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71.
This paper describes a teaching programme, for use in general practice vocational training, which provides a theoretical and practical framework for exploring key aspects of the consultation with trainees. A particular emphasis is on the educational or 'cognitive' outcomes of the consultation and skills for improving them. The five stages of the programme are described and an example of experience of each stage is given. The paper concludes with an evaluation of the programme by the trainers, trainees and social scientist involved.  相似文献   
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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   
75.
Swanson  DK; Myerowitz  PD; Hegge  JO; Watson  KM 《Radiology》1986,161(2):323-328
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   
76.
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   
77.
Bordin  JO; Heddle  NM; Blajchman  MA 《Blood》1994,84(6):1703-1721
A considerable literature has accumulated over the past decade indicating that leukocytes present in allogeneic cellular blood components, intended for transfusion, are associated with adverse effects to the recipient. These include the development of febrile transfusion reactions, graft-versus-host disease, alloimmunization to leukocyte antigens, and the immunomodulatory effects that might influence the prognosis of patients with a malignancy. Moreover, it has become evident that such leukocytes may be the vector of infectious agents such as CMV, HTLV-I/II, and EBV as well as other viruses. An interesting development that has occurred coincidentally in transfusion medicine is that agencies responsible for the provision of blood products are being designated manufacturers of biologicals. The trend among manufacturers of biologicals is to try to produce pure products to provide for the specific therapeutic need of patients. Thus, with the realization that allogeneic leukocytes and their products may have adverse biologic activities, there is increasing pressure from various sources for the reduction of the leukocyte content in allogeneic blood components to minimize the occurrence of their adverse effects. Although the threshold leukocyte number below which these effects might no longer occur is still to be determined, a 2 to 3 log10 leukocyte reduction, provided by the currently available commercial leukocyte filters, has been shown to reduce the frequency of many of such reactions. On the other hand, the immunosuppressive effects produced by the infusion of allogeneic leukocytes might be beneficial for some patients, ie, for the maintenance of kidney allografts, in possibly reducing the relapse rate in patients with inflammatory bowel diseases, and in ameliorating recurrent spontaneous abortion. Moreover, therapeutic granulocyte transfusions may be of benefit in certain well- defined categories of patients infected with bacteria, yeast, and/or fungi. These include neonates with bacterial sepsis associated with bone marrow failure as well as severely neutropenic leukemic patients with an infection unresponsive to appropriate and specific antibiotic therapy. Many of the results obtained with the use of leukocyte depletion filters are tantalizing, but the actual clinical benefit of leukodepletion has not been established in most instances, because much of the available data are retrospective or from uncontrolled clinical trials. Moreover, issues of cost-effectiveness and quality control have not been considered adequately. Properly designed prospective clinical trials are essential to provide data with which to answer such questions and also to help define the optimal conditions required for the preparation of blood components ultimately destined for clinical use. Only with the availability of such data can sound decisions be made about the clinical value of leukodepletion.  相似文献   
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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. 5,770–776. 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   
80.
We describe the chromosomal abnormalities found in 104 previously untreated patients with non-Hodgkin's lymphoma (NHL) and the correlations of these abnormalities with disease characteristics. The cytogenetic method used was a 24- to 48-hour culture, followed by G- banding. Several significant associations were discovered. A trisomy 3 was correlated with high-grade NHL. In the patients with an immunoblastic NHL, an abnormal chromosome no. 3 or 6 was found significantly more frequently. As previously described, a t(14;18) was significantly correlated with a follicular growth pattern. Abnormalities on chromosome no. 17 were correlated with a diffuse histology and a shorter survival. A shorter survival was also correlated with a +5, +6, +18, all abnormalities on chromosome no. 5, or involvement of breakpoint 14q11-12. In a multivariate analysis, these chromosomal abnormalities appeared to be independent prognostic factors and correlated with survival more strongly than any traditional prognostic variable. Patients with a t(11;14)(q13;q32) had an elevated lactate dehydrogenase (LDH). Skin infiltration was correlated with abnormalities on 2p. Abnormalities involving breakpoints 6q11-16 were correlated with B symptoms. Patients with abnormalities involving breakpoints 3q21-25 and 13q21-24 had more frequent bulky disease. The correlations of certain clinical findings with specific chromosomal abnormalities might help unveil the pathogenetic mechanisms of NHL and tailor treatment regimens.  相似文献   
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