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S Yoshioka

Publications and source records attributed to S Yoshioka.

339 records · Page 19Linked to original sources
PubMed1965

[What Dr. Kure did].

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Hospitals, Psychiatric↗
PubMedDate not supplied

Ovulation: a multi-gene, multi-step process.

The luteinizing hormone (LH) surge initiates a cascade of proteolytic events that control ovulation. One of the genes induced by LH is the progesterone receptor (PR). Because mice with a mutant PR gene (PRKO) fail to ovulate and are infertile, we have used them as a model in which to determine PR target genes that might mediate the ovulatory process. The matrix metalloproteinases (MMPs: MMP2, MMP9, and MMP13) appear to be expressed in ovaries of PRKO mice in a manner similar to that in their wild-type littermates. However, the expression of two other types of proteases, cathepsin L (a member of the papain family) and ADAMTS-1 (A Disintegrin And Metalloproteinase with Thrombospondin-like motifs), are selectively induced in granulosa cells of preovulatory follicles by the LH surge. Maximal levels of these proteases are observed at 12-16 h after an LH surge, the time of ovulation. Furthermore, mRNAs encoding cathepsin L and ADAMTS-1 are reduced in the PRKO mice compared to their wild-type littermates. These novel observations indicate that these two proteases regulate some key step(s) controlling ovulation.

ADAM Proteins↗
PubMedDate not supplied

Thrombocytopenia with absent radii syndrome: studies on serum thrombopoietin levels and megakaryopoiesis in vitro.

PURPOSE: The pathogenesis of thrombocytopenia in patients with thrombocytopenia with absent radii (TAR) syndrome has not been clarified yet. PATIENTS AND METHODS: This is the first report of a Japanese patient with TAR syndrome. We studied his megakaryopoiesis in vitro and serum levels of thrombopoietin (TPO). RESULTS: Serum levels of TPO in the patient with TAR syndrome were comparable with those of an age-matched control. The bone marrow cells from the patient with TAR syndrome actually generated megakaryocyte colonies in the presence of TPO and the numbers were significantly greater than those from the age-matched control marrow. However, megakaryocyte colonies from the marrow cells with TAR syndrome contained a much lower number of cells per colony and the size of the individual megakaryocytes appeared to be smaller. CONCLUSION: These data suggest that megakaryocyte progenitors from patients with TAR syndrome may have decreased proliferative and differentiative capacity to respond to TPO, leading to thrombocytopenia.

Hematopoiesis↗
PubMedDate not supplied

Digital TV tomography: description and physical assessment.

A digital TV tomography system, capable of retrospective reconstruction of multiple digital tomographic images, has been developed and its basic physical characteristics have been evaluated. The multiple tomographic images were formed through retrospective reconstruction of digital data acquired on a linear tomographic x-ray unit and an image intensifier-television system. Digital data were obtained with a series of 30 pulsed exposures during linear motion of the system. A distortion correction algorithm for the convex surface of the image intensifier was developed in order to reduce image distortion. A phantom study showed that the square-wave response at the fulcrum plane was slightly inferior to that in conventional tomography. There was also a slight decrease in the square-wave response away from the fulcrum plane and upon application of a correction algorithm, as compared with the response of the original reconstructed image at the fulcrum plane. The exposure dose for a single image was approximately half that in conventional tomography. Because of many advantages, including low exposure, short examination time, digital image manipulation, and applicability to picture archiving and communication systems, this is likely to become an important method in radiology when further technical refinements have been made.

Angiography, Digital Subtraction↗
PubMedDate not supplied

Clinical evaluation of digital TV tomography.

A unit for digital TV tomography (DTT) was constructed on the basis of retrospective reconstruction of digital data acquired during a linear tomographic motion of an X-ray tube and an image intensifier with a television camera (I.I.-TV) assembly. Following descriptions of the basic principle and system, clinical results obtained with this unit are presented. Comparison with conventional tomography of the chest, skull, abdomen, and bones and joints showed equal diagnostic information in more than 50% of cases. Application to intra-arterial and intravenous DSA provided excellent images, but no new information was obtained. DTT has the advantages of technical simplicity, short examination time, low exposure dose, and compatibility with a PACS system. This technique will become an important part of a modern radiology department.

Aged↗
PubMedDate not supplied

A successful treatment for hepatocellular carcinoma with atrial tumor thrombus.

A 66-year-old man with an advanced hepatocellular carcinoma and tumor thrombus extending into the right atrium was treated by transcatheter arterial infusion of lipiodol and aclarubicin. This brought about a remarkable reduction of the tumor and the disappearance of the right atrial tumor thrombus. The tumor was then radically resected by hepatic posterior segmentectomy with combined resection of the right hepatic vein, where the tumor thrombus remained. He is doing well without any signs of recurrence 22 months after the operation.

Aclarubicin↗