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81.
We assessed the efficacy and adverse effects of ivermectin for the treatment of chronic strongyloidiasis. Fifty patients were treated with a single dose of ivermectin at approximately 200 μg/kg, and the dose was repeated 2 weeks later. The eradication rate was 96% (48 of 50 patients) at 2 weeks after the first dose and 98% at 2 weeks after the second dose (49 of 50 patients). In the latter cases, no recurrence was noted at the end of the 4-month post-treatment follow-up period. The gastrointestinal symptoms observed most frequently before the treatment were borborygmus, constipation, and diarrhea. These symptoms improved in the majority of patients after the treatment. Side effects, including nausea and vomiting, occurred in 1 patient (2%), but these were mild and transient. Although abnormal values in laboratory tests were observed in 4 patients (8%), they were mild, and no particular clinical care was required. Thus, ivermectin showed an excellent antihelminthic effect, with little toxicity. Our results indicate that a regimen of two single doses of 200 μg/kg ivermectin, given 2 weeks apart, is clinically suitable for the treatment of chronic strongyloidiasis. Received: April 25, 2001 / Accepted: November 16, 2001  相似文献   
82.
In the developing spinal cord of the frog, Xenopus laevis, a population of interneurons assumes a pattern that represents a previously undescribed level of organization. Glyoxylic acid treatment and immunocytochemistry show that the neurons contain catecholamines and their synthetic enzyme, tyrosine hydroxylase. Cells are located within the ependymal layer of the floor plate region of the larval spinal cord. The cells have several processes including a long one that projects toward the brain without fasciculating with other labeled processes. In addition, the cytoplasm of the catecholaminergic cells extends into the central canal, showing that they are a population of cerebrospinal fluid-contacting neurons. The spatial domain of catecholaminergic neurons starts abruptly at the boundary between the hindbrain and spinal cord and continues to the tip of the tail. The neurons occupy two longitudinal columns within the sheet of floor plate cells, which includes cells that do not exhibit the catecholaminergic phenotype. Unlabeled cells are intercalated between catecholaminergic cells in each column, giving the labeled cells the appearance of being spaced along the length of the spinal cord. This general arrangement is evident at the time of hatching. Spatial analysis showed that the position of cells along a column is not random. The nonrandom behavior is due to cells being excluded from the area immediately surrounding other catecholaminergic cells. Further analysis showed that the cellular pattern lacks segmental or other periodic repeats. Ultimately, the location of a cell within a column depends upon the position of its closest catecholaminergic neighbor. © 1993 Wiley-Liss, Inc.  相似文献   
83.
目的:针对目前小儿颅骨缺损的多种治疗观念及课题组前期研究提出的“滑行理论”,利用幼龄SD大鼠模型探究颅骨缺损及钛网修补后对其颅骨生长和智力发育的影响。方法:将3周幼龄SD大鼠随机分成假手术对照组(SOC)、颅骨缺损组(SD)和钛网修补组(TMR),术前排除组间差异,术后同环境下饲养至性成熟进行旷场实验和Morris水迷宫实验后处死,测量体质量、颅骨径线、颅骨厚度、缺损内径和脑容积等指标。结果:术前体质量及颅骨径线显示三组间差异无统计学意义(P>0.05),具有可比性;性成熟时体质量、颅骨径线、脑容积三组间均无差异(P>0.05),仅SOC组平均颅骨厚度较大(P<0.05);缺损内径方面SD组与TMR组无差异(P>0.05),且与术前相比均呈狭长形变;旷场实验中总路程、平均速度和静止时间及部分区域数据方面SD组与其他组有差异(P<0.05);Morris水迷宫实验显示第5天逃避潜伏期、首次穿越平台时间和目标象限时间占比等SD组与其他组均有差异(P<0.05)。结论:颅骨缺损未行修补对幼龄大鼠颅骨的正常生长无明显影响,但可能影响其智力发育;钛网修补并不会...  相似文献   
84.
目的 比较改良尿道板重建卷管尿道成形术(又称Koyanagi术)与尿道板纵切卷管尿道成形术(TIP)在儿童尿道下裂中的临床疗效。方法 回顾性分析2018年1月—2021年10月甘肃省妇幼保健院收治的104例尿道下裂患儿的临床资料,其中53例患儿行改良Koyanagi术(研究组),51例患儿行TIP(对照组)。两组患儿术后均随访12个月。比较两组手术时间、术中出血量、术后疼痛及排尿功能、手术成功情况,对比两组术后并发症发生情况。结果 两组手术时间、术中出血量比较,差异均无统计学意义(P >0.05)。两组患儿术后4、12、24和48 h的FLACC评分比较,采用重复测量设计的方差分析,结果 ①不同时间点FLACC评分差异有统计学意义(F =10.871,P =0.000);②研究组与对照组FLACC评分差异无统计学意义(F =1.849,P =0.157);③研究组与对照组FLACC评分变化趋势差异无统计学意义(F =2.516,P =0.085)。两组患儿术后12个月的最大尿流率、平均尿流率、排尿量、尿流时间、手术成功率比较,差异均无统计学意义(P >0.05)。研究组术后总并发症发生率低于对照组(P <0.05)。结论 改良Koyanagi术与TIP治疗儿童尿道下裂疗效相近,均可获得满意效果,但改良Koyanagi术在降低术后并发症方面具有优势。  相似文献   
85.
The distal femoral growth plate has a uniquely convoluted structure comprised of four mammillate processes. Factors contributing to the development of these processes and overall plate geometry were explored using three-dimensional image analysis of the canine distal femoral epiphysis. The growth plate at birth remains relatively flat until ossification of the epiphysis begins at 1 week of age. Epiphyseal ossification proceeds eccentrically, projecting in the medial-lateral and anterior-posterior directions. Growth plate activity indexed by [3H]thymidine labeling and plate thickness revealed regional differences in cell proliferation. This was measured as a decreased labeling index and thinning of the growth plate in areas capped by the ossifying epiphysis. The eccentric ossification pattern and associated variations in growth plate activity result in definition of an "intraphyseal" groove and medial-lateral oriented sulcus. The groove and sulcus bisect the plate into four quadrants, giving rise to a convoluted structure composed of four areas of plate elevations termed mammillary processes (MP). By 5 weeks, the pattern of ossification results in greater development of the MP in the anterior-medial quadrant and in decreasing order, in the posterior-medial, anterior, and posterior-lateral quadrants. By 10 weeks, a uniform rate of cell proliferation was observed coincident with completion of ossification of the epiphysis. The data suggest that localized variations in growth plate proliferation are associated with ossification of the epiphysis.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
86.
目的评估AO肩锁钢板钩治疗重型肩锁关节脱位的手术疗效.方法回顾性分析两年来27例手术病人的手术治疗和疗效.结果手术方法符合生理结构,手术时间平均30分钟,内固定牢靠.根据Murley和Constant[1]评分,优良率94%.结论 AO肩锁钢板钩治疗重型肩锁关节脱位,手术方法简单,疗效可靠,允许病人术后早期功能锻炼.  相似文献   
87.
金属表面TiO2薄膜的溶胶-凝胶法制备及其血液相容性研究   总被引:8,自引:1,他引:8  
通过溶胶 凝胶法制备TiO2 薄膜对 316L不锈钢和NiTi形状记忆合金进行表面改性处理。研究发现 ,经 5 0 0℃处理 1h的薄膜结构致密 ,膜层均匀平滑 ,薄膜主要由锐钛矿相TiO2 构成 ,随热处理温度的提高 ,锐钛矿相逐渐转变为金红石相。电化学腐蚀和动态凝血时间及溶血率测试表明 ,通过溶胶 凝胶法制备TiO2 膜进行表面改性的 316L不锈钢和NiTi合金的抗模拟体液腐蚀性提高 ,动态凝血时间延长 ,溶血率下降 ,说明溶胶 凝胶法制备TiO2 膜可以提高金属植入物的血液相容性  相似文献   
88.
A 72-year-old male painter, who complained of his "lungs burning" for 2 weeks, died suddenly. Autopsy examination revealed severe coronary atherosclerosis with plaque rupture as the cause of death. Examination of the lungs revealed emphysema, interstitial fibrosis, and multinucleated giant cells with intra- and extracellular brown-black, crystalline, polarizable foreign material. Energy-dispersive X-ray microanalysis showed the material to contain titanium, aluminum, silicon, and iron. An increased incidence of respiratory disease has been reported in professional painters. Titanium is widely used as a pigment in the manufacturing of commercial paints. Cases of pneumoconiosis and alveolar proteinosis have been described in painters in which analysis of lung tissue revealed increased levels of titanium. This case is presented as an example of a rarely reported phenomenon, which may have clinical implications for evaluation and management of lung disease in painters.  相似文献   
89.
单钉——沟槽柱翼钢板的生物力学实验研究   总被引:3,自引:0,他引:3  
作者自行研究设计的单钉-沟槽柱翼钢板复位固定治疗腰椎滑脱症。预先采用6具成人尸体的L3-S3骨骼做成椎弓崩裂并滑脱模型,采用临床I型手术方法进行了复位固定,在每片钢板上粘贴6片电阻应变片,进行中心和偏心加载试验,同时进行了弯矩和扭矩试验,在586微机上进行了线性回归分析,求出了线性方程及线性相关系数r,中心和偏心加载达到900N未出现钢板松动,扭矩和弯矩在833N;cm和666.4N.cm以内左右  相似文献   
90.
We targeted the reverse tetracycline controlled transactivator (rtTA) to the Foxa2 locus (Foxa2(ITA)) to generate a system for regulating Cre-recombinase activity within Foxa2 expression domains, including the endoderm, notochord, and floor plate of early mouse embryos. The use of an internal ribosomal entry site to obtain rtTA expression preserves Foxa2 function of the targeted allele. Cre activity with this system reflects the level of endogenous Foxa2 activity and is also tightly controlled by doxycycline. The location of Cre activity within the broader Foxa2 expression domain can be restricted by altering the timing of doxycycline administration. Isolated floor plate expression can be obtained in this manner. This system will provide a useful tool for manipulating gene expression in endoderm, notochord, and floor plate, all of which are tissues with important structural and patterning functions during embryogenesis.  相似文献   
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