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991.
Yokoyama Fumiaki Kawamoto Jun Imai Tomoya Kurihara Tatsuo 《Extremophiles : life under extreme conditions》2017,21(4):723-731
Extremophiles - A cold-adapted bacterium, Shewanella livingstonensis Ac10, which produces eicosapentaenoic acid (EPA) as a component of its membrane phospholipids, is useful as a model to study the... 相似文献
992.
Fumiaki Tabuchi Aroonlug Lulitanond Viraphong Lulitanond Sudaluck Thunyaharn Chikara Kaito 《Microbiology and immunology》2020,64(3):219-225
In this present study, we investigated the phenol-soluble modulin (psm-mec) mutations, the staphylococcal cassette chromosome mec (SCCmec) types, and toxin production in 102 methicillin-resistant Staphylococcus aureus (MRSA) isolates from the northeast and central regions of Thailand. The MRSA isolates carrying -7T>C psm-mec in Type II SCCmec (n = 18) and the MRSA isolates carrying no psm-mec in Type IV (n = 8) or Type IX SCCmec (n = 4) had higher hemolytic activity against sheep erythrocytes than MRSA isolates carrying intact psm-mec in Type III SCCmec (n = 34), but MRSA isolates carrying no psm-mec in Type I SCCmec (n = 27) did not. 相似文献
993.
994.
Fumiaki Nakatsubo Ian D. Reid T.Kent Kirk 《Biochimica et Biophysica Acta (BBA)/General Subjects》1982,719(2):284-291
The metabolism of a lignin substructure model compound, 1,2-bis(3-methoxy-4-ethoxyphenyl)propane-1,3-diol (Ia) in ligninolytic cultures of Phanerochaete chrysosporium was studied to help elucidate the biochemical mechanism of lignin degradation. The primary reaction was cleavage of the model compound between C1 and C2 of the propane moiety to produce 1-(3-methoxy-4-ethoxyphenyl)ethane-1,2-diol and a C6-C1 product (probably 3-methoxy-4-ethoxybenzaldehyde). Other identified products arose secondarily; all were further metabolized. Even though the model compound was a mixture of four stereoisomers, no stereoselectivity was observed in its metabolism. In cultures under 18O2, the initial cleavage produced the diol product with ≈70% enrichment by 18O in the benzyl alcohol group. The diol was a mixture of the two possible enantiomers, and the O2-derived hydroxyl was incorporated at the asymmetric (benzyl) carbon. (Limited optical activity in the diol was traced to selective further metabolism of the D form.) These results show that the primary cleavage reaction lacked stereospecificity and was primarily oxygenative, implicating a nonspecific oxygenase or a nonenzymatic reaction involving activated oxygen. Preliminary experiments demonstrated no cell homogenate activity against Ia. 相似文献
995.
996.
Bone abnormalities in latent TGF-[beta] binding protein (Ltbp)-3-null mice indicate a role for Ltbp-3 in modulating TGF-[beta] bioavailability. 下载免费PDF全文
Branka Dabovic Yan Chen Cristina Colarossi Hiroto Obata Laura Zambuto Mary Ann Perle Daniel B Rifkin 《The Journal of cell biology》2002,156(2):227-232
The TGF-betas are multifunctional proteins whose activities are believed to be controlled by interaction with the latent TGF-beta binding proteins (LTBPs). In spite of substantial effort, the precise in vivo significance of this interaction remains unknown. To examine the role of the Ltbp-3, we made an Ltbp-3-null mutation in the mouse by gene targeting. Homozygous mutant animals develop cranio-facial malformations by day 10. At 2 mo, there is a pronounced rounding of the cranial vault, extension of the mandible beyond the maxilla, and kyphosis. Histological examination of the skulls from null animals revealed ossification of the synchondroses within 2 wk of birth, in contrast to the wild-type synchondroses, which never ossify. Between 6 and 9 mo of age, mutant animals also develop osteosclerosis and osteoarthritis. The pathological changes of the Ltbp-3-null mice are consistent with perturbed TGF-beta signaling in the skull and long bones. These observations give support to the notion that LTBP-3 is important for the control of TGF-beta action. Moreover, the results provide the first in vivo indication for a role of LTBP in modulating TGF-beta bioavailability. 相似文献
997.
Shohko Obata 《BioControl》1986,31(3):303-311
The mechanism of prey finding in adultHarmonia axyridis was investigated by presenting beetles with small gauze or polyethylene bags containing either aphidinfested leaves or healthy
leaves alone together with empty control bags. Beetles were attracted to bags by olfactory and visual cues suggesting the
presence of aphids, including the odor of aphid-infested leaves, the odor of aphids, the odor of healthy leaves, and the sight
of leaves. Particularly effective in prolonging beetles's stay on bags visited was the odor of aphid-infested leaves. It is
suggested that adults ofH. axyridis use olfactory and visual cues to detect prey before actual contact occurs. Use of such cues seems more advantageous than
random searching, as has been reported in many previous studies of coccinellid foraging.
Résumé Le mécanisme de découverte de la proie chez l'adulte d'Harmonia axyridis est étudié en donnant aux Coccinelles de petits sacs en gaze ou en polyéthylène contenant soit des feuilles infestées de pucerons, soit des feuilles saines seules, avec des sacs vides comme témoins. Les coccinelles sont attirées vers les sacs par des indicateurs olfactifs ou visuels suggérant la présence de pucerons, incluant l'odeur des feuilles infestées de pucerons, l'odeur des pucerons, l'odeur des feuilles saines et la vue des feuilles. L'odeur des feuilles infestées de pucerons est particulièrement efficace en prolongeant le séjour des Coccinelles sur le sac visité. Il est suggéré que les adultes d'H. axyridis utilisent des indicateurs olfactifs et visuels pour détecter leur proie avant que s'établisse le véritable contact. L'emploi de tels indicateurs semble plus avantageux que la recherche au hasard, comme cela a été indiqué dans de nombreuses études antérieures sur la quête alimentaire des Coccinelles.相似文献
998.
Kunio Takeyasu Shuji Uchida Yutaka Noguchi Norihisa Fujita Kihachi Saito Fumiaki Hata Hiroshi Yoshida 《Life sciences》1979,25(7):585-592
Chronic blockade of cholinergic transmission with atropine resulted in a decrease in atropine-induced activity in the rats, whereas apomorphine - induced locomotion was enhanced. Maximal binding of 3H-quinuclidinyl benzilate (QNB), a muscarinic antagonist, to homogenate of cerebral cortex, striatum and hippocampus was significantly higher in chronic atropine-treated rats than in control animals. No difference was observed in KD value of the specific 3H-QNB binding or in ID50 value of oxotremorine in inhibiting 3H-QNB binding. No change in the specific binding of 3H-spiroperidol, a dopaminergic antagonist, was observed in those three regions of brains of chronic atropine-treated rats when it was compared with that of control animals. The role of brain muscarinic acetylcholine receptors in behavioral responses is discussed relating an effect of dopaminergic neurons on cholinergic activities. 相似文献
999.
Keiji Terao Koji Fujimoto Fumiaki Cho Shigeo Honjo 《American journal of primatology》1986,11(3):245-251
The mode of inheritance of four different red cell antigens (Ecy, Fcy, Gcy, and Hcy), detected by alloimmune reagents prepared by us for the cynomolgus monkey, was studied. The results of the segregation analysis suggest that each antigen is inherited in an autosomal dominant manner. Both the random sample analysis and family study revealed that two of these red cell antigens (Ecy and Fcy) probably represent the products of two independent genes while the expression of the other two antigens (Gcy and Hcy is governed by two autosomal codominant alleles. Thus, three simian-type blood group systems could be demonstrated by the four newly developed alloimmune reagents. We use the following nomenclature for these blood groups: the E and F blood groups, each with two phenotypes, antigen positive (E and F) and antigen negative (e and f), and the GH blood group having three phenotypes (G, H, and GH). 相似文献
1000.