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41.
The F105 mAb, identified in an HIV-1-infected individual, binds to a discontinuous epitope on the HIV-1 gp120 envelope glycoprotein, blocks the binding of gp120 to the CD4 viral receptor, and neutralizes a broad range of HIV-1 isolates. This study reports the primary nucleotide and deduced amino acid sequences of the rearranged heavy and light chains of the mAb F105. This IgG1k mAb uses a VH gene member of the VH4 gene family (V71-4) and is productively rearranged with a D-D fusion product of the dlr4 and da4 germline DH genes and the JH5 gene. This rearranged heavy chain gene expresses the VH4-HV2a idiotope, which is seen in human monoclonal IgM cold agglutinins. The F105 Vk appears to be derived from the Humvk325 germline gene and is rearranged with a Jk2 gene. For both chains, the mutational pattern in the rearranged VH and VL genes is indicative of an antigen-driven process. These studies show that production of a broadly neutralizing anti-HIV-1 antibody that recognizes determinants within the CD4 recognition site of the envelope glycoprotein is achieved by rearrangement of the V71-4 and Humvk325 germline variable region genes along with selected individual point mutations in the rearranged genes.  相似文献   
42.
Background contextWound dehiscence and surgical site infections (SSIs) can have a profound impact on patients as they often require hospital readmission, additional surgical interventions, lengthy intravenous antibiotic administration, and delayed rehabilitation. Negative pressure wound therapy (NPWT) exposes the wound site to negative pressure, resulting in the improvement of blood supply, removal of excess fluid, and stimulation of cellular proliferation of granulation tissue.PurposeTo assess the incidence of wound infection and dehiscence in patients undergoing long-segment thoracolumbar fusion before and after the routine use of NPWT.Study designRetrospective study.Patient sampleOne hundred sixty patients undergoing long-segment thoracolumbar spine fusions were included in this study.Outcome measuresPostoperative incidence of wound infection and dehiscence.MethodsAll adult patients undergoing thoracolumbar fusion for spinal deformity over a 6-year period at Duke University Medical Center by the senior author (CB) were included in this study. In 2012, a categorical change was made by the senior author (CB) that included the postoperative routine use of incisional NPWT devices after primary wound closure in all long-segment spine fusions. Before 2012, NPWT was not used. After primary wound closure, a negative pressure device is contoured to the size of the incision and placed over the incision site for 3 postoperative days. We retrospectively review the first 46 cases in which NPWT was used and compared them with the immediately preceding 114 cases to assess the incidence of wound infection and dehiscence.ResultsOne hundred sixty (NPWT: 46 cases, non-NPWT: 114 cases) long-segment thoracolumbar spine fusions were performed for deformity correction. Baseline characteristics were similar between both cohorts. Compared with the non-NPWT cohort, a 50% decrease in the incidence of wound dehiscence was observed in the NPWT patient cohort (6.38% vs. 12.28%, p=.02). Similarly, compared with the non-NPWT cohort, the incidence of postoperative SSIs was significantly decreased in the NPWT cohort (10.63% vs. 14.91%, p=.04).ConclusionsRoutine use of incisional NPWT was associated with a significant reduction in the incidence of postoperative wound infection and dehiscence.  相似文献   
43.
BackgroundIncidental durotomies occur in up to 17% of spinal operations. Controversy exists regarding the short- and long-term consequences of durotomies.PurposeThe primary aim of this study was to assess the effect of incidental durotomies on the immediate postoperative complications and patient-reported outcome measures.Study designProspective study.Patient sampleA total of 1,741 patients undergoing index lumbar spine fusion were selected from a multi-institutional prospective data registry.Outcome measuresPatient-reported outcome measures used in this study included back pain (BP-Visual Analog Scale), leg pain (LP-Visual Analog Scale), and Oswestry Disability Index.MethodsA total of 1,741 patients were selected from a multi-institutional prospective data registry, who underwent primary lumbar fusion for low back pain and/or radiculopathy between January 2003 and December 2010. We collected and analyzed data on patient demographics, postoperative complications, back pain, leg pain, and functional disability over 2 years, with risk-adjusted propensity score modeling.ResultsIncidental durotomies occurred in 70 patients (4%). Compared with the control group (n=1,671), there was no significant difference in postoperative infection (p=.32), need for reoperation (p=.85), or symptomatic neurologic damage (p=.66). At 1- and 2-year follow-up, there was no difference in patient-reported outcomes of back pain (BP-Visual Analog Scale), leg pain (LP-Visual Analog Scale), or functional disability (Oswestry Disability Index) (p>.3), with results remaining consistent in the propensity-matched cohort analysis (p>.4).ConclusionWithin the context of an on-going debate on the consequences of incidental durotomy, we found no difference in neurologic symptoms, infection, reoperation, back pain, leg pain, or functional disability over a 2-year follow-up period.  相似文献   
44.
Relatively nonmyelotoxic drugs and drug combinations were investigated for their ability to eliminate malignant cells from human bone marrow. In vitro 90% inhibitory concentration (IC90) doses were established on granulocyte macrophage colony-forming units (GM-CFU) in culture of bone marrow by using the GM-CFU assay for the following drugs: 4- hydroperoxycyclophosphamide (4-HC), Adriamycin, L-asparaginase, bleomycin, hydrocortisone, VP-16, spirogermanium, Taxol, and vincristine. The leukemic cell kill efficiency of these drugs at IC90 doses was compared with that of 4-HC on acute lymphoid leukemia (ALL) cell lines by using the limiting-dilution assay. Under these conditions, no single drug was superior to 4-HC. To increase the in vitro effect in leukemic cell kill, combinations of vincristine with hydrocortisone, Adriamycin, VP-16, and 4-HC were investigated. Vincristine at 1 to 5 micrograms/mL increased the marrow cytotoxicity of hydrocortisone, Adriamycin, and VP-16, but it was protective (subadditive) with 4-HC. Vincristine and 4-HC in combination was additive to supraadditive on ALL cell lines, increased the leukemic cell kill by one to two logs above 4-HC alone at IC90 doses (P less than .05), and was not affected by the addition of excess marrow cells. The recommended doses for chemopurging in clinical studies are vincristine, 1 to 5 micrograms/mL, plus 4-HC, 5 micrograms/mL.  相似文献   
45.
StudyonliverinjurymodelsinducedbyCCl4DGalandANITinmiceYANGXinBo1,HUANGZhengMing1,CAOWenBin1,ZHENGMing1,CHENHongYan1,ZHAN...  相似文献   
46.
EfectsofserafromburnpatientsonhumanhepatocyticviscoelasticityWANGXiaoJun,LUOXiangDong,LUOQinandYANGZongChengBurnResearchIn...  相似文献   
47.
48.
目的:观察多聚二磷酸腺苷(ADP)核糖合成酶(PARP)抑制剂对血管紧张素Ⅱ(AngⅡ)刺激的乳鼠心脏心肌重构的预防作用.方法:新生大鼠心肌细胞原代培养,传代,用PARP抑制剂3-AB预处理细胞,观察PARP抑制剂对AngⅡ诱导心肌细胞PARP激活、PARPl表达,细胞内ROS产生和c-fos,ANP,β/aMHC基因表达的影响.结果:AngⅡ显著诱导心肌细胞PARP激活,ROS产生增加,PARPl、c-los、β/a-MHC、ANP基因表达增加.给予3-AB预处理可显著抑制AngⅡ诱导的上述变化.结论:AngⅡ可以诱导培养的心肌细胞内PARP激活,PARPl蛋白表达增加,3-AB预处理可以明显降低AngⅡ诱导的心肌细胞内异常基因表达增加,提示PARPl参与了心室重构的发生发展过程.  相似文献   
49.
前列腺特异抗原研究进展与挑战(摘要)   总被引:1,自引:0,他引:1  
前列腺特异抗原(PSA)发现四分之一世纪以来,已成为诊断前列腺癌最有价值的肿瘤标志物。前列腺癌在男性癌症发病中占首位。自从80年代中期第一代检测PSA的方法问世以来,前列腺癌的发病率有了显著改变。这部分归功于PSA检测的增加,从而使前列腺癌得到早期诊断,这有利于将癌症控制在发病早期,增加治愈的可能性。虽然PSA是一个有效的肿瘤标志物,并具有器官特异性,但其癌症特异性不高。PSA升高也可见于其他良性前列腺疾病,尤其当PSA浓度在4~10μg/L时。这个浓度范围被称为“诊断灰色区域”。对PSA分子结构的研究主要集中…  相似文献   
50.
王瑞  安宁  付力军 《医学争鸣》2000,21(4):508-508
1 病例报告 男 ,71岁 ,因排尿困难于 1999- 0 9- 0 4入院 .B超确诊前列腺增生 5 a,既往无高血压、心脏病及心率失常史 .查体 :Bp17/ 10 k Pa,心界不大 ,心率 6 2次· min- 1 ,心律齐 .下腹部可触及涨大的膀胱 ,约耻骨上 4指 .入院时 ECG正常 .肝肾功能无异常 ,确诊前列腺增生伴急性尿潴留 .首先予导尿 ,导出尿液约 90 0 m L,之后 im乙稀雌酚 1mg,2 h后患者突发心慌、胸闷、气短、心前区疼痛 .发现患者大汗BP12 /6 k Pa,P110次· min- 1 ,R2 8次· min- 1 ,心率绝对不齐 ,脉搏明显短促 ,两肺底可闻及湿性罗音及哮鸣音 ,ECG示房颤 ,心…  相似文献   
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