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41.

Purpose

To investigate the predictors and treatment of the 6-Fr Perclose Proglide-related complications (PRC) in percutaneous endovascular aortic repair (pEVAR).

Methods

We retrospectively analyzed the PRC after pEVAR for the treatment of aortic aneurysm or dissection in our center from December 2012 to November 2013. Procedure success was defined as effective functioning of the two devices and local hemostasis. Access-related adverse events included vascular complications and device failures. Operative data and angiographic and computed tomography images were collected to assess the complications and treatment strategy.

Results

A total of 198 patients with 275 puncture sites underwent pEVAR with the 6-Fr Perclose Proglide. The procedure was successful in 178 patients (89.9%), whereas PRC occurred in 20 cases (10.1%), including 10 device failures and 10 vascular complications. An extra manual ancillary compression was conducted in 7 patients, one more device was used in 8 patients, and surgical repair of the femoral artery was performed in 5 patients. PRC had a tendency to occur in patients with body mass index (BMI)>30 kg/m2 (p = 0.021), thoracic stent grafts (p = 0.038), common femoral artery (CFA) calcification (p = 0.001), CFA depth>4 cm (p = 0.001), and sheath size>20Fr (p = 0.005). Device failure-related mortality was zero. None of the access sites had complications during the midterm follow-up.

Conclusions

The pre-close technique with 6-Fr Perclose Proglide devices for pEVAR appears to be safe and effective with low technical failure and complication rates. Careful patient selection and proficiency in device manipulation might reduce the device related complications.  相似文献   
42.
The analysis of woody plant leafing in response to regional-scale temperature variation using ground-based phenology is usually limited by the sparse coverage and missing data of ground observation. In this study, a station-based multispecies method was proposed to generate spatiotemporal variation of woody plant leafing date using ground observations from the Chinese Phenological Observation Network during 1974–1996. The results show that the leafing date had slightly insignificant advance (?0.56 day decade?1), and the Arctic Oscillation (AO) index could explain 36 % variance of the spring leafing date anomaly. The leafing date had been substantially delayed (4 days) when AO shifted from an extreme high index state (2) in 1989–1990 to a relatively low state (0.1) in 1991–1996. The canonical correlation analysis (CCA) was used to demonstrate the temporal evolutions and spatial structures of interannual variations of the spring temperature and leafing date anomalies. The three CCA spatial patterns of leafing date anomaly are similar to those of spring temperature anomaly. The first spatial pattern shows ubiquitous warming, which is consistent with the ubiquitous advance in leafing date across the study area. The second and third spatial patterns present the regional differences featured by advanced (delayed) leafing associated with high (low) temperature. The results suggest that the spring leafing date anomaly is spatiotemporally coherent with the regional-scale temperature variations. Although we focus here on woody plant leafing in a historical period in temperate eastern China, our station-based multispecies method may be applicable to analysis of the ground-based phenology in response to regional-scale climatic variation in other regions.  相似文献   
43.
LIM mineralization protein 1 (LMP-1) is an essential positive regulator of osteoblast differentiation, maturation and bone formation. Our previous investigations on the distribution of LMP-1 in mature human teeth indicated that LMP-1 might play a role in the odontoblast differentiation and dentin matrix mineralization. The aim of the present study was to use immunohistochemistry to determine the expression of LMP-1 during tooth development in mouse molars. In embryonic and postnatal Kunming mice, LMP-1 protein was expressed during molar development, but the expression levels and patterns differed at various developmental stages. At embryonic day 13.5 (E13.5), LMP-1 was found in the enamel organ. At E14.5, LMP-1 was detected in the entire enamel organ and in the underlying mesenchyme. At E16.5, LMP-1 was observed in the inner and outer enamel epithelium and the stratum intermedium. The expression also converged at the cusps in the dental papilla. At E18.5 and postnatal day 2.5 (P2.5), LMP-1 was restricted to the stratum intermedium, in differentiating dental papilla cells at cusps, while it disappeared in terminal differentiated ameloblasts and odontoblasts. At P13.5, no positive staining was detected in the odontoblasts or in the dental pulp cells. Therefore, LMP-1 showed spatiotemporal expression patterns during molar development and might participate in molar crown morphogenesis and odontoblast differentiation at late molar development.  相似文献   
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45.
Isolating high-quality RNA from mangroves without liquid nitrogen   总被引:1,自引:0,他引:1  
Mangroves form unique communities in tropical coastal regions and tidal lowlands. Isolating RNA from mangrove leaves is difficult because of high amounts of secondary metabolites and polysaccharides. Conventional extraction methods produce poor-quality mangrove RNA. We present a simple, fast, and convenient protocol for isolating RNA from 5 mangrove species:Aegiceras corniculatum, Bruguiera gymnorrhiza, Ceriops tagal, Kandelia candel, andSonneratia apetala. Isolating RNA from other mangrove species is also possible. Obtained RNA was of high quality and used in an RT-PCR reaction that amplified 0.6 kb of theA. corniculatum CPI-1 gene.  相似文献   
46.
松材线虫伴生细菌多样性的宏基组分析   总被引:2,自引:0,他引:2  
摘要:【目的】松材线虫是松材线虫病的病原,且与其伴生细菌之间存在互作关系,它们构成一个微生态系统。本研究旨在揭示松材线虫-伴生细菌群落细菌多样性。【方法】采用16S rRNA基因文库和454测序对伴生细菌群落的宏基因组进行初步分析。【结果】依据97%序列相似性划分OTU(Operational Taxonomic Unit),构建的16S rRNA文库包含25个OTU,分别属于Alphaproteobacteria、Betaproteobacteria、Gammaproteobacteria和Bacter  相似文献   
47.
48.
49.
Hu B  Yang G  Zhao W  Zhang Y  Zhao J 《Molecular microbiology》2007,63(6):1640-1652
MreB is a bacterial actin that plays important roles in determination of cell shape and chromosome partitioning in Escherichia coli and Caulobacter crescentus. In this study, the mreB from the filamentous cyanobacterium Anabaena sp. PCC 7120 was inactivated. Although the mreB null mutant showed a drastic change in cell shape, its growth rate, cell division and the filament length were unaltered. Thus, MreB in Anabaena maintains cell shape but is not required for chromosome partitioning. The wild type and the mutant had eight and 10 copies of chromosomes per cell respectively. We demonstrated that DNA content in two daughter cells after cell division in both strains was not always identical. The ratios of DNA content in two daughter cells had a Gaussian distribution with a standard deviation much larger than a value expected if the DNA content in two daughter cells were identical, suggesting that chromosome partitioning is a random process. The multiple copies of chromosomes in cyanobacteria are likely required for chromosome random partitioning in cell division.  相似文献   
50.
Li  Wen  Liu  Juan  Ji  Li  Tang  Yi  Qin  Jianbing  Zhao  Heyan  Cheng  Xiang  Tian  Meiling  Jin  Guohua  He  Hui 《Neurochemical research》2022,47(3):679-691
Neurochemical Research - Glioma multiforme (GBM) is the most common malignant primary brain tumors. Despite the considerable advances in GBM treatment, it is still one of the most lethal forms of...  相似文献   
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