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101.
目的:基质金属蛋白酶在急性心肌梗死后的心室重构中起着重要作用,但其调节机制目前尚未明确。实验拟通过动物模型的建立及体外细胞培养,观察急性心肌梗死后单个核细胞表面CD147与心肌成纤维细胞基质金属蛋白酶-9 mRNA表达的关系。 方法:实验于2006—08/2007-06在河北省人民医院临床实验中心完成。实验材料:SD大鼠及SD仔鼠(出生1~3d)购自河北医科大学试验动物中心。实验过程中对动物处置符合动物伦理学标准。实验方法:①将30只大鼠随机分为急性心肌梗死组(n=15)和假手术组(n=15),假手术组只过线不结扎。流式细胞分析法检测大鼠术后24h外周血单个核细胞表面CD147表达。②选择SD仔鼠制备心肌成纤维细胞。将单个核细胞与心肌成纤维细胞以细胞数0.5:1,1:1,2:1混合培养24h后,半定量反转录一聚合酶联反应法检测基质金属蛋白酶-9 mRNA表达。当单核细胞与心肌成纤维细胞2:1混合时,加入CD147单克隆抗体1,2,4μL/L,培养24h后检测基质金属蛋白酶-9 mRNA表达。 结果:①急性心肌梗死后外周血单个核细胞表面CD147表达明显增加。②单个核细胞与心肌成纤维细胞混合培养,随着单个核细胞比例的增加,心肌成纤维细胞基质金属蛋白酶-9 mRNA表达增加。③在单个核细胞与心肌成纤维细胞2:1混合培养体系中,随着加入CD147单克隆抗体浓度的增加,基质金属蛋白酶-9 mRNA生成减少。 结论:急性心肌梗死后单个核细胞表面CD147表达明显增加,对心肌成纤维细胞基质金属蛋白酶-9生成起上游调节作用。  相似文献   
102.
Blastomyces dermatitidis is a dimorphic fungus endemic to northwestern Ontario, Manitoba and some parts of the United States. The fungus is also endemic to parts of Africa. Pulmonary and extrapulmonary findings of a 24-year-old African man who presented with weight loss, dry cough and chronic pneumonia not resolving with antibiotic treatment are presented. The unusual occurrence of pulmonary blastomycosis associated with skin lesions and a moderate pleural effusion is reported.  相似文献   
103.
The diagnosis of mixed-type autoimmune haemolytic anaemia (AIHA) is based on demonstrating the presence of "warm" IgG auto-antibody and "low titre" ( < 64 at 4 degrees C), "high thermal amplitude" (reacting at or >30 degrees C) "cold" IgM auto-antibody. Mixed-type AIHA is uncommon. Red cell agglutination on the peripheral blood film is a common finding in mixed-type AIHA and can lead, initially, to a mis-diagnosis of cold haemmagglutinin disease (CHAD). Mixed-type AIHA is rare and can be idiopathic or secondary, often associated with systemic lupus erythematosus (SLE) and lymphoma. In general, patients with mixed-type AIHA show a dramatic response to steroid therapy and frequently require few or no transfusions. We report two unusual cases of mixed-type AIHA. Case one was unusual as the patient developed AIHA while on steroid medication. Case two, we believe, is the first reported case of splenic T cell angioimmunoblastic non-Hodgkins lymphoma (NHL) associated with mixed-type AIHA. The patient failed to respond to steroids, intravenous immunoglobulin, chemotherapy and treatment with rituximab. The patient received 33 units of red cells over a 9-week period. She finally underwent splenectomy with resolution of haemolysis. DAT tested with monospecific reagents, and thorough serological investigations is required to reach the diagnosis of mixed-type AIHA. Awareness of this condition is important as management may be different from either treating warm AIHA or CHAD.  相似文献   
104.
Obesity is reaching epidemic proportions in the United States. Obesity adversely affects the circulatory system with resultant endothelial dysfunction, which promotes systemic hypertension, coronary artery disease, and vascular calcification. It is believed that the release of adipokines is responsible for this effect. In addition, obesity causes intrinsic changes in the heart including an increase in left ventricular (LV) mass, LV hypertrophy, LV dilatation, left atrial dilatation, and diastolic, as well as systolic dysfunction in some cases. The combination of increased adipose cells and an increase lean muscle mass in obese patients results in high cardiac output and an accompanying increased circulating volume leading to these adaptive changes. Weight loss by means of caloric restriction or surgery results in favorable hemodynamic changes referred to as "reverse remodeling." Regression of LV mass and chamber size has been shown universally. However, some studies have failed to reveal improvement in diastolic function possibly because of confounders such as nutritional deficiency that may occur after weight loss surgery. Some evidence seems to suggest that the greatest regression of LV mass and LV hypertrophy may occur when weight loss is combined with beta-adrenergic blocker therapy (in those who have an indication for the drug) when compared with other antihypertensive drugs versus weight loss alone.  相似文献   
105.
106.
The purpose of this study was to analyze the expression of B cell growth factor (BCGF) receptors and to elucidate the biologic effects of biochemically purified natural BCGF at the B cell precursor stage of human B lineage lymphoid differentiation. The specific binding of radioiodinated high-mol-wt BCGF (125I-HMW-BCGF) and low-molecular-wt BCGF (125I-LMW-BCGF) to fresh marrow blasts from B cell precursor acute lymphoblastic leukemia (ALL) patients was initially investigated. The estimated number of radioiodinated BCGF molecules bound per blast ranged from undetectable to 24.3 X 10(3) for HMW-BCGF, and from 11.5 X 10(3) to 457.8 X 10(3) for LMW-BCGF. In 3H-TdR incorporation assays, 75% of cases showed a significant response to LMW-BCGF with a median stimulation index of 9.3. By comparison, only 33% of cases showed a significant response to HMW-BCGF with a median stimulation index of 2.4. Subsequently, B cell precursor colony assays were performed to assess and compare the biologic effects of BCGF on leukemic B lineage lymphoid progenitor cells. Among 28 cases studied, 57% responded to both HMW-BCGF and LMW-BCGF, 21% responded only to LMW-BCGF, and the remaining cases showed no proliferative response to either growth factor. The response patterns of virtually pure populations of FACS- sorted leukemic B cell precursors were essentially identical to the proliferative responses of unsorted leukemic B-cell precursors. Synergistic effects between HMW-BCGF and LMW-BCGF were observed in 80% of the cases that responded to both. The numbers of cell-bound radioiodinated BCGF molecules, the stimulation indices, as well as the number of B cell precursor colonies in BCGF-stimulated cultures showed a marked interpatient variation. Patients with structural chromosomal abnormalities (SCAs) involving 12p11-13 or patients with a Philadelphia chromosome showed a greater HMW-BCGF response at the level of leukemic progenitor cells than did other patients (P = .02). The LMW-BCGF response was significantly greater for patients with SCA than for patients without SCA (P = .04). The response of leukemic progenitor cells to HMW-BCGF or LMW-BCGF did not correlate with sex, age, disease status, FAB morphology, WBC at diagnosis, or immunophenotype. To our knowledge, this study represents the first detailed analyses of BCGF receptor expression and BCGF effects in B cell precursor ALL. The data presented provide direct evidence for the expression of functional receptors for both HMW-BCGF and LMW-BCGF in B cell precursor ALL.  相似文献   
107.
Cytogenetic and histologic correlations in malignant lymphoma   总被引:9,自引:0,他引:9  
Although a number of studies have indicated correlations between histologic subtypes of tumors and certain nonrandom chromosome changes, cytogenetic studies of lymphoma are in an early stage compared to those of leukemia. No comprehensive analysis of available data has so far been attempted in the literature either. Here we present an analysis of chromosome changes and their correlation with subtypes of lymphoma studied by conventional histology and cell surface markers, as observed in two sets of data: a group of 65 karyotypically abnormal tumors sequentially ascertained and studied by us during the period January 1, 1984 to April 30, 1985, and a larger data set derived by combining our data with those from two published series from the University of Minnesota that are comparable to our data. These combined data, which comprise the largest data set on the cytogenetics of lymphomas assembled so far, enabled a comprehensive analysis of correlation between chromosome change and tumor histology and the patterns of chromosome instability in these tumors. We found several significant associations, some previously described and others now recognized, between nonrandom chromosome gains, breaks, translocations, and deletions and histologic subtypes of tumors that characterize lymphomas. The data indicate that finding of chromosome breaks at certain sites (eg, 8q24, 14q32, 18q21) is of diagnostic value in dealing with cases of unusual lymphoma. Furthermore, nonrandom chromosome breakage exhibited three distinct patterns that reflected three levels of etiologically relevant genetic change.  相似文献   
108.
The goal of this phase II multicenter clinical trial was to evaluate a new intensive chemotherapy program for adults with untreated acute lymphoblastic leukemia (ALL) and to examine prospectively the impact of clinical and biologic characteristics on the outcome. One hundred ninety-seven eligible and evaluable patients (16 to 80 years of age; median, 32 years of age) received cyclophosphamide, daunorubicin, vincristine, prednisone, and L-asparaginase; 167 patients (85%) achieved a complete remission (CR), 13 (7%) had refractory disease, and 17 (9%) died during induction. A higher CR rate was observed in younger patients (94% for those < 30 years old, 85% for those 30 to 59 years old, and 39% for those > or = 60 years old, P < .001) and in those who had a mediastinal mass (100%) or blasts with a T-cell immunophenotype. Eighty percent of B-lineage and 97% of T-cell ALL patients achieved a CR (P = .01). The coexpression of myeloid antigens did not affect the response rate or duration. Seventy percent of those with cytogenetic or molecular evidence of the Philadelphia (Ph) chromosome and 84% of those without such evidence achieved a CR (P = .11). Patients in remission received multiagent consolidation treatment, central nervous system prophylaxis, late intensification, and maintenance chemotherapy for a total of 24 months. After a median follow-up time of 43 months, the median survival for all 197 patients is 36 months; the median remission duration for the 167 CR patients is 29 months. Favorable pretreatment characteristics relative to remission duration or survival are younger age, the presence of a mediastinal mass or lymphadenopathy, a white blood cell count (WBC) less than 30,000/microL, L1 morphology, T or TMy immunophenotype, and the absence of the Ph chromosome. The estimates of the proportion surviving at 3 years are 69% for patients less than 30 years old, 39% for those 30 to 59 years old, 89% for those who had a mediastinal mass, 59% with WBC less than 30,000/microL, 63% with L1 morphology, 69% for T or TMy antigen expression, and 62% for those who lack the Ph chromosome. Fifteen patients (8%) had no unfavorable prognostic factors and have an estimated probability of survival at 5 years of 100% (95% confidence interval, 77% to 100%). This intensive chemotherapy regimen produces a high remission rate and a high proportion of durable remissions in adults with ALL.  相似文献   
109.
The objectives were to determine quantitative liver function prospectively in patients with rheumatoid arthritis (RA) treated with low-dose methotrexate (MTX), to search for risk factors for a loss of quantitative liver function and to assess the relationship between quantitative liver function and histological staging. A total of 117 patients with RA (ACR criteria, 85 women, mean age 59 yr) had measurements of galactose elimination capacity (GEC), aminopyrine breath test (ABT) and liver enzymes [aspartate amino transferase (AST), alanine amino transferase (ALT), alkaline phosphatase (AP), 7-glutamyl transferase (GGT), bile acids, bilirubin, albumin] before treatment with weekly i.m. MTX injections and every year thereafter. In 16 patients, liver biopsies were performed. Before the introduction of MTX, mean GEC was 6.6 mg/min/kg [5th to 95th percentile (5-95 PC) 5.1- 8.5; reference range 6.0-9.1] and mean ABT was 0.80% kg/mmol (5-95 PC 0.42-1.30: reference range 0.6-1.0). During treatment with MTX [mean weekly dose 11.8 mg (5-95 PC 5.4-20.2), mean observation period 3.8 yr (5-95 PC 0.4-6.9)], significant declines of GEC (-0.12 mg/min/kg per year. t = 3.30, P < 0.002) and ABT (-0.06% kg/mmol per year, t = 4.81, P < 0.001) were observed. Negative correlations were found between the annual change in GEC and GEC at baseline (Rs = -0.40, P < 0.0001), and the annual change in ABT and ABT at baseline (Rs = -0.43, P < 0.0001). No correlations were found between the annual change in GEC or ABT and weekly MTX dose, age or percentage of increased liver enzymes, and no effect of a history of alcohol consumption > 30 g/week became evident. Two patients with Roenigk grade III had impaired quantitative liver function, while 14 patients with Roenigk grades I and II exhibited a high variability of GEC and ABT from normal to abnormal values. The continuous declines in GEC and ABT observed deserve attention in patients with prolonged treatment. Patients with a low GEC or ABT at baseline seem not to be at increased risk for a further loss of quantitative liver function. An impaired GEC or ABT does not necessarily concur with hepatic fibrosis on histological examination.   相似文献   
110.
The activation of factor XI initiates the intrinsic coagulation pathway. Until recently it was believed that the main activator of factor XI is factor XIIa in conjunction with the cofactor high molecular weight kininogen on a negatively charged surface. Two recent reports have presented evidence that in a purified system factor XI is activatable by thrombin together with the soluble polyanion dextran sulfate. To assess the physiological relevance of these findings we studied the activation of factor XI in normal and factor XII-deficient plasma. We used either kaolin/cephalin or dextran sulfate as a surface for the intrinsic coagulation pathway, tissue factor to generate thrombin via the extrinsic pathway, or the addition of alpha-thrombin directly. 125I-factor XI, added to factor XI-deficient plasma at physiologic concentrations (35 nmol/L), is rapidly cleaved on incubation with kaolin. The kinetics appear to be exponential with half the maximum cleavage at 5 minutes. Similar kinetics of factor XI cleavage are seen when 40 nmol/L factor XIIa (equal to 10% of factor XII activation) is added to factor XII-deficient plasma if an activating surface is provided. Tissue factor (1:500) added to plasma did not induce cleavage of factor XI during a 90-minute incubation, although fibrin formation within 30 seconds indicated that thrombin was generated via the extrinsic pathway. Adding 1 mumol/L alpha-thrombin (equivalent to 50% prothrombin activation) directly to factor XII deficient or normal plasma (with or without kaolin/cephalin/Ca2+ or dextran sulfate) led to instantaneous fibrinogen cleavage, but again no cleavage of factor XI was observable. We conclude that in plasma surroundings factor XI is not activated by thrombin, and that proposals of thrombin initiation of the intrinsic coagulation cascade are not supportable.  相似文献   
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