from the post-acrosomal
region to the equatorial segment within the sperm head. To investigate the
role of ERKs on the biological effects of progesterone, we used the MAPK
cascade inhibitor PD098059, which strongly inhibited progesterone-induced
activation of ERK-2. This compound did not inhibit progesterone-induced
acrosome reaction, although it prevented redistribution of the enzyme to
the equatorial region of the sperm head. These results suggest that the two
processes, although temporally related, are independent. In conclusion, we
provide new insight into the signal transduction pathways involved in the
non- genomic action of progesterone in spermatozoa and suggest a possible
involvement of ERKs in the process of fertilization.
相似文献
84.
组织工程注射骨的体外实验研究 总被引:1,自引:0,他引:1
目的 :探索骨髓间充质细胞在纤维胶内体外成骨的可行性。方法 :5× 10 6~ 10× 10 6细胞 /毫升的骨髓间充质细胞植入前行细胞活力测定 ;植入纤维胶 ,体外培养 60 d后进行组织学、免疫组织化学分析。结果 :细胞在纤维胶内产生大量的特异性 型胶原 ,并有大量的钙质沉着。结论 :骨髓间充质细胞在纤维胶内可在体外培养的环境下生成大量的骨基质。 相似文献
85.
补中益气汤对环磷酰胺致骨质疏松小鼠骨生物力学的影响 总被引:4,自引:0,他引:4
目的:观察环磷酰胺对小鼠骨生物力学的影响,观察补中益气汤和葡萄糖酸钙对环磷酰胺造成的小鼠骨质疏松的防治作用。方法:实验于2005-10/2006-01在广东医学院药理教研室完成。选取昆明种小鼠40只,体质量(20±2)g,雌雄各半,按体质量对等原则随机分为4组,正常对照组、环磷酰胺模型组、环磷酰胺合用补中益气汤组、环磷酰胺合用葡萄糖酸钙组,每组10只。补中益气汤的制备:称取炙黄芪200g,党参60g,炙甘草100g,白术60g,当归60g,升麻60g,柴胡60g,陈皮60g,切碎,加水煎煮2次,滤过,滤液浓缩至1700mL,冰箱保存备用。正常对照组灌胃给予生理盐水10mL/(kg·d),环磷酰胺模型组灌胃给予环磷酰胺20mg/(kg·d);环磷酰胺合用补中益气汤组灌胃给予环磷酰胺20mg/(kg·d)的同时灌胃给予补中益气汤20mL/(kg·d);环磷酰胺合用葡萄糖酸钙组灌胃给予环磷酰胺20mg/(kg·d)的同时灌胃给予葡萄糖酸钙0.5mg/(kg·d)。均自由饮水和进食标准饲料。于实验第30天称质量后,处死动物,取肝脏、脾脏、胸腺称质量,根据动物体质量计算器官指数,同时取右侧股骨供骨生物力学测定用。结果:40只小鼠均进入结果分析。与正常对照组比较,环磷酰胺模型组骨生物力学指标最大载荷、弹性载荷、刚度系数均减少[(12.11±2.06)N,(8.15±2.57)N,(45.89±6.33)N/mm;(14.98±1.54)N,(10.17±1.17)N,(56.34±9.49)N/mm,P<0.05,P<0.01]。与环磷酰胺模型组比较,环磷酰胺合用补中益气汤组、环磷酰胺合用葡萄糖酸钙组生物力学指标最大载荷、刚度系数增高[环磷酰胺模型组:(12.11±2.06)N,(45.89±6.33)N/mm;环磷酰胺合用补中益气汤组:(15.52±2.67)N,(57.68±11.19)N/mm;环磷酰胺合用葡萄糖酸钙组:(17.10±2.96)N,(63.69±11.11)N/mm,P<0.05,P<0.01]。与环磷酰胺合用葡萄糖酸钙组比较,环磷酰胺合用补中益气组表现为各生物力学指标与环磷酰胺合用葡萄糖酸钙组相似,差异无显著性意义。结论:环磷酰胺能使小鼠骨结构性质和材料性质下降,补中益气汤和葡萄糖酸钙均能对抗环磷酰胺导致的骨质量下降,预防骨质疏松。 相似文献
86.
Marks GB Mihrshahi S Kemp AS 《英国医学杂志》2007,10(3):173-174
问题:在出生后的最初5年,减少房屋尘螨(HDM)变应原暴露并改变饮食中脂肪酸构成是否可以降低5岁时发生哮喘的风险? 相似文献
87.
Trojano M Liguori M Paolicelli D Zimatore GB De Robertis F Avolio C Giuliani F Fuiani A Livrea P;Southern Italy MS Group 《Multiple sclerosis (Houndmills, Basingstoke, England)》2003,9(5):451-457
This independent, population-based surveillance study monitored the efficacy and safety of interferon beta (IFNbeta) products in 1033 patients with relapsing-remitting multiple sclerosis (RRMS) from 15 centres in Italy. Relapses, Expanded Disability Status Scale (EDSS) scores, and adverse events were evaluated for up to 24 months. Data of patients with a baseline EDSS score < or = 3.5 are reported. The proportions of relapse-free patients were similar among the groups at 12 and 24 months (P = 0.10). IFNbeta products produced significant reductions from baseline in relapse rates at 12 and 24 months (P < 0.001), with no differences among treatments (P = 0.2). There were no significant differences in mean EDSS change among groups at 12 or 24 months. The IFNbeta-1b group showed a higher incidence of adverse events during the first year of treatment (P < 0.05) than IFNbeta-1a groups, and more withdrawals (10%) compared with Avonex (5%) at 24 months. IFNbeta products are equally effective in low disability RRMS, but IFNbeta-1a may have a more favorable efficacy/tolerability ratio. 相似文献
88.
P-31 MR spectroscopy of normal human brain and brain tumors 总被引:2,自引:0,他引:2
Hubesch B; Sappey-Marinier D; Roth K; Meyerhoff DJ; Matson GB; Weiner MW 《Radiology》1990,174(2):401-409
Image-guided phosphorus-31 magnetic resonance (MR)-localized image-selected in vivo spectroscopy was performed on normal human brain and brain tumors. Peak area ratios, absolute molar concentrations of metabolites, and pH were determined. T1 values in normal brain were measured. The most important finding was that the metabolite concentrations detectable with MR spectroscopy in brain tumors were reduced from 20% to 70%. Phosphomonoesters, phosphodiesters, and phosphocreatine (PCr) showed the greatest decreases, while inorganic phosphate (Pi) showed the least change. The PCr-Pi ratio was significantly reduced in tumors. The pH of brain tumors (7.12 +/- 0.03) was more alkaline than that of normal brain (6.99 +/- 0.01). The authors conclude that the metabolite concentrations and pH in human brain tumors differ significantly from those in normal brain. These differences may be ultimately useful in characterizing tumors in man. 相似文献
89.
90.