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1.
To verify whether anti-Trypanosoma-cruzi-proteinase antibodies are able to play a role in the development of Chagas' disease, CBA/J and C57BL/6 mice were immunized with purified proteinase fractions: antibody production was studied and passive immunization experiments were carried out. No significant differences were observed in the titre, isotype composition and specificity of the antibodies produced by the mouse strains. Immune sera produced in one strain was able to protect mice of both strains, provided that the challenge did not exceed the number of parasites corresponding to 30-fold the LD50. The data presented suggest that anti-proteinase antibodies may play a role in immunoprotection.  相似文献   
2.
To determine the utility of tissue section immunochemistry in the evaluation of bone marrow involved by lymphoid and plasma cell malignancies, snap-frozen, undecalcified bone marrow core and aspirate samples from 23 patients with these disorders were studied with a battery of monoclonal antibodies. With techniques that preserve architecture, difficult diagnostic cases characterized by core but not aspirate involvement, or the reverse, were resolved. By means of an extensive battery of monoclonal antibodies applied to serial sections, complex tumor cell phenotypes were established in all 23 cases. In addition to the identification of straightforward monoclonal surface immunoglobulin expression in small cleaved cell lymphomas (four cases), the battery approach added immunologic certainty in malignancies with unusual or difficult phenotypes: peripheral T-cell lymphomas with idiosyncratic antigen expression, and chronic lymphocytic leukemias and small cell lymphomas with faint surface immunoglobulin expression (four cases). For the chronic lymphocytic leukemias and the small cell lymphomas, the combined IgD+, B2+, B1+, Ia+, Leu-1+ phenotype taken as a whole had greater utility than any isolated marker. The acute lymphocytic leukemias and the myelomas studied demonstrate the wide range of B-cell antigens that must be detected to account for the variety of B-cell neoplasms encountered. Additionally, the previously undescribed phenotypic subset of CALLA+ myelomas, which is of prognostic relevance, was identified. Marrow frozen section immunotyping is a major asset in the evaluation of patients with lymphoma, leukemia, and myeloma when special care is accorded to tissue handling and to treatment of endogenous peroxidase/pseudoperoxidase and interstitial immunoglobulin.  相似文献   
3.
T-cell homing within germinal centres (GCs) is required for humoral B-cell responses. However, the mechanisms implicated in the recruitment of T cells into the GC are not completely understood. Here we show, by immunohistology, and Northern and Western blots, that in vivo human GC B lymphocytes can express CxC and CC chemokines. Moreover, B-cell subset-specific experiments reveal that interleukin (IL)-8 and regulated on activation, normal, T-cell expressed, and secreted (RANTES) are predominantly expressed by GC centroblast and centrocytes, suggesting that chemokine expression is essential at stages in which B-lymphocytes engage in active antigen-dependent interactions with T lymphocytes. In keeping with this hypothesis, we show that the T cells recruited into the GC correlatively express the receptors for IL-8 and RANTES. We propose that chemokine expression is a key B-cell function that facilitates T-lymphocyte recruitment into the GCs and supports cognate B-cell : T-cell encounters. Moreover, our data are consistent with the impaired homing of T cells to secondary lymphoid organs in mice that are either deficient in CC and CxC chemokines or their receptors.  相似文献   
4.
H. Rangel 《Immunology》1965,8(1):88-94
Cross-reactions between bovine serum albumin and equine serum albumin were studied using heterologous soluble complexes and specifically purified cross-reacting antibody.

Experiments with soluble complexes showed that homologous antigen can displace heterologous antigen specifically bound to antibody but heterologous antigen cannot displace homologous antigen. On gel precipitation tests a specific precipitation resulted when heterologous soluble complex reacted with homologous antigen.

By using equine serum albumin conjugated to polyaminopolystyrene the cross-reacting antibodies from anti-bovine serum albumin imune sera could be isolated. These are divalent 7S, γ-globulin antibodies. A figure of cross-reaction was obtained when these purified antibodies were tested by double diffusion in agar with bovine and equine serum albumins.

The results obtained both with soluble complexes and with purified antibody support the view that cross-reacting antibody is more avid for the homologous than for the heterologous antigen.

  相似文献   
5.
Arginase activity was measured in serum and biopsy from healthy individuals and colorectal cancer patients. Arginase activity in tumor samples (87±7.7 U/g tissue) was significantly higher than in controls (40.7±3.3 U/g tissue). However, serum arginase activity did not show any significant change in both groups. Finally, the micromethod used to quantify arginase activity in this study is superior to other methods because it has increased sensitivity, requires less sample, and is less time-consuming. Arginase differences are significant, according to the t-test (P<0.05). Received: 14 September 2001 / Accepted: 6 February 2002  相似文献   
6.
Identification of two major B cell forms of nodular mixed lymphoma   总被引:2,自引:0,他引:2  
To resolve the controversy over the immunologic nature of nodular mixed lymphoma (NM), we examined nine cases of NM for surface antigens using both tissue section and cell suspension methods. These were contrasted with 12 cases of nodular poorly differentiated lymphocytic lymphoma. We found two major B cell types of NM, those with monoclonal immunoglobulin (SIg+)-positive nodules with an SIg+B1+B2+Ia+T- phenotype (four cases) and those with nodules devoid of immunoglobulin with an SIg-B1+B2-Ia+T- phenotype (five cases). Our SIg+ NM cases appear similar to nodular poorly differentiated lymphocytic lymphoma (SIg+B1+B2+Ia+T-), except suspension assay indicates fewer SIg+ cells in NM. In our SIg- NM cases, the neoplastic nodules consistently expressed B1 and Ia-like antigens and lacked T cells, indicating a B cell neoplasm similar to many large cell lymphomas. By demonstrating a B cell antigen in SIg- nodules, we substantially resolve the controversial NM cases previously called "null" or T cell. The two distinct immunotypes indicate the complexity of B cell antigenic expression in NM and might also explain the variable response to therapy in NM described in previous studies. Finally, we describe NM cases with the simultaneous occurrence of several stages of B cell differentiation. This suggests that some NM cases are not frozen in a single stage of B cell development but may express a range of B cell antigens. NM, then, may be a paradigm of variable, simultaneous B cell maturation.  相似文献   
7.
Neurosurgical Review - The current literature regarding surgical treatment for tumors in the sphenopetroclival (SPC) region is merely scarce. Through a comprehensive literature review, we...  相似文献   
8.
玻璃体切除术治疗外伤性眼内炎62例   总被引:3,自引:1,他引:2  
王金兰  蒋宏苏  惠延年 《医学争鸣》2000,21(2):S018-S018
0 引言 外伤性眼内炎是眼外伤的常见并发症 ,对视力及眼球威协极大 .由于病原体随致伤物直接进入眼内 ,在眼内和玻璃体繁殖 ,产生剧烈炎症反应 ,对眼内组织造成严重破坏 .如不及时而有效的控制 ,终使视力丧失 ,眼球萎缩 .近年随着现代玻璃体手术的发展 ,外伤性眼内炎的治愈率明显提高 .现将我科收治的 6 2例报告如下 .1 对象和方法1 .1 对象 1 996 - 0 6 / 1 998- 0 6我院连续收治 6 2例外伤性眼内炎 ,其中男 5 0例 ,女 1 2例 ,年龄 2~ 45岁 ,平均 1 6 .5岁 .1 4岁以下儿童 38例 ,占 6 1 .3% .以致伤原因分类 :角膜穿通伤30例 ,巩膜穿…  相似文献   
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