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BACKGROUND: Endoscopic biliary stenting for pancreaticobiliary malignancy is often limited by recurrent stent occlusion as a result of bacterial biofilm formation and sludge deposition. Bile immunoglobulins are thought to be important in combating biliary sepsis. OBJECTIVES: To investigate whether bile immunoglobulins are involved in the pathogenesis of stent blockage. DESIGN: Immunohistochemical technique was used to study the distribution of bile immunoglobulins, bacteria and sludge in blocked biliary stents. METHODS: Patients with malignant obstructive jaundice were palliated by endoscopic insertion of a 10-FG polyethylene stent into the biliary tract. Blocked stents were retrieved from those who presented with recurrent jaundice and fever. The stents were cross-sectionally cut into slices and fixed in formalin. Immunoglobulins were demonstrated by the peroxidase-anti-peroxidase staining procedure using rabbit anti-serum. RESULTS: The central bulk of the stent deposits appeared as an amorphous, structureless material. IgA was found as a rim of dark brown discoloration at the periphery. IgG showed similar distribution and intensity to that of IgA whereas little IgM was detected. CONCLUSIONS: Bile immunoglobulins may facilitate bacterial adhesion, clumping, and hence biofilm formation on the stent surface.  相似文献   
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The effect of high affinity galanin antagonist M35 on neurogenic cutaneous vasodilatation has been studied in the pigeon using a Laser Doppler Imager. Cutaneous application of mustard oil or antidromic electrical stimulation of a cutaneous nerve produced a small increase in skin blood flow. Close arterial injection of M35 prior to chemical or electrical stimulation resulted in a marked augmentation of the vasodilatory response. This effect was abolished by chronic denervation. The results suggest a nerve-mediated inhibitory effect of endogenous galanin on neurogenic cutaneous vasodilatation in the pigeon skin and provide the first experimental evidence for an inhibitory local regulatory function of cutaneous sensory nerves at least in the avian skin.  相似文献   
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Information Systems and e-Business Management - During the past few years, mashups have gained wide attention as they utilize Web 2.0 technologies in order to combine data, as well as the...  相似文献   
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A copper-nanoparticle-doped carbon was prepared from an alginate based precursor in a one step carbonisation-reduction procedure based on the modified polyol process. The ion exchange capacity of the precursor as well as the porosity, metal content, thermal properties, of the final product, were investigated. The preparation route leads to a porous carbon/copper composite with predefined metal loading reaching up to over 30% (w/w) of finely dispersed Cu nanoparticles of fairly uniform size. NO catalytic abatement evaluation showed high efficiency even at low temperatures compared to other recently reported carbon supported catalysts.  相似文献   
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Alternative splicing has been shown to occur at the metabotropic glutamate receptor 1 (mGluR1) gene. Three main isoforms that differ in their carboxy-termini have been described so far and named mGluR1alpha, mGluR1beta and mGluR1c. These variants when expressed in recombinant systems all activate phospholipase C, although the [Ca2+] signals generated have different kinetics. Tissue distribution studies of specific mGluR1 splice variants are limited to the mGluR1alpha isoform. In the present work, we examined the localization of mGluR1beta in the adult rat and mouse forebrain by using a specific antipeptide antibody. Furthermore, the mGluR1beta immunostaining was compared with that obtained with antibodies specific for mGluR1alpha or with a pan-mGluR1 antibody which recognizes all isoforms. mGluR1beta-like immunoreactivity (LI) was found confined to the neuropil and neuronal perikarya and appeared discretely distributed in the rodent forebrain. Differential cellular distribution between mGluR1alpha and mGluR1beta was observed. In the hippocampus, mGluR1alpha-LI was restricted to non-principal neurons in all fields, whereas mGluR1beta-LI was strongest in principal cells of the CA3 field and dentate granule cells but absent in CA1. We have also shown that the vast majority of neurons in the striatum express mGluR1. The predominant form appeared to be mGluR1beta, with a distribution pattern reflecting the patch-matrix organization of the striatum. The specificity of the immunoreactivity described for mGluR1 splice variants was confirmed in mGluR1-deficient mice. The observation of a different cellular and regional distribution of mGluR1 splice variants, in particular in the hippocampus, suggests that they may mediate different roles in synaptic transmission.  相似文献   
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