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111.
Rectal cancer is a major health concern in the United States, with an estimated 40,570 new cases diagnosed in 2004. There are 4 major goals in the treatment of a patient with rectal cancer: local control; long-term survival; preservation of anal sphincter, bladder, and sexual function; and maintenance or improvement in quality of life. Recent advances have been made in preoperative staging, local and radical surgical therapy, the importance of distal and circumferential resection margins, postoperative preservation of the anal sphincter mechanism and genitourinary function, and the role of laparoscopy in the treatment of these patients. Our aim is to outline some of the important surgical issues surrounding the management of patients with early-stage (T1/T2 N0) or locally advanced (T3/T4 and/or N1) rectal cancer. 相似文献
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González CA Pera G Agudo A Palli D Krogh V Vineis P Tumino R Panico S Berglund G Simán H Nyrén O Agren A Martinez C Dorronsoro M Barricarte A Tormo MJ Quiros JR Allen N Bingham S Day N Miller A Nagel G Boeing H Overvad K Tjonneland A Bueno-De-Mesquita HB Boshuizen HC Peeters P Numans M Clavel-Chapelon F Helen I Agapitos E Lund E Fahey M Saracci R Kaaks R Riboli E 《International journal of cancer. Journal international du cancer》2003,107(4):629-634
Smoking has recently been recognised as causally associated with the development of gastric cancer (GC). However, evidence on the effect by sex, duration and intensity of smoking, anatomic subsite and cessation of smoking is limited. Our objective was to assess the relation between tobacco use and GC incidence in the European Prospective Investigation into Cancer and Nutrition (EPIC). We studied data from 521,468 individuals recruited from 10 European countries taking part in the EPIC study. Participants completed lifestyle questionnaires that included questions on lifetime consumption of tobacco and diet in 1991-1998. Participants were followed until September 2002, and during that period 305 cases of stomach cancer were identified. After exclusions, 274 were eligible for the analysis, using the Cox proportional hazard model. After adjustment for educational level, consumption of fresh fruit, vegetables and preserved meat, alcohol intake and body mass index (BMI), there was a significant association between cigarette smoking and gastric cancer risk: the hazard ratio (HR) for ever smokers was 1.45 (95% confidence interval [CI] = 1.08-1.94). The HR of current cigarette smoking was 1.73 (95% CI = 1.06-2.83) in males and 1.87 (95% CI = 1.12-3.12) in females. Hazard ratios increased with intensity and duration of cigarette smoked. A significant decrease of risk was observed after 10 years of quitting smoking. A preliminary analysis of 121 cases with identified anatomic site showed that current cigarette smokers had a higher HR of GC in the cardia (HR = 4.10) than in the distal part of the stomach (HR = 1.94). In this cohort, 17.6 % (95% CI = 10.5-29.5 %) of GC cases may be attributable to smoking. Findings from this large study support the causal relation between smoking and gastric cancer in this European population. Stomach cancer should be added to the burden of diseases caused by smoking. 相似文献
114.
Amygdalar atrophy in panic disorder patients detected by volumetric magnetic resonance imaging 总被引:6,自引:0,他引:6
Massana G Serra-Grabulosa JM Salgado-Pineda P Gastó C Junqué C Massana J Mercader JM Gómez B Tobeña A Salamero M 《NeuroImage》2003,19(1):80-90
It has been suggested that the pathophysiology of panic disorder (PD) may involve abnormalities in several brain structures, including the amygdala. To date, however, no study has used quantitative structural neuroimaging techniques to examine amygdalar anatomy in this disorder. Volumetric magnetic resonance imaging (MRI) studies of the amygdalas, hippocampi, and temporal lobes were conducted in 12 drug-free, symptomatic PD patients (six females and six males), and 12 case-matched healthy comparison subjects. Volumetric MRI data were normalized for brain size. PD patients were found to have smaller left-sided and right-sided amygdalar volumes than controls. No differences were found in either hippocampi or temporal lobes. These findings provide new evidence of changes in amygdalar structure in PD and warrant further anatomical and MRI brain studies of patients with this disorder. 相似文献
115.
Granulocyte colony-stimulating factor in the treatment of high-risk febrile neutropenia: a multicenter randomized trial 总被引:1,自引:0,他引:1
García-Carbonero R Mayordomo JI Tornamira MV López-Brea M Rueda A Guillem V Arcediano A Yubero A Ribera F Gómez C Trés A Pérez-Gracia JL Lumbreras C Hornedo J Cortés-Funes H Paz-Ares L 《Journal of the National Cancer Institute》2001,93(1):31-38
BACKGROUND: Granulocyte colony-stimulating factors (G-CSFs) have been shown to help prevent febrile neutropenia in certain subgroups of cancer patients undergoing chemotherapy, but their role in treating febrile neutropenia is controversial. The purpose of our study was to evaluate-in a prospective multicenter randomized clinical trial-the efficacy of adding G-CSF to broad-spectrum antibiotic treatment of patients with solid tumors and high-risk febrile neutropenia. METHODS: A total of 210 patients with solid tumors treated with conventional-dose chemotherapy who presented with fever and grade IV neutropenia were considered to be eligible for the trial. They met at least one of the following high-risk criteria: profound neutropenia (absolute neutrophil count <100/mm(3)), short latency from previous chemotherapy cycle (<10 days), sepsis or clinically documented infection at presentation, severe comorbidity, performance status of 3-4 (Eastern Cooperative Oncology Group scale), or prior inpatient status. Eligible patients were randomly assigned to receive the antibiotics ceftazidime and amikacin, with or without G-CSF (5 microg/kg per day). The primary study end point was the duration of hospitalization. All P values were two-sided. RESULTS: Patients randomly assigned to receive G-CSF had a significantly shorter duration of grade IV neutropenia (median, 2 days versus 3 days; P = 0.0004), antibiotic therapy (median, 5 days versus 6 days; P = 0.013), and hospital stay (median, 5 days versus 7 days; P = 0.015) than patients in the control arm. The incidence of serious medical complications not present at the initial clinical evaluation was 10% in the G-CSF group and 17% in the control group (P = 0.12), including five deaths in each study arm. The median cost of hospital stay and the median overall cost per patient admission were reduced by 17% (P = 0.01) and by 11% (P = 0.07), respectively, in the G-CSF arm compared with the control arm. CONCLUSIONS: Adding G-CSF to antibiotic therapy shortens the duration of neutropenia, reduces the duration of antibiotic therapy and hospitalization, and decreases hospital costs in patients with high-risk febrile neutropenia. 相似文献
116.
Surgical Debulking and Intraperitoneal Chemotherapy for Established Peritoneal Metastases From Colon and Appendix Cancer 总被引:2,自引:1,他引:1
Alfred T Culliford IV MD Ari D. Brooks MD Sunil Sharma MD Leonard B. Saltz MD Gary K. Schwartz MD Eileen M. O’Reilly MD David H. Ilson MD Nancy E. Kemeny MD David P. Kelsen MD Jose G. Guillem MD W Douglas Wong MD Alfred M. Cohen MD Philip B. Paty MD 《Annals of surgical oncology》2001,8(10):787-795
Background: Aggressive treatment of peritoneal metastases from colon cancer by surgical cytoreduction and infusional intraperitoneal (IP) chemotherapy may benefit selected patients. We reviewed our institutional experience to assess patient selection, complications, and outcome.Methods: Patients having surgical debulking and IP 5-fluoro-2-deoxyuridine (FUDR) plus leucovorin (LV) for peritoneal metastases from 1987 to 1999 were evaluated retrospectively.Results: There were 64 patients with a mean age of 50 years. Primary tumor sites were 47 in the colon and 17 in the appendix. Peritoneal metastases were synchronous in 48 patients and metachronous in 16 patients. Patients received IP FUDR (1000 mg/m2 daily for 3 days) and IP leucovorin (240 mg/m2) with a median cycle number of 4 (range, 1–28). The median number of complications was 1 (range, 0–5), with no treatment related mortality. Only six patients (9%) required termination of IP chemotherapy because of complications. The median follow-up was 17 months (range, 0–132 months). The median survival was 34 months (range, 2–132); 5-year survival was 28%. Lymph node status, tumor grade, and interval to peritoneal metastasis were not statistically significant prognostic factors for survival. Complete tumor resection was significant on multivariate analysis (P = .04), with a 5-year survival of 54% for complete (n = 19) and 16% for incomplete (n = 45) resection.Conclusions: Surgical debulking and IP FUDR for peritoneal metastases from colon cancer can be accomplished safely and has yielded an overall 5-year survival of 28%. Complete resection is associated with improved survival (54% at 5 years) and is the most important prognostic indicator.Presented in part at the 54th Annual Cancer Symposium of the Society of Surgical Oncology, Washington, DC, March 15–18, 2001. 相似文献
117.
Dissociating memory processes involved in direct and indirect tests with ERPs to unfamiliar faces 总被引:2,自引:0,他引:2
Event-related potentials (ERPs) were recorded during indirect and direct memory tests for unfamiliar faces. In both tests, ERPs displayed the usual positive shift known as the ERP repetition effect. In the indirect test, this effect includes parietal effect (the usual N400 effect) and a right fronto-central effect. Both effects are also present in the direct test. Two additional effects are present only in the direct test. These effects are an early fronto-polar effect and a late posterior effect (the usual P600 effect). These findings are taken as support for the distinction between 'associative' processes elicited in both the direct and indirect tests, and 'episodic' processes elicited only in the direct test. This task dissociation could well provide a scalp correlate of the distinction between the neocortical and cortico-limbic systems that have been shown to contribute respectively to associative and episodic processing. In addition, it is proposed that the dissociation between the two frontal effects could be accounted for by a distinction between the processing of intrinsic vs. extrinsic contextual attributes as a function of the task requirements. 相似文献
118.
Cefalu WT; Wagner JD; Bell-Farrow AD; Edwards IJ; Terry JG; Weindruch R; Kemnitz JW 《Toxicological sciences》1999,52(2):49-55
Caloric restriction (CR) has been observed to retard aging processes and
extend the maximum life span in rodents. In an effort to evaluate the
effect of this nutritional intervention on physiologic variables in higher
species, several nonhuman primate trials are ongoing. In particular, a
study evaluating the independent effect of CR on the extent of
atherosclerosis was initiated in 1993 in 32 adult cynomolgus monkeys.
Therefore, the trial was designed to achieve identical cholesterol intake
after animals were randomized to a control group or a calorie-restricted
group (30% reduction from baseline caloric intake). The animals were
routinely evaluated for glycated proteins, plasma insulin and glucose
levels, insulin sensitivity, and specific measures for abdominal fat
distribution by CT scans over a 4-year interval. The results from 4 years
of intervention demonstrate that CR improves cardiovascular risk factors
(such as visceral fat accumulation) and improves insulin sensitivity. In
contrast to other primate studies with normolipidemic animals, CR had no
independent effects on plasma lipid levels and composition in the presence
of equivalent amounts of dietary cholesterol intake. Preliminary analysis
of atherosclerotic lesion extent in the abdominal aorta has failed to
demonstrate differences between control animals and CR animals. Follow- up
studies are being conducted to determine the effect of CR on
atherosclerosis extent in coronary and carotid arteries.
相似文献
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120.
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