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11.
Background
The objective of this study was to demonstrate the use of an association rule mining approach to discover associations between selected socioeconomic variables and the four most leading causes of cancer mortality in the United States. An association rule mining algorithm was applied to extract associations between the 1988–1992 cancer mortality rates for colorectal, lung, breast, and prostate cancers defined at the Health Service Area level and selected socioeconomic variables from the 1990 United States census. Geographic information system technology was used to integrate these data which were defined at different spatial resolutions, and to visualize and analyze the results from the association rule mining process. 相似文献12.
Perkins SN; Hursting SD; Haines DC; James SJ; Miller BJ; Phang JM 《Carcinogenesis》1997,18(5):989-994
Transgenic mice with both alleles of the p53 tumor suppressor gene product
'knocked out' by gene targeting are susceptible to early development of
tumors, chiefly lymphomas and sarcomas. Compared with the control group,
administration of dehydroepiandrosterone (DHEA) at 0.3% of the diet to male
p53-deficient mice extended their lifespan by delaying death due to
neoplasms (from 105 to 166 days on study, P = 0.002), primarily by
suppressing lymphoblastic lymphoma (from 45 to 6% of neoplastic deaths, P =
0.010). Treatment with a synthetic DHEA analog,
16alpha-fluoro-5-androsten-17-one (compound 8354), at 0.15% of the diet
also increased lifespan, to 140 days for mice that developed tumors (P =
0.037). The effects of these steroids on lifespan and tumor development did
not appear to be strongly related to inhibition of food consumption and
weight gain, in that a group pair-fed with control diet to the reduced food
consumption of the DHEA-treated group developed and died of the same types
of neoplasms at the same rate as the controls fed ad libitum. The
chemopreventive effect of these steroids has been proposed to be due to
suppression of DNA synthesis by inhibition of glucose 6-phosphate
dehydrogenase, the rate-limiting enzyme of the pentose phosphate pathway.
Although DHEA and its analog are strong non- competitive inhibitors of this
enzyme in vitro, treatment with DHEA did not deplete cellular nucleotide
pools in the liver, as would have been predicted. The chemopreventive
effect of DHEA in this model may be due to steroid-induced thymic atrophy
and suppression of T cell lymphoma, permitting these mice to survive long
enough to develop tumors with longer latency.
相似文献
13.
AM VOGEL D LENNON SN AMERATUNGA J HOLYOAKE 《Journal of paediatrics and child health》1996,32(6):484-490
Objective : To establish the prevalence of specific chronic conditions of childhood in the Auckland area and to quantify resource use by these children.
Methodology : Estimates were made from available registry data and published data sources of the population of children with selected chronic conditions resident in the Auckland Area Health Board area. Resource use data were extracted for admissions to Auckland public hospitals and from providers of community based technology services.
Results : The largest community prevalence groups are those with asthma, intellectual handicap, congenital heart disease and epilepsy. Children aged 0-14 with chronic conditions accounted for at least 14340 hospital days stay in Auckland in 1992 at an estimated minimum cost of $7.9 million. Over 200 children are dependent on technological aids at home.
Conclusions : There are sparse data on the numbers and needs of children with chronic conditions in the population. A non-categorical approach which crosses disease entities may be the best method of meeting common needs. 相似文献
Methodology : Estimates were made from available registry data and published data sources of the population of children with selected chronic conditions resident in the Auckland Area Health Board area. Resource use data were extracted for admissions to Auckland public hospitals and from providers of community based technology services.
Results : The largest community prevalence groups are those with asthma, intellectual handicap, congenital heart disease and epilepsy. Children aged 0-14 with chronic conditions accounted for at least 14340 hospital days stay in Auckland in 1992 at an estimated minimum cost of $7.9 million. Over 200 children are dependent on technological aids at home.
Conclusions : There are sparse data on the numbers and needs of children with chronic conditions in the population. A non-categorical approach which crosses disease entities may be the best method of meeting common needs. 相似文献
14.
O'Day SJ; Rabinowe SN; Neuberg D; Freedman AS; Soiffer RJ; Spector NA; Robertson MJ; Anderson K; Whelan M; Pesek K 《Blood》1994,83(9):2707-2714
Recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) clearly hastens myeloid recovery in patients with relapsed hematologic malignancies undergoing autologous bone marrow transplantation (ABMT). In efforts to further improve neutrophil engraftment and shorten hospital stay in ABMT patients, rhGM-CSF was administered by a potentially more potent route (continuous infusion) to non-Hodgkin's lymphoma (NHL) patients with better BM reserve (first remission). Time to myeloid engraftment was compared with that of NHL patients treated in first remission at our institution on a similar ABMT protocol but without growth factor support (controls). Median neutrophil engraftment (absolute neutrophil count, 500 cells/microL) in first remission patients treated with rhGM-CSF was 14 days, compared with 22 days in controls (P = .0001). Hospital stays were also significantly reduced for rhGM-CSF patients (P = .0003). Platelet engraftment did not differ between the two groups. Persistent fever and generalized serositis were the primary toxicities. rhGM-CSF, delivered by this route, was efficacious but more toxic than 2-hour rhGM-CSF infusions previously reported by other investigators. Future alterations in both dose and schedule may retain comparable efficacy yet diminish toxicity. 相似文献
15.
S Thavagnanam SN Christie GM Doherty PV Coyle MD Shields LG Heaney 《Acta paediatrica (Oslo, Norway : 1992)》2010,99(3):394-398
Aim: The aim of this study was to determine if asthmatic children have viruses more commonly detected in lower airways during asymptomatic periods than normal children. Methods: Fifty‐five asymptomatic children attending elective surgical procedures (14 with stable asthma, 41 normal controls) underwent non‐bronchoscopic bronchoalveolar lavage. Differential cell count and PCR for 13 common viruses were performed. Results: Nineteen (35%) children were positive for at least one virus, with adenovirus being most common. No differences in the proportion of viruses detected were seen between asthmatic and normal ‘control’ children. Viruses other than adenovirus were associated with higher neutrophil counts, suggesting that they caused an inflammatory response in both asthmatics and controls (median BAL neutrophil count, 6.9% for virus detected vs. 1.5% for virus not detected, p = 0.03). Conclusions: Over one‐third of asymptomatic children have a detectable virus (most commonly adenovirus) in the lower airway; however, this was not more common in asthmatics. Viruses other than adenovirus were associated with elevated neutrophils suggesting that viral infection can be present during relatively asymptomatic periods in asthmatic children. 相似文献
16.
17.
K-Ⅱ系k阿片激动剂U-50488的同类物。通过部分离体和整体实验比较了K-Ⅱ与U-50488的药理作用。实验发现,K-Ⅱ抑制电刺激兔输精管收缩的IC50值为0.42 nmol/L,U-50488为26.5 nmol/L;K-Ⅱ抑制小鼠运动功能(横筛法)的ED50值为1.7 mg/g,U-50488为15.3 mg/kg;K-Ⅱ的小鼠LD50值为152.5 mg/kg,U-50488为118.4 mg/g;K-Ⅱ明显降低小鼠自发活动的作用比U-50488强5倍。结果表明,K-Ⅱ是一个药理作用较U-50488强的k受体激动剂。 相似文献
18.
This randomised, double-blind study conducted at nine sites in the UK and the Netherlands compared the safety and antidepressant efficacy of venlafaxine and dothiepin. Ninety-two geriatric patients (aged 64-87 years) with major depression were randomly assigned to receive either venlafaxine or dothiepin for up to 43 days. The dose of venlafaxine or dothiepin was titrated up to a maximum of 150 mg per day for the first 15 days, and thereafter could range from 50 to 150 mg per day. Adjusted mean scores on the MADRS and the HAM-D decreased significantly (p 0.05) from baseline to the end of the study in both groups. A response to therapy was observed in 60% of patients in the venlafaxine group and 53% of patients in the dothiepin group on the MADRS, and in 60% of patients in both groups on the HAM-D. Suicidal ideation scores on the MADRS were significantly (p=0.042) lower in the venlafaxine group at week 6. Treatment-emergent study events were the primary reason for withdrawal in only 7% of venlafaxine-treated patients and 8% of dothiepin-treated patients. The results confirm the efficacy and tolerability of venlafaxine for treating major depression in the elderly. 相似文献
19.
Infusible platelet membrane microvesicles: a potential transfusion substitute for platelets 总被引:8,自引:0,他引:8
FC Chao ; BK Kim ; AM Houranieh ; FH Liang ; MW Konrad ; SN Swisher ; JL Tullis 《Transfusion》1996,36(6):536-542
BACKGROUND: Several substitutes for intact, viable platelets have been used for transfusion, both to people and in animal models, with varied success. Infusible platelet membrane (IPM) is prepared from human platelets. IPM retains the glycoprotein (GP)lb receptor and has platelet factor 3 activity (procoagulant activity). However, factor V, serotonin, a cytoplasmic marker enzyme (purine nucleotide phosphorylase), GPIIb/IIIa complex, and HLA class I and II antigens are all absent in IPM. STUDY DESIGN AND METHODS: IPM is prepared from outdated platelets. The platelets were disrupted by freezing and thawing; they were washed and heated to inactivate possible viral contaminants, and then the sonicated membrane microvesicle fraction was separated and lyophilized. The hemostatic activity of IPM was measured by its ability to reduce the prolonged bleeding time in thrombocytopenic rabbits. RESULTS: Administration of IPM at a dose of 2 mg per kg results in a substantial reduction in the bleeding time. In a series of 23 experiments, a median preinjection bleeding time of 15 minutes was reduced to 6 minutes within 4 hours after IPM administration. Administration of IPM did show a mild enhancement in the thrombogenicity index, as measured in the Wessler rabbit model. This enhancement is, however, not significant, as a thrombogenicity index value of up to 0.6 is clinically acceptable. CONCLUSION: IPM may have clinical potential as a substitute for platelets in the treatment of bleeding due to thrombocytopenia. 相似文献
20.
We reviewed the literature data on the cellular and molecular mechanisms of postischemic epileptogenesis, which is modeled in a culture of dissociated neurons and organotypic culture of nervous tissue. We summarized the data on the involvement of glutamate excitotoxicity in the development of epileptiform discharges generated by neurons in culture after glutamate application and on the involvement of neuronal calcium overload in the formation of seizure activity. We also presented data on the effects of neuroprotectors in models of postischemic epileptogenesis in vitro. 相似文献