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61.
Both ultrasonography (US) and cholescintigraphy are used to study gallbladder dynamics. The present study was undertaken to determine whether the two methods provide the same or different information relating to gallbladder emptying. Emptying was simultaneously studied with both methods during infusion of graded physiologic doses of cholecystokinin (CCK) in six healthy subjects. Infusion of stepwise increasing doses of CCK, ranging from 0.03 to 0.5 Ivy dog units per kilogram of body weight per hour (IDU/kg.h), induced significant dose-related increases in plasma CCK, decreases in gallbladder volume assessed with US, and gallbladder emptying assessed with cholescintigraphy. The threshold dose for inducing significant gallbladder emptying was 0.13 IDU/kg.h, as determined with both techniques, indicating similar detection limits. There was a highly significant correlation between decreases in gallbladder volume and decreases in radioactive counts over the gallbladder region, with a tendency toward greater gallbladder responses at sonography during the early phase of gallbladder contraction and toward greater responses at cholescintigraphy during the later phase of gallbladder contraction. It is concluded that these methods can be used interchangeably for the quantitation of gallbladder emptying.  相似文献   
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Until alternate diagnostic methods are discovered, the staging procedure seems to be the most reliable method to establish the presence or absence of abdominal involvement in Hodgkin's disease. Our experience with staging laparotomy in 22 children raises serious questions as to both the risk of operation and the prognostic value of a negative abdominal exploration. Routine use of the staging laparotomy may not be justified in clinical Stage IA patients with lymphocyte-predominant cell type. Because of the hazards and limitations of the staging procedure, vigorous attempts would seem to be indicated to identify subcategories of patients in whom the likelihood of intraabdominal involvement is so small as to negate the value of surgical staging.  相似文献   
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For many years only two human monoclonal antibodies (HMAbs) recognizing the CD4 induced (CD4i) epitopes of HIV-1 gp120 existed. Although a number of new CD4i HMAbs have been published recently, we have noted that in most attempts to produce HMAbs using EBV transformation a majority of antibodies produced in culture are lost within a few weeks. To determine what kinds of antibodies are made in these cultures we devised a semiquantitative culture to assess the frequency of B cells capable of producing antibodies and a microcompetition assay to determine what kinds of antibodies were made. Our results show that in three patients started on HAART during acute infection the most frequently produced antibodies binding to gp120 were directed against the CD4i epitopes. Our observations suggest that CD4i epitopes are much more immunogenic than had been previously appreciated. It is possible that envelope glycoproteins shed from virions and perhaps complexed with CD4 are responsible for eliciting these antibodies. The preservation of well regulated immune responses in these patients, together with repeated exposure to viral antigens (i.e. env), may explain the presence of larger than usual numbers of env-specific B cells that could be detected in EBV transformed cultures.  相似文献   
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Because of their evolving nature and inherent scientific uncertainties, outbreaks of emerging infectious diseases can be associated with considerable fear in the general public or in specific communities, especially when illness and deaths are substantial. Mitigating fear and discrimination directed toward persons infected with, and affected by, infectious disease can be important in controlling transmission. Persons who are feared and stigmatized may delay seeking care and remain in the community undetected. This article outlines efforts to rapidly assess, monitor, and address fears associated with the 2003 severe acute respiratory syndrome (SARS) epidemic in the United States. Although fear, stigmatization, and discrimination were not widespread in the general public, Asian-American communities were particularly affected.  相似文献   
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Frontotemporal lobar degeneration and ubiquitin immunohistochemistry   总被引:6,自引:0,他引:6  
We set out to determine the frequency of the different pathologies underlying frontotemporal degeneration (FTD) in our brain bank series, by reviewing all cases of pathologically diagnosed FTD over the last 12 years. We identified and reviewed 29 cases of FTD and classified them using the most recent consensus criteria with further histological analysis of 6 initially unclassifiable cases. Detailed histological analysis of these 6 cases revealed variable numbers of ubiquitin-positive (tau and alpha-synuclein-negative) inclusions in 5 cases, consistent with the diagnosis of frontotemporal lobar degeneration with ubiquitin-only-immunoreactive neuronal changes (FTLD-U). As a consequence of the current re-evaluation, 18 (62%) of the 29 cases with FTD have underlying pathology consistent with FTLD-U. Therefore in our brain bank series of frontotemporal degeneration, most cases were non-tauopathies with FTLD-U accounting for 62% of all the diagnoses.  相似文献   
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Basset C  Holton J  O'Mahony R  Roitt I 《Vaccine》2003,21(Z2):S12-S23
The skin and contiguous mucosal surfaces define the primary locus of interaction between host and micro-organisms. In this review, we focus on the innate immune system in the mucosa, which manages to deal with invading pathogens, the mechanisms that organisms have evolved in order to circumvent this primary defensive barrier and, finally, potential therapeutic manipulation of the innate immune system that was the focus of meeting at a Euroconference/Workshop on "Novel Strategies of Mucosal Immunisation through Exploitation of Mechanisms of Innate Immunity in Pathogen-Host Interaction", which was held in Siena, Italy, November 2002.  相似文献   
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