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991.
In this paper, we described a straightforward one-step chemical method for the synthesis of semiconductor quantum dots(QDs)—block copolymer brushes functionalized graphene oxide(GO) fluorescence nanohybrids. The azobenzene-terminated block copolymer poly(N-isopropylacrylamid)-b-poly(styrene-co-5-(2-methacryoylethyloxymethyl)-8-quinolinol)(PNIPAM-b-P(St-co-MQ)) was modified on the surface of GO sheets via host–guest interactions between β-cyclodextrin-modified GO and azobenzene moieties, and simultaneously CdSe/ZnS QDs were integrated on the block copolymer brushes through the coordination between 8-hydroxyquinoline units in the polymer brushes and CdSe/ZnS QDs. The resulting fluorescence nanohybrid exhibited dual photoluminescence at 620 nm and 526 nm, respectively, upon excitation at 380 nm and LCST-type thermo-responsive behavior which originated from the change in the PNIPAM conformation in the block copolymer brushes of GO sheets.  相似文献   
992.
The tensile bond strength between zirconia subjected to different surface-pretreatment methods and methacryloyloxydecyl-dihydrogen-phosphate (MDP)-containing self-adhesive resin cement was evaluated herein. Eighty-eight cylindrical zirconia specimens were randomly divided into the following four groups based on the pretreatment method: (1) no treatment, (2) air abrasion, (3) HNO3/HF etching, and (4) zirconia-nanoparticle coating. The tensile bond strength of the zirconia–resin-cement complexes was investigated. One-way ANOVA and post hoc tests were performed at a 95% significance level, and the Weibull modulus was calculated. Fracture patterns were visualized by SEM. The surface roughness of the specimens without resin bonding was evaluated by AFM. The tensile bond strength of the specimens decreased as follows: Groups 3 > 4 > 2 > 1 (28.2 ± 6.6, 26.1 ± 5.7, 16.6 ± 3.3, and 13.9 ± 3.0 MPa, respectively). Groups 3 and 4 had significantly higher tensile bond strengths (p < 0.05) and lower fracture probabilities than those of Groups 1 and 2. They also showed both mixed failure and resin-cement cohesive failure, whereas Groups 1 and 2 showed mixed failure exclusively. The zirconia–resin tensile bond was stronger after HNO3/HF etching or ZrO2-nanoparticle coating than after air abrasion or no treatment. The estimated surface roughness decreased as follows: Groups 3 > 4 > 2 > 1. The combination of zirconia pretreated with HNO3/HF etching or ZrO2-nanoparticle coating and an MDP-containing self-adhesive resin cement can increase the clinical longevity of zirconia restorations by preventing their decementation.  相似文献   
993.
Hyperuricemia is one of the independent risk factors for atherosclerotic cardiovascular disease. Herein, we investigate the association between uric acid and cholesterol metabolism and the effect of dioscin on the prevention of hyperuricemia-induced atherosclerosis. In the potassium oxonate-treated ApoE−/−−/− mice, atherosclerosis was accelerated along with elevated serum cholesterol levels in the hyperuricemic state, which can be ameliorated by dioscin. Together with the in vitro assays, we found that the effect of dioscin was at least partially through the regulation of the farnesoid X receptor (FXR) -small heterodimer partner (SHP) -7α-hydroxylase (CYP7A1) signaling pathway in the liver. Tigogenin (a metabolite of dioscin) suppressed FXR activation and increased CYP7A1, resulting in an increased conversion rate of cholesterols into bile acids. Further clinical study revealed that treatment with a dioscin-enriched preparation decreased serum cholesterol levels in individuals with hyperuricemia. In summary, this study demonstrated a slowdown effect of dioscin on the progression of hyperuricemia-induced atherosclerosis.  相似文献   
994.
BackgroundThe clinical significance of serum collagen triple helix repeat protein‐1 (CTHRC1) and mitotic spindle apparatus antibody (MSA) in the diagnosis of small cell lung cancer (SCLC).MethodsOf the 229 lung tumor patients selected, 62 patients were divided into SCLC, 94 patients with non‐small cell lung cancer (NSCLC), and 73 patients with benign lung disease (BLD). The health controls (HC) had a span of 66 cases with normal physical condition. The serum extracted from each participator and enzyme‐linked immunosorbent assay was adopted for measuring the serum CTHRC1 and MSA; in the meantime, automatic electrochemiluminescence immunoassay was used for the quantitative determination of serum NSA and CEA. And then, the differences in serum CTHRC1, MSA, NSE, and CEA were compared among involved groups.Results① Compared with other groups, the concentrations of CTHRC1, MSA, and NSE showed a marked increase in the group of SCLC (all p < 0.01). Especially for SCLC patients with lymph node metastasis, CTHRC1 provided a notably higher level than those without metastasis. ② CTHRC1 and MSA established a diagnostic criterion with the specificity of 90.99% and 86.27% for SCLC, respectively. ③ In series, the specificity of CTHRC1 and NSE was the highest (99.30%), while MSA and NSE had the highest sensitivity (96.72%) in parallel. ④ Both CTHRC1 and MSA were hazardous factors interconnected with SCLC.ConclusionSerum CTHRC1 and MSA had a more exciting prospect of application. When used in conjunction with NSE and CEA, they could optimize the clinical diagnosis value of SCLC.  相似文献   
995.
Glutamine (Gln) is required for intestinal mucosal homeostasis, and it can promote triglyceride absorption. The intestinal mucosal mast cells (MMCs) are activated during fat absorption. This study investigated the potential role of Gln on fat absorption-induced activation of MMCs in rats. Lymph fistula rats (n = 24) were studied after an overnight recovery with the infusion of saline only, saline plus 85 mM L-glutamine (L-Gln) or 85 mM D-glutamine (D-Gln), respectively. On the test day, rats (n = 8/group) were given an intraduodenal bolus of 20% Intralipid contained either saline only (vehicle group), 85 mM L-Gln (L-Gln group), or 85 mM D-Gln (D-Gln group). Lymph was collected hourly for up to 6 h for analyses. The results showed that intestinal lymph from rats given L-Gln had increased levels of apolipoprotein B (ApoB) and A-I (ApoA-I), concomitant with an increased spectrum of smaller chylomicron particles. Unexpectedly, L-Gln also increased levels of rat mucosal mast cell protease II (RMCPII), as well as histamine and prostaglandin D2 (PGD2) in response to dietary lipid. However, these effects were not observed in rats treated with 85 mM of the stereoisomer D-Gln. Our results showed that L-glutamine could specifically activate MMCs to degranulate and release MMC mediators to the lymph during fat absorption. This observation is potentially important clinically since L-glutamine is often used to promote gut health and repair leaky gut.  相似文献   
996.
目的观察苦参、土槿皮、黄柏、百部、黄连、虎杖、黄芩、大黄、藿香、五倍子及其混合液体外抑制念珠菌的效果。方法参照1997年美国国家临床实验标准化委员会M27-A方案中的酵母菌微量稀释法进行药敏试验。结果同一种中药水煎剂及不同的单味中药水煎剂对不同的念珠菌标准菌株的最低抑菌浓度(minimuminhibitory concentration,MIC)各不相同,中药混合液对5种标准菌株的MIC最低,均≤0.031 25g/ml。结论不同的中药对不同的念珠菌的抑制作用各不相同,复方对念珠菌的抑制作用优于单味中药。  相似文献   
997.
Persistent generalized low bone mineral density (BMD) has been reported in patients with adolescent idiopathic scoliosis (AIS).However,the exact mechanisms and causes of the low BMD in AIS patients are largely unknown.The purpose of this study was to examine the relationship between the receptor activator of NF-κB ligand (RANKL)/osteoprotegerin (OPG) levels in osteoblasts (OBs) from AIS patients with low BMD and with comparison made between the patients and controls.Twenty AIS patients and eight age-matched controls were included in the present study.The BMD of lumbar spine and proximal femur was measured in all subjects.OBs from the cancellous bone of each subject was harvested and primarily cultured.The mRNA and protein expression of RANKL and OPG in OBs was detected by RT-PCR and Western blotting.The results showed BMD was lower in AIS patients than in controls.A significantly higher mRNA and protein expression of RANKL was observed in OBs from AIS patients,while no significant difference was found in the expression of OPG between AIS patients and controls.As a result,RANKL/OPG ratio in patients with AIS was remarkably higher than controls.Our study preliminarily demonstrated expression of RANKL was higher in OBs from AIS patients with low BMD as compared with controls,suggesting the unbalanced RANKL/OPG ratio caused by an over-expression of RANKL in OBs may be responsible for the low BMD in AIS patients.  相似文献   
998.
999.
通过电子化学习技术(E-learning),将现有的网络资源和应急救援数字化教学培训相结合,充分利用现代信息技术所提供的全新沟通机制与丰富资源,为应急救援培训提供一个受众面更为广阔的平台,进一步为培训基地开展应急救援培训提供科学的、互动的、个性化的和不受时空约束的教学管理平台.该平台有利于各级人员根据自我需求制定各自的...  相似文献   
1000.
检测人表皮生长因子(hEGF)在胃癌组织中的含量,初步探讨其临床意义。用放射免疫分析法测定52例胃癌切除标本和18例正常胃粘膜组织中hEGF的含量。结果:对照组为1.49±0.95ng/g湿重,胃癌组织为4.29±2.35ng/g湿重,差异显著(P<0.01)。在胃癌组织中,hEGF含量进展期高于早期,弥漫型高于肠型,淋巴结转移阳性者高于阴性者,近期随访发现胃癌患者死亡组的hEGF含量较高。结论:胃癌组织可产生过量的hEGF,并与肿瘤浸润、组织分化程度、淋巴结转移等相关,提示胃癌组织hEGF测定可作为判断胃癌生物学行为及了解患者预后的指标。  相似文献   
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