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1.
A neuroendocrine carcinoma of the thymus with an ectopic adrenocorticotropic hormone (ACTH) syndrome and melanocytic differentiation is described. ACTH, neuron-specific enolase (NSE) and S-100 protein were identified in the tumor by immunocytochemistry. Neurosecretory granules and melanosomes could be demonstrated in different cell populations by electronmicroscopy. The clinicopathologic findings are presented. The literature is briefly discussed. 相似文献
2.
Intestinal schistosomiasis japonica: CT-pathologic correlation 总被引:1,自引:0,他引:1
Lee RC; Chiang JH; Chou YH; Rubesin SE; Wu HP; Jeng WC; Hsu CC; Tiu CM; Chang T 《Radiology》1994,193(2):539
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The patellofemoral joint was imaged with magnetic resonance (MR) in the axial plane while the knee was positioned from 0 degrees to 32 degrees of flexion (nine positions). These multiple sequential images obtained within the early phases of flexion of the knee were viewed in a "cine-loop" format, producing a kinematic study that clearly demonstrated the relationship of the patella to the trochlear groove. Four healthy subjects and one patient with known bilateral subluxing patellae were studied. The preliminary results suggest that kinematic MR imaging of the patellofemoral joint is potentially useful for the evaluation of patellar tracking abnormalities. 相似文献
6.
Identification of Borrelia burgdorferi and B. hermsii using DNA hybridization probes. 总被引:4,自引:9,他引:4
T G Schwan W J Simpson M E Schrumpf R H Karstens 《Journal of clinical microbiology》1989,27(8):1734-1738
Fragments of plasmid DNA from Borrelia burgdorferi and B. hermsii were cloned and tested for specificity as hybridization probes to identify these two species of pathogenic spirochetes. Three fragments from the 49-kilobase-pair linear plasmid of B. burgdorferi were tested: a 500-base-pair (bp) HindIII fragment (probe 49A), a 445-bp PstI-HindIII fragment (probe 3G), and a 320-bp HindIII fragment (probe 16H). When hybridized to purified DNA or whole spirochetes, all of the probes distinguished B. burgdorferi from the other species examined, including B. hermsii, B. parkeri, B. turicatae, B. coriaceae, B. crocidurae, and B. anserina. Probe 49A was the most useful, however, hybridizing with all strains of B. burgdorferi originating from both North America and Europe while not cross-hybridizing with B. hermsii. A 790-bp HindIII fragment of B. hermsii DNA hybridized with DNA and whole spirochetes of this species and also with B. parkeri, confirming the close relatedness of these two species. These probes provide a new method of identifying these Borrelia species once the organisms have been grown in culture. 相似文献
7.
Antibody to a 39-kilodalton Borrelia burgdorferi antigen (P39) as a marker for infection in experimentally and naturally inoculated animals. 总被引:11,自引:8,他引:11 下载免费PDF全文
W J Simpson W Burgdorfer M E Schrumpf R H Karstens T G Schwan 《Journal of clinical microbiology》1991,29(2):236-243
Borrelia burgdorferi expresses a conserved, species-specific 39-kDa protein (P39) that can stimulate antibodies during human infection. To confirm that anti-P39 antibodies are produced consistently in animals exposed to infectious spirochetes, white-footed mice, Peromyscus leucopus, and laboratory white mice, Mus musculus (strain BALB/c), were experimentally inoculated with either infectious or noninfectious B. burgdorferi and the antibody response to P39 was determined by immunoblot at 21 days postinoculation. All mice inoculated with approximately 10(7) infectious B. burgdorferi produced anti-P39 antibodies and were cultured positive for this spirochete. Mice inoculated with similar numbers of inactivated or viable noninfectious B. burgdorferi still producing P39 did not induce anti-P39 antibodies. By contrast, putative antiflagellin antibodies were detected in less than 18% of the infected animals, which supports the notion that antibody reactive with flagellin may not be reliable as a marker for B. burgdorferi exposure as was originally thought. Mice infected with B. burgdorferi following exposure to ticks (Ixodes dammini) produced anti-P39 antibodies no later than 7 days postinfection, indicating that P39 is an effective immunogen in natural infections. Notably, anti-P39 antibodies were the predominant B. burgdorferi reactive antibodies detected early in the infection. Our results indicate that anti-P39 antibodies are produced in response to an active infection and are therefore reliable markers for infection in experimentally and naturally inoculated animals. 相似文献
8.
In heat-treated polyamide 6 and polyamide 6,6 fibres UV/VIS-active chromophores are found, which originate from two different sources: one type of chromophore (structured UV spectrum) arises during polycondensation and the spinning of the fibres (molten phase), the other (nonstructured UV spectrum) occurs as a result of a thermo-oxidation is based on conjugated oligoenimies , as is shown by a combination of UV/VIS spectroscopy and fluorescence excitation and emission spectroscopy with chemical analysis. The concentration of the various oligoenimine species depends upon the temperature and duration of the thermooxidation. For a temperature of 160°C and a duration of 2 hours, for example, the following oligoenimine concentrations were found (UV spectroscopy with computer-aided evaluation): for i = 0: 44; i = 1: 13; i = 2: 4; i = 3: 1; i = 4: 0,3 (values expressed in mmol/kg). 相似文献
9.
Marrow regeneration after mechanical depletion 总被引:1,自引:0,他引:1
The origin of marrow regeneration after mechanical depletion was reinvestigated in mouse chimeras. The results were compatible with the local origin of stem cells from remnants of incompletely removed marrow, but not with their origin from a common precursor of both bone and hemopoietic cell lines. In transplanted femurs depleted by a modified technique of in vivo evacuation of marrow, hemopoietic regeneration failed to occur. The presence of hemopoietic stem cells in the Haversian canals was thus excluded. The demonstration of ample hemopoiesis with minimal bone formation in nondepleted controls in which bone marrow initially became necrotic provided new evidence that osteogenesis was not a prerequisite of hemopoietic regeneration. 相似文献
10.
A 15 year old boy with autoimmune polyendocrinopathy-candidosis-ectodermal dystrophy syndrome suffered recurrent episodes of severe intractable diarrhoea, steatorrhoea, and hypocalcaemia. The only treatment modality, which controlled the malabsorption syndrome, was immunosuppression with intravenous high dose methylprednisolone and oral methotrexate maintenance therapy. 相似文献