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101.
We report a 24-year-old male with an unusual combination of two inherited neuromuscular disorders – Charcot-Marie-Tooth (CMT) disease type 1A and Duchenne muscular dystrophy (DMD). A phenotypic presentation of this patient included features of both these disorders. Nerve conduction studies revealed demyelinating peripheral neuropathy. Electromyography showed a profound myogenic pattern. The serum creatine kinase level was highly elevated. Muscle biopsy revealed a dystrophic picture with deficient dystrophin immunostaining. CMT1A duplication on chromosome 17p11.2 was found. The frame-shift mutation c.3609–3612delTAAAinsCTT (p.K1204LfsX11) was detected in the dystrophin gene by analysing mRNA isolated from the muscle tissue. The patient inherited both these mutations from his mother. The combination of CMT1A and DMD has not been reported as yet.  相似文献   
102.
目的 构建含人端粒酶反转录酶(hTERT)核心启动子调控的人钠/碘同向转运体(hNIS)基因重组腺病毒,并靶向转染至肺癌A549细胞中特异性表达.探讨hTERT启动子调控的hNIS基因介导放射性碘治疗肿瘤的可能性.方法 应用AdEasy系统构建重组腺病毒Ad-hTERT-hNIS,同时构建巨细胞病毒(CMV)启动子调控的hNIS重组腺病毒Ad-CMV.hNIS作为阳性对照,不含hNIS的重组腺病毒Ad-CMV作为阴性对照.应用反转录.聚合酶链反应(RT-PCR)方法验证hTERT在转染肿瘤细胞中的转录活性,摄碘实验检测表达的hNIS蛋白功能,细胞克隆形成实验评价131I对转染肿瘤细胞的毒性作用.结果 成功构建重组腺病毒Ad-hTERT-hNIS、Ad-CMV-hNIS及Ad-CMV,并经PCR验证正确.RT-PCR证实hNIS cDNA能从Ad-hTERT-hNIS转染的细胞中扩增出来.Ad-hTERT-hNIS和Ad-CMV-hNIS转染的肺癌A549细胞摄碘能力比阴性对照组Ad-CMV转染的细胞分别提高了23和31倍,且摄碘能力可以被NaClO4抑制.Ad-hTERT-hNIS和Ad-CMV-hNIS转染的肺癌A549细胞均可被131I杀死,2组细胞成活率分别为(31.2±1.45)%和(23.6±4.08)%,而阴性对照组和未转染病毒组分别为(89.0 ±2.99)%和(91.2 ±4.63)%.结论 hTERT启动子调控的hNIS重组腺病毒转染肿瘤细胞后,应用131I治疗有望成为一种新的基因靶向治疗手段.  相似文献   
103.
Administration of cholinotoxin etylcholine aziridinium (AF64A) into the brain selectively induces nonrever-sible cholinergic deficit. Wistar rats were injected intracerebroventricularly bilaterally with AF64A at doses of 1–3 nmol/ventricle. 28 days later the number of neurons survived was counted in dorsolateral, intermediate and medial groups of cells of the medial septum. AF64A induced a decrease in neuronal density and expression of cholineacetyl transferase at all doses used as well as in all regions studied. Brain sections were also stained for NADPH-diaphorase representing neuronal NO-synthase. Effects of AF64A on NADPH-diaphorase expression depended on the region studied. The number of NADPH-diaphorase-positive cells increased in the medial cellular group where more cholineacetly transferase-positive cells survived. In contrast, decrease in NADPH-diaphorase expression in the dorsolateral group of cells coincided with low level of cholineacetyltransferase-po-sitive neurons. The data presented suggest that in the AF64A-dependent model of neurodegeneration NO may play a neuroprotective function.  相似文献   
104.
目的 对核工业地质勘查计量站的 8个圆柱型环境电离辐射体源和两个本底模型上方不同高度处的空气吸收剂量率进行较为准确的定值。方法 采用蒙特卡罗软件MCNP ,对上述环境电离辐射体源和本底模型上方的空气吸收剂量率进行了模拟计算 ,采用 1台高气压电离室剂量率仪对各环境电离辐射体源和本底模型上方不同高度处的空气吸收剂量率进行了实测 ,模拟计算结果与实测结果以及其他工作者过去所作的剂量率测量和计算结果进行了比较。结果 MC模拟计算值与其他工作者得到的空气吸收剂量率理论值吻合较好 ,最大偏差小于 10 % ,一般偏差小于±5 %。结论 只要各种输入参数准确 ,采用MC模拟计算 ,可以得到辐射体源和本底模型上方不同高度处较准确 (3%不确定度 )的空气吸收剂量率模拟计算值。  相似文献   
105.
 目的探讨环孢素A(cyclosporine A,CsA)是否逆转野百合碱(monocrotaline,MCT)诱导的右心室重构及其作用机制的初步探讨。方法雄性SD大鼠随机分正常对照组,MCT模型组,CsA低、高剂量组(0.33和1mg·kg-1)。MCT造模后14~21d给CsA(ig,bid)。造模22d右心导管术检测右室收缩压(RVSP);称右室自由壁(RV)及左心室加室间隔(LV+SEP)重,计算右心肥大指数(RVHI=RV/LV+SEP);光镜及电镜观察右室结构变化;免疫组化检查右室心肌细胞PCNA的表达。结果CsA逆转MCT所引起RVSP、RVHI的升高(P<0.05或P<0.01)、右室心肌细胞肥大、线粒体肿胀变性及PCNA抗原的过表达。高剂量CsA作用更明显。结论CsA(1mg·kg-1 ig,bid)能明显逆转MCT诱导的右室重构,其机制可能与降低右室后负荷及抑制右室心肌细胞肥大有关。  相似文献   
106.
Flavocoxid (Limbrel), a proprietary mixture of flavonoid molecules (baicalin and catechin), was tested against a traditional nonsteroidal anti-inflammatory drug, naproxen, for the management of the signs and symptoms of moderate osteoarthritis (OA) in humans. Discomfort and global disease activity were used as the primary end points, and safety assessments were also taken for both treatments as a secondary endpoint. In this double-blind study, 103 subjects were randomly assigned to receive either flavocoxid [500 mg twice daily (BID)] or naproxen (500 mg BID) in a 1-month onset of action trial. Outcome measures included the short Western Ontario and McMaster University Osteoarthritis Index, subject Visual Analogue Scale for discomfort and global response, and investigator Visual Analogue Scale for global response and fecal occult blood. Both flavocoxid and naproxen showed significant reduction in the signs and symptoms of knee OA (P ≤ .001). There were no statistically detectable differences between the flavocoxid and naproxen groups with respect to any of the outcome variables. Similarly, there were no statistically detectable differences between the groups with respect to any adverse event, although there was a trend toward a higher incidence of edema and nonspecific musculoskeletal discomfort in the naproxen group. In this short-term pilot study, flavocoxid was as effective as naproxen in controlling the signs and symptoms of OA of the knee and would present a safe and effective option for those individuals on traditional nonsteroidal anti-inflammatory drugs or cyclooxygenase-2 inhibitors. A low incidence of adverse events was reported for both groups.  相似文献   
107.
1994~2002年广西甲型副伤寒和伤寒流行情况分析   总被引:12,自引:3,他引:9  
目的 了解1994~2002年接种伤寒Vi疫苗后的7年间伤寒和副伤寒流行变化,评价Vi疫苗对控制伤寒流行的效果并分析甲型副伤寒的特征及影响其爆发流行的因素。方法对自治区疾病控制中心实验室记录、伤寒副伤寒爆发调查报告、监测系统资料、全区伤寒流行地区伤寒Vi疫苗供应情况进行统计分析。结果 经过血培养证实甲型副伤寒病例为1200例、伤寒为285例;甲型副伤寒与伤寒的流行病学、临床特征十分相似;饮用污染水是引起甲型副伤寒爆发的主要原因;从1999年起,甲型副伤寒杆菌开始超过伤寒菌为优势流行菌株。结论 在广泛使用伤寒Vi疫苗后,伤寒基本得到控制,但因为引起副伤寒发病的危险因素依然存在,甲型副伤寒已取代寒,成为广西农村地区的最重要的传染病之一。为控制甲型副伤寒的流行,在安全饮用水供应状况得到全面改善之前,应尽快研制出副伤寒疫苗。  相似文献   
108.
We report here the antiproteolytic and antihemorrhagic properties of triterpenoid saponin inhibitors, named macrolobin-A and B, from Pentaclethra macroloba, against Bothrops snake venoms. The inhibitors were able to neutralize the hemorrhagic, fibrin(ogen)olytic, and proteolytic activities of class P-I and P-III metalloproteases isolated from B. neuwiedi and B. jararacussu venoms. Clotting and fibrinogenolytic activities induced by snake venoms and isolated thrombin-like enzymes were partially inhibited. Furthermore, the potential use of these inhibitors to complement antivenom therapy as an alternative treatment and/or used as molecular models for development of new therapeutical agents in the treatment of snake bite envenomations needs to be evaluated in future studies.  相似文献   
109.
The distribution of methionine-enkephalin-Arg6-Gly7-Leu8, a unique peptide derived from proenkephalin A in the rat brainstem, was studied immunocytochemically by using a highly specific antiserum to this octapeptide sequence. Immunoreactive perikarya with various shapes and sizes were detected in many regions of the rat brainstem. Dense accumulation of immunoreactive perikarya and fibers was seen in the nuclei associated with special sensory and visceral functions, such as the interpeduncular nucleus, the parabrachial nucleus, the nucleus of the solitary tract, and the nucleus of the spinal tract of the trigeminal nerve. Clusters of methionine-enkephalin-Arg6-Gly7-Leu8-like immunoreactive perikarya and fibers were observed in certain areas considered to play a role in nociception and analgesia, such as the central gray of the midbrain central gray and the raphe magnus nucleus. Some methionine-enkephalin-Arg6-Gly7-Leu8-like immunoreactive perikarya were distributed in the lateral reticular nucleus, the nucleus of the solitary tract, and the raphe magnus nucleus, where monoaminergic neurons were also detected. In addition to the previously reported enkephalinergic cells, we found many methionine-enkephalin-Arg6-Gly7-Leu8 containing neurons; the rostral and caudal linear nucleus of raphe, the median raphe nucleus, entire length of the raphe magnus nucleus, the medial longitudinal fasciculus, the cuneate nucleus, the external cuneate nucleus, the gracile nucleus, and the area postrema. The wide distribution of this octapeptide-like immunoreactivity reflected neurons expressing the preproenkephalin A gene distributed more widely than previously reported and that innervated many regions.  相似文献   
110.
Despite the use of gold complexes in modern medicine for over 100 years and the use of gold complexes in the management of rheumatoid disease for more than 60 years, the definitive mechanisms of action for efficacy and for toxicity have not been established. Gold is a group 1b metal in the periodic table with several oxidation states but it is only Au(I) which is active in the biological milieu. Gold sodium thiomalate is not only a polymeric structure, but also has the chiral ligand, thiomalic acid. Gold sodium thiomalate thus can exist in several different physical states which may have different biological activity. In addition the pharmacokinetic profile of gold complexes has been of little value in the understanding of either the mechanism of action, efficacy or toxicity for both the injectable and the oral gold complexes. Many authors have misinterpreted research data on the activities of gold complexes because they compared gold complexes of different structures, and gold complexes which exist at different pH. Experimental work in our laboratory has identified that gold sodium thiomalate is a mixture and can exist as either a yellow or a colourless solution. These have some similar but several different biological activities. Many factors contribute to the lack of understanding of the action of gold complexes. Some of these factors are related to the wide variation in physical structure and biological activities exhibited by these compounds.  相似文献   
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