We describe a 75-year-old man who had had a lump in his neck for about 15 years. At his first visit to our hospital, poorly differentiated papillary carcinoma of the thyroid was diagnosed by means of ...aspiration cytology; x-rays revealed the presence of lung metastases. He was thyrotoxic with positive thyroid stimulating antibody (TSAb). He was reluctant to undergo surgery. In an early stage of the treatment for Graves' disease, he became hypothyroid with decreased TSAb activity and strongly positive thyroid stimulation blocking antibody (TSBAb), and rapid growth of the thyroid carcinoma with anaplastic transformation was observed. The increase in the size of the transformed thyroid carcinoma was shown to be exponential by ultrasonography. This is a rare case in which anaplastic transformation of the thyroid papillary carcinoma became apparent during treatment of Graves' disease with varied activity of thyrotropin receptor antibodies.
Hard X-ray astronomical observatories in orbit suffer from a significant amount of background due to radioactivation induced by cosmic-ray protons and/or geomagnetically trapped protons. Within the ...framework of a full Monte Carlo simulation, we present modeling of in-orbit instrumental background dominated by radioactivation. To reduce the computation time required by straightforward simulations of delayed emissions from activated isotopes, we insert a semi-analytical calculation that converts production probabilities of radioactive isotopes by interaction of the primary protons into decay rates at measurement time of all secondary isotopes. Therefore, our simulation method is separated into three steps: (1) simulation of isotope production, (2) semi-analytical conversion to decay rates, and (3) simulation of decays of the isotopes at measurement time. This method is verified by a simple setup that has a CdTe semiconductor detector, and shows a 100-fold improvement in efficiency over the straightforward simulation. The simulation framework was tested against data measured with a CdTe sensor in the Hard X-ray Imager onboard the Hitomi X-ray Astronomy Satellite, which was put into a low Earth orbit with an altitude of 570 km and an inclination of 31 degrees, and thus experienced a large amount of irradiation from geomagnetically trapped protons during its passages through the South Atlantic Anomaly. The simulation is able to treat full histories of the proton irradiation and multiple measurement windows. The simulation results agree very well with the measured data, showing that the measured background is well described by the combination of proton-induced radioactivation of the CdTe detector itself and thick Bi4Ge3O12 scintillator shields, leakage of cosmic X-ray background and albedo gamma-ray radiation, and emissions from naturally contaminated isotopes in the detector system.
We report the case of a massive paraesophageal hiatal hernia with gastric volvulus which presented with the symptom of a precordial sense of pressure for over two years, which was successfully ...treated with laparoscopic surgery. The patient is presently in good condition, without any recurrence of either the hiatal hernia or other symptoms one year after surgery. This approach is considered to be a safe and effective procedure, and it also provides for rapid recovery from the operation.
The Soft Gamma-ray Detector (SGD), to be deployed onboard the {\it ASTRO-H} satellite, has been developed to provide the highest sensitivity observations of celestial sources in the energy band of ...60-600~keV by employing a detector concept which uses a Compton camera whose field-of-view is restricted by a BGO shield to a few degree (narrow-FOV Compton camera). In this concept, the background from outside the FOV can be heavily suppressed by constraining the incident direction of the gamma ray reconstructed by the Compton camera to be consistent with the narrow FOV. We, for the first time, demonstrate the validity of the concept using background data taken during the thermal vacuum test and the low-temperature environment test of the flight model of SGD on ground. We show that the measured background level is suppressed to less than 10\% by combining the event rejection using the anti-coincidence trigger of the active BGO shield and by using Compton event reconstruction techniques. More than 75\% of the signals from the field-of-view are retained against the background rejection, which clearly demonstrates the improvement of signal-to-noise ratio. The estimated effective area of 22.8~cm\(^2\) meets the mission requirement even though not all of the operational parameters of the instrument have been fully optimized yet.
Resection of a tumor located in the paracaval portion of the liver, without sacrificing other parts of the liver, is surgically challenging. Here, we describe using a laparoscopic caudal approach for ...a small hepatocellular carcinoma located in the paracaval portion. It is the first case using the laparoscopic caudal approach to be reported in the literature. Compared with the conventional approaches, this procedure can minimize both surgical invasiveness and the volume of liver parenchyma to be resected. In addition, the laparoscopic view is suitable for this procedure. The laparoscopic caudal approach can be a safe procedure with minimal invasiveness for a small paracaval tumor, particularly in patients with liver cirrhosis.
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