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81.
低溶胀壳聚糖/丝素蛋白复合膜的制备及性能测试 总被引:1,自引:0,他引:1
为改善单纯壳聚糖膜用作医用创面敷料在湿环境下的力学性能,将壳聚糖(CS)和家蚕丝素蛋白(SF)混合,采用延流法制备壳聚糖/丝素蛋白(CS/SF)复合膜。物理与机械性能测试表明:CS/SF复合膜的溶胀率较单纯CS膜显著降低,且其溶胀能力具有pH依赖性;CS/SF复合膜的水蒸气透过率较单纯CS膜略有下降,但仍保持在2 043~3 363 g/(m2.d);CS/SF复合膜在湿环境下的力学强度较单纯CS膜显著提高,当加入SF的质量分数为15%时,复合膜的力学性能最好,其拉伸强度为34.5 MPa±1.8 MPa,比单纯CS膜提高近18%,而其断裂伸长率也由初始的83.1%±6.7%提高到119.3%±8.2%。CS/SF复合膜具有较好的药物释放性能,对抗感染药物盐酸万古霉素表现出在初始1 h内的突释行为和随后较长时期的缓释行为,十分有利于降低感染和加速伤口愈合。此外,CS/SF复合膜对STO小鼠胚成纤维细胞具有良好的生物相容性。各项性能测试显示CS/SF复合膜作为医用敷料具有潜在的应用前景。 相似文献
82.
小鼠眼睑发育需要表皮角质形成细胞的增殖、分化、凋亡及迁移的协调作用。表皮角质形成细胞是研究眼睑闭合不全机制重要的细胞模型。表皮角质形成细胞培养时,贴壁差,增殖力低,生活力弱,生长条件要求高,传代次数有限。对近年来表皮角质形成细胞的体外培养方法及其在遗传性眼睑闭合不全研究中的应用进行综述,以期为表皮角质形成细胞的长期培养和研究人类先天性眼睑发育缺陷机制提供参考。 相似文献
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The effects of soil water availability on suberin lamellae formation in the endodermis and exodermis and the occurrence of cell wall thickening in the cortex in red bayberry (Myrica rubra Sieb. et Zucc.) tree roots were examined during tissue aging. For several months, red bayberry trees were grown in small baskets under dry, normal, and waterlogged soil water conditions. Transverse sections of roots from 5 mm from the tip to the basal portion were stained with several staining solutions and the cell structure was observed. Root anatomical development was significantly changed by soil water conditions. The suberin lamellae in the endodermis formed later in plants grown under dry conditions than in those grown under waterlogged conditions. Cell wall thickening in the cortex near the endodermis was promoted by drought, but apparently not by waterlogged conditions. 相似文献
86.
云南昭通是南方重要的苹果生产基地,但由于主栽晚熟红富士品种比例过高,给生产销售等方面带来一系列问题,为解决品种单一带来的各种问题,充分发挥当地苹果比北方苹果成熟早的自然优势,从2006年起我们开始从烟台引试种植红露等中早熟品种,希望从中找出表现良好的品种来发展,以调整昭通苹果品种结构。试种的红露苹果于2009年投产,具有早果、丰产、色艳、果个大、极耐贮运、抗逆性强等特性,具有良好的发展前景。 相似文献
87.
Fractalkine has been recognized as the first member of the fourth chemokine family recently and its receptor, CX3CR1, was ident ified afterwards. This pair of ligand/receptor play important roles in the migration and adhesion of peripheral leukocyte through different ways. They are also likely to be related to the embryogenesis and regeneration of several organs and may possess some functions in the central nervous system. 相似文献
88.
Sakamoto K Lewbart GA Smith TM 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2001,30(2):50-52
Abstract: Blood samples were collected from 29 juvenile red pacu ( Piaractus brachypomus ), ornamental freshwater fish, to establish baseline blood chemistry values. Mean (minimum-maximum) values, obtained by automated bichromatic analysis and ion selective electrode analysis, were as follows: sodium, 150.4 (146–159) mmol/L; potassium, 3.93 (2.7–5.0) mmol/L; chloride, 138.7 (128–150) mmol/L; total CO2 , 7.5 (6–10) mmol/L; albumin, 0.86 (0.5–1.0) g/dL; lactate dehydrogenase, 237.8 (65–692) IU/L; aspartate aminotransferase, 49.1 (0–125) IU/L; creatinine, 0.31 (0.2–0.4) mg/dL; calcium, 10.80 (9.5–12.5) mg/dL; anion gap, 6.89 (1.2–12.5) mmol/L; and phosphorus, 7.29 (4.1–8.9) mg/dL. 相似文献
89.
Nurun Nahar Khanam Junichi Kihara Yuichi Honda Toshihide Tsukamoto Sakae Arase 《Journal of General Plant Pathology》2005,71(4):285-288
When detached broad bean leaves were preinoculated with virulent strain B304 of Botrytis cinerea 24 h before a challenge inoculation with strain B304, lesion formation by B304 was significantly inhibited in red light but not in the dark. In leaves that were preinoculated with avirulent strain 021 and then challenged by B304, however, lesion formation was not inhibited even under red light. Such differences in lesion formation after the challenge inoculation with an avirulent strain were also observed with lesions caused by Alternaria alternata, a nonpathogen of broad bean and by avirulent strain 021R in the presence of germination fluid from spores of strains B304 and 021R. These results suggest the possibility that virulent B. cinerea produced a suppressor involved in induced susceptibility and an elicitor involved in resistance induced by red light during spore germination. 相似文献
90.
AIM: This study was designed to investigate the inhibition of tanshinone ⅡA on C6 glioma cell line and its mechanism. METHODS: MTT was used to measure the levels of the proliferation of C6 cultured with tanshinone ⅡA at different concentrations. The effects of tanshinone ⅡA on cell cycle of C6 were observed by FCM. The change of DNA was observed by Sepharose electrophoresis. The expression of proto-oncogenes c-myc was measured by RT-PCR. RESULTS: The proliferation of C6 was obviously inhibited by tanshinone ⅡA in a dose-dependent manner. The outcome of FCM showed that the apoptotic cell rate was 7.7%, when cultured with tanshinone ⅡA at 1.0 mg/L for 3 days. The apoptotic cell rate was 21.6%, when cultured with tanshinone ⅡA at 2.0 mg/L in 3 days. CONCLUSION: Tanshinone ⅡA inhibits the proliferation of C6 cells, induces apoptosis and inhibits the expression of proto-oncogene c-myc. 相似文献