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91.
The study investigated the potential of Elaeocarpus sylvestris var. ellipticus (E.S.), which contains 1,2,3,4,6-penta-O-galloyl-beta-D-glucose (PGG), to protect mice from radiation injury by single whole-body irradiation (WBI) in vivo. The results from the present study demonstrate that the E.S. extract significantly improved the rate and duration of survival beyond that of untreated, irradiated control mice. The counts of endogenous colony forming units (CFU) increased in E.S.-treated mice, indicating that E.S. induced the regeneration of hematopoietic cells. E.S. treatment also accelerated the proliferation and recovery of lymphocytes and granulocytes, compared with those levels in untreated, irradiated controls. These results suggest that E.S. extract increases the survival time of mammals exposed to ionizing radiation by intensifying the victims' hematopoietic repair capacities. Therefore, it is concluded that the E.S. extract may be an effective agent of protection from radiation-induced injuries.  相似文献   
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OBJECTIVE: Early detection through regular screening could significantly reduce mortality from ovarian cancer. Advances in biomarkers and imaging continue to improve the sensitivity and specificity of cancer detection, but further improvements are still needed. In this study, we identified and evaluated three new serum biomarkers that may be used to improve detection of ovarian cancer. METHODS: Through genomic analysis, we identified B7-H4, Spondin 2, and DcR3 as over-expressed genes in ovarian cancer tissues. Sensitive sandwich ELISAs were developed to analyze the level of these novel markers in 68 serum samples from patients with ovarian cancer (16 early stage, 52 late stage) and 108 control samples, and 20 healthy women from which two serum samples were collected 1 year apart. CA125 levels were measured in all samples. RESULTS: Markers were evaluated for their ability to identify clinical disease. The three novel markers and CA125 were elevated in serum of ovarian cancer patients as compared to normal controls. B7-H4 showed the highest specificity, with the lowest frequency of elevation in all control groups. When all cases were compared against all controls, CA125, Spondin 2, B7-H4, and DcR3 showed areas under the ROC curve of 0.87, 0.78, 0.74, and 0.71, respectively. CA125 and B7-H4 showed the best diagnostic performance for early-stage, with AUCs of 0.90 and 0.80, respectively. CONCLUSION: This study demonstrates that B7-H4, Spondin 2, and DcR3 are promising new ovarian cancer markers that may improve early detection of cancer when used in combination with traditional diagnostic tests.  相似文献   
94.
BACKGROUND: Neuroendocrine carcinoma of the non-small cell type of the ovary is a rare aggressive tumor, interestingly associated with either a surface epithelial tumor or teratoma. CASE: A 71-year-old woman presented with a pelvic mass and underwent a total abdominal hysterectomy with a bilateral salpingo-oophorectomy. Pathology examination showed a 6.5 cm in greatest dimension ovarian tumor composed of neuroendocrine carcinoma of the non-small cell type and serous carcinoma. Immunohistochemical studies including keratin 7, WT-1, and neuroendocrine markers demonstrated differences in the two components. Microsatellite instability (MSI) analysis using five polymorphic markers also showed a different pattern in the two components. CONCLUSION: This is the first report of an ovarian neuroendocrine carcinoma, non-small cell type, associated with a serous carcinoma. Immunohistochemistry and MSI are very helpful in making a definite diagnosis.  相似文献   
95.
The roles of social workers in hospitals have changed in accordance with the environmental changes in the healthcare system. Since 1958, hospital social workers have performed important roles in providing care services in South Korea. Providing psychosocial services was considered to be the most important for more than 30 years from the 1970s to the 1990s. The healthcare system has since undergone major environmental changes, yet there has been little study on the role of hospital social workers in South Korea. In order to address this research gap, this study aims to explore how the roles of hospital social workers have changed since the 2000s. We recruited 198 hospital social workers who were active members of the Korean Association of Medical Social Workers as study participants. The average age of participants was 35.36 years old (SD = 8.27), and they had an average of 8.24 years in hospital social work experience (SD = 6.35). The results indicated that the roles of financial support and community resource linkage, which were regarded to be relatively less important until the 1990s, were recognized as the most important. Given the role changes of hospital social workers in South Korea, implications are discussed.  相似文献   
96.
PurposeInterleukin (IL)-17A has been suggested to play a role in the growth and organization of thrombi. We examined whether IL-17A plays a role in the early stages of thrombosis and whether there are sex differences in the effects of IL-17A.Materials and MethodsWe performed a blinded, randomized, placebo-controlled study to compare time to thrombotic occlusion and sex differences therein between mice treated with IL-17A and those treated with saline using a ferric chloride-induced model. We also assessed thrombus histology, blood coagulation, and plasma levels of coagulation factors.ResultsTime to occlusion values did not differ between the IL-17A group and the control group (94.6±86.9 sec vs. 121.0±84.4 sec, p=0.238). However, it was significantly shorter in the IL-17A group of female mice (74.6±57.2 sec vs. 130.0±76.2 sec, p=0.032). In rotational thromboelastometry, the IL-17A group exhibited increased maximum clot firmness (71.3±4.5 mm vs. 66.7±4.7 mm, p=0.038) and greater amplitude at 30 min (69.7±5.2 mm vs. 64.5±5.3 mm, p=0.040) than the control group. In Western blotting, the IL-17A group showed higher levels of coagulation factor XIII (2.2±1.5 vs. 1.0±0.9, p=0.008), monocyte chemoattractant protein-1 (1.6±0.6 vs. 1.0±0.4, p=0.023), and tissue factor (1.5±0.6 vs. 1.0±0.5, p=0.003).ConclusionIL-17A plays a role in the initial st ages of arterial thrombosis in mice. Coagulation factors and monocyte chemoattractant protein-1 may be associated with IL-17A-mediated thrombosis.  相似文献   
97.
复合自适应滤波器用于体感诱发电位信噪比的提高   总被引:1,自引:0,他引:1  
本研究以可靠、快速提取体感诱发电位为目标,试图解决相干叠加方法既费时又不能反映体感诱发电位时变特征的缺点。运用以自适应噪声减法器和自适应增强器为基础构造的复合自适应滤波器提取体感诱发电位。仿真实验表明,运用复合自适应滤波器可实现从强噪声背景中快速提取体感诱发电位,能更快地识别体感诱发电位的潜伏期及幅值,并且系统性能稳定。  相似文献   
98.
Seasonal variations in vestibular neuritis (VN) could support the etiology of viral infection. However, several recent studies revealed no significant seasonal variations in VN. Further studies are necessary to determine the etiology of VN. We analyzed patients with VN to evaluate monthly and seasonal variations. Patients with VN who visited our otorhinolaryngology department or were referred to our department from the emergency department between March 2014 and February 2019 were included retrospectively in this study. Differences among the months and seasons of VN visits were analyzed. Patients were divided into 2 groups according to sex and age (65 years or older and younger than 65 years). Differences among the months and seasons of VN visits were analyzed between groups. There were no significant differences in monthly and seasonal distributions in 248 patients with VN. There were also no significant differences in monthly and seasonal distributions in male and female patients or in older and younger patients. There were no significant differences in monthly or seasonal distributions of patients with VN. Factors other than viruses, such as vascular ischemia, should also be considered in the incidence of VN, especially in older patients.  相似文献   
99.
BackgroundParticulate matter (PM) is an air pollutant that can impair the human skin. Antioxidants have been tested to improve PM-induced skin inflammation.ObjectiveIn this study, we investigated the effects of dieckol on PM-induced inflammation on cultured human sebocytes, outer root sheath (ORS) cells, and mice pretreated with Cutibacterium acnes.MethodsWe cultured and treated the sebocytes and ORS cells with 5 µM of dieckol and 100 µg/ml of PM10 for 24 h. The C. acnes-pretreated mice received 5 µM of dieckol and 100 µg/ml of PM10. We measured cell viability using MTT assay. Real-time PCR and measurement of reactive oxygen species (ROS) and sebum production analyzed the effects.ResultsDieckol inhibited the upregulation of the gene expression of the inflammatory cytokines, matrix metalloproteinase (MMP), aryl hydrocarbon receptor, and nuclear factor kappa-light-chain-enhancer of activated B cells by PM10 in the cultured sebocytes and ORS cells and inhibited an increase in ROS production by PM10 in the cultured sebocytes. In addition, dieckol decreased the inflammatory cytokines, MMP, and sebum production in C. acnes-pretreated mice.ConclusionDieckol effectively reduced the expression of inflammatory biomarkers and the production of sebum in cultured sebocytes, ORS cells, and C. acnes-pretreated mice.  相似文献   
100.
何为"老"?理解衰老的最好办法是将其视为一种从生到死的过度和渐变过程.在人们眼中,一旦到了80岁,身体就会变得很衰弱,易受伤,易残疾.但凡事都有例外,最典型的例子就是著名的黑人领袖纳尔逊.曼德拉,他虽年事已高(88岁),但他的才学、智慧、饱经磨难和乐观豁达都是少有人能及的.  相似文献   
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