起始密码下游序列与16srRNA3′端序列的匹配性对基因表达效率的影响

目的 :研究起始密码下游序列与 16srRNA 3′端 +146 9——— +1482局部序列间的匹配关系对基因表达效率的影响。方法 :我们一方面对人IL_2、人IL_8、人IL_6 ,人GM_CSF、人G_CSF、人IL_1ra、人IL_9等全长cDNA序列及 5′末端局部序列与 16srRNA 3′端 +146 9——— +1482序列进行匹配性进行分析 ,寻找序列匹配性与表达效率间的关系 ;另一方面 ,对人IL_6、人GM_CSFcDNA 5′端序列进行沉默突变 ,增强其与 16srRNA 3′端 +146 9——— +1482序列间的匹配性 ,并克隆入pKpL4表达型质粒载体 ,通过大肠杆菌进行表达 ,实验验证序列匹配性与基因表达效率的关系。结果 :分析发现起始密码下游局部序列与 16srRNA 3′端 +146 9——— +1482核酸匹配性越好 ,则目的蛋白表达效率越高 ;目的基因编码区内与 16srRNA 3′ +146 9——— +1482间的最大匹配区域越靠近 5′末端 ,目的蛋白表达效率越高。通过对人IL_6、人GM_CSFcDNA 5′末端序列进行沉默突变 ,改善其与 16srRNA 3′端 +146 9——— +1482序列的匹配性后 ,目的蛋白的表达量均呈不同程度地提高。结论 :提高起始密码下游序列与 16srRNA 3′端 +146 9——— +1482局部序列间的匹配性 ,可增强目的基因的表达效率。     

GNAS gene mutations affecting XLαs and bone health: A long neglected relationship

The GNAS locus is an imprinted site. The α-subunit of the stimulatory G protein (Gsα) and extralarge variant (XLαs) are the two important products of the GNAS locus. The abnormal expression of Gsα is associated with pseudohypoparathyroidism (PHP) and related disorders, including Albright hereditary osteodystrophy (AHO), pseudopseudohypoparathyroidism (PPHP), and progressive osseous heteroplasia (POH). XLαs protein can mimic the catalytic intracellular synthesis of cyclic adenosine monophosphate (cAMP) by Gsα in response to parathyroid hormone (PTH) stimulation, which may be involved in the pathogenesis of PPHP and POH in patients with paternal GNAS defects. A paternally inherited nonsense variant in the first exon of XLαs in an adult patient may be associated with fractures and osteopetrosis. The relationship between the XLαs product of the GNAS locus and bone remodeling may have been overlooked. Here, we summarize the phenotypes of genetic mouse models and clinical cases of XLαs variations and suggest that the abnormal paternal expression of XLαs may be associated with the development of POH and affect osteoblast and osteoclast differentiation.     

电化教育在医学生素质教育中的作用

电化教育随着时代的变迁和社会的发展以及医学科学特点,在医学教育中的地位不断加强,尤其是在医学素质教育中,发挥着重大作用。     

Messenger-rnas for activin and activin receptors are expressed in fetal bovine heart endothelial-cells

Inhibin and activin, members of transforming growth factor beta (TGF beta) superfamily, have been localized immunohistochemically in fetal bovine heart endothelial cells (FBHE), suggesting that these cells produce inhibin/activin proteins. In addition, the mRNAs coding for alpha-, and beta A-subunits of inhibin/activin, and activin receptor II were expressed in these cells by in situ hybridization technique. It is concluded that inhibin/activin and activin receptor are expressed in FBHE and activin may have autocrine functions in these cells.     

高压下滴流床反应器动持液量的测定

在常压－２．０ＭＰａ的系统压力下测定了滴流床中气－液两相并流下流动的动持液量,了气－液流率,液相粘度,填料大小,压力以及床层高度对动持液量的影响。实验结果表明增中液体流率动持流量增加,气体流率增加时,结果相反粘度的增加对动持液量的影响不大,动持液量随填料空隙率的增大而变小。     

微波治疗耳鼻喉科疾病疗效观察

探索耳鼻喉慢性炎症的简便有效疗法。方法：对１０２例病人表麻下用微波辐射探头定量向病 变组织输入电磁波。结果：随访观察半年以上,治愈率达８８．２４％,有效率达１００％。结论：此方法操作简便,疗 效好,病人痛苦小,值得临床推广。     

咬合板治疗颞下颌关节紊乱病的时机与疗效

目的：通过对颞下颌关节紊乱病（ＴＭＤ） 的临床表现及咬合板治疗的疗效进行分析,探讨ＴＭＤ 的最佳治疗时机。方法：对１５６ 例经咬合板治疗的ＴＭＤ患者就诊时间及治疗２ 个月后治疗效果做分类统计分析。结果：治疗２ 个月后疼痛、弹响及张口受限的总治愈率分别为８１．４％ 、４９．０％ 和８１．５％ 。其中于发病４ 周内就诊的患者治愈率分别为９３．２％ 、７７．３％ 和９３．２％ ,于４ 周后就诊的患者治愈率分别为７３．９％ 、４０．８ ％ 和３０．０ ％ ,两组差异显著（ 弹响及张口受限, Ｐ＜ ０．０１,疼痛Ｐ＜０．０５）。结论：ＴＭＤ在发病４ 周内进行咬合板治疗效果满意。     

聚合酶链反应检测细菌16S rRNA基因

根据细菌１６ＳｒＲＮＡ基因的高度保守性,设计合成所有细菌、革兰氏阳性细菌及革兰氏阴性细菌的共同引物,采用聚合酶链反应检测已知细菌１３株,三对引物分别扩增的阳性率为１００％,倍比稀释法能检出细菌的最低浓度为４ＣＦＵ·ｍｌ－１,同时检测临床样本４０份,阳性率为６７５％（２７／４０）,同期细菌培养阳性率为４５％（１８／４０）,二者比较差异有显著性（Ｐ＜０．０５）。结果提示聚合酶链反应检测细菌１６ＳｒＲＮＡ基因具有高度的特异性和敏感性。     

Development and clinical application of dental spot weld & heat-treat tri-uses device]

A spot weld & heating treatment tri-uses device based on modern mechanical-electric technique, was developed for dental spot weld, stainless steel orthodontic wire heating-reversion and Ni-Ti orthodontic wire heating-overload metamorphism. The device will be very helpful instrument in orthodontic clinic. The paper not only described the operating methods of the device, but also discussed the Performance-improved principles of stainless steel orthodontic wire and the principles of heating overload metamorphism of Ni-Ti orthodontic wire.