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931.
Cytomegalovirus (CMV) infection is a common opportunistic systemic infection in immunocompromised patients, but skin involvement is rare. Herein, we report a 10 year-old girl from consanguineous parents who was referred to our center because of disseminated maculopapular rash. She had history of upper and lower respiratory tract infections. In immunological studies, increased serum IgE level and decreased responses to tetanus and diphtheria were detected. Polymerase chain reaction (PCR) examination of bronchoalveolar lavage and serum sample revealed the presence of CMV. Early diagnosis of cutaneous CMV and appropriate treatment are the key actions in management of patients with underlying immunodeficiencies to avoid further complications.  相似文献   
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Stiff person syndrome (SPS) is a rare disorder, characterised by fluctuating rigidity and stiffness of the axial and proximal lower limb muscles, with superimposed painful spasms and continuous motor unit activity on electromyography. Although rare in general neurology practice, once observed it is unforgettable. The general neurologist may see only one or two cases during his or her career and as such it remains underdiagnosed. Left untreated, SPS symptoms can progress to cause significant disability. Patients have a poor quality of life and an excess rate of comorbidity and mortality. The severity of symptoms and lack of public awareness of the condition create anxiety and uncertainty for people with the disease. This review aims to raise awareness of SPS and to improve the likelihood of its earlier diagnosis and treatment.  相似文献   
934.
Natalizumab interferes with immune cell migration into the central nervous system via blocking the alpha-4 subunit of very-late activation antigen-4 (VLA-4). Occurrence of rare but serious progressive multifocal leukoencephalopathy during prolonged natalizumab therapy of multiple sclerosis (MS) calls for a more detailed understanding of potential coeffects. We longitudinally studied alpha-4 and beta-1 surface levels on blood cells from 18 MS patients by flow cytometry. Expectedly, detectability of natalizumab-blocked alpha-4 was diminished on all investigated cell subsets. In addition, we report a concurrent and significant decrease of beta-1 surface levels on T-cells, B-cells, natural killer cells, and natural killer T cells, but not on monocytes. Uncovering secondary effects of natalizumab is mandatory to increase safety in MS therapy.  相似文献   
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There is a great need for rapid screening methods that detect essentially all mutations. Dideoxy fingerprinting (ddF) is a highly sensitive screening method that is performed by electrophoresing one lane of a Sanger dideoxy termination reaction through a nondenaturing gel. Mutations may produce an extra segment or eliminate a segment from the termination products (informative dideoxy component). In addition, mutations can be detected by the altered mobility of one or more termination segments (informative SSCP component). To screen larger segments with virtually 100% sensitivity, bi-directional ddF (Bi-ddF) was developed. Bi-ddF is a 'second generation ddF' in which the dideoxy termination reaction is performed simultaneously with two opposing primers. Bi-ddF has two important advantages over ddF: (i) the dideoxy component can detect 10 of the 12 types of possible single-base substitutions; and (ii) the SSCP component is enhanced because alterations of mobility can be detected in either the downstream or upstream direction. As a result, Bi-ddF can screen larger regions of genomic DNA with virtually 100% sensitivity. Bi-ddF detected 100% of 28 single-base substitutions in a 494 bp segment containing exons B and C of the human factor IX gene and 100% of 42 single-base substitutions and one microdeletion present in a 577 bp region containing exon H. In a blinded analysis in which 39 wildtype samples were randomly mixed with 51 mutant samples, all mutations were detected with no false positives. Bi-ddF requires essentially the same effort as ddF, yet twofold more DNA sequence can be screened reliably per unit effort.   相似文献   
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939.
谷氨酸脱羧酶抑制剂L-苹果酸对小鼠学习记忆的影响   总被引:3,自引:0,他引:3  
跳台法和Y迷宫法试验表明,小鼠poL-苹果酸600mg·kg-1连续5d后对记忆的获得、巩固和再现均有明显的改善作用,并能促进空间辨别学习能力;L-苹果酸改善记忆的作用能被NMDA受体桔抗剂氯胺酮所桔抗。脑内游离氨基酸测定显示,L-苹果酸可明显降低小鼠脑内GABA水平,提高Glu/GABA比值。实验结果表明,脑内GABA水平下降,Glu/GanA比值升高对学习记忆有正性调节作用。  相似文献   
940.
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