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排序方式: 共有932条查询结果,搜索用时 15 毫秒
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GP SCHWAB AL BLUM E BODNER B DALLEMAGNE K GLASER H KOOP F PACE W RÖSCH JR SIEWERT G WETSCHER 《Journal of gastroenterology and hepatology》1997,12(12):785-789
Gastroesophageal reflux disease (GERD) is the most common disease of the upper gastrointestinal tract. With the introduction of proton pump inhibitors medical treatment of GERD has been significantly improved. However, the development of laparoscopic antireflux surgery resulted in an increasing interest of surgeons in this disease. An interactive meeting was organized in order to develop an agreement between gastoenterologists and surgeons regarding therapeutic decisions and this is the main topic of this paper. 相似文献
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Edward?J?HolloxEmail author Jane?Davies Uta?Griesenbach Juliana?Burgess Eric?WFW?Alton John?AL?Armour 《Journal of negative results in biomedicine》2005,4(1):9
Human beta-defensin 2 (DEFB4, also known as DEFB2 or hBD-2) is a salt-sensitive antimicrobial protein that is expressed in
lung epithelia. Previous work has shown that it is encoded in a cluster of beta-defensin genes at 8p23.1, which varies in
copy number between 2 and 12 in different individuals. We determined the copy number of this locus in 355 patients with cystic
fibrosis (CF), and tested for correlation between beta-defensin cluster genomic copy number and lung disease associated with
CF. No significant association was found. 相似文献
6.
Analysis of the tissue distribution of the rat C5a receptor and inhibition of C5a-mediated effects through the use of two MoAbs 总被引:2,自引:0,他引:2
The C5-anaphylatoxin C5a is a protein of 74 (human) or 77 (rat) amino-acid residues, respectively, the generation of which may be induced by either the classical and/or the alternative pathways. C5a binds specifically to its receptor (C5aR/CD88) which belongs to the superfamily of G-protein-coupled receptors with seven transmembrane segments. In this study we describe the tissue distribution of the rat C5aR (rC5aR) and the blocking of its ligand by the application of two monoclonal antibodies (MoAbs). The first antibody (MoAb R63) which is directed against the amino-terminal domain Ex1 of the rat C5aR was generated in mice immunized with RBL-2H3 cells which had been stably transfected with the rat C5a receptor gene. Checking the rC5aR expression in various tissues bronchial epithelial cells stained positive only in tissue samples from animals with a mycoplasm infection indicating that the receptor may be induced in this cell type as a consequence of an inflammatory process. Using immunohistochemistry there was no evidence for nonmyeloid expression in the large or small intestine, heart, lung, kidney or liver of the normal rat. The MoAb R63 was found to be a reliable tool for the investigation of the expression of the receptor by FACS analyses or immunohistochemistry. Despite numerous attempts neutralizing antibodies could not be generated against the receptor. Therefore a C5a-ligand neutralizing MoAb was generated against the synthesized carboxyterminal 20mer peptide. This antibody (6-9F) recognized the carboxy terminus of C5a/C5a-FLUOS and prevented its binding at a three-fold molar excess as evidenced by FACS-analyses. It also blocked the C5a-mediated signal transduction as demonstrated by the inhibition of intracellular Ca2+-release (at a 16-fold molar excess) and the release of N-Acetyl-beta-D-glucosaminidase (at a 25-fold molar excess). 相似文献
7.
Missense FGFR3 mutations create cysteine residues in thanatophoric dwarfism type I (TD1) 总被引:10,自引:1,他引:10
Rousseau F; el Ghouzzi V; Delezoide AL; Legeai-Mallet L; Le Merrer M; Munnich A; Bonaventure J 《Human molecular genetics》1996,5(4):509-512
Thanatophoric dwarfism (TD) is a sporadic lethal skeletal dysplasia with
micromelic shortening of the limbs, macrocephaly, platyspondyly and reduced
thoracic cavity. In the most common subtype (TD1), femurs are curved, while
in TD2, straight femurs are associated with cloverleaf skull. Mutations in
the fibroblast growth factor receptor 3 (FGFR3) gene were identified in
both subtypes. While TD2 was accounted for by a single recurrent mutation
in the tyrosine kinase 2 domain, TD1 resulted from either stop codon
mutations or missense mutations in the extracellular domain of the gene.
Here, we report the identification of FGFR3 mutations in 25/26 TD cases.
Two novel missense mutations (Y373C and G370C) were detected in 8/26 and
1/26 TD1 cases respectively. Both mutations created cysteine residues in
the juxta extramembrane domain of the receptor. Sixteen cases carried the
previously reported R248C (9/26 cases), S249C (2/26 cases) or stop codon
FGFR3 mutations (5/26 cases). Our results suggest that TD1 is a genetically
homogeneous condition and give additional support to the view that newly
created cysteine residues in the extracellular domain of the protein play a
key role in the severity of the disease.
相似文献
8.
Role of tryptophan degradation in respiratory burst-independent antimicrobial activity of gamma interferon-stimulated human macrophages. 总被引:8,自引:13,他引:8
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H W Murray A Szuro-Sudol D Wellner M J Oca A M Granger D M Libby C D Rothermel B Y Rubin 《Infection and immunity》1989,57(3):845-849
To determine whether extracellular tryptophan degradation represents an oxygen-independent antimicrobial mechanism, we examined the effect of exogenous tryptophan on the intracellular antimicrobial activity of gamma interferon (IFN-gamma)-stimulated human macrophages. IFN-gamma readily induced normal monocyte-derived macrophages (MDM) to express indoleamine 2,3-dioxygenase (IDO) activity and stimulated MDM, alveolar macrophages, and oxidatively deficient chronic granulomatous disease MDM to degrade tryptophan. All IFN-gamma-activated, tryptophan-degrading macrophages killed or inhibited Toxoplasma gondii, Chlamydia psittaci, and Leishmania donovani. Although exogenous tryptophan partially reversed this activity, the increases in intracellular replication were variable for normal MDM (T. gondii [5-fold], C. psittaci [3-fold], L. donovani [2-fold]), chronic granulomatous disease MDM (T. gondii [2.5-fold], C. psittaci [5-fold]), and alveolar macrophages (T. gondii [1.5-fold], C. psittaci [1.5-fold]). In addition, IFN-alpha and IFN-beta also stimulated normal MDM to express IDO and degrade tryptophan but failed to induce antimicrobial activity, and IFN-gamma-treated mouse macrophages showed neither IDO activity nor tryptophan degradation but killed T. gondii and L. donovani. These results suggest that while tryptophan depletion contributes to the oxygen-independent antimicrobial effects of the activated human macrophage, in certain cytokine-stimulated cells, tryptophan degradation may be neither sufficient nor required for antimicrobial activity. 相似文献
9.
Morphological analysis of degeneration and regeneration of syncytiotrophoblast in first trimester placental villi during organ culture 总被引:3,自引:1,他引:3
We have recently shown using dansyl-L-lysine exclusion studies that the
release of human chorionic gonadotrophin (HCG) in conjunction with L-
lactate dehydrogenase (LDH) from first trimester villi during organ culture
is symptomatic of syncytiotrophoblast degeneration. The purpose of this
study was to examine chorionic villi at the ultrastructural level in order
to determine events occurring during organ culture. The tissue was sampled
after 0, 24, 48 and 120 h in culture and processed for electron microscopy.
In addition to confirming the previously recorded syncytial degeneration,
the electron micrographs showed clearly the generation of a new
syncytiotrophoblast layer. The new layer, derived from differentiating
cytotrophoblast cells, was largely formed by 48 h and was maintained for at
least 120 h in culture. This study demonstrates a model which provides an
opportunity to study the differentiation of cytotrophoblast cells whilst
they retain their anatomical relationships within the villous structure.
相似文献
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