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11.
Occlusal morphology of permanent dentitions in 29 men with a 47,XXY chromosome complement (Klinefelter syndrome) was determined from dental casts. The results showed that a relatively frequent occlusal anomaly was mesial molar occlusion. Incisal open bite was also more common than in controls. Based on the present and previous observations of occlusal anomalies in various sex chromosome anomaly groups and normal controls, it is suggested that the presence of the Y chromosome in the genome is at least as important as the X chromosome for the development of harmonious occlusal morphology. The tendency towards sexual dimorphism in occlusal phenotype might result from a differential effect of the X and Y chromosomes on cellular activity which leads to different growth patterns. 相似文献
12.
本文采用非选择性培养基对22名健康青少年的唾液、沟裂菌斑、龈上菌斑及龈下菌斑中的需氧菌、兼性厌氧菌及专性厌氧菌进行了分离培养,并计算其在不同标本中占可培养菌的百分比及检出率。结果共分离到包括18个菌属的35种细菌。其中,链球菌、放线菌、奈瑟氏球菌、二氧化碳噬纤维菌、类杆菌、梭杆菌,奴卡氏菌及棒状杆菌在口腔4个部位的检出率及所占比例均较高,是健康青少年口腔中的优势菌群.通过比较还发现,其中一些菌在口腔4个部位的分布存在一定差异.本文还采用刚果红负性染色涂片法,镜下观察龈上、龈下菌斑中的螺旋体,并计算其相对比例.结果龈下菌斑中螺旋体的相对比例明显高于龈上菌斑. 相似文献
13.
中药903口服液经药效学研究,表明该制剂具有良好的扶植正常菌群,调整微生态平衡,提高机体免疫能力的作用。对中药903口服液进行长期毒性实验研究结果证实,三种不同剂量组大白鼠给药前后的体重,血常规,主要脏器重量,肝、肾功能均无显著性差异。对40例大鼠11种脏器病理检查均未见药物损伤性病变。 相似文献
14.
Superficial cells of the oral mucosal epithelium in the carp and the cytoskeleton of the epithelial cells are examined by scanning and transmission electron microscopy. Microridges are formed on the surface of the epithelium. Epithelial cells contain two types of vesicles: mucous secretory vesicles and coated vesicles. Most of the mucous vesicles are situated in the center of the cell near the Golgi apparatus. In freeze-fracture replicas, intramembranous particles are abundant in the membranes of the secretory vesicles but rare in the apical plasma membrane. Coated vesicles are situated in the apical and subapical cytoplasm. A great number of thick filaments, considered to be keratin filaments, run randomly throughout the cell to form a meshwork. Thick filaments, which are sparse in the central cytoplasm, are connected to the membranes of the secretory vesicles and other membranous organelles. A layer of closely packed thin filaments, considered to be actin filaments, is found just beneath the apical plasma membrane. Microtubules also occur in the apical cytoplasm and run almost parallel to the cell surface. Both kinds of vesicles are connected to the thin and thick filaments. Their functional significance in the regulation of membrane at the free surface is discussed. 相似文献
15.
Yasuyuki Takeda Makoto Tanaka Hiroyuki Miyazaki Suguru Takeo Kikuo Nomoto Yasunobu Yoshikai 《Cancer immunology, immunotherapy : CII》1994,38(3):143-148
The growth of MethA tumor was significantly inhibited by oral administration of the -glucan SPR-901 in BALB/c (+/+) mice but not in nude mice. Mice treated orally with SPR-901 exhibited an augmentation of antigen-specific resistance against rechallenge with the tumor cells. The tumor-neutralizing activity of regional lymph node cells from MethA-bearing mice against the tumor was augmented by oral administration of SPR-901. The tumor-neutralizing activity of lymph node cells from SPR-901-treated mice mainly appeared in Lyt2+cells. Furthermore, lymphokine-activated killer activity of these cells was enhanced by administration of SPR-901. The antitumor effect of SPR-901 was abrogated in mice depleted of either L3T4+ or Lyt2+ cells, and in cyclosporin-A-treated mice. These results suggest that Lyt2+ cells are important effector cells in MethA-bearing mice orally adminstered SPR-901 and that functional exertion of both Lyt2+ and L3T4+T cells is necessary for the antitumor effect of orally administered SPR-901 in vivo. 相似文献
16.
将编码Vi抗原的基因克隆到减毒的鼠伤寒沙门氏菌中组建的基因重组株Vi4072,以3×10~8CFU一次口服感染Balb/C小鼠,4天后按7,14,21,28,35,42,49,56,63,70天的间隔收集分离小鼠的集合淋巴结,肝,脾.鉴别是否有本菌出现,并检测血清和小肠匀浆液中的vi抗体.结果表明,感染后49天仍可从脾中分离到该菌;70天仍可从血清和小肠匀浆液中测出vi抗体。 相似文献
17.
18.
Pornanong Aramwit Qiuran Jiang Supritha Muppuri Narendra Reddy 《Biotechnology and bioengineering》2023,120(10):2827-2839
Transgenic modification of Bombyx mori silkworms is a benign approach for the production of silk fibers with extraordinary properties and also to generate therapeutic proteins and other biomolecules for various applications. Silk fibers with fluorescence lasting more than a year, natural protein fibers with strength and toughness exceeding that of spider silk, proteins and therapeutic biomolecules with exceptional properties have been developed using transgenic technology. The transgenic modifications have been done primarily by modifying the silk sericin and fibroin genes and also the silk producing glands. Although the genetic modifications were typically performed using the sericin 1 and other genes, newer techniques such as CRISPR/Cas9 have enabled successful modifications of both the fibroin H-chain and L-chain. Such modifications have led to the production of therapeutic proteins and other biomolecules in reasonable quantities at affordable costs for tissue engineering and other medical applications. Transgenically modified silkworms also have distinct and long-lasting fluorescence useful for bioimaging applications. This review presents an overview of the transgenic techniques for modifications of B. mori silkworms and the properties obtained due to such modifications with particular focus on production of growth factors, fluorescent proteins, and high performance protein fibers. 相似文献
19.
S. Chatfield M. Roberts P. Londono I. Cropley G. Douce G. Dougan 《FEMS immunology and medical microbiology》1993,7(1):1-7
Abstract Safe, live attenuated Salmonella strains can be produced by introducing defined non-reverting mutations into the chromosome. Such rationally attenuated strains have proved to be excellent oral vaccines in several animal species and can therefore be considered as candidate vaccines against invasive salmonellosis in both animals and man. A panel of attenuating lesions is now available from which it is possible to tailor the level of attenuation and hence produce strains with different immunogenic properties. Because of the spectrum of immune responses produced by such Salmonella vaccine strains they have been utilised extensively as vectors for delivering heterologous antigens to the mammalian immune system. We have focussed on the development of a single dose oral tetanus vaccine based on attenuated Salmonella strains expressing a non-toxic, immunogenic protein derived from tetanus toxin (fragment C). Several different expression systems have been used for fragment C and candidate vaccine strains have been constructed that are capable of protecting orally immunised mice against a lethal challenge with tetanus toxin. An oral tetanus vaccine may help to reduce the mortality rate from tetanus in the developing world by overcoming the problems associated with the implementation of vaccine programmes using the current parenteral vaccine. 相似文献
20.
随着生物制药的迅速发展,许多酶类药物应运而生,在治疗代谢疾病、心血管疾病、癌症等诸多疾病上发挥着越来越重要的作用。但是酶类药物也存在一些不足,如潜在的免疫原性、较短的体内半衰期,以及较差的组织靶向性,影响了酶类药物的疗效和应用。为克服这些缺点,人们已开发出多种技术,如通过糖基化、聚乙二醇修饰等分子工程技术提升酶蛋白药效,另一方面酶基因疗法也已成功用于多种酶缺陷疾病的治疗。基于酶类药物的迅速发展和广泛的应用前景,本文对酶类药物的现状进行较详细的阐述,并对酶类药物的优势、所存在的问题及未来发展趋势进行分析和评述。 相似文献