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991.
Elevated serum immunoglobulin E (IgE) and increased prevalence of atopy is reported in patients infected with human immunodeficiency virus (HIV). The elevated serum IgE may be attributed to polyclonal stimulation of B cells or IgE production against allergens, viruses, fungi and bacteria. This study investigates the prevalence of atopy in perinatally HIV-infected children, and the relationships between serum IgE (and other serum immunoglobulins) with atopy, CD4+ cell count and HIV-disease stage. Serum immunoglobulin levels, epicutaneous skin test for common aeroallergens, clinical Centers for Disease Control and Prevention (CDC) classification, CD4+ cell counts and allergy history were extracted from the charts of perinatally HIV-infected children on highly active antiretroviral therapy. The prevalence of atopy (52%) and the pattern of aeroallergen sensitivity were comparable with the US pediatric population. Serum IgE levels did not correlate with clinical disease stage. However, in non-atopic patients, serum IgE levels increased with disease progression (p = 0.02). There was an inverse relationship between the prevalence of elevated serum IgE levels and atopy with progression of disease (p = 0.019). Serum IgE did not correlate with atopy, CD4+ cell count, or duration of HIV infection or levels of serum immunoglobulins. This is the first study to show no increased prevalence of atopy in perinatally HIV-infected children compared with the general population. In advanced stages of HIV, elevated serum IgE may be specific for antigens other than those known as allergens.  相似文献   
992.
Abstract: Recently, successful results of ulcerative colitis (UC) treatments with leukocyte apheresis have been reported by several institutes. To certify the efficacy of leukocyte apheresis in refractory UC patients, a multicenter open label trial was conducted, and results were analyzed. Fifty patients diagnosed with active steroid‐resistant UC were enrolled in this study from 14 medical centers. Using a centrifugal cell separator (Component Collection System, Haemonetics), leukocyte apheresis was performed once a week for 5 weeks. General conditions and abdominal symptoms were recorded daily, and laboratory tests were followed weekly. Changes of colonoscopic and histological manifestations of luminal activity through the study period were evaluated. At the end of the study period, stool frequency was decreased to less than 4 times a day in 68.4% (26 of 38) and serum C‐reactive protein (CRP) concentration was normalized in 56.7% (17 of 30) of the patients. Colonoscopic remission was achieved in 57.7% (26 of 45), and histological improvement was noted in 54.1% (20 of 37) of the patients tested. Improved disease activity was demonstrated in 74% (37 of 50) of the patients by general assessment criteria. Analysis of the trial data confirmed the valid clinical efficacy of leukocyte apheresis by centrifugal cell separator in refractory UC patients.  相似文献   
993.
SUMMARY: Inhibition of mevalonate synthesis by several statins has been shown to suppress DNA synthesis in glomerular mesangial cells. In the present study, we investigated the effect of a new statin, cerivastatin, on fetal calf serum (FCS)-induced DNA synthesis of cultured rat mesangial cells. Cultured rat mesangial cells were stimulated by 10% FCS in the presence or absence of cerivastatin and mevalonate. 5-bromo-2-deoxyuridine (BrdU) incorporation was used to assess DNA synthesis. the present study showed that 10% FCS caused marked stimulation of DNA synthesis in the mesangial cells. Cerivastatin inhibited FCS-stimulated BrdU incorporation in a dose-dependent manner. IC50 was approximately 1 umol/L. Exogenous mevalonate, farnesyl pyrophosphate and geranylgeranyl pyrophosphate significantly prevented the inhibitory effect of cerivastatin on DNA replication. It appears that cerivastatin, by inhibiting the synthesis of mevalonate, may suppress DNA synthesis in the mesangial cells.  相似文献   
994.
目的:探讨门静脉转流对肝硬化大鼠耐受人肝血流阻断时限的影响。方法:观测门静脉转流与非门静脉转流条件下阻断入肝血流不同时程后动物存活率及肝脏能量代谢的变化,包括肝细胞线粒体呼吸控制率(RCR)、肝组织三磷酸腺苷(ATP)含量、动脉血酮体比值(AKBR)。结果:①术后两周存活率:肝硬化大鼠门静脉转流下入肝血流阻断(PBB)-30min组和PBB-45min组为100%,单纯入肝血流阻断(PTC)-30min组、PBB-60min组分别为65%和75%。②肝脏能量代谢:缺血后肝组织ATP、RCR及AKBR均明显下降。再灌注后上述指标逐渐恢复,但随缺血时间延长,升高幅度明显降低,甚至难以恢复。结论:门静脉转流能显著提高肝硬化大鼠常温下耐受入肝血流阻断的时限。  相似文献   
995.
大鼠睾丸间质细胞分离及其鉴定   总被引:9,自引:1,他引:8  
目的和方法 :通过血管冲洗、Ⅱ型胶原酶消化以及Percoll梯度离心 ,建立大鼠睾丸间质细胞分离方法。结果 :(1)Percoll密度梯度离心后纯化的间质细胞 3β HSD染色阳性百分率可达 85 %。 (2 ) 1.2× 10 -3 IU/mlhCG可显著性增加间质细胞睾酮的分泌 (P <0 .0 5 )。结论 :提示该方法可靠且具有一定应用前景  相似文献   
996.
白丽  竺清渝 《北京医学》2002,24(4):244-246
目的探讨血压正常老年患者和老年高血压患者24h动态血压波动规律及与靶器官损害的关系.方法采用无创伤袖带式动态血压监测仪检测36例中年人(对照组),50例血压正常老年患者,60例老年高血压患者的动态血压.结果血压正常老年患者较中年血压正常者24h动态血压呈杓型曲线的比例明显下降.血压正常老年患者,血压昼夜波动曲线与心、脑、肾损害无相关性.老年高血压患者,血压曲线呈非杓型者比例增高,血压昼夜节律消失较节律正常的高血压患者有更显著的靶器官损害.结论对于非高血压患者,随年龄的增加,血压昼夜节律消失者增多,血压曲线变化与心、脑、肾损害无关,可能与原发病有关.对于高血压患者,血压昼夜节律紊乱可作为靶器官损害的预测因子.  相似文献   
997.
去白细胞输血预防非溶血性发热性输血反应的临床应用   总被引:14,自引:5,他引:9  
目的:评价临床输注法去白细胞红细胞悬液和浓缩血小板预防非溶血性发热性输血反应(FNHTR)的效果。方法:选择100例肝硬化、胃溃疡和胃癌等病人输注去白细胞红细胞悬液,对照组相类似50例病人输注普通红细胞悬液。240例急慢性白血病、再生障碍性贫血、多发性骨髓瘤、血小板减少性紫癜、糖尿病、肝硬化、上消化道出血、重症肝炎、烧伤、癌症放、化疗等患者分为两组,各组120例随机接受去白细胞血小板或未去白细胞血小板悬液。观察这些患者FNHTR的发生率。结果:在100例接受去白细胞红细胞悬液的患者中未发生FNHTR,对照组50例患者中有8例发生FNHTR,发生率为16%;血小板输注的患者中,去白细胞和未去白细胞的FNHTR发生7例和25例,发生率分别为5.83%和20.83%。结论:去白细胞输血可防止或减低FNHTR的发生。  相似文献   
998.
Low density lipoprotein (LDL) has been found to represent a suitable carrier for cytotoxic drugs that may target them to cancer. This study investigated whether very low density lipoprotein (VLDL), LDL and high density lipoprotein (HDL) can be used to effectively incorporate four cytotoxic drugs, 5-fluorouracil (5-FU), 5-iododeoxyuridine (IUdR), doxorubicin (Dox) and vindesine; characterized the complexes; and examined the effect of incorporation on drug cytotoxicity against HeLa cervical and MCF-7 breast carcinoma cells. Significant drug loading was achieved into all three classes of lipoproteins, consistent with the sizes and hydrophobicity of the drugs. The relative loading efficiency was found to be vindesine>IUdR>Dox>5-FU for all three classes of lipoproteins. As shown by electron microscopy (EM), drug incorporation did not affect the size or morphology of the lipoproteins. Differential scanning calorimetry (DSC) showed that drug loading did not significantly change the thermal transition temperature of core lipids in the lipoproteins. The transition enthalpy was changed only for LDL–Dox and LDL–vindesine. The drugs remained stable in the lipoproteins as determined by high performance liquid chromatography (HPLC). EM, DSC and HPLC data suggest that drugs were incorporated into lipoproteins without disrupting their integrity and drugs remained in their stable forms inside lipoproteins. Compared with free drugs in cytotoxicity assays, the IC50 values of LDL– and HDL–drug complexes were significantly lower (2.4- to 8.6-fold for LDL complexes and 2.5- to 23-fold for HDL complexes). All free or lipoprotein-bound drug formulations were comparably more cytotoxic against MCF-7 than HeLa cells. Upregulating the lipoprotein receptors enhanced, and downregulating them inhibited, the cytotoxicity, indicating the mechanistic involvement of lipoprotein receptor pathways. Complexes of all four drugs with VLDL, in contrast to LDL and HDL, had the same cytotoxicity as the four corresponding free drugs. Our results suggest that further studies are required of the potential of HDL to be a cancer targeting drug carrier.  相似文献   
999.
灯盏花素合力源精纯溶栓酶治疗不稳定型心绞痛30例   总被引:11,自引:5,他引:6  
目的 :观察灯盏花素、力源精纯溶栓酶治疗不稳定型心绞痛 (UAP)的临床疗效。方法 :将 6 0例 UAP患者随机分为治疗组和对照组各 30例。治疗组给予灯盏花素、力源精纯溶酶加常规抗心绞痛治疗 ;对照组仅给予常规抗心绞痛治疗。分别观察 2组治疗前后的心绞痛发作及硝酸甘油用量的变化 ,检测静息心电图和血液流变学指标。结果 :治疗组在缓解心绞痛总有效率 (93.33% )、改善异常心电图及血液流变学指标、降低硝酸甘油用量〔(0 .4 5± 0 .15 ) m g/ d〕等方面均显著优于对照组。结论 :灯盏花素联合力源精纯溶栓酶治疗 U AP疗效优于常规西药治疗。  相似文献   
1000.
探讨荧光原位杂交法(FISH)对母血中胎儿有核红细胞(NRBC)进行无创性产前诊断的可行性。20例孕龄15-20周的孕妇外周血经不连续密度梯度离心、制片、显微镜下识别并共计数NRBC及定位,然后行Y染色体的FISH检测。结果发现10例孕男性胎儿的孕妇外周血细胞涂片中每例均有阳性杂交信号出现;阳性率为60%(24/40)。10例孕女性胎儿的孕妇外周血细胞涂片中1例出现阳性杂交信号;阴性率为95%(38/40),假阳性率仅为5%(2/40)。结果提示FISH法对于用母血中分离到的胎儿细胞进行染色体异常的无创性产前遗传学检查具有重要意义。  相似文献   
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