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Post cardiac injury syndrome (PCIS) is known to occur following myocardial infarction, cardiac surgery, blunt chest trauma, percutaneous left ventricular puncture and pace-maker implantation. The diagnosis is one of exclusion. We report a case of PCIS following cardiac surgery who showed false positive IgG, IgM antibodies to antigen A60 of Mycobacterium tuberculosis in pleural fluid.  相似文献   
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Fine-needle aspiration (FNA) cytology of three cases of Langerhans' cell histiocytosis (eosinophilic granuloma [EG]) of bone in children (mean age--8.3 yr; range 5-11 yr) is presented. Two patients presented with vertebral lesions and the third had a femoral mass. Cytomorphologic features of EG were seen in all cases including Langerhans' cell histiocytes having oval to reniform shape nuclei with nuclear grooving and abundant pale cytoplasm. The background showed a polymorphic population of cells including neutrophils, lymphocytes, foamy histiocytes, and osteoclasts. Moderate numbers of eosinophils were seen in two cases, while eosinophils were sparse in the third case. Ancillary immunocytochemical (ICC) studies performed on the aspirated material demonstrated positive staining for S-100 protein (all three cases) and T-6 antigen (one case). Ultrastructural examination (EM) performed in one case demonstrated characteristic Birbeck granules in the histiocytes. A specific cytologic diagnosis was made in all cases, enabling proper chemotherapy in one case, surgical excision in another and spontaneous resolution in the third case. Our experience demonstrates that FNA cytology can make a definitive diagnosis of EG, especially when coupled with ancillary studies such as ICC and EM on the aspirated material.  相似文献   
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We evaluated the diagnostic contribution of adjunct studies performed on aspirated material in the work-up of pediatric fine-needle aspiration (FNA) biopsies. Ancillary studies were performed on 54 of 136 (39.7%) pediatric FNA biopsies during a 5-year period. In 23 (16.9%) cases, immunocytochemical (ICC) studies, consisting of immunoperoxidase staining of direct smears and/or cell blocks or flow cytometric immunophenotyping, were performed. The studies were adequate in 14 cases (60.9%), suboptimal in five cases (21.7%), and inadequate in four cases (17.4%). Of the adequate and suboptimal cases, the ICC data helped to narrow the differential diagnosis or classify the disease process in eight cases (42.1%), confirmed cytologic impression in nine cases (47.4%), and gave contradictory results in two cases (10.5%). Adequate material for electron microscopy (EM) was obtained in 14/19 cases (73.7%). Ultrastructural studies were diagnostic, or helped classify the disease process in five cases (35.7%), confirmed the cytologic impression in four cases (28.6%), helped exclude diagnostic considerations in three cases (21.4%), and were judged to be non-contributory in two cases (14.3%). Cytogenetic studies revealed six of seven cases (all neoplasms) to have abnormal karyotypes. Special stains for organisms performed on smears from 25 cases including Ziehl-Neelsen, Gomori methenamine silver (GMS), Gram, and Warthin-Starry (WS) were negative except for 1/16 GMS and 4/9 Gram stains. In summary, we found that with appropriate case selection, ancillary studies performed on aspirated material can provide useful information in pediatric FNA cytology.  相似文献   
66.
The antenatal variant of Bartter's syndrome is an autosomal recessive kidney disease characterized by polyhydramnios, premature delivery, hypokalemic alkalosis and hypercalciuria. It is genetically heterogeneous, having been linked recently to mutations in an ATP- sensitive, renal outer medullary K+channel, ROMK, and earlier to mutations in the Na-K-2Cl co-transporter, NKCC2. We characterized four of the mutations reported in three heterozygous ROMK variants of antenatal Bartter's and found that each expressed a distinct phenotype in Sf9 cells. One mutation expressed normal function and appears to be an allelic polymorphism. The other three mutations produced channels with significantly reduced K+fluxes. However, the mechanisms in each case were different and reflected abnormalities in phosphorylation, proteolytic processing or protein trafficking. The different mechanisms may be important in the design of appropriate therapy for patients with this disease.   相似文献   
67.
Prenatal cytogenetic analysis of 71 fetuses conceived by intracytoplasmic sperm injection (ICSI) resulted in the detection of nine (12.7%) chromosome aberrations including two cases of 47,XXY, four cases involving a 45,X cell line and three autosomal trisomies. Molecular analysis of the parental origin of the deleted or supernumerary chromosome was performed by using polymorphic microsatellite markers. Six cases involving a sex chromosome abnormality were found to be of paternal origin while the two trisomic cases that could be analysed were of maternal origin. Two cases involved the same infertile couple who had two consecutive ICSI pregnancies terminated because of a chromosome abnormality. The replaced embryos in both cases originated from a single batch of ICSI fertilized oocytes of which part was used to initiate the first pregnancy and part was cryopreserved and used to initiate the second pregnancy.   相似文献   
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Joshi S  Pleij CW  Haenni AL  Chapeville F  Bosch L 《Virology》1983,127(1):100-111
The existence of subgenomic RNAs is well established in the case of plant viruses such as tobacco mosaic virus (TMV). However, except for the subgenomic coat protein mRNA, it is not known whether the other subgenomic RNAs have a function in the life cycle of the virus. In search of more information about one of the major subgenomic RNAs-intermediate length RNA-2 or I2 RNA-of TMV, in vitro and in vivo translational studies were performed. The I2 RNA, which codes in vitro for the synthesis of a 30K (K = kilodalton) protein, appears to be uncapped as judged by the need of different in vitro translation conditions for the synthesis of this protein, compared to the conditions required for the synthesis of the 126K and 183K proteins coded by the capped genomic RNA. In vivo a protein migrating in the same position as the 30K protein synthesized in vitro can be detected in infected tobacco leaves. Since this protein occurs transiently early upon infection, whether it is virus-coded or virus-induced, it could have an early function during infection.  相似文献   
70.
The aims of this work were to measure the accuracy of one continuous speech recognition product and dependence on the speaker's gender and status as a native or nonnative English speaker, and evaluate the product's potential for routine use in transcribing radiology reports. IBM MedSpeak/Radiology software, version 1.1 was evaluated by 6 speakers. Two were nonnative English speakers, and 3 were men. Each speaker dictated a set of 12 reports. The reports included neurologic and body imaging examinations performed with 6 different modalities. The dictated and original report texts were compared, and error rates for overall, significant, and subtle significant errors were computed. Error rate dependence on modality, native English speaker status, and gender were evaluated by performing ttests. The overall error rate was 10.3 +/- 3.3%. No difference in accuracy between men and women was found; however, significant differences were seen for overall and significant errors when comparing native and nonnative English speakers (P = .009 and P = .008, respectively). The speech recognition software is approximately 90% accurate, and while practical implementation issues (rather than accuracy) currently limit routine use of this product throughout a radiology practice, application in niche areas such as the emergency room currently is being pursued. This methodology provides a convenient way to compare the initial accuracy of different speech recognition products, and changes in accuracy over time, in a detailed and sensitive manner.  相似文献   
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