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991.
Myeloablative chemo-/radiotherapy supported by transplantation of autologous bone marrow or blood progenitor cells for acute leukemia, lymphoma, or myeloma continues to be associated with a high relapse rate because of the infusion of malignant stem cells and the lack of an in vivo graft-vs.-leukemia (GVL) effect. Although various methods of purging are established for marrow, purging procedures for blood progenitor cell preparations have not been widely used primarily because of the technical challenges to process a higher number of cells. As a broadly applicable method for immunological purging, we tested whether highly cytotoxic cells from a natural killer (NK) cell line characterized previously (NK-92) could be used for immunological purging of blood preparations. The NK-92 cell line, which was established from a patient with non-Hodgkin's lymphoma, can lyse in vitro a broad range of leukemia, lymphoma, and myeloma cell lines even at very low effector:target (E:T) ratios; this lysis is superior to cytotoxicity obtained from normal peripheral blood mononuclear cells (PBMCs) stimulated for 4 days with interleukin (IL)-2. In an attempt to quantitate the purging achievable with NK-92 cells, normal PBMCs were spiked with 10% K562 cells that had been transfected with the neo(r) marker gene (K562-neo(r). Various numbers of NK-92 cells were then added to the cell mixtures, which were incubated for 4 or 48 hours at 37 degrees C with or without IL-2 (500 U/mL). In order to prevent their proliferation, NK-92 cells were irradiated with 1000 cGy (cesium source). This radiation dose was determined to suppress proliferation of NK-92 cells, but at the same time maintain full cytotoxic activity. After co-culture, the cells were plated in methylcellulose containing 0.8 mg/mL G418. The number of surviving K562-neo(r) colonies was counted under the microscope 7 days later and the results were considered a quantitative readout for the purging efficacy of NK-92 cells. No neomycin-resistant K562 colonies could be detected up to a ratio of NK-92:K562-neo(r) cells of 5:1 (effective NK-92:PBMC ratio of 0.5:1). The presence or absence of IL-2 during the culture period did not affect the results. At this ratio of NK-92:PBMC, the growth of normal clonogenic hematopoietic progenitor cells was not compromised as determined by a standard methylcellulose assay. Considering that K562 is a rapidly proliferating cell line and that the input number of K562 cells (10%) tested here was high, the data suggest that the cytotoxic NK-92 clone (after irradiation to prevent proliferation) could be used effectively for immunological ex vivo purging without compromising hematopoietic cell function. 相似文献
992.
Adverse reactions to seafood are common and may cause many types of symptoms that are difficult to define. The nature of these reactions are variable including allergic and toxic reactions as well as infectious diseases. The differentiation between these entities is essential in choosing therapy. We describe 9 patients with IgE mediated allergic reactions due to crustaceans and fish diagnosed from case history, clinical findings, skin tests and specific IgE antibodies. Most symptoms of a IgE mediated allergic reaction appear within 30 minutes after ingestion. Characteristics clinical features may include an urticarial rash, gastrointestinal symptoms and even anaphylaxis. In this case immediate therapy with intravenous glucocorticoids, antihistamine and perhaps subcutaneous epinephrine is required. 相似文献
993.
M Brenner T Shankel NS Wang TA Waite H Wong A Hamilton Y Tadir T Milner J Boyajian E Chung B Tromberg AF Wilson MW Berns 《Canadian Metallurgical Quarterly》1996,153(3):1136-1140
Laser exposure of the pulmonary parenchyma during treatment of emphysema and other clinical indications causes acute lung injury. Animal investigations are needed to understand and control laser-induced lung injury. We hypothesized that lung injury is deeper from Nd:YAG laser exposures than CO2 exposures because of deeper penetration of Nd:YAG wavelength light. We compared the temporal evolution of histologic injury in rabbits resulting from continuous mode shallow CO2 and Nd:YAG laser pulmonary parenchymal exposures applied in rabbits. Forty-six New Zealand white (NZW) rabbits underwent treatment with CO2 laser (n=18), Nd:YAG laser (n=18), or sham thoracotomy control (n=10) to the visceral pleural surface using 1 min of exposure (5 watts, defocused to 70 W/cm2 power density for both lasers). Animals were killed at 0, 4, 7, 21, and 49 d after exposure. Lung injury, similar to that seen clinically in humans, developed in all laser-treated animals. Injury progressed from ischemia and vascular congestion, to edema and necrosis, followed by pleural and parenchymal fibrosis. The acute injury was qualitatively distinct and slightly deeper in CO2 than Nd:YAG-treated animals (p<0.02) despite the shallower depth of penetration of the CO2 laser. These findings may imply that higher absorption coefficient for CO2 laser energy results in greater focal temperatures and injury in the areas of direct exposure, and suggest that Nd:YAG laser exposure at these settings may cause shallower injury than CO2 lasers in humans undergoing clinical treatment. 相似文献
994.
C.Joseph Wong 《Computers & Structures》1984,19(3):315-320
A model that predicts the paper behavior during the printing process at various time intervals is proposed. The tendency of wrinkling can therefore be observed. This model will accommodate any paper topology induced by moisture effects or otherwise, and can analyze virtually any roll geometry and roll combinations.Nonlinear Finite Element Method is applied to the contact problem of two layered cylinders compressing a paper with arbitrary initial shape. The analysis assumed plane strain condition, the paper can therefore be treated as a beam. The result from the contact problem is applied to predict the behavior of the paper as it is feeding through the roll system. The Total Lagrange Formulation with Piola-Kirchoff Stress and Green-Lagrange strained is used. The quasi-static solution at different time intervals is presented. It was found that they agreed favorably with experiments. 相似文献
995.
Technology and device scaling considerations for CMOS imagers 总被引:9,自引:0,他引:9
Hon-Sum Wong 《Electron Devices, IEEE Transactions on》1996,43(12):2131-2142
This paper presents an analysis of the impact of device and technology scaling on active pixel CMOS image sensors. Using the SLA roadmap as a guideline, we calculate the device characteristics that are germane to the image sensing performance of CMOS imagers, and highlight the areas where the CIMOS imager technology may need to depart from “standard” CMOS technologies. The impact of scaling on those analog circuit performance that pertain to image sensing performances are analyzed. Our analyses suggest that while “standard” CMOS technologies may provide adequate imaging performance at the 2-1 μm generation without any process change, some modifications to the fabrication process and innovations of the pixel architecture are needed to enable CMOS to perform good quality imaging at the 0.5 μm technology generation and beyond. Finally, the challenges to the CMOS imager research community are outlined 相似文献
996.
When bone is fractured, a sequence of dynamic events ensue to restore form and therefore function. Many key biologic cell regulators for these events have been identified, expressed through recombinant technology, and their roles posited. Moreover, the availability of recombinantly engineered molecules, such as the bone morphogenetic proteins with their potential to benefit patient care, has ushered in an important era in clinical dentistry that may eliminate either autografting or bank bone allografts. Therefore, in this review article, we have highlighted some of the exciting biologic regulators relevant to bone fracture healing and outlined the dynamic elements in this process. 相似文献
997.
Lawson Katherine R.; Ruff Holly A.; McCarton-Daum Cecelia; Kurtzberg Diane; Vaughan Herbert G. Jr. 《Canadian Metallurgical Quarterly》1984,20(1):120
Compared older preterm and full-term infants in their response to objects in a dynamic multimodal context. In Study I, 67 12-wk-old full-term infants and 29 preterm infants (mean age 90 days) served as Ss. After familiarization with a silent moving object, full-term Ss recognized the object when it was stationary. When sound accompanied the moving object during familiarization, full-term Ss showed increased attention to the object but no subsequent recognition of that object. Neither high- nor low-risk preterms, at a comparable conceptional age, recognized the objects under any condition, but the low-risk preterms did show greater attention to the moving objects with sound. In Study II, 43 preterm Ss were tested approximately 6 mo after their estimated term date. The performance of the low-risk preterms was the same as that of full-terms; that is, through differential responding, they demonstrated association of an object and sound. In contrast, the high-risk preterms showed no differential looking. Thus both low- and high-risk preterms showed less differential responding than did normal full-terms at 3 mo, but at 6 mo only the high-risk preterms were different from the full-terms. Results suggest that the high-risk preterms are at a disadvantage for learning about the dynamic and multimodal aspects of their environment. (13 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
This paper is an assessment of three possible thermal-hydraulic high heat flux heat removal techniques which will result in adequate heat removal from fusion components with minimum penalty. The heat removal alternatives are: (1) subcooled flow boiling (SFB) with water, (2) high velocity helium gas convection (HGC), and (3) liquid metal (LM) heat transfer in the presence of a transverse magnetic field (TM). Advantages and disadvantages of each technique are delineated. Each heat removal technique is examined for a case study applicable to near-term fusion components such as limiters and divertors.Comparisons are made for the selected case study involving heat removal from a 1.5 m long, 1.0 cm diameter (inside) coolant channel which is subjected to a unifirm steady-state heat flux of 0.5 kW/cm2. The results show that SFB has the greatest heat removal capability, with the lowest coolant channel wall temperature and pumping power, followed by HGC and LMTM. Critical research and development needs for each technique are also summarized. 相似文献
999.
1000.
This study investigated relations between psychological health and problem-solving self-appraisal in 97 adults aged 65–96 years. Participants completed the Problem-Solving Inventory (P. P. Heppner, 1988) and two measures of psychological health encompassing both well-being and distress dimensions. Results of a canonical correlation analysis indicated that relations between problem-solving self-appraisal and psychological health were complex and sometimes contradictory. On the one hand, as problem-solving self-appraisal became more favorable (more confidence, more control, and increased approaching of problems), well-being increased and distress decreased. Conversely, perceptions of avoidant problem solving and decreased control were also associated with some increases in psychological health. Research and counseling implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献