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131.
132.
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
133.
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
134.
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
135.
Mori S Endo M Nishizawa K Ohno M Miyazaki H Tsujita K Saito Y 《Physics in medicine and biology》2005,50(22):N359-N370
The prototype cone-beam CT (CBCT) has a larger beam width than the conventional multi-detector row CT (MDCT). This causes a non-uniform angular distribution of the x-ray beam intensity known as the heel effect. Scan conditions for CBCT tube current are adjusted on the anode side to obtain an acceptable clinical image quality. However, as the dose is greater on the cathode side than on the anode side, the signal-to-noise ratio on the cathode side is excessively high, resulting in an unnecessary dose amount. To compensate for the heel effect, we developed a heel effect compensation (HEC) filter. The HEC filter rendered the dose distribution uniform and reduced the dose by an average of 25% for free air and by 20% for CTDI phantoms compared to doses with the conventional filter. In addition, its effect in rendering the effective energy uniform resulted in an improvement in image quality. This new HEC filter may be useful in cone-beam CT studies. 相似文献
136.
In the oxidation of 3.4-dihydroxyphenylalanine (DOPA) the effect of the asymmetrical structure in poly-L -lysine-copper(II) complex (PLL-Cu(II)) on the asymmetrical selectivity ratio was investigated at various reaction temperatures and various preparation conditions of the catalyst, or by addition of catechol or phenylalanine. From the comparison of the asymmetric selectivity with the structure of the catalyst, the combination of two or more asymmetric cupric complex units was considered as the cause for the asymmetrically selective catalysis, where α-helical structure may serve to hold the two or more cupric complex units in a special steric configuration. Moreover a plausible mechanism for the asymmetrically selective oxidation was discussed by the evidence from the addition effects of catechol or phenylalanine and by the asymmetrically selective interaction between PLL-Cu(II) and DOPA. Then, the mechanism seems to be confirmed by an inspection with a molecular model. 相似文献
137.
The mesophase induced circular dichroism (CD) of biphenyl and its derivatives was investigated using the Tween 80 (monooleate of the ether of sorbitan with 4 mol of polyethyleneglycol)-water system, which can form a twisted smectic mesophase. The sign of CD bands in this mesophase is explained by a modified C2-symmetry rule, since it can be considered that alignment of the solute molecules in this mesophase can be elucidated in terms of a pseudo-C2 symmetry, when the concentration of the solute is comparatively high. The assignments of the electronic transitions of the solute molecules show a good accordance with results of magnetic circular dichroism study. 相似文献
138.
Yamaguchi K Nagano M Torada N Hamasaki N Kawakita M Tanaka M 《Rinsho byori. The Japanese journal of clinical pathology》2004,52(4):336-339
A novel urine tumor marker, diacetylspermine, was compared with two conventional serum tumor markers, carcinoembryonic antigen (CEA) (highly specific for pancreatic cancer) and carbohydrate antigen (CA) 19-9 (highly sensitive for pancreatic cancer), in 125 patients with bilio-pancreatic tumors. When the diagnoses of benign or malignant conditions were examined, the sensitivity of urine diacetylspermine (75%) was shown to be higher than that of CEA (44%; P = 0.044) and CA19-9 (75%). The specificity of urine diacetylspermine (81%) was lower than that of CEA (92%) and as high as that of CA19-9 (80%). These results suggest that urine discetylspermine is a highly sensitive and specific novel marker for bilio-pancreatic carcinoma. 相似文献
139.
Kiyoshi Tanikawa Takamichi Enomoto Masahiro Hatano Keiko Motegi Zenjiro Okuno 《Macromolecular chemistry and physics.》1975,176(10):3025-3034
Poly(N-vinylcarbazole), (PNVC), was prepared, fractionated by gel permeation chromatography, and then characterized by viscometry and vapour pressure osmometry. The fractionated PNVC species with relatively narrow molecular weight distributions were successfully used to measure both their electrical dark-conductivity and photoconductivity using a surface type cell in high vacuum (ca. 10?7 mm Hg) at room temperature. A molecular weight dependent photoconductivity was found for the fractionated PNVCs with weight average molecular weights in the range of 1,2·103 to 2,4·105. This observation is in contradiction to Epping's results who has found a molecular weight independent photoconductivity in the molecular weight range of 3·105 to 7·106. Our molecular weight dependence may be well understood in terms of the interrupted overlap of the π-electrons of adjacent carbazolyl groups at the terminal parts of the polymer chains, this effect being all the more stronger the smaller the molecular weight is. 相似文献
140.
Favorable efficacy of long-term lamivudine therapy in patients with chronic hepatitis B: an 8-year follow-up study 总被引:7,自引:0,他引:7
Akuta N Suzuki F Suzuki Y Sezaki H Hosaka T Someya T Kobayashi M Saitoh S Arase Y Ikeda K Kobayashi M Kumada H 《Journal of medical virology》2005,75(4):491-498
The long-term efficacy of lamivudine therapy in patients with hepatitis B virus (HBV) infection is still not clear. In this study, 20 non-cirrhotic Japanese patients infected with HBV received lamivudine therapy for more than 1 year and were followed for a median period of 8.5 years (range, 6.7-8.7 years). The rates of HBe antigen (HbeAg) negative, HBV-DNA undetectable, and alanine aminotransferase (ALT) normal level at the start of lamivudine were 55%, 25%, and 20% and 85%, 80%, and were 80%, respectively, at the last visit, including patients who received additional treatment. The values at the last visit tended to and were significantly higher than those at the start. The values improved at the last visit regardless of the emergence of YMDD motif mutant and continuation of lamivudine. YMDD mutant and biochemical relapse with mutant virus (breakthrough hepatitis) appeared in 65% and 45% during follow-up, respectively, but severe breakthrough hepatitis occurred in only 5%. Furthermore, 80% of patients who received additional treatment for breakthrough hepatitis, regardless of continuation of lamivudine, were ALT normal level at the last visit, in contrast to 25% untreated. HBsAg clearance occurred in two patients of the discontinuous lamivudine group with non-vertical transmission, who were relatively young. One was infected with HBV genotype C with breakthrough hepatitis and the other had no YMDD mutant and was infected with genotype D, a rare type in Japan. None developed cirrhosis or hepatocellular carcinoma (HCC) during follow-up. Our results suggest that long-term lamivudine therapy improves long-term prognosis, especially when additional treatment for breakthrough hepatitis is used. 相似文献