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851.
852.
Ely  P; Wallace  PK; Givan  AL; Graziano  RF; Guyre  PM; Fanger  MW 《Blood》1996,87(9):3813-3821
To show that macrophages can be effectively targeted against malignant B cells, bispecific antibodies (BsAb) were constructed from two antibodies having specificity for the high-affinity Fc receptor for IgG (Fc gamma RI/CD64) and the B-cell differentiation antigens CD19 and CD37. Using a flow cytometry-based assay and confocal imaging, we show that these constructs mediated significant phagocytosis of B lymphocytes by macrophages that could be enhanced with interferon gamma (IFN gamma) and IFN gamma in combination with macrophage colony- stimulating factor. BsAb-dependent phagocytosis was triggered through Fc gamma RI and could be blocked only by using F(ab')2 fragments from the parent molecule or by cross-linking Fc gamma RI. BsAb-dependent phagocytosis was not blocked by antibodies to the other Fc receptors, Fc gamma RII and Fc gamma RIII. Because these antibody constructs bind to an epitope outside the Fc gamma RI ligand binding site, we show that autologous serum, polyclonal IgG, and monomeric IgG1 did not block BsAb- dependent phagocytosis, whereas autologous serum and the IgG fractions blocked parent molecule monoclonal antibody-dependent phagocytosis due to the avid binding of monomeric IgG to Fc gamma RI. Finally, BsAb- mediated phagocytosis was effective against the malignant B cells of patients with mantle cell lymphoma, prolymphocytic leukemia, and chronic lymphocytic leukemia. Based on these studies, we propose that BsAbs may provide an effective means of immunomodulation for patients with B-cell malignancies.  相似文献   
853.
Hereditary dysfibrinogenemia in a patient with thrombotic disease   总被引:2,自引:1,他引:2  
Carrell  N; Gabriel  DA; Blatt  PM; Carr  ME; McDonagh  J 《Blood》1983,62(2):439-447
A new case of congenital dysfibrinogenemia, in which the patient has severe thrombotic disease, is reported. The abnormal fibrinogen molecules are characterized by normal fibrinopeptide release with thrombin and defective polymerization in the formation of fibrin. Clotting times with ancrod and reptilase are significantly prolonged. All other coagulation tests (except those for fibrinogen function) are normal, and the patient has no other underlying disease. The apparent paradox of defective fibrinogen, which clots abnormally and is yet associated with thrombotic disease, can be explained by further analysis of the patient's fibrinogen. The two important functional properties of this fibrinogen are: (1) it forms fibrin gels that are extremely rigid, and (2) the fibrin is highly resistant to lysis by plasmin. Thus, although the abnormal fibrinogen forms defective clots, the fibrin that is formed cannot be removed by the fibrinolytic system. These results provide a molecular explanation for the thrombotic disease in this patient. This abnormal fibrinogen appears to have unique characteristics and has been designated as fibrinogen Chapel Hill Ill.  相似文献   
854.
Chronic granulomatous disease (CGD) is characterized by the failure of phagocytic leukocytes to kill certain bacteria and fungi. This is caused by deficiencies in one of the components of NADPH oxidase, the enzyme in phagocytic leukocytes that generates superoxide. In a rare, autosomal recessive form of CGD, a 67-kD cytosolic component of NADPH oxidase (p67-phox) is missing. Until now, mutations in the gene coding for this protein have not been identified. We now report on a 10-year- old girl with lymph node and liver abscesses who was recognized as an A67(0) CGD patient by lack of NADPH oxidase activity in her granulocytes, a cytosolic defect in a cell-free oxidase system, and lack of immunoreactive material with an antiserum against the p67-phox protein. mRNA for this protein was present in normal amounts in her monocytes. This p67-phox mRNA was reverse-transcribed, and the coding region was amplified by polymerase chain reaction in six overlapping fragments and was sequenced. The patient appeared to be homozygous for a G-233-->A mutation, resulting in a nonconservative amino acid change (78Gly-->Glu). This mutation was also found in the genomic DNA of this patient but not in that of 38 normal donors. Both parents and a sister proved to be carriers of the disease, as deduced from the mutation in only one allele. The carrier state was also manifested by intermediate superoxide production by their intact granulocytes and in the cell-free system.  相似文献   
855.
856.
晚期头颈部鳞癌患者需要化疗、放疗和(或)手术相结合的综合治疗,但对化疗的时机选择长期存在争论。Meta分析显示:当前被认为是标准治疗方法的化放疗已被广泛用于晚期头颈部鳞癌患者,并能够将患者2年及5年生存率提高8%。诱导化疗具有许多优点,如评估治疗效果、筛选可保存器官的患者。顺铂和氟尿嘧啶的联合应用已有20年的历史,但最近已被顺铂、氟尿嘧啶和紫杉醇所替代,后者现被认为是诱导化疗的标准治疗模式。  相似文献   
857.
OBJECTIVE: To determine the frequency of detection of human herpesvirus-8 (HHV-8) in HIV-related oral ulcers. DESIGN: Analysis of archived biopsy material. METHODS: Nested polymerase chain reaction of DNA extracts. RESULTS: HHV-8 DNA was detected in six of 10 oral ulcers of HIV-positive patients without oral Kaposi's sarcoma (KS) lesions and five of 11 oral KS lesions. The positive non-KS samples were derived from various oral sites. CONCLUSIONS: In HIV-positive people, HHV-8 can infect oral tissues that are not affected by KS.  相似文献   
858.
PM Bartold 《Oral diseases》1995,1(4):238-253
The connective tissues of the periodontium are composed of two soft tissues and two hard tissues—each of which has unique features. This review considers the constituents of normal, healthy periodontal connective tissues together with an appraisal of the changes in the connective tissue matrices of the periodontium which occur during the development of periodontitis. Recent developments in this field have paved the way for new and exciting vistas in periodontal diagnosis and regeneration which, ultimately, are two important goals in periodontal therapy.  相似文献   
859.
本刊经Philip M.Meyers博士代表写作组授权,将“ Reporting standards for angioplasty and stent-assisted angioplasty for intracranial atherosclerosis”译为中文在本刊刊登。标准中对患者的选择、颅内动脉狭窄程度的判断、最佳内科治疗、围手术期处理、血管内治疗、术后并发症等,进行了规范化总结,拟为今后的临床试验和研究的规范化确定标准,以保证结果的可比性,对神经介入医师具有重要的指导意义。  相似文献   
860.
背景和目的颅内动脉粥样硬化可造成众多患者发生缺血性卒中。过去10年间血管内治疗技术已经取得突破性进展,能够开展颅内动脉粥样硬化性狭窄的血管内治疗。采用血管成形术和支架辅助阻管成形术治疗颅内动脉粥样硬化性狭窄的患者例数不断增加。但是鉴于目前血管成形术和支架辅助血管成形术治疗狭窄性和闭塞性颅内动脉粥样硬化仍缺乏普遍认可的临床和放射学评估以及皿管内治疗技术及预后的规范,此文就是提供该方面报告标准、术语和书面定义的共识性建议。报告摘要报告标准是在技术评价委员会、神经介入外科学会、介入放射学会、美国神经外科医师协会和神经外科医师代表大会的脑血管外科分会、美国神经科学会的卒中和介入神经病学分会的联合写作组共同起草完成。对1997年1月-2007年12月间,美国国立图书馆医学文献数据库(PubMed)进行计算机检索,旨在确定已发表的狭窄性颅内动脉粥样硬化的神经介入治疗中,能用作质量评价基准的资料。我们尽可能地确定影响神经介入治疗成功及并发症可能性的危险调节变量。对狭窄性和闭塞性颅内动脉粥样硬化进行麻管内治疗的临床试验设计中,不同临床和技术问题可能影响血管内治疗的疗效,此文章为这些问题提供相关的理论基础。该指南中包括对血管内治疗试验报告标准的建议。虽然制定规范和标准主要是出于研究用途,但是这也将有助于临床实践,还适用于所有相关的出版物。结论总之,报告标准提出的建议将有助于构建有效的研究数据库,同时促进产生科学可靠的研究结果,使相似研究之间或内部能够进行可靠的比较。存某些情况下,为报告和出版的一致性,本文中的定义可能是写作组专家的共识性建议。这些建议将促使不同研究组的结果具有直接可比性。  相似文献   
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