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71.
72.
八项肝纤维化血清标志物比较研究   总被引:36,自引:0,他引:36  
目的比较血清血小板衍生生长因子-BB(PDGF-BB)、转化生长因子-β1(TGF-B1)、基质金属蛋白酶抑制剂-1(TIMP-1)、基质金属蛋白酶-1(MMP-1)、透明质酸(HA)、Ⅲ型前胶原(PC Ⅲ)、Ⅳ型胶原(C Ⅳ)和层黏连蛋白(LN)及外周血单个核细胞(PBMC)内TIMP-1 mRNA、MMP-1 mRNA在肝纤维化中的诊断价值。方法常规肝穿活检、组织病理学诊断;RT-PCR检测PBMCs中MMP-1 mRNA、TIMP-1 mRNA水平;酶标法检测血清PDGF-BB、TGF-β1、TIMP-1和MMP-1含量;放射免疫法检测血清HA、PC Ⅲ、C-Ⅳ和LN含量。结果经ROC曲线分析,血清PDGF-BB、TIMP-1、HA、PC Ⅲ、C-Ⅳ、LN和TIMP-1 mRNA的AUC分别为0.985、0.726、0.318、0.728、0.727、0.583、0.463、0.876;血清PDGF-BB和PBMCs中TIMP-1 mRNA的灵敏度和特异度分别为90%、95%,73.7%、100%;两者联合检测的灵敏度为97.4%,特异度为95.0%。结论八项指标中,血清PDGF-BB的诊断价值最大。在筛选肝纤维化患者时,以血清PDGF-BB、PBMC中TIMP-1 mRNA联合检测最佳。  相似文献   
73.
Streeter  RR; Presant  CA; Reinhard  E 《Blood》1977,50(3):427-432
In order to determine the prognostic significance of thrombocytosis in idiopathic sideroblastic anemia, the clinical courses of 17 patients were reviewed. Six patients (36%) had thrombocytosis, and none developed acute leukemia. Nine patients (53%) had normal platelet counts, and one developed acute leukemia. Two patients (12%) were thrombocytopenic, and one died of acute leukemia. There was little correlation between survival and platelet count. Sixty-three additional case reports of idiopathic sideroblastic anemia were collected from the literature. Analysis of those patients and the patients in the present study documented transformation to acute leukemia in 5 of 9 (56%) thrombocytopenic patients, 4 of 54 (7.4%) patients with normal platelet counts, and 0 of 17 patients with thrombocytosis (p less than 0.05). Therefore patients with idiopathic sideroblastic anemia and thrombocytosis appear to have a decreased likelihood of leukemic transformation.  相似文献   
74.
Scandella  D; Mattingly  M; de Graaf  S; Fulcher  CA 《Blood》1989,74(5):1618-1626
Human factor VIII(FVIII) inhibitors are pathologic, circulating antibodies that inactivate FVIII. We have examined the location of epitopes on the FVIII protein for inhibitors from hemophilia A and nonhemophilic individuals. The inhibitors were of type I or type II in the kinetics of their inactivation of FVIII. A cDNA clone of human FVIII was used to express defined FVIII protein fragments in Escherichia coli for immunoblotting with inhibitor plasma. An epitope for 18 heavy-chain inhibitors was localized to the aminoterminal 18.3 Kd of the A2 domain. Two of these inhibitors also recognized an epitope located between A1 and A2 domains. Similarly, an epitope for 23 light- chain inhibitors was localized to the C2 domain. Weaker epitopes for 13 of the same inhibitors within the C1 and C2 domains were also observed. Four of the 23 inhibitors in addition bound strongly to the A3 domain. Most inhibitors (22 of 23) were neutralized in vitro only by the FVIII fragments to which they bound on immunoblots; however, one inhibitor that was neutralized by a fragment containing the A1 domain did not bind to it on immunoblots. Conversely, 3 of 3 inhibitors that bound to the A3 domain and 5 of 15 that bound to the A2 domain were not neutralized by the corresponding fragments. The epitope specificity of an inhibitor did not depend on its source or type. Our results show that FVIII inhibitors bind to limited areas within the heavy and light chains of FVIII. Some inhibitor plasmas contain additional antibodies that may not be inhibitory.  相似文献   
75.
Morrison  AE; Ludlam  CA; Kessler  C 《Blood》1993,81(6):1513-1520
Data have been collected from 47 centers in Europe and North America on the treatment with porcine factor VIII concentrate of 74 acute bleeding episodes in 65 patients with acquired hemophilia. The median initial anti-human factor VIII auto-antibody inhibitor level was 38 Bethesda unit (BU)/mL (range 1.2 to 1,024) whereas that against porcine was 1 BU/mL (range 0 to 15). The mean initial dose of porcine factor VIII infused was 84 IU/kg, which increased the plasma factor VIII:C activity by 0.85 IU/mL. Therapy was continued for a mean of 8.5 days during which time the average number of infusions was 11. Objective clinical responses were rated as good or excellent in 78% of recipients. Side effects were uncommon; only one patient experienced a severe anaphylactic reaction necessitating the discontinuation of porcine FVIII therapy. After therapy, no increase in the median level of anti- human FVIII or anti-porcine antibody was noted in the group as a whole, although 13 patients showed individual increases in either anti-human or anti-porcine antibody levels or both of more than 10 BU/mL. Of the 7 patients who subsequently rebled, 5 were successfully re-treated and 2 did not respond to further porcine factor VIII treatment. Porcine factor VIII is safe and clinically effective treatment for bleeding episodes associated with acquired hemophilia and should be considered as first-line therapy for patients whose acquired anti-factor VIII:C antibody cross-reacts with porcine factor VIII:C at low levels.  相似文献   
76.
Cai  SP; Chang  CA; Zhang  JZ; Saiki  RK; Erlich  HA; Kan  YW 《Blood》1989,73(2):372-374
We used in vitro DNA amplification by the polymerase chain reaction and nonradioactive probes for prenatal diagnosis of beta thalassemia in Chinese from the Guangdong province. Exact molecular diagnoses were made in all 20 fetuses studied over a 6-month period. We conclude that this method of prenatal diagnosis for beta thalassemia is a viable approach in many parts of the world where this disease is common.  相似文献   
77.
Foon  KA; Nakano  GM; Koller  CA; Longo  DL; Steis  RG 《Blood》1986,68(1):297-300
Two patients with hairy cell leukemia with massive splenomegaly and severe pancytopenia were treated with recombinant alpha-A interferon (IFN-alpha-2a). There was no significant response to a trial of IFN- alpha-2a (11 and 20 weeks) with respect to blood counts or spleen size. Subsequent treatment with 2'-deoxycoformycin (dCF) for 8 consecutive weeks (4 mg/m2/wk) resulted in normalization of spleen size and a normalization of peripheral blood counts and bone marrow in one patient. The second patient demonstrated a reduction in spleen size and improved blood counts following 9 weeks of dCF therapy but eventually became refractory. This demonstrates that dCF is non-cross-resistant with interferon and confirms the efficacy of dCF in nonsplenectomized patients.  相似文献   
78.
High-dose intravenous gammaglobulin (polyvalent immunoglobulin G) has been shown to be of benefit in some patients with immune thrombocytopenic purpura (ITP), possibly by producing reticuloendothelial system blockade. We studied this approach in patients refractory to random donor platelet transfusion using an IV IgG preparation manufactured by the Swiss Red Cross. Eleven adult patients with acute leukemia received either 0.4 g IgG/kg/d intravenously X five days (four patients) or 0.6 g/kg/d X five days (seven patients). All patients had high levels of lymphocytotoxic antibody and poor responses to random donor platelets. Except for mild headaches in two patients, there were no side effects related to the IgG infusions. All patients had significant elevations of serum IgG on the day after completion of treatment. Either random donor or partially HLA-matched platelet transfusions were administered the day after and, in some cases, during the IgG therapy. No patient had an improvement in one hour posttransfusion platelet count increments. Two additional patients received pooled platelet concentrates incubated for 30 minutes at 37 degrees C with IgG at a final concentration of 3 g% prior to transfusions. These results indicate that high-dose IgG, an extremely expensive treatment, cannot be recommended for alloimmunized adults with leukemia.  相似文献   
79.
We have compared multiple assays for the P-glycoprotein (Pgp/MDR1) phenotype in fresh and thawed adult acute leukemia to validate and quantitate measures for the expression and function of Pgp. The results are related to the Pgp-expressing KB8 and KB8-5 call lines. The most sensitive assay was the measurement of modulation of the rhodamine 123 (R123) fluorescence by 2 micromol/L PSC833, followed by the modulation of the probe calcein-AM. We also found a good intralaboratory and interlaboratory correlation between the values of the R123/PSC833 assay for fresh as well as thawed samples. In addition, the affects of PSC833 on 3H-daunorubicin (DNR) accumulation, DNR fluorescence, and 3H- vincristine accumulation were very similar. The correlation between the DNR/PSC833 and R123/PSC833 test was r = .86 (N = 51). The modulation of drug accumulation by 8 micromol/L verapamil was the some as the PSC833 effect for DNR (117%, N = 21), but was higher for vincristine in every single case (161% v 121%, N = 22; P< .001), indicating additional verapamil effects, not related to Pgp. The correlation of the staining of viable cells for Pgp with the monoclonal antibody MRK16 was r = .77 (N = 52) for the R123/PSC833 functional test and r = .84 (N = 50) for the DNR/PSC833 test. From these results it could be calculated that a maximal increase of the mean DNR accumulation of about 50% can be achieved by blocking Pgp pump activity with PSC833 in leukemic blast samples with the highest mean Pgp expression. Subpopulations of blast calls with higher Pgp activity are likely to be present. Their relevance has to be studied further. The methods outlined here allow the reliable, quantitative monitoring of the Pgp/MDR1 phenotype in leukemias in multicentered, clinical Pgp modulation studies.  相似文献   
80.

Introduction

Sympathetic nervous system hyperactivity is common after subarachnoid hemorrhage (SAH). We sought to determine whether uncontrolled prolonged heart rate elevation is a risk factor for adverse cardiopulmonary events and poor outcome after SAH.

Methods

We prospectively studied 447 SAH patients between March 2006 and April 2012. Prior studies define prolonged elevated heart rate (PEHR) as heart rate >95 beats/min for >12 h. Major adverse cardiopulmonary events were documented according to the predefined criteria. Global outcome at 3 months was assessed with the modified Rankin Scale (mRS).

Results

175 (39 %) patients experienced PEHR. Nonwhite race/ethnicity, admission Hunt–Hess grade ≥4, elevated APACHE-2 physiological subscore, and modified Fisher score were significant admission predictors of PEHR, whereas documented pre-hospital beta-blocker use was protective. After controlling for admission Hunt–Hess grade, Cox regression using time-lagged covariates revealed that PEHR onset in the previous 48 h was associated with an increased hazard for delayed cerebral ischemia, myocardial injury, and pulmonary edema. PEHR was associated with 3-month poor outcome (mRS 4–6) after controlling for known predictors.

Conclusions

PEHR is associated with major adverse cardiopulmonary events and poor outcome after SAH. Further study is warranted to determine if early sympatholytic therapy targeted at sustained heart rate control can improve outcome after SAH.  相似文献   
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