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11.
为了探讨创伤后机体细胞免疫、体液免疫及红细胞免疫功能障碍与外周血单个核细胞HLA-DR表达率之间的关系,本文选择了30例重度复合伤病人。在住院治疗期间,连续观察了患者受伤当日、伤后第3、10、20d及出院前一天外周血单个核细胞HLADR表达率的变化及其与细胞免疫、体液免疫及红细胞免疫功能状况之间的相关性,发现创伤病人自受伤当日至出院前外周血单个核细胞膜上HLA-DR表达率的变化无统计学意义(P>0.05),提示创伤后免疫功能障碍不是由于外周血单个核细胞HLA-DR表达异常所致。  相似文献   
12.
Cell mediated immunity (CMI) was assessed by the ImmuKnow assay in 12 patients after kidney transplantation, who presented with viral infection. Treatment included lowering of immunosuppression in all cases and antiviral treatment if indicated. The assay was repeated during the follow up. The ImmuKnow assay at time of presentation of viral infections was 56.8 ± 58.2 (range 3–178; median 22) ATP ng/ml. With the clearance of viral infection and lowering of immunosuppression, the assay showed an increase in the level of CMI at 194.5 ± 118.9 (range 53–409; median 150) ATP ng/ml. There was viral clearance or stabilization in all cases and there was no incidence of allograft rejection. The ImmuKnow assay of CMI can be used to titrate initial immunosuppression reduction and its subsequent increase, in patients with viral infection after transplantation.  相似文献   
13.
Histoplasmosis is a rarely reported deep mycotic infection in the Indian context. Oral or oropharyngeal manifestation can occur as an isolated symptom or as part of a disseminated process associated with immunosuppression especially with HIV and diabetes. Five cases of head and neck histoplasmosis accrued over 6 years in a tertiary referral cancer institute were reviewed. All these patients presented clinically as cancer. In three patients, the marked pseudoepitheliomatous hyperplasia led to a mistaken biopsy diagnosis of malignancy following which definitive surgical treatment was performed. The subsequent excision revealed typical features of histoplasmosis. Isolated oral presentation of histoplasmosis can mimic malignancy both clinically as well as pathologically, leading to potentially disastrous consequences. A high index of suspicion in those with overt or hidden immunosuppression and a deep wedge biopsy to demonstrate the organisms in the subepithelial tissue is recommended. This work has been presented in the “Slide seminar on Infections and Infestations” in the IAP-ID pre conference CME in APCON 2006.  相似文献   
14.
We report a first case of a 19 year old female suffering from an acute lymphatic leukemia, which developed shortly after the initiation of a chemotherapy an intracerebral hemorrhage and fatal multiple brain abscesses caused by Bacillus cereus. There is much evidence that Bacillus cereus in immunocompromised patients leads to a localized, necrotizing tissue infection due to the production of potent toxins and usually results in rapid and fulminant tissue destruction. Bacillus species has an special affinity for the CNS mediated by phospholipase C, which tends to associate with the lipid membranes of the brain.  相似文献   
15.
. This is a report of unexplained anemia that persisted for 4 months in an adolescent renal transplant patient receiving immunosuppression that included prednisone, tacrolimus, and mycophenolate mofetil. This patient required monthly blood transfusions for fatigue, palpitations, and hematocrit levels between 15% and 17%. In addition, his posttransplant course was notable for the development of insulin-dependent diabetes mellitus. While receiving low-dose prednisone, he was switched from tacrolimus to cyclosporin and tapered off insulin injections over the next 2 months. At 4.5 months post-transplantation, further diagnostic evaluation was suggestive of parvovirus B19 infection as the cause for our patient’s chronic anemia. After testing negative for serum-specific parvovirus B19 IgM and IgG antibodies, parvovirus B19 infection was detected in blood by the polymerase chain reaction. Treatment with intravenous immunoglobulin (1 g/kg per day × 2 days) resulted in normalization of both his reticulocyte count and hematocrit within 6 weeks. At 4 months after receiving the immunoglobulin infusion, he has maintained a normal hematocrit level and stable renal function without requiring further blood transfusions. Received August 23, 1996; received in revised form and accepted November 20, 1996  相似文献   
16.
Acute rejection, occurring with a reported frequency of 50–70%, is still a dominating problem after liver transplantation. Medication with ursodeoxycholic acid (UDCA) has beneficial effects in different cholestatic conditions and has also been shown to reduce HLA class I antigen expression on hepatocytes in patients with PBC. Since August 1989 we have consecutively treated all patients with primary graft function with UDCA (n = 41). Patients transplanted in the first half of 1989 served as a control group (n = 8). All patients in this study were given sequential quadruple drug immunosuppression. The treatment group were given oral UDCA 10 mg/kg per day. During the first postoperative month, 17% of the UDCA-treated patients had an episode of acute rejection compared with 75% of the control patients (P < 0.01). Liver biochemistry tests 1 month postoperatively were significantly better in patients treated with UDCA. The results suggest that adjuvant treatment with UDCA reduces acute liver graft rejection.  相似文献   
17.
 We employed intracerebral co-transplantation of foetal xenogeneic striatal mouse tissue and allogeneic rat substantia nigra into the adult rat brain to elucidate the effects of xenogeneic mouse graft on the function and survival of an allogeneic rat graft in 6-hydroxydopamine lesioned Sprague-Dawley rats. Foetal mouse striatum (STR) and rat substantia nigra (VM) were transplanted as non-pooled separate deposits or a pooled cell suspension with or without cyclosporin A (Cy A). Immunosuppressed recipients of pooled rat and mouse co-grafts showed a significantly better compensation of amphetamine-induced rotational behaviour compared with non-immunosuppressed animals with pooled rat and mouse co-grafts 3 and 6 weeks post-grafting.Tyrosine hydroxylase (TH) immunohistochemistry revealed a non-significant reduction in survival in pooled (1806.3±367.5 cells) rat and mouse co-transplants without immunosuppression compared with immunosuppressed pooled (3383.3±732.7 cells) animals with allo- and xenogeneic tissue and controls (3506.4±839.3 cells). Graft volumes were significantly reduced in pooled transplants without immunosuppression (0.1±0.026 mm3; ANOVA post-hoc SchefféF-test, P<0.0001) compared with immunosuppressed recipients (0.7±0.1 mm3) and controls (0.6±0.1 mm3). In non-pooled allo- and xenogeneic grafts without immunosuppression the survival rate of the TH-immunoreactive cells and graft volumes were reduced (2359.3±479.5 cells; 0.2±0.043 mm3) compared with immunosuppressed animals (2927.3±946.6 cells; 0.6±0.2 mm3) and controls (2701.1±693.8 cells; 0.3±0.1 mm3) without reaching a level of significance. Rejection of mouse tissue was observed in all non-immunosuppressed recipients. In summary: (i) continued immunosuppression yielded significant beneficial effects on function and beneficial effects on survival of pooled grafts with an immunogenetic disparity; (ii) the rejection of a xenogeneic graft component may compromise survival and function of other, allogeneic graft components; and (iii) transplantation of non-pooled allo- and xenogeneic tissues may result in a better survival of the graft compared with pooled cell suspensions. Received: 25 March 1996 / Accepted: 1 December 1996  相似文献   
18.
Extracts of Tripterygium wilfordii Hook F.(TWHF ) are effective in traditional Chinesemedicine for treatment of autoimmune diseasessuch as rheumatoid arthritis, systemic lupus ery thematosus, nephritis and asthma [1, 2]. Trip tolide, a diterpenoid triepoxide, is derived fromTWHF and is responsible for most of the immuno suppressive and anti inflammatory effects ofTWHF. Triptolide has been shown to be effectivein the treatment of autoimmune diseases, …  相似文献   
19.
CD46, the major component of the measles virus (MV) receptor complex and a member of the regulators of complement activity (RCA) gene cluster, is down-regulated in MV-infected cells. We investigated whether the reduction of surface CD46 correlates with enhanced sensitivity of lymphoid and monocytic cells to lysis by activated complement. On human U937 cells, acutely or persistently infected with MV-Edmonston (ED) vaccine strain, infection-dependent down-regulation of CD46 confers sensitivity to activated complement, regardless of the pathway of activation and the specificity of the activating antibodies. Interestingly, down-regulation of CD46 alone is sufficient to confer susceptibility of cells to complement lysis despite the continued surface expression of other RCA proteins such as CD35 and CD55. In primary cultures, both peripheral blood lymphocytes and macrophages are efficiently lysed in the presence of complement activated via the alternative pathway after MV infection. In contrast to the MV-ED infection, infection of cells with the lymphotropic MV wild-type strain WTF does not down-regulate CD46. Cells infected with MV-WTF do not exhibit enhanced susceptibility to complement lysis. These data suggest that MV strains similar to WTF that do not down-regulate CD46 may have an enhanced potential for replication and dissemination within the human host, whereas complement-mediated elimination of cells infected with CD46-down-regulating strains of MV, such as ED, may limit the spread of MV infection, and could thus represent an attenuating factor for MV.  相似文献   
20.
蛋白酶体抑制剂对T淋巴细胞增殖活化的影响   总被引:1,自引:1,他引:1       下载免费PDF全文
目的:探讨蛋白酶体(proteasome)抑制剂LAC(lactacystin)和β-LAC(β-lactacystin)对外周血T淋巴细胞增殖、活化的影响。方法: 以植物血凝素(phytohemagglutinin,PHA)作为刺激剂,经流式细胞仪检测T淋巴细胞增殖(BrdU掺入率),检测CD3+CD25+/CD3+及CD3+CD69+/CD3+细胞比例, 同时用RT-PCR检测蛋白酶体11S调节蛋白PA28及细胞因子IL-2 mRNA的表达。结果: (1)对预先活化的T淋巴细胞,LAC和β-LAC降低 T淋巴细胞BrdU掺入率(P<0.05);(2)LAC和β-LAC不影响T淋巴细胞CD69的表达(各时点,P>0.05),而显著抑制T细胞表面抗原CD25表达(48 h、72 h,P<0.05);(3)与对照组相比,LAC和β-LAC明显下调T淋巴细胞PA28、IL-2 mRNA的表达(48 h、72 h,P<0.05)。结论: LAC和β-LAC能够显著抑制T淋巴细胞增殖,这一效应与其抑制T淋巴细胞表面早期活化抗原CD25表达,下调PA28、IL-2 mRNA的表达有关。  相似文献   
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