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321.
322.
Conservation of myeloid surface antigens on primate granulocytes   总被引:10,自引:0,他引:10  
Monoclonal antibodies reactive with myeloid cell surface antigens were used to study evolutionary changes in granulocyte surface antigens from primate species. Certain of these granulocyte membrane antigens are conserved in phylogenetically distant species, indicating the potential functional importance of these structures. The degree of conservation of these antigens reflects the phylogenetic relationship between primate species. Furthermore, species of the same genus show similar patterns of binding to this panel of anti-human myeloid antibodies. This finding of conserved granulocyte surface antigens suggests that non-human primates may provide a model system for exploring uses of monoclonal antibodies in the treatment of human myeloid disorders.  相似文献   
323.
Previous studies have demonstrated that significant hematologic improvement occurs in the majority of patients with hairy cell leukemia (HCL) treated with partially purified or recombinant interferon (IFN). Fifty-three patients received IFN alfa-2b for at least 3 months in a dose of 2 X 10(6) U/m2 subcutaneously thrice weekly. Of the 49 patients evaluable for response (at least 6 months of IFN therapy), there were ten complete responses and 29 partial responses for a total response rate of 80%. The peripheral blood counts and bone marrow continued to improve over the course of a full year of therapy. IFN was well tolerated, with no patients discontinuing therapy because of toxicity. Transient myelosuppression occurred in most patients during the first 1 to 2 months of therapy, occasionally precipitating a transfusion requirement. After IFN treatment was discontinued, there was a marked decrease in normal marrow elements and a relative increase in marrow hairy cells. This was associated with a transient increase in normal elements in the peripheral blood. Only one of 24 patients followed after receiving IFN for a median of 8.5 months (range, 3 to 16 months) has required further therapy. We conclude that low-dose IFN alfa-2b is highly effective in advanced HCL; responding patients should be treated for at least 1 year. The decision to initiate a second course of IFN therapy should be based primarily on peripheral blood counts and the clinical status of the patient rather than on the bone marrow.  相似文献   
324.
Olivieri  NF; Chang  LS; Poon  AO; Michelson  AM; Orkin  SH 《Blood》1987,70(3):729-732
The molecular basis of hemoglobin H disease in a Black family of Canadian origin was investigated. Affected individuals had a combination of deletion and nondeletion alpha-thalassemia mutations on different chromosomes. Cloning and sequencing of the DNA of one member with the nondeletion form revealed a new thalassemia mutation, an A---- G substitution, in the initiation codon of the remaining alpha-globin gene of a rightward (-alpha 3.7) deletion chromosome. This mutation abolished an Ncol restriction site and therefore is detectable in genomic DNA by Southern blot analysis.  相似文献   
325.
Disorders of sex development (DSDs) encompass a broad spectrum of conditions affecting the development of the gonads and genitalia. The underlying causes for DSDs include gain or loss of function variants in genes responsible for gonad development or steroidogenesis. Most patients with DSD have an unknown genetic etiology and cannot be given an accurate diagnosis. We used whole exome capture and massively parallel sequencing to analyse a large family with 46,XY DSD and 46,XX premature ovarian insufficiency. In addition, we used a recently developed method for linkage analysis using genotypes extracted from the MPS data. This approach identified a unique linkage peak on chromosome 9 and a novel, 3 bp, in-frame deletion in exon six of NR5A1 (steroidogenic factor-1 or SF1) in all affected individuals. We confirmed that the variant disrupts the SF1 protein and its ability to bind and regulate downstream genes. NR5A1 has key roles at multiple points in gonad development and steroidogenic pathways. The variant described here affects the function of SF1 in early testis development and later ovarian function, ultimately leading to the 46,XY DSD and 46,XX premature ovarian insufficiency phenotypes, respectively. This study shows that even at low coverage, whole exome sequencing, when combined with linkage analysis, can be a powerful tool to identify rapidly the disease-causing variant in large pedigrees.  相似文献   
326.

Background

Toxoplasma gondii can infect all warm-blooded animals. Modified agglutination test (MAT) and ELISA are widely used for the detection of T. gondii antibodies. However, there is little information on their acceptability for detecting antibodies in companion animals.

Methods

This study compared ELISA and MAT for their ability to detect T. gondii infection in naturally infected dogs and cats. Blood samples were collected from dogs and cats in different areas of Beijing, China and analyzed by ELISA and MAT. The χ2 test and κ analysis were used to evaluate their efficiency and agreement.

Results

For dogs, the seroprevalence of T. gondii antibodies detected by ELISA was 34.7%, which was significantly higher than that detected by MAT (P<0.05). There was no significant difference between ELISA and MAT for detecting T. gondii antibodies in cats. Good agreements between MAT and ELISA were seen in both dogs and cats; however, inconsistent results were demonstrated by κ analysis and in MAT titer assay.

Conclusion

Serum-based ELISA may be more satisfactory for screening test of T. gondii infection in dogs, whereas both methods could be acceptable in cats.  相似文献   
327.
Long-term treatment of lupus nephritis with cyclosporin A   总被引:9,自引:0,他引:9  
We evaluated the efficacy and safety of long-term treatment with cyclosporin A (CSA) in type IV lupus nephritis. Seventeen patients with biopsy-proven WHO type IV lupus nephritis were enrolled in a prospective, open study. Twelve of the 17 completed 48 months of treatment with CSA and prednisolone. Three patients required the addition of azathioprine, at 12, 38 and 47 months, respectively, for cutaneous disease flare with refractory rashes. One patient was lost to follow-up at 40 months. The mean +/- SD duration of treatment was 43.2 +/- 10.1 months (range 15.7-48 months). A significant reduction of proteinuria and a significant rise in serum albumin were noted 1 month after initiation of treatment. Improvement was maintained throughout the study except for three patients who relapsed with recurrence of nephrotic syndrome. There were no significant changes in serum creatinine level or creatinine clearances throughout the study. Repeat renal biopsy at 12 months following treatment with CSA showed histological improvement, with WHO type II changes in all 17 patients accompanying significant reduction in activity indices. Patients with baseline haemoglobin (Hgb) levels < 12 g/dl showed significant improvement. Serum C3 and C4 levels were not changed significantly. Corticosteroid-sparing effects were noted. Side-effects included hypertension, gum hypertrophy and mild hirsuitism, but were not serious. Combination therapy using CSA and prednisone is effective and safe for long-term treatment in lupus patients with WHO type IV nephritis.   相似文献   
328.
目的:脐血处理的关键问题是提高干细胞的回收率及实现处理过程的标准化和可重复化,实验对此进行探讨,比较干细胞分离仪与传统羟乙基淀粉手工法分离脐血的效果。方法:实验于2006-12/2007-05在广州医学院附属市一人民医院完成。①脐血来源:39份脐血采自广州医学院附属市一人命医院妇产科健康顺产新生儿脐带,产妇均知情同意。随机数字表法分为仪器分离组17份、手工分离组22份。②实验方法:仪器分离组收集脐血称质量,计算体积,在开始处理前20min缓慢加入相当于20%脐血体积的60g/L羟乙基淀粉。仪器分离组按仪器要求自动分离,分离终体积20mL。手工分离组50g离心5min,压浆板压出全部血浆以及18mL红细胞移至无菌空袋,500g离心13min,自动压浆板压出血浆,保留20mL终体积样本。③实验评估:采用全自动计数仪进行检测有核细胞(白细胞)、红细胞数量。流式细胞仪分析CD34 含量。结果:采用干细胞分离仪处理浓缩脐血,有核细胞回收率为(89.7±3.4)%,CD34 细胞回收率为(98.8±5.1)%,红细胞去除率为(55.2±16.7)%,均比手工分离组分离效果好,差异有显著性意义(P<0.05或0.01)。同时,仪器分离组有核细胞回收率、CD34 细胞回收率的标准差均明显低于手工分离组(3.4vs.15.3;5.1vs.10.3)。结论:相比传统的羟乙基淀粉手工分离法,干细胞分离仪脐血分离浓缩效果理想,且结果标准误小,数据稳定。  相似文献   
329.
目的:评估减压治疗跗跖关节骨折脱位合并前足筋膜间隙综合征的疗效和前足感觉及运动功能的康复。方法:于1996-05/2003-04选择第二军医大学长征医院骨科收治的跗跖关节骨折脱位合并前足筋膜间隙综合征患者17例,利用whiteside测压装置进行前足部筋膜间隙内压监测,间隙内压>3.99kPa,均经前足背侧入路进行筋膜间隙切开减压术,同时行复位内固定恢复足的纵弓及横弓。固定48h后,进行功能康复训练,主、被动地活动前足各关节及短波红外线治疗。结果:术后1个月进行第一次随访,前两年每3个月随访1次,以后每半年随访1次。17例患者均随访3.5以上。术后6个月随访时评估疗效,足外形正常,活动范围正常,负重行走无不适,X射线片显示正常11例;足活动轻度受限,不影响行走、工作,可进行适当的体育活动,X射线片显示跗跖关节移位<2mm4例;行走或站立过久时前足部有轻度疼痛4例,其中3例前足增宽,足弓较健侧减小,2例两点辨别觉、痛觉略减退。无一例出现前足僵硬、爪形趾、软组织萎缩及运动功能异常。结论:减压是治疗跗跖关节骨折脱位合并前足筋膜间隙综合征的有效方案,减压后应及时进行进行功能康复训练,并辅以短波红外线治疗,能有效地恢复前足感觉、运动功能。  相似文献   
330.
石斛类叶鞘的显微鉴定研究   总被引:3,自引:0,他引:3  
商品石斛的植物来源复杂,规格繁多,外形鉴定较困难。为了准确鉴定石斛的品种,对常作为药用的16种石斛属(Dendrobium Sw)植物的叶鞘进行了显微观察,发现其表皮细胞的形状,大小,所含草酸钙结晶的形状、大小、分布等种间区别较明显,可作为鉴别石斛种类的科学依据之一。本文对金钗石斛D.nobile Lindl。等16种石斛的叶鞘表面特征加以描述,并附主要特征图和检索表。  相似文献   
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