Self-expanding metallic stents of a modified Gianturco design were used for palliative treatment of malignant esophagogastric strictures. Over a 10-month period, 10 stents were placed in nine patients. All patients with severe dysphagia due to malignant strictures in whom all other treatment options had failed were candidates for these stents. Neither extensive length of esophageal involvement nor complete esophageal obstruction was a contraindication. All stents were placed with fluoroscopic guidance without any technical failures or procedural morbidity or mortality. Mild reflux occurred in three patients in whom the stent tubes straddled the distal esophageal sphincter. Five patients were still alive after 1-8 months. The remaining four patients died 6-28 weeks after stent placement; all stents were patent at the time of death. These stents are easy to insert, safe, and reasonably effective for short-term palliative treatment of esophagogastric neoplasms.

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A series of multicomponent Zr 0.5 Ti 0.5 Mn 0.4 V 0.6 Ni 0.85 M 0.15 ͑M ϭ Fe, Co, Cu, Mo, and Al͒ alloys are prepared and their crystal structure and pressure-composition-temperature curves are examined. The electrochemical properties of these alloys such as discharge capacity, cycling performance, and rate capability are also investigated. Zr 0.5 Ti 0.5 Mn 0.4 V 0.6 Ni 0.85 M 0.15 ͑M ϭ Fe, Co, Cu, Mo, and Al͒ alloys have predominantly C14 Laves phases multiple phase structure. The alloys with M ϭ Co and Fe have relatively larger hydrogen storage capacities. The discharge capacities just after activation are relatively large in the case of the alloys with M ϭ Co and Fe. They are 226 and 225 mAh/g, respectively, at the current density 60 mA/g. The Zr 0.5 Ti 0.5 Mn 0.4 V 0.6 Ni 0.85 Co 0.15 alloy is the best one with a relatively large discharge capacity and good cycling performance. The gradual increases in the discharge capacities of the alloys with the increase in the current density ͑from 60 to 250 mA/g͒ are considered to result from the spontaneous hydrogen evolution due to an insufficient hydrogen overvoltage. During activation Ni-rich and Fe-rich regions form on the surface of the Zr 0.5 Ti 0.5 Mn 0.4 V 0.6 Ni 0.85 Fe 0.15 alloy. They may act as active sites for the electrochemical reaction. With the increase in the number of charge/discharge cycles for the Zr 0.5 Ti 0.5 Mn 0.4 V 0.6 Ni 0.85 Fe 0.15 alloy, the quantities of the zirconium and iron dissolved in the solution increase.The nickel-metal hydride ͑Ni-MH͒ batteries using hydrogen storage alloys as negative electrodes have been developed and commercialized because they provide a high energy density, high rate capability, and long cycle life without causing environmental pollution. 1-4 AB 2 -type Zr-based Laves phase metal hydrides have been attracting much attention recently because of their larger hydrogen storage capacity and relatively longer electrochemical charge/ discharge cycle life than the commercialized AB 5 -type alloys. 5-7 Nakano et al. 8 investigated the charge/discharge characteristics and the thermodynamic properties of Zr-based AB 2 -type alloys in which Ti or Nb substituted Zr and B site was substituted partially by Ni, V, Co, Cr, Cu, Fe, etc. Ovonic Battery Company ͑OBC͒ developed Zr-Ti-V-Ni AB 2 -type alloys with relatively large discharge capacity and excellent cycling performance. 9 Lee et al. 10 investigated the electrochemical charge/discharge characteristics of Zr 1Ϫx Ti x Mn 1Ϫy V y Ni 1Ϫz M z ͑M ϭ Al, Co, Fe͒ alloys. The alloys with x ϭ 0.4-0.6 showed better cycling performance than those with x Ͻ 0.4. Choi et al. 11 reported that the discharge capacity and the activation property of Ti 0.6 Zr 0.4 V 0.6 Mn 0.4 Ni 1.0 alloy were improved by varying the contents of V and Mn and its cycling performance was improved by substituting Cr for a part of V and Ni. Kim et al. 12 developed an AB 2 -type Zr-based Laves phase alloy with high discharge capacity and high rate capability.In our previous work, 13 we studied the electrochem...

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