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101.
Masao Yoshikawa Hiroiyuki Nomori Masahiro Hatano 《Macromolecular chemistry and physics.》1978,179(10):2397-2405
Circular dichroism (CD) and ultraviolet absorption (UV) spectra were measured for poly{γ-[2-(9-carbazolyl)ethyl] L -glutamate} (PCLG), whose side chain chromophore has three π – π* transitions in a wavelength region not overlapping with the n – π* transition of the main chain peptide group. For the dilute solution in any given helicogenic solvent, the observed CD sign had a good correlation to the polarization direction of the π – π* transitions. On the other hand, a concentrated solution with a concentration of ca. 15 wt.-% was found to form a liquid crystalline phase, which was probably nematic at room temperature. The CD spectral profiles of the cast film of the polypeptide were quite different from that of the dilute solution. Origins of the optical activity are discussed. 相似文献
102.
103.
Masahiro Yamasaki 《Developmental dynamics》1990,188(3):249-259
The thyroid and thymic arteries were investigated in 50 male and 50 female rats. In more than 70% of the animals, on both sides the cranial thyroid artery forms a common trunk with the ascending pharyngeal artery. The caudal thyroid artery arises not from the deep cervical but from the pericardiacophrenic artery. It may be replaced, however, by a branch of some other artery, such as the brachiocephalic, subclavian, vertebral, or ascending cervical, suggesting a shift of its origin from the internal thoracic artery to the thyrocervical trunk as in man. All the thoracic lobes of the thymus are supplied directly by a thymic branch of the internal thoracic artery or indirectly by a branch of the pericardiacophrenic artery. More than half of the specimens have a cervical thymic lobe of variable size, which is supplied by a branch of the cranial thyroid, external carotid, and/or occipital arteries. Some of these thymic arteries, except those from the external carotid and occipital arteries, reach the thoracic lobe. The thoracic lobes lacking a cervical lobe may be supplied by the thymic branch arising only from the cranial thyroid artery. Other anomalous arteries supplying the thoracic lobe are derived from the superficial cervical and/or the right common carotid arteries. These results show that the thymic arteries of rats are basically similar to those of man, although they display a clear difference in their frequency and origin. 相似文献
104.
105.
Kawada K Yonei T Ueoka H Kiura K Tabata M Takigawa N Harada M Tanimoto M 《Acta medica Okayama》2002,56(3):129-134
When the development of chemotherapeutic agents reaches the clinical trial stage, it is necessary to perform drug sensitivity tests quickly in order to select the most promising agents for the treatment of cancer. In order to assess the possibility of using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay as a substitute for the human tumor clonogenic assay (HTCA), we evaluated the correlation between the results obtained by these 2 assays in 5 human lung cancer cell lines. The correlation coefficient between the results of the HTCA and the MTT assay was 0.673, indicating a relatively good correlation. The correlation was most prominent in platinum analogues (r = 0.939) and good in anthracyclines/anthracenedione (r = 0.611). However, no significant correlation was observed in vinca alkaloids, etoposide, irinotecan, SN-38 (an active metabolite of irinotecan), and rhizoxin. The results of the MTT assay showed a high degree of correlation with those of the HTCA in predicting the sensitivity of cancer cell lines to platinum analogues, and anthracyclines/anthracenedione. These results suggest that the MTT assay may be more convenient and quickly performed than the HTCA and can replace HTCA in evaluating the effects of anticancer agents, especially the platinum analogues and anthracyclines/anthracenedione. 相似文献
106.
107.
Satoru Honma Akinari Tokiyoshi Katsushi Kawai Masahiro Koizumi Kodo Kodama 《Anatomical science international / Japanese Association of Anatomists》2008,83(4):232-238
A radial artery running beneath the biceps tendon was found in the cadaver of a Japanese woman during a student dissection
course at Kumamoto University School of Medicine in 2006. The brachial artery bifurcated into the radial artery and the ulnar
artery in the cubital fossa, and the radial artery twisted laterally running beneath the biceps tendon, and when it was situated
laterally to the tendon, twisted distally at the level of the radial tuberosity, and then twisted medially again. After the
radial artery passed over the biceps tendon, it turned distally and continued as a normal radial artery. The superficial brachial
artery, which coexisted with the brachial artery, was given off from the axillary artery and it continued to the final twist
of the radial artery. The course of this radial artery is similar to the arterial rings surrounding the biceps tendon, found
during the same dissection course. The arterial rings were formed between the brachial artery and the radial artery, and their
proximal origins ran beneath the biceps tendon, while the distal origins were superficial. The present arterial variation
is thought to have occurred when the normal part of the radial artery in the cubital fossa was substituted by the arterial
ring, coexisting with the superficial brachial artery, which usually disappears during normal development. Furthermore, it
is suggested that a part of the arterial ring always remains as a radial recurrent artery. 相似文献
108.
Katsushi Kawai Kazuya Yoshinaga Masahiro Koizumi Satoru Honma Akinari Tokiyoshi Kodo Kodama 《Annals of anatomy》2006,188(1):33-38
A middle meningeal artery arising from the internal carotid artery was found in the right half of the head of an 85-year-old male cadaver during student dissection practice. It arose from the lateral aspect of the internal carotid artery in the carotid canal, arrived at the foramen lacerum after running forward. It then ran backward under the trigeminal ganglion and took the usual course after passing its posterior margin. On one hand, the maxillary artery did not issue the middle meningeal artery, gave off only a small twig supplying the lateral pterygoid muscle at the corresponding position. It was corroborated by the fact that the foramen spinosum was absent in this example. During usual development, the middle meningeal artery primarily springs from the supraorbital branch of the stapedial artery that arises from the dorsal part of the second branchial artery. Later, by the formation of the external carotid artery connecting with the common trunk of the infraorbital and mandibular branches (maxillomandibular division) of the stapedial artery and by the atrophy of the proximal part of it, the middle meningeal artery is finally supplied by the external carotid artery. But in this example, it is supposed that the middle meningeal artery arose from a more distal position of the internal carotid artery owing to the persistence of the anastomosis between the dorsal part of the first branchial artery and the supraorbital branch and the interruption of the connection between the supraorbital branch and maxillomandibular division of the stapedial artery. 相似文献
109.
Generation of peroxynitrite and apoptosis in placenta of patients with chorioamnionitis: possible implications in placental abruption 总被引:3,自引:0,他引:3
Nakatsuka M Asagiri K Kimura Y Kamada Y Tada K Kudo T 《Human reproduction (Oxford, England)》1999,14(4):1101-1106
The reaction of nitric oxide (NO) and superoxide results in the formation of peroxynitrite, a potent and relatively long-lived oxidant. In infectious diseases, these molecules are not only bactericidal but also toxic to host cells. Chorioamnionitis is often complicated by premature rupture of membranes and can be associated with placental abruption. These diseases are significant causes of premature low-birth-weight deliveries and consequently the morbidity and mortality of neonates. Lipopolysaccharide, bacterial endotoxin, is known to be elevated in the amniotic fluid of patients with chorioamnionitis. Lipopolysaccharide is known to induce the formation of NO and superoxide. We report here that nitrite/nitrate, stable metabolites of NO, were increased in serum from patients with chorioamnionitis. Immunohistochemical studies demonstrated enhanced expression of inducible NO synthase and formation of nitrotyrosine, a footprint of peroxynitrite, in the placentae from patients with chorioamnionitis and also in patients with placental abruption. Furthermore, apoptotic cell death was also increased in the placentae from patients with both diseases. These results suggest that chorioamnionitis and a portion of placental abruption may share a common cascade of placental injury. Nitric oxide and its metabolities may play an important role in this cascade. 相似文献
110.
Masahiro Yamashita Anat Achiron Tomoyuki Miura Jun Takehisa Eiji Ido Tatsuhiko Igarashi Kentaro Ibuki Mitsuhiro Osame Shunro Sonoda Eldad Melamed Prof. Masanori Hayami Batya Shohat 《Virus genes》1995,10(1):85-90
A new endemic focus of human T-lymphotropic virus type I (HTL V-I) was recently reported among Mashhadi Jews, a group of immigrants from northeastern Iran to Israel. We extracted DNAs from fresh peripheral blood mononuclear cells (PBMCs) and/or gargle mouthwash from 10 HTL V-I carriers, who consisted of members of one family, and HTL V-I-associated myelopathy (HAM) and adult T-cell leukemia (ATL) patients. Long terminal repeat (LTR) regions of proviral DNAs were sequenced and analyzed phylogenetically. In a phylogenetic tree, all the Mashhadi HTL V-I isolates belonged to subtype A, one of the three subtypes of the cosmopolitan type of HTL V-I, and made a tight cluster distinct from the other isolates of subtype A from Japan, India, the Caribbean Basin, and South America. Although a few nucleotide substitutions were observed among the clones sequenced, no characteristic sequence variation was found in different disease manifestations, even in one family or different sources of DNA preparation. 相似文献