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Summary Malignant lymphomas can be subdivided into Hodgkin's disease and low- or high-grade non-Hodgkin's lymphoma (NHL). The principal therapeutic options are polychemotherapy and radiotherapy. Besides the histological classification, staging of the disease with particular regard to risk factors is an essential prerequisite for the therapeutic decision. Diagnostic imaging modalities such as computer tomography, magnetic resonance imaging, and ultrasonography have improved the accuracy of clinical staging such that invasive pathological staging is only necessary in exceptional cases. A novel therapeutic approach is high-dose chemotherapy with autologous haematopoietic stem-cell support. This treatment improves the survival of patients with relapsed high-grade NHL. The place of high-dose therapy as the primary therapeutic option in malignant lymphoma is now being assessed in prospective studies following encouraging results from single-centre studies, including those involving the treatment of low-grade lymphoma. The effects of antibodies directed against lymphatic cells are currently being examined in experimental treatments. An assessment of the viability and rate of proliferation of lymphoma tissue on completion of therapy using sensitive radiological and nuclear medical methods is an important aim for the future. Eingegangen am 5. November 1996 Angenommen am 12. November 1996  相似文献   
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OBJECTIVE: This study examined the health status and hospital use of women after the birth of a premature, low-birthweight infant. METHODS: The subjects were women with infants who participated in a multisite, randomized trial of an early intervention program. The outcomes examined were (1) a maternal health rating of poor or fair (i.e., poorer health) 5 years following delivery and (2) hospital use for a non-pregnancy-related condition. RESULTS: By the fifth year after delivery, 29.7% of the women had been hospitalized for a non-pregnancy-related condition. Women who reported poorer health status (adjusted relative risk [RR] = 2.39; 95% confidence interval [CI] = 1.86, 3.07) or who had asthma (RR = 2.24; CI = 1.31, 3.80) were at greatest risk. After 5 years, 16.9% of the women said they were in poorer health. The number of intervening years in poorer health (1 year, RR = 3.17; CI = 2.04, 4.94; > 1 year, RR = 8.42; CI = 2.20, 12.88), more than 1 year of poverty (RR = 3.28; CI = 1.90, 5.66), obesity (RR = 3.30; CI = 1.44, 7.55), and more than 1 year of employment (RR = 0.55; CI = 0.36, 0.86) were all significantly associated with poorer health. CONCLUSIONS: The continued, substantial morbidity and hospital use of women with a premature, low-birthweight infant has not previously been reported. This observation needs to be verified.  相似文献   
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Midazolam is increasingly being used for oral sedation in pediatric dentistry. Unfortunately, it is available only as a parenteral formulation in Canada and the United States. Preparation of the parenteral solution for oral use is not uniform and leads the clinician to question the stability of this drug when used in conjunction with these vehicles. Therefore, the purpose of this study was to investigate the chemical stability of parenteral midazolam as an oral formulation to determine its expiry date. This was evaluated using a validated stability-indicating liquid chromatographic method. Midazolam was diluted in orange-flavored syrup to yield concentrations of 0.35, 0.64, and 1.03 mg/ml and then stored at room temperature. Samples were drawn on each of 9 study days (0, 1, 2, 6, 7, 9, 13, 21, and 102) and chromatographed. On each study day, solutions were inspected visually for changes in color, clarity, and appearance of particulate matter. Midazolam concentrations were considered within acceptable limits if they were not less than 90% of the initial concentration. Over the 102-day study period, there was no significant change in concentration in any of the solutions. On day 102, the remaining midazolam was within 7% of the day zero concentration. Therefore, these formulations of midazolam are stable at room temperature for a period of 102 days and would be suitable for clinical use.  相似文献   
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BACKGROUND. Endothelin is a family of potent vasoconstrictor peptides of vascular endothelial origin. Although it has been proposed that the vasoconstrictor effects of endothelin are produced at the local vascular level, increased plasma concentration of endothelin has been identified in cardiovascular disorders. METHODS AND RESULTS. We tested whether immunoreactive endothelin-1 could be detected by radioimmunoassay in plasma of congestive heart failure patients and whether levels correlated with hemodynamic characteristics. Twenty congestive heart failure patients (New York Heart Association class II-IV) were sampled in the morning after an overnight fast, before medication. Cardiac index was decreased to 2.14 +/- 0.45 l/m/m2, and pulmonary wedge pressure was increased to 22 +/- 7 mm Hg. The ranges of pulmonary pressures were: systolic, 22-100 mm Hg, mean, 13-61 mm Hg, and diastolic, 8-42 mm Hg. The endothelin-1 level was 9.07 +/- 4.13 pg/ml (range, 4-19 pg/ml), which was increased compared with 12 normals (3.7 +/- 0.6 pg/ml; range, 2.8-4.7 pg/ml); the difference was statistically significant (p less than 0.0001). Endothelin-1 significantly correlated with pulmonary pressures (systolic, r = 0.78; mean, r = 0.80; diastolic, r = 0.77; all p less than 0.003) and pulmonary vascular resistance (r = 0.65, p less than 0.01). Endothelin-1 strongly correlated with the resistance ratio (pulmonary vascular resistance/systemic vascular resistance) (r = 0.88, p less than 0.0001). Stepwise multiple regression analysis confirmed the significance of these observations. CONCLUSIONS. Elevated immunoreactive endothelin-1 specifically correlated with the extent of pulmonary hypertension in congestive heart failure patients. Whether endothelin-1 is a regional mediator of pulmonary hypertension or a marker for its occurrence requires additional evaluation.  相似文献   
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Suppression of acute lymphoblastic leukemia by the human wild-type p53 gene.   总被引:11,自引:0,他引:11  
Independent mutations in both alleles of the p53 tumor suppressor gene are a frequent finding in human T-cell acute lymphoblastic leukemia (T-ALL) cell lines and in the cells of some T-ALL patients in relapse. One major goal of studying the status of p53 (and other tumor suppressor genes) in human cancer is to facilitate the suppression of the tumorigenic phenotype through the restoration of the expression of the wild-type allele. While the efficient insertion of a suppressor into all cells of solid/metastatic human tumors may at present be impossible, insertion into leukemia cells may be feasible due to the accessibility of the leukemia cells in the body. To examine the feasibility of suppressing the tumorigenicity of human T-leukemia cells, the human T-ALL cell line Be-13, which lacks endogenous p53 protein, was infected with a recombinant retrovirus encoding the wild-type allele of human p53 (hwtp53). Expression of p53 reduced the growth rate of infected Be-13 cells in vitro, suppressed colony formation in methylcellulose cultures, and abrogated their tumorigenic phenotype in nude mice in vivo. These results suggest that suppression of the leukemic phenotype of relapse T-ALL-derived Be-13 cells is feasible. Acute leukemia cell suppression via high-efficiency infection with retroviruses encoding wtp53 may be feasible and beneficial in T-ALL cases as part of a bone marrow transplantation regimen in an effort to reduce the frequency of posttransplantation relapse.  相似文献   
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