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61.
双眼和单眼视觉剥夺猫外膝体细胞的图形适应 总被引:1,自引:0,他引:1
为测定丘脑外膝体细胞的图形适应是否依赖于早期视觉经验,在细胞外记录了双眼和单眼缝合的猫外膝体中断细胞对手工时间运动光栅刺激的反应。在双眼剥夺猫,占68%的记录到的细胞在30s内反应下降到稳定值,其平均反应值下降33%,适应程度较正常猫显著。在单眼剥夺猫,记录到的剥夺眼驱动的和非剥夺眼驱动的细胞中,分别有占53%和44%的细胞显示图形适应,两者差别不大。研究表明,早期视剥夺能增强或保持图形适应,提示 相似文献
62.
用脑光学成像术研究不同空间拓扑位置猫初级视皮层的空间频率反应特性 总被引:4,自引:1,他引:3
采用基于内源信号的脑光学成像方法,在大范围视皮层研究了不同空间拓扑位置对应的皮层区的对光栅刺激空间频率反应特性。结果表明,周边视野对应区对高空间频率刺激反应极弱或没有反应,中心视野对应区对较宽的空间频率范围内的刺激均有反应,但对高频刺激反应更强;无论在周边对应区还是中心对应区,其视野越靠近中心,其空间频率调谐曲线和截止空间频率越靠近高频,而且这种过渡是平缓的。以上结果说明,猫初级视皮层空间频率反应 相似文献
63.
64.
17个新的C2H2型锌指基因片段的分离与克隆 总被引:4,自引:0,他引:4
按照C2H2型锌指基因保守结构域的DNA序列设计一对简并引物,以人基因组DNA为模板进行PCR同源扩增,将由此获得的锌指基因片段为探针,从人胎肾、骨骼肌、骨骼组织的cDNA分子库中筛选到22个C2H2型锌指蛋白cDNA片段,经国际NCBI数据库查询检索,其中17个为新的锌指基因片段。对从胎肾cDNA分子库中分离到的K3-4和K5-12克隆进行了表达谱分析,发现K3-4在肾脏中的表达量明显高于其他几 相似文献
65.
Yu‐Kuang Liao Maël Brossard Dan‐Hua Hsieh Tzu‐Neng Lin Martin D. B. Charlton Shun‐Jen Cheng Chyong‐Hua Chen Ji‐Lin Shen Lung‐Teng Cheng Tung‐Po Hsieh Fang‐I Lai Shou‐Yi Kuo Hao‐Chung Kuo Pavlos G. Savvidis Pavlos G. Lagoudakis 《Liver Transplantation》2015,5(2)
A novel scheme for hybridizing inkjet‐printed thin film Cu(In,Ga)Se2 (CIGS) solar cells with self‐assembled clusters of nanocrystal quantum dots (NQDs), which provides a 10.9% relative enhancement of the photon conversion efficiency (PCE), is demonstrated. A non‐uniform layer of NQD aggregates is deposited between the transparent conductive oxide and a CdS/CIGS p‐n junction using low cost pulsed‐spray deposition. Hybridization significantly improves the external quantum efficiency of the hybrid devices in the absorption range of the NQDs and in the red to near‐IR parts of the spectrum. The low wavelength response enhancement is found to be induced by luminescent down‐shifting (LDS) from the NQD layer, while the increase at longer wavelengths is attributed to internal scattering from NQD aggregates. LDS is demonstrated using time‐resolved spectroscopy, and the morphology of the NQD layer is investigated in fluorescence microscopy and cross‐sectional transmission electron microscopy. The influence of the NQD dose on the PCE of the hybrid devices is investigated and an optimum value is obtained. The low costs and limited material consumptions associated with pulsed‐spray deposition make these flexible hybrid devices promising candidates to help push thin‐film photovoltaic technology towards grid parity. 相似文献
66.
Tiantian She Chuanke Zhao Junnan Feng Lixin Wang Like Qu Ke Fang Shaoqing Cai Chengchao Shou 《PloS one》2015,10(3)
Sarsaparilla, also known as Smilax Glabra Rhizome (SGR), was shown to modulate immunity, protect against liver injury, lower blood glucose and suppress cancer. However, its effects on cancer cell adhesion, migration and invasion were unclear. In the present study, we found that the supernatant of water-soluble extract from SGR (SW) could promote adhesion, inhibit migration and invasion of HepG2, MDA-MB-231 and T24 cells in vitro, as well as suppress metastasis of MDA-MB-231 cells in vivo. Results of F-actin and vinculin dual staining showed the enhanced focal adhesion in SW-treated cells. Microarray analysis indicated a repression of TGF-β1 signaling by SW treatment, which was verified by real-time RT-PCR of TGF-β1-related genes and immunoblotting of TGFBR1 protein. SW was also shown to antagonize TGF-β1-promoted cell migration. Collectively, our study revealed a new antitumor function of Sarsaparilla in counteracting invasiveness of a subset of cancer cells by inhibiting TGF-β1 signaling. 相似文献
67.
Xiaoming Zhu Yongfei Wang Xuelan Zhao Cuiping Jiang Qiongyue Zhang Wenjuan Jiang Yan Wang Haixia Chen Xuefei Shou Yao Zhao Yiming Li Shiqi Li Hongying Ye 《PloS one》2015,10(9)
Background
There are few studies of the incidence and clinical characteristics of pituitary apoplexy (PA) in pituitary adenoma patients, and the findings have been inconsistent.Objective
The aim of the study was to retrospectively assess the incidence, clinical presentation, surgical management and postoperative complications of PA in pituitary adenoma patients.Methods
A database was specifically designed to collect clinical, therapeutic, prognostic and histological information about pituitary adenoma patients. Using multivariate logistic regression, odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to identify associated factors.Results
A total of 2021 pituitary adenoma patients were recruited. 97 (4.8%) patients had PA. The incidence of PA was 10.11% in patients with pituitary macroadenoma, and 0.36% in patients with microadenoma. Variables for the logistic regression model independently associated with PA were sex (male vs. female, OR = 2.54, 95% CI: 1.59~4.07), tumor type (negative staining vs. positive staining, OR = 2.04, 95% CI: 1.29~3.23), and tumor size (macroadenoma vs. microadenoma, OR = 26.46, 95% CI = 9.66~72.46). Headache, visual deterioration, and vomiting were the most common symptoms in patients with pituitary adenoma. Patients with and without PA had similar frequency of visual deterioration, head trauma, acromegalic appearance, galactorrhoea, cold intolerance and Cushingoid appearance, but headache, vomiting, ptosis, diplopia, fever and blindness were significantly more common in patients with PA. Pearson Chi-Square tests revealed a significant difference in surgical approach between patients with and without PA (95.88% vs. 85.57%, P = 0.01).Conclusion
Our findings suggest that PA is not a rare event. Male sex, non-functioning tumor, and macroadenoma are associated with an increased risk of PA. Compared with pituitary adenoma patients without PA, patients with PA have more severe symptoms. 相似文献68.
69.
70.
Shou‐Hsien Li Carol K.‐L. Yeung Lianxian Han Manh Hung Le Chi‐xan Wang Ping Ding Cheng‐te Yao 《Journal of avian biology》2010,41(1):64-73
Identification of interspecific hybrids is often a subject of primary concern in the development of conservation strategies. Here we performed a genetic analysis combining mitochondrial DNA (mtDNA), microsatellites and single nucleotide polymorphic sites (SNPs) to assay the level of hybridization and introgression between an introduced babbler, Chinese hwamei Leucodioptron canorus, and its close relative, the endemic Taiwan hwamei L. taewanus in Taiwan. Fifty‐five Chinese hwameis from the Asian mainland and 69 Taiwan hwameis, including nine morphological hybrids, were sampled and analyzed. Evidences of mitochondrial introgression were found in three hybrids and one Taiwan hwamei. Five unlinked interspecific SNPs were identified at nine anonymous nuclear loci with interspecific differentiation (total Fst=0.77) that was much higher than that at seven highly polymorphic microsatellite loci combined (total Fst=0.1). Bayesian cluster analysis based on five interspecific SNP loci and two highly differentiated microsatellite loci (Fst>0.08) suggested that twelve individuals sampled in Taiwan were likely F2 or backcross hybrids, among which eight were morphological intermediates. A total of 20.3% (14/69) individuals sampled in Taiwan were suggested to be hybrids, suggesting that fitness reduction in hybrids might be negligible. These results imply that without an effective management strategy, the entire Taiwan hwamei population could easily become an admixed with Chinese hwamei and loose its evolutionary integrity. To reduce introgressive hybridization, illegal trade of Chinese hwamei should be strictly regulated and only the expensive male Chinese hwameis should be legally imported to minimize the chance for Chinese hwameis being released into the field. In our study we also found interspecific SNP markers to outperform microsatellite loci in detecting hybridization and introgression between two closely related species, which may be ascribed to the lower level of homoplasy of SNP loci. 相似文献