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71.
Summary Junín virus establishes a long-term persistent infection in its natural host,Calomys musculinus. Virus recovered from blood of infected animals from 14 to 61 days p.i. behaved antigenically distinct to parental virus, as shown by cross neutralization assays. The emergence of antigenic viral variants occurs during both the acute and persistent state of infection.With 1 Figure  相似文献   
72.
Enterocin CRL35 is an antibacterial polypeptide of 3.5×103 Da produced by Enterococcus faecium CRL35. A series of experiments are described that show the enterocin also had antiviral activity against thymidine-kinase positive (tk+) and deficient (tk) strains of herpes simplex (HSV) type 1 and 2 in Vero and BHK-21 cells. This activity was observed at 100 μg/ml, 15-fold lower than the cytotoxic concentration. In both cell lines there was a 2 log inhibition of infectivity. The compound inhibited viral multiplication in a dose-dependent manner and had no virucidal effect. Enterocin CRL35 also inhibited the virion-associated host shutoff in infected Vero cells showing that intracellular viral multiplication was affected.  相似文献   
73.
74.
In the presence of cardiac cysts we must discard a hydatid disease, even if there is no involvement of other organs. Imaging techniques are useful for guiding the initial diagnosis. The presence of daughter vesicles or multiple cysts is very characteristic. We present a patient affected by cardiac hydatid disease, in the form of multiple cardiac cysts, without extracardiac affectation, who presented pericardial chest pain. The patient was dealt with surgery to avoid the risks of a cyst rupture.  相似文献   
75.
Mucormycosis is an aggressive, rare and opportunistic infectious disease, with a high mortality rate. Etiologic agents are filamentous fungi, and infection among humans normally occurs through spore inhalation. A 61-year-old male individual, presenting left eye amaurosis, dark epistaxis, hyperalgesia and malodor underwent clinical examination, which detected ulcerative lesion and wide bone exposure in the hard palate and alveolar ridge. Direct microbiological examination, microbiological culture and lesion biopsy were performed. Non-septate smooth fungal hyphae forming right angles with each other were observed through the direct microbiological examination. Microbiological culture revealed fast-growing fungal colonies with cottony texture, identified as Rhizopus sp. Histopathological examination exhibited necrosis areas, intense mononuclear inflammatory infiltrate and bulky hyphae, thus concluding the mucormycosis diagnosis. Amphotericin B antifungal therapy and surgical intervention were adopted as treatment. The patient was then rehabilitated with maxillofacial prosthesis, subsequently to the healing of the surgical wound.  相似文献   
76.
BACKGROUND: Peripheral blood progenitor cells (PBPCs) are commonly collected and used to reconstitute hematopoiesis after high-dose chemotherapy. However, strategies for optimal collection and assessment of leukapheresis components are not standardized. STUDY DESIGN and METHODS: Hematopoietic progenitor cell assays were performed on 369 leukapheresis components collected from 95 patients who had received doxorubicin-based chemotherapy and/or granulocyte-colony-stimulating factor (G-CSF). Precollection patient hematologic values, leukapheresis collection values, component hematopoietic progenitor cell assays, and patient outcome measures were summarized. The kinetics of mononuclear cell (MNC) and PBPC mobilization were assessed among four patient groups. RESULTS: Patient group was a significant predictor of the peripheral blood MNC count on the day of collection (p<0.0001), and that value was a significant predictor of granulocyte-macrophage– colony-forming unit (CFU-GM) yield (p<0.0001). This relationship between the peripheral blood MNC count on the day of collection and CFU- GM yield differed according to patient group (p<0.0001). CFU-GM made up a larger fraction of peripheral blood MNCs collected from patients who received chemotherapy plus G-CSF than collected from those who received G-CSF alone. Moreover, the peripheral blood MNC count and the corresponding CFU-GM yield increased significantly on consecutive days of collection in patient groups receiving chemotherapy and G-CSF but were unchanged or decreased in patients receiving G-CSF alone. CONCLUSION: The relationship between peripheral blood MNC count and leukapheresis component CFU-GM yield differed significantly between patients who received chemotherapy and G-CSF and those who received G- CSF alone for the mobilization of PBPCs. Patient peripheral blood MNC count and component CFU-GM yield are useful for both assessing and suggesting revisions to PBPC mobilization and collection strategies.  相似文献   
77.
预激态补骨脂素抑制 K562细胞增殖的实验研究   总被引:6,自引:0,他引:6  
本研究的目的是观察预激态补骨脂素对K562细胞增殖的影响,为补骨脂素的临床应用提供实验依据。取预激态补骨脂素和晚激态补骨脂素处理的细胞,在培养后检测台盼蓝拒染细胞数和白血病细胞集落,并对它们在台盼蓝拒染细胞抑制率(TBIR)、细胞增殖抑制率(CPIR)和集落形成抑制率(CFIR)方面的差异进行比较。结果表明:预激态补骨脂素对K562细胞增殖有抑制作用;随着预激态补骨脂素浓度的增加,其抑制作用也随之增强;预激态补骨脂素与晚激态补骨脂素的TBIR、CPIR、CFIR各值比的差异不显著;为使预激态补骨脂素要充分发挥对K562细胞的抑制作用,补骨脂素的紫外线照射时间应在10分钟以上;与K562细胞作用时间也应大于12小时;抑制作用会因预激态补骨脂素预激后搁置时间的延长而下降,在6小时内作用最强。结论:预激态补骨脂素和晚激态补骨脂素对K562细胞的增殖均表现出抑制作用,有望作为临床的抗肿瘤用药。  相似文献   
78.
BACKGROUND: Testing for antibody to hepatitis B core antigen (anti-HBc) as a surrogate for hepatitis C viremia is no longer needed for blood donor screening. Currently, the important question is how much its use supplements hepatitis B surface antigen (HBsAg) donor screening in preventing transfusion-transmitted hepatitis B virus (HBV) infection. STUDY DESIGN AND METHODS: In a study conducted in the 1970s, 64 blood donors were associated with 15 cases of HBV (1.0%) in 1533 transfusion recipients. Sera from 61 donors at donation and 29 follow-up visits were available for present-day assays for HBsAg, HBV DNA, anti-HBc, and antibody to HBsAg (anti-HBs). RESULTS: HBsAg was found in four previously negative blood donors; HBV DNA was limited to three of these four. Anti-HBc was detected in six HBsAg-negative donors. Two other donors were negative in all assays at donation, but positive for anti- HBc and anti-HBs 2 to 4 months later. The remaining donors were negative for all HBV markers, which left five recipient cases unexplained. No HBV transmission was observed when anti-HBs sample-to- negative control values were > or = 10. CONCLUSION: Some 33 to 50 percent of cases of hepatitis B that could be transmitted by transfusion of blood from HBsAg-negative donors are prevented by anti- HBc screening. Anti-HBc-positive donors unequivocally positive for anti- HBs should be considered noninfectious for HBV and should be allowed to donate. Anti-HBc screening of paid plasmapheresis donors, supplemented by anti-HBs testing, would reduce the amount of HBV to be processed by virus inactivation and increase the content of anti-HBs in plasma pools.  相似文献   
79.
Percutaneous umbilical blood samples (PUBS), obtained under ultrasound guidance, are used for prenatal diagnosis and management of hemolytic disease of the newborn (HDN) and other fetal disorders. Rapid testing at the time of sampling is vital to distinguish fetal from maternal blood. Blood typing was performed by slide technique in the treatment room during 38 procedures on 25 patients. Anti-I was used to test 50 presumed PUBS; venous I-positive maternal blood was tested in parallel. Because anti-I cannot detect fetal blood after umbilical vein transfusion (UVT) of I-positive donor blood, ABO and Rh blood typing reagents were used to test 29 samples when maternal and fetal or donor blood groups differed. Monoclonal reagents were used for optimal detection of weak AB antigens in fetal blood. Avid, chemically modified anti-D was used for Rh typing. Blood typing showed 27 (34%) of 79 samples to be maternal blood. Fetal blood was obtained in 8 of 10 cases investigated for fetal disorder and in 16 cases of potential HDN (anti-D, 5; -CD, 5; -cE, 2; -K, 2; -c; -E). The absence of HDN (antigen-negative fetus) was determined in 4 cases. UVT afforded live birth of 9 of 10 infants with HDN and was not indicated in two cases.  相似文献   
80.
BACKGROUND: Hepatitis virus(es) that are neither hepatitis B (HBV) nor hepatitis C (HCV) (non-B, non-C [NBNC]) may be transmitted by transfusion. The present study assessed donor values for alanine aminotransferase (ALT) and antibody to hepatitis B core antigen (anti- HBc) for their association with HCV and NBNC hepatitis outcomes among allogeneic blood recipients. STUDY DESIGN AND METHODS: Data on blood donors and recipients enrolled in the Transfusion- Transmitted Viruses Study in four United States cities from 1974 through 1980 were supplemented by anti-HBc testing of donors and anti-HCV evaluation of recipients. Two statistical approaches estimated the value of these indirect tests in detecting donors associated with HCV seroconversion and NBNC hepatitis in recipients. RESULTS: For HCV cases, donor ALT alone (at > or = 60 IU/L) had a sensitivity and a specificity of 30 and 96 percent, respectively, and anti-HBc alone (at > or = 60% inhibition) had a sensitivity and specificity of 53 and 86 percent, respectively. The two markers combined had a sensitivity and a specificity of 69 and 83 percent. For NBNC hepatitis cases, each measure had low sensitivity (20%) that was not improved by using both (28%) [corrected]. CONCLUSION: The indirect tests proved to be equal in sensitivity to the first-generation anti-HCV tests. The positive predictive power of these indirect tests in the 1980s was sufficient to affect HCV incidence in studies during that period. Improved anti-HCV assays, however, replaced the need for indirect tests. The sensitivity of indirect tests for NBNC hepatitis contributed little.  相似文献   
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