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61.
Ceftriaxone (CTRX) forms salts with calcium (Ca) in the gall bladder and bile duct, and induces the formation of gallstones. In this study, factors of CTRX-induced gallstone formation were extracted from the results of a retrospective survey using the Japanese Adverse Drug Event Report (JADER), and the causal relationship between the factors and gallstone formation was investigated. From JADER, 136 patients who developed ‘gallstone-related disorder’ with CTRX as a suspected drug were extracted. The incidence of gallstone-induced adverse effects was high in patients treated with CTRX at a dose exceeding the normal daily dose and in children younger than 10 years old, suggesting that CTRX at a high level is a factor for gallstone formation. Thus, after mixing CTRX and Ca2+ at different concentrations under different pH condition, the number of particles in the solutions was measured using a Coulter counter. As a result, the number of minute particles significantly increased at all pH values when Ca2+ and CTRX were mixed at a concentration of 10 mEq/L or higher and 1.5 g/L or higher, respectively. At pH 6.5 or 7.0, visible crystals were detected when 25 mEq/L of Ca2+ and 2.0 g/L of CTRX were mixed. Based on these findings, attention should be sufficiently paid to the development of ‘gallstone-related disorder’ in pediatric patients and in patients treated with CTRX at a dose exceeding the normal dose. Furthermore, gallstone formation and growth may be promoted when CTRX and Ca2+ coexist at high concentrations under low pH conditions.  相似文献   
62.

Background

The treatment planning for Gamma Knife (GK) stereotactic radiosurgery (SRS) that performs dose calculations based on tissue maximum ratio (TMR) algorithm has disadvantages in predicting dose in tissue heterogeneity. The latest version of the planning software is equipped with a convolution dose algorithm as an optional extra and the new algorithm is able to compensate for head inhomogeneity. However, the effect of this improved calculation method requires detailed validation in clinical cases. In this study, we compared absolute and relative dose distributions of treatment plans for acoustic neurinoma between TMR and the convolution calculation.

Methods

Twenty-nine clinically used plans created by TMR algorithm were recalculated by convolution method. Differences between TMR and convolution were evaluated in terms of absolute dose (beam-on time), dosimetric parameters including target coverage, selectivity, conformity index, gradient index, radical homogeneity index and the dose-volume relationship.

Results

The discrepancy in estimated absolute dose to the target ranged from 1 to 7 % between TMR and convolution. In addition, dosimetric parameters of the two methods achieved statistical significance. However, it was difficult to see the change of relative dose distribution by visual assessment on a monitor.

Conclusions

Convolution, heterogeneity correction calculation, and the algorithm are necessary to reduce the dosimetric uncertainty of each case in GK SRS.  相似文献   
63.
IntroductionPostoperative dysphonia is mostly caused by vocal fold scarring, and careful management of vocal fold surgery has been reported to reduce the risk of scar formation. However, depending on the vocal fold injury, treatment of postoperative dysphonia can be challenging.ObjectiveThe goal of the current study was to develop a novel prophylactic regenerative approach for the treatment of injured vocal folds after surgery, using biodegradable gelatin hydrogel microspheres as a drug delivery system for basic fibroblast growth factor.MethodsVideoendoscopic laryngeal surgery was performed to create vocal fold injury in 14 rabbits. Immediately following this procedure, biodegradable gelatin hydrogel microspheres with basic fibroblast growth factor were injected in the vocal fold. Two weeks after injection, larynges were excised for evaluation of vocal fold histology and mucosal movement.ResultsThe presence of poor vibratory function was confirmed in the injured vocal folds. Histology and digital image analysis demonstrated that the injured vocal folds injected with gelatin hydrogel microspheres with basic fibroblast growth factor showed less scar formation, compared to the injured vocal folds injected with gelatin hydrogel microspheres only, or those without any injection.ConclusionA prophylactic injection of basic fibroblast growth factor -containing biodegradable gelatin hydrogel microspheres demonstrates a regenerative potential for injured vocal folds in a rabbit model.  相似文献   
64.
Journal of Natural Medicines - A new crinine-type alkaloid crijaponine A (1), a new galanthamine-type alkaloid crijaponine B (2), and 11 known alkaloids—ungeremine (3), lycorine (4),...  相似文献   
65.
The substances associated with PM2.5‐induced inflammatory response were investigated using an elimination method. PM2.5 were heated at temperatures of 120, 250, and 360°C. The results demonstrated microbial substances such as LPS and b‐glucan, and chemicals including BaP, 1,2‐NQ, and 9,10‐PQ were reduced drastically in PM2.5 heated at 120°C. On the other hand, DBA, 7,12‐BAQ, and BaP‐1,6‐Q were not noticeably reduced. Most of these substances had disappeared in PM2.5 heated at 250°C and 360°C. Metals (eg, Fe, Cu, Cr, Ni) in PM2.5 exhibited a slight thermo‐dependent increase. RAW264.7 macrophages with or without NAC were exposed to unheated PM2.5, oxidative stress‐related and unrelated inflammatory responses were induced. PM2.5‐induced lung inflammation in mice is caused mainly by thermo‐sensitive substances (LPS, b‐glucan, BaP, 1,2‐NQ, 9,10‐PQ, etc.). Also, a slight involvement of thermo‐resistant substances (DBA, 7,12‐BAQ, BaP‐1,6‐Q, etc.) and transition metals was observed. The thermal decomposition method could assist to evaluate the PM2.5‐induded lung inflammation.  相似文献   
66.
European Radiology - To evaluate the feasibility of assessment of microvessel perfusion of pituitary adenomas with intravoxel incoherent motion (IVIM) imaging using single-shot turbo...  相似文献   
67.
We report a case of active infective endocarditis in a young adult, affecting the anterior and posterior leaflets extensively. The patient underwent a mitral valve repair with extended sliding repair on the posterior leaflet and reconstruction using an autologous pericardial patch supported by an artificial chord on the anterior leaflet. Although we finally needed commissure closing for successful repair, we aggressively achieved a repair-oriented strategy using several techniques in a young patient who may have required mitral valve replacement.  相似文献   
68.
We report three presenile patients who were initially suspected of having Alzheimer's disease (AD) or being in the prodromal stage of AD, regardless of visuoperceptual dysfunctions in daily living, because they lacked the core features and prodromal non‐motor symptoms of dementia with Lewy bodies. Subsequently, progression to dementia with Lewy bodies was suspected based on neuropsychological and neuroimaging findings; additionally, one of the three patients suffered from visual hallucinations. Neuropsychological examinations such as subjective contours, cube copying and block design in the Wechsler Adult Intelligence Scale‐III revealed visuoperceptual dysfunction in all three patients even when other cognitive functions were rather preserved. Brain magnetic resonance imaging revealed no significant brain atrophy, including in the parieto‐occipital area and the hippocampus, while brain 18F‐fluorodeoxyglucose positron emission tomography demonstrated right dominant metabolic reductions in the occipital lobe, including the primary visual cortex, in all three patients. We suggest the possibility of progression to dementia with Lewy bodies, but not AD or posterior cortical atrophy. Regardless of the presence of core features and prodromal non‐motor symptoms, this progression is suggested when there are difficulties only in higher‐level visual processing such as subjective contours and block design in the Wechsler Adult Intelligence Scale‐III, no significant atrophy of the parieto‐occipital area and hippocampus on brain magnetic resonance imaging, and hypometabolism in the occipital lobe including the primary visual cortex on brain 18F‐fluorodeoxyglucose positron emission tomography.  相似文献   
69.
The aim of this study was to examine the applicability of the linear-quadratic (LQ) model to single and fractionated irradiation in EMT6 cells. First, the α/β ratio of the cells was determined from single-dose experiments, and a biologically effective dose (BED) for 20 Gy in 10 fractions (fr) was calculated. Fractional doses yielding the same BED were calculated for 1-, 2-, 3-, 4-, 5-, 7-, 15- and 20-fraction irradiation using LQ formalism, and then irradiation with these schedules was actually given. Cell survival was determined by a standard colony assay. Differences in cell survival between pairs of groups were compared by t-test. The α/β ratio of the cells was 3.18 Gy, and 20 Gy in 10 fr corresponded to a BED3.18 of 32.6 Gy. The effects of 7-, 15- and 20-fraction irradiation with a BED3.18 of 32.6 Gy were similar to those of the 10-fraction irradiation, while the effects of 1- to 5-fraction irradiation were lower. In this cell line, the LQ model was considered applicable to 7- to 20-fraction irradiation or doses per fraction of 2.57 Gy or smaller. The LQ model might be applicable in the dose range below the α/β ratio.  相似文献   
70.
The latest version of Leksell GammaPlan (LGP) is equipped with Digital Imaging and Communication in Medicine (DICOM) image-processing functions including image co-registration. Diagnostic magnetic resonance imaging (MRI) taken prior to Gamma Knife treatment is available for virtual treatment pre-planning. On the treatment day, actual dose planning is completed on stereotactic MRI or computed tomography (CT) (with a frame) after co-registration with the diagnostic MRI and in association with the virtual dose distributions. This study assesses the accuracy of image co-registration in a phantom study and evaluates its usefulness in clinical cases. Images of three kinds of phantoms and 11 patients are evaluated. In the phantom study, co-registration errors of the 3D coordinates were measured in overall stereotactic space and compared between stereotactic CT and diagnostic CT, stereotactic MRI and diagnostic MRI, stereotactic CT and diagnostic MRI, and stereotactic MRI and diagnostic MRI co-registered with stereotactic CT. In the clinical study, target contours were compared between stereotactic MRI and diagnostic MRI co-registered with stereotactic CT. The mean errors of coordinates between images were < 1 mm in all measurement areas in both the phantom and clinical patient studies. The co-registration function implemented in LGP has sufficient geometrical accuracy to assure appropriate dose planning in clinical use.  相似文献   
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