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41.
A newly established catalyst system for oxygen‐oxidative polymerization of diphenyl disulfide is reported. Combination of vanadyl compounds (e.g., VO(acac)2) and triphenylmethylium tetrakis(pentafluorophenyl)borate (TrB(C6F5)4) proceeds the polymerization to give poly(1,4‐phenylene sulfide) (PPS) at 100 °C. When triphenylmethylium tetrafluoroborate (TrBF4) is applied with vanadyl tetraphenylporphyrin (VO(TPP)) or N,N′‐(ethylenebis(salicylideneaminato))oxovanadium (VO(salen)), PPS is also given via polymerization under conditions near 160 °C. Combination of the vanadyl complex and the borate affords the first protic‐acid‐free catalytic system for the polymerization of the disulfide, suggesting the overall reaction to produce PPS and H2O from O2 and protons that are eliminated from the monomer.

  相似文献   

42.
Malignant melanoma is one of the lethal malignant tumors worldwide. Previously we reported that adenylate cyclase‐associated protein 2 (CAP2), which is a well‐conserved actin regulator, was overexpressed in hepatocellular carcinoma; however, CAP2 expression in other clinical cancers remains unclear. The aim of the current study was to clarify the clinicopathological significance of CAP2 overexpression in malignant melanoma. Immunohistochemical analyses revealed that many melanoma cells exhibited diffuse cytoplasmic expression of CAP2, whereas no normal melanocytes showed detectable immunostaining for CAP2. A high level of CAP2 expression was seen in 14 of 50 melanomas and was significantly correlated with greater tumor thickness and nodular melanoma subtypes. In addition, a high level of CAP2 expression was associated with poor overall survival in univariate and multivariate analyses. For 13 patients, samples of primary and metastatic melanoma tissue were available: four patients exhibited higher levels of CAP2 expression in metastatic tumor compared to the primary site, whereas no patient showed lower levels of CAP2 expression in metastatic melanomas. Our findings show that CAP2 overexpression is a novel prognostic marker in malignant melanoma and that CAP2 expression seems to increase stepwise during tumor progression, suggesting the involvement of CAP2 in the aggressive behavior of malignant melanoma.  相似文献   
43.

Purpose

The aim of this study was to clarify whether ultrasound quantitative methods were positively correlated with volume of ascites evaluated by whole abdominopelvic CT.

Methods

Sixty-eight patients with cirrhotic ascites were retrospectively analyzed. First, to confirm that virtual ultrasonography (VUS) is an alternative method to conventional ultrasound, 22 patients underwent both conventional ultrasonography and VUS. Second, the efficacy of US quantitative methods (3-point method, 4-point method, 5-point method, and Matsumoto’s method) was confirmed by VUS in 68 patients. We assessed whether the ascites volume predicted by VUS corresponded with that calculated by 3D-CT. Of the 68 patients, 23 patients were analyzed before and after administration of tolvaptan.

Results

The predictive volumes calculated by VUS were remarkably relative to those yielded by conventional US. Correlations between exact volume and those measured by VUS were significantly high (3-point method: r?=?0.882, p?<?0.001; 4-point method: r?=?0.797, p?<?0.001; 5-point method: r?=?0.836, p?<?0.001; Matsumoto’s method: r?=?0.453, p?<?0.001). Correlations between decreasing volume on 3D-CT and that measured by VUS were also significantly high in patients with administration of tolvaptan.

Conclusion

Ascites volume measured by ultrasound was effective, especially the 3-point and 5-point methods. It was useful to assess the efficacy of diuretics in cirrhotic patients.
  相似文献   
44.
We herein report a unique form of autoimmune pancreatitis (AIP) spreading along the main pancreatic duct (MPD). A 70-year-old man was referred for a small lesion at the pancreatic neck, accompanying an adjacent cyst and dilated upstream MPD. Four years earlier, health checkup images had shown a pancreatic cyst but no mass lesion. Endoscopic ultrasonography showed a contrast-enhanced, tumorous lesion, mainly occupying the MPD. With a preoperative diagnosis of ductal neoplasms mainly spreading in the MPD, Whipple''s resection was performed. The resected specimens showed MPD periductitis with IgG4-related pathology, indicating type 1 AIP. Clinicians should practice caution concerning the various AIP forms.  相似文献   
45.
A 23-year-old man had an 8-day history of fatigue and dry cough and papulo-nodular reactions on his extensive tattoos. Chest radiography revealed several small granular shadows, and a transbronchial lung biopsy showed non-caseating epithelioid cell granuloma. A skin biopsy of the tattooed area showed histiocytic infiltrates with phagocytized tattoo pigment. Antibody tests for hepatitis C virus were positive. The patient was successfully treated with corticosteroid therapy, and after inflammation was suppressed, he received delayed anti-viral therapy. Sarcoidosis should be considered as a concurrent condition if papules are presented on the tattoos of patients with hepatitis C.  相似文献   
46.
Annals of Nuclear Medicine - Although previous studies have investigated age and gender effects on striatal subregional dopamine transporter (DaT) binding, these studies were mostly based on a...  相似文献   
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Objective: In 2020, coronavirus disease-2019 (COVID-19) became the cause of a pandemic. In response, the Japan Sports Agency issued warnings about secondary damage to health, such as the threat to physical and mental well-being due to the lack of exercise in this situation. In this study, we report on cross-sectional and longitudinal examinations of standing trunk flexion to evaluate how temporary long-term school closures affected musculoskeletal function in elementary school students.Patients and Methods: All children in one public elementary school in T-city during the school years 2019 and 2020 were included in this study. A digital forward flexion meter was used to measure standing trunk flexion.Results: In this study, 284 (284/289: 98.3%) and 266 (266/274: 97.1%) children in school years 2020 and 2019, respectively, were found to have valid data for cross-sectional analysis. The standing trunk flexion did not show significant differences between grades or sexes. In the longitudinal analysis, the results of the comparison of standing trunk flexion in children for two consecutive years revealed significant differences only between grades 3 and 4 (P<0.05) and between girls in grades 3 and 4 (P<0.01), but no significant differences in other grades or among boys or girls were observed.Conclusion: Initially, we expected that there would be a difference in the results of functional assessment using standing trunk flexion depending on the period of absence from school. However, the results of this study showed no significant changes in standing trunk flexion. Moreover, since children’s musculoskeletal functions may be affected by various factors during the COVID-19 pandemic, they should be carefully monitored in the future.  相似文献   
50.
Objectives:The purpose of this study was to evaluate the usefulness of Hounsfield unit (HU) assessment with multislice-CT in the differentiation of radicular cysts (RCs), dentigerous cysts (DCs) and odontogenic keratocysts (OKCs).Methods:In total, 307 odontogenic cysts (RCs, DCs and OKCs) were included in this study. Cysts with lesion diameter <10 mm, cysts with artefacts affecting measurement of HU values, cysts involving infection and recurrent cysts were regarded as exclusion criteria. Images were acquired in three different types of CT scanners: Aquilion ONE, Discovery CT750 HD and SOMATOM Definition Flash. Differences in HU values among scanners and among types of odontogenic cysts were assessed using one-way analysis of variance; multiple comparisons were performed post hoc, using the Tukey–Kramer honestly significant difference test.Results:In total, 164 cysts were analysed in this study (64 RCs, 57 DCs and 43 OKCs). Regardless of the type of lesion, the Aquilion ONE scanner demonstrated a significant difference in HU value, compared with the Discovery CT750 HD scanner. Regardless of CT scanner model, HU values significantly differed between DCs and OKCs (p < 0.0001), as well as between OKCs and RCs (p < 0.0001).Conclusions:HU values were found to vary among CT scanners and should always be associated with other lesion imaging features while interpreting and elaboration diagnostic hypothesis. Notably, the results suggested that OKCs might be able to be differentiated from DCs and RCs by using HU values.  相似文献   
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