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71.
BV Murthy AS Muerhoff SM Desai SN Natov BA Bouthot R Ruthazer CH Schmid AS Levey IK Mushahwar BJ Pereira 《Canadian Metallurgical Quarterly》1998,53(6):1769-1774
The etiology of liver disease remains unknown in about 4 to 23% of dialysis patients and 10 to 16% of renal transplant recipients. A search for other causative agents of liver disease led to the discovery of the GB group of viruses. We studied the association between the presence of GB virus C (GBV-C) infection, known risk factors for parenterally-transmitted infections and history or laboratory evidence of liver disease among end-stage renal disease (ESRD) patients referred for renal transplantation to the New England Organ Bank, MA. Stored sera from patients on the renal transplantation waiting list between November 1986 and June 1990 were tested for antibody to hepatitis C virus (HCV). Sera were available in 1544 of 3243 (48%) patients, and anti-HCV was detected by ELISA3 in 287 (19%). All 287 anti-HCV positive patients formed the anti-HCV positive cohort and 286 randomly selected anti-HCV negative patients formed the anti-HCV negative cohort (573 patients overall). Additional sera were available for GBV-C RNA testing in 465 of 573 (81%) patients, and GBV-C RNA was detected by RT-PCR in 146. The overall extrapolated prevalence of serum GBV-C RNA was 29%. The prevalence of serum GBV-C RNa among anti-HCV positive patients (35%) was not significantly different from that among anti-HCV negative patients (29%; P = 0.22). In a univariate analysis, compared to patients without GBV-C RNA, patients with serum GBV-C RNA were younger [odds ratio (OR) 0.98 per year of age, P = 0.01], had a lower proportion of males (OR 0.64, P = 0.03), lower proportion of patients with diabetes mellitus (OR 0.44, P = 0.01), higher proportion of patients with a previous transplantation (OR 1.53, P = 0.04), longer duration of dialysis at the time of enrollment (OR 1.004 per month on dialysis, P = 0.03), and a higher proportion of patients with history of transfusions (OR 4.58, P = 0.01). Serum GBV-C RNA was not associated with a significantly increased OR for history of liver disease or non-A, non-B hepatitis, or elevated serum alanine aminotransferase levels. In a step-wise multivariate regression analysis, a younger age (OR 0.98 per year of age, P = 0.03), and history of blood transfusions (OR 3.89, P = 0.03) were associated with an increased OR for serum GBV-C RNA, while diabetes mellitus was associated with a decreased OR for GBV-C RNA (OR 0.47, P = 0.01). Anti-HCV was not a predictor of serum GBV-C RNA (OR 1.07, P = 0.77). The results of this study support the fact that GBV-C is a parenterally transmitted virus and shed light on the modes of transmission of GBV-C among ESRD patients. However, the association with liver disease remains to be established. 相似文献
72.
73.
AS Stein MR O'Donnell A Chai GM Schmidt A Nademanee PM Parker EP Smith DS Snyder A Molina DE Stepan R Spielberger G Somlo KA Margolin N Vora J Lipsett J Lee J Niland SJ Forman 《Canadian Metallurgical Quarterly》1996,14(8):2206-2216
PURPOSE: To evaluate in a prospective study the efficacy of autologous bone marrow transplantation (BMT) in adult patients with acute myelogenous leukemia (AML) in first remission, using a single course of high-dose Cytarabine (HD Ara-C) consolidation therapy as in vivo purging. PATIENTS AND METHODS: Sixty consecutive adult patients with AML in first complete remission (CR) were treated with HD Ara-C consolidation therapy as a method of in vivo purging before marrow collection. High-dose therapy consisted of fractionated total-body irradiation (FTBI) 12 Gy, intravenous etoposide 60 mg/kg, and cyclophosphamide 75 mg/kg, followed by reinfusion of cryopreserved marrow. RESULTS: Sixty patients underwent consolidation treatment with HD Ara-C with the intent to treat with autologous BMT. Sixteen patients were unable to proceed to autologous BMT (10 patients relapsed, one died of sepsis, one developed cerebellar toxicity, two had inadequate blood counts, and two refused). Forty-four patients underwent autologous BMT and have a median follow-up time of 37 months (range, 14.7 to 68.7) for patients who are alive with no relapse. The cumulative probability of disease-free survival (DFS) at 24 months in the intent-to-treat group is 49% (95% confidence interval [CI], 37% to 62%) and in those who actually underwent autologous BMT is 61% (95% CI, 46% to 74%). The probability of relapse was 44% (95% CI, 31% to 58%) and 33% (95% CI, 20% to 49%) for the intent-to-treat and autologous BMT patients, respectively. CONCLUSION: This approach offers a relatively high DFS rate to adult patients with AML in first CR. The results of this study are similar to those achieved with allogeneic BMT. 相似文献
74.
The present study investigates 1085 previously untreated patients with squamous cell carcinoma of the head and neck for factors that influence recurrence following treatment with definitive radiotherapy. In the second part of this study, those diagnosed with recurrence were studied with regard to treatment and were further analysed with regard to identification of prognostic factors which may affect outcome in the patient who actually develops a recurrence. 相似文献
75.
LS Melchers M Apotheker-de Groot JA van der Knaap AS Ponstein MB Sela-Buurlage JF Bol BJ Cornelissen PJ van den Elzen HJ Linthorst 《Canadian Metallurgical Quarterly》1994,5(4):469-480
A novel chitinase gene of tobacco was isolated and characterized by DNA sequence analysis of a genomic clone and a cDNA clone. Comparative sequence analysis of both clones showed an identity of 94%. The proteins encoded by these sequences do not correspond to any of the previously characterized plant chitinases of classes I-IV and are designated as class V chitinases. Comparison of the chitinase class V peptide sequence with sequences in the Swiss Protein databank revealed significant sequence similarity with bacterial exo-chitinases from Bacillus circulans, Serratia marcescens and Streptomyces plicatus. It was demonstrated that class V chitinase gene expression is induced after treatment of tobacco with different forms of stress, like TMV-infection, ethylene treatment, wounding or ultraviolet irradiation. Two related chitinase class V proteins of 41 and 43 kDa were purified from Samsun NN tobacco leaves inoculated with tobacco mosaic virus. The proteins were purified by Chelating Superose chromatography and gel filtration. In vitro assays demonstrated that class V chitinases have endo-chitinase activity and exhibit antifungal activity toward Trichoderma viride and Alternaria radicina. In addition, it was shown that class V chitinase acts synergistically with tobacco class I beta-1,3-glucanase against Fusarium solani germlings. 相似文献
76.
V. A. Ashikhmen V. G. Buchatskii N. V. Dmitriev L. I. Malyshev 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1989,23(1):47-53
1. | The side curtains as necessary cutoff elements of the al-Qadisiyah hydro development were made in an optimal design variant, on time, and with a high quality. A considerable technical and economic effect was obtained by eliminating excessive volumes of works specified by the original design as a result of a combined analysis of the data of engineering surveys, investigations of experimental grouting works, and optimization of the grouting technology. |
2. | The index of unit cement absorption in the control holes used as the criterion of sufficiency of grouting on the side curtains should be used everywhere where the purpose of grouting works is to detect and eliminate large cavities and fissures. |
3. | Grouting works on elimination of karst cavities and large fissures, being in essence infill grouting, require the development of an industrial technology of the works with the use of considerable volumes of grouts (concretes) and use of a large number of machines and mechanisms (concrete plants, mixers, concrete pumps, etc.). |
77.
V. V. Rukin N. V. Dmitriev V. E. Kuznetsov A. D. Sotnikov 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1988,22(7):390-394
1. | Polymer-cement shotcrete (gunite) has a number of advantages in comparison with ordinary shotcrete — increased elasticity (low modulus of deformation), high impermeability and adhesiveness to rocks and concrete, resistance to corrosive effects, nontoxicity of the polymer used, and simplicity of the technology of adding latex to the coating material. |
2. | The addition of polymer makes it possible to reduce the thickness of the coating by at least half while preserving the strength and operating characteristics of the support, which provides a high cost effectiveness of using polymer-cement shotcrete. |
3. | It is expedient to recommend the wide use of highly effective polymer-cement compositions on a base of synthetic latex SKS-65GP in hydrotechnical construction. |
78.
A. F. Dmitriev A. I. Tyshenko N. N. Khlapuk 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1992,26(5):306-310
1. | It is necessary to correlate the value of the noneroding velocity with the time of flood passage. If canals are planned in regions where comparatively brief summer floods are dominant, the value of the noneroding velocity should be taken equal to 3 m/sec since by the start of the flood the grass cover will have time to develop and reach maximum strength. If the canals are to be constructed in regions where spring floods are dominant, for example, in the northwestern regions of the country, then the noneroding velocity should be taken equal to 1.5 m/sec, since by the start of the flood the grass carpet does not have time to develop and become stronger. |
2. | In the absence of a constant runoff in the canal, for example, drainage canals, it is necessary to revet the bottom and side slopes with grass carpets. |
3. | In the presence of a constant moistening is made from traditional materials, in the zone of alternate moistening and above it, it is necessary to revet the slopes within reinforced grass carpet. |
4. | In a hydraulic calculation of canals with revetment of the bottom and side slopes with grass carpet, it is necessary to determine the roughness coefficient from the graph of n=f(VR, i). In a hydraulic calculation of wide overgrown channels and in calculation of the movement of the flow over floodplain stretches of rivers free from shrubs and trees, it is necessary to determine the roughness coefficient from the graph of n=f(Vh, i). |
5. | Calculation of canals with nonuniform roughness (rigid revetment and revetment by grass carpets) must be carried out on the basis of relations of uniform flow by means of a generalized roughness coefficient. |
79.
V. P. Shcherbakov I. B. Tsyganov O. Yu. Dmitriev T. I. Polyakova 《Fibre Chemistry》2007,39(4):285-288
An exact differential equation for the equilibrium of an elastic fibre loaded on the free end with a concentrated force and
over the entire length of the elastic line of the distributed power load caused by the weight of the fibre was obtained in
conditions of large movements. A method was developed for determining the flexural rigidity of the fibre which consists of
bending the fibres and numerically solving the equation from the geometric nonlinear theory of bending of elastic fibres.
__________
Translated from Khimicheskie Volokna, No. 4, pp. 19–21, July–August, 2007. 相似文献
80.
A strategy of industrial-scale manufacture for a wide range of carbon materials based on carbon nanofibers is proposed. It was shown that porous materials with a high sorption capacity can be obtained with the use of carbon nanofibers by means of conventional manufacturing operations. The results of studying of consolidation of carbon nanofibers with pyrolytic carbon are reported. It was found that the nature of carbon material has a substantial effect on the rate of deposition of pyrolytic carbon. The most appropriate temperature range in which carbon nanofibers should be consolidated for the preparation of materials with a high catalytic activity was determined. 相似文献