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1.
Adherence of streptococci to surface-modified glass 总被引:2,自引:0,他引:2
Four types of surface-modified glass were prepared. Aminopropyl glass was prepared by alkylsilylation of glass slides with gamma-aminopropyltriethoxysilane. This glass carries primary amino groups which may be protonated at pH 7.2. Owing to the presence of both positively charged ions and hydrophobic ethoxyl groups, the glass is considered to be amphipathic. Three other types of surface-modified glass slides were prepared from aminopropyl glass by forming Schiff's bases with three aldehydes: glucose, glyoxylic acid and hexanal. The aldehyde-treated slides were subsequently reduced using sodium borohydride. Thus, the surface of the glass was rendered hydrophilic, ampholytic or hydrophobic, respectively. The adherence of two Streptococcus sanguis strains and two Streptococcus mutans strains to the surface-modified glass slides was studied. Different strains showed differences in adherence to these slides depending on their physico-chemical surface properties. For S. sanguis ATCC 10556, hydrophobic bonds seemed to be most important, while in S. mutans OMZ 176, ionic interactions made the highest contribution to adhesion. Hydrogen bonds seemed to contribute least to adherence. 相似文献
2.
T Ishizuka J Yoshitake T Yamada S Horie M Koshiishi S Nagai T Satou 《Acta cytologica》1988,32(5):658-662
Cytologic examination of sputum samples from an elderly patient revealed the presence of two cell populations: squamous cell carcinoma cells and rhabdomyosarcoma cells. The abnormal squamous cells showed both keratinizing and nonkeratinizing forms while some of the rhabdomyosarcoma cells showed cross striations. Sputum cytology was thus able to suggest a diagnosis of pulmonary carcinosarcoma. Histologically, the tumor was composed mainly of sarcomatous tissue showing various kinds of cells: fusiform or fibrous cells, round anaplastic cells, spindled cells with typical cross striations and myoblastic cells. A partially myxomatous degeneration was present. In addition, squamous cell carcinoma proliferated along the bronchi and formed small invasive cell nests in the sarcomatous tissue. No transition between the two components was noted. Both cellular constituents had metastasized to an interlobar lymph node. 相似文献
3.
Satou K.; Furuichi E.; Takiguchi K.; Takagi T.; Kuhara S. 《Bioinformatics (Oxford, England)》1993,9(3):259-265
We have developed a deductive database system PACADE for analyzing3-D and secondary structures of protein. The PA CADE systemconsists of a relational database created from Protein DataBank and a deductive engine DEE based on logic programming.It has the following features: (1) The system has an inferencemechanism. This means by which users can easily write and checkbiological hypotheses using logical and declarative rules insteadof procedural programs. (2) The relational database of the PACADE system stores data on bath 3-D and secondwy structuresof protein. The integration of this two level structure makesfeasible an abstract representation of the protein structure.We describe herein the design, functions, and implementationof this PACADE system. 相似文献
4.
Role of salicylic acid glucosyltransferase in balancing growth and defence for optimum plant fitness
5.
Yasuhiro Iwao Chihiro Kimoto Ayaka Fujimoto Asuka Suda Yuki Hara 《Molecular reproduction and development》2020,87(3):358-369
The union between a sperm and an egg nucleus in egg fertilization is necessary to mix genetic materials to create a new diploid genome for the next generation. In most animals, only one sperm is incorporated into the egg (monospermy), but several animals exhibit physiological polyspermy in which several sperms enter the egg during normal fertilization. However, only one sperm nucleus forms the zygote nucleus with the egg nucleus, even in a polyspermic egg. The cellular and molecular mechanisms involved in the selection of sperm nuclei in the egg cytoplasm have been well investigated in urodele amphibians. The principal sperm nucleus develops a larger sperm aster and contacts the egg nucleus to form a zygote nucleus, whereas other accessory sperm nuclei are unable to approach the egg nucleus. The diploid zygote nucleus induces cleavage and participates in embryonic development, whereas the accessory sperm nuclei undergo pyknosis and degenerate. We propose several models to account for the mechanisms of the selection of one sperm nucleus and the degeneration of accessory sperm nuclei. The roles of physiological polyspermy in animal reproduction are discussed by comparison with other polyspermic species. 相似文献
6.
Kazuki Yuzuriha Ayaka Yoshida Shunyi Li Akihiro Kishimura Takeshi Mori Yoshiki Katayama 《Journal of peptide science》2020,26(10)
In this report, we designed conjugates of an antigen peptide with the immunosuppressive vitamins all‐trans retinoic acid (ATRA) and vitamin D3 for efficient induction of antigen‐specific immunotolerance. We established a synthetic scheme for the preparation of the peptide‐vitamin conjugates, which the chemically unstable vitamins tolerated. Among the obtained conjugates, the ATRA conjugate successfully suppressed inflammatory effects in macrophages and dendritic cells and induced antigen presentation in dendritic cells. This synthetic method of conjugate is conceivably applicable to other antigen peptides for induction of antigen‐specific immunotolerance. 相似文献
7.
Wagatsuma Tadao Tanaka Kazuhiro Iino Yuuichirou Satou Tsuyoshi Khan Md. Shahadat Hossain Tawaraya Keitaro 《Plant and Soil》2021,459(1-2):289-313
Plant and Soil - The major factors controlling the soil methane (CH4) concentration and CH4 emissions of various plant (mainly wetland) species were identified. Five plant species (Oryza sativa,... 相似文献
8.
9.
Nakano Ryohei Morita Taiki Okamoto Yuta Fujiwara Ayaka Yamanaka Takehiko Adachi-Hagimori Tetsuya 《BioControl》2021,66(3):407-418
BioControl - Nesidiocoris tenuis (Reuter) (Hemiptera: Miridae) is a zoophytophagous predator that feeds on plants as well as prey. Several non-crop host plant species have been used to maintain... 相似文献
10.