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141.
142.
Masato Kobayashi Hiroshi Wakabayashi Daiki Kayano Takahiro Konishi Hironori Kojima Hiroto Yoneyama Koichi Okuda Hiroyuki Tsushima Masahisa Onoguchi Keiichi Kawai Seigo Kinuya 《Annals of nuclear medicine》2014,28(6):551-558
Purpose
High-energy (HE) collimators are usually applied for I-131 imaging after ablation treatment of differentiated thyroid cancer (DTC). However, purchase of HE collimators has been avoided in many nuclear medicine departments because the HE collimators are more expensive than other collimators. In this study, we compared the I-131 imaging using HE- and medium-energy (ME) collimators, which is more versatile than HE collimators.Materials and methods
To simulate DTC patients with extra-thyroid beds, a phantom of acrylic containers containing I-131 was used. To simulate patients with thyroid beds, four phantoms representing extra-thyroid beds were arranged around the phantom representing normal thyroid tissues. Patients administered 1.11 or 3.70 GBq NaI-131 were also evaluated. Whole-body imaging and SPECT imaging of the phantoms and patients performed using HE-general-purpose (HEGP) and ME-low-penetration (MELP) collimators, and full-width at half maximum (FWHM) and percent coefficient of variation (%CV) were measured.Results
In the extra-thyroid beds, FWHM and %CV with MELP were negligibly different from those with HEGP in whole-body imaging. Although FWHM with MELP was a little different from that with HEGP in SPECT imaging, %CV with MELP was significantly higher than that with HEGP. In the thyroid beds, only an extra-thyroid bed including higher radioactivity was identified in whole-body imaging with both collimators. Although SPECT images with MELP could not clarify extra-thyroid beds with low radioactivity, HEGP could identify them. In patients, although some whole-body images with MELP could not detect extra-thyroid beds, whole-body imaging with HEGP and SPECT imaging with both collimators could detect them.Conclusions
Although HEGP is the best collimator for I-131 imaging, MELP is applicable for not only whole-body imaging but also SPECT imaging. 相似文献143.
144.
AIM: To investigate the one-year outcomes and factors that influence the results of microhook ab interno trabeculotomy (μLOT).
METHODS: The medical records of consecutive patients with open angle glaucoma who underwent μLOT (including combination of μLOT and cataract surgery) between February 2018 and July 2019 were retrospectively reviewed. Surgical success was defined as the following: an intraocular pressure (IOP)≤21 mm Hg or IOP≤preoperative IOP with a reduced number of glaucoma eye drops, without additional glaucoma surgery, and assessed using Kaplan-Meier survival analysis. A multivariate Cox proportional-hazards regression model was used to investigate the factors associated with surgical failure.
RESULTS: The 59 eyes of 59 patients comprising 28 eyes with primary open angle glaucoma (POAG) and 31 with secondary open angle glaucoma (SOAG) were included. The mean IOP and number of glaucoma eye drops significantly decreased from 25.3±7.2 mm Hg and 3.9±1.1, preoperatively to 16.1±4.4 mm Hg (P<0.01) and 2.1±1.8 (P<0.01), respectively, 12mo postoperatively, with a cumulative success rate of 63.1%. The one-year success rate was significantly higher in POAG eyes than in SOAG eyes (80.0% vs 48.0%; P=0.011, log-rank test). Multivariate analyses revealed SOAG [P=0.017, adjusted hazard ratio (aHR): 3.468, 95%CI: 1.246-9.654] and the postoperative IOP spike (IOP>25 mm Hg within 2wk post-surgery; P<0.001, aHR: 5.382, 95%CI: 2.113-13.707) as independent factors associated with surgical failure.
CONCLUSION: The μLOT is a good treatment option for POAG eyes. However, the postoperative course should be carefully followed in cases with postoperative IOP spike. 相似文献
145.
Tumor suppressor activity and inactivation of galanin receptor type 2 by aberrant promoter methylation in head and neck cancer 下载免费PDF全文
146.
Takata T Miyazaki M Li H Healy M Frye S Tanaka K Hara S Kamimura H Yoshimura H Matsunaga A Ohta D Ishikura H Tamura K Tang YW 《Journal of infection and chemotherapy》2012,18(2):199-206
Methicillin-resistant Staphylococcus aureus (MRSA) infections have been the most common cause of nosocomial infections in Japan, but their genetic characteristics related to bloodstream infections have not been well studied. The aim of this study was to investigate a comprehensive molecular characterization of MRSA blood isolates during the historical 18-year study period between 1987 and 2004 in a tertiary care university hospital. A total of 137 MRSA isolates recovered from the blood of inpatients at Fukuoka University Hospital were analyzed. Clinical information and antimicrobial susceptibility profiles were reviewed, and staphylococcal chromosomal cassette mec (SCCmec), accessory gene regulator (agr), and a battery of bacterial genes were tested by PCR-based assays. The relatedness of these isolates was determined by the repetitive sequence-based PCR (rep-PCR) and pulsed-field gel electrophoresis (PFGE). Although low numbers of agr type III/SCCmec type IV isolates circulated between 1987 and 1992, agr type II/SCCmec type II isolates started circulating in 1993 and were responsible for the increased MRSA isolates until 2004. The rep-PCR and PFGE identified 104 epidemic and 33 sporadic isolates. Among the 104 epidemic isolates, six major rep-PCR/PFGE types were identified, which occupied 67.3% of epidemic isolates. The SCCmec type II and agr type II isolates were observed in significantly higher proportion in epidemic isolates than in sporadic isolates (P = 0.0318, P = 0.0123, respectively). In contrast, SCCmec type IV strains were observed in significantly higher proportion in sporadic isolates than in epidemic isolates (P = 0.0494). Although isolates with sec were detected in higher rates in epidemic isolates (P = 0.0397), seh was detected in higher rates in sporadic isolates (P = 0.0350). Multivariate logistic regression analysis with forward stepping revealed that SCCmec type II was independently associated with epidemic isolates (P = 0.0067; odds ratio, 1.75; 95% confidence interval, 1.17-2.64). These data indicated that SCCmec type II MRSA isolates were responsible for the increased MRSA bloodstream infections for inpatients during the 18-year study period in the hospital. 相似文献
147.
148.
149.
Daiki Abukawa Yusaku Tazawa Tomoyo Noro Michiko Nakagawa Kazuie Iinuma Kohachiro Sugiyama Alexander S. Knisely 《Pediatric and developmental pathology》2001,4(3):304-309
A 12-year-old Japanese boy had chronic elevation and fluctuation of serum transaminase levels since infancy, with no signs
or symptoms of liver failure. Usual infections or metabolic disorders were eliminated from consideration. No coagulopathy
or abnormality in plasma concentrations of clotting factors was found. Light microscopy of liver biopsy specimens obtained
at ages 2, 5, and 7 years showed slight hepatocyte disarray and minimal mononuclear-leukocyte lobular inflammation, with eosinophilic
inclusion bodies in the cytoplasm of hepatocytes throughout the lobule. These bodies stained with the periodic acid-Schiff
(PAS) technique; the PAS-positive material was partly diastase digestible and on immunostaining marked for fibrinogen but
not for α1-antitrypsin. On transmission electron microscopy, the bodies were represented by finely granular material contained within
membranes and were interpreted as tentatively endoplasmic reticulum. Fibrinogen storage may be manifest as minimal hepatitis
without coagulopathy.
Received August 12, 1999; accepted June 27, 2000. 相似文献
150.
Ever since the first introduction of the ball-type valve by Hufnagel in 1952, which was installed in the descending aorta
to correct aortic valve insufficiency, great efforts have been aimed to produce a hemodynamically and structurally superior
prosthetic heart valve. Bileaflet valves, commercially initiated by the St. Jude medical (SJM) valve, perform satisfactorily,
and now the majority of the mechanical-type prosthetic heart valves used clinically are of this type. The recent trend in
bileaflet valve design seems to be concentrated on the hinge mechanism and leaflet design to improve performance against thromboembolic
complications and hemolysis. This paper studied the effects of hinge location, leaflet configuration, valve opening angle,
and valve installed orientation to the flow field inside the simulated ventricle using laser Doppler anemometry. As a model
prosthetic valve, the SJM valve was selected as a reference, and newer bileaflet valves, including the ATS, the Carbomedics
(CM), and the Jyros (JR) valves, were selected for comparison. The test program also utilized a flow visualization technique
to map the velocity field inside the simulated ventricle to complement the information obtained using the LDA system. Comparison
of the velocity profiles at corresponding flow phases revealed the effects of the differences in valve design and orientation.
Based on precise examination of the data, the following general conclusions can be made: all valves (SJM, ATS, CM, and JR)
show distinct circulatory flow patterns when the valve is installed in the antianatomical orientation. The small differences
in hinge location and leaflet configuration can generate noticeable differences, particularly during the accelerating flow
phase of the valve. The ATS and the CM valves open less during the forward flow phase, and this results in generally diverse
and less distinct flow patterns and slower velocity. This is particularly noticeable for the flow through the central orifice.
The SJM valve maintains a relatively higher velocity through the central orifice. The curved leaflet JR valve generates higher
but divergent flow during the accelerating and peak flow phases. 相似文献