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1.
We present a method to theoretically achieve multispectral narrowband light absorption in common metal-dielectric-metal nanocavities. Polarization-independent and wide-angle multi-band light absorption with absorbance up to 99 % is achieved owing to the excitation of multiple localized plasmon cavity modes. Strong interactions between plasmon resonances and photonic modes are further introduced for achieving sharp absorption spectrum with sub-10-nm bandwidth via a high-index dielectric spacer with a thickness exceeding λ/2. These findings can offer new perspectives for multispectral nano-optics devices including perfect light absorbers and subtractive polychromatic filters.  相似文献   
2.

Background

Endoscopic resection and gastrectomy are treatment modalities for early gastric cancer, but their relative benefits and risks are unclear. We conducted a systematic review and meta-analysis to compare endoscopic resection and gastrectomy for treating early gastric cancer.

Methods

We searched PubMed, Embase, and the Cochrane Library until April 2015 for studies comparing endoscopic resection with gastrectomy for treatment of early gastric cancer. Outcome measures were five-year overall survival (OS), length of hospital stay and postoperative morbidity. We calculated pooled hazard ratio (HR), weighted mean difference (WMD) and odds ratio (OR) using random effects models.

Results

Six studies comprising 1,466 patients (618 endoscopic resection and 848 gastrectomy) met inclusion criteria. Five-year OS was similar between endoscopic resection and gastrectomy (HR, 1.06; 95%CI: 0.61 to 1.83). Endoscopic resection was associated with shorter hospital stays (WMD, -6.94; 95%CI: -7.59 to -6.29) and reduced overall postoperative morbidity (OR, 0.36; 95%CI: 0.17 to 0.74).

Conclusions

While five-year OS is similar between endoscopic resection and gastrectomy, endoscopic resection offers a shorter hospital stay and fewer complications than gastrectomy for treating early gastric cancer. Endoscopic resection is a reasonable treatment for early gastric cancer with a negligible risk of lymph node metastasis.  相似文献   
3.
脑中风是严重危害我国中老年人身体健康的主要疾病之一,对中风相关基因单核苷酸多态性位点在人群中分布情况的研究将有助于深入认识中风发病机制及提高防治能力。该研究用寡核苷酸芯片方法检测了8个多态性位点与中风易感性之间的关联。结果发现:寡核苷酸芯片技术作为一种很好的基因分型方法,具有高通量、平行性、微量化、自动化和快速灵敏等的特点,适用于大规模基因分型平台的建立;实验初步发现与中风易感性相关的有血管紧张素原(AGT)基因M235T(OR=3.437,CI=1.211,9.709),载脂蛋白E(APOE)基因cys158arg (OR=9.434,1.686-83.3),亚甲基四氢叶酸还原酶(MTHFR)基因C677T(OR=2.591,1.002-6.711),血管紧张素ⅡⅠ型受体(AT1R)基因A1166C(OR=0.213,0.057-0.799)。  相似文献   
4.
Oxidative stress is regarded as a key regulator in the pathogenesis of prolonged hyperoxia-induced lung injury, which causes injury to alveolar epithelial cells and eventually leads to development of bronchopulmonary dysplasia (BPD). Many studies have shown that hydrogen has a protective effect in a variety of cells. However, the mechanisms by which hydrogen rescues cells from damage due to oxidative stress in BPD remains to be fully elucidated. This study sought to evaluate the effects of hydrogen on hyperoxia-induced lung injury and to investigate the underlying mechanism. Primary type II alveolar epithelial cells (AECIIs) were divided into four groups: control (21% oxygen), hyperoxia (95% oxygen), hyperoxia + hydrogen, and hyperoxia + hydrogen + LY294002 (a PI3K/Akt inhibitor). Proliferation and apoptosis of AECIIs were assessed using MTS assay and flow cytometry (FCM), respectively. Gene and protein expression were detected by quantitative polymerase chain reaction (q-PCR) and western blot analysis. Stimulation with hyperoxia decreased the expression of P-Akt, P- FoxO3a, cyclinD1 and Bcl-2. Hyperoxic conditions increased levels of Bim, Bax, and Foxo3a, which induced proliferation restriction and apoptosis of AECIIs. These effects of hyperoxia were reversed with hydrogen pretreatment. Furthermore, the protective effects of hydrogen were abrogated by PI3K/Akt inhibitor LY294002. The results indicate that hydrogen protects AECIIs from hyperoxia-induced apoptosis by inhibiting apoptosis factors and promoting the expression of anti-apoptosis factors. These effects were associated with activation of the PI3K/Akt/FoxO3a pathway.  相似文献   
5.
In vitro flowers have been obtained by culturing thin epidermal cell layers of a partial somatic intergeneric hybrid. The phenotype of these flowers differs from that of flowers formed on seed-grown plants (in situ flowers) and from that of flowers of either parental line. In addition, modifications in the phenotype were observed when cultures were sustained for more than four months. Dimorphic leaves present in juvenile and adult stages of mother plants of Nicotiana plumbaginifolia and the somatic hybrid were formed on different ends of the thin epidermal cell layers. No anomalies were observed during microsporogenesis and in the meiotic and mitotic figures of the somatic hybrid, which resembled those of Nicotiana plumbaginifolia.  相似文献   
6.
When thin cell layers (TCLn), isolated from the nodalregion of the hypocotyl of 5 day old seedlings, werecultured in medium M1 with IAA and BA, entire plantswere obtained from L. mutabilis explants andprolific shoots from L. albus explants.Histological studies carried out on L. mutabilisTCLn showed that meristematic cells, present in theexplants at the time of inoculation, gave rise to theformation of a primary meristem resulting inorganogenesis. In TCLn where apical or axillarymeristematic cells were absent, we observed theformation of a nodular structure with a cambium-likelayer at its periphery which divided to form a primarymeristem leading to organogenesis. Plant regenerationfrom TCLn may be useful in genetic transformationassays.  相似文献   
7.
8.
One of the fundamental goals of genetics is to understand gene functions and their associated phenotypes. To achieve this goal, in this study we developed a computational algorithm that uses orthology and protein-protein interaction information to infer gene-phenotype associations for multiple species. Furthermore, we developed a web server that provides genome-wide phenotype inference for six species: fly, human, mouse, worm, yeast, and zebrafish. We evaluated our inference method by comparing the inferred results with known gene-phenotype associations. The high Area Under the Curve values suggest a significant performance of our method. By applying our method to two human representative diseases, Type 2 Diabetes and Breast Cancer, we demonstrated that our method is able to identify related Gene Ontology terms and Kyoto Encyclopedia of Genes and Genomes pathways. The web server can be used to infer functions and putative phenotypes of a gene along with the candidate genes of a phenotype, and thus aids in disease candidate gene discovery. Our web server is available at http://jjwanglab.org/PhenoPPIOrth.  相似文献   
9.
本研究利用生物信息学分析AP-4与胃癌患者临床病理信息的相关性,根据GenBank中人AP-4基因cDNA序列设计并合成特异性引物,以胃癌细胞总RNA逆转录的cDNA为模板,利用高保真酶扩增AP-4基因CDS (Coding DNA sequence)序列并构建入pcDNA3.1+载体,并通过限制性内切酶酶切分析和测序法进行进一步验证;脂质体法将AP-4重组表达载体及对照pcDNA3.1+载体转染胃癌细胞,qRT-PCR(Quantitative real time polymerase chain reaction)和Western blotting检测分别检测AP-4在m RNA和蛋白水平的表达。生物信息学分析发现,AP-4的表达与胃癌分期及预后显著相关;酶切及测序分析表明,转录因子AP-4真核表达载体构建成功,并能够在胃癌细胞中实现转录和蛋白水平的高效表达。此研究为深入研究转录因子AP-4在胃癌等肿瘤发生发展中的作用及分子机制奠定了基础。  相似文献   
10.
A new strategy for realizing ultra-narrowband plasmonic absorber has been theoretically demonstrated. Dual-band perfect light absorber with the bandwidth down to single digit level and the maximal absorption exceeding 99.2 % is achieved. Moreover, novel absorber-based sensor platform with high-quality factors (S?>?420 nm/RIU, FOM?>?84, and FOM*?>?5600) are obtained. These features hold the proposed absorber to be a feasible candidate for applications in the sensing detection and notch filtering.  相似文献   
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