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991.
目的 探讨急性心肌梗死(AMI)和心房纤维性颤动(AF)患者血小板膜糖蛋白CD62P、CD63与vWF临床检测的意义。方法采用流式细胞技术和夹心酶免疫吸附试验检测AMI和AF患者CD63、CD62P和vWF的变化。结果 AMI和AF患者的CD62P分别为11.29%和8.72%、CD63分别为8.72%和2.66%,明显高于对照组(3.37%和1.32%),AMI组的vWF为167.83%,明显高于对照组(102.71%),AF组为117.05%,与对照组比较无显著性差异。结论急性心肌梗死和心房纤维性颤动患者CD62P和CD63的表达水平明显增高,进一步证实CD62P和CD63为血栓形成的血小板活性物质,参与血栓性疾病的促凝血作用。 相似文献
992.
993.
Jiwon M. Lee Young Seo Park Joo Hoon Lee Se Jin Park Jae Il Shin Yong‐Hoon Park Kee Hwan Yoo Min Hyun Cho Su‐Young Kim Seong Heon Kim Mee Kyung Namgoong Seung Joo Lee Jun Ho Lee Hee Yeon Cho Kyoung Hee Han Hee Gyung Kang Il Soo Ha Jun‐Seok Bae Nayoung K. D. Kim Woong‐Yang Park Hae Il Cheong 《Pediatrics international》2015,57(3):431-438
994.
995.
ABSTRACT Previously, a synbiotic combination of probiotic Lactobacillus gasseri 505 (LG) and a new prebiotic, Cudrania tricuspidata leaf extract (CT) in fermented milk, designated FCT, showed an in vitro immunomodulatory effect and antioxidant activity. Although synbiotic combination might have cancer-protective effects, these activities have not been fully validated in vivo. Ten-week treatment of LG, CT, or FCT to azoxymethane (AOM)/dextran sodium sulfate (DSS)-induced colitis-associated colorectal cancer (CAC) mouse model reduced both the incidence of colonic tumors and damage to the colonic mucosa effectively, suggesting a cancer-protective effect. To understand these, biomarkers associated with inflammation, colon barrier, apoptosis, and cancer cell proliferation were monitored in AOM/DSS group versus LG/CT/FCT groups. A synbiotic combination (FCT) down-regulated pro-inflammatory cytokines (TNF-α, IFN-γ, IL-1β, and IL-6) and inflammation-associated enzymes (iNOS and COX-2), and up-regulated anti-inflammatory cytokines (IL-4 and IL-10). In addition, colon barrier experiment revealed that biomarkers of mucus layer (MUC-2 and TFF3) and tight junction (occludin and ZO-1) were up-regulated. Subsequent apoptosis experiment showed that pro-apoptotic factors (p53, p21, and Bax) were up-regulated and anti-apoptotic factors (Bcl-2 and Bcl-xL) were down-regulated. Furthermore, comparative metagenome analysis of gut microbiota revealed that Staphylococcus decreased but Lactobacillus, Bifidobacterium, and Akkermansia increased, supporting their protective effects, accompanied by increased short-chain fatty acids (SCFAs). Taken together, the FCT administration showed cancer-protective effects by reducing the risk of colitis-associated colon cancer via regulation of inflammation, carcinogenesis, and compositional change of gut microbiota. Consequently, the synbiotic combination (FCT) could be a novel potential health-protective natural agent against CAC. 相似文献
996.
Dong Hyun Kim Jae Hee Cho Su Hyun Lee Hyun Ki Kim Seung Min Bang Si Young Song Jae Bock Chung Seung Woo Park 《Taehan Sohwagi Hakhoe chi》2008,51(2):142-146
Compared with other types of cancers, pancreatic cancer is one of the most dreadful malignancies and is fifth leading cause of cancer-related death in Korea. It is difficult to expect early diagnosis or improvement in prognosis due to lack of specific early symptoms and effective diagnostic methods. Whereas cystic neoplasm of the pancreas is a rare type of pancreatic tumor, surgical resection provides good prognosis because of its low possibility of local invasion or distant metastasis. In case of pancreatic cystic tumor, radiologic differentiation between benign and malignant lesions is crucial for the selection of appropriate treatment and the prediction of prognosis. And ductal adenocarcinoma of pancreas presenting in cystic form is an uncommon type of cystic tumor, making it extremely rare among all pancreatic malignancies. We report two cases of atypical pancreatic ductal adenocarcinoma presenting as solid pseudopapillary tumor and intraductal papillary mucinous neoplasm, respectively. 相似文献
997.
目的:探讨对肝癌介入治疗患者实施综合护理干预对患者生活质量的影响。方法将采用放射介入治疗的肝癌患者100例,采用随机数字表法分为对照组50例和观察组50例,对照组采用常规护理方法,观察组在常规护理的基础上实施不舒适原因评估、心理干预、休息指导、饮食指导、健康教育、训练放松、术后药物反应和并发症护理等综合护理。观察比较两组患者术后不良反应发生情况和护理效果。结果术后两组患者化疗药物不良反应比较,观察组患者恶心呕吐、穿刺处出血、排尿或排便困难的发生率均低于对照组,差异均有统计学意义(χ2值分别为11.947,4.000,6.618;P<0.05)。观察组患者对术后不良反应的耐受情况、对介入治疗知识的掌握、生活质量的改善情况均优于对照组,差异有统计学意义(χ2值分别为13.301,19.869,4.762;P<0.05)。结论综合护理干预能减轻患者身心压力,减少术后不良反应,提高生活质量,值得推广应用。 相似文献
998.
Byung-Kuk Yoo Zixue Su John Meurig Thomas Ahmed H. Zewail 《Proceedings of the National Academy of Sciences of the United States of America》2016,113(3):503-508
Understanding the dynamical nature of the catalytic active site embedded in complex systems at the atomic level is critical to developing efficient photocatalytic materials. Here, we report, using 4D ultrafast electron microscopy, the spatiotemporal behaviors of titanium and oxygen in a titanosilicate catalytic material. The observed changes in Bragg diffraction intensity with time at the specific lattice planes, and with a tilted geometry, provide the relaxation pathway: the Ti4+=O2− double bond transformation to a Ti3+−O1− single bond via the individual atomic displacements of the titanium and the apical oxygen. The dilation of the double bond is up to 0.8 Å and occurs on the femtosecond time scale. These findings suggest the direct catalytic involvement of the Ti3+−O1− local structure, the significance of nonthermal processes at the reactive site, and the efficient photo-induced electron transfer that plays a pivotal role in many photocatalytic reactions.Single-site catalysts of both the thermally and photoactivated kind now occupy a prominent place in industrial- and laboratory-scale heterogeneous catalysis (1–8). Among the most versatile of these are the ones consisting of coordinatively unsaturated transition metal ions (Ti, Cr, Fe, Mn…) that occupy substitutional sites in well-defined, three-dimensionally extended, open-structure silicates of the zeolite type. The well-known and most widely used are the 4- or 5-coordinated Ti(IV) ions accommodated within the crystalline phase of silica, silicalite (9–14).Titanosilicates, especially, are used extensively both industrially and in the laboratory for a wide range of chemo-, regio-, and shape-selective oxidations of organic compounds (15–18). These single-site heterogeneous photocatalysts are quite distinct from those typified by TiO2, SrTiO3, and other titaniferous photocatalysts where the Ti(IV) ions are in 6-coordination; and where, in interpreting the processes involved in harnessing solar radiation, electronic band structure considerations hold sway in preference to the localized states (see, e.g., refs. 19, 20). It has been demonstrated (16–18, 21, 22) that single-site, coordinatively unsaturated Ti(IV)-centered photocatalysts are especially useful in the aerial oxidation of environmental pollutants in the photodegradation of NO (to N2 and O2), of H2O (to H2 and O2), and in the photocatalytic reduction of CO2 to yield methanol. There is an exigent need to explore the precise nature of the electronic, temporal, and spatial changes accompanying the initial act of photoabsorption that sets in train the ensuing elementary chemical processes that are of vital environmental significance in, for example, the utilization of anthropogenic CO2 as a chemical feedstock (23).Here, we report the use of 4D ultrafast electron microscopy (UEM) (24–26) to trace the spatiotemporal behavior of the Ti(IV) and O2− ions at the photocatalytic active center in the structurally well-characterized titanosilicate Na4Ti2Si8O22·4H2O, known as JDF-L1 (27–29). JDF stands for Jilin–Davy–Faraday, as the crystalline solid described here was discovered and characterized in joint work involving Jilin University (P. R. China) and the Davy–Faraday Laboratory at the Royal Institution of Great Britain. L1 stands for the first layered catalyst formed during that collaboration; 5-coordinated solids containing Ti(IV) ions are rare among the hundred or so titaniferous minerals, the prime example being fresnoite, Ba2Ti2Si2O8. We choose this photocatalyst with 5-coordinated Ti because of its unique bonding structure. Our approach entails monitoring, at femtosecond resolution, the changes in intensities and anisotropies of Bragg (electron) diffraction reflections in such a manner as to retrieve the change in valency and the time scales involved in both the formation of Ti3+−O1− bond and the relaxation of the energy back to the local structure of the Ti = O bond in JDF-L1. Through these diffraction studies, and the associated Debye–Waller effect and structural factors anisotropies, it is found that a Ti3+−O1− bond is formed on the femtosecond time scale; whereas, the back relaxation from the site to the structure occurs on a much longer time scale, permitting ample time for reactivity involving Ti3+−O1−, and indicating the potential significance of nonthermal processes in the photocatalytic activity at the reactive site. 相似文献
999.
Immunologic status of hemophilia patients treated with cryoprecipitate or lyophilized concentrate 总被引:1,自引:0,他引:1
We evaluated 37 patients with moderate or severe hemophilia A and six patients with severe factor IX deficiency for clinical or laboratory evidence of immune abnormalities. Patients were assigned to one of four groups according to the type of clotting factor replacement. Twenty patients had received only cryoprecipitate during the two years preceding the evaluation (group I); 11 additional patients were treated predominantly with cryoprecipitate but had also received up to nine bottles of factor VIII concentrate (group II); six patients received factor VIII concentrate (group III); six patients received factor IX concentrate (group IV). There was no clinical or laboratory evidence of immunodeficiency among the 43 patients. The mean absolute number of Th cells was normal in all patient groups, but the mean absolute number of Ts cells was increased compared with controls, both in patients treated with cryoprecipitate and in patients treated with factor VIII or factor IX concentrate. There was no correlation between the Th/Ts ratio and patient age, alanine aminotransferase level, hepatitis serology, in vitro lymphocyte function, or amount of clotting factor administered. Our observations demonstrate that the volunteer or commercial origin of clotting factor replacement cannot fully explain the alterations in lymphocyte subset distribution previously described in patients with hemophilia A. 相似文献
1000.
Clearance of hepatitis B surface antigen (HBsAg) after surgical resection of hepatocellular carcinoma 总被引:1,自引:0,他引:1
The serum HBsAg in 4 chronic HBsAg carrier patients with hepatocellular carcinoma (HCC) cleared within 4-38 months after surgical resection of their hepatic tumors. Two patients developed anti-HBs. During the follow-up period from 21 to 28 months after HBsAg clearance, none of the patients regained positive serum HBsAg. Two patients who had had tissue HBsAg present, exclusively in the tumor, showed quick HBsAg clearance after resection. The other 2 patients had a delayed HBsAg clearance. One had tissue HBsAg in both the tumor and nontumoral liver. Only 1 patient had tissue HBsAg in the liver, but not in the tumor. During the same period of observation of 323 chronic HBsAg carriers, who had a variety of histologically-verified chronic liver diseases and were followed for more than 6 months, only 1 cleared the antigen. The spontaneous HBsAg clearance in our HBsAg carriers (1/323) was significantly lower than that (4/64) of HBsAg-positive HCC patients with tumor resection, P less than 0.004. The mechanisms of HBsAg clearance in HCC patients after surgical resection of tumors are discussed. 相似文献