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991.
重症肌无力患者胸腺内B淋巴细胞亚群CD20的分布及临床意义 总被引:1,自引:0,他引:1
目的了解胸腺内B淋巴细胞与重症肌无力发生的关系。方法用免疫组化方法,分析胸腺瘤伴有和不伴有重症肌无力的患者肿瘤外胸腺内B淋巴细胞亚群CD20的分布。结果发现伴有重症肌无力患者的胸腺内CD20阳性细胞呈显著集合和中等集合,与不伴有重症肌无力者差异有极显著意义(χ2=26.032,P<0.01);CD20阳性细胞分布程度与胸腺瘤的分期呈负相关(γ=0.7),与重症肌无力临床分型无相关(γ<0.4)。结论提示在重症肌无力的发病因素中,胸腺的病理改变比胸腺瘤更重要。由于抗乙酰胆碱受体抗体的异质性,B淋巴细胞集合程度并不能反映临床症状的轻重。 相似文献
992.
L. Liu B. Ren H. Zhang J. Li Q. Fu J. Jiang S. Deng J. Qiu G. Chen J. Fei L. Chen C. Wang 《Transplantation proceedings》2018,50(8):2392-2397
Background
We calculated the population pharmacokinetics of mizoribine in adult Chinese patients and compared the parameters with those of Japanese patients to determine whether there are any ethnic differences in blood concentration transition between these 2 populations.Methods
The blood concentrations of mizoribine in 21 Chinese patients who were administered mizoribine after renal transplantation were measured at 304 time points. The absorption lag time, absorption rate constant, apparent distribution volume, and oral clearance were thereafter calculated and compared with the respective Japanese references.Results
The absorption lag time, absorption rate constant, and apparent distribution volume calculated in this study were, respectively, 0.353 hour, 0.856 hour?1, and 0.776 L/kg. The oral clearance was calculated as 2.18 times the creatinine clearance using creatinine clearance as a function. The absorption rate constant, apparent distribution volume, and oral clearance are determinants of the maximum blood concentration, trough, and area under the blood concentration time curve. The relative absorption rate constant, apparent distribution volume, and oral clearance were 0.9-, 0.9-, and 1.2-fold, respectively, in Chinese patients compared with those in Japanese patients. These values are within the confidence limit, suggesting that there is no significant PK difference between the 2 ethnic groups.Conclusions
Results of this study showed no ethnic difference in blood mizoribine concentration transition between Chinese and Japanese patients. In addition, the population pharmacokinetic parameters obtained in this study are useful in determining the initial dosage or in the Bayesian analysis of mizoribine concentrations using scarce time points. 相似文献993.
Chen G Zhang Z Gu J Qiu J Wang C Kung R Fei J Deng S Li J Huang G Fu Q Chen L 《Transplantation proceedings》2010,42(10):4094-4098
IntroductionPulmonary mycosis, a severe complication following kidney transplantation, is associated with a high rate of mortality. The incidence of and independent risk factors for its development have not been well studied.MethodsWe retrospectively reviewed 2573 kidney transplant recipients. Patients were divided into case and control groups based on a diagnosis of pulmonary mycosis. The recipient baseline characteristics, posttransplant complications, immunosuppressive regimens and antibiotic usages were analyzed to identify independent risk factors.ResultsThe total incidence of pulmonary mycosis among kidney recipients was 2.1%. Upon univariate analysis, patients in the case group differed significantly from the controls based upon: older age, higher retransplantation rate, longer dialysis time, induction with ATG or anti-CD25 monoclonal antibodies, maintenance treatment with FK506 or MMF, broad-spectrum antibiotics, higher incidences of acute rejection episodes, DGF, impaired liver function, leukopenia, cytomegalovirus infection, and delayed incisional healing (P < .05). Multivariate analysis showed that older age, retransplantation, ATG induction, FK506/MMF, broad-spectrum antibiotics, leukopenia, and delayed incisional healing were independent risk factors for pulmonary mycosis.ConclusionsThe use of more potent immunosuppressive regimens seems to increase the rate of pulmonary mycosis. Patients who have five or more independent risk factors are at high risk for developing pulmonary mycosis. 相似文献
994.
Pulmonary hypertensive effect of heparin and protamine interaction: evidence for thromboxane B2 release from the lung 总被引:1,自引:0,他引:1
The characteristic pulmonary hypertensive effect of the heparin and protamine interaction has been studied in the isolated pig lung preparation using sequential autologous blood perfusate and dextran perfusate. A significant (p less than 0.001) increase in pulmonary artery pressure at constant flow was seen in 10 of 14 dextran and 12 of 15 blood perfusions. The average increase for dextran was 112 percent and for blood, 109 percent. Antihistamines did not inhibit the response. However, this was abolished in all 11 animals treated with aspirin. In 11 intact swine, thromboxane B2 blood levels increased significantly (p less than 0.01) from 0.46 +/- 0.38 ng/dl to 2.97 +/- 1.5 ng/dl. Thus, pulmonary hypertension associated with protamine reversal of heparinization is associated with prostaglandin release from the lung, and this does not require mediation of platelets or leukocytes. 相似文献
995.
Regulatory T cells (Tregs) are essential for the establishment and maintenance of immune tolerance, suggesting a potential therapeutic role for Tregs in transplantation. However, Treg administration alone is insufficient in inducing long‐term allograft survival in normal hosts, likely due to the high frequency of alloreactive T cells. We hypothesized that a targeted reduction of alloreactive T effector cells would allow a therapeutic window for Treg efficacy. Here we show that preconditioning recipient mice with donor‐specific transfusion followed by cyclophosphamide treatment deleted 70–80% donor‐reactive T cells, but failed to prolong islet allograft survival. However, infusion of either 5 × 106 Tregs with direct donor reactivity or 25 × 106 polyclonal Tregs led to indefinite survival of BALB/c islets in more than 70% of preconditioned C57BL/6 recipients. Notably, protection of C3H islets in autoimmune nonobese diabetic mice required islet autoantigen‐specific Tregs together with polyclonal Tregs. Treg therapy led to significant reduction of CD8+ T cells and concomitant increase in endogenous Tregs among graft‐infiltrating cells early after transplantation. Together, these results demonstrate that reduction of the donor‐reactive T cells will be an important component of Treg‐based therapies in transplantation. 相似文献
996.
Wang H Ye L Yu L Xie G Cheng B Liu X Jin Y Wu S Zhu T Chen Q Fang X 《Anaesthesia and intensive care》2011,39(1):55-60
This study assessed the performance of Sequential Organ Failure Assessment, Logistic Organ Dysfunction Score and Multiple Organ Dysfunction Score in outcome prediction in severe sepsis. A total of 528 consecutive patients with a diagnosis of severe sepsis were enrolled from two surgical intensive care units of university hospitals in China. Clinical and laboratory data of patients were collected and admission and maximum values of each scoring system were calculated. Areas under the receiver operating characteristic curve, which were used to assess discrimination, were 0.80, 0.83 and 0.74 for admission Sequential Organ Failure Assessment, Logistic Organ Dysfunction Score and Multiple Organ Dysfunction Score respectively, and 0.91, 0.93 and 0.86 for corresponding maximum values respectively. Calibration assessed by the Hosmer-Lemeshow statistic was better with admission (chi2 = 18.2) and maximum Logistic Organ Dysfunction Score (chi2 = 19.6) than with admission (chi2 = 98.1) and maximum Multiple Organ Dysfunction Score (chi2 = 30.9). Brier Scores, indicating the overall performance of the scores, were 0.18, 0.17 and 0.22 for admission Sequential Organ Failure Assessment, Logistic Organ Dysfunction Score and Multiple Organ Dysfunction Score respectively, and 0.12, 0.10 and 0.15 for their maximum counterparts respectively. This study found good performance of both admission Sequential Organ Failure Assessment and Logistic Organ Dysfunction Score in severe sepsis, and a slightly weaker performance of admission Multiple Organ Dysfunction Score. Since poor calibration was observed in Logistic Organ Dysfunction Score and Multiple Organ Dysfunction Score, we suggest further study of customisation of these scores in critical illness with severe sepsis. 相似文献
997.
Vlastos G Fornage BD Mirza NQ Bedi D Lenert JT Winchester DJ Tolley SM Ames FC Ross MI Feig BW Hunt KK Buzdar AU Singletary SE 《American journal of surgery》2000,179(6):446-452
BACKGROUND: The goal of this study was to examine the role of ultrasonography in detecting axillary lymph node metastases in stage II breast cancer patients after induction chemotherapy (IC). METHODS: Of 172 consecutive patients with T1-3, N0-1, M0 breast cancer registered in a prospective IC trial, a subset of 130 evaluable patients were chosen, with (1) both physical and ultrasonographic examinations of the axilla before and after IC; (2) exactly four cycles of IC; (3) no presurgical radiation therapy; and (4) an axillary lymph node dissection. RESULTS: Before IC, 32 patients (25%) were negative for axillary involvement by both physical and ultrasonographic examinations. After IC, this number increased to 64 (49%). Of these, 31 (48%) were positive by pathology examination. In most cases, however, the residual tumor was minimal. CONCLUSIONS: Stage II breast cancer patients who were or became node negative by both ultrasonographic and physical examinations after IC had a 48% incidence of nodal metastases. Because the residual tumor was minimal, irradiation may be sufficient for adequate local control of the axilla. 相似文献
998.
纤溶酶原激活物抑制物1与肝细胞癌 总被引:5,自引:0,他引:5
目的研究纤溶酶原激活物抑制物1(PAI1)在肝细胞癌(HCC)蛋白和mRNA水平的表达及其与HCC生物学特性的关系。方法取HCC石蜡标本48例,肝良性肿瘤石蜡标本12例(对照组)做免疫组化染色;液氮冻存HCC标本20例,肝血管瘤5例(对照组)做免疫印迹杂交。结果肝癌细胞与癌周细胞及对照组肝细胞相比,PAI1抗原蛋白和mRNA表达显著升高,差异有显著意义,P值分别<001和<0.05。术后2年内死亡病例与生存病例相比,PAI1阳性率有显著意义的升高,P<005。PAI1和纤溶酶原激活物(uPA)及其受体(uPAR)同时阳性患者与同时阴性患者相比,前者侵袭性病例较后者升高有显著性意义(P<005)。结论HCC中PAI1蛋白和mRNA表达明显增高。PAI1与HCC浸润转移和预后密切相关。 相似文献
999.
Xu X Ye Q Xu N He X Luo G Zhang X Zhu J Zhang Y Nilsson-Ehle P 《Transplantation proceedings》2006,38(9):2769-2773
The present study investigated the expression pattern of apolipoprotein M (apoM) mRNA in a rat model of hepatic ischemia-reperfusion injury (IRI). Animals were ischemic for 1 hour followed by various reperfusion times. As expected, serum alanine aminotransferase levels were significantly increased under IRI, which indicated the severity of liver injury. Hepatic mRNA levels of HSP70, which is the most common characterized protein within the family of heat-shock proteins (HSP), were significantly increased after 0.5 to 3 hours of IRI. Plasma C-reactive protein, high-density lipoprotein-cholesterol, and lipoprotein (a) levels were significantly increased after 1-hour ischemia followed by 0.5 to 3 hours of reperfusion. Interestingly, similar to HSP70, apoM mRNA levels in the liver were gradually increased after 0.5 to 3 hours of IRI, whereas it returned to a lower level after 6 or 24 hours of IRI, which indicated that hepatic apoM expression was significantly influenced by the acute phase of IRI. However, plasma apoM levels were not increased in parallel, even slightly decreasing after 0.5 or 1 hour of IRI. We concluded that apoM mRNA expression pattern, like HSP70, in the liver showed rapid, significant changes during hepatic local IRI. 相似文献