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Thick blood syndrome   总被引:1,自引:0,他引:1  
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204.
Haacke  EM; Bearden  FH; Clayton  JR; Linga  NR 《Radiology》1986,158(2):521-529
The time taken to collect high-resolution and high signal-to-noise (S/N) data in magnetic resonance (MR) imaging may be the limiting factor in patient throughput and in reducing patient motion. A hybrid fast-scan technique combining static and oscillatory phase-encoding gradients from two-dimensional Fourier transform (2DFT) and echo-planar imaging can reduce the time needed to collect data at the expense of loss in S/N. The flexibility of this technique is that any amplitude or frequency of oscillation of the phase-encoding gradient can be used. The technique was used for different frequencies and amplitudes, and images are presented that were acquired in one-half and one-quarter the time required with standard 2DFT techniques. The images illustrate that the hybrid and 2DFT techniques produce comparable resolution and contrast under identical conditions.  相似文献   
205.
Mice inoculated with ultraviolet light-inactivated Sendai virus mount a cell- mediated immune response to the virus. Cytotoxic T cells specific for Sendai virus can be obtained by in vitro secondary stimulation of primed spleen cells with syngeneic stimulator cells coated with UV-inactivated Sendai virus. Neither in vivo nor in vitro stimulation alone is sufficient to generate specific cytotoxic T cells. Sharing of the H-2 haplotype between cytotoxic T cells and target cells is required for the Sendai virus-specific lysis to occur. The fusion (F) glycoprotein of Sendai virus has been implicated in target antigen formation (20). Ethanol treatment of Sendai virus causes complete inactivation of the cell-fusion and hemolytic activities of the envelope, but does not affect the antigenicity of the F glycoprotein; furthermore, hemagglutinin and neuraminidase activities of the envelope HANA glycoprotein are also left intact after ethanol treatment. Target cells can be prepared by coating them with various numbers of UV-inactivated Sendai virus that have been treated with ethanol or, as a control, phosphate-buffered saline (PBS). The amount of virus adsorbed to target cells during the cytotoxicity reaction time using either ethanol-treated or untreated (PBS "treated") virions is essentially identical, but target cells coated with ethanol-treated Sendai virus fail to serve as targets for cytotoxic T cells. These results indicate that fusion activity of the Sendai virus envelope is essential to the formation of the target antigen and that virus adsorption to cell surfaces without fusion of the envelope with cell membranes is not sufficient to allow killing by virus-specific cytotoxic T cells.  相似文献   
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固相萃取GC-FID和GC-MS分析血浆中碱性药物   总被引:1,自引:0,他引:1  
报道了用X-5固相萃取分离、毛细管GC-FID和GC-MS定性定量分析人血浆中34种碱性药物的方法。在优化的提取条件下,大部分药物的最低检测浓度在0.5~2.0μg·ml-1之间,线性范围、定量精密度等满足临床中毒分析的要求。  相似文献   
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目的:在显微解剖学基础上,观察隐神经-大隐静脉营养血管远端蒂复合瓣移植修复小腿、踝足部创伤的临床效果。方法:选择2004-05/2007-04由解放军南京军区福州总医院骨科、解放军第97医院骨科、解放军第107医院骨科采用隐神经-大隐静脉营养血管远端蒂复合瓣移植修复小腿、踝足部组织缺损48例,患者对治疗均知情同意。其中皮瓣修复小腿、踝周及足部的创面感染、缺损23例;肌皮瓣修复小腿上段、下段的溃疡、骨髓炎和骨钢板外露12例,跟骨内侧骨髓炎5例;骨皮瓣修复伴有胫骨缺损和跟骨骨不连的创面8例。术后定期随访,观察隐神经-大隐静脉营养血管远端蒂皮瓣移植修复术后的存活情况及骨皮瓣的骨愈合、功能情况。结果:48例患者术后均有程度不同的皮瓣肿胀,其中3例皮瓣远侧边缘少量坏死,经换药愈合;皮瓣部分坏死植皮1例。伤口Ⅰ期愈合44例,Ⅱ期愈合4例。所有病例经5 ̄15个月随访,创面及骨不连修复,外形满意。结论:隐神经-大隐静脉营养血管远端蒂皮瓣、复合瓣用于外伤造成的小腿远端骨缺损、骨不连、大的死腔以及踝足部的缺损创面修复,具有快捷方便,抗感染力强,成活率高和愈合快的优点。  相似文献   
210.
Gastric cancer (GC) is the fourth most common cause of cancer-associated death. Based on the age at diagnosis, GC is divided into early-onset GC (EOGC; ≤45 years) and conventional GC (CGC; >45 years). Mutations in the cell cycle checkpoint kinase 2 (CHEK2) and TP53 genes are associated with several types of cancer; however, their genetic defects in GC remain poorly understood. The aim of the present study was to determine the subcellular distribution of the CHEK2 protein and its redistribution following DNA damage, to improve the understanding of the DNA damage response. Genetic alterations and patterns of expression of CHEK2 and p53 proteins were investigated to identify potential biological markers and indicators of GC development. Additionally, the affected signaling pathways and their clinical importance in GC development and associated syndromes were investigated. A total of 196 GC samples (89 CGC and 107 EOGC samples) were used in the present study. DNA from 53 samples (18 CGC and 35 EOGC samples) was sequenced using targeted next-generation sequencing technology to identify and compare common and rare mutations associated with GC. Subsequently, the cytoplasmic and nuclear expression levels of CHEK2, phosphorylated (p)-CHEK2 at threonine 68 and p53 in GC tissues were determined via immunohistochemistry. Sequencing resulted in the identification of 63 single nucleotide polymorphisms (SNPs) in the CHEK2 gene amongst 5 different variants, and the intron variant c.319+379A>G was the most common SNP. In the TP53 gene, 57 different alterations were detected amongst 9 variant types, and the missense variant c.215C>G was the most common. Nuclear CHEK2 expression was high in both the EOGC and CGC subtypes. However, the prevalence of cytoplasmic CHEK2 expression (P<0.001) and nuclear p-CHEK2 expression (P=0.011) was significantly higher in CGC compared with in EOGC tissues. There was a statistically significant difference between high and low cytoplasmic CHEK2 expression in patients with p53-positive EOGC compared with in patients with p53-positive CGC (P=0.002). The present study was designed to determine the association between CHEK2 and p53 expression patterns in patients with EOGC and CGC, as well as genetic alterations in the CHEK2 and TP53 genes.  相似文献   
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