239 research outputs found
Brain tumors induced in rats by human adenovirus type 12
Oncogenesis of human adenovirus type 12 in the brain
of rats was examined. Newborn rats of Sprague-Dawley and Donryu strains were injected intracranially with human adenovirus type 12. The incidence of intracranial tumors was 91% (30/33) in SpragueDawley and 56% (14/25) in Donryu rats. Except for one tumor nodule located in the parietal cortex of a Sprague.Dawley rat, all tumors developed in the paraventricular areas or in the meninges. Tumors
were quite similar histologically to those induced in hamsters and mice resembling the undifferentiated human brain tumors such as medulloblastoma, ependymoblastoma and embryonic gliomas. From the histological features and primary sites of tumor development, it is suggested that the tumors in the brain of rats induced by adenovirus
type 12 originate from the embryonic cells in the paraventricular area and also from the undifferentiated supporting cells of the peripheral nerves in the leptomeninges.</p
Improvement of spontaneous locomotor activity with JAK inhibition by JTE-052 in rat adjuvant-induced arthritis
Intestinal Perforation by Ingested Foreign Bodies
Seven cases with intestinal perforation by ingested foreign bodies (IFBs) were surgically treated in our hospital between January 2000 and August 2009. We reviewed the preoperative mental conditions, awareness of ingestion, preoperative diagnosis, the type of foreign bodies, perforation site, treatment and morbidity for these patients. The ratio of males to females was 4 : 3, and patient age ranged from 27 years to 85 years. Three of 7 patients had an abnormal mental condition, including neurosis with medication in 1, severe mental retardation in 1 and dementia in 1. Six patients were not aware they had IFBs. Preoperative diagnoses were perforative peritonitis in 6 cases and ileus in 1 case. The ingested objects consisted of fish bones in 4 cases, toothpicks in 2 cases and a press-through package in 1 case. Computed tomography (CT) showed the ingested fish bones in all 4 cases, while plain abdominal radiography demonstrated fish bone in only one of these cases. Toothpicks and a press-through package were not detected on CT or by plain abdominal radiography. The perforation sites were the small intestine in 5 cases and the large intestine (transverse colon) in 2 cases. Treatments were intestinal resection with or without omentectomy in 5 cases, suture alone in 1 case and omentectomy alone in 1 case. Postoperative complications were seen in 2 patients, including hepatic failure and bleeding from gastroesophageal reflux disease in 1 case, and removal and reinsertion of a V-P shunt tube in 1 case. The mortality rate was 0%
Magnetostriction studies up to megagauss fields using fiber Bragg grating technique
We here report magnetostriction measurements under pulsed megagauss fields
using a high-speed 100 MHz strain monitoring system devised using fiber Bragg
grating (FBG) technique with optical filter method. The optical filter method
is a detection scheme of the strain of FBG, where the changing Bragg wavelength
of the FBG reflection is converted to the intensity of reflected light to
enable the 100 MHz measurement. In order to show the usefulness and reliability
of the method, we report the measurements for solid oxygen, spin-controlled
crystal, and volborthite, a deformed Kagom\'{e} quantum spin lattice, using
static magnetic fields up to 7 T and non-destructive millisecond pulse magnets
up to 50 T. Then, we show the application of the method for the
magnetostriction measurements of CaVO, a two-dimensional
antiferromagnet with spin-halves, and LaCoO, an anomalous spin-crossover
oxide, in the megagauss fields.Comment: 9pages, 6 figures, Conference proceedings for MegaGauss16 at Kashiwa,
Japan in Sept. 201
Propulsive Performance and Heating Environment of Rotating Detonation Engine with Various Nozzles
Geometric throats are commonly applied to rocket combustors to increase pressure and specific impulse. This paper presents the results from thrust measurements of an ethylene/gas-oxygen rotating detonation engine with various throat geometries in a vacuum chamber to simulate varied backpressure conditions in a range of 1.1–104 kPa. For the throatless case, the detonation channel area was regarded to be equivalent the throat area, and three throat-contraction ratios were tested: 1, 2.5, and 8. Results revealed that combustor pressure was approximately proportional to equivalent throat mass flux for all test cases. Specific impulse was measured for a wide range of pressure ratios, defined as the ratio of the combustor pressure to the backpressure in the vacuum chamber. The rotating detonation engine could achieve almost the same level of optimum specific impulse for each backpressure, whether or not flow was squeezed by a geometric throat. In addition, heat-flux measurements using heat-resistant material are summarized. Temporally and spatially averaged heat flux in the engine were roughly proportional to channel mass flux. Heat-resistant material wall compatibility with two injector shapes of doublet and triplet injection is also discussed
Feasibility and problem in managements of the patients with acute cholecystitis: A historical study at a single province institute.
Objectives: "Practice Guidelines for Acute Cholecystitis and Acute Cholangitis (in Japanese)," issued in 2005 in Japan, recommends early cholecystectomy in patients with acute cholecystitis. We evaluated the feasibility and problems in management of this condition. Method: We analyzed the clinical and laboratory data of 120 consecutive patients in whom cholecystectomy was performed for treatment of acute cholecystitis between April 2003 and March 2010 in our hospital. Results: After the Guidelines were issued, the rate of urgent operations increased (from 2.4% to 35.4%; p < 0.001) and the length of preoperative hospital stay decreased (form 12.5 days to 7.6 days; p < 0.05). Urgent operation, however, was chosen in only 35.4% of the patients even after the Guidelines were issued, mainly because of the shortage of surgeons and anesthesiologists. In these patients with moderate to severe acute cholecystitis, percutaneous cholecystostomy (PC) was performed without severe complications, followed by cholecystectomy. Conclusion: Urgent operation for acute cholecystitis has the advantages of earlier alleviation of symptoms and shorter hospital stays than PC followed by surgery or elective operation. PC followed by surgery may be a suboptimal option for patients with moderate to severe acute cholecystitis who might be able to tolerate an urgent operation, given that appropriate human resources are not available
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