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991.
由聚酯二元醇、异佛尔酮二异氰酸酯和二羟甲基丙酸合成聚氨酯预聚体,以氨乙基氨丙基聚二甲基硅氧(AEAPS)为扩链剂,制备了AEAPS改性聚氨酯水分散液。与未改性的聚氨酯水分散液相比,AEAPS改性聚氨酯水分散液的粒径增大,但粒径分布和表面张力基本不变,说明疏水的聚二甲基硅氧烷侧链被包裹于分散颗粒的内部;此外,改性聚氨酯水分散液的冻融稳定性显著增强。AEAPS改性聚氨酯水分散液成膜后,吸水率明显下降,水在膜表面的接触角增加,400℃时热失重下降,具有良好的疏水性和耐热性。 相似文献
992.
Yasushi Nishihira Chun‐Feng Tan Junko Hirato Junichi Yoshimura Kenichi Nishiyama Hideaki Takahashi Yukihiko Fujii Hitoshi Takahashi 《Neuropathology》2007,27(6):551-555
Two embryonal CNS tumors, atypical teratoid/rabdoid tumor (AT/RT) and primitive neuroectodermal tumor (PNET), may be confused with each other and misdiagnosed. Here we report an infant with a congenital supratentorial tumor, which was detected by fetal MRI at 37 weeks gestation. On routine histological examination, the tumor was composed mainly of small undifferentiated cells, among which many rhabdoid cells and occasional sickle‐shaped embracing cells were observed. No mesenchymal or epithelial areas were evident. Our impression was that the tumor was an atypical example of AT/RT. Immunohistochemically, almost all the tumor cells were strongly positive for vimentin. However, epithelial membrane antigen was notably negative, and most of the tumor cell nuclei were clearly positive for INI1. In addition, many tumor cells were positive for neurofilament protein. There were also occasional small areas containing many tumor cells positive for glial fibrillary acidic protein. Finally, a diagnosis of PNET, with a rhabdoid phenotype and expression of neuronal and glial markers, was made. In the present case, application of INI1 immunostaining was very helpful for distinguishing PNET from AT/RT. 相似文献
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997.
Yasushi Sano Hirohisa Machida Kuang‐I. Fu Hiroaki Ito Takahiro Fujii 《Digestive endoscopy》2004,16(Z1):S93-S96
The goal of endoscopic mucosal resection (EMR) is to allow the endoscopist to obtain tissue or resect lesions not previously amenable to standard biopsy or excisional techniques and to remove malignant lesions without open surgery. In this article, we describe the results of conventional EMR and EMR using an insulation‐tipped (IT) electrosurgical knife (submucosal dissection method) for large colorectal mucosal neoplasms and discuss the problems and future prospects of these procedures. At present, conventional EMR is much more feasible than EMR using IT‐knife from the perspectives of time, money, complication, and organ preservation. However, larger lesions tend to be resected in a piecemeal fashion; and it is difficult to confirm whether EMR has been complete. For accurate histopathological assessment of the resected specimen en bloc EMR is desirable although further experience is needed to establish its safety and efficacy. Further improvements of in EMR with special knife techniques are required to simply and safely remove large colorectal neoplasms. 相似文献
998.
目的 研究原核表达及纯化、复性的重组人白介素24蛋白(recombined human interlukin 24,rhIL-24)对荷人A375细胞黑素瘤裸鼠的抑制肿瘤生长的作用.方法 将人A375黑素瘤细胞注射至裸鼠体内,待肿瘤生长到一定体积后,向裸鼠的肿瘤内注射rhIL-24,2周后切取肿瘤称重、量体积,进行病理检查及免疫组化检测.结果 经rhIL-24注射的肿瘤体积及重量与对照组相比明显减小、减轻;Bax基因表达上调、Bcl-2、CD34及VEGF基因表达下调,显示肿瘤细胞生长受到抑制,凋亡率增加.结论 rhIL-24对荷人A375细胞黑素瘤裸鼠的肿瘤有显著抑制生长的功能,可促进A375细胞凋亡,而对裸鼠则无明显的不良反应. 相似文献
999.
Ming-Shian Tsai Wen-Hsi Lin Wen-Ming Hsu Hong-Shiee Lai Po-Huang Lee Wei-Jao Chen 《Journal of gastrointestinal surgery》2008,12(12):2191-2195
Background/aims Surgical resection of choledochal cysts (CC) has become standard treatment. However, surgery is not universally recommended
in early infancy and/or asymptomatic patients. In order to investigate the optimal timing of CC excision, we analyzed clinicopathological
data and surgical results from different age groups.
Material and methods This retrospective review included 107 patients (77 females, 30 males) who underwent CC resection at the National Taiwan University
Hospital between January 1988 and December 2005. Patient demographic, clinical, and surgical data were collected and analyzed.
Results The patients were divided into three groups according to age at the time of surgery: <1 year old (group I, n = 26), 1−16 years old (group II, n = 48), and >16 years old (group III, n = 33). About two thirds of the patients in group I had jaundice, while abdominal pain related to inflammation was the commonest
symptom in groups II and III. Group I suffered significantly fewer surgical complications and less severe liver fibrosis than
groups II or III.
Conclusion CC surgery in infancy and in asymptomatic patients is safe and may prevent the complications of this condition. The results
support a recommendation for early excision. 相似文献
1000.
血清铁和铁蛋白与肝病患者肝纤维化指标的关系 总被引:12,自引:1,他引:11
OBJECTIVE: To study the relationship of serum iron and ferritin with the indicators for hepatic fibrosis and hepatic iron overload. METHODS: Liver tissue specimens were obtained from 41 patients with benign (16) or malignant (25) liver diseases by 1 second liver biopsy, and routine microscopic examination was performed after haematoxylin-eosin (HE) and Perl's Prussian staining. Atomic absorption spectrum, radioimmunoassay and enzyme-linked immunosorbent assay were respectively employed to examine the serum levels of iron, ferritin, hyaluronic acid, laminin, human procollagen type , and collagen type . RESULTS: Between patients with benign and malignant liver diseases, significant differences were found in the serum ferritin levels (P < 0.05), but not in serum iron levels (P > 0.05). It was also noted that the levels of the indicators for hepatic fibrosis in patients with benign and early-stage malignant diseases varied significantly from the levels in normal subjects, but these differences were not observed between normal subjects and patients with end-stage hepatic malignancies. Serum iron and ferritin were found to be associated with serum laminin levels (serum iron: r=0.439, P=0.031; serum ferritin: r=0.476, P=0.016), and no iron granules detected in the tissue specimens of hepatocellular carcinoma. CONCLUSIONS: Most of the patients with hepatocellular carcinoma have elevated serum ferritin levels. The serum levels of iron and ferritin are statistically correlated with serum laminin level. Obvious reduction of iron content is typical of hepatic malignant tissues in comparison with the benign tissues, and the reduction in the levels of the indicators for hepatic fibrosis might involve the inhibition of collagen synthesis in the tumor tissues from patients with end-stage hepatocellular carcinoma. Most of the cases of alcoholic fatty liver are complicated by liver iron overload, often marked by serum iron and ferritin levels. 相似文献