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31.
32.
目的:对蒙药苏格木勒-3水提物进行化学成分研究,构建较为全面的化学成分谱,为苏格木勒-3水提物有效物质基础研究奠定基础。方法:采用超高液相色谱串联四级杆飞行时间质谱(UPLC-Q-TOF-MS)技术,使用ESI离子源,通过mzCloud与mzVoult软件以及质谱裂解规律,并结合对照品及相关文献资料比对进行定性分析。结果:经过分析,从蒙药苏格木勒-3水提物中共鉴定出42个成分,主要包括氨基酸、酚酸类、黄酮类、内酯类、生物碱类及其他类等6类成分,并对各成分的药材来源进行归属。结论:本研究全面、快速、准确地分析了蒙药苏格木勒-3水提物的化学成分,为其药效物质基础和质量控制等研究奠定了基础。 相似文献
33.
Molecular heterogeneity in acute leukemia lineage switch 总被引:1,自引:0,他引:1
Gagnon GA; Childs CC; LeMaistre A; Keating M; Cork A; Trujillo JM; Nellis K; Freireich E; Stass SA 《Blood》1989,74(6):2088-2095
Six cases of acute leukemia that underwent lineage switch from acute lymphocytic leukemia to acute myelogenous leukemia are reported. The mean age of the patients was 24 years, time to conversion was 36 months, and survival after conversion was only 3 months. Of the three cases which showed abnormal metaphases at both diagnosis and conversion, two (cases 2, 5) showed related cytogenetic abnormalities, and the third showed (case 3) independent chromosomal changes. Molecular analysis for immunoglobulin heavy chain and T-cell receptor beta chain genes showed that five of the six cases had rearrangement of at least one of these lymphoid associated genes at conversion to acute myelogenous leukemia. The single case (case 3) in which there were no lymphoid gene rearrangements at conversion was also the only case in which independent karyotypic abnormalities at diagnosis and conversion were demonstrated. Our findings suggest that lineage switch can represent either relapse of the original clone with heterogeneity at the molecular level or the emergence of a second new leukemic clone without molecular heterogeneity. 相似文献
34.
目的探讨宫内炎症暴露对早产儿固有免疫应答的影响。方法 2013年6月至2014年6月出生、胎龄35周的早产儿47例纳入本研究。依据胎盘病理检查结果,将早产儿分为宫内炎症阳性组和阴性组。采用Ficoll密度梯度离心法和贴壁黏附法分别获得脐血单个核细胞以及单核细胞。用内毒素(LPS,100 ng/ml)刺激单个核细胞12 h后,流式细胞术(PCR)检测CD14+单核细胞HLA-DR的表达量以及CD3+CD4+/CD3+CD8+的比例。用LPS(100 ng/ml)刺激单核细胞6 h后,Real-Time PCR检测单核细胞IL-1β、IL-6、IL-10、TNF-αm RNA表达量的变化。ELISA检测脐血以及单核细胞培养上清液中IL-1β、IL-6、IL-10和TNF-α水平。结果宫内炎症阳性组脐血血浆IL-6水平高于宫内炎症阴性组,差异有统计学意义(P=0.001)。LPS刺激后,两组单核细胞IL-1β、IL-6、IL-10、TNF-αm RNA表达量及培养上清液中蛋白水平均显著升高,与刺激前比较差异均有统计学意义(P0.05);但两组间比较差异均无统计学意义(P0.05)。LPS刺激后,宫内炎症阳性组CD14+单核细胞HLA-DR表达量显著降低,而宫内炎症阴性组则显著升高,与刺激前比较差异均有统计学意义(P0.05);且阳性组HLA-DR表达量显著低于阴性组(P=0.002)。结论宫内炎症暴露并不影响早产儿脐血单核细胞对LPS的应答反应水平,但可抑制单核细胞激活后主要抗原递呈受体的表达。 相似文献
35.
This study was performed to determine the risk of family members of anti-hepatitis C virus (HCV)-positive hemophilia patients (index patients) for infection with HCV compared with the risk of acquiring hepatitis B virus (HBV), human immunodeficiency virus (HIV), and hepatitis A virus (HAV) infection. All index patients (n = 141) were found to be positive by first and second generation anti-HCV enzyme immunoassays (EIAs). Among their household contacts (n = 228), 224 were negative and 1 positive by both assays. Three contacts gave positive results in first generation anti-HCV EIA and negative results in second generation assay. This latter result was confirmed by further tests (neutralization test, synthetic peptides, and supplemental assay). Percent positivity for anti-HBc was about the same in non-sexual household contacts and sexual partners (13 of 109 [12%] and 7 of 54 [13%], respectively). Percent prevalence of anti-HBc was higher in contacts of index patients with chronic hepatitis B than in those of index patients who had recovered from that disease (6 of 20 [30%] and 14 of 133 [10%], respectively; P < .05). The HBV infection rate of contacts participating in controlled self-treatment was not higher than that of controls (3 of 57 [5%] and 10 of 98 [10%], respectively). Of 44 sexual partners, 5 (11%) were found to be positive for anti-HIV. Prevalence of anti-HAV matched with the age-related distribution in the German population. These findings suggest that intrafamilial transmission of HCV to family members of hemophilia patients is uncommon. In contacts of hemophilia patients, the risk of acquiring HBV infection seems to be as high in household contacts as in sexual contacts. Participation in controlled self-treatment does not appear to be an additional risk for HCV and HBV infection. There is no doubt that sexual transmission of HCV is less common than that of HBV and HIV. 相似文献
36.
C. C. Patterson M. Thorogood P. G. Smith M. A. Heasman J. A. Clarke J. I. Mann 《Diabetologia》1983,24(4):238-242
Summary A computer file of all Scottish hospital admissions in the period 1968–1976 was searched to identify the 2,505 children (aged < 19 years) with a diagnosis of diabetes. The average annual incidence of the disease (based on first hospital admission) was estimated to be 13.8 per 100,000 children aged < 19 years (boys 14.4 per 100,000; girls 13.2 per 100,000). The highest incidence, 20.0 per 100,000 was in the age group 10–14 years and the lowest 7.1 per 100,000 in those aged < 5 years. It is estimated that during the study period there was an 80% increase in the annual incidence of juvenile diabetes, from about 10 per 100,000 in 1968 to about 18 per 100,000 in 1976. First admission rates showed seasonal variations for those aged 5 years or more, with peaks in October/November and January/February. Marked variation was found in the incidence rates in the different counties of Scotland. The central lowlands which includes the cities of Edinburgh and Glasgow was an area of low incidence. There appeared to be an inverse correlation between the incidence rate in each county and population density. In Glasgow, there was an inverse association between the incidence rate in each city ward and the average number of persons per room. There was no evidence of space-clustering of the disease in different years within the parishes (rural districts) of each county and there was no convincing evidence that the variation in the incidence of diabetes between parishes in the same county was more than might have been expected to arise by chance. The observations are compatible with the disease having a viral aetiology but it is difficult to explain the striking rise in incidence over the study period on this basis. 相似文献
37.
38.
In two previous studies, we observed that recombinant human interleukin- 3 (IL-3) induced an increase in marrow burst-forming unit-erythroid- derived colonies in vitro in some patients with Diamond-Blackfan anemia (DBA). To determine whether a similar erythropoietic response could be induced in vivo, we treated 13 patients with DBA (aged 4 to 19 years) with two preparations of IL-3. All patients had absent absolute reticulocyte counts and markedly reduced to absent recognizable bone marrow erythroid elements; patients with circulating reticulocytes in the previous 12 months were excluded from study. All patients except 1 had failed steroid therapy and had been transfusion-dependent since infancy; 1 patient was maintained on high-dose prednisone at the time of enrollment. On the first arm of the study, IL-3 (Immunex Corp, Seattle, WA) was administered subcutaneously using a dose escalation regimen of 125 to 500 micrograms/m2/day in divided dosage at 12-hour intervals, coadministered with 1.5 mg/kg/d of oral ferrous sulphate. Of the 13 patients that entered the trial, 4 stopped prematurely because of adverse side effects. In the other 9 evaluable cases, reticulocytes increased transiently in 1 patient from 0 to 65 x 10(9)/L after 35 days of IL-3 therapy at 250 micrograms/m2, but transfusion dependency persisted. One transient peak in absolute reticulocyte count was noted in 6 other patients, but no erythroid response was observed after completion of a full course of IL-3. Oral prednisone at 0.5 mg/kg/d was then coadministered with IL-3 at 500 micrograms/m2 to 5 of the patients without effect, and treatment was stopped. In 2 patients, a second preparation of IL-3 (Sandoz Canada Inc, Dorval, Quebec, Canada) was initiated in a dose escalation regimen of 2.5 to 10 micrograms/kg and was coadministered with ferrous sulphate. No erythroid response was observed in either patient, and in one of the two, alternate-day subcutaneous recombinant erythropoietin at 300 U/kg was administered for 3 weeks in combination with daily IL-3 at 10 micrograms/kg, but no increased erythropoiesis was seen. Significant increases in white blood cell and eosinophil counts during administration of both preparations of IL-3 were observed in all patients. These data show that the response of DBA patients to IL-3 in vivo is heterogeneous and cannot be predicted from in vitro studies. The absence of a corrective effect of IL-3 in these patients with DBA indicates that a deficiency of the cytokine is not central in the pathogenesis of the disorder. 相似文献
39.
Two alpha-globin structural mutants were mapped to their encoding loci by in vitro translation of hybrid-selected alpha 1- and alpha 2-globin mRNA. The more highly expressed mutant, alpha Spanish Town (alpha 27Val), is encoded at the alpha 2 locus and the less expressed mutant, alpha Fort de France (alpha 45Arg), is encoded at the alpha 1 locus. These results further define the distribution of alpha-globin structural mutations within the alpha-globin gene cluster and substantiate the dominant role of the alpha 2-globin locus in alpha- globin expression. 相似文献
40.
茶多酚治疗慢性酒精性肝损伤的实验研究 总被引:8,自引:0,他引:8
目的 建立酒精性肝病大鼠模型,观察茶多酚对酒精性肝病大鼠血清氨基转移酶活性和肝脏病理变化的影响,探讨茶多酚对酒精性肝损伤的防治作用。 方法 SD大鼠分成3组:酒精组(酒精7g·kg-1·d-1灌胃)、茶多酚组(酒精7g·kg-1·d-1 茶多酚0.25g·kg-1·d-1灌胃)和对照组(等渗盐水灌胃)。各组分别于4周末、12周末和24周末处死大鼠留取肝脏标本,用于HE染色和Masson染色。 结果 酒精组大鼠血清氧基转移酶水平较对照组升高,茶多酚组大鼠与酒精组相比,其值有明显降低,差异有统计学意义(P<0.05)。HE染色显示酒精组大鼠肝细胞浆出现不同程度的脂肪变性,小叶各带可见不同程度的点、灶状或片状坏死,24周大鼠可见桥接坏死。Masson三色染色可见24周大鼠汇管区边缘有绿染胶原纤维包绕增生,肝窦中可见绿染胶原纤维分布。茶多酚组肝脂肪变和炎症程度轻于酒精组,未发现桥接坏死。 结论 茶多酚对酒精性肝损伤具有一定的保护作用。 相似文献