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81.
Bayer M Fischer J Kremerskothen J Ossendorf E Matanis T Konczal M Weide T Barnekow A 《BMC cell biology》2005,6(1):15
Background
The small GTPase rab1a and its isoform rab1b are essential regulating components in the vesicle transport between the ER and the Golgi apparatus. Rab1 is thought to act as a molecular switch and can change between an active GTP-bound and an inactive GDP-bound conformation. To elucidate the function of rab1, several approaches have been established to isolate effector proteins, which interact with the activated conformation of rab1. To date p115, GM130, golgin-84 and MICAL have been identified as direct interacting partners. Together with rab1, these molecules are components of a protein complex, which mediates and regulates intracellular vesicle transport. 相似文献82.
Evangelos?G?PapanikolaouEmail author Nikos?Plachouras Aikaterini?Drougia Styliani?Andronikou Christina?Vlachou Theodoros?Stefos Evangelos?Paraskevaidis Konstantinos?Zikopoulos 《Reproductive biology and endocrinology : RB&E》2004,2(1):70
Background
The objective of this randomized prospective study was to compare the efficacy of 50 mcg vaginal misoprostol and 3 mg dinoprostone, administered every nine hours for a maximum of three doses, for elective induction of labor in a specific cohort of nulliparous women with an unfavorable cervix and more than 40 weeks of gestation. 相似文献83.
Theodoros Giannakopoulos 《PloS one》2015,10(12)
Audio information plays a rather important role in the increasing digital content that is available today, resulting in a need for methodologies that automatically analyze such content: audio event recognition for home automations and surveillance systems, speech recognition, music information retrieval, multimodal analysis (e.g. audio-visual analysis of online videos for content-based recommendation), etc. This paper presents pyAudioAnalysis, an open-source Python library that provides a wide range of audio analysis procedures including: feature extraction, classification of audio signals, supervised and unsupervised segmentation and content visualization. pyAudioAnalysis is licensed under the Apache License and is available at GitHub (https://github.com/tyiannak/pyAudioAnalysis/). Here we present the theoretical background behind the wide range of the implemented methodologies, along with evaluation metrics for some of the methods. pyAudioAnalysis has been already used in several audio analysis research applications: smart-home functionalities through audio event detection, speech emotion recognition, depression classification based on audio-visual features, music segmentation, multimodal content-based movie recommendation and health applications (e.g. monitoring eating habits). The feedback provided from all these particular audio applications has led to practical enhancement of the library. 相似文献
84.
The focal adhesion, the actin cytoskeleton and cell-cycle are connected pathways and their genes are implicated in the pathogenesis of low BMD. Data from 211 studies that investigated the association between BMD and gene variants involved in these pathways were catalogued in a web-based information system and analyzed. In individual studies, significant association was found for 16 variants in lumbar spine, 11 in femoral neck and 5 in hip. In meta-analysis, significant results were shown for the variants COL1A1 rs1800012 (in lumbar spine and femoral neck), COL1A1 rs1107946 (in lumbar spine), TGFB1 rs1982073 (in femoral neck and hip) and TGFB1 rs1800469 (in lumbar spine). 相似文献
85.
86.
Athanasios Charalampopoulos Athanasios Damialis Ioannis Tsiripidis Theodoros Mavrommatis John M. Halley Despoina Vokou 《Aerobiologia》2013,29(4):455-472
We studied airborne pollen along an elevation gradient of Mt Olympos (Greece). Samples were collected on a regular basis, over the period March–October 2009, in eight elevation-different stations, by use of a portable Hirst-type volumetric sampler. Concurrently, we studied pollen production in Quercus coccifera, Q. ilex, Pinus heldreichii and P. nigra, which are dominant species in the main vegetation types of the mountain. Of the 35 pollen taxa detected in the air, 18 account for 99.1 % of the total airborne pollen. These are the main pollen taxa each contributing by at least 0.5 %. Pinaceae (32 %) followed by Quercus (24 %) and Urticaceae (18 %) are the most abundantly represented taxa. Duration of the pollen season decreases with elevation by on average 3 days for every 100 m of elevation increase or by 5 days for every Celsius-degree of temperature decrease. Pollen concentration in the air decreases with elevation for the lowland taxa; with the exception of Cupressaceae, no pattern is observed for the other main taxa. The pine and oak species studied carry comparable amounts of pollen, approximately 104 grains per flower, 108–109 per m2 of crown surface and 1010–1011 per individual; pollen production, primarily of the two Quercus species, is not responsive to environmental changes associated with elevation. Results provide evidence that, within a margin of error, airborne pollen reflects the distributions of pollen taxa on the mountain; regarding abundance, airborne pollen is representative of Quercus, but under-representative of Pinaceae. Ambrosia pollen is found at all elevations examined, although plants producing it have not been recorded on or around Mt Olympos. 相似文献
87.
Ioannis Protopsaltis Achilles Ploumidis Theodoros N. Sergentanis Padelis Constantoulakis Kostantinos Tzirogiannis Chrysoula Kyprianidou Athanasia K. Papazafiropoulou Andreas Melidonis Dimitrios Delakas 《PloS one》2013,8(12)
Benign prostatic hyperplasia (BPH) represents a pattern of non-malignant growth of prostatic fibromuscular stroma. Metabolic disturbances such us pre-diabetes and metabolic syndrome may have a role in BPH pathophysiology. A potential explanation for the above relationship involves the insulin-like growth factor (IGF) axis as well as IGF binding proteins, (IGFBPs) of which the most abundant form is IGFBP-3. Therefore, the aim of the present study was to investigate the association between intra-prostatic levels of IGF-1, IGF-2 as well as to evaluate the role of locally expressed IGFBP-3 in BPH development in pre-diabetes. A total of 49 patients admitted to the Urology department of a tertiary urban Greek hospital, for transurethral prostate resection, or prostatectomy and with pre-diabetes [impaired fasting glucose (IFG) and impaired glucose tolerance (IGT) or both] were finally included. The majority of the sample consisted of subjects with IGT (51.0%), followed by IFG and IGT (32.7%) and isolated IFG (16.3%). For all participants a clinical examination was performed and blood samples were collected. In addition, total prostate (TP) volume or transitional zone (TZ) volume were estimated by transrectal ultrasonography. The results of the multivariate analysis regarding TP volume showed that higher PSA (p<0.001), larger waist circumference (p=0.007) and higher IGFBP-3 expression levels (p<0.001) independently predicted higher TP volume. The results regarding the volume of the TZ showed that higher PSA (p<0.001), larger waist circumference (p<0.001) and higher IGFBP-3 expression levels (p=0.024) were independently associated with higher TZ volume. Our findings show that intra-prostatic levels of IGFBP-3, PSA and waist circumference, but not overall obesity, are positively associated with prostate volume. IGFBP-3 seems to be a multifunctional protein, which can potentiate or inhibit IGF activity. 相似文献
88.
Cyclin D1 represents a key molecule in the regulation of cell cycle. CCND1 G870A (rs603965) polymorphism has drawn considerable
attention as the A allele may generate a variant splice product with possible oncogenic actions. A meta-analysis examining
the association between CCND1 G870A polymorphism and breast cancer risk was performed. Separate analyses on Caucasian and
Chinese populations were also implemented. Eligible articles were identified for the period up to July 2010. Pooled odds ratios
(OR) were appropriately derived from fixed-effects or random-effects models. Sensitivity analysis excluding studies whose
genotype frequencies in controls significantly deviated from Hardy–Weinberg Equilibrium (HWE) was performed. Nine case–control
studies on Caucasians (7,304 cases and 8,149 controls) and four case–control studies on Chinese (2,607 cases and 3,022 controls)
were eligible. At the overall analysis the A allele seemed to be associated with elevated breast cancer risk; the effect seemed
to be confined to homozygous carriers (pooled OR = 1.091, 95% CI: 1.008–1.179, P = 0.030, fixed effects) as heterozygous carriers did not exhibit significantly elevated breast cancer risk. No statistically
significant associations were demonstrated in Caucasians. On the other hand, Chinese AA carriers exhibited marginally elevated
breast cancer risk (pooled OR = 1.144, 95% CI: 0.984–1.329, P = 0.080, fixed effects). Nevertheless, the controls in two out of the four Chinese studies deviated from HWE. In conclusion,
this meta-analysis suggests that the A allele of the CCND1 G870A polymorphism may confer additional breast cancer risk when
it comes to homozygosity and Chinese populations. The need for additional, methodologically sound studies on Chinese populations
seems warranted. 相似文献
89.
Menzel U Kosteas T Tolaini M Killeen N Roderick K Kioussis D 《Journal of immunology (Baltimore, Md. : 1950)》2011,187(7):3712-3720
The human CD2 (hCD2) locus control region (LCR) inserted in the mouse CD8 gene complex activates expression of the CD8 genes in T cell subsets in which the CD8 locus is normally silenced (e.g., CD4(+) single-positive T cells). In this article, we show that, in conditional mCD8/hCD2-LCR (CD8/LCR) knock-in mice, the continuous presence of the hCD2-LCR is required for this effect. Deletion of the inserted hCD2-LCR in a developmental stage and cell lineage-specific manner revealed that the temporary presence of the LCR during early development does not permanently alter the expression pattern of the CD8 genes. As a result, cells that have been affected by the insertion of the LCR can convert to their destined phenotype once the LCR is removed. DNaseI hypersensitive sites 1 and 2 of the hCD2-LCR influence the expression of the CD8 genes in a similar manner as does the full LCR, whereas insertion of hypersensitive site 3 alone of the LCR does not result in a changed expression pattern. This analysis revealed a dynamic interaction between the hCD2-LCR and the endogenous regulatory elements of the CD8 genes. 相似文献
90.