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81.
The alcohol availability literature indicates that under some conditions, physical availability is positively associated with per capita alcohol consumption. Smart (1980) suggested that at the individual level, subjective and social aspects of availability may mediate and outweigh the influence of physical availability. The study described here examined the simultaneous effects of physical, subjective, and social availability on alcohol consumption. Standardized telephone interviews were conducted with 781 adult drinkers. As hypothesized, physical availability was not a significant multivariate predictor of alcohol consumption for residents of high, medium, and low alcohol outlet density counties in Michigan (USA). Subjective and social availability indicators were significant predictors of alcohol consumption. Similar patterns of results were found in multiple regression analyses for blacks and whites and women and men, although blacks and women consumed less alcohol than did whites and men. The theoretical and practical implications of these results are discussed. 相似文献
82.
Arterial blood-flow waveform measurement in intact animals: new digital radiographic technique 总被引:1,自引:0,他引:1
With a new radiographic method to determine the pulsatile flow pattern in an imaged artery, flow velocity is determined by tracking the movement of contrast material along the artery over time. Flow velocity is multiplied by an automatically determined cross-sectional area of the artery to determine blood flow. Pulsatile blood-flow waveforms were determined by radiographic and electromagnetic techniques in each femoral artery of four dogs while flow conditions were varied. Peak and average blood flows measured by the two techniques were highly correlated (r = .97 and .95, respectively). The closest agreement between the flow waveforms measured by the electromagnetic and radiographic techniques was found under normal flow conditions. The radiographically derived flow waveforms tended to be noisy at low blood-flow rates, and instantaneous blood-flow rates exceeding 700 ml/min were underestimated. 相似文献
83.
Percutaneous angioplasty in clinical management of renovascular hypertension: initial and long-term results 总被引:1,自引:0,他引:1
Martin LG; Price RB; Casarella WJ; Sones PJ; Wells JO Jr; Zellmer RA; Chuang VP; Silbiger ML Jr; Berkman WA 《Radiology》1985,155(3):629-633
Between January 1980 and July 1983, percutaneous transluminal angioplasty was attempted on 137 stenotic renal arteries in 100 patients. At termination of follow-up studies (3-39 months, mean of 16 months), 70% of those treated for hypertension had benefited from the procedure. Stenosis secondary to fibromuscular dysplasia responded better than stenosis from arteriosclerosis (85% and 65% of the patients, respectively). Benefit was minimal for those with stenosis of the renal artery ostium or renal insufficiency. Determining levels of renal vein renin before angioplasty is helpful in selecting patients; following angioplasty, this has considerable significance in predicting the success of the procedure. 相似文献
84.
85.
The Enhancing Effect of Spawning on Elimination of a Persistent Polychlorinated Biphenyl from Female Yellow Perch 总被引:3,自引:1,他引:2
The Enhancing Effect of Spawning on Elimination of a PersistentPolychlorinated Biphenyl from Female Yellow Perch. VODICNIK,M. J., AND PETERSON, R. E. (1985). Fundam. Appl. Toxicol. 5,770776. Distribution and elimination of 2,5,2',5'-tetrachloro[14C]biphenyl.(4-CB) were studied for 6 months after exposing sexually maturefemale yellow perch to the compound in water and transferringthem to flowing 4-CB-free water. Perch that were exposed inJanuary spawned in May, and the study was terminated in June.During the first 4 months after exposure, the t for whole-bodyelimination was 22 weeks, primarily by elimination of 4-CB fromthe viscera and carcass. During spawning, enhanced elimination(t < 0.7 weeks) was due to the voiding of eggs containing4-CB. After spawning, whole-body elimination returned to a slowerrate (t = 16.3 weeks). Prior to the enhancement in 4-CB eliminationrate during spawning, there was a redistribution of 4-CB residueswithin the body of the perch which was characterized by a transferof 4-CB residues from primarily the carcass and viscera to eggs.Two weeks after exposure, 30% of the initial 4-CB body burdenwas distributed to the eggs, whereas just prior to spawning,about 50% was present in this tissue. These findings demonstratethat egg maturation and spawning result in a significant reductionin the body burden of a persistent polychlorinated biphenylin a lean-fish species. 相似文献
86.
87.
JO Ezekwesili-Ofili NF Onyemelukwe P Agwaga I Orji 《African journal of traditional, complementary, and alternative medicines》2014,11(3):143-147
Background
There is increased reliance on traditional herbal medicines by several millions of people worldwide, especially in West Africa and Nigeria in particular. This is due to escalating cost of good quality drugs and consequent proliferation of faked cheaper drugs. However, non standardization of production and handling methods have resulted in herbal medicines with varying quality and safety indices, thus resulting in possible public health concerns. This work investigated the microbial load and aflatoxin levels in herbal medicines from selected states in Nigeria.Materials and Methods
A total of 210 samples obtained from various renowned herbal medicine practitioners from some selected states in Nigeria, based on their medicinal uses, were analyzed to determine the microbial load by the plate count method and aflatoxin contamination levels using thin layer chromatography with aflatoxin standards.Results
At least six bacterial genera (Bacillus, Pseudomonas, Salmonella, EPEC, EHEC, Streptococcus and other coliforms) and 6 fungal genera (Aspergillus, Penicillium, Rhizopus, Cladosporium, Geotricum and Candida) were isolated. Aflatoxin B1, B2 and G1 were detected in varying concentrations in the samples analyzed, with an average occurrence of 18.6%. Some of these herbal concoctions were found to contain unacceptably high bioload, according to WHO standards.Conclusion
Microbial contamination and the presence of aflatoxins in herbal medicines appear to be an endemic problem in Nigeria, as observed in this work, probably due to poor observation of basic hygiene during preparations and poor storage conditions. The findings in this work may serve in developing and instituting public health standards for the production and safety of herbal remedies in Nigeria. 相似文献88.
Pierre Feugier Deog-Yeon JO Jae Hung Shieh Karen L. MacKenzie JF Lesesve V Latger-Cannard D Bensoussan Ronald G Crystal Shahin Rafii JF Stoltz Malcolm A.S. Moore 《生物医学工程学杂志》2005,(Z1)
1 IntroductionCulture systems capable of expanding and/or maintaining hematopoietic stem cells will not only facilitate our understanding of stem cell biology, but also broaden clinical applications. Among various in vitro hematopoietic culture systems, co-cultures of marrow or CD34~ cells with an adherent stromal layer that can produce cytokines and extracellular matrix components most effectively supports long-term hematopoiesis (LTC), mimicking the bone marrow micro-environment.The OP-9 stromal cells ar... 相似文献
89.
90.
NORBERT M. van HEMEL M.D. JO J.A.M. DEFAUW M.D. GÉRARD M. GUIRAUDON M.D. JOHANNES C. KELDER M.D. EMILE R. JESSURUN M.D. JEF M.P.G. ERNST M.D. 《Journal of cardiovascular electrophysiology》1997,8(9):967-973
Late Results of Surgery for AF. Introduction: Currently, surgery- and catheter-mediated ablation is applied when drug refractoriness of atrial fibrillation is evident, although little is known about the long-term incidence of new atrial arrhythmia and the preservation of sinus node function.
Methods and Results: To address this issue, 30 patients with successful corridor surgery for lone paroxysmal atrial fibrillation and normal preoperative sinus node function were followed in a single outpatient department. Five years after surgery, the actuarial proportion of patients with recurrence of atrial fibrillation arising in the corridor was 8%± 5%, with new atrial arrhythmias consisting of atrial flutter and atrial tachycardia in the corridor 27%± 8%, and with incompetent sinus node requiring pacing therapy 13%± 6%. Right atrial transport was preserved in 69% of the patients without recurrence of atrial fibrillation and normal sinus node function. Stroke was documented in two patients.
Conclusions: Corridor surgery for atrial fibrillation is a transient or palliative treatment instead of a definitive therapy for drug refractory atrial fibrillation. This observation strongly affects patient selection for this intervention and constitutes a word of caution for other, non-pharmacologic interventions for drug refractory atrial fibrillation. 相似文献
Methods and Results: To address this issue, 30 patients with successful corridor surgery for lone paroxysmal atrial fibrillation and normal preoperative sinus node function were followed in a single outpatient department. Five years after surgery, the actuarial proportion of patients with recurrence of atrial fibrillation arising in the corridor was 8%± 5%, with new atrial arrhythmias consisting of atrial flutter and atrial tachycardia in the corridor 27%± 8%, and with incompetent sinus node requiring pacing therapy 13%± 6%. Right atrial transport was preserved in 69% of the patients without recurrence of atrial fibrillation and normal sinus node function. Stroke was documented in two patients.
Conclusions: Corridor surgery for atrial fibrillation is a transient or palliative treatment instead of a definitive therapy for drug refractory atrial fibrillation. This observation strongly affects patient selection for this intervention and constitutes a word of caution for other, non-pharmacologic interventions for drug refractory atrial fibrillation. 相似文献