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1.
Croup is an acute infectious illness usually occurring in children; it is characterized by brassy cough and stridor. The main pathogens include mainly parainfluenza and influenza viruses. Recently there have been reports of prolonged croup caused by the herpes simplex viruses. We report two cases of prolonged croup due to herpes simplex types 1 and 2. We also review and summarize the reported pediatric cases of herpetic croup.  相似文献   
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This review correlates the imaging findings and histological appearances seen in chordomas in a series of patients presenting at our institution, together with a published literature review. A parallel presentation of photographs of imaging findings and microscopic histological findings is made, with the aim being to enhance recognition of this uncommon but clinically significant entity.  相似文献   
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The tetrapeptide Acetyl-N-Ser-Asp-Lys-Pro (AcSDKP, Seraspenide; Ipsen- Biotech, Paris, France), an inhibitor of murine spleen colony-forming units reduces the number and the percentage in DNA synthesis of progenitors from human unfractionated bone marrow. To determine whether AcSDKP may directly affect the growth potential of purified progenitors even at the most primitive level, CD34+HLA-DRhigh and CD34++HLA-DRlow cells were highly purified by cell sorting. Then, CD34+ subsets were stimulated in liquid culture with combinations of growth factors (GFs) and AcSDKP was added for 20 hours or 6 days and cells plated in methylcellulose. After a 20-hour incubation, we show that AcSDKP (at 10(-10) mol/L) significantly inhibits the colony formation of both CD34+ subsets. Moreover, when added daily for 6 days, AcSDKP: (1) reduces the proliferation of both CD34+ cell fractions stimulated by 3 or 7 GFs, and (2) decreases the number of progenitors generated from the CD34+HLA-DRhigh and CD34++HLA-DRlow cell fractions. Furthermore, we show for the first time, using both high proliferative potential cell and long-term culture initiating cell assays, that AcSDKP inhibits the most primitive cells contained in the CD34++HLA-DRlow subpopulation. Finally, by using limiting dilution assays we demonstrated that AcSDKP acts directly at a single cell level and that its inhibitory effect is reversible and dose dependent.  相似文献   
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We present an unusual case of haematogenous osteomyelitis in the diaphysis of the tibia of an adult leading to a subacute presentation with an extracortical abscess. Fluid from the abscess grew methicillin resistant Staphylococcus aureus (MRSA) on culture; MRSA with the same antibiogram had been grown from the patient’s blood seven years earlier following a bowel resection. Drainage of the abscess and curettage of the bone lesion together with appropriate antibiotic therapy led to resolution of the osteomyelitis.  相似文献   
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The detection and quantitation of apoptotic cells is becoming increasingly important in the investigation of the role of apoptosis in cellular proliferation and differentiation. The pathogenesis of hematologic disorders such as aplastic anemia and the development of neoplasia are believed to involve dysregulation of apoptosis. To quantitate accurately the proportion of apoptosis cells within different cell types of a heterogeneous cell population such as blood or bone marrow, a method is required that combines the analysis of large numbers of cells with concurrent immunophenotyping of cell surface antigens. In this study, we have evaluated such a method using the fluorescent DNA binding agent, 7-amino actinomycin D (7AAD), to stain three diverse human cell lines, induced to undergo apoptosis by three different stimuli. Flow cytometric analysis defines three populations on the basis of 7AAD fluorescence and forward light scatter. We have shown by cell sorting and subsequent morphological assessment and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling that the populations defined by 7AAD represent live, apoptotic, and late-apoptotic/dead cells. This method is quick, simple, reproducible, and cheap and will be a valuable tool in the investigation of the role of apoptosis in normal physiology and in disease states.  相似文献   
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BACKGROUND: This study evaluated serum vascular endothelial growth factor (VEGF) concentrations in women with normal intrauterine pregnancy (IUP), arrested IUP and ectopic pregnancy (EP). METHOD: This was a prospective, case-control study evaluating serum VEGF concentrations among 45 early pregnant women who subsequently were found to have an EP, a normal IUP or an arrested IUP (15 women in each group). Patients were stratified according to serum VEGF concentrations above and below 200 pg/ml. RESULTS: There was a significant difference in VEGF concentrations among women with EP, arrested IUP and normal IUP (306.1 +/- 26.5, 169.7 +/- 16.6 and 27.0 +/- 4.4 pg/ml respectively, P < 0.001). With a cut-off concentration of 200 pg/ml, serum VEGF could distinguish normal IUP from EP with a sensitivity of 88%, a specificity of 100% and a positive predictive value of 100%. Between EP and arrested IUP, the sensitivity was 87.5%, specificity 75% and positive predictive value of 77.8%. CONCLUSIONS: VEGF is a potential marker for EP. Its concentrations in women with EP are higher than in those with normal and arrested IUP.  相似文献   
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