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1.
以草酸钛钾溶液为受试物,用无菌操作法在不同浓度试验水样及不含钛的对照水样中加入大肠杆菌稀释液1ml(含菌300个),观察6小时和1-7天的细菌生长情况。结果各受试组与对照组比较,10.0mg/L和1.0mg/L组接触6小时至7天大肠杆菌生长均有明显的抑制作用;0.1mg/L组接触6-24小时显示抑制作用,但第4天开始菌落减少的速度比对照组缓慢。提示钛对大肠杆菌的生长有抑制作用,其作用阈浓度为1.0mg/L,阈下浓度为0,1mg/L。  相似文献   
2.
Summary A group of thirty children with nasal fractures was evaluated retrospectively by means of a questionnaire and hospital records. Age at the time of injury ranged from age 3 to 12 (mean = 8.6) years and mean follow-up period was 9 years. Eight patients reported some degree of nasal obstruction post reduction, but only one patient required submucous resection and two patients underwent septorhinoplasty for appearance. No patients reported class III malocclusion, or required orthodontic treatment or maxillofacial corrective surgery for maxillary hypoplasia. We concluded that a childhood nasal fracture treated by closed reduction does not have deleterious effects on facial or nasal growth.This work was supported in part by the Brigham Surgical Group Foundation, Inc., Boston, Massachusetts, USA  相似文献   
3.
This study presents the result of 12–21 years' follow-up in a group of children with neonatal urinary tract infection (onset within 1 month after birth) in whom early renal growth retardation was noted without concomitant classical renal scarring. In all cases the neonatal infection was diagnosed and treated within a few days of onset and the patients were closely supervised thereafter. Renal length, parenchymal thickness and area were measured at urography. At first follow-up (22 children, mean age 4.1 years) a significant reduction of renal parenchymal thickness was noted. Long-term follow-up (18 patients, mean age 17 years) demonstrated a normalization of renal size in the entire group, although less complete in the subgroup with reflux. There were two major findings in the present study. Firstly, renal growth retardation was seen after neonatal infection, both with and without reflux. Secondly, normalization of renal size in previously small kidneys was demonstrated, suggesting that growth retardation can be a reversible phenomenon. The tendency for such normalization was slightly more marked in children without reflux. Reduction of parenchymal thickness without calyceal deformity, therefore, does not necessarily mean irreversible damage, and differentiation between permanent scarring and temporary growth retardation can thus only be made at later follow-up, possibly not until after puberty. The demonstration of renal growth retardation in spite of early diagnosis and treatment emphasizes the great vulnerability of the kidney in the newborn.  相似文献   
4.
目的介绍个体成长模型方法对大学新生适应能力中交往主动性的3次测查数据采用普通回归模型和个体成长模型进行分析。结果个体成长模型的拟合度比普通回归模型的拟合度要好,个体成长模型可在个体水平上分析个体随时间产生的变化。结论个体成长模型具有许多优点,熟悉这种重要的分析方法对纵向数据研究者是非常有益处的。  相似文献   
5.
实验采用猪背部创伤模型,观察重组的碱性成纤维细胞生长因子(bFGF)对创伤修复的作用。在无菌条件下用特制打孔器在猪背部切割皮肤,形成2.5cm2的园型创面。将150个创面分成5组,分别以bFGF(60u/cm2创面),bFGF((60u/cm2创面)加SD-Ag、SD-Ag、生理盐水以及不治疗等方法处理,每间隔一天换药一次。实验结果表明,bFGF具有显著促进肉芽组织生长、加速创面再上皮化率以及增加创面愈合组织抗张力强度等作用。FGF显著促修复效应的确切机制尚不完全清楚,可能包括直接与间接效应两方面。  相似文献   
6.
Ten healthy subjects received buspirone (30 mg orally) with and without pre-treatment with the 5-HT1A receptor antagonist, pindolol (80 mg over 3 days). Following pindolol treatment the growth hormone and hypothermic responses to buspirone were significantly decreased. There was also a delay in the onset of the prolactin response to buspirone but the total amount of prolactin secretion, calculated as area under the curve, was not significantly reduced. The data suggest that the growth hormone and hypothermic responses to buspirone in humans are mediated by 5-HT1A receptors, but an explanation founded on pharmacokinetic factors cannot presently be excluded. Both this latter possibility and the lack of selectivity of pindolol for 5-HT receptors indicate the need for the further neuroendocrine studies of the mode of action of buspirone, preferably with more selective 5-HT1A receptor antagonists.  相似文献   
7.
Carbohydrate metabolism was evaluated by fasting and postprandial glucose, insulin, and hemoglobin (Hb)A1c levels in children with chronic renal insufficiency and various other growth disorders treated with growth hormone. Mean fasting and postprandial glucose remained unchanged throughout the 5-year study period in all four study groups. Median fasting insulin levels rose from lownormal levels into the normal range after 5 years of growth hormone. Average fasting insulin level after 5 years was 10 mU/l. Median postprandial insulin values also rose, yet remained within the normal range at the 5-year mark. Mean Hb A1c levels remained within low to middle end of the normal range in the patients with growth hormone deficiency, Turner syndrome, and idiopathic short stature. Mean Hb A1c levels at the 5 years were slightly elevated to 6.3% for the patients with chronic renal insufficiency.  相似文献   
8.
二十二碳六烯酸对神经细胞生长发育的影响   总被引:4,自引:0,他引:4  
目的:观察二十二碳六烯酸(DHA)对神经细胞生长发育的影响。方法:将无血清培养的新生大鼠大脑神经细胞分为实验组和对照组,实验组加入0.33mol/L乳化DHA 40μl。对两组细胞进行形态学观察及蛋白质含量测定。结果:实验组大脑神经细胞的突起生长速度、胞体面积和直径、神经细胞存活率及蛋白质含量均显著高于对照组。结论:DHA对神经细胞的生长有促进作用,这一作用可能与促进神经细胞蛋白质合成有关。  相似文献   
9.
目的为深入了解颅盖畸形目前在国内外研究中的进展情况,探讨颅缝早闭过程中相关生长因子的作用,为今后的研究工作奠定基础。方法应用计算机检索PubMed数据库,检索英文相关文章,同时检索中国期刊全文数据库的相关中文文章,并查阅相关书籍。对资料进行初审,并查看文献后的引文。纳入与颅盖畸形形成机制有关的内容,排除不相关及重复文章。结果经对收集文章的整理,共纳入23篇文献。对纳入的颅盖畸形形成机制的文献,结合目前国内外研究状况进行综述。结论进一步研究颅缝过早闭合及相关生长因子的作用,将有助于阐明颅盖畸形形成机制,并更好地指导临床治疗。  相似文献   
10.
目的:探讨急性肾功能衰竭的治疗。方法:复习有关急性肾功能衰竭的治疗文献,作一总结。结果:使用人工合成三肽序列(RGD)的多肽、生长因子、心房利钠因子和人工肾小管治疗急性肾功能衰竭都取得了较好的疗效。结论:这些新的治疗可望改善急性肾衰的预后和降低死亡率。  相似文献   
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