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31.
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   
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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   
34.
Cash  FE; Monplaisir  N; Goossens  M; Liebhaber  SA 《Blood》1989,74(2):833-835
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   
35.
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   
36.

Objectives

Sumac (Rhus coriaria L.) is widely used spice which has several properties such as antioxidant, anti-inflammatory and antimicrobial. The purpose of this animal study was to evaluate the effects of sumac extract on levels of receptor activator of nuclear factor-kappa B ligand (RANKL), osteoprotegerin (OPG) expression, serum oxidative status, and alveolar bone loss in experimental periodontitis.

Material and Methods

Twenty-four Wistar rats were separated into three groups: non-ligated (NL, n=8), ligature only (LO, n=8), and ligature and treated with sumac extract (S, n=8) (20 mg/kg per day for 11 days). A 4/0 silk suture was placed around the mandibular right first molars subgingivally; after 11 days, the rats were sacrificed, and alveolar bone loss was histometrically measured. The detection of RANKL and OPG were immunohistochemically performed. Levels of serum total antioxidant status (TAS)/total oxidant status (TOS), and oxidative stress index (OSI) were also analyzed.

Results

Alveolar bone loss was significantly greater in the LO group compared to the S and NL groups (p<0.05). The number of inflammatory cell infiltrate (ICI) and osteoclasts in the LO group was significantly higher than that of the NL and S groups (p<0.05). The number of osteoblasts in the LO and S groups was significantly higher than that of the NL group (p<0.05). There were significantly more RANKL-positive cells in the LO group than in the S and NL groups (p<0.05). OPG-positive cells were higher in S group than in LO and NL groups (p<0.05). TOS and OSI levels were significantly reduced in S group compared to LO group (P<0.05) and TAS levels were similar in S and NL group (p>0.05).

Conclusions

The present study showed that systemic administration of sumac extract may reduce alveolar bone loss by affecting RANKL/OPG balance, TOS and OSI levels in periodontal disease in rats.  相似文献   
37.
目的:评价肾交感神经刺激(Renal sympathetic nerves stimulation,RSNS)对全身交感神经系统的影响。方法12只成年杂种犬随机分为两组:假手术组(Sham组,n=6)和肾交感神经刺激组(RSNS组,n=6)。RSNS组经左肾动脉外膜给予持续2 h高频电刺激,刺激参数:频率20 Hz,脉宽0.1 ms,刺激强度随血压进行调整,以保持血压较刺激前升高10%;假手术组在左肾动脉附近寻找一处体表皮肤给予以同样2 h高频电刺激。分别于基础状态和2 h刺激末检测血压(BP)、心率(HR)、心率变异性(HRV)和血清去甲肾上腺素(NE)浓度。结果与基础状态比较,Sham组成年杂种犬2 h末BR、HR、交感神经活性和血清去甲肾上腺素浓度比较差异均无统计学意义(P>0.05)。与基础状态比较,RSNS可以明显提高成年杂种犬BR、交感神经活性和血清去甲肾上腺素浓度,差异有统计学意义(P<0.05)。结论肾交感神经刺激可以明显提高全身交感神经系统活性。  相似文献   
38.
甲状腺术后瘢痕组织是甲状腺局部分切除术后由于手术方式及缝线填充而形成的组织,甲状腺术后瘢痕组织形成及其发生发展过程同一般的组织损伤修复病理过程一样,为渐进老化阶段的结缔组织,其内小血管稀少,胶原纤维增多[1]。由于甲状腺术后瘢痕组织其质地较硬,活动性差,超声声像图上表现缺乏典型特征,与癌灶极其相似,因此鉴别较困难。本文将介绍超声对于甲状腺术后的随诊应用,分析甲状腺术后瘢痕组织的超声检查特点并着重介绍超声动态观察甲状腺术后瘢痕组织的应用及其发展前景。  相似文献   
39.
40.
Advances in digital technology in the last decades have led to a fast development of ultrasound technology. Ultrasound information originating from stationary structures or red blood cells moving into the vessels can be visualized with different imaging modalities. Conventional B-mode sonography provides anatomical details based on acoustic impedance differences. Gray-scale sonography represents the structural echoes as brightness points. Based on the Doppler effect, vascular scattering can be represented as spectral wave velocity depending on time (velocity/time curve), or as dual-scale color mapping depending on the changes in average blood velocity. The flow-in is depicted in red and the flow-out in blue. The analysis of the vascular scattering enhanced by infusion of contrast agents is the basis of contrast-enhanced harmonic imaging. The perfusional pattern of tissues allows the differential diagnosis of expansive lesions. Tissue strain analysis provides a new dimension of diagnostic information. It is used in elastographic imaging to describe relative physical tissue stiffness properties. Tissue stiffness information is complementary to and independent of the acoustic impedance information provided by B-mode imaging as well as the vascular flow information provided by Doppler imaging. Adjacent tissue elements may appear identical using conventional B-mode or Doppler imaging. When stress (axial force) is applied to tissues, they show different degrees of deformation. Comparing the baseline and stress image information, each tissue element may be labeled by its relative stiffness. A lighter shade indicates relatively soft tissue (elastic), while a darker shade indicates relatively stiff tissue (non-elastic).  相似文献   
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