心脏黏液瘤的超微结构研究

对8例心脏黏液瘤进行了临床病理总结，着重进行了超微结构的研究，结果表明黏液瘤细胞有4种超微结构表现：（1）原始间叶细胞；（2）纤维母细胞样；（3）肌纤维母细胞样；（4）上皮样。提出心脏黏液瘤细胞起源于原始间叶细胞，有纤维母细胞、肌及上皮样分化。并且提出瘤细胞参与黏液瘤基质的形成。     

海洋低温溶菌酶对人脐静脉内皮细胞超微结构的影响

目的:观察海洋低温溶菌酶对体外培养的人脐静脉内皮细胞超微结构的影响,探讨海洋低温溶菌酶抗肿瘤血管形成的机制.方法:体外培养人脐静脉内皮细胞,用不同浓度的海洋低温溶菌酶处理24 h后,利用透射电镜观察细胞超微结构的变化.结果:海洋低温溶菌酶处理后人脐静脉内皮细胞出现超微结构变化,包括核内染色质浓缩及边集,胞质内细胞器肿胀和空泡化,呈现典型的细胞凋亡改变.这种改变呈剂量依赖性.结论:海洋低温溶菌酶可引起人脐静脉内皮细胞损伤,导致细胞凋亡,从而可能诱发其抗肿瘤血管生成的作用.     

多聚磷酸钠对牛背最长肌盐溶蛋白质热诱导凝胶保水性和超微结构的影响

本文以牛背最长肌为材料，采用L25(5^6)正交设计研究了焦磷酸二氢二钠、三聚磷酸钠和六偏磷酸钠对牛背最长肌盐溶蛋白质热诱导凝胶保水性和凝胶超微结构的影响。结果表明，在相同的离子条件下，添加的酸性焦磷酸钠或焦磷酸二氢二钠和三聚磷酸钠对热诱导凝胶保水性有极显著的影响(p＜0．0001和p＜0．0071)，而六偏磷酸钠的影响则不显著(p＞0．05)。值得注意的是，焦磷酸二氢二钠与六偏磷酸钠的交互作用、焦磷酸二氢二钠与三聚磷酸钠的交互作用、三聚磷酸钠与六偏磷酸钠的交互作用对热诱导凝胶保水性的影响极显著(p＜0．0001)，且比三聚磷酸钠的方差贡献大。Duncan多重比较显示，在盐溶蛋白质提取过程中，添加0．3％焦磷酸二氢二钠可使凝胶的保水性平均达到98．375％，比焦磷酸二氢二钠添加量为0．1％、0．15％和0．2％的凝胶保水性(分别为81．652％、84．384％和78．987%)高，差异显著(p＜0．05)。扫描电镜研究结果显示，保水性不同的凝胶其超微结构表现出很大的差异。保水性为99．5％的凝胶其凝胶结构致密，均匀，网格细小，而且线条较纫，边缘平滑。而保水性为90%的凝胶则结构粗糙，表现为线条较粗，不均匀，蛋白质交联较少，网格大且不一致。线条多呈平行排列，或以聚集状态存在。     

Effect of cooking temperature on texture and flavour binding of braised sauce porcine skin

To investigate the effect of cooking temperature (55, 65, 75, 85 and 95 °C) on texture and flavour binding of braised sauce porcine skin (BSPS), sensory acceptance, microstructure and flavour-binding capacity were investigated during the processing of BSPS. Samples cooked at 85 and 95 °C showed better texture and aroma scores. Hardness and chewiness of BSPS were obviously improved at 85 and 95 °C than control group. Collagen structure was significantly destroyed over 85 °C. The porcine skin collagen heated at 85 and 95 °C showed relatively higher flavour-binding capacity than other samples. The improvement of texture of BSPS was mainly attributed to the degradation of collagen. Higher aroma scores of BSPS were related to intense binding abilities with aroma compounds at 85 and 95 °C. Cooking at 85 or 95 °C could be an optimal cooking temperature for BSPS.     

电子束剂量率对冷却牛肉蛋白品质和感官特性的影响

为探究电子束剂量率对充氮包装冷却牛肉微观结构、蛋白品质及感官特性的影响,取牛背最长肌,在高能电子加速器下辐照处理,4℃贮藏25 d。评估辐照剂量率和贮藏时间对其微观结构、蛋白品质及感官特性的影响。在贮藏初期,试验组和对照组相比,冷却肉表面色泽较暗,具有一定的辐照异味,感官得分相对较低,随着贮藏时间的延长,对照组的感官得分下降,辐照处理组相对稳定,150 k Gy/min处理组感官得分相对较高。辐照处理可以在一定程度上加速冷却牛肉的成熟,150 k Gy/min辐照处理对肌节长度的影响与未辐照处理组贮藏成熟15 d对肌节长度的影响相近。电子束辐照对冷却牛肉蛋白质含量及氨基酸组分无显著性影响,而贮藏时间对赖氨酸和缬氨酸等必须氨基酸的含量有显著性影响。     

Inhibitory of multiple antifungal components produced by Lactobacillus plantarum K35 on growth,aflatoxin production and ultrastructure alterations of Aspergillus flavus and Aspergillus parasiticus

The antifungal activity of Lactobacillus plantarum K35 isolated from traditional Thai fermented rice noodle was evaluated against the growth and aflatoxin production of Aspergillus flavus TISTR304 and Aspergillus parasiticus TISTR3276. Multiple antifungal compounds secreted by L. plantarum were firstly analyzed using GC–MS in parallel to the ultrastructure alteration of the treated fungi. L. plantarum K35 supernatant caused significant reduction of the fungal growth and aflatoxin production. The antifungal activity was pH-dependent and favorable to acidic conditions whereas the catalase treatment had no influence indicating no involvement of hydrogen peroxide in the inhibition. Antifungal substances were resistant to sterilization and proteolytic enzymes including trypsin and proteinase K. The major components, apart from lactic acid, were 2-butyl-4-hexyloctahydro-1H-indene (19.55%), oleic acid (10.52%) and palmitic acid (7.27%). Other minor antifungal compounds included linoleic acid (2.11%), 2,4-di-tert-butylphenol (1.84%), stearic acid (1.55%), 3-phenyllactic acid (1.42%) and pyroglutamic acid (1.07%). The morphological changes of the fungi exposed to the supernatant were observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). L. plantarum K35 supernatant caused severe damage to the cell wall and cytoplasmic membrane leading to a massive loss of cytoplasmic content, the formation of membrane-bound vesicles, and complete destruction of membranous organelles including mitochondria and nucleus.     

极危孑遗蕨类中华水韭叶结构的系统学意义

水韭属是濒危的孑遗植物,是研究古生态及其物种演化的活化石。本文用扫描电子显微镜和透射电子显微镜观察了中华水韭叶片的结构特征,首次报道了:(1)通气道横隔细胞在同一平面以5~7个放射状短臂相互连接,且细胞表面有数百个微纤毛;(2)叶表皮为复表皮;(3)光合细胞以5~7个短臂在3D空间相互连接;(4)叶脉不分支,管胞的环纹与初生壁间另有连接结构,管胞周围有薄壁细胞紧密包围;(5)舌足与叶肉嵌合处各有表皮;(6)自气孔下室观察了气孔器的内侧结构,为气孔研究拓展了视野。认为水韭属叶片的超微3D结构具有稳定的特殊性和复杂性,与近源的石松科及卷柏科相差甚远,证明水韭有孤立的演化路线。