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41.
Cement mortar can be colored using color additive technology to give colorful facades to the surfaces of buildings, and to beautify the environment. In this study, weight ratios of color powder/cement at 1:80, 1:40, and 1:27, and polyacrylic emulsion/cement at a ratio of 1:5 were added as pigments to cement mortar; the fresh properties, slump, slump flow, hardened properties, compressive strength, flexural strength, ultrasonic pulse velocity, durability, surface electrical resistivity and thermal conductivity of the colored cement mortar were then examined. The results showed that adding color powder/cement at 1:80 and polyacrylic emulsion/cement at 1:5 gives the best water/cement (W/C) ratio, which equals 0.5; this can effectively improve the hardness and durability of colored cement mortar. At 28 days of aging, the strength of the various colored cement mortars was maintained at 33.1–36.8 MPa. The acrylic-based emulsion significantly improved the flexural strength of the specimen. At 91 days of aging, all of the cement mortars exceeded the control group, with an anti-bay strength of 19.9–21.7 MPa, and the strength increased with aging. Adding appropriate amounts of inorganic color powder and mixing water can effectively enhance the fresh and hardened properties and durability of the colored cement mortar, while polyacrylic emulsion may significantly improve the test pieces and flexural strength, which increases with age. Moreover, natural α-Fe2O3 (rust layer) is formed on the surface of the colored cement mortar samples through the addition of inorganic color powder that contains Fe(III) ion; this prevents the intrusion of noxious ions and thus increases the durability. All of the test pieces of colored cement mortar in this study had a surface resistance of over 20 kΩ-cm on the seventh day of the test period, meaning good surface compactness. In addition, because the thermal conductivity of the added inorganic color powder was higher than that of cement, the thermal conductivity was significantly improved. 相似文献
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Mei-Kang Yuan Ju-Wen Kao Wen-Tung Wu Chiy-Rong Chen Chi-I Chang Yu-Jen Wu 《Pharmaceutical biology》2022,60(1):1214
ContextMomordica charantia L. (Cucurbitaceae), known as bitter melon, is an edible fruit cultivated in the tropics. In this study, an active compound, 5β,19-epoxycucurbita-6,23(E)-diene-3β,19(R),25-triol (ECDT), isolated from M. charantia was investigated in regard to its cytotoxic effect on human hepatocellular carcinoma (HCC) cells.ObjectiveTo examine the mechanisms of ECDT-induced apoptosis in HCC cells.Materials and methodsThe inhibitive activity of ECDT on HA22T HCC cells was examined by MTT assay, colony formation assay, wound healing assay, TUNEL/DAPI staining, annexin V-fluorescein isothiocyanate/propidium iodide (PI) staining and JC-1 dye. HA22T cells were treated with ECDT (5, 10, 15, 20 and 25 μM) for 24 h, and the molecular mechanism of cells apoptosis was examined by Western blot. Cells treated with vehicle DMSO were used as the negative control.ResultsECDT inhibited the cell proliferation of HA22T cells in a dose-dependent manner. Flow cytometry showed that ECDT treatment at 10–20 μM increased early apoptosis by 10–14% and late apoptosis by 2–5%. Western blot revealed that ECDT treatment activated the mitochondrial-dependent apoptotic pathway, and ECDT-induced apoptosis was mediated by the caspase signalling pathway and activation of JNK and p38MAPK. Pre-treatment of cells with MAPK inhibitors (SB203580 or SP600125) reversed the ECDT-induced cell death, which further supported the involvement of the p38MAPK and JNK pathways.Discussion and conclusionsOur results indicated that ECDT can induce apoptosis through the p38MAPK and JNK pathways in HA22T cells. The findings suggested that ECDT has a valuable anticancer property with the potential to be developed as a new chemotherapeutic agent for the treatment of HCC. 相似文献
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Andrew S Kao Kayla St Claire Lisa M Bedford Darius R Mehregan Aleodor A Andea David Kouba 《International journal of clinical and experimental pathology》2022,15(4):201
Nevoid and myxoid melanoma are rare variants of melanoma; association of the two is a unique finding. Nevoid melanoma is characterized by morphologic resemblance to a nevus, whereas myxoid melanoma demonstrates a basophilic mucinous matrix. We present an atypical case of a melanoma progressing from a nevoid melanocytoma with myxoid changes. A 78-year-old female presented with a pigmented growth on her right thigh. Biopsy demonstrated a biphenotypic melanocytic proliferation composed of a nodule showing epithelioid melanocytes with enlarged nuclei, prominent nucleoli, lack of maturation, and abundant amphophilic cytoplasm with a rare mitotic figure. These findings were suggestive of melanoma along with a nevoid dermal component and myxoid stroma. FISH testing revealed a homozygous loss of 9p21 in the atypical component. SNP-microarray from the nevoid component demonstrated three abnormalities including a gain of whole chromosome 8, as well as loss of a copy of nearly an entire chromosome 9 and 16q most consistent with a melanocytoma. 相似文献
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Hao-Wei Chen Yu-Chen Chen Jung-Ting Lee Frances M. Yang Chung-Yao Kao Yii-Her Chou Ting-Yin Chu Yung-Shun Juan Wen-Jeng Wu 《Nutrients》2022,14(9)
There is a great need for a diagnostic tool using simple clinical information collected from patients to diagnose uric acid (UA) stones in nephrolithiasis. We built a predictive model making use of machine learning (ML) methodologies entering simple parameters easily obtained at the initial clinical visit. Socio-demographic, health, and clinical data from two cohorts (A and B), both diagnosed with nephrolithiasis, one between 2012 and 2016 and the other between June and December 2020, were collected before nephrolithiasis treatment. A ML-based model for predicting UA stones in nephrolithiasis was developed using eight simple parameters—sex, age, gout, diabetes mellitus, body mass index, estimated glomerular filtration rate, bacteriuria, and urine pH. Data from Cohort A were used for model training and validation (ratio 3:2), while data from Cohort B were used only for validation. One hundred and forty-six (13.3%) out of 1098 patients in Cohort A and 3 (4.23%) out of 71 patients in Cohort B had pure UA stones. For Cohort A, our model achieved a validation AUC (area under ROC curve) of 0.842, with 0.8475 sensitivity and 0.748 specificity. For Cohort B, our model achieved 0.936 AUC, with 1.0 sensitivity, and 0.912 specificity. This ML-based model provides a convenient and reliable method for diagnosing urolithiasis. Using only eight readily available clinical parameters, including information about metabolic disorder and obesity, it distinguished pure uric acid stones from other stones before treatment. 相似文献
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V.C. Yang C.-H. Kao W.-H. Ting K.-Y. Chen B.-N. Chiang 《International journal of radiation biology》2013,89(6):1225-1241
SummaryA single dose of 8 or 20 Gy 60Co γ-rays was given to C3H male mice at 4 months of age. Degenerative changes in the cardiac muscle due to brain irradiation were observed first at 6 months after irradiation, and became progressively more severe at 12–24 months. The changes seen at the ultrastructural level included myofibrillolysis, the presence of lysosomal-like bodies and interstitial fibrosis. Ultrastructural changes in the control cardiac muscle throughout the experimental period were monitored and only minor aging changes were noted. The coronary arteries of control mice began to show a slight amount of smooth muscle degeneration and fibrosis 1 year into the experiment. At 18 months the lesions became more severe, and at 24 months there was relatively less distinction between the control and the 20 Gy treated group. Degenerative changes in the coronary arteries were noticed at 6 months after irradiation, and became progressively more severe at later times (12–24 months). The major changes included smooth muscle degeneration with fibrosis and the accumulation of debris and extracellular matrix. At 18 months the medial smooth muscle showed severe damage, with accumulations of matrix material and debris. There was additional fibrosis in the adventitial layer. There were few additional changes at 24 months after 20 Gy irradiation. Quantitative analyses indicated that the average fractional volumes of degenerated smooth muscle cells were 13, 27 and 39% in the unirradiated group at 12, 18 and 24 months, respectively, and 13 and 29% in the sham-irradiated group at 12 and 18 months into the experiment, respectively. These percentages were 12, 32 and 49% (P < 0·05) after 8 Gy irradiation, and 19% (P < 0·05), 46% (P < 0·01), and 42% after 20 Gy irradiation, respectively. 相似文献
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BACKGROUND: Hematopoietic cell transplantation (HCT) is performed in more than 25,000 patients annually. Clinically significant bacterial transmission from HCT products is rare. CASE REPORT: A 36‐year‐old male of Asian descent with chronic myelogenous leukemia developed sepsis leading to acute renal failure and disseminated intravascular coagulation during infusion of matched unrelated donor bone marrow. This product later tested positive for Bacillus cereus. DISCUSSION: This HCT product traveled 31 hours at room temperature before arriving at the transplant center. Reducing transport times, transporting at 4°C, and enhancing bacterial surveillance of HCT products may increase the ability to detect bacterial proliferation from transport. CONCLUSION: To prevent a similar case in the future, we will begin Gram staining all HCT products in transit more than 24 hours to alert physicians of the need for prophylactic antibiotic therapy. 相似文献