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61.
Survival variability by race and ethnicity in childhood acute lymphoblastic leukemia 总被引:4,自引:0,他引:4
Context The role of race/ethnicity in survival of children with acute lymphoblastic leukemia (ALL) is unclear, with some studies reporting poorer survival among minority children and others reporting equivalent survival across race/ethnicity in the modern, risk-stratified treatment era. Objective To investigate the relation between race/ethnicity and survival in a large, population-based analysis of incident ALL cases in the United States. Design, Population, and Setting This study included 4952 individuals diagnosed with ALL between 1973 and 1999 at age 19 years or younger. ALL cases were identified from 9 population-based registries of the National Cancer Institute's Surveillance, Epidemiology, and End Results program. Main Outcome Measures Survival probabilities were compared among white, black, Hispanic, Asian/Pacific Islander, and American Indian/Alaskan Native children. Kaplan-Meier curves and proportional hazard ratios from Cox regression analysis were calculated, accounting for treatment era (1973-1982, 1983-1989, and 1990-1999), age at diagnosis (<1, 1-9, and 10-19 years), and sex. Results Although overall 5-year survival probabilities improved with each successive treatment era, differences according to race/ethnicity persisted. For 1990-1999, 5-year survival was 84% for white children, 81% for Asian/Pacific Islander children, 75% for black children, and 72% for both American Indian/Alaskan Native children and Hispanic children. The largest difference by race/ethnicity was observed among children diagnosed between ages 1 and 9 years. Compared with white children, after adjusting for treatment era, age at diagnosis, and sex, children of black, Hispanic, and American Indian/Alaskan Native descent had hazard ratios of 1.50 (95% CI, 1.0-2.2; P = .03), 1.83 (95% CI, 1.4-2.4; P<.001), and 1.90 (95% CI, 0.8-4.6; P = .16). Conclusions Black, Hispanic, and American Indian/Alaskan Native children with ALL have worse survival than white and Asian/Pacific Islander children, even in the contemporary treatment era. Future work must delineate the social and biological factors, including any differences in pharmacokinetics associated with chemotherapeutic agents, that account for disparities in outcome. 相似文献
62.
1. The directly acting vasodilator hydralazine has been proposed to act at an intracellular site in vascular smooth muscle to inhibit Ca(2+) release. 2. This study investigated the mechanism of action of hydralazine on rabbit aorta and pulmonary artery by comparing its effects on the tension generated by intact and beta-escin permeabilized vessels and on the cytoplasmic Ca(2+) concentration, membrane potential and K(+) currents of isolated vascular smooth muscle cells. 3. Hydralazine relaxed pulmonary artery and aorta with similar potency. It was equally effective at inhibiting phasic and tonic contractions evoked by phenylephrine in intact vessels and contractions evoked by inositol 1,4,5 trisphosphate (IP(3)) in permeabilized vessels. 4. Hydralazine inhibited the contraction of permeabilized vessels and the increase in smooth muscle cell Ca(2+) concentration evoked by caffeine with similar concentration dependence, but with lower potency than its effect on IP(3) contractions. 5. Hydralazine had no effect on the relationship between Ca(2+) concentration and force generation in permeabilized vessels, but it slowed the rate at which maximal force was developed before, but not after, destroying sarcoplasmic reticulum function with the calcium ionophore, ionomycin. 6. Hydralazine had no effect on membrane potential or the amplitudes of K(+) currents recorded from isolated smooth muscle cells over the concentration range causing relaxation of intact vessels. 7. The results suggest that the main action of hydralazine is to inhibit the IP(3)-induced release of Ca(2+) from the sarcoplasmic reticulum in vascular smooth muscle cells. 相似文献
63.
Reports that central nervous system (CNS) cancer rates are increasing have prompted debate on whether secular trends reflect environmental changes related to etiology or artifacts of case ascertainment. We present the most recent data from the National Cancer Institute's Surveillance, Epidemiology, and End Results program on incidence rates and trends of CNS malignancies, including primary CNS lymphomas, and on survival probability. We discuss the new 2000 standard for adjusting rates; underreporting of CNS tumor rates resulting from the exclusion of nonmalignancies in most cancer registries; and information on CNS tumor risk factors, including concerns related to nonionizing electromagnetic fields and wireless mobile telephones. 相似文献
64.
产后出血的预防和处理指南 总被引:3,自引:0,他引:3
目的:为产后出血(PPH)的预防和临床处理作一综述,为临床医师提供预防和处理产后出血的指南。涉及方面:预防、适当干预、使其影响最小化的方法。结果:建立常规,便于临床医师鉴别可能的高危人群,一旦发生产后过多出血,可指导临床如何迅速处理。证据:遵循加拿大定期健康检查办公室制定的证据等级。评估:由产科专家完善。利弊和成本:评估子宫收缩药和其他积极处理措施的方便性、正确性、有效性和安全性。建议:根据证据的等级,本指南分等级列出了12条建议。确认:按照MeSH词表推荐的postpartum haemorrhage在medline上查询相关文献,在Cochrane图书馆查找相关研究文献,并参考the ALARMcourse Manual。发起人:由产科临床实践委员会制定和综述,并由SOGC(加拿大妇产科协会)委员会批准。 相似文献
65.
Electrophysiological recording methods used in vascular biology 总被引:5,自引:0,他引:5
Gurney AM 《Journal of pharmacological and toxicological methods》2000,44(2):409-420
Vascular tone can be regulated by drugs that alter the activities of membrane ionic channels located in endothelial or smooth muscle cells in the vascular wall. This review examines the methods that are available to investigate the activities and pharmacological modulation of ion channels in vascular cells. They range from classical sucrose-gap and sharp-microelectrode techniques for studies of intact vessels, to the now widely used patch-clamp techniques for voltage-clamp recording of single-channel and macroscopic currents in isolated cells. Each method is described, along with examples of applications and discussion of potential problems and limitations. 相似文献
66.
67.
W. J. Graham Director V. Hundley Research Sister A. L. McCheyne Research Midwife M. H. Hall Consultant bstetrician/Gynaecologist E. Gurney Medical Statistician J. Milne Nurse Manager 《BJOG : an international journal of obstetrics and gynaecology》1999,106(3):213-220
Objective To assess the degree and nature of women's involvement in the decision to deliver by caesarean section, and women's satisfaction with this involvement.
Design Observational study.
Setting The maternity unit in a large teaching hospital.
Sample One hundred and sixty-six women undergoing caesarean section.
Methods Interviews with the women on the third or fourth day postpartum, questionnaires sent to the women at 6 weeks and at 12 weeks postpartum, and extraction of information from the women's medical records.
Main outcome measures Women's knowledge, satisfaction, and involvement in making the decision concerning their caesarean section.
Results The majority of the women were satisfied with the information they received during pregnancy on caesarean section and with their involvement in making the decision, but the proportions were significantly higher for elective than emergency sections. For 7% of the women, maternal preference for caesarean section was a direct factor in making the decision. Just over half of the 166 women reported that they were not debriefed on the reasons for their caesarean section before their discharge from hospital. Almost a third of the women undergoing emergency caesarean section expressed negative feelings towards their delivery, compared with 13% of those undergoing elective caesarean sections.
Conclusion Women are not a homogeneous group in terms of their requirements for information, nor their desire to be involved in the decision on mode of delivery. Health professionals need to be responsive to this variability and to agree on standards for communicating with women during pregnancy about the possibility of operative delivery and for debriefing women after caesarean section. sarean section, and women's satisfaction with this involvement. 相似文献
Design Observational study.
Setting The maternity unit in a large teaching hospital.
Sample One hundred and sixty-six women undergoing caesarean section.
Methods Interviews with the women on the third or fourth day postpartum, questionnaires sent to the women at 6 weeks and at 12 weeks postpartum, and extraction of information from the women's medical records.
Main outcome measures Women's knowledge, satisfaction, and involvement in making the decision concerning their caesarean section.
Results The majority of the women were satisfied with the information they received during pregnancy on caesarean section and with their involvement in making the decision, but the proportions were significantly higher for elective than emergency sections. For 7% of the women, maternal preference for caesarean section was a direct factor in making the decision. Just over half of the 166 women reported that they were not debriefed on the reasons for their caesarean section before their discharge from hospital. Almost a third of the women undergoing emergency caesarean section expressed negative feelings towards their delivery, compared with 13% of those undergoing elective caesarean sections.
Conclusion Women are not a homogeneous group in terms of their requirements for information, nor their desire to be involved in the decision on mode of delivery. Health professionals need to be responsive to this variability and to agree on standards for communicating with women during pregnancy about the possibility of operative delivery and for debriefing women after caesarean section. sarean section, and women's satisfaction with this involvement. 相似文献
68.
Allan “Ben” Smith Phyllis Butow Ian Olver Tim Luckett Peter Grimison Guy C. Toner Martin R Stockler Elizabeth Hovey John Stubbs Sandra Turner George Hruby Howard Gurney Mahmood Alam Keith Cox Madeleine T. King 《Journal of cancer survivorship》2016,10(2):223-233
Purpose
This study aimed to establish the prevalence, severity, and correlates of psychological distress and impaired generic health-related quality of life (HRQOL) in testicular cancer (TC) survivors.Methods
Men who had completed active anti-cancer treatment for TC between 6 months and 5 years previously showing no evidence of recurrence were recruited from 14 Australian cancer centers from September 2009 to February 2011. Participants completed a self-report questionnaire measuring demographic, disease, and treatment information, psychological distress (i.e., depression, anxiety, and stress; DASS21), generic health-related quality of life (HRQOL; SF-36v2), TC-specific HRQOL (EORTC QLQ-TC26), coping (MAC), social support (DUFSS), and unmet needs (CaSUN).Results
Of 486 eligible TC survivors, 244 (50.2 %) completed the questionnaire. Compared with normative data, TC survivors reported: small but statistically significant increases in mean levels of anxiety and depression; a greater prevalence of moderate to extremely severe anxiety (19 %) and depression (20 %); and significant deficits to mostly mental aspects of generic HRQOL. The most problematic TC-specific HRQOL issues (e.g., fear of recurrence) were also more mental than physical. In multiple regression analyses, the strongest correlates of psychological distress and impaired generic HRQOL were psychosocial (e.g., helpless/hopeless coping and lower social support) rather than disease or treatment factors.Conclusions
Generally, TC survivors appear to experience mild psychological distress and HRQOL impairments, while a vulnerable subgroup experience more severe morbidity.Implications for Cancer Survivors
There is a need to identify TC survivors at risk of poorer outcomes and for interventions to target the areas of greatest impairment (i.e., psychological distress and mental HRQOL).69.
Laura MC Welschen Patricia van Oppen Jacqueline M Dekker Lex M Bouter Wim AB Stalman Giel Nijpels 《BMC public health》2007,7(1):74
Background
In patients with type 2 diabetes, the risk for cardiovascular disease is substantial. To achieve a more favourable risk profile, lifestyle changes on diet, physical activity and smoking status are needed. This will involve changes in behaviour, which is difficult to achieve. Cognitive behavioural therapies focussing on self-management have been shown to be effective. We have developed an intervention combining techniques of Motivational Interviewing (MI) and Problem Solving Treatment (PST). The aim of our study is to investigate if adding a combined behavioural intervention to managed care, is effective in achieving changes in lifestyle and cardiovascular risk profile. 相似文献70.
Mild hypothermia during halothane-induced anesthesia decreases resistance to Staphylococcus aureus dermal infection in guinea pigs 总被引:1,自引:0,他引:1
Clark W. Sheffield MD ; Daniel I. Sessler MD ; Thomas K. Hunt MD ; Heinz Scheuenstuhl AB 《Wound repair and regeneration》1994,2(1):48-56
Because various immune functions are impaired at temperatures only 1 degrees to 3 degrees C less than normal, we tested the hypothesis that mild hypothermia during anesthesia impairs resistance to dermal infections. Guinea pigs were anesthetized for 6 hours with 1% inspired halothane. Their core temperatures were maintained at either 39 degrees C (normal for guinea pigs, n = 12) or 36 degrees C (n = 12). Two hours after induction of anesthesia, three doses each of Staphylococcus aureus (10(8), 10(7), and 10(6) organisms) were injected intradermally at nine sites on each animal's back. Core temperatures were not controlled after recovery from the anesthetic, and animals in each group were maintained in the same environment. Four days after anesthesia, each injection site was excised to obtain a count of viable bacteria. Subcutaneous oxygen partial pressure values, averaged over time, were 53 +/- 3 mm Hg (mean +/- SEM) in the hypothermic group and 62 +/- 4 mm Hg in the normothermic group (p = 0.06). Capillary perfusion, as assessed by laser Doppler flowmetry, was comparable in the two groups. One day after injection of 10(8) bacteria, the area of induration was 89 +/- 11 mm(2) in the hypothermic group but only 61 +/- 6 mm(2) in the normothermic group (p < 0.05). On postanesthetic day 4, the area of induration was 72 +/- 6 and 59 +/- 6 mm(2) in the hypothermic and normothermic groups, respectively (p > 0.05). After inoculation with 10(8) bacteria, the fraction recovered was 1.0 +/- 0.2 in the hypothermic groups and 0.6 +/- 0.2 in the normothermic group (p < 0.05). After inoculation with 10(7) and 10(6) bacteria, the fraction recovered was less than 0.2, and no difference was found between the hypothermic and normothermic animals. Thus mild hypothermia during halothane-induced anesthesia slightly impairs resistance to dermal infection. 相似文献