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71.
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JENNIFER OCHERA SEAN HILTON J. MARTIN BLAND ANTHONY C. DOWELL DAVID R. JONES 《Journal of clinical nursing》1993,2(5):273-277
Summary
- ? The objective of this study was to describe the variation in provision of health checks and health-promotion clinics operating under the regulations of the 1990 Contract for general practice in the UK.
- ? Eighteen group practices in three Family Health Service Authority (FHSA) areas of England (two in the South West Thames region and one in the Yorkshire region) were selected for the study. The nurses, largely responsible for the implementation of the health checks at these practices, were interviewed using semi-structured interview schedules. They were asked about age-groups targeted, means of recruiting patients for clinics, duration of clinic appointments, and procedures carried out in clinics.
- ? All practices offered health checks, and 55% had started doing so before introduction of the 1990 Contract. Recruitment for health checks took place in a number of ways: self-referral (83% of practices); opportunistically in those with coronary heart disease risk factors (78%); opportunistically during attendance for cervical smears (62%); screening in at least one patient group (78%). Blood pressure, height, weight, urinalysis and life-style advice were included by all practices. Stress management and quit smoking strategies were offered only by a minority of practices. Duration of first health-check appointment ranged between 15 and 30 minutes.
- ? The basic content of health checks, and life-style advice given appeared consistent between the widely varying practices. However, the resources available for intervention and follow up showed more variation.
73.
KEYLER DANIEL E.; SALERNO DAVID M.; MURAKAMI MARYANN M.; RUTH GEORGE; PENTEL PAUL R. 《Toxicological sciences》1991,17(1):83-91
Rapid Administration of High-Dose Human Antibody Fab Fragmentsto Dogs: Pharmacokinetics and Toxicity. Keyler, D. E., Salerno,D. M., Murakami, M. M., Ruth, G., and Pentel, P. R. (1991).Fundam. Appl Toxicol 17, 83-91. The treatment of drug overdosewith drug-specific antibody fragments may require very highantibody doses. To address the feasibility of this therapy,we studied the pharmacokinetics and toxicity of high-dose humannonspecific Fab fragments in beagles. Three dogs received 5.3g/kg Fab iv over 1 hr. Because nephrotoxicity was observed,three subsequent dogs received 3.2 g/kg. The fraction of theFab dose excreted in urine (10 ± 6%%) was lower thanreported values for either high or low doses of Fab in otherspecies. The terminal serum elimination half-life (42 hr forthe higher and 48 hr for the lower dose) was also longer thanreported values for other species, due to lower renal and nonrenalFab clearance. Fab administration was tolerated without adversehemodynamic effects. One of three dogs at each dose developedtransient oliguria. All dogs developed a transient but markedincrease in the serum creatinine concentration. At 2 weeks creatinineclearance had returned to normal. Urinary protein and albuminexcretion at 2 weeks were within the normal range for dogs butwere increased over their baseline values. The histology ofall organs was normal at 3 weeks by light microscopy, and renalhistology by electron microscopy was also normal. The mechanismof Fab nephrotoxicity, not observed previously with high-doseFab in rats or lower doses of Fab in other species includingdogs, is not clear. These data suggest that further study ofthe potential toxicity of high-dose Fab, and its reversibility,is needed to assess the feasibility of treating drug overdosewith this antibody fragment The long terminal half-life of high-doseFab in the dog and its low renal clearance contrast with valuesobserved with lower doses of Fab in other species but wouldnot be expected to preclude the use of high-dose Fab for drugoverdose. 相似文献
74.
The Translocation of Inhaled Silicon Dioxide: An Empirically Derived Compartmental Model 总被引:1,自引:0,他引:1
VACEK PAMELA M.; HEMENWAY DAVID R.; ABSHER MARLENE P.; GOODWIN GREGORY D. 《Toxicological sciences》1991,17(3):614-626
The Translocation of Inhaled Silicon Dioxide: An EmpiricallyDerived Compartmental Model. VACEK, P. M., HEMENWAY, D. R.,ABSHER, M. P., AND GOODWIN, G. D. (1991). Fundam. Appl Toxicol.17, 614626. The movement of inhaled silicon dioxide particleswas studied by measuring the amounts in alveolar fluid and cells,lung tissue, and lymphoid tissue during the 6 months followingshort-term aerosol exposure of Fischer 344 rats. A variety offirst-order compartmental models were fit to data from nineexposure experiments to identify the most feasible biologicpathways for the transfer of material among these sites andout of the body. A multivariate least-squares approach was usedto simultaneously fit the data from several compartments. Theresults indicate that transfer between alveolar cells and lungtissue occurs in both directions, suggesting that silica canreenter the alveolar space from the lung tissue. This featurehas not been included in previously published models. The resultsalso indicate that transfer from lung tissue to the mediastinallymph nodes and thymus is indirect; there are one or more unidentifiedextrapulmonary compartments that receive silica from the lung.Rates of transfer among compartments were dependent on mineraltype (quartz or cristobalite), heat treatment, and exposuredose. There was no evidence for direct clearance from the alveolarspace via the tracheobronchial tract. 相似文献
75.
Triiodothyronine (T3 ) and Cardiovascular Therapeutics: A Review 总被引:1,自引:0,他引:1
DAVID R. SALTER M.D. CORNELIUS M. DYKE M.D. ANDREW S. WECHSLER M.D. 《Journal of cardiac surgery》1992,7(4):363-374
Hypothyroidism is associated with an abnormal hemodynamic state characterized by decreased heart rate, stroke volume, output, and contractility, and increased systemic vascular resistance. Since cardiopulmonary bypass (CPB) and surgical stress can induce profound decreases in triiodothyronine (T3) levels, the hemodynamic consequences of "stress-induced" hypothyroidism and T3 repletion are of increasing clinical interest. Available data generally support the likelihood of a beneficial effect associated with T3 replacement in brain-dead organ donors and in cases of low cardiac output following CPB. Although hypotheses have been advanced to account for these salutary effects, the mechanism by which T3 may augment hemodynamic performance has not been precisely defined, particularly in the acute setting. Although additional research is needed to clarify these and other issues, preliminary findings with T3 replacement indicate that such investigation is warranted. 相似文献
76.
SRINIVASAN RAJARAMAN SRIDHAR RAMAKRISHNAN DAVID THORSLEY NANCY J. WESENSTEN THOMAS J. BALKIN JAQUES REIFMAN 《Journal of sleep research》2012,21(6):659-674
We have developed a new psychomotor vigilance test (PVT) metric for quantifying the effects of sleep loss on performance impairment. The new metric quantifies performance impairment by estimating the probability density of response times (RTs) in a PVT session, and then considering deviations of the density relative to that of a baseline‐session density. Results from a controlled laboratory study involving 12 healthy adults subjected to 85 h of extended wakefulness, followed by 12 h of recovery sleep, revealed that the group performance variability based on the new metric remained relatively uniform throughout wakefulness. In contrast, the variability of PVT lapses, mean RT, median RT and (to a lesser extent) mean speed showed strong time‐of‐day effects, with the PVT lapse variability changing with time of day depending on the selected threshold. Our analysis suggests that the new metric captures more effectively the homeostatic and circadian process underlying sleep regulation than the other metrics, both directly in terms of larger effect sizes (4–61% larger) and indirectly through improved fits to the two‐process model (9–67% larger coefficient of determination). Although the trend of the mean speed results followed those of the new metric, we found that mean speed yields significantly smaller (~50%) intersubject performance variance than the other metrics. Based on these findings, and that the new metric considers performance changes based on the entire set of responses relative to a baseline, we conclude that it provides a number of potential advantages over the traditional PVT metrics. 相似文献
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80.
PREETHAM REDDY M.D. DAVID G. BENDITT M.D. SELCUK ADABAG M.D. M.S. 《Pacing and clinical electrophysiology : PACE》2012,35(3):e52-e54
An electromagnetic interaction between St. Jude Medical Inc. (St. Paul, MN, USA) permanent pacemakers and HeartMate II left ventricular assist devices (LVADs) (Thoratec Inc., Pleasanton, CA, USA) has been reported before, but the problem was thought to be resolved in the St. Jude Medical's most recently released pacemaker platform. We report a case of interference between the HeartMate II LVAD and the most recently released St. Jude Medical pacemaker (model no. PM3210; Anthem) and review new developments to overcome the electromagnetic interference problem in this setting. (PACE 2010; 1–3) 相似文献