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1.
目的:探讨280例胃食管反流病(GERD)的分布特点及危险因素。方法:对临床诊断和胃镜确诊的280例GERD患者进行临床和风险因子相关性分析。结果:不论汉族还是维族,男性患者比例均明显高于女性;汉族患者高发年龄段早于维族患者(z=-2.939,P=0.003,);汉族和维族患者占反流性食管炎和Barrett食管比例分别为42.4%、81_3%及56.5%、18.8%,其中汉族患者Barrett食管比例较高(X2=14.358,P=0.000);肥胖、习惯性便秘、重体力活动者、饮食习惯不良在维族患者中的比例较高(P〈0.001)。结论:GERD与性别、年龄密切相关,男性多于女性,汉族患者发病年龄高峰旱于维族患者;汉族患者Barrett食管发生比例高于维族患者;肥胖、习惯性便秘、重体力活动、饮食习惯不良可能是GERD尤其是维族人群GERD的危险因素。  相似文献   
2.
Although osteoporosis and its related fractures are common in patients with COPD, patients at high risk of fracture are poorly identified, and consequently, undertreated. Since there are no fracture prevention guidelines available that focus on COPD patients, we developed a clinical approach to improve the identification and treatment of COPD patients at high risk of fracture. We organised a round-table discussion with 8 clinical experts in the field of COPD and fracture prevention in the Netherlands in December 2013. The clinical experts presented a review of the literature on COPD, osteoporosis and fracture prevention. Based on the Dutch fracture prevention guideline, they developed a 5-step clinical approach for fracture prevention in COPD. Thereby, they took into account both classical risk factors for fracture (low body mass index, older age, personal and family history of fracture, immobility, smoking, alcohol intake, use of glucocorticoids and increased fall risk) and COPD-specific risk factors for fracture (severe airflow obstruction, pulmonary exacerbations and oxygen therapy). Severe COPD (defined as postbronchodilator FEV1 < 50% predicted) was added as COPD-specific risk factor to the list of classical risk factors for fracture. The 5-step clinical approach starts with case finding using clinical risk factors, followed by risk evaluation (dual energy X-ray absorptiometry and imaging of the spine), differential diagnosis, treatment and follow-up. This systematic clinical approach, which is evidence-based and easy-to-use in daily practice by pulmonologists, should contribute to optimise fracture prevention in COPD patients at high risk of fracture.  相似文献   
3.
Induction of Th1 cytokines, those associated with cell-mediated immunity, is critical for host defense against infection by intracellular pathogens, including mycobacteria. Signaling lymphocytic activation molecule (SLAM, CD150) is a transmembrane protein expressed on lymphocytes that promotes T cell proliferation and IFN-gamma production. The expression and role of SLAM in human infectious disease were investigated using leprosy as a model. We found that SLAM mRNA and protein were more strongly expressed in skin lesions of tuberculoid patients, those with measurable CMI to the pathogen, Mycobacterium leprae, compared with lepromatous patients, who have weak CMI against M. leprae. Peripheral blood T cells from tuberculoid patients showed a striking increase in the level of SLAM expression after stimulation with M. leprae, whereas the expression of SLAM on T cells from lepromatous patients show little change by M. leprae stimulation. Engagement of SLAM by an agonistic mAb up-regulated IFN-gamma production from tuberculoid patients and slightly increased the levels of IFN-gamma in lepromatous patients. In addition, IFN-gamma augmented SLAM expression on M. leprae-stimulated peripheral blood T cells from leprosy patients. Signaling through SLAM after IFN-gamma treatment of Ag-stimulated cells enhanced IFN-gamma production in lepromatous patients to the levels of tuberculoid patients. Our data suggest that the local release of IFN-gamma by M. leprae-activated T cells in tuberculoid leprosy lesions leads to up-regulation of SLAM expression. Ligation of SLAM augments IFN-gamma production in the local microenvironment, creating a positive feedback loop. Failure of T cells from lepromatous leprosy patients to produce IFN-gamma in response to M. leprae contributes to reduced expression of SLAM. Therefore, the activation of SLAM may promote the cell-mediated immune response to intracellular bacterial pathogens.  相似文献   
4.
A study of bacterial surface oligosaccharides were investigated among different strains of Neisseria gonorrhoeae to correlate structural features essential for binding to the MAb 2C7. This epitope is widely expressed and conserved in gonococcal isolates, characteristics essential to an effective candidate vaccine antigen. Sample lipooligosaccharides (LOS), was prepared by a modification of the hot phenol-water method from which de-O-acetylated LOS and oligosaccharide (OS) components were analyzed by ES-MS-CID-MS and ES-MSnin a triple quadrupole and an ion trap mass spectrometer, respectively. Previously documented natural heterogeneity was apparent from both LOS and OS preparations which was admixed with fragments induced by hydrazine and mild acid treatment. Natural heterogeneity was limited to phosphorylation and antenni extensions to the alpha-chain. Mild acid hydrolysis to release OS also hydrolyzed the beta(1-->6) glycosidic linkage of lipid A. OS structures were determined by collisional and resonance excitation combined with MS and multistep MSn which provided sequence information from both neutral loss, and nonreducing terminal fragments. A comparison of OS structures, with earlier knowledge of MAb binding, enzyme treatment, and partial acid hydrolysis indicates a generic overlapping domain for 2C7 binding. Reoccurring structural features include a Hepalpha(1-->3)Hepbeta(1-->5)KDO trisaccharide core branched on the nonreducing terminus (Hep-2) with an alpha(1-->2) linked GlcNAc (gamma-chain), and an alpha-linked lactose (beta-chain) residue. From the central heptose (Hep-1), a beta(1-->4) linked lactose (alpha-chain), moiety is required although extensions to this residue appear unnecessary.   相似文献   
5.
Tsai  CM; Chen  WH; Balakonis  PA 《Glycobiology》1998,8(4):359-365
Group B and C Neisseria meningitidis are the major cause of meningococcal disease in the United States and in Europe. N . meningitidis lipooligosaccharide (LOS), a major surface antigen, can be divided into 12 immunotypes of which L1 through L8 were found among Group B and C organisms. Groups B and C but not Group A may sialylate their LOSs with N-acetylneuraminic acid (NeuNAc) at the nonreducing end because they synthesize CMP-NeuNAc. Using sialic acid-galactose binding lectins as probes in an ELISA format, six of the eight LOS immunotypes (L2, L3, L4, L5, L7, and L8) in Groups B and C bound specifically to Maackia amurensis leukoagglutinin (MAL), which recognizes NeuNAcalpha2- 3Galbeta1-4GlcNAc/Glc sequence, but not to Sambucus nigra agglutinin, which binds NeuNAcalpha2-6Gal sequence. The combination of SDS-PAGE and MAL-blot analyses revealed that these six LOSs contained only the NeuNAcalpha2-3Galbeta1-4GlcNAc trisaccharide sequence in their 4.1 kDa LOS components, which have a common terminal lacto-N-neotetraose (LNnT, Galbeta1-4GlcNAcbeta1-3Galbeta1-4Glc) structure when nonsialylated as shown by previous studies. The LOS-lectin binding was abolished when the LOSs were treated with Newcastle disease viral neuraminidase which cleaves alpha2-->3 linked sialic acid. Methylation analysis of a representative LOS (L2) confirmed that NeuNAc is 2-->3 linked to Gal. Thus, these LOSs structurally mimic certain glycolipids, i.e., paragloboside (LNnT-ceramide) and sialylparagloboside and some glycoproteins in having LNnT and N-acetyllactosamine sequences, respectively, with or without alpha2-->3 linked NeuNAc. The molecular mimicry of the LOSs may play a role in the pathogenesis of N.meningitidis by assisting the organism to evade host immune defenses in man.   相似文献   
6.
7.

Background

This paper presents the study protocol for a pragmatic randomised controlled trial to evaluate the impact of a school based program developed to prevent teenage pregnancy. The program includes students taking care of an Infant Simulator; despite growing popularity and an increasing global presence of such programs, there is no published evidence of their long-term impact. The aim of this trial is to evaluate the Virtual Infant Parenting (VIP) program by investigating pre-conceptual health and risk behaviours, teen pregnancy and the resultant birth outcomes, early child health and maternal health.

Methods and Design

Fifty-seven schools (86% of 66 eligible secondary schools) in Perth, Australia were recruited to the clustered (by school) randomised trial, with even randomisation to the intervention and control arms. Between 2003 and 2006, the VIP program was administered to 1,267 participants in the intervention schools, while 1,567 participants in the non-intervention schools received standard curriculum. Participants were all female and aged between 13-15 years upon recruitment. Pre and post-intervention questionnaires measured short-term impact and participants are now being followed through their teenage years via data linkage to hospital medical records, abortion clinics and education records. Participants who have a live birth are interviewed by face-to-face interview. Kaplan-Meier survival analysis and proportional hazards regression will test for differences in pregnancy, birth and abortion rates during the teenage years between the study arms.

Discussion

This protocol paper provides a detailed overview of the trial design as well as initial results in the form of participant flow. The authors describe the intervention and its delivery within the natural school setting and discuss the practical issues in the conduct of the trial, including recruitment. The trial is pragmatic and will directly inform those who provide Infant Simulator based programs in school settings.

Trial registration

ISRCTN24952438  相似文献   
8.
Protective immunity against Mycobacterium tuberculosis involves major histocompatibility complex class I (MHC-I)- and CD1-restricted CD8 T cells, but the mechanisms underlying antigen delivery to antigen-presenting molecules remain enigmatic. Macrophages, the primary host cells for mycobacteria, are CD1-negative. Here we show that M. tuberculosis phagosomes are secluded from the cytosolic MHC-I processing pathway and that mycobacteria-infected cells lose their antigen-presenting capacity. We also show that mycobacteria induce apoptosis in macrophages, causing the release of apoptotic vesicles that carry mycobacterial antigens to uninfected antigen-presenting cells (APCs). Inhibition of apoptosis reduced transfer of antigens to bystander cells and activation of CD8 T cells. Uninfected dendritic cells, which engulfed extracellular vesicles, were indispensable for subsequent cross-presentation of antigens, through MHC-I and CD1b, to T cells from mycobacteria-sensitized donors. This new 'detour' pathway for presentation of antigens from a phagosome-contained pathogen shows the functional significance of infection-induced apoptosis in the activation of CD8 T cells specific for both protein and glycolipid antigens in tuberculosis.  相似文献   
9.
The effects of the trichothecene mycotoxins (acetyl T-2 toxin, T-2 toxin, HT-2 toxin, palmityl T-2 toxin, diacetoxyscirpenol (DAS), deoxynivalenol (DON), and T-2 tetraol) on bovine platelet function were examined in homologous plasma stimulated with platelet activating factor (PAF). The mycotoxins inhibited platelet function with the following order of potency: acetyl T-2 toxin > palmityl T-2 toxin = DAS > HT-2 toxin = T-2 toxin. While T-2 tetraol was completely ineffective as an inhibitor, DON exhibited minimal inhibitory activity at concentrations above 10×10?4M. The stability of the platelet aggregates formed was significantly reduced in all mycotoxin treated platelets compared to that of the untreated PAF controls. It is suggested that the increased sensitivity of PAF stimulated bovine platelets to the more lipophilic mycotoxins may be related to their more efficient partitioning into the platelet membrane compared to the more hydrophilic compounds.  相似文献   
10.
Langerhans cells (LC) are a unique subset of dendritic cells (DC), present in the epidermis and serving as the first line of defense against pathogens invading the skin. To investigate the role of human LCs in innate immune responses, we examined TLR expression and function of LC-like DCs derived from CD34+ progenitor cells and compared them to DCs derived from peripheral blood monocytes (monocyte-derived DC; Mo-DC). LC-like DCs and Mo-DCs expressed TLR1-10 mRNAs at comparable levels. Although many of the TLR-induced cytokine patterns were similar between the two cell types, stimulation with the TLR3 agonist poly(I:C) triggered significantly higher amounts of the IFN-inducible chemokines CXCL9 (monokine induced by IFN-gamma) and CXCL11 (IFN-gamma-inducible T cell alpha chemoattractant) in LC-like DCs as compared with Mo-DCs. Supernatants from TLR3-activated LC-like DCs reduced intracellular replication of vesicular stomatitis virus in a type I IFN-dependent manner. Finally, CXCL9 colocalized with LCs in skin biopsy specimens from viral infections. Together, our data suggest that LCs exhibit a direct antiviral activity that is dependent on type I IFN as part of the innate immune system.  相似文献   
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