目的 探讨CD25单抗在无血缘关系造血干细胞移植（UHSCT）中对干细胞植入和移植物抗宿主病（GVHD）的作用。方法 27例UHCST中，移植后1、4d给予CD25单抗1mg/kg。结果 27例中，除1例早期死亡外，26例患者造血全部重建。17例发生急性GVHD，其中Ⅱ度以上急性GVHD6例（23％）。复发3例，严重感染3例。26例可评价患者中，19例无病生存（73％）。结论 CD25单抗在UHSCT中对保证干细胞植入和预防GVHD有肯定的作用，白血病复发并不增加。此研究为UHCST和HLA不合的造血干细胞移植提供一个可选择的途径。

A mobile Ad-hoc network (MANET) is a dynamic multi hop wireless network established by a group of nodes in which there is no central administration. Due to mobility of nodes and dynamic network topology, the routing is one of the most important challenges in ad-hoc networks. Several routing algorithms for MANETs have been proposed by the researchers which have been classified into various categories, however, the most prominent categories are proactive, reactive and hybrid. The performance comparison of routing protocols for MANETs has been presented by other researcher also, however, none of these works considers proactive, reactive and hybrid protocols together. In this paper, the performance of proactive (DSDV), reactive (DSR and AODV) and hybrid (ZRP) routing protocols has been compared. The performance differentials are analyzed on the basis of throughput, average delay, routing overhead and number of packets dropped with a variation of number of nodes, pause time and mobility.

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A Comprehensive Performance Analysis of Proactive, Reactive and Hybrid MANETs Routing Protocols

The dynamic topology of a mobile ad hoc network (MANET) poses a real challenge in the design of a MANET routing protocol. Over the last 10 years, a variety of routing protocols have been developed and their performance simulations are made by network researchers. Most of the previous research on MANET routing protocols have focused on simulation study by varying network parameters, such as network size (node density), pause times, or node mobility independently. This paper considers the problem from a different perspective, using a simulation model the combined effect of node density and packet length; node density and mobility on the performance of a typical 802.11 MANET is investigated. This is a common and realistic scenario in MANETs where nodes move around, join and leave the network at any time. Based on the QoS (end-to-end delay, throughput), routing load and packet retransmissions, this paper systematically analyzes the performance of four diverse MANET routing protocols with the different simulation model and configurations, and drew more complete conclusions.

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A study of MANET routing protocols: Joint node density, packet length and mobility

The primary objective of this research work is to study and investigate the performance measures of Reactive protocols (AODV, TORA) and Proactive protocols (DSDV) routing protocols of MANET using TCP & CBR based traffic models. In this paper we will simulate the environment used for analyzing, evaluating and implementing AODV, DSDV and TORA routing protocols in MANET, to analyze the performance of above said protocols based on Packet Delivery Ratio, Average End-to-End Delay and Throughput. We will investigate the effect of change in number of nodes on MANET routing protocols. Here, we will analyze and compare the performance of MANET routing protocols based on both CBR and TCP based traffic patterns. We have used the NS-2 simulator for performing various simulations and used awk scripts for analyzing the results.

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Traffic Pattern based performance comparison of Reactive and Proactive protocols of Mobile Ad-hoc Networks

Mobile Ad-hoc Network is an infrastructure less and decentralized network which need a robust dynamic routing protocol. Many routing protocols have been proposed to accommodate the needs of communications for MANET. In this paper, we have compared the performance of traditional proactive DSDV routing protocol along with on-demand reactive routing protocols for MANET: AODV. From analysis, the On-demand protocol, AODV has given better performance than table driven DSDV routing protocol. To compare the performance of DSDV and AODV routing protocol, the simulation results were analyzed by graphical manner and trace file based on QoS metrics such as Delay, Jitter. The performance differentials have been analyzed based on network load, mobility, and network size. The simulation result analysis verifies the DSDV and AODV routing protocol performances.

Performance evaluation of DSDV and AODV routing protocols in Mobile Ad-hoc Networks

Ad hoc networks are characterized by multihop wireless connectivity, frequently changing network topology and the need for efficient dynamic routing protocols plays an important role. We compare the performance of two prominent on-demand routing protocols for mobile ad hoc networks: Dynamic Source Routing (DSR), Ad Hoc On-demand distance Vector Routing (AODV). A detailed simulation model with MAC and physical layer models is used to study the interlayer interactions and their performance implications. We demonstrate that even though DSR and AODV share similar on-demand behavior, the differences in the protocol mechanisms can lead to significant performance differentials. In this paper we examine two on demand routing protocols AODV and DSR based on packet delivery ratio, normalized routing load, normalized MAC load, average end to end delay by varying the number of sources, speed and pause time.

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Geetha Jayakumar

Papers

Performance Comparison of Two On-demand Routing Protocols for Ad-hoc Networks based on Random Way Point Mobility Model