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121.

Background  

Improved survival due to advances in neonatal care has brought issues such as postnatal growth and development more to the focus of our attention. Most studies report stunting in children born very preterm and/or small for gestational age. In this article we study the growth pattern of these children and aim to identify factors associated with postnatal catch-up growth.  相似文献   
122.
123.
腹腔镜外科和妇科联合手术的临床应用   总被引:1,自引:0,他引:1       下载免费PDF全文
目的:探讨腹腔镜技术在外科和妇科疾病治疗中联合应用的临床价值。 
方法:总结近7年来施行腹腔镜联合手术治疗妇、外科疾病229例的临床资料,其中腹腔镜胆囊切除术(laparoscopic cholecystectomy,LC)联合输卵管造口术5例,LC联合卵巢囊肿剥除术28例,LC联合子宫肌瘤剔除术25例,LC联合子宫次全切除术39例,LC联合子宫全切除术26例,LC联合子宫内膜异位症手术6例;腹腔镜阑尾切除术(laparoscopicappendectomy,LA)联合输卵管手术38例,LA联合卵巢囊肿切除术32例,LA联合子宫全切除术或子宫次全切除术24例,腹腔镜肝囊肿开窗引流术联合卵巢囊肿切除术6例。
结果:229例妇、外科联合腹腔镜手术均获成功,无中转开腹手术。手术时间40~220 min,平均120 min;住院1~6 d,平均3.4 d。仅1例术后10 d阴道残端出血非手术疗法治愈。175例随访3~24个(平均19.5)月,1例术后2个月发现阴道残端息肉,经手术切除治愈。 
结论:严格掌握联合手术指征,充分术前准备,多科室良好配合,腹腔镜联合手术能够有效地同时处理外科和妇科并存疾病,在基层医院具有良好的应用前景。  相似文献   
124.
日本血吸虫SjCa8基因的原核表达及其免疫学特征分析   总被引:2,自引:0,他引:2  
目的表达和纯化日本血吸虫钙结合蛋白(SjCa8),研究其免疫学特征。方法重组质粒pET32a ( )-SjCa8经诱导表达后,获取纯化蛋白SjCa8,利用ELISA、Western-blot和动物保护性实验检测SjCa8的免疫学特征。结果成功获取了纯化蛋白SjCa8,该蛋白能免疫识别血吸虫感染小鼠血清和血吸虫病患者血清。SjCa8免疫Balb/c小鼠可获得较高滴度的特异性抗体,诱导宿主产生35.31%的减虫率和35.68%的减卵率。结论纯化蛋白SjCa8具有良好的免疫原性和免疫反应性,具有作为血吸虫病免疫诊断和疫苗候选分子的研究价值。  相似文献   
125.
Soybean phytate content: effect on calcium absorption   总被引:4,自引:0,他引:4  
Absorption of calcium from soybeans with low and high phytate contents, intrinsically labeled with 45Ca, was measured in 16 normal women and compared in 15 of these same subjects with absorption of calcium from labeled milk. The average test load of calcium for all three sources was 2.45 mmol. Fractional calcium absorption (+/- SD) from the high-phytate soybeans averaged 0.310 +/- 0.070; from the low phytate soybeans, 0.414 +/- 0.074; and from milk, 0.377 +/- 0.056. The mean difference (+/- SEM) in fractional calcium absorption for the two phytate levels was 0.104 +/- 0.014 (P less than 0.001).  相似文献   
126.
目的:观察椎板切除术后用几丁糖(CHT)的同时在椎板缺损处植入磷酸三钙人工骨(TCP)预防硬膜外瘢痕粘连的效果。方法:40只纯种日本大耳白兔随机分成A、B、C、D四组,制作L4椎板损伤模型。A组硬膜外涂布生理盐水,B组硬膜外涂布几丁糖,C组硬膜外覆盖人工骨,D组硬膜外涂布几丁糖的同时加人工骨覆盖。术后12周对椎板切除部位进行大体观察、组织学观察及生化检查,比较各组间瘢痕形成和粘连情况。结果:B、C、D组的改良Rydell-Balazs粘连韧度评分、胶原含量及改良Nussvaum组织学评分均优于A组(P<0.01),D组优于B组与C组(P<0.05),B组与C组无显著性差异(P>0.05)。结论:联合应用几丁糖和人工骨能有效预防硬膜外瘢痕粘连的形成,比单独应用几丁糖和人工骨预防效果好。  相似文献   
127.
Ohh  M; Smith  CA; Carpenito  C; Takei  F 《Blood》1994,84(8):2632-2639
Although the intercellular adhesion molecule-1 (ICAM-1) is constitutively expressed at a low level on a subpopulation of hematopoietic cells, on vascular endothelium, on fibroblasts, and on certain epithelial cells, it is dramatically increased at sites of inflammation. Interferon-gamma (IFN-gamma) and phorbol myristate acetate (PMA) are known to increase the expression of ICAM-1 on many cell types. Because both human and murine ICAM-1 mRNAs contain putative destabilizing AUUUA sequences in their 3' untranslated regions (UTRs), we examined the role of mRNA stability in the regulation of ICAM-1 gene expression. The treatment of the murine monocytic cell line P388D1, which constitutively expresses ICAM-1 mRNA at a low level, with IFN- gamma or PMA rapidly enhanced the level of ICAM-1 mRNA and dramatically prolonged its half-life. To determine whether the putative destabilizing sequences are responsible for this effect of IFN-gamma and PMA, fibroblast L cells were transfected with either the full- length ICAM-1 cDNA or a truncated form (ICAM-1 delta 3) lacking the putative destabilizing AUUUA sequences. Although ICAM-1 delta 3 mRNA was more stable than the full-length ICAM-1 mRNA, IFN-gamma treatment induced the accumulation of both mRNA species and prolongation of their half-lives. The transplantation of the ICAM-1 delta 3' UTR into a stable ICAM-2 mRNA rendered it unstable, and it was unresponsive to IFN- gamma. Therefore, the treatment with IFN-gamma stabilizes the otherwise labile ICAM-1 mRNA, but the IFN-gamma-responsive sequence may at least in part reside within the protein coding region. PMA also upregulated ICAM-1 gene expression by mRNA stabilization. However, unlike IFN- gamma, PMA treatment only increased the level of the full-length, but not of the truncated, ICAM-1 mRNA. This shows that the PMA-responsive element is located within the 3'UTR. Furthermore, the effect of PMA on ICAM-1 delta 3 mRNA was recovered by ligating multiple AUUUA sequences derived from a heterologous gene fragment. The stability of this chimeric mRNA and the full-length ICAM-1 mRNA was markedly increased by PMA treatment, indicating that the AUUUA multimers in the 3'UTR are important in the PMA-induced upregulation of ICAM-1 mRNA.  相似文献   
128.
目的观察变应性鼻炎(AR)脱敏治疗的效果,探讨影响变应性鼻炎脱敏治疗效果的相关因素。方法对185例AR患者通过皮肤试验,选择敏感变应原浸液,按递增剂量进行常规皮下脱敏治疗。根据患者治疗前后的症状和体征得分情况,分为显效、有效和无效。选择性别、年龄、病程、病情、伴慢性鼻窦炎、伴哮喘、脱敏治疗时间、皮试反应等8个影响变应性鼻炎脱敏治疗效果的可能因素进行多元回归分析,筛查影响脱敏治疗效果的因素。结果总有效率74.6%,其中显效22.9%,有效51.7%。影响脱敏治疗效果的主要因素是治疗时间,即时间越长,效果越好(P〈0.01);其次是年龄因素,年龄越小,效果越好(P〈0.05);伴慢性鼻窦炎和伴哮喘也可能影响脱敏治疗效果(P值分别为0.072和0.069)。结论变应性鼻炎脱敏治疗是有效的,脱敏治疗时间越长、年龄越小,效果越好。  相似文献   
129.
ABSTRACT

The North American Guidelines for Children's Agricultural Tasks (NAGCAT) were developed to reduce the risk of childhood agricultural injury. The purpose of this study was to evaluate compliance with NAGCAT-recommended work practices (WPs) when youth work with large animals. On a daily basis, over a period of 10 weeks, youth self-reported the number of minutes they worked with a large animal and whether they followed the associated NAGCAT WP guidelines. Statistical analyses were conducted to compare boys to girls and to consider the effect of factors such as youth age, farm residence status, and selected parental characteristics. A high proportion of youth exhibited relatively low compliance for most of the five WPs evaluated. Respirators were rarely worn, but checking for people and obstacles in the area while working with large animals was commonly reported. In general, boys, especially the older boys, exhibited higher compliance than did girls. The results of our study demonstrate, in general, that youth are not following recommended NAGCAT WPs when working with large animals, identifying an area in agricultural safety and health requiring focused attention.  相似文献   
130.
Digital beam attenuator technique for compensated chest radiography   总被引:1,自引:0,他引:1  
The feasibility of producing patient-specific beam attenuators for chest radiography has been investigated using an anthropomorphic phantom and a human volunteer. A low-dose test exposure is digitized, processed, and used to print a small cerium filter, which is placed in the x-ray beam near the collimator. The final radiograph is recorded on film. The technique results in relatively uniform film exposure, so that structures in all regions of the chest are simultaneously displayed with optimal film contrast. The equalized exposure improves image quality in the normally underpenetrated regions and reduces the role of cross-scatter from the lungs. The image is analogous to optical or computer-processed unsharp masking techniques, but the processing is accomplished in the x-ray beam and results in an improved exposure distribution, giving advantages that cannot be achieved with image processing techniques alone.  相似文献   
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