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91.
目的:测量国人全膝关节假体置换术胫骨近端截骨面后缘至腘窝血管之间的距离,以期为临床全膝关节置换术中避免损伤腘窝血管提供参考数据。方法:选择2006-06/12于解放军第二军医大学长征医院体检的50名正常成人(53膝),男29名(31膝),女21名(22膝)。所有观察对象均知情同意,且得到医院伦理道德委员会批准。对所有膝关节进行MRI扫描,在胫骨外侧平台以下10mm水平横断面上辨认腘动静脉,并测量胫骨近端截骨面后缘至腘窝动静脉的距离。结果:53膝全部进入结果分析,无脱落。①男性胫骨近端截骨面后缘至腘动脉、腘静脉平均距离为(6.7±2.5,7.3±2.3)mm,95%可信区间分别为5.8~7.6mm,6.5~8.1mm。②女性胫骨近端截骨面后缘至腘动脉、腘静脉平均距离为(6.6±1.9,7.1±2.7)mm,95%可信区间分别为:5.8~7.4mm,5.9~8.3mm。③不同性别观察对象胫骨近端截骨面后缘至腘血管的距离差异无显著性意义(P>0.05)。结论:腘窝血管紧邻全膝关节假体置换术胫骨近端截骨面后缘,不同性别间无明显差异。全膝关节假体置换术中进行胫骨近端截骨,特别是后方操作时需特别谨慎,以避免损伤腘窝血管。  相似文献   
92.

Background

Hepatitis B immune globulins (HBIG) in combination with nucleos(t)ide analogues (NA) are effectively used for the prevention of hepatitis B virus (HBV) recurrence after liver transplantation (LT). However, associated treatment costs for HBIG are exceedingly high.

Methods

Fresh frozen plasma obtained from blood donors with high anti-HBs levels (hyperimmune plasma, HIP) containing at least 4,500 IU anti-HBs was used as alternative treatment for HBV recurrence prophylaxis post-LT.

Results

Twenty-one HBV-related LT recipients received HIP starting at transplantation, followed by long-term combination treatment with NA. Mean follow-up time was 4.5 years (range 0.5-12.6) and each patient received on average 8.2 HIP per year (range 5.8-11.4). Anti-HBs terminal elimination kinetic after HIP administration was 20.6 days (range 13.8-30.9), which is comparable to values reported for commercial HBIG products. All 21 patients remained free of HBV recurrence during follow-up and no transfusion-transmitted infection or other serious complication was observed. Seven patients developed reversible mild transfusion reactions. The cost for one HIP unit was US$140; average yearly HBIG treatment cost was US$1,148 per patient, as compared to US$25,000-100,000 for treatment with commercial HBIG.

Conclusion

The results of this study suggest that the use of HIP may be a useful and economical approach for the prevention of HBV recurrence post-LT if used in combination with NA. Additional prospective controlled studies in larger populations are needed to confirm these results.  相似文献   
93.
The RecA homolog, E. coli (S. cerevisiae) (RAD51) may modulate hepatitis B virus (HBV) infection by maintaining genome integrity and mediating homologous DNA repairs. In this study, 16 sequence variations were detected by resequencing all exons, the exon-intron boundary, and promoter regions of the human RAD51 gene in DNA samples of 24 unrelated individuals. To investigate the association of common variations in the RAD51 locus with HBV infection and hepatocellular carcinoma (HCC) occurrence, six common polymorphisms were genotyped in a total of 1,103 Korean HBV cohort, composed of 433 spontaneously recovered patients as controls and 670 chronic carriers of HBV, who were stratified further into 327 cirrhosis/chronic hepatitis patients and 343 patients with HCC infected with HBV. Logistic analyses revealed no significant association of RAD51 polymorphisms and haplotypes with HBV clearance and HCC occurrence (P > 0.05). Furthermore, with age of infection as an important factor in disease progression to HCC, results from the Cox proportional hazards analysis showed no significant associations between any of the tested RAD51 variants and the age of onset of HCC (P > 0.05), suggesting that genetic polymorphisms of RAD51 may not play an important role in clearance of HBV and disease progression to HCC. Although studies in other populations are needed to confirm these findings, this preliminary data may contribute to the current knowledge on the pathogenesis of hepatitis.  相似文献   
94.
95.
IntroductionIn disseminated intravascular coagulation (DIC), widespread activation of intravascular coagulation accompanied with florid endothelial activation results in release of unusually large von Willebrand factor (ULvWF) from endothelium. Circulating a disintegrin-like and metalloprotease with thrombospondin type 1 repeats (ADAMTS)-13 may be consumed through the ongoing cleavage of ULvWF, resulting in a secondary deficiency of ADAMTS-13 in DIC. We determined whether ADAMTS-13 activity showed a significant correlation with the activation status of the coagulation system and hospital mortality in DIC.Materials and methodsADAMTS-13 activity was assayed by fluorescence resonance energy transfer assay in 97 patients who were clinically suspected to have DIC.ResultsADAMTS-13 activity gradually decreased based on the DIC score and D-dimer levels and was correlated with the antithrombin level, representing the consumption of ADAMTS-13 during the ongoing coagulation process. There were no correlation between ADAMTS-13 activity and neutrophil CD64 expression as a neutrophil activation marker and circulating IL-6 level as an inflammatory marker. Patients with a low activity of ADAMTS-13 (≤ 56.4%) had a poor survival rate compared to patients with a high activity of ADAMTS-13.ConclusionsWe conclude that ADAMTS-13 activity is strongly correlated with the severity of coagulopathy and hospital mortality. ADAMTS-13 may serve as a diagnostic and prognostic marker of DIC.  相似文献   
96.
97.
The purposes of this study were to investigate the effects of fatigue location and age on changes in postural control induced by localized muscle fatigue, as well as the patterns of recovery post-fatigue. Groups of 16 younger (18–25 years) and 16 older (55–65 years) participants performed submaximal isotonic fatiguing exercises involving the unilateral ankle plantar flexors, knee extensors, and shoulder flexors, and bilateral lumbar extensors. Postural control was assessed during quiet upright stance, from center-of-pressure and center-of-mass time series obtained before and after the fatiguing exercises. Acute effects of fatigue differed between joints, with the most substantial effects evident at the lower back, followed by the ankle. Neither knee nor shoulder fatigue resulted in significant effects on postural control. Significant acute effects of fatigue were found only among the younger group. Recovery of postural control post-fatigue was influenced by age, being more rapid in the younger group, but not by fatigue location. Along with existing evidence, these results may facilitate the development of strategies to prevent occupational falls.  相似文献   
98.
Seol HJ  Yoo HY  Jin J  Joo KM  Kim HS  Yoon SJ  Choi SH  Kim Y  Pyo HR  Lim DH  Kim W  Um HD  Kim JH  Lee JI  Nam DH 《Oncology research》2011,19(8-9):381-390
The most important therapeutic tool in brain metastasis is radiation therapy. However, resistance to radiation is a possible cause of recurrence or treatment failure. Recently, DNA damage checkpoint signaling pathway activation after irradiation has received increasing attention. The association between the expression levels and survival outcome was evaluated to find possible therapeutic targets in brain metastasis. Radiosensitivity of human non-small cell lung cancer cell lines was determined by checking their viability after treatment with varying doses of ionizing radiation (IR). The expression of DNA checkpoint proteins was analyzed by Western blots and immunohistochemistry. On the basis of the clinical data for the patients, the association between the expression of the components and patients' survival was investigated. The expression levels of TopBP1 and phosphorylated Chk1 (P-Chk1) protein were higher in radioresistant lung cancer cell lines compared to radiosensitive cell lines. We previously assessed radiation survival of lung cancer cell lines after treating them with Chk1 inhibitor, AZD7762. AZD7762 significantly sensitized both radioresistant and radiosensitive cells to IR. We also observed a strong inverse relationship between progression-free survival (PFS) and expression level of P-Chk1 and TopBP1. This study, which is the first clinical report that connects DNA damage checkpoints and prognosis of brain metastasis, supports these two proteins to be promising targets for overcoming the radioresistance in brain metastasis.  相似文献   
99.

Background  

The molecular mechanisms of CC (cholangiocarcinoma) oncogenesis and progression are poorly understood. This study aimed to determine the genome-wide expression of genes related to CC oncogenesis and sarcomatous transdifferentiation.  相似文献   
100.
Glial fibrillary acidic protein (GFAP) is an intermediate filament expressed in glial cells that stabilizes and maintains the cytoskeleton of normal astrocytes. In glial tumors, GFAP expression is frequently lost with increasing grade of malignancy, suggesting that GFAP is important for maintaining glial cell morphology or regulating astrocytoma cell growth. Most permanent human glioma cell lines are GFAP negative by immunocytochemistry. Given that the GFAP gene is not mutated in human glioma specimens or glioma cell lines, we considered epigenetic mechanisms, such as promoter methylation, as a cause of silencing of GFAP in these tumors. In this study, we treated known GFAP-negative glioma cell lines with 5-aza-2'-deoxycytidine to examine GFAP promoter hypermethylation. Additionally, we performed bisulfite sequencing on primary glioma samples and glioma cell lines and showed an inverse relationship between GFAP promoter methylation status and GFAP expression. Using a gene reporter assay with the GFAP promoter cloned upstream of a luciferase gene, we showed that methylation of the GFAP promoter downregulates the expression of the luciferase gene. Our results suggest that epigenetic silencing of the GFAP gene through DNA methylation of its promoter region may be one mechanism by which GFAP is downregulated in human gliomas and glioma cell lines.  相似文献   
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