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91.
The relationship between dietary fat intake and risk of colorectal cancer: evidence from the combined analysis of 13 case-control studies 总被引:3,自引:0,他引:3
Geoffrey R. Howe Kristan J. Aronson Enrique Benito Roberto Castelleto Jacqueline Cornée Stephen Duffy Richard P. Gallagher José M. Iscovich Jiao Deng-ao Rudolf Kaaks Gabriel A. Kune Susan Kune Hin P. Lee Marion Lee Anthony B. Miller Ruth K. Peters John D. Potter Elio Riboli Martha L. Slattery Dimitrios Trichopoulos Albert Tuyns Anastasia Tzonou Lyndsey F. Watson Alice S. Whittemore Anna H. Wu-Williams Zheng Shu 《Cancer causes & control : CCC》1997,8(2):215-228
The objective of this study was to examine the effects of the intakeof dietary fat upon colorectal cancer risk in a combined analysis of datafrom 13 case-control studies previously conducted in populations withdiffering colorectal cancer rates and dietary practices. Original datarecords for 5,287 cases of colorectal cancer and 10,470 controls werecombined. Logistic regression analysis was used to estimate odds ratios (OR)for intakes of total energy, total fat and its components, and cholesterol.Positive associations with energy intake were observed for 11 of the 13studies. However, there was little, if any, evidence of anyenergy-independent effect of either total fat with ORs of 1.00, 0.95, 1.01,1.02, and 0.92 for quintiles of residuals of total fat intake (P trend =0.67) or for saturated fat with ORs of 1.00, 1.08, 1.06, 1.21, and 1.06 (Ptrend = 0.39). The analysis suggests that, among these case-control studies,there is no energy-independent association between dietary fat intake andrisk of colorectal cancer. It also suggests that simple substitution of fatby other sources of calories is unlikely to reduce meaningfully the risk ofcolorectal cancer. 相似文献
92.
Lene Mellemkjær Christoffer Johansen Martha S. Linet Gloria Gridley Jørgen H. Olsen 《Cancer causes & control : CCC》1998,9(2):183-187
Objective: Epidemiologic studies have not been able definitely to exclude that appendectomy carries a cancer risk. This study was conducted to clarify whether appendectomy is associated with a subsequent increase in cancer risk, since appendectomy is frequently an elective procedure. Methods: The present study included more than 82,000 persons who underwent appendectomy for acute appendicitis during 1977-89 according to the nation-wide Danish Hospital Discharge Register. During a follow-up interval of up to 17 years, cancer incidence was assessed by linkage to the Danish Cancer Registry and compared with the incidence in the general population of Denmark. Results: The total number of malignancies among appendectomized persons was 1.05 times higher than expected with 95 percent confidence intervals of 0.99-1.11. There was no clear significant excess of any specific cancer type. Conclusion: During a postsurgery period of nearly two decades, results of our study did not support the hypothesis that either appendectomy or acute appendicitis are likely to be associated with malignant neoplasms. 相似文献
93.
94.
Lori D Fineman Michelle A LaBrecque Mei-Chiung Shih Martha A Q Curley 《Pediatric critical care medicine》2006,7(5):413-422
OBJECTIVE: To describe the effects of prone positioning on airway management, mechanical ventilation, enteral nutrition, pain and sedation management, and staff utilization in infants and children with acute lung injury. DESIGN: Secondary analysis of data collected in a multiple-center, randomized, controlled clinical trial of supine vs. prone positioning. SETTING: Seven pediatric intensive care units located in the United States. PATIENTS: One hundred and two pediatric patients (51 prone and 51 supine) with acute lung injury. INTERVENTIONS: Patients randomized to the supine group remained supine. Patients randomized to the prone group were positioned prone per protocol during the acute phase of their illness for a maximum of 7 days. Both groups were managed using ventilator and sedation protocols and nutrition and skin care guidelines. MEASUREMENTS AND MAIN RESULTS: Airway management and mechanical ventilatory variables before and after repositioning, enteral nutrition management, pain and sedation management, staff utilization, and adverse event data were collected for up to 28 days after enrollment. There were a total of 202 supine-prone-supine cycles. There were no differences in the incidence of endotracheal tube leak between the two groups (p = .30). Per protocol, 95% of patients remained connected to the ventilator during repositioning. The inadvertent extubation rate was 0.85 for the prone group and 1.03 for the supine group per 100 ventilator days (p = 1.00). There were no significant differences in the initiation of trophic (p = .24), advancing (p = .82), or full enteral feeds (p = .80) between the prone and supine groups; in the average pain (p = .81) and sedation (p = .18) scores during the acute phase; and in the amount of comfort medications received between the two groups (p = .91). There were no critical events during a turn procedure. While prone, two patients experienced an obstructed endotracheal tube. One patient, supported on high-frequency oscillatory ventilation, experienced persistent hypercapnea when prone and was withdrawn from the study. The occurrence of pressure ulcers was similar between the two groups (p = .71). Compared with the supine group, more staff (p = .001) and more time were necessary to reposition patients in the prone group. CONCLUSIONS: Our data show that prone positioning can be safely performed in critically ill pediatric patients and that these patients can be safely managed while in the prone position for prolonged periods of time. 相似文献
95.
Predicting abdominal adipose tissue in overweight Latino youth. 总被引:1,自引:0,他引:1
Geoff D C Ball Terry T K Huang Martha L Cruz Gabriel Q Shaibi Marc J Weigensberg Michael I Goran 《International journal of pediatric obesity》2006,1(4):210-216
OBJECTIVES: 1) Examine associations between visceral adipose tissue (VAT), subcutaneous abdominal adipose tissue (SAAT), and anthropometric and demographic variables; 2) generate and cross-validate prediction equations for estimating VAT and SAAT in overweight Latino children. STUDY DESIGN: Cross-sectional. PARTICIPANTS: 196 overweight 8-13-year-old Latino youth. Two-thirds (n = 131) were randomly assigned to a development group to generate prediction equations for VAT and SAAT; one-third (n = 65) was used as a cross-validation group. METHODS AND PROCEDURES: Anthropometric measurements (height, weight, skinfold thicknesses, and circumferences) were performed. VAT and SAAT were measured using magnetic resonance imaging (MRI). RESULTS: The strongest univariate correlate for VAT was waist circumference (WC) (r = 0.65, p < 0.01) while the strongest correlate for SAAT was hip circumference (r = 0.88, p < 0.001). Regression analyses showed approximately 50% of the variance in VAT was explained by WC (43.8%), Tanner stage (4.2%) and calf skinfold (1.7%). Variance in the SAAT model was explained by WC (77.8%), triceps skinfold (4.2%) and gender (2.3%). Residual analyses showed no bias in either equation. Though mean differences between measured and predicted VAT and SAAT were small, there was a large degree of variability at the individual level especially for VAT. CONCLUSIONS: Both VAT and SAAT prediction equations performed well at the group level, but the relatively high degree of variability suggests limited clinical utility of the VAT equation. MRI is currently required to derive an accurate measure of VAT at the individual level. 相似文献
96.
Luis F Porrata Morie A Gertz Mark R Litzow Martha Q Lacy Angela Dispenzieri David J Inwards Stephen M Ansell Ivanna N M Micallef Dennis A Gastineau Michele Elliott William J Hogan Suzanne R Hayman Ayalew Tefferi Svetomir N Markovic 《Clinical cancer research》2005,11(3):1210-1218
PURPOSE: Absolute lymphocyte count recovery at day 15 (ALC-15) post-autologous stem cell transplantation (ASCT) is a powerful prognostic indicator for survival for multiple hematologic malignancies and metastatic breast cancer. The relationship of ALC-15 with clinical outcomes in primary systemic amyloidosis is unknown. EXPERIMENTAL DESIGN: We evaluated 145 consecutive patients with primary systemic amyloidosis who underwent ASCT at the Mayo Clinic from 1996 to 2003. The ALC-15 threshold was set at 500 cells/microL based on our previous observations. RESULTS: The median patient follow-up was 22 months (range, 3-87 months). Higher hematologic complete response was observed in patients with an ALC-15 > or = 500 cells/microL compared with patients with an ALC-15 < 500 cells/microL (41% versus 21%, P < 0.0008, respectively). The median overall survival and progression-free survival times were significantly better for the 59 patients that achieved an ALC-15 > or = 500 cells/microL compared with 86 patients with ALC-15 < 500 cells/microL (not reached versus 53 months, P < 0.0003 and not reached versus 27 months, P < 0.0001, respectively). Multivariate analysis showed ALC-15 to be an independent prognostic factor for overall survival and progression-free survival. CONCLUSIONS: ALC-15 > or = 500 cells/microL is associated with significantly improved clinical outcomes following ASCT in patients with primary systemic amyloidosis. 相似文献
97.
Shaji Kumar S Vincent Rajkumar Robert A Kyle Martha Q Lacy Angela Dispenzieri Rafael Fonseca John A Lust Morie A Gertz Philip R Greipp Thomas E Witzig 《Journal of clinical oncology》2005,23(24):5668-5674
PURPOSE: Monoclonal gammopathy of undetermined significance (MGUS) progresses to multiple myeloma or another related plasma cell disorder (PCD) at a rate of approximately 1% per year. Identification of patients with MGUS at high risk of progression will allow development of preventive strategies. We studied the prognostic value of circulating plasma cells (PCs) in patients with MGUS to predict progression. PATIENTS AND METHODS: Patients were eligible for this retrospective analysis if they were seen at the Mayo Clinic between 1984 and 1997, were diagnosed with MGUS, and had an analysis of the peripheral blood for circulating PCs by the slide-based immunofluorescence method. Patients were observed for progression to another PCD. RESULTS: Three hundred twenty-five patients were eligible and 63 (19%) had circulating PCs. Patients with circulating PCs were twice as likely (hazard ratio, 2.1) to experience progression to another PCD (most commonly myeloma), compared with those without circulating PCs (95% CI, 1.1 to 4.3; P = .03). In patients with circulating PCs, the median progression-free survival was 138 months compared with a median not yet reached for those without circulating PCs (P = .028). The median overall survival also was shorter for those with circulating PCs. Other factors with prognostic value were high levels of M protein and non-immunoglobulin G heavy-chain type. CONCLUSION: The presence of circulating PCs, especially when combined with other known prognostic factors such as M protein concentration and immunoglobulin isotype, identify a group of individuals with MGUS at higher risk of progression to overt multiple myeloma. 相似文献
98.
Terryl J Hartman Binbing Yu Paul S Albert Martha L Slattery Electra Paskett James Walter Kikendall Frank Iber Brenda K Brewer Arthur Schatzkin Elaine Lanza 《Cancer epidemiology, biomarkers & prevention》2005,14(10):2359-2365
The Polyp Prevention Trial was designed to evaluate the effects of a high-fiber (18 g/1,000 kcal), high-fruit and -vegetable (3.5 servings/1,000 kcal), low-fat (20% energy) diet on recurrence of adenomatous polyps. Participants > or =35 years of age, with histologically confirmed colorectal adenoma(s) removed in the prior 6 months, were randomized to the intervention or control group. Demographic, dietary, and clinical information, including use of nonsteroidal anti-inflammatory drugs (NSAID), was collected at baseline and four annual visits. Adenoma recurrence was found in 754 of 1,905 participants and was not significantly different between groups. NSAID use was associated with a significant reduction in recurrence [odds ratio (OR), 0.77; 95% confidence interval (95% CI), 0.63-0.95]. In this analysis, NSAIDs modified the association between the intervention and recurrence at baseline (P = 0.02) and throughout the trial (P = 0.008). Among participants who did not use NSAIDs, the intervention was in the protective direction but did not achieve statistical significance (OR, 0.87; 95% CI, 0.69-1.09). The intervention was protective among males who did not use NSAIDs at baseline (OR, 0.71; 95% CI, 0.54-0.94), but not among NSAIDs users (OR, 1.09; 95% CI, 0.74-1.62). For females, corresponding OR estimates were 1.28 (95% CI, 0.86-1.90) and 2.30 (95% CI, 1.24-4.27), respectively. The protective association observed for NSAID use was stronger among control (OR, 0.63; 95% CI, 0.47-0.84) than for intervention group participants (OR, 0.97; 95% CI, 0.74-1.28). These results should be interpreted cautiously given that they may have arisen by chance in the course of examining multiple associations and Polyp Prevention Trial study participants were not randomly assigned to both dietary intervention and NSAID use. Nevertheless, our results suggest that adopting a low-fat, high-fiber diet rich in fruits and vegetables may lower the risk of colorectal adenoma recurrence among individuals who do not regularly use NSAIDs. 相似文献
99.
Familial aggregation and heterogeneity of non-Hodgkin lymphoma in population-based samples. 总被引:4,自引:0,他引:4
Lynn R Goldin Ola Landgren Mary L McMaster Gloria Gridley Kari Hemminki Xinjun Li Lene Mellemkjaer J?rgen H Olsen Martha S Linet 《Cancer epidemiology, biomarkers & prevention》2005,14(10):2402-2406
The importance of genetic factors in the etiology of non-Hodgkin lymphoma (NHL) is suggested by case-control and cohort studies. Most previous studies have been too small to estimate accurately risks of specific categories of lymphoproliferative malignancies in relatives of NHL cases or to quantify the contribution of NHL case characteristics to familial risk. We have overcome sample size limitations and potential recall bias by using large databases from Sweden and Denmark. Diagnoses of lymphoproliferative malignancies were compared in 70,006 first-degree relatives of 26,089 NHL cases (including 7,432 with subtype information) versus 161,352 first-degree relatives of 58,960 matched controls. Relatives of NHL cases were at significantly increased risk for NHL [relative risk (RR), 1.73; 95% confidence interval (95% CI), 1.39-2.15], Hodgkin lymphoma (RR, 1.41; 95% CI, 1.0-1.97), and nonsignificantly for chronic lymphocytic leukemia (CLL; RR, 1.31; 95% CI, 0.93-1.85). No increased risk was found for multiple myeloma among case relatives. Findings with respect to siblings compared with parents and offspring or with respect to age at diagnosis of proband were inconsistent. In both populations, relatives of cases with an aggressive NHL subtype were at substantially increased risk of NHL (combined RR, 3.56; 95% CI, 1.80-7.02). We conclude that NHL has an important familial component, which is shared with Hodgkin lymphoma and CLL. We estimate that the absolute lifetime risk for a first-degree relative of an NHL case to develop NHL is 3.6% (compared with a population risk of 2.1%) and higher if the index case had an aggressive subtype of NHL. 相似文献
100.
Cerebrovascular responses to somatomotor stimulation in Parkinson’s disease: A multivariate analysis
Sam C Barnes Ronney B Panerai Lucy Beishon Martha Hanby Thompson G Robinson Victoria J Haunton 《Journal of cerebral blood flow and metabolism》2022,42(8):1547
Parkinson’s disease (PD) is a common neurodegenerative disorder, yet little is known about cerebral haemodynamics in this patient population. Previous studies assessing dynamic cerebral autoregulation (dCA), neurovascular coupling (NVC) and vasomotor reactivity (VMR) have yielded conflicting findings. By using multi-variate modelling, we aimed to determine whether cerebral blood flow (CBF) regulation is impaired in PD patients.55 healthy controls (HC) and 49 PD patients were recruited. PD subjects underwent a second recording following a period of abstinence from their anti-Parkinsonian medication. Continuous bilateral transcranial Doppler in the middle cerebral arteries, beat-to-beat mean arterial blood pressure (MAP; Finapres), heart rate (HR; electrocardiogram), and end-tidal CO2 (EtCO2; capnography) were measured. After a 5-min baseline period, a passive motor paradigm comprising 60 s of elbow flexion was performed. Multi-variate modelling quantified the contributions of MAP, ETCO2 and neural stimulation to changes in CBF velocity (CBFV). dCA, VMR and NVC were quantified to assess the integrity of CBF regulation.Neural stimulation was the dominant input. dCA, NVC and VMR were all found to be impaired in the PD population relative to HC (p < 0.01, p = 0.04, p < 0.01, respectively). Our data suggest PD may be associated with depressed CBF regulation. This warrants further assessment using different neural stimuli. 相似文献