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A detailed investigation of the impact of molecular weight distribution of a photoactive polymer, poly[N‐9′‐heptadecanyl‐2,7‐carbazole‐alt‐5,5‐(4′,7′‐di‐2‐thienyl‐2′,1′,3′‐benzothiadiazole)] (PCDTBT), on photovoltaic device performance and carrier transport properties is reported. It is found that different batches of as‐received polymers have substantial differences in their molecular weight distribution. As revealed by gel permeation chromatography (GPC), two peaks can generally be observed. One of the peaks corresponds to a high molecular weight component and the other peak corresponds to a low molecular weight component. Photovoltaic devices fabricated with a higher proportion of low molecular weight component have power conversion efficiencies (PCEs) reduced from 5.7% to 2.5%. The corresponding charge carrier mobility at the short‐circuit region is also significantly reduced from 2.7 × 10?5 to 1.6 × 10?8 cm2 V?1 s?1. The carrier transport properties of the polymers at various temperatures are further analyzed by the Gaussian disorder model (GDM). All polymers have similar energetic disorders. However, they appear to have significant differences in carrier hopping distances. This result provides insight into the origin of the molecular weight effect on carrier transport in polymeric semiconducting materials.  相似文献   
994.
Restenosis is one of clinical limitations for vein graft in coron- ary bypass graft. It has been proved that signal pathway IGF-1 and its receptor (IGF-1R) activated by hemodynamic mechanical stretch are responsible for the vascular smooth muscle cells proliferation in vein graft neointima formation. Unfortunately, there is no routinely successful method to resolve this problem. Gene delivering to vein graft possesses great therapeutic potential to prevent neointima formation. Polymer is one kind of nanoparticles, which can activate the process of endocytosis of cells. In this study, we evaluated the transfeetion efficiency and therapeutic potential of polymer- based transfection of plasmids expressing GFP and shRNAs targeting IGF-1R (pGFPshlGF-1Rs) to smooth muscle cells and rabbit external jugular vein graft. Results showed that polymer-based transfection provided high efficiency of trans- gene expression in smooth muscle cells in vitro. In vitro, IGF- 1R-specific shRNA transfected by polymer inhibited IGF-1R protein expression by 52 ±3.6%, when compared with mock transfected cells. In vivo delivering efficiency of pGFPshlGF-IR plasmid into the rabbit external jugular vein graft was significantly high in the polymer-based trans- fection group, when compared with negative control group. In vivo, polymer-based transfection IGF-1R-specific shRNA efficiently inhibited the expression of IGF-1R protein by 77 ± 3.6%, 65.6 ± 4.9%, and 76.7 ± 4.3% at 24, 48, and 72 h, respectively, when compared with negative control group. Our findings indicated that polymer-based transfec- tion may be a promising technique that allows the targeting of gene therapy for vein graft restenosis.  相似文献   
995.
Long noncoding RNAs (lncRNAs) play important roles in human diseases including vascular disease. Given the large number of lncRNAs, however, whether the majority of them are associated with vascular disease remains unknown. For this purpose, here we present a genomic location based bioinformatics method to predict the lncRNAs associated with vascular disease. We applied the presented method to globally screen the human lncRNAs potentially involved in vascular disease. As a result, we predicted 3043 putative vascular disease associated lncRNAs. To test the accuracy of the method, we selected 10 lncRNAs predicted to be implicated in proliferation and migration of vascular smooth muscle cells (VSMCs) for further experimental validation. The results confirmed that eight of the 10 lncRNAs (80%) are validated. This result suggests that the presented method has a reliable prediction performance. Finally, the presented bioinformatics method and the predicted vascular disease associated lncRNAs together may provide helps for not only better understanding of the roles of lncRNAs in vascular disease but also the identification of novel molecules for the diagnosis and therapy of vascular disease.  相似文献   
996.
The spike characteristics length, spikelet density and fertile floret number are related yield components and are important in cereal improvement. QSpl.nau-2D is a major quantitative trait locus controlling spike length (SPL) detected in the recombinant inbred line population developed by crossing wheat (Triticum aestivum) cultivars Nanda2419 with Wangshuibai. In this study, to validate its genetic effect and determine its precise location, QSpl.nau-2D’s near-isogenic line (NIL) was developed using Mianyang99-323 as the recurrent parent through marker-assisted selection. Field trials showed that the NIL not only had significantly longer spikes on average than the recurrent parent but also had significantly higher grain weight, but did not differ in spikelet number and kernel number per spike. In the F2 population derived from a cross of the NIL with Mianyang99-323, QSpl.nau-2D functioned like a single gene and conditioned the SPL in a partially dominant manner, and was thus designated as HL1 (for head length). To precisely map HL1, 89 recombinants, consisting of 11 genotypes, were identified in the NIL-derived F2 population of 674 plants by using markers in the Xwmc25Xgpw4080 interval. Phenotyping these lines showed that the introduction of a 0.9-cM interval flanked by Xcfd53 and DG371 in Nanda2419 resulted in longer spikes and a higher grain weight in the NIL. The availability of markers closely linked to HL1 could facilitate its use in breeding programs.  相似文献   
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998.
Micro/macrowire intracranial EEG (iEEG) signals recorded from implanted micro/macroelectrodes in epileptic patients have received great attention and are considered to include much information of neuron activities in seizure transition compared to scalp EEG from cortical electrodes. Microelectrode is contacted more close to neurons than macroelectrode and it is more sensitive to neuron activity changes than macroelectrode. Microwire iEEG recordings are inevitably advantageous over macrowire iEEG recordings to reveal neuronal mechanisms contributing to the generation of seizures. In this study, we investigate the seizure generation from microwire iEEG recordings and discuss synchronization of microwire iEEGs in four frequency bands: alpha (1−30 Hz), gamma (30−80 Hz), ripple (80–250 Hz), and fast ripple (>250 Hz) via two measures: correlation and phase synchrony. We find that an increase trend of correlation or phase synchrony exists before the macroseizure onset mostly in gamma and ripple bands where the duration of the preictal states varied in different seizures ranging up to a few seconds (minutes). This finding is contrast to the well-known result that a decrease of synchronization in macro domains exists before the macroseizure onset. The finding demonstrates that it is only when the seizure has recruited enough surrounding brain tissue does the signal become strong enough to be observed on the clinical macroelectrode and as a result support the hypothesis of progressive coalescence of microseizure domains. The potential ramifications of such an early detection of microscale seizure activity may open a new window on treatment by making possible disruption of seizure activity before it becomes fully established.  相似文献   
999.
Tumor immunosurveillance is known to be of critical importance in controlling tumorigenesis and progression in various cancers. The role of gamma-interferon-inducible lysosomal thiol reductase (GILT) in tumor immunosurveillance has recently been studied in several malignant diseases, but its role in breast cancer remains to be elucidated. In the present study, we found GILT as a significant different expressed gene by cDNA microarray analysis. To further determine the role of GILT in breast cancer, we examined GILT expression in breast cancers as well as noncancerous breast tissues by immunohistochemistry and real-time PCR, and assessed its association with clinicopathologic characteristics and patient outcome. The absence of GILT expression increased significantly from 2.02% (2/99) in noncancerous breast tissues to 15.6% (34/218) in breast cancer tissues (P<0.001). In accordance with its proliferation inhibiting function, GILT expression was inversely correlated with Ki67 index (P<0.05). In addition, absence of GILT was positively correlated with adverse characteristics of breast cancers, such as histological type, tumor size, lymph nodes status, and pTNM stage (P<0.05). Consistently, breast cancers with reduced GILT expression had poorer disease-free survival (P<0.005). Moreover, significantly decreased expression of GILT was found in both primary and metastatic breast cancer cells, in contrast to normal epithelial cells. These findings indicate that GILT may act as a tumor suppressor in breast cancer, in line with its previously suggested role in anti-tumor immunity. Thus, GILT has the potential to be a novel independent prognostic factor in breast cancer and further studies are needed to illustrate the underlying mechanism of this relationship.  相似文献   
1000.

Background

The Chinese population has undergone rapid transition to a high-fat diet. Furthermore, monosodium L-glutamate (MSG) is widely used as a daily food additive in China. Little information is available on the effects of oral MSG and dietary fat supplementation on the amino acid balance in tissues. The present study aimed to determine the effects of both dietary fat and MSG on amino acid metabolism in growing pigs, and to assess any possible interactions between these two nutrients.

Methods and Results

Four iso-nitrogenous and iso-caloric diets (basal diet, high fat diet, basal diet with 3% MSG and high fat diet with 3% MSG) were provided to growing pigs. The dietary supplementation with fat and MSG used alone and in combination were found to modify circulating and tissue amino acid pools in growing pigs. Both dietary fat and MSG modified the expression of gene related to amino acid transport in jejunum.

Conclusions

Both dietary fat and MSG clearly influenced amino acid content in tissues but in different ways. Both dietary fat and MSG enhance the absorption of amino acids in jejunum. However, there was little interaction between the effects of dietary fat and MSG.  相似文献   
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