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51.
The measurement of amniotic fluid (AF) acetylcholinesterase isoenzyme (AChEI) is a relatively new method for early diagnosis of open neural tube defects (NTDs). As quantitative methods are of unproven reliability at present, the authors used a high resolving power qualitative method-vertical slab polyaerylamide gel electrophoresis. The benefits of this technique are: simplicity of operation, accuracy, unsophisticated equipment, and easily available reagents. Combined results of 9 NTDs studies revealed that samples from early pregnancy gave more accurate results than those from late pregnancy.  相似文献   
52.
Although several studies have demonstrated the efficacy of subcutaneous immunotherapy in allergic asthma, few have shown the same benefit using sublingual immunotherapy (SLIT) in asthmatic patients. This study was conducted to assess the efficacy of house dust mite (HDM) SLIT in addition to allergen avoidance and standard pharmacologic treatment. A double-blind, placebo-controlled trial was performed in 111 children (aged 5-15 yr) with HDM-induced mild-to-moderate asthma. After a 4-week baseline phase, patients were randomly assigned to receive SLIT with tablets of HDM extract (n = 55) or placebo (n = 56) for 18 months. Pharmacologic treatment was adjusted every 3 months following a step-down approach. Asthma symptom scores, reduction in use of inhaled corticosteroids and inhaled beta(2)-agonists, rhinitis symptoms, lung function tests, skin sensitivity to HDM, dust mite-specific immunoglobulin (Ig) E and IgG(4), and quality of life (QoL) were assessed during the study. After 18 months of treatment, diurnal and nocturnal asthma symptoms scores did not show significant differences between SLIT and placebo groups. Inhaled corticosteroids and inhaled beta(2)-agonists use was reduced in both groups without significant differences between groups. There were no significant differences in lung function (forced expiratory volume in 1 s and peak flow rate variations) between groups. Rhinitis symptom score decreased in both groups, with no difference between the two groups. The severity dimension of QoL was significantly improved in the SLIT group (age 6-12 yr). SLIT induced a significant reduction of skin sensitivity to HDM (p < 0.01) and a significant increase in HDM-specific IgE and IgG(4) antibodies (p < 0.001) in the SLIT group compared with the placebo group. SLIT was well tolerated with mild/moderate local adverse events. No severe systemic reactions were reported. This study indicates that, when mild-moderate asthmatic children are optimally controlled by pharmacologic treatment and HDM avoidance, SLIT does not provide additional benefit, despite a significant reduction in allergic response to HDM. Under such conditions, only a complete, but ethically unfeasible, discontinuation of inhaled corticosteroid would have demonstrated a possible benefit of SLIT.  相似文献   
53.
本文报告胰岛细胞脑内移植治疗I型糖尿病共3例,分别经过3个月、4个月、6个月的临床观察,其临床症状明显改善或消失,空腹血糖由移植前平均12.38mmol/L下降至7.77mmol/L;3例患者普通胰岛素用量平均每日62.3~u,移植后第21~30天均完全停用胰岛素,其中1例已持续撤离胰岛素治疗达5个月。观察结果提示:胰岛移植物在患者的脑内成活,并具有良好的内分泌功能。  相似文献   
54.
There are more than 40 H(1)-antihistamines available worldwide. Most of these medications have never been optimally studied in prospective, randomized, double-masked, placebo-controlled trials in children. The aim was to perform a long-term study of levocetirizine safety in young atopic children. In the randomized, double-masked Early Prevention of Asthma in Atopic Children Study, 510 atopic children who were age 12-24 months at entry received either levocetirizine 0.125 mg/kg or placebo twice daily for 18 months. Safety was assessed by: reporting of adverse events, numbers of children discontinuing the study because of adverse events, height and body mass measurements, assessment of developmental milestones, and hematology and biochemistry tests. The population evaluated for safety consisted of 255 children given levocetirizine and 255 children given placebo. The treatment groups were similar demographically, and with regard to number of children with: one or more adverse events (levocetirizine, 96.9%; placebo, 95.7%); serious adverse events (levocetirizine, 12.2%; placebo, 14.5%); medication-attributed adverse events (levocetirizine, 5.1%; placebo, 6.3%); and adverse events that led to permanent discontinuation of study medication (levocetirizine, 2.0%; placebo, 1.2%). The most frequent adverse events related to: upper respiratory tract infections, transient gastroenteritis symptoms, or exacerbations of allergic diseases. There were no significant differences between the treatment groups in height, mass, attainment of developmental milestones, and hematology and biochemistry tests. The long-term safety of levocetirizine has been confirmed in young atopic children.  相似文献   
55.
Background: Volatile anesthetics are commonly used for general anesthesia. However, these can induce profound cardiovascular alterations. Xenon is a noble gas with potent anesthetic and analgesic properties. However, it is uncertain whether xenon alters myocardial function. The aim of this study was therefore to investigate left ventricular function during anesthesia with xenon compared with isoflurane.

Methods: The authors performed a randomized multicenter trial to compare xenon with isoflurane with respect to cardiovascular stability and adverse effects in patients without cardiac diseases scheduled for elective surgery. Two hundred fifty-nine patients were enrolled in this trial, of which 252 completed the study according to the protocol. Patients were anesthetized with xenon or isoflurane, respectively. Before administration of the study drugs and at four time points, the effects of both anesthetics on left ventricular function were investigated using transesophageal echocardiography.

Results: Global hemodynamic parameters were significantly altered using isoflurane (P < 0.05 vs. baseline), whereas xenon only decreased heart rate (P < 0.05 vs. baseline). In contrast to xenon, left ventricular end-systolic wall stress decreased significantly in the isoflurane group (P < 0.05 vs. baseline). Velocity of circumferential fiber shortening was decreased significantly in the xenon group but showed a more pronounced reduction during isoflurane administration (P < 0.05 vs. baseline). The contractile index (difference between expected and actually measured velocity of circumferential fiber shortening) as an independent parameter for left ventricular function was significantly decreased after isoflurane (P < 0.0001) but unchanged using xenon.  相似文献   

56.
57.
特发性颈椎后凸畸形的手术治疗   总被引:3,自引:1,他引:2  
目的 :明确颈椎前路手术治疗特发性颈椎后凸畸形的可行性和局限性。方法 :本文对 14例颈椎特发性后凸畸形患者采取手术方法进行治疗 ,所有患者均采用颈椎前路椎间盘切除减压 ,椎间隙植骨和前路钢板内固定。结果 :手术后患者临床体征明显改善 ,颈椎后凸畸形由手术前平均 -15 6°矫正为手术后平均 -6 4° ,矫正效果明显 ;手术后患者的短期随访表明颈椎矫正度数在随访中没有丢失。结论 :前路手术 ,延长颈椎前柱能够矫正颈椎的后凸畸形 ,改善临床症状和体征  相似文献   
58.
根据近几年来发表的与铁稳态有关的生物分子的研究文献 ,将这些生物分子根据其与铁的吸收、转运、储存以及对铁稳态的监控调节等方面的关系 ,对这些生物分子进行了分类。特别是对细胞膜载体、运铁蛋白受体、铁调蛋白及铁反应元件等作了较为详细地论述  相似文献   
59.
应用和推广烧伤皮肤再生医疗技术的体会(二)   总被引:1,自引:1,他引:0  
目的:通过临床实践总结、分析、认识干细胞与再生医学理论在烧伤创疡中的作用与效果;方法:应用MEBT/MEBO观察烧伤创疡创面的再生修复变化。结果:MEBT/MEBO治疗77种创疡疾病冶愈率达92%以上,有效率达100%。结论:MEBT/MEN)治疗慢性体表性溃疡及皮肤病性皮肤损伤、感染性溃疡效果满意。  相似文献   
60.
目的探讨如何通过放大内镜观察到的大肠粘膜腺管开口类型发现早期大肠癌及癌前病变。方法2001年8月~2002年2月结肠镜检查139例大肠病变,采用内镜下粘膜染色技术,结合放大内镜、实体显微镜观察腺管开口分型(pit分型)并与病理诊断对照,pit分型采用工藤分型。结果139例患者中发现大肠息肉124例,进展期癌9例,侧向发育型肿瘤(LST)型病变5例,ⅡC病变1例。LST直径10~50 mm,其中ⅢL型1个,Ⅳ型4个。本组放大内镜与病理、实体镜诊断符合率较高。结论大肠腺管开口对于判断肿瘤性、非肿瘤性病变以及早期大肠癌具有重要意义,如发现有Ⅴ型腺管开口时则高度提示早期癌的可能。  相似文献   
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