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981.
L Lombardo D Rota Scalabrini P Vineis M De La Pierre 《Canadian Metallurgical Quarterly》1993,4(3):245-250
BACKGROUND: Lymphoproliferative disorders in patients with liver cirrhosis, although uncommon, have been reported in at least 49 cases. Some authors have suggested that the association between chronic liver disease and lymphoma is not coincidental, that immune mechanisms may be pathogenetically involved. PATIENTS AND METHODS: In the present study we calculated the incidence rate of lymphoproliferative disorders in 334 liver cirrhosis patients (201 males, mean age 59 +/- 12; 133 females, mean age 61 +/- 11) treated at the Gastroenterology Department of the Mauriziano Hospital in Turin from January 1987 to September 1990. RESULTS: We diagnosed 12 lymphoproliferative disorders, corresponding to an incidence of 9.56/1,000 person-years, a figure much higher than expected on the basis of the incidence rate registered in the Turin general population. Six of the 12 lymphoproliferative disorders were non-Hodgkin's lymphomas of the stomach, a proportion by far exceeding expectation. CONCLUSIONS: Our data support the hypothesis that the association between chronic liver disease and lymphoproliferative disorders is not just coincidental, and suggest that liver cirrhosis might be considered an immunological disturbance which entails an increased risk of developing lymphoproliferative disorders. Mechanisms causing lymphoproliferative disorders to develop in the course of chronic liver disease have been hypothesized. 相似文献
982.
A simple mathematical model applied to selection of the sodium profile during profiled haemodialysis
L Colì M Ursino V Dalmastri F Volpe G La Manna G Avanzolini S Stefoni V Bonomini 《Canadian Metallurgical Quarterly》1998,13(2):404-416
BACKGROUND: Among dialysis patients in the last 10 years the incidence of intradialytic dysequilibrium syndrome and symptomatic hypotension has increased significantly. Profiled haemodialysis (PHD), a new dialysis technique based on intradialytic modulation of the dialysate sodium concentration according to pre-elaborated individual profiles, has been set up to reduce intradialytic imbalances and the incidence of dysequilibrium syndrome and symptomatic hypotension. The present paper illustrates a new mathematical model for solute kinetics, single-compartment for sodium and two-compartment for urea, aimed at improving the use of PHD. The model allows the sodium profile to be elaborated a priori, before each dialysis session, according to the patient's clinical needs and respecting the individual sodium mass removal and weight gain. METHOD: The mathematical model was first derived and then applied to determining a rational dialysate sodium profile. A procedure which allows the method to be tuned to individual clinical needs on the basis of routine measurements performed before each session is also presented. The proposed method was validated in vivo during seven dialysis sessions, each performed on a different patient. RESULTS: The comparison between data predicted by the model and those obtained in vivo shows a good correspondence in particular concerning the time pattern of blood urea and sodium. The comparison between the model prediction and in vivo determined sodium and urea plasma curves showed standard deviations (2.25 mEq/l for sodium and 0.87 mmol/l for urea) only slightly higher than those attributable to laboratory measurement errors. Moreover, in vivo implementation of PHD by our model enables one to remove an amount of sodium mass comparable with the a priori quantity predicted by the model. 相似文献
983.
984.
Gubello G. La China M. Scandale W. 《Applied Superconductivity, IEEE Transactions on》2004,14(2):231-234
This paper presents the results of a comprehensive analysis, from the geometric point of view, of the pre-series LHC dipoles. The progressive change of the imposed magnet shape has been monitored from the first assembly stage until after the cold test. Data concerning the error on sagitta, extremity positions and sextupolar corrector positions are provided for the pre-series magnets. Implications of aligning out-of-tolerance dipoles by the extremities are also discussed. 相似文献
985.
986.
Summary The hydrolysis of bisphenol A polythiocarbonate is studied under phase transfer conditions, and occurs principally in the organic phase, influenced by the catalysts according to their structure.For part 6, see the preceding paper 相似文献
987.
Francesco P. La Mantia 《Polymer Engineering and Science》1987,27(22):1713-1715
A modification of the kinetics equation of mechanical degradation of Harrington and Zimm is proposed to fit experimental data taken on a molten polystyrene. This equation is applied to each molecular weight of the discretized molecular weight distribution curve, and the limiting molecular weight is determined for each molecular weight. With this modification the theoretical curves fit both Mw and Mn curves well. 相似文献
988.
989.
Ramjee R. Varadhan K. Salgarelli L. Thuel S.R. Shie-Yuan Wang La Porta T. 《Networking, IEEE/ACM Transactions on》2002,10(3):396-410
Mobile IP is the current standard for supporting macromobility of mobile hosts. However, in the case of micromobility support, there are several competing proposals. We present the design, implementation and performance evaluation of HAWAII (handoff-aware wireless access Internet infrastructure), a domain-based approach for supporting mobility. HAWAII uses specialized path setup schemes which install host-based forwarding entries in specific routers to support intra-domain micromobility. These path setup schemes deliver excellent performance by reducing mobility related disruption to user applications. Also, mobile hosts retain their network address while moving within the domain, simplifying quality-of-service (QoS) support. Furthermore, reliability is achieved through maintaining soft-state forwarding entries for the mobile hosts and leveraging fault detection mechanisms built in existing intra-domain routing protocols. HAWAII defaults to using Mobile IP for macromobility, thus providing a comprehensive solution for mobility support in wide-area wireless networks 相似文献
990.
Giovanni Busatto Roberto La Capruccia Francesco Iannuzzo Francesco Velardi Roberto Roncella 《Microelectronics Reliability》2003,43(4):577-583
A new on-chip non-invasive integrated current sensing, compatible with standard CMOS technology, has been developed, using a 1.2 μm BiCMOS ALCATEL technology, to sense the current in the drain side of a power MOSFET. The circuit is based on a split-drain magnetic sensor, implemented on the same chip of an integrated gate driver for a power MOSFET. A CMOS biasing circuit with a differential current output is also developed. The simulation results of the current sensing show a conversion gain of 1.25 mV/mT. 相似文献