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排序方式: 共有811条查询结果,搜索用时 15 毫秒
1.
TL1A is a TNF‐like cytokine which has been shown to co‐stimulate TH1 and TH17 responses during chronic inflammation. The expression of this novel cytokine has been investigated in inflammatory disorders like rheumatoid arthritis and inflammatory bowel disease, but little is known about expression and induction in psoriasis. Indeed, the pathogenesis in psoriasis is still not fully understood and it is speculated that cytokines other than TNF‐α are important in subsets of patients. Also, for patients with severe disease that are treated with systemic anti‐TNF‐α blockade, novel candidates to be used as disease and response biomarkers are of high interest. Here, we demonstrate TL1A expression in biopsies from psoriatic lesions. Also, we investigated spontaneous and induced TL1A secretion from PBMCs and blood levels from a cohort of psoriasis patients. Here, increased spontaneous secretion from PBMCs was observed as compared to healthy controls and a small subset of patients had highly elevated TL1A in the blood. Interestingly, activation of PBMCs with various cytokines showed a decreased sensitivity for TL1A activation in psoriasis patients compared to healthy controls.TL1A levels in blood and biopsies could not be correlated with disease activity with this patient cohort. Thus, additional large‐scale studies are warranted to investigate TL1A as a biomarker.  相似文献   
2.
Evaluation of an on-line patient exposure meter in neuroradiology   总被引:1,自引:0,他引:1  
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3.
人体液中喷布洛尔及其代谢物的GC/MS分析   总被引:1,自引:0,他引:1  
用气相色谱一质谱联用(GC-MSD)系统分析方法检出了人尿中喷布洛尔的6个羟化代谢物,用Scp-Pak柱提取的方法检出了人血浆中的原型药物。并从分子结构上对此药物的代谢途径进行了研究。尿中提取和血中提取的回收率分别为90.83.%和85.88%,Gc-MSD的检测限为5pg。本方法适用于运动员兴奋剂的系统检查。  相似文献   
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X-linked spinal and bulbar muscular atrophy (SBMA) is caused by a CAG repeat expansion in the first exon of the androgen receptor (AR) gene. Disease-associated alleles (37-66 CAGs) change in length when transmitted from parents to offspring, with a significantly greater tendency to shift size when inherited paternally. As transgenic mice carrying human AR cDNAs with 45 and 66 CAG repeats do not display repeat instability, we attempted to model trinucleotide repeat instability by generating transgenic mice with yeast artificial chromosomes (YACs) carrying AR CAG repeat expansions in their genomic context. Studies of independent lines of AR YAC transgenic mice with CAG 45 alleles reveal intergenerational instability at an overall rate of approximately 10%. We also find that the 45 CAG repeat tracts are significantly more unstable with maternal transmission and as the transmitting mother ages. Of all the CAG/CTG repeat transgenic mice produced to date the AR YAC CAG 45 mice are unstable with the smallest trinucleotide repeat mutations, suggesting that the length threshold for repeat instability in the mouse may be lowered by including the appropriate flanking human DNA sequences. By sequence-tagged site content analysis and long range mapping we determined that one unstable transgenic line has integrated an approximately 70 kb segment of the AR locus due to fragmentation of the AR YAC. Identification of the cis - acting elements that permit CAG tract instability and the trans -acting factors that modulate repeat instability in the AR YAC CAG 45 mice may provide insights into the molecular basis of trinucleotide repeat instability in humans.   相似文献   
7.
N. P. Boye    O. P. Salo    N. Hyldebrandt    J. A. Wihl    A. Bevan    R. I. Harris  J. R. Lovely 《Allergy》1990,45(4):241-248
The safety and efficacy of two birch pollen extracts, one chemically conjugated to alginate (Anjuvac) the other adsorbed to aluminium hydroxide (Alutard), were investigated in an open multicentre comparative study of 63 birch pollen allergic patients. Both extracts decreased the nasal symptoms during the birch pollen season. The changes in specific IgE and IgG were much the same in both treatment groups. The adverse reactions recorded were mild in both groups, but more frequent in the Anjuvac group, probably because of a more aggressive dose schedule though there were twice as many asthmatics in the Anjuvac group. The two investigated allergen extracts were useful alternatives for immunotherapy.  相似文献   
8.
In a child with some features of Turner's syndrome, gonosomal mosaicism with an isodicentric nonfluorescent (idic)Y chromosome was detected (mos 45,X/47,X,idic(Y)(q11),idic(Y)(11)/46,X,idic(Y)(q11)). Histopathological examination showed streak gonads with some evidence of ovarian stroma and no sign of gonadoblastoma. Polymerase chain reaction (PCR) analysis in blood lymphocytes and gonadal tissues using primers of seven loci along the Y chromosome, including the sex determined region (SRY), azoospermia factor region (AZF) and the deleted in azoospermia ( DAZ ) gene was positive for all loci tested, confirming the isodicentric character of the Y chromosome and indicating the presence of the AZF region. It is remarkable that the existence of spermatogenesis controlling genes does not play an important role in gonadal development and differentiation in a phenotypic female with some Turner stigmata. The data presented here are briefly discussed with previously-described patients.  相似文献   
9.
A multiplex PCR with four primer-pairs was designed to identify the five main known SCCmec types. A clear and easily discriminated band pattern was obtained for all five types. The SCCmec type was identified for 98% of 312 clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA). SCCmec type IV was by far the most common SCCmec type among both hospital- and community-acquired MRSA isolates in Denmark.  相似文献   
10.
A method for enzyme-based in situ hybridisation of Streptococcus suis was developed. It enables the light microscopic localization of bacterial ribosomal RNA (rRNA) in formalin-fixed paraffin-embedded tissues. A unique sequence in the 16S rRNA of S. suis was targeted. Different pretreatment protocols were applied to facilitate probe penetration and multiple detection systems were tested. The results were compared to those obtained by immunohistochemistry. Pretreatment was necessary to obtain a signal by in situ hybridisation. The use of proteinase-K pretreatment was optimal regarding sensitivity and preservation of tissue morphology. A strong specific in situ hybridisation signal was achieved in tissue sections containing S. suis in microcolonies and the microanatomy of the surrounding tissue was easily assessed. However, the signal distribution differed from that found immunohistochemically and low-grade infection could not be detected by in situ hybridisation. These findings were interpreted as reflecting the physiological state of the bacteria. Thus, this method could prove useful in future studies of the infection pathogenesis.  相似文献   
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