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151.
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153.
Hong Chang John A. Blondal Sam Benchimol Mark D. Minden Hans A. Messner 《Leukemia & lymphoma》1995,19(1):165-171
Fourteen Non-Hodgkin's lymphoma cell lines were generated and assessed for the presence of structural pS3, c-myc and bcl-2 gene changes. Single or multiple changes were observed in II of the lines. Alterations of the p53 gene were most frequent and documented for 10 lines by immunoprecipition using the antibodies PAb 240 and PAb 1801. sequencing studies and Southern blot analysis. A detailed study was performed in one of the cell lines (XI-Ly 4) for which material of the original tumor sample was, available. Two point mutations identified by sequencing cDNA derived from the cell line were also present in the original tumor specimen. In contrast. DNA prepared from fibroblasts of the same patient did not show the mutations. Six of the 14 lines demonstrated c-myc rearrangements, while bcl-2 changes were observed in 4. The presence of c-myc was associated with shorter survival of this group of patients with aggressive disease. None of the other changes present as single or composite alterations were correlated with clinical outcome measures. 相似文献
154.
155.
This study describes the extent of cross-resistance and interactions for selected inhibitors of human cytomegalovirus (HCMV) DNA synthesis and DNA processing. HCMV isolates resistant to the benzimidazole D-ribonucleoside viral DNA processing inhibitors TCRB and BDCRB were sensitive to BAY 38-4766, a non-nucleoside inhibitor of viral DNA processing. This indicates that these two drug types have distinct interactions with the products of HCMV genes UL56 and UL89 required for viral DNA cleavage and packaging. These virus isolates also were sensitive to ganciclovir (GCV) but slightly resistant to the L-benzimidazole ribonucleoside viral DNA synthesis inhibitor 1263W94. Virus resistant to 1263W94 remained sensitive to BDCRB, GCV, and BAY 38-4766. Examination of drug-drug interactions in cell culture assays measuring inhibition of HCMV replication revealed strong synergism for the combination of BDCRB with 1263W94, and for combinations of 1263W94 with cidofovir (CDV) and foscarnet (PFA), but not with GCV. Combinations of GCV with CDV and PFA were synergistic as well. The combination of GCV with 1263W94 showed additive antiviral interactions, whereas, a combination of BAY 38-4766 with GCV showed antagonism. Interaction of BDCRB with BAY 38-4766 showed a mixed pattern of synergy and antagonism. The antiviral synergy observed between GCV and PFA or CDV serves to validate clinical combination therapies for these drugs. Antagonism seen for BAY 38-4766 with GCV indicates that these two drugs are unlikely to be useful for combination therapies. Notably, 1263W94 demonstrated greater synergy in combination with PFA or CDV than did GCV, suggesting some promise for this benzimidazole L-riboside in such combination therapies. 相似文献
156.
Bastasch M Panella TJ Kretzschmer SL Graham D Mayo M Williamson S 《Investigational new drugs》2002,20(3):339-342
Background: More active agents areneeded in the treatment of metastaticnon-small cell lung cancer. Pyrazoloacridine (PZA) is a 9-methoxyacridine compound containing a reducible5-nitro substituent. Although themechanism of action of PZA is unknown, theacridine compounds are known to causecytotoxicity by interaction with DNA andRNA.
Methods: Eighteen patients withmetastatic non-small cell lung carcinomawere treated with pyrazoloacridine.Pyrazoloacridine was administered as athree-hour infusion at 750 mg/M2 every21 days.
Results: There were no objectiveresponses. One patient maintained stabledisease for 20 months. Median survival was4.8 months. The primary toxicity wasgranulocytopenia with 5 patientsexperiencing severe infections.
Conclusions: Pyrazoloacridine has nodemonstrable activity in patients withmetastatic non-small cell carcinoma of thelung when given at this dose andschedule. 相似文献
157.
What determines the use of home care services by elderly people? 总被引:3,自引:0,他引:3
The objective of the present study was to investigate the determinants of use of statutory and private home care services by older people living in the community. A questionnaire was distributed to a stratified random sample of 2,000 elderly people living in the community registered with 11 general practices in a British city (equal numbers of men and women, aged 65-74 years, and 75 years or over). The outcome measures were the use of statutory or private home care services in the previous 3 months. Logistic regression was used to explore potential determinants of the use of these services. The response rate was 79%. Increasing age, not owning a car and being a widow(er) were associated with greater use of both statutory and private home care services, as was worse self-reported overall health. Worse physical functioning, worse emotional health, problems with cognition, foot problems and a greater number of falls were determinants of use of statutory and private services. Older age on leaving full-time education was associated with increased use of private home care services. Problems with eyesight were determinants for both types of home care services for women, but only private services for men. For women, leakage of urine was associated with greater use of private services. Social networks and social support were not generally associated with use of these services after controlling for demographic factors. Understanding the determinants for the use of both statutory and private home care services is important because of the increasing numbers of elderly people in the population and the policy to maintain older people in their own homes. Purchasers and providers should be able to address at least some of the modifiable predictors. 相似文献
158.
Puoane T Steyn K Bradshaw D Laubscher R Fourie J Lambert V Mbananga N 《Obesity research》2002,10(10):1038-1048
OBJECTIVES: To ascertain the anthropometric profile and determinants of obesity in South Africans who participated in the Demographic and Health Survey in 1998. RESEARCH METHODS AND PROCEDURES: A sample of 13,089 men and women (age, > or =15 years) were randomly selected and then stratified by province and urban and nonurban areas. Height, weight, mid-upper arm circumference, and waist and hip circumference were measured. Body mass index (BMI) was used as an indicator of obesity, and the waist/hip ratio (WHR) was used as an indicator of abdominal obesity. Multivariate regression identified sociodemographic predictors of BMI and waist circumference in the data. RESULTS: Mean BMI values for men and women were 22.9 kg/m(2) and 27.1 kg/m(2), respectively. For men, 29.2% were overweight or obese (> or =25 kg/m(2)) and 9.2% had abdominal obesity (WHR > or =1.0), whereas 56.6% of women were overweight or obese and 42% had abdominal obesity (WHR >0.85). Underweight (BMI <18.5 kg/m(2)) was found in 12.2% of men and 5.6% of women. For men, 19% of the variation of BMI and 34% of the variation in waist circumference could be explained by age, level of education, population group, and area of residence. For women, these variables explained 16% of the variation of BMI and 24% of the variation in waist circumference. Obesity increased with age, and higher levels of obesity were found in urban African women. DISCUSSION: Overnutrition is prevalent among adult South Africans, particularly women. Determinants of overnutrition include age, level of education, ethnicity, and area of residence. 相似文献
159.
A discrete event simulation models the progress of patients who have had a coronary event, through their treatment pathways and subsequent coronary events. The main risk factors in the model are age, sex, history of previous events and the extent of the coronary vessel disease. The model parameters are based on data collected from epidemiological studies of incidence and prognosis, efficacy studies, national surveys and treatment audits. The simulation results were validated against different sources of data. The initial results show that increasing revascularisation has considerable implications for resource use but has little impact on patient mortality. 相似文献
160.
Comparison of the expression of calcitonin receptor-like receptor (CRLR) and receptor activity modifying proteins (RAMPs) with CGRP and adrenomedullin binding in cell lines
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Choksi T Hay DL Legon S Poyner DR Hagner S Bloom SR Smith DM 《British journal of pharmacology》2002,136(5):784-792
1. The calcitonin receptor-like receptor (CRLR) and specific receptor activity modifying proteins (RAMPs) together form receptors for calcitonin gene-related peptide (CGRP) and/or adrenomedullin in transfected cells. 2. There is less evidence that innate CGRP and adrenomedullin receptors are formed by CRLR/RAMP combinations. We therefore examined whether CGRP and/or adrenomedullin binding correlated with CRLR and RAMP mRNA expression in human and rat cell lines known to express these receptors. Specific human or rat CRLR antibodies were used to examine the presence of CRLR in these cells. 3. We confirmed CGRP subtype 1 receptor (CGRP(1)) pharmacology in SK-N-MC neuroblastoma cells. L6 myoblast cells expressed both CGRP(1) and adrenomedullin receptors whereas Rat-2 fibroblasts expressed only adrenomedullin receptors. In contrast we could not confirm CGRP(2) receptor pharmacology for Col-29 colonic epithelial cells, which, instead were CGRP(1)-like in this study. 4. L6, SK-N-MC and Col-29 cells expressed mRNA for RAMP1 and RAMP2 but Rat-2 fibroblasts had only RAMP2. No cell line had detectable RAMP3 mRNA. 5. SK-N-MC, Col-29 and Rat-2 fibroblast cells expressed CRLR mRNA. By contrast, CRLR mRNA was undetectable by Northern analysis in one source of L6 cells. Conversely, a different source of L6 cells had mRNA for CRLR. All of the cell lines expressed CRLR protein. Thus, circumstances where CRLR mRNA is apparently absent by Northern analysis do not exclude the presence of this receptor. 6. These data strongly support CRLR, together with appropriate RAMPs as binding sites for CGRP and adrenomedullin in cultured cells. 相似文献