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41.
The distribution of adrenergic nerves to the microcirculation of the wing web of the bat was studied in whole-mount preparations employing glyoxylic acid fluorescence histochemistry. A dense perivascular adrenergic nerve plexus consisting of various-sized nerve bundles surrounded the arteries. The accompanying veins were sparsely innervated by small nerve bundles or single axons. Arterioles also possessed a dense perivascular plexus comprised of a loose network of small axon bundles. Muscular venules accompanying most arterioles were supplied by a small number of varicose axons which surrounded these vessels in a loose network. The majority of the terminal arterioles were devoid of any direct innervation. The proximal segment of some terminal arterioles was innervated by one or two axons which were observed to diverge from the vessels and terminate in the tissue. The true capillaries, postcapillary venules, and lymphatics possessed no direct adrenergic innervation. Surgical sectioning of the appropriate nerve trunks or administration of 6-hydroxydopamine caused complete disappearance of all fluorescent adrenergic axons in the wing web. Faint acetylcholinesterase-positive staining was observed in a perivascular plexus surrounding the arteries and arterioles. A much diminished acetylcholinesterase activity was observed after treatment with 6-hydroxydopamine which implies that this enzymatic activity resides in the adrenergic nerves.  相似文献   
42.
The purpose of this paper is to describe the intraoperative management of a type IIIb endoleak after deployment of a bifurcated endograft in a patient with narrow iliac access vessels. A 62-year-old man underwent elective endovascular repair (EVAR) of a 53 mm abdominal aortic aneurysm. After device deployment, a large IIIb endoleak, arising from the main body of the device, was visualized. Narrow iliac vessels precluded deployment of a second bifurcated graft, and the endoleak was successfully excluded with an aortomonoiliac device, followed by contralateral iliac occlusion and subsequent creation of a femorofemoral bypass. At 1-year follow-up, the aneurysm remains excluded and is decreasing in size. Type III endoleaks are a known complication of EVAR, requiring immediate treatment through their association with aneurysm enlargement and rupture. If an additional bifurcated graft cannot be used, aortomonoiliac conversion represents a feasible endovascular alternative treatment for type III endoleaks, other than conversion to open surgical repair. Therefore, aortomonoiliac converters with appropriate occluder devices should be readily available during deployment of bifurcated devices.  相似文献   
43.
The purpose of this study was to examine whether variability in the shape of dendritic spines affects protein movement within the plasma membrane. Using a combination of confocal microscopy and the fluorescence loss in photobleaching technique in living hippocampal CA1 pyramidal neurons expressing membrane-linked GFP, we observed a clear correlation between spine shape parameters and the diffusion and compartmentalization of membrane-associated proteins. The kinetics of membrane-linked GFP exchange between the dendritic shaft and the spine head compartment were slower in dendritic spines with long necks and/or large heads than in those with short necks and/or small heads. Furthermore, when the spine area was reduced by eliciting epileptiform activity, the kinetics of protein exchange between the spine compartments exhibited a concomitant decrease. As synaptic plasticity is considered to involve the dynamic flux by lateral diffusion of membrane-bound proteins into and out of the synapse, our data suggest that spine shape represents an important parameter in the susceptibility of synapses to undergo plastic change.  相似文献   
44.
Mouse monoclonal antibodies B1 and B3 are specific for natural and Escherichia coli-derived recombinant human gamma-interferon (IFN-gamma). The two antibodies recognize different epitopes of the IFN-gamma molecule and do not compete with each other's binding. We have used these two antibodies to construct a solid-phase, sandwich immunoradiometric assay for human IFN-gamma. Purified antibody B1 was coated on polystyrene beads (0.64 cm in diameter) and used as the solid-phase immunoadsorbent and antibody B3 was labeled with 125I and used as tracer. This assay can be completed in about 4 hr and is capable of detecting IFN-gamma levels in human serum or tissue culture fluids as low as 0.1 NIH reference unit/ml. Recombinant human IFN-gamma derived from E. coli was detectable at a concentration of 0.02 ng/ml. The assay appears to be specific for the biologically active forms of IFN-gamma, since after exposure to pH 2, 37 degrees C, or 56 degrees C, biological activity and reactivity in the immunoradiometric assay decreased in parallel. The immunoradiometric assay can be employed for the analysis of the structural characteristics of the human IFN-gamma molecule.  相似文献   
45.
By the end of May 2000, 54 definite cases and 13 probable cases of vCJD had been notified in the United Kingdom by the National CJD Surveillance Unit set up in 1990. All definite cases for whom data are available are methionine homozygous at codon 129 of  相似文献   
46.
Fatal swine influenza pneumonia during late pregnancy   总被引:1,自引:0,他引:1  
Serious morbidity or death from swine influenza infection is unusual in the immunocompetent host. We present a fatal case of pneumonia caused by this virus in a previously healthy 32-year-old woman during her third trimester of pregnancy, and review all published case reports of swine influenza in United States civilians. Pregnancy may be a predisposing factor to fulminant infection with swine influenza virus.  相似文献   
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