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951.
DP Schenkein D Roitman KB Miller J Morelli E Stadtmauer AL Pecora P Cassileth H Fernandez BW Cooper L Kutteh HM Lazarus 《Canadian Metallurgical Quarterly》1997,3(4):210-216
The purpose of this study was to evaluate the safety and feasibility of front-line high-dose sequential (HDS) chemotherapy with peripheral blood stem cell (PBSC) transplantation in patients with newly diagnosed high-risk non-Hodgkin's lymphoma (NHL). Thirty-two patients with high-risk NHL (defined by the age-adjusted international index) underwent HDS chemotherapy followed by PBSC transplantation and consolidative radiotherapy. Twenty-eight patients (88%) had intermediate/high grade NHL and four patients (12%) had small noncleaved or lymphoblastic lymphoma. Twenty-four patients were classified as high-intermediate-risk (two risk factors) and eight patients were classified as high-risk (three risk factors). The five phases of HDS (see Fig. 1) consisted of Phase I (adriamycin, vincristine, and prednisone); Phase II (cyclophosphamide, filgrastim [G-CSF], and PBSC harvest); Phase III (methotrexate, leucovorin, vincristine; Phase IV (etoposide, filgrastim [G-CSF]); and Phase V (mitoxantrone, melphalan, autologous peripheral blood stem cell infusion, and filgrastim [G-CSF]). Radiation therapy was given to sites of previous bulk disease, 2400 cGy, (D + 30-100)]. Toxicity, engraftment, hospital utilization, overall survival, and relapse-free survival were evaluated. The high-dose sequential chemotherapeutic regimen was well tolerated. Treatment-related mortality was 6.25% with two deaths occurring secondary to sepsis and one death was caused by progressive disease. The major toxicity in Phase I-IV was grade 3 nausea/vomiting. The major toxicity in Phase V was grade 3 or 4 nausea/vomiting and mucositis. The median follow-up is 18.8 months (range 4-44 months). The overall survival (OS) and relapse-free survival (RFS) at 18 months for all patients were 78% (95% CI 37-90%) and 67% (95% CI 46-88%), respectively. The OS at 18 months for all patients, excluding the four patients with either small noncleaved or lymphoblastic lymphoma, was 82% (95% CI 65-98%) vs. 30% (95% CI 0-86%) (p = 0.0059). One patient in this latter group remains alive at 6 months follow-up. The RFS for all patients, excluding the four patients with either small noncleaved or lymphoblastic lymphoma, was 78% (95% CI 58-97%) vs. 0% (95% CI 0-0%) (p = 0.0004). High-dose sequential chemotherapy with initial PBSC transplantation is well tolerated and appears effective in high-risk NHL. Superior results were noted in patients with intermediate grade versus those with small noncleaved or lymphoblastic NHL. 相似文献
952.
AL Espinosa 《Canadian Metallurgical Quarterly》1998,49(1):97-104
Cardiovascular stress testing remains the mainstay of provocative evaluation for patients with known or suspected coronary artery disease. Stress echocardiography has become a valuable means of cardiovascular stress testing. It plays a crucial role in the initial detection of coronary disease, in determining prognosis, and in therapeutic decision making. The purpose of this document is to outline the recommended methodology for stress echocardiography with respect to personnel and equipment as well as the clinical use of this recently developed technique. Specific limitations will also be discussed. 相似文献
953.
Random mutagenesis with ouabain selection has been used to comprehensively scan the extracellular and transmembrane domains of the alpha1 subunit of the sheep Na+/K+-ATPase for amino acid residues that alter ouabain sensitivity. The four random mutant libraries used in this study include all of the transmembrane and extracellular regions of the molecule as well as 75% of the cytoplasmic domains. Through an extensive number of HeLa cell transfections of these libraries and subsequent ouabain selection, 24 ouabain-resistant clones have been identified. All previously described amino acids that confer ouabain resistance were identified, confirming the completeness of this random mutagenesis screen. The amino acid substitutions that confer the greatest ouabain resistance, such as Gln111-->Arg, Asp121-->Gly, Asp121-->Glu, Asn122-->Asp, and Thr797-->Ala were identified more than once in this study. This extensive survey of the extracellular and transmembrane regions of the Na+/K+-ATPase molecule has identified two new regions of the molecule that affect ouabain sensitivity: the H4 and the H10 transmembrane regions. The new substitutions identified in this study are Leu330-->Gln, Ala331-->Gly, Thr338-->Ala, and Thr338-->Asn in the H4 transmembrane domain and Phe982-->Ser in the H10 transmembrane domain. These substitutions confer modest increases in the concentration of cardiac glycoside needed to produce 50% inhibition of activity (IC50 values), 3.1-7.9-fold difference. The results of this extensive screening of the Na+/K+-ATPase alpha1 subunit to identify amino acids residues that are important in ouabain sensitivity further supports our hypothesis that the H1-H2 and H4-H8 regions represent the major binding sites for the cardiac glycoside class of drugs. 相似文献
954.
The low density lipoprotein receptor-related protein (LRP) is a large endocytic receptor that binds multiple ligands and is highly expressed in neurons. Several LRP ligands, including apolipoprotein E/lipoproteins and amyloid precursor protein, have been shown to participate either in Alzheimer's disease pathogenesis or pathology. However, factors that regulate LRP expression in neurons are unknown. In the current study, we analyzed the effects of nerve growth factor (NGF) treatment on LRP expression, distribution, and function within neurons in two neuronal cell lines. Our results show that NGF induces a rapid increase of cell surface LRP expression in a central nervous system-derived neuronal cell line, GT1-1 Trk, which was seen within 10 min and reached a maximum at about 1 h of NGF treatment. This increase of cell surface LRP expression is concomitant with an increase in the endocytic activity of LRP as measured via ligand uptake and degradation assays. We also found that the cytoplasmic tail of LRP is phosphorylated and that NGF rapidly increases the amount of phosphorylation. Furthermore, we detected a significant increase of LRP expression at the messenger RNA level following 24 h of NGF treatment. Both rapid and long term induction of LRP expression were also detected in peripheral nervous system-derived PC12 cells following NGF treatment. Taken together, our results demonstrate that NGF regulates LRP expression in neuronal cells. 相似文献
955.
S Moscarella G Buzzelli RG Romanelli M Monti C Giannini G Careccia EM Marrocchi AL Zignego 《Canadian Metallurgical Quarterly》1998,18(5):366-369
The prevalence of Helicobacter pylori (HP) IgG antibodies was analysed in a group of 142 asymptomatic children (group A) and in 31 pediatric patients (group B) with recurrent abdominal pain. HP IgG antibodies were measured by a commercially available fluorescence-enzyme immuno-assay test (Heloritest IgG, Fa Eurospital). In asymptomatic children the prevalence of HP IgG antibodies increased significantly with age from 17% with 6 years to more then 40% with 14 years. A higher prevalence of HP IgG antibodies was found in children living in more crowded housing conditions. Comparing the number of HP IgG positive children in group B (58%) to a matched population from group A (35%) no statistically different prevalence rates were found. Thus HP IgG antibodies are found in similar frequencies, in both, symptomatic and asymptomatic children. Therefore the presence of HP-IgG antibodies does not necessarily indicate that the HP infection is the cause for the recurrent abdominal pain in these children. 相似文献
956.
MH Maor LB North FF Cabanillas AL Ames MA Hess JD Cox 《Canadian Metallurgical Quarterly》1998,41(3):647-650
PURPOSE: To review the long-term clinical effects of unilateral kidney irradiation on overall renal function and blood pressure in patients with gastric lymphoma. METHODS AND MATERIALS: In the study were 27 patients with Stage I or II gastric lymphoma who had undergone irradiation of at least 24 Gy to > or = 1/3 of the left kidney. They include 16 women and 11 men, aged 31 to 77, with a mean age of 57.6 years (median 56). Fifteen patients had Stage I and 12 had Stage II disease. In 13 patients the whole kidney had been irradiated, and 14 had had partial kidney irradiation, at doses ranging between 24 and 40.5 Gy. All patients received combined chemotherapy with various drugs: all patients received corticosteroids, and five received cis-platinum. Their follow-up ranged between 0.7 and 7.8 years (mean 3.4 years). Data on possible effects of the treatment on blood pressure, renal function as assessed by blood urea and creatinine, and kidney shrinkage as seen by serial computed tomography scanning were collected on all patients. RESULTS: Three patients had persistent, mild elevations of urea and creatinine levels, which did not require special treatment. All three also received cis-platinum. Ipsilateral kidney shrinkage was evident in most patients. In 19 patients the craniocaudal measurement of the kidney shrank by > or = 1.6 cm. Shrinkage in other dimensions was also evident. The degree of atrophy was related to the volume of kidney irradiated. Only two patients developed hypertension, both at a low level of 150/90; one patient had had 40 Gy to the whole kidney, the other 40 Gy to half the kidney. Neither patient had elevated urea or creatinine. CONCLUSIONS: Notwithstanding the shrinkage to the irradiated part of the kidney, the treatment did not lead to clinically significant hypertension or renal dysfunction. The administration of cis-platinum to patients with gastric lymphoma that requires kidney irradiation should be further evaluated. 相似文献
957.
SR Simon TH Lee L Goldman AL McDonough SD Pearson 《Canadian Metallurgical Quarterly》1998,13(12):836-838
In many settings, primary care physicians have begun to delegate inpatient care to hospitalists, but the impact of this change on patients' hospital experience is unknown. To determine the effect on physician-patient communication of having the regular outpatient physician (continuity physician) continue involvement in hospital care, we surveyed 1,059 consecutive patients hospitalized with chest pain. Patients whose continuity physicians remained involved in their hospital care were less likely to report communication problems regarding tests (20% vs 31%, p =.03), activity after discharge (42% vs 51%, p =.02), and health habits (31% vs 38%, p =. 07). In a setting without a designated hospitalist system, communication problems were less frequent among patients whose continuity physicians were involved in their hospital care. New models of inpatient care delivery can maintain patient satisfaction but to do so must focus attention on improving physician-patient communication. 相似文献
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