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11.
To study the effects of suture material, calibre and tension on the end-to-end oesophageal anastomosis, the cervical oesophagus of the rat was resected for 2.5 mm, 7.5 mm and 12.5 mm respectively in three groups of 60 rats each. End-to-end anastomosis was performed with either 6/0 silk, 6/0 polypropylene or 9/0 polypropylene sutures. There was no postoperative leakage. Mortality was mainly due to hair bolus obstruction at the site of anastomosis. There was no difference in mortality and anastomotic stenosis between groups with different resection lengths. Within each group, however, mortality and anastomotic stenosis were significantly higher in the subgroup of rats with 6/0 silk suture than that in the subgroup with 6/0 polypropylene sutures, which also had significantly higher mortality and anastomotic stenosis than the subgroup with 9/0 polypropylene sutures. Histological examination of the stenosed anastomosis showed disruption of muscle layers and submucosal thickening. It is concluded that the use of fine calibre sutures of biologically inert material would be preferred for the end-to-end anastomosis of the oesophagus. 相似文献
12.
阿昔洛韦对单纯疱疹病毒脑炎小鼠脑细胞的保护作用 总被引:1,自引:0,他引:1
目的 了解单纯疱疹病毒脑炎(HSE)脑细胞结构的改变及药物的影响。方法 采用光学显微镜及透射电子显微镜观察HSE小鼠脑细胞结构的变化,并给予阿昔洛韦(ACV)及地塞米松(DEX)治疗,观察治疗后脑细胞结构的变化。结果 HSE小鼠脑神经细胞明显肿胀,核仁固缩,核内结构破坏,线粒体及高尔基体可见空泡样变性,核仁内可见病毒颗粒。用药物干预的小鼠脑神经细胞改变较轻微,未找到病毒颗粒;与单用ACV干预的小鼠相比,用ACV DEX干预的小鼠脑神经细胞及毛细血管周围水肿明显减轻。结论 HSE早期给予ACV DEX治疗,对HSE脑细胞结构有明显保护作用。 相似文献
13.
Beryl Smith Ph.D. Man Cheung Chung Panos Vostanis 《Journal of autism and developmental disorders》1994,24(5):551-563
Parents of children with autism often report problems associated with obtaining a diagnosis of their child's condition, family support, information, and appropriate services. To evaluate any changes in the situation over the last two decades, the families of all members of the West Midlands Autistic Society, age 19 years and below, were asked to fill in a questionnaire that covered aspects of detection, diagnosis, help and information received, and educational provision. Responses were obtained from 127 families, the children of whom formed an older group ages 10 years and above (n=67) and a younger group ages 9 years and below (n=61). Findings show that there have been improvements for the younger group in some areas, such as earlier referral, diagnosis, and statementing. However, the situation with respect to advice given by professionals and the support and provision available after referral is still much the same as that experienced by families of the older group of children. Many difficulties and hurdles remain which hinder parents and children on the path to care in autism. 相似文献
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Camus Kar Man Choy Pauline Cho Wai-Yuen Chung Iris F F Benzie 《Optometry and vision science》2003,80(9):632-636
BACKGROUND: Tear ascorbate is important for corneal health. A rapid and simple method for measurement of ascorbate in tears is needed, and adequate knowledge of physiological variation of tear ascorbate is important to facilitate comparative studies of the effect of, for example, contact lens wear and environmental conditions and stresses. However, there are currently no data on physiological variation of tear ascorbate. This study validated a simple and speedy method for tear ascorbate and investigated between-eye and between-day variation in tear ascorbate in healthy young adults. METHODS: Yawn-induced reflex tears were collected from 32 healthy Hong Kong Chinese subjects and measured by both high-performance liquid chromatography (HPLC) and by an enzyme-linked colorimetric method known as FRASC (total ferric reducing (antioxidant) activity and ascorbate concentration measurement). For between-eye variation, yawn reflex tears were collected from each eye of the same 32 healthy subjects, and ascorbate was measured using HPLC; in a separate experiment for between-day variation, tears were collected on two separate days from 14 subjects, and ascorbate was measured by FRASC. RESULTS: Both HPLC and FRASC showed high precision, and results obtained using FRASC were not statistically different from those using HPLC; mean +/- SD were, respectively, 18.5 +/- 4.4 microM and 18.5 +/- 4.8 microM for HPLC and FRASC methods (p = 0.943). No significant between-eye difference in tear ascorbate was found (p = 0.386), and no significant between-day variation was found overall: mean +/- SD ascorbate was 20.0 +/- 6.2 microM on day 1 and 19.3 +/- 6.8 microM on day 2 (p = 0.772). However, between-day variation was large in seven of 14 subjects. CONCLUSION: FRASC is an acceptable alternative to HPLC for measurement of tear ascorbate. Tears for ascorbate investigation can be collected from either eye or, if necessary, from both eyes and pooled. However, tear ascorbate may vary widely from day to day in the same individual. The reasons for this variation require further study but may relate to differences in ascorbate supply or demand within the precorneal tear layer. 相似文献
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17.
目的:探讨内皮细胞清除补体攻膜复合物(MAC)的途径及其清除动力学,方法:原代培养的人脐静脉内皮细胞以RH414荧光标记质膜双层,0℃组装亚溶剂量的MAC,37℃复苏后,LSCM实时监MAC沉积诱导的质膜囊泡化形成和胞吞,胞吐情况,流式细胞仪定量检测内皮细胞表面MAC抗原的清除情况,结果:MAC沉积后,内皮细胞有的质膜囊泡化形成,囊泡以胞吞和胞吐2种方式离开细胞,并以前者占优,37度条件下,内皮细胞清除表面MAC的半衰期约为5min。结论:内皮细胞可通过胞吞和胞吐2种机制清除细胞表面沉积的MAC,并以胞吞方式为主。 相似文献
18.
军校研究生自我效能感和主观幸福感的关系研究 总被引:2,自引:0,他引:2
目的探讨军校研究生自我效能感与主观幸福感之间的关系。方法采用幸福感指数量表和自我效能感问卷对281名军校研究生进行调查。结果①军校研究生的自我效能感与正性情感、负性情感和总体幸福感存在显著的相关关系,与生活满意度相关不显著;②高自我效能感和低自我效能感组在正性情感、负性情感和总体幸福感上均存在着显著的差异;③自我效能感分别进入正性情感、负性情感和总体幸福感的回归方程,对其均有较好的预测作用,其中对正,巨情感的预测更佳。结论军校研究生的自我效能感与正性情感、负性情感和总体幸福感存在显著的相关关系,对其有较好的预测作用,其中自我效能感与正性情感成分联系更为密切,预测作用更佳。 相似文献
19.
目的 构建绿色荧光蛋白标记的MHCⅠ类分子K^b(K^b-EGFP融合蛋白),并在哺乳动物细胞中获得功能性表达。方法 RT-PCR的方法获得小鼠MHCⅠ类分子K^b cDNA,克隆入真核表达载体pEGFP-N1中EGFP分子的上游,脂质体转染COS-7细胞,G418加压筛选获得抗性重组细胞。荧光显微镜下观测重组分子的表达及胞内定位情况。结果 分子克隆的方法获得了预期的重组质粒,质粒经DNA序列测定证实阅读框无误,转染COS-7细胞后的抗性克隆胞浆内可以观察到明亮的绿色荧光,特征性地分布于细胞质膜,及核周、膜下的囊泡结构中。结论 所构建的K^b-EGFP融合蛋白在细胞内表达后具有MHCⅠ类分子的特征性分布,提示该重组分子具有野生型MHCⅠ类分子的生物学特性和胞内分布特征,为进一步深入研究MHCⅠ类分子胞内动态分布及分子功能提供了良好的细胞和分子模型。 相似文献
20.
Interleukin-6 induced at mucosal surfaces by gram-negative bacterial infection. 总被引:12,自引:15,他引:12 下载免费PDF全文
P de Man C van Kooten L Aarden I Engberg H Linder C Svanborg Edn 《Infection and immunity》1989,57(11):3383-3388
Interleukin-6 (IL-6) was produced in response to mucosal and systemic infection of mice with gram-negative bacteria. The IL-6 response was controlled by the lipopolysaccharide gene, Lps; in C3H/HeN mice (Lpsn/Lpsn), the urinary IL-6 levels increased within 30 min after challenge with Escherichia coli, but no response occurred in C3H/HeJ mice (Lpsd/Lpsd). In lipopolysaccharide-responder mice, the levels of local and systemic IL-6 were related to the degree of infection. The urinary response dominated after intravesical challenge, and the serum response dominated after intraperitoneal challenge. The results demonstrate that IL-6 is activated as part of lipopolysaccharide-induced mucosal and systemic responses to gram-negative bacterial infections. 相似文献