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631.
Two monoclonal antibodies (To15 and 4KB128) specific for the B cell- associated CD22 antigen (135,000 mol wt) are described. On immunoenzymatic analysis of cryostat tissue sections, these antibodies strongly label both mantle zone and germinal center B lymphoid cells in secondary lymphoid follicles (and also scattered extrafollicular lymphoid cells) but are unreactive with other cell types (with the exception of weak reactivity with some epithelioid histiocytes). These reactions differ from those of monoclonal antibodies B1 and B2 (anti- CD20 and CD21) but are similar to those of the pan-B antibody B4 (anti- CD19). One of the anti-CD22 antibodies (To15) has been tested extensively by immunoenzymatic labeling on greater than 350 neoplastic lymphoid and hematological samples. The CD22 antigen was found in tissue sections in most B cell-derived neoplasms, the major exceptions being myeloma (all cases negative) and a small proportion of high-grade lymphoma (6% of cases negative). In cell smears, the antigen could be found on neoplastic cells in most B cell lymphoproliferative disorders, including common acute lymphoblastic leukemia (ALL) (90% positive) and B cell chronic lymphocytic leukemia (CLL) (89% positive). We conclude that anti-CD22 antibodies are of value for identification of human B cell lymphoproliferative disorders (especially when used in conjunction with anti-CD19 antibodies). Previous reports that the CD22 antigen is absent from many B cell neoplasms are probably due to its being expressed within the cytoplasm of immature B cells rather than on their surface.  相似文献   
632.
To examine directly the hypothesis that T cell growth factor (TCGF) interacts with target cells in a fashion similar to polypeptide hormones, the binding of radiolabeled TCGF to various cell populations was investigated. The results indicate that TCGF interacts with activated T cells via a receptor through which it initiates the T cell proliferative response. Internally radiolabeled TCGF, prepared from a human T leukemia cell line and purified by gel filtration and isoelectric focusing, retained biological activity and was uniform with respect to size and charge. Binding of radiolabeled TCGF to TCGF-dependent cytolytic T cells occurred rapidly (within 15 rain at 37 degrees C) and was both saturable and largely reversible. In addition, at 37 degrees C, a receptor- and lysosome-dependent degradation of TCGF occurred. Radiolabeled TCGF binding was specific for activated, TCGF-responsive T cells. Whereas unstimulated lymphocytes of human or murine origin and lipopolysaccharide-activated B cell blasts expressed few if any detectable binding sites, lectin- or alloantigen-activated cells had easily detectable binding sites. Moreover, compared with lectin- or alloantigen-activated T cells, long-term TCGF-dependent cytolytic and helper T cell lines and TCGF-dependent neo-plastic T cell lines bound TCGF with a similar affinity (dissociation constant of 5-25 pM) and expressed a similar number of receptor sites per cell (5,000-15,000). In contrast, a number of TCGF-independent cell lines of T cell, B cell, or myeloid origin did not bind detectable quantities of radiolabeled TCGF. Binding of radiolabeled TCGF to TCGF-responsive cells was specific, in that among several growth factors and polypeptide hormones tested, only TCGF competed for binding. Finally, the relative magnitude of T cell proliferation induced by a given concentration of TCGF closely paralleled the fraction of occupied receptor sites. As the extent of T cell clonal expansion depends on TCGF and on the TCGF receptor, the dissection of the molecular events surrounding the interaction of TCGF and its receptor that these studies permit, should provide new insight into the hormonelike regulation of the immune response by this lymphokine.  相似文献   
633.
BACKGROUND: Perioperative blood transfusion (BT) appeared to have adverse effects on survival after surgery for malignant tumors while pretransplantation BT suppressed allograft rejection. Interest grew in the effect of BT on postoperative recurrence of Crohn's disease. STUDY DESIGN AND METHODS: To determine the effect of perioperative BT on the recurrence of Crohn's disease after primary surgery, the medical histories of 148 patients with Crohn's disease, 62 males and 86 females (49 nonparous and 37 parous), were reviewed. Eighty-seven patients received perioperative BT. RESULTS: Overall, perioperative BT showed no effect on recurrence. Patients with Crohn's disease limited to the ileum had a better prognosis with regard to recurrence than did patients with Crohn's disease located in the colon or located in both ileum and colon, but the difference was not significant. Perioperative transfusion seemed to protect against recurrent disease after colon resection, which might be explained by the fact that colon resections, which often necessitate perioperative BT, generally result in a shorter bowel segment at risk for recurrent disease. Overall, parous women showed a worse prognosis than nonparous females and men (p = 0.022). Transfusions had a beneficial effect in parous women (p = 0.068) and, after correction for type of operation, this beneficial effect was significant (p = 0.026). After perioperative BT, parous women had a similar prognosis with respect to recurrent Crohn's disease as nonparous females and men. CONCLUSION: Perioperative BT has a beneficial effect on the postoperative recurrence of Crohn's disease in parous women.  相似文献   
634.
对291例颈动脉内膜剥脱术后患者进行随访研究,1例术后即期死亡;22例(6.3%)在术后发生脑中风,17例为中度中风,5例为严重中风,即期中风的病因包括:14例手术部位颈动脉血栓形成(14/22,64%),4例术中或术后即期脑栓塞,2例阻断颈动脉所致脑缺血,1例脑出血,1例原因不明。此外讨论了术后中风的危险因素和处理方法。  相似文献   
635.
In vivo or in vitro immunity to murine leukemia virus (MuLV)-induced leukemia cells which do not effectively produce virus, has been difficult to demonstrate. Because immunizations with allogeneic murine leukemia cells have been used to confer syngeneic tumor immunity to virus- producing cells, we attempted to generate lymphocytes, cytotoxic to syngeneic nonproducer leukemia cells, by stimulating normal murine spleen cells with allogeneic nonproducer leukemia cells in mixed tumor lymphocyte culture (MTLC) reactions in vitro. Secondary allogeneic MTLC of normal C57BL/6 or DBA/2 spleen cells effectively produced syngeneic tumor-specific cytotoxic lymphocytes. Target cells lysed in lymphocyte- mediated cytolysis (LMC) assays, included both Friend and Rauscher virus- induced syngeneic murine leukemia cells and chemically-induced hematopoietic tumor cells. Syngeneic tumor cells were lysed regardless of whether they produced infectious MuLV or expressed viral antigens gp-71, p-30, or p-12 at the cell surface. Syngeneic normal cells (thymus, lymph node, or Concanavalin A-stimulated spleen cells) used as targets in LMC assays were uneffected by lymphocytes harvested from secondary allogeneic MTLC. Several other in vitro culture treatments including secondary syngeneic MTLC and repetitive mixed lymphocyte culture stimulations were incapable of generating tumor-specific cytotoxic lymphocytes. Based upon these results, we propose that secondary MTLC stimulation of normal spleen cells with allogeneic nonproducer leukemia cells selects for the proliferation of two subpopulations of antigen-specific cytotoxic lymphocytes. The population capable of effecting syngeneic tumor cell lysis is directed against tumor-associated cell surface antigens which may be distinct from viral structural proteins or glycoproteins. The growth of these tumor-specific cytotoxic lymphocytes may be enhanced by a soluble allogeneic effect factor produced by the proliferation of the second subpopulation of lymphocytes generated in repetitive allogeneic MTLC, namely those lymphocytes with specificities directed against differing histocompatibility antigens.  相似文献   
636.
干燥综合征(SS)是一种慢性自身免疫性疾病,常侵犯泪腺、唾液腺等外分泌腺,同时还会造成肺、肾、消化和神经系统损害甚至累及全身器官。其病因复杂,发病机制目前尚未完全阐明。本病临床治疗为对症治疗,常用药物为免疫抑制剂,糖皮质激素等。白芍总苷辅助治疗本病可改善患者的外分泌腺功能,具有较好的临床疗效和安全性。本文从白芍总苷治疗SS的相关机制进行综述,以期为相关实验研究及临床提供更多的理论依据。  相似文献   
637.
目的 应用网络药理学分析金藤清痹颗粒治疗急性痛风性关节炎(acute gouty arthritis,AGA)的作用机制,并建立AGA大鼠模型进行验证。方法 在清热解毒、活血止痛治法指导下,通过TCMSP数据库搜集金藤清痹颗粒的活性成分及靶点,利用GeneCards、NCBI数据库等搜集AGA相关靶点,与金藤清痹颗粒作用靶点整合后,构建共有靶点蛋白质-蛋白质相互作用(protein-protein interaction,PPI)网络和“金藤清痹颗粒-中药-活性成分-靶点-AGA”网络,并进行基因本体(gene ontology,GO)功能及京都基因与基因组百科全书(Kyoto encyclopedia of genes and genomes,KEGG)通路富集分析。雄性SD大鼠随机分为空白组、模型组、秋水仙碱(0.3 mg/kg)组和金藤清痹颗粒低、中、高剂量(1.05、2.10、4.20 g/kg)组,每组6只,踝关节注射单钠尿酸盐(monosodium urate,MSU)晶体建立AGA大鼠模型。采用游标卡尺测量大鼠踝关节直径,计算踝关节肿胀度;采用全自动生化仪检测血清尿酸(serum uric acid,SUA)、C反应蛋白(C-reactive protein,CRP)水平;采用苏木素-伊红(HE)染色观察踝关节组织病理变化;采用qRT-PCR、ELISA和Western blotting检测踝关节组织及血清中关键靶点和信号通路的表达。结果 共检索到金藤清痹颗粒110种活性成分、212个作用靶点,272个AGA治疗靶点,共有靶点29个,关键靶点有白细胞介素-1β(interleukin-1β,IL-1β)、肿瘤坏死因子(tumor necrosis factor,TNF)及IL-6,涉及TNF信号通路、IL-17信号通路和NOD样受体信号通路等。大鼠踝关节注射MSU晶体后明显肿胀(P<0.01),SUA及CRP显著升高(P<0.05、0.01),滑膜组织增生明显、结构紊乱,有大量炎症细胞浸润,NOD样受体热蛋白结构域相关蛋白3(NOD-like receptor thermal protein domain associated protein 3,NLRP3)、NIMA相关蛋白激酶7(NIMA-related kinases 7,NEK7)、凋亡相关斑点样蛋白(apoptosis-associated speck-like protein containing a CARD,ASC)、半胱氨酸天冬氨酸蛋白酶-1(cystein-asparate protease-1,Caspase-1)、消皮素D(gasdermin D,GSDMD)、IL-18、IL-1β、IL-6及TNF-α表达水平明显升高(P<0.01);秋水仙碱或金藤清痹颗粒治疗后,有效缓解踝关节肿胀(P<0.05、0.01),SUA及CRP均显著降低(P<0.05、0.01),关节滑膜增生、炎症细胞浸润均得到改善,同时显著抑制IL-1β、TNF-α及IL-6等靶点和NOD样受体信号通路的表达(P<0.05、0.01)。结论 金藤清痹颗粒对AGA大鼠具有明显的保护作用,其机制可能与抑制NOD样受体信号通路的异常激活,降低炎症因子水平,改善关节滑膜增生、炎症细胞浸润有关。  相似文献   
638.
Jaundice should be considered as a first clinical sign preceding severe invasive bacterial infection or sepsis in patients of all ages including childhood and adolescence. Early laboratory investigations and MR imaging studies for osteomyelitis or myositis are paramount to avoid progression to life‐threatening sepsis and significant morbidity and mortality.  相似文献   
639.
痛风是由于机体嘌呤代谢异常和(或)尿酸排泄障碍所致的一组异质性疾病。生物碱是一类含有氮的有机化合物,广泛存在于植物中,用于痛风等多种疾病引起的炎症反应。通过查阅国内外最新相关文献报道,对生物碱抗痛风作用及作用机制的研究进展进行综述,以期为生物碱的进一步研究和临床应用提供科学依据和理论指导。  相似文献   
640.
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