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91.
ObjectiveIn cases of head and neck cancer treated with intra-arterial chemotherapy, no objective indices are available for determining the distribution of anticancer drugs administered to multiple arteries. To establish such indices, noninvasive measurements of drug concentrations are required in the arterial perfusion area of each artery. In MRI, changes in 1/T1 (Δ1/T1) are correlated with the contrast agent concentration. We focused on these properties and investigated whether it is possible to estimate anticancer drug concentrations within tissue based on Δ1/T1.MethodsWe employed the fast spin echo (FSE) sequence to determine optimum imaging parameters using a phantom. Subsequently, contrast agent was administered via the lingual and external carotid arteries for seven cases of tongue cancer. Δ1/T1 were then measured in tumor and nontumor tissues. The results of this study were compared with those of a previous study in which intratumor concentrations of anticancer agent were measured in excised specimens.ResultsThe optimum imaging parameters for the FSE was two repetition times (TR, 500 and 1000 ms). When compared with the external carotid artery administration, the lingual artery administration of contrast agent resulted in significantly higher Δ1/T1 in both tumor and nontumor tissues (2.13 and 2.62 times, respectively). The multiplying factor for the nontumor tissue and high homogeneity of the contrast agent concentration were reasonably consistent with the results of the previous study.ConclusionThis method can be applied to estimating intratissue concentrations of intra-arterially administered anticancer drugs, thus possibly providing useful information in determining the distribution of anticancer drugs.  相似文献   
92.
ObjectiveFibrotic changes in the vocal fold mucosa have been observed in patients with vocal fold scarring, aged vocal fold, and sulcus vocalis, which often lead to severe voice disorders. Previous research suggests that the basic fibroblast growth factor (b FGF) improves variations in vocal fold properties [1,2]. Although clinical studies on b FGF treatments have been conducted [3,4,5], these studies only demonstrated the efficacy of this drug over a short period. The present study is the first to investigate the long-term efficacy of b FGF treatment.Methodsb FGF injections were performed in six patients from January of 2016 to December of 2017 at our institution. Patient follow-up continued for at least two years after the last injection. Three patients had vocal fold scarring, two had aged vocal fold atrophy, and one patient had sulcus vocalis. Each vocal fold was injected with 10 µg of b FGF four times. Voice and stroboscopic examinations were performed after surgery (at one month, three months, six months, one year, two years). Fundamental frequency, maximum phonation time (MPT), mean flow rate (MFR), amplitude perturbation quotient (APQ), pitch perturbation quotient (PPQ), and noise-to-harmonic ratio (NHR), and voice handicap index-10 (VHI-10) were examined and compared statistically between the pretreatment time and at each posttreatment time point.ResultsThe speaking F0 had an obvious decreasing tendency, with significant differences suggesting the increase in volume in the vocal folds. Aerodynamic parameters also showed small improvements. The most remarkable improvement was observed in the acoustic parameters, indicating that the treatment could improve the vocal fold to make vibrations symmetrically and regularly for a long period. Achievement of symmetry and regularity on vocal fold vibrations suggested the property changes had happened in the vocal folds. Consequently, the score of VHI-10 had improved, indicating high patient satisfaction with this treatment.Conclusionb FGF injections could be a reliable treatment option for diseases that deteriorate the property of vocal fold.  相似文献   
93.
The purpose of this study was to analyze passive motion of the para- and retropharyngeal space (PRS) during swallowing using dynamic magnetic resonance imaging (MRI). We conducted a preliminary study involving 30 healthy volunteers who underwent dynamic MRI. Consecutive MRI axial images were obtained by examining the plane parallel to the hard palate at the level of the anterior inferior corner of C2. Anterior displacement of the posterior pharyngeal wall (PPW) was measured as a motion index of pharyngeal contraction. The displacement and internal angle of the bilateral external and internal carotid arteries (ECA and ICA) and the bilateral centroids of the PRS area, as well as the increase in PRS area, were calculated at rest and at maximum pharyngeal contraction. In most participants, the bilateral ECA, ICA, and centroids were anterointernally displaced by pharyngeal contraction. The normalized ECA displacement (r = 0.64, r 2 = 0.41), normalized ICA displacement (r = 0.60, r 2 = 0.37), and normalized centroid displacement (r = 0.43, r 2 = 0.19) were more than moderately positively correlated with the normalized PPW displacement. The normalized PRS area increase (r = 0.35, r 2 = 0.12) was weakly positively correlated with the normalized PPW displacement. These results revealed that PRS area increased as the ECA and ICA were drawn anterointernally via its passive motion by pharyngeal contraction.  相似文献   
94.
Annals of Nuclear Medicine - The aim of the study was to investigate the outcomes and prognostic factors of high-dose 131I-metaiodobenzylguanidine (131I-MIBG) therapy in patients with refractory or...  相似文献   
95.
The day of the week of admission may influence the length of stay and in-hospital death. However, the association between the admission day of the week and in-hospital outcomes has been inconsistent in heart failure (HF) patients among studies reported from Western countries. We thus analyzed this association in HF patients encountered in routine clinical practice in Japan. We studied the characteristics and in-hospital treatment in 1620 patients hospitalized with worsening HF by using the database of the Japanese Cardiac Registry of Heart Failure in Cardiology (JCARE-CARD). Patients were divided into two groups according to weekday (n = 1355; 83.6 %) or weekend admission (n = 265; 16.4 %). The mean age was 70.7 years and 59.4 % were male. Etiology was ischemic in 34.0 %, and mean left ventricular ejection fraction was 42.5 %. Patients admitted on the weekend were significantly older and had more comorbidities, and more severe symptoms and signs of HF on admission. Length of stay was comparable between weekend and weekday admission (35.2 ± 47.0 days vs 33.6 ± 32.0 days, P = 0.591). Crude in-hospital mortality did not differ between patients admitted on the weekend and weekdays (7.5 % vs 5.2 %, P = 0.136). Even after adjustment for covariates in multivariable modeling with patients admitted on weekday as the reference, in-hospital death was comparable between patients admitted on the weekend and weekdays (adjusted odds ratio 1.125, 95 % confidence interval 0.631–2.004, P = 0.691). Among patients hospitalized for worsening HF, admission day of the week did not affect in-hospital death and length of stay.  相似文献   
96.
A 46-year-old woman underwent upper endoscopy for evaluation of anemia, which revealed whitish granules at the duodenal papilla, diagnosed as duodenal follicular lymphoma (DFL) by biopsy. Computed tomography and abdominal ultrasonography revealed that follicular lymphoma was confined to the duodenum. Seven years after the diagnosis, fluorine-18 fluorodeoxyglucose positron emission tomography scanning revealed multiple lesions including in bone marrow and lymph nodes. Bone marrow biopsy of the right iliac bone revealed diffuse large B-cell lymphoma, indicating systemic dissemination and histologic transformation of the DFL. The patient responded to chemotherapy and has been progression-free for 2.5 years. Although DFL is usually indolent even without any treatment, systemic dissemination with histologic transformation can occur. This case suggests that the life-time follow-up that is usually done for patients with nodal follicular lymphoma should be provided to patients with DFL.  相似文献   
97.
98.
H7N9 influenza virus infection in humans was reported in China on March 31, 2013. Humans are immunologically naïve to the H7N9 subtype, for which the seasonal influenza vaccine is not effective. Thus, the development of an H7N9 influenza virus vaccine is an urgent issue. To prepare for the emergence of an influenza pandemic, we have established a library comprising more than 1300 influenza virus strains with 144 different combinations of 16 HA and 9 NA subtypes. An H7N9 virus strain isolated from a 35-year-old woman, A/Anhui/1/2013 (H7N9), was found to be antigenically similar to H7N9 influenza viruses isolated from migratory ducks. In the present study, the potency of an inactivated whole virus particle vaccine prepared from an H7N9 low pathogenic avian influenza virus, A/duck/Mongolia/119/2008 (H7N9), selected from the library, was assessed by a challenge with A/Anhui/1/2013 (H7N9). The results indicate that the test vaccine was potent enough to induce sufficient immunity to reduce the impact of disease caused by the challenge with A/Anhui/1/2013 (H7N9) in mice. The present results indicate that an inactivated whole virus particle vaccine prepared from an influenza virus strain stored in the library could be useful as a vaccine strain in case of an influenza pandemic.  相似文献   
99.
100.
This study investigated adequate liver graft selection for donor safety by comparing postoperative donor liver function and morbidity between the right and left hemilivers (RL and LL, respectively) of living donors. Between April 2006 and March 2012, RL (n = 168) and LL (n = 140) donor operations were performed for liver transplantation at Kyoto University Hospital. Postoperative hyperbilirubinemia and coagulopathy persisted in RL donors, whereas the liver function of LL donors normalized more rapidly. The overall complication rate of the RL donors was significantly higher than that of the LL donors (59.5% vs. 30.7%; P < 0.001). There were no significant differences in severe complications worse than Clavien grade IIIa or in biliary complication rates between the two donor groups. In April 2006, we introduced an innovative surgical procedure: hilar dissection preserving the blood supply to the bile duct during donor hepatectomy. Compared with our previous outcomes (1990–2006), the biliary complication rate of the RL donors decreased from 12.2% to 7.2%, and the severity of these complications was significantly lower. In conclusion, LL donors demonstrated good recovery in postoperative liver function and lower morbidity, and our surgical innovations reduced the severity of biliary complications in living donors.  相似文献   
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