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51.
The spectrum of GI strongyloidiasis: an endoscopic-pathologic study   总被引:3,自引:0,他引:3  
BACKGROUND: The aim of this study was a detailed endoscopic-pathologic assessment of patients with various forms of GI strongyloidiasis. METHODS: Six patients with a diagnosis of GI strongyloidiasis who underwent endoscopic evaluation during a 3-year period (January 1998-January 2001) were included. Published information was reviewed in detail, focusing on the endoscopic features and the diagnostic approach to this parasitosis. OBSERVATIONS: Strongyloidiasis has a broad range of endoscopic features. In the duodenum, the findings included edema, brown discoloration of the mucosa, erythematous spots, subepithelial hemorrhages, and megaduodenum. In the colon, the findings included loss of vascular pattern, edema, aphthous ulcers, erosions, serpiginous ulcerations, and xanthoma-like lesions, and, in the stomach, thickened folds and mucosal erosions. A histopathologic diagnosis of strongyloidiasis was made in all cases. CONCLUSIONS: Strongyloidiasis can involve any segment of the GI tract. EGD with procurement of biopsy specimens from the duodenum was the most accurate method of diagnosis in this case series.  相似文献   
52.
The unaffected skin of eighteen patients with dermatitis herpetiformis (D.H.), twenty-two patients with cœliac disease (C.D.), and eight controls were examined using direct immunofluorescence and class-specific fluorescein-conjugated anti-human IgA, IgM, and IgG antisera. All eighteen patients with D.H. showed IgA deposits in the skin: in seventeen the deposits were only found in the dermal papillæ, whilst in one it was found in a continuous line below the basement membrane, confirmed by immuno-electronmicroscopy. IgM deposits were also found in the dermal papillæ in three patients with D.H. and IgG deposits below the basement membrane in one patient. In cœliac disease, however, only one of the twenty-two patients showed papillary IgA deposits and one had continuous IgM deposits. These immunoglobulin deposits in D.H. and C.D. seem to be on the reticulin of the dermal papillæ. It is suggested that in D.H. there is a fault of the reticulin in the skin and small intestine, whilst in cœliac disease it is present in the small intestine but not in the skin. The reticulin cross-reacts with gluten complexes to give rise to an immunological reaction. In support of this hypothesis we have demonstrated cross-reactivity between gluten and reticulin.  相似文献   
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54.
Studies of GB hepatitis agent in tamarins   总被引:4,自引:0,他引:4  
Three tamarins (Saguinus labiatus), two of which had previously been infected with hepatitis A virus and parenteral non-A, non-B hepatitis, were inoculated intravenously with the agent of GB hepatitis. All three animals developed alanine aminotransferase abnormalities 2 weeks after inoculation. Peak alanine aminotransferase levels were recorded 4 weeks postinoculation. These declined thereafter but continued to fluctuate at abnormal levels for 32 weeks. Liver biopsies showed liver cell swelling and inflammation with focal necrosis. Portal tracts and areas around central veins were heavily infiltrated with mononuclear cells. A fourth animal (no previous exposure to hepatitis viruses) inoculated with GB was killed on Day 15 postinoculation. Serum and extracts of liver and feces from this day were used as inocula for three other animals. Only the serum and liver extract transmitted GB hepatitis. The fecal specimen did not transmit and a fecal extract taken at a later date from another animal was also noninfectious. GB hepatitis virus is distinct from the viruses causing Type A and blood-borne non-A, non-B-hepatitis. Although the virus is present in serum and has previously been transmitted per os, it is not shed in feces.  相似文献   
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56.
The emergency department (ED) is an essential component of the public health response plan for control of acute respiratory infectious threats. Effective respiratory hygiene in the ED is imperative to limit the spread of dangerous respiratory pathogens, including influenza, severe acute respiratory syndrome, avian influenza, and bioterrorism agents, particularly given that these agents may not be immediately identifiable. Sustaining effective respiratory control measures is especially challenging in the ED because of patient crowding, inadequate staffing and resources, and ever-increasing numbers of immunocompromised patients. Threat of contagion exists not only for ED patients but also for visitors, health care workers, and inpatient populations. Potential physical sites for respiratory disease transmission extend from out-of-hospital care, to triage, waiting room, ED treatment area, and the hospital at large. This article presents a summary of the most current information available in the literature about respiratory hygiene in the ED, including administrative, patient, and legal issues. Wherever possible, specific recommendations and references to practical information from the Centers for Disease Control and Prevention are provided. The "Administrative Issues" section describes coordination with public health departments, procedures for effective facility planning, and measures for health care worker protection (education, staffing optimization, and vaccination). The patient care section addresses the potentially infected ED patient, including emergency medical services concerns, triage planning, and patient transport. "Legal Issues" discusses the interplay between public safety and patient privacy. Emergency physicians play a critical role in early identification, treatment, and containment of potentially lethal respiratory pathogens. This brief synopsis should help clinicians and administrators understand, develop, and implement appropriate policies and procedures to address respiratory hygiene in the ED.  相似文献   
57.
Conditioned medium (CM) from lectin-stimulated human leukocytes contains factors that induce human promyelocytic cell lines to differentiate along the monocytic pathway. In this report, we show that human promyelocytic cell lines are also induced to differentiate along this pathway by immune interferon (IFN gamma). Various preparations of IFN alpha tested did not induce this differentiation. In cultures containing IFN gamma, the cells are induced to coordinately express monocyte markers and functions such as monocyte-specific surface antigens, HLA-DR antigens, nonspecific esterase, receptors for the Fc fragment of IgG, and the ability to mediate antibody-dependent cell- mediated cytotoxicity. Our data indicate that differentiation induced by IFN gamma is not secondary to an arrest of growth of promyelocytic cell lines, but rather that a proportion of cells is induced along a programmed pathway of terminal differentiation similar to that of normal monocytes. CM contains IFN gamma, but its ability to induce differentiation is greater than expected on the basis of its content of IFN gamma. Treatments at 56 degrees C or at pH 2.0, which abolish IFN gamma activity, abrogate the differentiation ability of CM. The antiviral activity and the differentiation activity contained in the CM are coeluted from gel filtration and reverse-phase columns. Monoclonal antibodies anti-IFN gamma, which completely abrogate the differentiation ability of IFN gamma and the antiviral activity in the CM, completely suppress the induction of some monocyte markers by CM, but only reduce the expression of others. When IFN gamma is added to CM, promyelocytic cell lines are induced to differentiate to a much greater extent than that induced by either IFN gamma or IFN gamma- depleted CM alone. These results show that the differentiation activity of leukocyte CM is due to the synergistic effect of IFN gamma and other factors not yet identified.  相似文献   
58.
Contractile activation of detrusor smooth muscle is initiated by the release of transmitters from motor nerves. Acetylcholine is a ubiquitous transmitter, as also is adenosine triphosphate (ATP) in many animal bladders and in people from several patient groups with pathological bladder function. In recent years there has been progress in explaining several cellular mechanisms that link transmitter release to contraction and these will be considered. The lifetime of ATP in the neuromuscular junction is finite and broken down ultimately to adenosine, which can exert modulatory control of contractile activation. Adenosine depresses nerve-mediated contractions and two sites of action have been proposed: an action on the motor nerves via A receptors to depress further transmitter release and a less well-defined depressant effect on the detrusor muscle. The Ca2+ ions that activate the contractile proteins are derived from intracellular stores, which releases their content via IP receptor activation and Ca2+-induced Ca2+ release. Filling of the stores in the rest interval is mediated via transmembrane flux of Ca2+through Ca2+ channels. Activation of the channels is regulated by the level of the intracellular [Ca2+], via activation and inactivation of Ca2+-sensitive K channels. Thus, Ca2+ store filling is regulated by intracellular [Ca2+] via a negative feedback process. The presence and physiological function of spontaneous contractions in detrusor remain contentious and little is known about their origin. One possibility is that they originate from random Ca2+ sparks, i.e. localized transient increases of [Ca2+] that may eventually progress to generate a cellular Ca2+ transient. Observations by confocal microscopy have revealed the presence of such sparks, especially near the cell membrane, and thus provide a cellular basis for spontaneous contractions. Finally, the questions arises as to whether detrusor smooth muscle is a functional syncitium. The demonstration of small gap junctions by electron microscopy and the demonstration of the gap junction protein connexin45 indicate that the muscle mass may indeed be functionally connected. The implications regarding the spread of excitation are discussed.  相似文献   
59.
The study was designed to assess the influences of antiarrhythmic therapy on exercise tolerance in patients with coronary artery disease and ventricular arrhythmias. Subjects for this study were subdivided into 3 groups: group I - 46 patients treated with amiodarone 1,200 mg daily during 10 days and 200-600 mg daily within next days, group II - 79 patients receiving disopyramide 300-600 mg daily, group III - 129 patients with combined administration of disopyramide 300-600 mg daily and propranolol 30-240 mg daily. propranolol 30-240 mg daily. Submaximal exercise stress testing was performed in each patient before treatment and after the medication for 4 weeks (group I) and for 2 weeks (groups II, III). The following parameters have been evaluated: maximal archived workload, maximal heart rate blood pressure response, double product (maximal heart rate x maximal systolic blood pressure), reasons for ending the test (target heart rate, typical angina, exhaustion, ST-segment depression greater than or equal to 2 mm, occurrence of ventricular arrhythmia, blood pressure greater than 250/120 mm Hg, significant drop in systolic pressure). Positive result of exercise ECG was defined: horizontal or down-sloping ST-segment depression greater than or equal to 1 mm and/or typical chest pain. The data from the first and second tests were estimated for significance of differences between the mean values with following results: 1) maximal achieved workload, 86 +/- 46 and 103 +/- 49 W (p less than 0.02) in group I; 101 +/- 64 and 106 +/- 50 W (NS) in group II; 107 +/- 55 and 119 +/- 54 W, W (p less than 0.01) in group III.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
60.
Recurrence of volvulus after sigmoidectomy   总被引:1,自引:3,他引:1  
Summary Three patients had recurrences of left-sided colonic volvulus after allegedly total resections of redundant sigmoid loops. All three patients had chronic, acquired megacolon. Other instances of late recurrence of volvulus after sigmoidectomy are documented in the literature. Sigmoidectomy may be an inadequate operation for sigmoid volvulus in younger patients and/or in patients with severe chronic megacolon. The decision to perform an interval operation and the selection of the type of operation must take this into account.  相似文献   
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