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71.
Although interferon (IFN) has been used in elderly patients with acute lymphoblastic leukemia (ALL), the benefits from IFN therapy have not been properly assessed, especially as it was given combined with other cytotoxic drugs, which obscured the role of IFN if any. In 1997, we started a study aimed at improving our previous results in elderly patients with ALL and at assessing the therapeutic role of IFN in this disease. Fifty-eight patients with ALL, aged 55-81 years (median: 64.9 years), were randomly allocated to treatment with vindesine or vincristine during induction. After a first consolidation course, IFN was administered as a single agent for three months together with cranial radiotherapy. Chemotherapy was then resumed with a second consolidation course and maintenance. A complete remission (CR) was obtained in 58% of patients (CI: 45-71%), significantly less than in our previous study which included IFN combined with chemotherapy during maintenance (CR: 85%, CI:70-94%, p = 0.007). Overall survival (median: 289 vs 434 days in the previous study, p = 0.01) and disease-free survival (median: 146 vs 427 days, p = 0.009) were also inferior in the present study. In particular, the pattern of relapses over time suggested that the 3 month IFN treatment phase with no additional chemotherapy might have contributed to the comparatively poor outcome of this cohort. In addition, vindesine given during induction did not prove less neurotoxic than vincristine, did not improve the CR rate, and had no impact on survival. In conclusion, although similar to published studies in elderly patients with ALL, this study is inferior to our previous one. INF, given as a single drug, has a modest role if any in the treatment of older persons with ALL.  相似文献   
72.
73.
PURPOSE: We conducted a retrospective analysis to evaluate the safety and efficacy of Campath-1H, an anti-CD52 humanized monoclonal antibody, in previously treated T-prolymphocytic leukemia (T-PLL) patients in a compassionate-use program. PATIENTS AND METHODS: Seventy-six patients with T-PLL (including four chemotherapy-naive patients) received 3, 10, and 30 mg of Campath-1H on sequential days, followed by 30 mg three times weekly, as 2-hour intravenous infusions, for 4 to 12 weeks. RESULTS: Median patient age was 60 years (range, 35 to 84). Spleen liver, lymph node, and skin involvement were present in 64%, 40%, 54%, and 18% of patients, respectively. All tested patients had CD2, CD7, CD4, and/or CD8 positivity, whereas CD5 and CD3 were positive in 98% and 96% of tested patients, respectively. The objective response rate was 51% (95% confidence interval [CI], 40% to 63%), with a 39.5% complete response (CR) rate (95% CI, 28% to 51%). The median duration of CR was 8.7 months (range, 0.13+ to 44.4), and median time to progression was 4.5 months (range, 0.1 to 45.4) compared with 2.3 months (range, 0.2 to 28.1) after first-line chemotherapy. The median overall survival was 7.5 months (14.8 months for CR patients). The most common Campath-1H-related adverse events were acute reactions during or immediately after infusions. Fifteen infectious episodes occurred during treatment in 10 patients (13%), leading to treatment discontinuation in three. Eight patients experienced possibly related, late-onset infections. Severe thrombocytopenia and/or neutropenia occurred in six patients (8%), leading to treatment discontinuation in four. Two treatment-related deaths occurred. CONCLUSION: Campath-1H is an active drug in T-PLL patients for whom first-line therapy has failed. It has a favorable risk/benefit ratio and should be prospectively investigated in chemotherapy-naive patients.  相似文献   
74.
Weaver  DA; Hei  TK; Hukku  B; McRaven  JA; Willey  JC 《Carcinogenesis》1997,18(6):1251-1257
To establish a cell culture model for lung carcinogenesis, independent populations of the human papillomavirus 18-immortalized human bronchial epithelial cell line BEP2D were treated with high linear energy transfer radon-simulated alpha-particles, expanded and xenotransplanted into Nu/Nu mice. Six independent cell lines were established from tumors that developed from three separate radiation treatments as follows: treatment (Tx) 1 (30 cGy--two doses), H2BT, Tx 2 (30 cGy-- single dose), R30T1L, R30T2 and R30T3L, Tx 3 (30 cGy--single dose), H1ATN and H1ATBA1. Cytogenetic analysis revealed common changes in all tumor lines: loss of the Y chromosome (ch), one of three copies of ch8, one of three copies of ch14, and one of two copies of ch4p16-pter and ch11p15-pter. Analysis of polymerase chain reaction-amplified short tandem repeats of informative loci confirmed the loss of chY in all lines and loss of heterozygosity (LOH) at eight loci spanning the length of ch8 in all lines from Tx's 1 and 2. Our data support previous studies indicating the presence of tumor suppressor genes on ch8. LOH also was confirmed on ch14 at locus D14S306 in all cell lines from Tx 2 and in one of two lines from Tx 3. This region, 14q12-q13, may contain changes in one of the five known somatostatin receptor genes (SSTR1). No LOH was detected at any of the informative loci tested for on ch4 or ch11.   相似文献   
75.
Childhood tuberculosis is perceived by many as a disease of the past. Experience in a children's hospital serving a deprived population suggested that tuberculosis and other mycobacterial infections were not declining in clinical practice. Fifty three tuberculous and 11 atypical mycobacterial infections were identified between 1978 and 1992. There was no decline in tuberculosis and nine of the 11 atypical infections occurred in the last five years. Altogether 40% of cases of tuberculosis were in non-Asian children; 32% had arrived in the UK or visited family overseas in the previous year; and 38% had a history of tuberculosis contact, usually a close adult relative. Nationally, the previous decline in tuberculosis in all ages has reversed. In the local health districts in London's east end, childhood tuberculosis has also stopped declining and seems to be increasing. It is regrettable that BCG vaccination has been abolished by some districts in the UK, against current recommendations. Childhood tuberculosis is still common in the practice described here, including among children who do not fall into conventionally recognised high risk groups. Inner city dwellers and junior doctors are both highly mobile populations, adding to the risk that paediatricians, particularly those in training, may encounter tuberculosis with little or no previous experience of the condition.  相似文献   
76.
The interest of polyphenolics as therapeutic agents against diseases involving radical damage is growing. The phenolic contents of the hulls and flour from the seeds of Fagopyrum esculentum (French variety 'La Harpe') (total phenols, flavonoids, total flavanols, oligomeric proanthocyanidins) are compared with the antioxidative effects of the extracts against reactive oxygen species: hydrogen peroxide, hypochlorous acid, superoxide anion. The higher efficiency of the flour extract can be related to its higher flavanolic content rather than to flavonoids which are predominant in the hull extract.  相似文献   
77.
78.
Multisection, dual-echo magnetic resonance (MR) transaxial images of blood vessels contain both anatomic and qualitative information about flow. Even so, the images are produced as a series of two-dimensional tomographic sections from which full visualization of connected structures is difficult. A computer algorithm was developed that automatically detects flowing blood based on pixel intensity and calculated T2 and provides reconstructed views of vessels while analyzing and displaying flow characteristics. Images of abdominal vessels, aortic aneurysms, and the heart were encoded by flow and color to demonstrate depth. In addition, these data were reconstructed to derive a more accurate assessment of patency. With this technique, transaxial images can be used to analyze flow patterns, determine patent areas, and visualize all levels of vessels in a single image.  相似文献   
79.
Data on clinical features observed in patients with Waldenstrom's macroglobulinemia (WM) during follow-up remain limited. Therefore, we evaluated 860 follow-up procedures in 101 patients. Median age was 66 years and 5-year overall survival 72%, with a median follow-up of 36 months in surviving patients. Sixteen patients presented at diagnosis with two or three cytopenias lasting for at least 3 months (multiple cytopenias [MC]), and MC improved after treatment in eight patients, 4 to 18 months later. MC was observed during at least 6 consecutive months in 23 other patients, 2 to 73 months (median, 24) after diagnosis. MC occurred off-therapy in 12 patients, and on-therapy in 11. Regression occurred in three of the former patients, and in seven of the latter (6 to 24 months after completion of treatment; median, 7). Finally, the 4-year estimated cause-specific cumulative incidence was 40% in the 101 patients. A second malignancy was observed in 11 patients, histological transformation in three, and rapid rise of M-component in only six patients. In conclusion, the present analysis pointed out a high incidence of long lasting MC during the evolution of WM, and a low frequency of rapid rise of M component.  相似文献   
80.
OBJECTIVE: To determine whether children's food consumption is increased by the size of the group of children in which they are eating. DESIGN: Crossover study. SETTING: University based preschool. PARTICIPANTS: 54 children, aged 2.5-6.5 years. INTERVENTIONS: Each child ate a standardised snack in a group of three children, and in a group of nine children. MAIN OUTCOME MEASURES: Amount each individual child consumed, in grams. RESULTS: Amount eaten and snack duration were correlated (r = 0.71). The association between group size and amount eaten differed in the short (<11.4 min) versus the long (> or =11.4 min) snacks (p = 0.02 for the interaction between group size and snack duration). During short snacks, there was no effect of group size on amount eaten (16.7 (SD 11) g eaten in small groups vs 15.1 (6.6) g eaten in large groups, p = 0.42). During long snacks, large group size increased the amount eaten (34.5 (16) vs 26.5 (13.8), p = 0.02). The group size effect was partially explained by a shorter latency to begin eating, a faster eating rate and reduced social interaction in larger groups. CONCLUSIONS: Children consumed 30% more food when eating in a group of nine children than when eating in a group of three children during longer snacks. Social facilitation of food consumption operates in preschool-aged children. The group size effect merits consideration in creating eating behaviour interventions.  相似文献   
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