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131.
大鼠肺内NOS阳性神经及其来源的研究   总被引:1,自引:1,他引:0  
应用还原型尼可酰胺腺嘌呤二核苷酸磷酸硫辛酰胺脱氢酶(NADPHd)组织化学技术和HRP逆行追踪与NADPHd组化结合法,对大鼠肺内一氧化氮合酶(NOS)阳性神经及其来源进行了研究。结果证实,肺内支气管和肺血管存在不同密度的NOS阳性神经纤维,肺内神经节中存在少量NOS阳性神经细胞。用HRP与NADPHd结合法,在迷走神经结状节和胸。。脊神经节中发现HRP-NOS双标记细胞,说明肺内NOS神经纤维部分来自结状节和脊神经节,并对此进行了讨论。  相似文献   
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A man with only yellowing of the skin and eye sclera was diagnosed with clonorchiasis, which rarely manifested jaundice as the initial symptom. However, because of a lack of evidence for a diagnostic gold standard, the time until definitive diagnosis was more than a week. The diagnostic process relied on inquiring about the patient’s history, including the place of residence, dietary habits, and symptoms, as well as on serological findings, an imaging examination, and pathological findings. MRCP and CT results showed mild dilatation of intrahepatic ducts and increased periductal echogenicity. The eggs were ultimately found in stool by water sedimentation method after the negative report through direct smear. DNA sequencing of PCR production of the eggs demonstrated 98-100% homology with ITS2 of Clonorchis sinensis. After anti-parasite medical treatment, the patient’s symptoms were gradually relieved. Throughout the diagnostic procedure, besides routine examinations, the sedimentation method or concentration method could be used as a sensitive way for both light and heavy C. sinensis infection in the definite diagnosis.  相似文献   
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Death receptor 5 (DR5)-induced apoptosis that prioritizes the death of tumor cells has been proposed as one of the promising cancer therapies. In this process, oligomerized DR5 death domain (DD) binding to Fas-associated death domain (FADD) leads to FADD activating caspase-8, which marks the formation of the death-inducing signaling complex (DISC) that initiates apoptosis. DR5 DD mutations found in cancer cells have been suggested to play an important pathological role, the mechanism through which those mutants prevent the DR5-activated DISC formation is not clear yet. This study sought to provide structural and molecular insight for the roles of four selected DR5 DD mutations (E355K, E367K, K415N, and L363F) in the oligomerization of DR5 DD–FADD complex during the DISC formation. Results from the molecular dynamics simulations show that the simulated mutants induce conformational, dynamical motions and interactions changes in the DR5 DD–FADD tetramer complex, including changes in a protein’s backbone flexibility, less exposure of FADD DED’s caspase-8 binding site, reduced H-bonding and hydrophobic contacts at the DR5 DD–FADD DD binding, altered distribution of the electrostatic potentials and correlated motions of residues, and reduced binding affinity of DR5 DD binding to FADD. This study provides structural and molecular insight for the influence of DR5 DD mutations on oligomerization of DR5 DD–FADD complex, which is expected to foster understanding of the DR5 DD mutants’ resistance mechanism against DR5-activated DISC formation.  相似文献   
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以芥菜型油菜(Brcssica juncea)下胚轴来源的愈伤组织为材料,进行悬浮细胞振荡培养,得到游离的单细胞。这些细胞作浅层液体静置培养,可获得高频率的愈伤组织。在附加有水解乳蛋白200毫克/升、BA 2—3毫克/升及GA,0.1—1毫克/升的MS培养基上,这些愈伤组织分化了芽。分化的芽在无激素或附加有0.01—0.1毫克/升IAA或NAA的MS培养基上长出根,从而发育成完整植株。当对游离细胞获得的再生植株的茎切段愈伤组织,再经上述程序进行细胞培养时,发现愈伤组织诱导率及愈伤组织分化频率均远远高于原供体,从而建立了B.juncea易再生的体细胞无性系。  相似文献   
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The importance of the epidermal permeability barrier (EPB) in protecting the mammalian species against harmful UV irradiation, microorganism invasion and water loss is well recognized, as is the role of calcium (Ca(2+)) in keratinocyte differentiation, cell-cell contact and the EPB. In a previous study, we reported that the overexpression of the Ca(2+)-sensing receptor (CaSR) in the undifferentiated basal cells of the epidermis induced a modified epidermal differentiation program including an accelerated EPB formation in transgenic mice, suggesting a role for CaSR signaling in the differentiation of embryonic epidermal cells during development. We now describe the expression profile of claudins (Cldns) and keratin markers in the accelerated EPB formation of K14-CaSR transgenic mice during development as compared to the wild type from E12.5 to newborn stages. Our data show that the transgenic epidermis undergoes an advanced epidermal differentiation program as compared to the wild type as evidenced morphologically as well as by the expression of K14, K1, loricrin, Cldn6, Cldn18 and Cldn11. In addition, we report for the first time the sequential expression of Cldns in epidermal development and describe that the localization of some Cldns change within the epidermis as it matures. Furthermore, we demonstrate that Cldn6 is expressed very early in epidermal morphogenesis, followed by Cldn18, Cldn11 and Cldn1.  相似文献   
139.
Ma X  Liu Y  Gowen BB  Graviss EA  Clark AG  Musser JM 《PloS one》2007,2(12):e1318
Tuberculosis (TB) is the leading cause of death worldwide due to an infectious agent. Data have accumulated over decades suggesting that variability in human susceptibility to TB disease has a genetic component. Toll-like receptors (TLRs) play a critical role in initiating the innate immune response to many pathogens in mouse models, but little is known about their role in human infections. Human TLRs have been reported to recognize mycobacterial antigens and initiate an immune response. We tested the hypothesis that amino acid-altering polymorphisms in five TLRs were associated with susceptibility to TB disease using a population-based case-control study with 1,312 adult TB patients and controls. Full-coding region sequencing of the five TLR genes in all 1,312 subjects yielded a data set in excess of 16 Mb. Rare nonsynonymous polymorphisms in TLR6-TLR1-TLR10 were significantly overrepresented among African-American TB cases compared with ethnically-matched control subjects. Common nonsynonymous polymorphisms in TLR6-TLR1-TLR10 also were significantly associated with TB disease in certain ethnic groups. Among African Americans, homozygotes for the common-variant haplotype TLR1-248S, TLR1-602I, and TLR6-249S had a significantly increased TB disease risk. A transmission/disequilibrium test on an independent sample found that the TLR1-248S variant was preferentially transmitted to diseased children, thereby confirming disease association. These results are consistent with recent reports implicating TLR1 variants, including TLR1-602, in significantly altered innate immune responses. Also consistent with disease association, rare TLR6 variants were defective in their ability to mediate NF-kappaB signal transduction in transfected human cells. Taken together, the data suggest that variant TLRs contribute to human susceptibility to TB disease. Extensive full-exon resequencing was critical for revealing new information about the role of TLRs in human-pathogen interactions and the genetic basis of innate immune function.  相似文献   
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