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71.
T Tasaka JW Said R Morosetti D Park W Verbeek M Nagai J Takahara HP Koeffler 《Canadian Metallurgical Quarterly》1997,89(5):1686-1689
Controversy exists as to whether Kaposi's sarcoma-associated herpesvirus (KSHV) is more widespread than originally reported. Recently, Monini et al reported that KSHV is ubiquitous in urogenital and prostate tissues and sperm of healthy Italian adults using nested polymerase chain reaction (PCR). We have examined for the presence of KSHV in 10 normal prostates from Italian men and 10 from men from the United States, as well as 32 prostatic, 30 vulvar, 24 ovarian, 20 cervical, and 30 testicular cancer specimens from patients from the United States. None of the patients had a history of human immunodeficiency virus infection. The samples were tested by nested PCR. The sensitivity of this assay was determined by a dilution study performed by diluting KSHV DNA from the KS-1 cells (a primary effusion lymphoma cell line which is estimated to have 16 copies of KSHV per cell) in DNA from a K562 myeloid cell line. The nested PCR that we used can detect 2.4 copies of KSHV sequences on a background of K562 DNA. All the samples were negative for KSHV sequences. Therefore, we cannot confirm the finding that KSHV sequences are ubiquitous in urogenital and prostate tissues. Furthermore, because our samples were from both the United States and Italy, the discrepancy between results is unlikely to be explained by either ethnic or environmental factors. False-positive results easily occur using nested primer PCR because of contamination. Our data argue that KSHV is not widely disseminated in urogenital tissues from nonimmunosuppressed individuals. 相似文献
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CH Schmid RB D'Agostino JL Griffith JR Beshansky HP Selker 《Canadian Metallurgical Quarterly》1997,50(11):1219-1229
When outcomes occur in clinical trials before treatment can be given, neither intent-to-treat nor according-to-protocol analyses give optimal estimates of the treatment effect. A better approach employs a time-dependent variable for treatment. Intent-to-treat analyses are conservative, biasing against treatment; according-to-protocol analyses bias in favor of treatment. We show how to measure the effect of a time-dependent variable in a logistic regression using person-time intervals as units of measurement and describe appropriate methods for reporting model performance. The method is applied to develop a model to predict the probability that a patient with a myocardial infarction will have a sudden cardiac arrest within 48 hours of presentation to emergency medical services both when treated with thrombolysis and when not treated. We use a time-dependent treatment variable because many patients went into cardiac arrest while awaiting treatment. This technique has been programmed into an electrocardiograph for real-time use in an emergency department. 相似文献
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Z Mátrai G Lelkes J Milosevits HP Páldiné K Pecze 《Canadian Metallurgical Quarterly》1997,138(33):2075-2080
Authors report effective treatment of T-cell large granular lymphocyte (LGL) leukaemia and secondary pure cell aplasia with cyclophosphamide. The current classification of LGL proliferations is presented, with emphasis on the issues of diagnosis, clinical course and treatment. LGL proliferations are not so rare that previously thought and should be involved in the differential diagnosis of neutropenia, pure red cell aplasia, Felty's syndrome and vasculitis of unknown origin. 相似文献
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C Schleper G Puehler I Holz A Gambacorta D Janekovic U Santarius HP Klenk W Zillig 《Canadian Metallurgical Quarterly》1995,177(24):7050-7059
Two species belonging to a novel genus of archaea, designated Picrophilus oshimae and Picrophilus torridus, have been isolated from two different solfataric locations in northern Japan. One habitat harboring both organisms was a dry, extremely acidic soil (pH < 0.5) that was heated by solfataric gases to about 55 degrees C. In the laboratory both species grew heterotrophically on yeast extract and poorly on tryptone under aerobic conditions at temperatures between 45 and 65 degrees C; they grew optimally at 60 degrees C. The pH optimum was 0.7, but growth occurred even around pH 0. Under optimal conditions, the generation time was about 6 h, yielding densities of up to 10(10) cells per ml. The cells were surrounded by a highly filigreed regular tetragonal S-layer, and the core lipids of the membrane were mainly bis-phytanyltetraethers. The 16S rRNA sequences of the two species were about 3% different. The complete 16S rRNA sequence of P. oshimae was 9.3% different from that of the closest relative, Thermoplasma acidophilum. The morphology and physiological properties of the two species characterize Picrophilus as a novel genus that is a member of a novel family within the order Thermoplasmales. 相似文献
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A case of sacrococcygeal teratoma is presented with characteristics of fetus-in-fetu. This pseudo-fetus presented a rudimentary single cavity heart, which beat at a different rate to that of the affected infant. X-ray examination showed no spinal column. This case confirms that fetus in fetu can be a remarkably complex, well-differentiated, highly organized teratoma. 相似文献