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41.
Huey-Juan Lin Poh-Shiow Yeh Tsung-Chia Tsai Tain-Junn Cheng Dershin Ke Kao-Chang Lin Jih-Gong Ho Chia-Yu Chang 《Journal of clinical neuroscience》2007,14(1):17-21
Using a prospective hospital-based registry, 146 patients with transient ischaemic attack (TIA) were compared with 376 patients with minor first-ever ischaemic stroke with respect to the 3-month risk of subsequent vascular events, in order to clarify the distinctions between the disease entities. All patients were enrolled within 48 h of onset. The risk factor distribution for the two groups was comparable, except that the TIA patients had more previous TIAs. Large artery atherosclerosis (34%) and small vessel occlusion (32%) were the main aetiologies in the TIA group, whereas small vessel occlusion (49%) was the major cause in the stroke group. The 3-month risk of combined endpoints of stroke, myocardial infarction, and vascular death for TIA patients was higher than that for the minor stroke group (15.1% vs. 3.2%; hazard ratio 4.6, 95% confidence interval 2.3-9.3 in multivariate analysis). Large artery atherosclerosis and male sex were the other significant predictors. TIA may demand more urgent management than minor stroke. The fact that aetiology is a predictor, highlights the need for rapid diagnostic tests to establish pathogenesis. 相似文献
42.
Recapitulation of fast skeletal muscle development in zebrafish by transgenic expression of GFP under the mylz2 promoter. 总被引:1,自引:0,他引:1
Bensheng Ju Shang Wei Chong Jiangyan He Xukun Wang Yanfei Xu Haiyan Wan Yan Tong Tie Yan Vladimir Korzh Zhiyuan Gong 《Developmental dynamics》2003,227(1):14-26
A 1,934-bp muscle-specific promoter from the zebrafish mylz2 gene was isolated and characterized by transgenic analysis. By using a series of 5' promoter deletions linked to the green fluorescent protein (gfp) reporter gene, transient transgenic analysis indicated that the strength of promoter activity appeared to correlate to the number of muscle cis-elements in the promoter and that a minimal -77-bp region was sufficient for a relatively strong promoter activity in muscle cells. Stable transgenic lines were obtained from several mylz2-gfp constructs. GFP expression in the 1,934-bp promoter transgenic lines mimicked well the expression pattern of endogenous mylz2 mRNA in both somitic muscle and nonsomitic muscles, including fin, eye, jaw, and gill muscles. An identical pattern of GFP expression, although at a much lower level, was observed from a transgenic line with a shorter 871-bp promoter. Our observation indicates that there is no distinct cis-element for activation of mylz2 in different skeletal muscles. Furthermore, RNA encoding a dominant negative form of cAMP-dependent protein kinase A was injected into mylz2-gfp transgenic embryos and GFP expression was significantly reduced due to an expanded slow muscle development at the expense of GFP-expressing fast muscle. The mylz2-gfp transgene was also transferred into two zebrafish mutants, spadetail and chordino, and several novel phenotypes in muscle development in these mutants were discovered. 相似文献
43.
显微锁孔手术治疗脑干及其周围病变 总被引:4,自引:0,他引:4
目的 将显微锁孔手术应用于脑干及其周围病变的外科治疗,探求以最小的创伤来取得最佳的手术疗效。方法 采用颞下锁孔人路、乳突后锁孔人路、枕下正中锁孔人路,以20mm左右直径的骨窗进行脑干及其周围病变的显微手术治疗。结果 本组16例例病人术后3d内均行MRI或DSA检查,肿瘤或动静脉畸形全切除11例,次全切除3例,部分切除1例,1例小脑后下动脉瘤成功夹闭。术中输血3例。并发脑脊液耳漏1例,硬膜下积液1例,1例术后持续昏迷40d苏醒,无死亡及感染病例。结论 锁孔人路微创技术处理脑干及其周围病变,因其手术创伤小,疗效佳,费用节省,值得临床推广应用。 相似文献
44.
Ming-I. Hsu Paul Kolm John Leete Ke Wen Dong Suheil Muasher Sergio Oehninger 《Journal of assisted reproduction and genetics》1998,15(8):496-503
Purpose:
Our purpose was to examine implantation of singleton pregnancies achieved following various assisted reproductive technologies (ARTs) through the appearance and rising titers of serum human chorionic gonadotropin (hCG) levels.
Methods:
A total of 114 singleton pregnancies resulting from in vitro fertilization and intrauterine insemination was analyzed. Patients were divided into five groups according to the type of ovarian stimulation protocol [gonadotropin stimulation with/without the use of gonadotropin-releasing hormone agonist (GnRHa), long protocol, or flare-up technique] and to the day of embryo transfer (day 2 or day 3 after oocyte retrieval). Serial serum hCG levels were measured between 10 and 25 days after fertilization and log-transformed. Linear regression analyses were performed and extrapolated to hCG = 10 mIU/ml (hCG
10
), which was used as an estimate of detectable implantation. The slopes of the regression lines were used to estimate the rising speed of hCG.
Results:
There were no significant differences in the days of hCG in maternal serum to reach 10 mIU/ml (implantation) or in the slopes of the regression lines for all five studied groups.
Conclusions:
The appearance of hCG in maternal serum was used to assess the time of clinically detectable implantation. Furthermore, because hCG production is a marker of trophoblastic activity, its serum doubling time was used as an indicator of embryo quality. Results showed that in various ART protocols with and without GnRHa, there were no significant differences in implantation time or embryo quality. Embryo development in early pregnancy follows a preprogrammed-timing schedule and depends mainly on the embryonic age of the health, successfully implanted conceptus. 相似文献
45.
用机械分离法从豚鼠前庭感觉上皮中分离出不同种类的前庭感觉毛细胞(VHC)。VHC主要可分为Ⅰ型和Ⅱ型细胞。两种细胞形态虽有所差异,但一般均有四形或瓶形胞体,胞核位于细胞基部,胞颈和纤毛变化较大。细胞的活性可通过1%中性红染色鉴定,发现在室温下,1h内大约90%以上的分离VHC可维持其正常形态和活性。并参照对外毛细胞形态的研究提出活性VHC的鉴别标准。此项工作为进一步研究VHC的感觉机制和某些疾病的发生机理打下了基础。 相似文献
46.
肝腺瘤的影像学诊断 总被引:5,自引:1,他引:4
目的探讨影像学(US、CT、MRI及DSA)诊断肝腺瘤的价值。方法回顾性分析经手术、病理证实的11例肝腺瘤的影像学表现,其中11例行US和CT检查(有1例行CT灌注成像,CTP),5例行MRI扫描,4例行DSA检查,并与手术病理所见对照。结果11例肝腺瘤均为单发肿块,无肝硬化背景,直径2.0~10.0cm。影像学表现:US检查,10例呈稍低或不均匀稍强回声,边界清晰,6例见低回声晕,彩色多普勒显示肿块内有较丰富的血流;CT检查,10例为稍低或等密度,8/10例动脉期全瘤明显强化,门脉期轻度强化,延迟期呈等密度,1例平扫和延迟期呈等密度,动脉期中度强化,门脉期轻度强化,误诊为血管瘤。1/11例CT灌注成像(CTP)检查,肝动脉灌注量(HAP)=1.08ml/(min.ml),门静脉灌注量(PVP)=0.19ml/(min.ml),肝动脉灌注指数(HPI)=0.85,各参数值与肝癌均有明显不同;MRI检查,5例肝腺瘤均能显示完整包膜,T1WI上2例稍高于肝脏信号,1例呈等信号,2例为稍低信号,T2WI上5例均表现为以稍高信号为主的混杂信号,脂肪抑制像(STIR)1例呈略低信号,4例信号与T2WI相似,行增强扫描的4例病灶动脉期显著强化,门脉期强化减退,平衡期呈等信号。DSA检查,3/4例病灶见粗细不均的异常血管影,实质期可见肿瘤染色表现。结论肝腺瘤的US和DSA表现均缺乏特异性,CT、MRI则具有一定的特点。CTP对肝腺瘤可能具有诊断和鉴别诊断价值。 相似文献
47.
目的观察无抽搐电痉挛(Modified Electrocnvulsive therapy,MECT)治疗精神分裂症的疗效及给予次数的关系。方法将60例诊断为精神分裂症的住院患者按治疗次数随机分为两组,进行MECT的临床资料总结分析。结果治疗次数≥6次组,显效率为83.3%,次数〈6次组显效率为76.7%,两者显效率无显著性差异(P〉0.05),每组治疗前后BPRS评分有显著差异,但两组间比较无显著差异(P〉0.05),未发现严重不良反应。结论MECF安全性高,有一定疗效,与治疗次数关系不大。 相似文献
48.
巴金森氏病病人的年龄、起病年龄、病程、运动障碍的严重程度与其智力损害的关系至今仍存有争议。为此用定量的临床评定方法、标准化的韦氏成人智力测验对31名连续收选的特发性巴金森氏病进行了研究。结果发现缓动的严重程度与智力损害明显相关,而震颤严重程度与智力损害呈反相关。病人的年龄、起病年龄、病程及强直的程度与智力损害无明显相关。这些结果提示引起缓动的皮层下脑损害同样可能引起智力损害,而有明显震颤的巴金森氏病可能属于该病的早期或属于智力损害较轻的一种巴金森氏病亚型。 相似文献
49.
在10只麻醉开胸犬的左前降支冠状动脉(LAD)恒流灌注,持续监测灌注压,并于冠脉内注入2.5mg心得宁以阻断心脏的β_1-肾上腺素能受体,观察去甲肾上腺素(NE,α-肾上腺素能刺激)对LAD内给予腺苷所致冠状血管舒张的限制作用。随着LAD内注入的腺苷量增加,冠状动脉阻力(R)咸剂量依赖性降低,分别为对照值的8.7%(2μg/min),20.6%(10μg/min)和28%(50μg/min)。而于LAD内再给予相同齐0量(6μg)的NE,则使不同剂量扩张的冠脉收缩,R成阶梯状增加,分别为对照值的17.4%(腺苷2μg/ml),23.2%(腺苷10μg/min)和34.1%(腺苷50μg/min),表现为隙苷引起的冠状血管扩张愈大,NE能刺激引起的缩血管作用愈强。这表明α-肾上腺素能缩血管作用可限制腺苷引起的冠状血管舒张,因而有助于保持冠状血管张力及其储备力。 相似文献
50.