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91.
Although artificial porous materials are useful for dissipating acoustic waves, they pose a major environmental threat as most are non-recyclable. Developing sustainable structural materials with the mechanical and energy-absorption properties required to replace artificial porous materials is currently a key challenge. Here, we report, for the first time, a novel microstructure using all-natural moss with a compressive strength of up to 2.35 GPa and a sound-absorption performance of up to 90%, depending on the additives, such as yogurt, starch, and beer. In addition, the moss-based microstructure was applied as graffiti to a three-dimensionally printed house model to demonstrate improved performance against the effects of sound. By incorporating energy-absorbing materials without harmful substances, the desired structure can be decorated with the graffiti method. This work could pave the way for attenuating sound-wave and impact noise by using graffiti work on structural composite materials.  相似文献   
92.
Choi BH  Kim W  Wang QC  Kim DC  Tan SN  Yong JW  Kim KT  Yoon HS 《Cancer letters》2008,261(1):37-45
Here, we demonstrate that kinetin riboside (KR), a cytokinin analog, induces apoptosis in HeLa and mouse melanoma B16F-10 cells. KR disrupted the mitochondrial membrane potential and induced the release of cytochrome c and activation of caspase-3. Bad were upregulated while Bcl-2 was down-regulated under KR exposure. A tumor growth in mice was dramatically suppressed by KR. In contrast, human skin fibroblast CCL-116 and bovine primary fibroblast cells show resistances to KR and no significant changes in Bad, Bcl-X(L,) and cleaved PARP were observed. Our data suggest that KR selectively induces apoptosis in cancer cells through the classical mitochondria dependent apoptosis pathway.  相似文献   
93.
ObjectiveTo investigate the long-term outcomes of percutaneous treatment of benign biliary strictures using temporary placement of a retrievable expanded polytetrafluoroethylene (PTFE) covered stent.Materials and MethodsWe retrospectively analyzed the outcomes of 148 patients (84 male and 64 female; age range, 11–92 years) who underwent percutaneous transhepatic placement and removal of a retrievable PTFE-covered stent for the treatment of benign biliary strictures between March 2007 and August 2019 through long-term follow-up. Ninety-two patients had treatment-naïve strictures and 56 had recurrent/refractory strictures.ResultsStent placement was technically successful in all 148 patients. The mean indwelling period of the stent was 2.4 months (median period, 2.3 months; range, 0.2–7.7 months). Stent migration, either early or late, occurred in 28 (18.9%) patients. Clinical success, defined as resolution of stricture after completing stent placement and removal, was achieved in 94.2% (131 of 139 patients). The overall complication rate was 15.5% (23 of 148 patients). During the mean follow-up of 60.2 months (median period, 52.7 months; range, 1.6–146.1 months), 37 patients had a recurrence of clinically significant strictures at 0.5–124.5 months after removal of biliary stent and catheter (median, 16.1 months). The primary patency rates at 1, 3, 5, 7, and 10 years after removal of biliary stent and catheter were 88.2%, 70.0%, 66.2%, 60.5%, and 54.5%, respectively. In the multivariable Cox proportional hazard regression analysis, sex, age, underlying disease, relation to surgery, stricture type, biliary stones, history of previous treatment, and stricture site were not significantly associated with the primary patency.ConclusionLong-term outcomes suggest that percutaneous treatment of benign biliary strictures using temporary placement of retrievable PTFE-covered stents may be a clinically effective method.  相似文献   
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ObjectiveVaccination with the first licensed dengue vaccine is recommended only for those who have had previous infection with dengue virus (DENV). A point-of-care test with the desired sensitivity of 95% and specificity of 98% could facilitate pre-vaccination screening. We evaluated a newly developed, automated dengue immunoglobulin fluorescence immunoassay for determining dengue serostatus.MethodsWe used serum samples collected just prior to a mass dengue vaccination in Cebu, Philippines. Healthy children residing in Bogo and Balamban who would be 9–14 years old at the time of the mass dengue vaccination were eligible to participate. We evaluated the ichroma? II dengue fluorescence immunoassay (Boditech Med Incorporated, Gang-won-do, Republic of Korea) using a neutralization test (NT) as the reference assay.ResultsWe enrolled 2996 children (mean age 10.39 years, 51.7% female) in the cohort and included a subsample of 1000 (mean age 10.56 years, 54.4% female) in this study. Of the 1000 children, 86/1000 (8.6%) tested seronegative and 914/1000 (91.4%) seropositive for DENV antibodies by neutralization testing. Compared with the NT, the dengue IgG fluorescence immunoassay had an overall specificity of 90.7% (95%CI: 82.5–95.9%) and a sensitivity of 91.8% (95%CI: 89.8–93.5%) for determining dengue seropositivity. The sensitivity declined to 51.2% (42.3–61.0%) for the detection of the subset with a monotypic dengue profile.ConclusionThe insufficient specificity and sensitivity (particularly in the detection of a previous monotypic dengue infection) would render the test, in its current state, inadequate for pre-vaccination screening. Considering its user-friendly interphase and possibility of point-of-care use, the test could be further developed and validated to improve its performance characteristics.  相似文献   
98.
Stickler syndrome is a genetic disorder of connective tissue. One of the major symptoms associated with this disorder is an oro-facial malformation, which may cause a submucous cleft or a complete cleft of the hard palate. A 32-year-old man diagnosed with Stickler syndrome and a submucosal cleft palate (SMCP) visited our hospital with a chief complaint of excessive daytime sleepiness. The patient was diagnosed with severe obstructive sleep apnea (OSA), and administration of a polysomnography test revealed an apnea-hypopnea index (AHI) of 30.9 events/hour (h). Auto-titrating continuous positive airway pressure was initiated to control the OSA symptoms and subsequently the patient showed some improvement. However, due to continuous velopharyngeal insufficiency symptoms, intravelar veloplasty was performed. Three months after surgery, the AHI had decreased to 12.4 events/h. Recent studies have described a greater risk for OSA in individuals with cleft palate, than in the general population. The present case demonstrates surgical success in a patient with OSA and SMCP, suggesting that palatal surgery may be considered an optional surgical treatment for OSA patients with SMCP.  相似文献   
99.
OBJECTIVE: Experimental and clinical studies support a role for the fetus in the control of the onset of labor. Fetal systemic inflammation, but not a maternal inflammatory response, has been linked to the onset of preterm labor and delivery on the basis of the determination of inflammatory cytokines in fetal and maternal blood. We propose that parturition requires fetomaternal cooperation and that inflammation is an integral part of the parturitional process. This study used flow cytometry, a sensitive technique for the detection of intravascular inflammation, to assess whether maternal inflammation is present in preterm labor. STUDY DESIGN: A prospective cross-sectional study was performed including patients with preterm labor (n = 55) and women with normal pregnancy (n = 50). Intravascular inflammation was studied by using flow cytometry. Maternal blood was assayed to determine granulocyte and monocyte phenotype by using monoclonal antibodies, which included the following cluster of differentiation (CD) markers: CD11b, CD14, CD15, CD16, CD18, CD49d, CD62L, CD64, CD66b, and HLA-DR. Oxidative burst and generation of basal intracellular oxygen radical species were assessed. Statistical analysis was conducted with the use of nonparametric methods. A P value of <.01 was considered statistically significant. RESULTS: Preterm labor was associated with a significant increase in the median mean channel brightness of CD11b, CD15, and CD66b on granulocytes and median mean channel brightness of CD11b and CD15 on monocytes. The ratio of oxidative burst over basal intracellular oxygen radical species in both granulocytes and monocytes was increased in preterm labor (P <. 01). CONCLUSION: Preterm labor with intact membranes is associated with phenotypic and metabolic changes of maternal granulocytes and monocytes.  相似文献   
100.
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