George Matsumura

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The process of fusion of the ossification centres in the occipital squama is described in human fetal skulls. During the 3rd fetal month, irregular ossification centres appear in the membranous tissue behind the cartilaginous supraoccipital bone plate. The centres rapidly develop to form a meshwork of bony trabeculae which cover the external surface of the(More)
Foramen Vesalius is known to be an inconstant foramen, which appears in the anteriomedial side of the foramen ovale. The foramen Vesalius is classified into the open type and the closed type. We studied the frequencies and the types of foramen Vesalius in Japanese by examining 20 juvenile skulls from 3 months to 8 years old and 400 adult skulls from 18 to(More)
The development of ossification centres in the membranous occipital squama is described, based on observations on human fetal skulls. The interparietal part develops basically from 3 pairs, 1 primary pair and 2 secondary pairs; an additional 4th pair is occasionally observed. The so-called separated interparietal bones (Inca bones) are formed by a failure(More)
Skeletal muscles consist of slow-twitch and fast-twitch muscle fibers, which have distinct physiological and biochemical properties. The muscle fiber composition determines the contractile velocity and fatigability of a particular skeletal muscle. We analyzed the systemic distribution of slow muscle fibers in all rodent skeletal muscles by myosin ATPase(More)
Sufficient improvement in De Quervain disease, is not always archieved even by tenosynovectomy, and the reason for this appears to be anatomical variation in the first extensor compartment of the hand. In this study we examined the first extensor compartment of 159 hands of 80 human cadavers. Hiranuma and colleagues documented four anatomical types of first(More)
The distribution of the high-affinity choline transporter (CHT) was determined in the human and macaque monkey spinal cord using in situ hybridization histochemistry and immunohistochemistry. Signals for CHT mRNA were observed in somatic motor neurons, sympathetic preganglionic neurons, and neurons in the medial part of lamina VII. The mRNA for CHT was(More)
Haemopoietic cells in yolk sac and liver of mouse embryo were examined by light and electron microscopy with particular reference to nuclear and nucleolar structure. Mitotic index of yolk sac haemopoietic cells increased from 10 days of gestation, showing a peak at 11 days and, at 12 days, the lumen of the yolk sac vessels were full of erythroblasts with(More)
The effects of pregnancy on erythropoiesis in the splenic red pulp of the mouse was examined quantitatively by electron microscopy. In the red pulp of a normal female at 60 days of age, erythroid cells were most numerous, constituting 73.3% of all the hemopoietic cells, and 55.1% of the erythroids were erythroblasts. By quantitative stereology,(More)
In this study, we examined the position of intercrestal line that is called Jacoby's line at heights of the vertebral body and spinous process in different positions of the lumbar spine using radiographs of 100 subjects. At the height of the spinous process, Jacoby's line was most often observed in the extension position in L4 spinous process middle 1/3(More)