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排序方式: 共有685条查询结果,搜索用时 15 毫秒
1.
Ai-Jie Xin Li Cheng Hua Diao Peng Wang Yi-Hua Gu Bin Wu Yan-Cheng Wu Guo-Wu Chen Shu-Min Zhou Shu-Juan Guo Hui-Juan Shi Sheng-Ce Tao 《Clinical proteomics》2014,11(1):10
It is well known that cell surface glycans or glycocalyx play important roles in sperm motility, maturation and fertilization. A comprehensive profile of the sperm surface glycans will greatly facilitate both basic research (sperm glycobiology) and clinical studies, such as diagnostics of infertility. As a group of natural glycan binders, lectin is an ideal tool for cell surface glycan profiling. However, because of the lack of effective technology, only a few lectins have been tested for lectin-sperm binding profiles. To address this challenge, we have developed a procedure for high-throughput probing of mammalian sperm with 91 lectins on lectin microarrays. Normal sperm from human, boar, bull, goat and rabbit were collected and analyzed on the lectin microarrays. Positive bindings of a set of ~50 lectins were observed for all the sperm of 5 species, which indicated a wide range of glycans are on the surface of mammalian sperm. Species specific lectin bindings were also observed. Clustering analysis revealed that the distances of the five species according to the lectin binding profiles are consistent with that of the genome sequence based phylogenetic tree except for rabbit. The procedure that we established in this study could be generally applicable for sperm from other species or defect sperm from the same species. We believe the lectin binding profiles of the mammalian sperm that we established in this study are valuable for both basic research and clinical studies. 相似文献
2.
Fuxin Zhao Jinyu Wu Anquan Xue Yanfeng Su Xiaojing Wang Xianmin Lu Zhonglou Zhou Jia Qu Xiangtian Zhou 《Human genetics》2013,132(8):913-921
Myopia is a refractive error of the eye that is prevalent worldwide. The most extreme form, high myopia, is usually associated with other ocular disorders such as retinal detachment, macular degeneration, cataract, and glaucoma, and is one of leading causes of blindness. The etiology is complex and has not been fully elucidated. In this study, we identified a novel missense variant of the CCDC111 gene (NM_152683.2: c.265T > G; p.Y89D) in a high myopia family by exome sequencing. The variant was identified in 4 patients from an additional 270 sporadic high myopia patients, but not found in 270 controls. The amino acid is highly conserved across species, and variants giving rise to amino acid substitutions are predicted to be functionally damaging. The CCDC111 gene was ubiquitously expressed in primary cell cultures from human eye tissue, including corneal epithelial cells, choroidal melanoma cells, scleral fibroblasts, retinal epithelial cells, retinal Müller cells, and lens capsule epithelial cells. In summary, our results suggested that the CCDC111 may be a susceptibility gene for high myopia. 相似文献
3.
Xiao-Zhi Yang Xiao-Juan Diao Wen-Hui Yang Feng Li Guang-Wei He Guo-Qing Gong Yun-Gen Xu 《Bioorganic & medicinal chemistry letters》2013,23(7):2089-2092
A novel series of prodrugs containing dabigatran and methyl (E)-3-(4-hydroxy-2-methoxyphenyl)propenoate (methyl ferulate) were synthesized. All of them reveal the effect of thrombin-induced anti-platelet aggregation in vitro. In addition, in vivo experiment shows that one of the target compounds, X-2 (ED50 = 3.7 ± 1.0 μmol/kg) possesses a more potent activity for inhibiting venous thrombosis than that of dabigatran etexilate (ED50 = 7.8 ± 1.5 μmol/kg). 相似文献
4.
Parkinson disease (PD) is the second most common neurodegenerative disorder after Alzheimer's disease, affecting 1–2% of the population over the age of 65. Both genetic and environmental factors trigger risks of and protection from PD. However, the molecular mechanism of PD is far from being clear. In this study, we downloaded the gene expression profile of PD from Gene Expression Omnibus and identified differentially expressed genes (DEGs) and dysfunctional pathways in PD patients compared with controls. To further understand how these pathways act together to account for the initiation of PD, we constructed a pathway crosstalk network by calculating the Jaccard index among pathways. A total of 873 DEGs and 16 dysfunctional pathways between PD patients and controls were identified. Through constructing a network of pathways, the relationships among PD pathways were visually presented by their interactions. Our results demonstrate the existence of crosstalk between different pathways in PD pathogenesis. These results not only may explain the causes of PD, but could also open the door to new therapeutic approaches for this disease. 相似文献
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6.
Xianwen Cao Jing Jiang Shoude Zhang Lili Zhu Juan Zou Yanyan Diao Weilie Xiao Lei Shan Handong Sun Weidong Zhang Jin Huang Honglin Li 《Bioorganic & medicinal chemistry letters》2013,23(11):3329-3333
Eleven compounds were identified as estrogen receptor modulators from an in-house natural product database (NPD) by structure-based virtual screening for ERα and ERβ. Among them, 3 compounds were confirmed as ER agonists and 8 compounds were confirmed as ER antagonists by yeast two-hybrid (Y2H) assay, with EC50 values ranging from several micromolar to 100 micromolar. In this study, a novel series of cycloartane triterpenoids isolated from Schisandra glaucescens Diels was found to have ER antagonistic effect, the most potent antagonist of which exhibited activity with EC50 value of 2.55 and 4.68 μM for ERα and ERβ, respectively. Moreover, the types of modulation and subtype selectivity were also investigated through molecular docking simulation. 相似文献
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8.
Background
Infantile hemangioma (IH) is a benign vascular neoplasm that arises from the abnormal proliferation of endothelial cells and enhanced angiogenesis. Recently, propranolol has been found to be effective in the management of IH, suggesting that β-adrenergic receptors (β-ARs) may play an important role in the pathogenesis of IH.Results
In the present study, we investigated the β-adrenergic signaling that is associated with hemangioma-derived endothelial cell (HemEC) proliferation. The results showed that both β1- and β2-ARs were expressed in HemECs. Stimulation of the β-ARs by isoprenaline induced cell proliferation and elevation of second messenger cAMP levels. The proliferation-promoting action of isoprenaline was abolished by a β1-selective antagonist and was more effectively abolished by a β2-selective antagonist; the mechanism for the action of the antagonists was a G0/G1 phase cell cycle arrest which was associated with decreased cyclin D1, CDK-4, CDK-6 and phospho-Rb expression. Pre-treatment of the cells with VEGFR-2 or ERK inhibitors also prevented the isoprenaline-mediated proliferation of cells. In agreement with the involvement of β-ARs and VEGFR-2 in the HemEC response, β-AR antagonists and the VEGFR-2 inhibitor significantly attenuated isoprenaline-induced ERK phosphorylation. Moreover, treating the cells with isoprenaline markedly increased VEGF-A expression and VEGFR-2 activity in a β2-AR-dependent manner.Conclusions
We have demonstrated that the activation of the β-ARs in the ERK pathway may be important mechanisms in promoting HemEC growth. Furthermore, stimulation of the β-AR may transactivate VEGFR-2 signaling and further increase HemEC proliferation. 相似文献9.
Lianzheng Yu Chao Jiang Jun Na Ning Li Wenli Diao Yuan Gu Li Zhao Yan Zou Ying Chen Li Liu Huijuan Mu Yunyong Liu Liya Yu Xiaoli Yang Guowei Pan 《PloS one》2013,8(4)
Background
This study aimed to assess whether Chinese men who have sex with men (MSM) had a significantly elevated prevalence of psychiatric disorders compared to urban males in China.Methods
807 MSM were recruited using a respondent-driven sampling (RDS) method in urban area of northeast China. Psychiatric disorders were assessed employing the Composite International Diagnostic Interview (CIDI. Version 1.0) according to the criteria of the DSM-III-R.Results
Chinese MSM had a significantly elevated standardized prevalence ratios (SPR) for lifetime prevalence of any disorder (SPR = 2.8; 95%CI: 2.5–3.2), mood disorder (SPR = 3.0; 95%CI: 2.3–3.7), anxiety disorder (SPR = 5.5; 95% CI: 4.6–6.5), alcohol use disorder (SPR = 2.4, 95%CI: 2.0–2.8), and combination of disorders (SPR = 4.2; 95%CI: 3.4–5.1).Conclusions
Chinese MSM had significantly elevated prevalence and comorbidity of psychiatric disorders. RDS is a suitable sampling method for psychiatric epidemiological survey in MSM population. 相似文献10.
Nan Jiang Cheng-he Qin Cai-xia Tan Shi-feng Wen Yun-fei Ma Fu Dong Xi-cai Diao Peng Zhang Bin Yu 《Cancer epidemiology》2013,37(3):294-299
Background: Update reports are rarely available regarding the bone giant cell tumors (GCTs) in the extremity in Chinese people. The aim of this study was to review the epidemiological characteristics of bone GCT in the extremity based on the clinical data from four hospitals in South China. Methods: We searched medical electronic records from January 2001 to December 2011 in four hospitals in South China to identify patients with definite diagnosis of extremity GCT. Epidemiological data including gender, tumor site, age at the time of first diagnosis, local recurrence and pulmonary metastasis were collected and analyzed statistically. Differences between-genders were particularly analyzed regarding first diagnosis age, tumor site, local recurrence and pulmonary metastasis. T-test and Chi-square test were used for continuous and dichotomous variables, respectively. Results: A total of 140 GCT patients (87 males and 53 females) were identified. The gender ratio was 1.64 for a male predominance. GCTs were mostly located around the knee (67 cases). 92 patients were in their 20s to 40s upon first diagnosis. The average age at the time of first diagnosis for all was 30.49 years, 30.76 years for males and 30.06 years for females (P = 0.757). GCT recurred locally in 50 patients (26 males and 24 females) with no gender difference (P = 0.065). The average interval from first surgery to local recurrence was 21.42 months. Pulmonary metastasis was found in 11 patients (8 males and 3 females) also with no gender difference (P = 0.667). The average interval from first diagnosis to metastasis was 36.45 months. Conclusions: Extremity GCT may have a male predominance in Chinese population and mostly occur at 20–40 years of age and around the knee. Follow-ups for GCT patients should be carried on for at least 3 years after primary surgery according to the average intervals for possible local recurrence and pulmonary metastasis. 相似文献