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61.
Objective—To evaluate the effects of α tocopherol and β carotene supplements on recurrence and progression of angina symptoms, and incidence of major coronary events in men with angina pectoris.
Design—Placebo controlled clinical trial.
Setting—The Finnish α tocopherol β carotene cancer prevention study primarily undertaken to examine the effects of α tocopherol and β carotene on cancer.
Subjects—Male smokers aged 50-69 years who had angina pectoris in the Rose chest pain questionnaire at baseline (n = 1795).
Interventions—α tocopherol (vitamin E) 50 mg/day, β carotene 20 mg/day or both, or placebo in 2 × 2 factorial design.
Main outcome measures—Recurrence of angina pectoris at annual follow up visits when the questionnaire was readministered; progression from mild to severe angina; incidence of major coronary events (non-fatal myocardial infarction and fatal coronary heart disease).
Results—There were 2513 recurrences of angina pectoris during follow up (median 4 years). Compared to placebo, the odds ratios for recurrence in the active treatment groups were: α tocopherol only 1.06 (95% confidence interval (CI) 0.85 to 1.33), α tocopherol and β carotene 1.02 (0.82 to 1.27), β carotene only 1.06 (0.84 to 1.33). There were no significant differences in progression to severe angina among the groups given supplements or placebo. Altogether 314 major coronary events were observed during follow up (median 5.5 years) and the risk for them did not differ significantly among the groups given supplements or placebo.
Conclusions—There was no evidence of beneficial effects for α tocopherol or β carotene supplements in male smokers with angina pectoris, indicating no basis for therapeutic or preventive use of these agents in such patients.

Keywords: antioxidants;  angina pectoris;  prevention;  vitamin supplements  相似文献   
62.

Background

Visual field defects (VFDs) negatively affect activities of daily living and rehabilitation following aneurysmal subarachnoid haemorrhage (aSAH). The aim here was to assess VFDs in patients with aSAH and their associations with age, gender, aSAH severity, and clinical outcome.

Methods

Patients admitted to Helsinki University Central Hospital and treated during 2011 were participants in this prospective study. Findings obtained with the Octopus 900 perimeter (Haag-Streit Inc, Koenic, Switzerland), the Goldmann perimeter (Haag-Streit Inc, Bern, Switzerland), or the confrontation visual field test on admission and 3 days, 14 days, 2 to 4 months, and 6 months postoperatively were assigned to 16 classes. Associations between post-chiasmal VFDs and relevant clinical, radiological, and demographic data were analysed with uni- and multivariate logistic regression.

Results

Of 105 survivors at 6 months, 20 (19 %) had VFDs occurring for aneurysm- or operation-related reasons; homonymous hemianopias or quadrantanopias were the most common finding, occurring in 16 patients (15 %). Posterior ischaemic optic neuropathy presented in two patients (2 %). Ten survivors (10 %) no longer fulfilled visual field requirements for driving licences. Significant associations emerged between VFDs at 6 months and the Hunt and Hess (H&H), World Federation of Neurosurgical Societies (WFNS), and Fisher grades on admission, presence of intracerebral haemorrhage (ICH), hydrocephalus, or postoperative infarction, and higher modified Rankin Scale scores at 6 months. Multivariate logistic regression showed the H&H grade and presence of ICH to independently predict VFDs.

Conclusions

Assessing VFDs is advisable, especially among patients with poor-grade aSAH (H&H grade IV or V) and ICH.  相似文献   
63.
A 34-y-old man presented to Naivasha District Hospital (NDH) in Naivasha Town, Kenya, with near-complete below-knee amputation and hemorrhage after a hippopotamus attack. Residents from the University of Washington (UW), Departments of Surgery, Anesthesia, and Medicine, were rotating at NDH with the Clinical Education Partnership Initiative, a joint venture of UW and University of Nairobi. These providers met the patient in the operating theater. The leg was mangled with severely traumatized soft tissues and tibia–fibula fractures. The visiting UW Surgery resident (R3) and an NDH medical officer (second-year house officer) performed emergency below-knee completion amputation—the first time either had performed this operation. The three major vessel groups were identified and ligated. Sufficient gastrocnemius and soleus were preserved for future stump construction. The wound was washed out, packed with betadine-soaked gauze, and wrapped in an elasticized bandage. Broad-spectrum antibiotics were initiated. Unfortunately, the patient suffered infection and was revised above the knee. After a prolonged course, the patient recovered well and was discharged home. NDH house officers and UW trainees collaborated successfully in an emergency and conducted the postoperative care of a patient with a serious and challenging injury. Their experience highlights the importance of preparedness, command of surgical basics, humility, learning from mistakes, the expertise of others, a digitally connected surgical community, and the role of surgery in global health. These lessons will be increasingly pertinent as surgical training programs create opportunities for their residents to work in developing countries; many of these lessons are equally applicable to surgical practice in the developed world.  相似文献   
64.
Inflammasome is an intracellular molecular platform of the innate immunity that is a key mediator of inflammation. The inflammasome complex detects pathogens and different danger signals, and triggers cysteine protease caspase-1-dependent processing of pro-inflammatory cytokines IL-1β, and IL-18 in dendritic cells and macrophages. Previously, we have shown that water-damaged building associated trichothecene mycotoxins, including roridin A, trigger IL-1β and IL-18 secretion in human macrophages. However, the molecular basis as well as mechanism behind this trichothecene-induced cytokine secretion has remained uncharacterized. Here, we show that the trichothecene-induced IL-1β secretion is dependent on NLRP3 inflammasome in human primary macrophages. Pharmacological inhibition and small interfering RNA approach showed that the trichothecene-induced NLRP3 inflammasome activation is mediated through ATP-gated P2X7 receptor. Moreover, we show that trichothecene-triggered NLRP3 inflammasome activation is dependent on Src tyrosine kinase activity. In addition, gene silencing of c-Cbl, a negative autophagy-related regulator of c-Src, resulted in enhanced secretion of IL-1β and IL-18 in response to trichothecene mycotoxin stimulation in human macrophages. In conclusion, our results suggest that roridin A, a fungal trichothecene mycotoxin, acts as microbial danger signals that trigger activation of NLRP3 inflammasome through P2X7R and Src tyrosine kinase signaling dependent pathway in human primary macrophages.  相似文献   
65.
The ability of cells to adhere to substrates is an important factor for the effectiveness of biotechnologies and bioimplants. This research demonstrates that the statistical distribution of the sizes of the cells (Saccharomyces cerevisiae) attached to the substrate surface correlates with the statistical distribution of electrical potential on the substrate’s surface. Hypothetically, this behavior should be taken into consideration during the processing of surfaces when cell adhesion based on cell size is required.  相似文献   
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69.
Summary The urinary excretion of albumin and -2microglubulin was measured by radioimmunoassay in 64 children and adolescents with Type 1 (insulin dependent) diabetes and in 68 non-diabetic subjects aged from 9 to 19 years. At rest the albumin excretion of the diabetic subjects did not differ from that of the non-diabetic children and adolescents but during exercise the albumin excretion was significantly higher in children and adolescents with Type 1 diabetes (p<0.02). The excretion rate of 2-microglobulin in diabetic subjects did not differ from that of the healthy subjects. Both at rest and during exercise the albumin excretion rate was highest in those diabetics with poorest metabolic control of their disease.  相似文献   
70.
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