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991.
Aneurysm of the ductus arteriosus is a rare diagnosis, with most cases found in the pediatric population. The unusual adult cases reported in the literature have been associated with high morbidity and a surgical repair has been recommended. We report a case of a 60-year-old man who presented with hoarseness secondary to a ductus arteriosus aneurysm and underwent a repair of this abnormality via a left posterolateral thoracotomy utilizing partial cardiopulmonary bypass. 相似文献
992.
Tibial Angioplasty as an Alternative Strategy in Patients with Limb-Threatening Ischemia 总被引:3,自引:0,他引:3
Clair DG Dayal R Faries PL Bernheim J Nowygrod R Lantis JC Beavers FP Kent KC 《Annals of vascular surgery》2005,19(1):63-68
The purpose of this study was to assess the technical feasibility and early outcome of tibial angioplasty for a subset of patients with limb-threatening ischemia who were not candidates for bypass grafting. A retrospective analysis was conducted of 19 patients (7 male, 12 female) who underwent crural angioplasty for limb-threatening ischemia using 0.018- or 0.014 inch-based systems. Contraindications to bypass were insufficient conduit in 7 patients and severe comorbid illness in 12. Concurrent treatment of inflow lesions was performed in 12 of 20 limbs via either angioplasty alone (5) or combined with stenting (12). Outcome measures were anklebrachial indices (ABI), relief of rest pain, and healing or healed wounds. Twenty-three vessels were treated, including 14 tibial occlusions and 9 stenoses. The average length of diseased segment was 11 cm (range, 3-25 cm). Thirteen of 14 occlusions were treated with subintimal recanalization, the remainder with laser recanalization. Technical success was achieved in 22 of 23 treated vessels. Mean preoperative ABI was 0.53 and mean postoperative ABI was 0.85. Palpable pulses were present in 11 of 20 limbs (55%). There was one perioperative mortality (5.2%). Mean follow-up was 3 months. Three failures occurred requiring amputation (15.8%). The remaining 16 patients were improved with healing (8) or healed (4) wounds and relief of rest pain (4). These results indicate that technical success may be achieved with outflow lesion angioplasty in the majority of patients encountered. The durability of this method of therapy is unknown, and our length of follow-up is not sufficient to answer this question. However, an attempt at angioplasty appears justified before primary amputation and before surgical bypass in those patients at high risk for intervention.Presented at the 17th Annual Meeting of the Eastern Vascular Society, New York, NY, May 1-5, 2003. 相似文献
993.
994.
We compare the more common physician compensation method of fee-for-service to the less common payment-for-outcomes method. This paper combines an investigation of the theoretical properties of both of these payment regimes with a unique data set from rural Cameroon in which patients can choose between outcome and service based payments. We show that consideration of the role of patient effort in the production of health leads to important differences in the performance of these contracts. Theory and empirical evidence show that when illnesses require (or are responsive to) large amounts of both patient and practitioner effort, outcome based payment schemes are superior to effort based schemes. The traditional healer--a practitioner who offers health services on an outcome-contingent basis--is advanced as an important example of how patient effort can be better understood and tapped in health care. 相似文献
995.
Karen H. Seal Robert Thawley Lauren Gee Joshua Bamberger Alex H. Kral Dan Ciccarone Moher Downing Brian R. Edlin 《Journal of urban health》2005,82(2):303-311
Fatal heroin overdose has become a leading cause of death among injection drug users (IDUs). Several recent feasibility studies
have concluded that naloxone distribution programs for heroin injectors should be implemented to decrease heroin overdose
deaths, but there have been no prospective trials of such programs in North America. This pilot study was undertaken to investigate
the safety and feasibility of training injection drug using partners to perform cardiopulmonary resuscitation (CPR) and administer
naloxone in the event of heroin overdose. During May and June 2001, 24 IDUs (12 pairs of injection partners) were recruited
from street settings in San Francisco. Participants took part in 8-hour training in heroin overdose prevention, CPR, and the
use of naloxone. Following the intervention, participants were prospectively followed for 6 months to determine the number
and outcomes of witnessed heroin overdoses, outcomes of participant interventions, and changes in participants’ knowledge
of overdose and drug use behavior. Study participants witnessed 20 heroin overdose events during 6 months follow-up. They
performed CPR in 16 (80%) events, administered naloxone in 15 (75%) and did one or the other in 19 (95%). All overdose victims
survived. Knowledge about heroin overdose management increased, whereas heroin use decreased. IDUs can be trained to respond
to heroin overdose emergencies by performing CPR and administering naloxone. Future research is needed to evaluate the effectiveness
of this peer intervention to prevent fatal heroin overdose. 相似文献
996.
997.
Association between phonocardiographic third and fourth heart sounds and objective measures of left ventricular function 总被引:3,自引:0,他引:3
Marcus GM Gerber IL McKeown BH Vessey JC Jordan MV Huddleston M McCulloch CE Foster E Chatterjee K Michaels AD 《JAMA》2005,293(18):2238-2244
Context The third (S3) and fourth (S4) heart sounds detected by phonocardiography are considered to represent the criterion standards of the gallop sounds, but their test characteristics have not been explored. Objective To determine the diagnostic test characteristics of the S3 and S4 for prediction of left ventricular dysfunction using a computerized heart sound detection algorithm. Design, Setting, and Participants Prospective study of 90 adult patients undergoing elective left-sided heart catheterization at a single US teaching hospital between August 2003 and June 2004. The mean age was 62 (SD, 13) years (range, 24-90 years) and 61 (68%) were male. Within a 4-hour period, participants underwent computerized heart sound phonocardiographic analysis, cardiac catheterization, transthoracic echocardiography, and blood sampling for assessment of an S3/S4, left ventricular end-diastolic pressure (LVEDP), left ventricular ejection fraction (LVEF), and B-type natriuretic peptide (BNP), respectively. Main Outcome Measures Diagnostic test characteristics of the computerized phonocardiographic S3 and S4 using markers of left ventricular function as criterion standards. Results Mean (SD) LVEDP was significantly elevated (18.4 [6.9] mm Hg vs 12.1 [7.3] mm Hg; P<.001), mean (SD) LVEF was reduced (49.4% [20.2%] vs 63.6% [14.8%]; P<.001), and median (interquartile range) BNP was elevated (330 [98-1155] pg/mL vs 86 [41-192] pg/mL; P<.001) in those with an S3, S4, or both compared with patients without a diastolic heart sound. The sensitivities of these heart sounds to detect an elevated LVEDP, reduced LVEF, or elevated BNP were 41%, 52%, and 32% for an S3, and 46%, 43%, and 40% for an S4, respectively. For abnormal levels of the same markers of ventricular function, the specificities of the S3 were 92%, 87%, and 92%, while the specificities of the S4 were 80%, 72%, and 78%, respectively. Conclusions Neither the phonocardiographic S3 nor the S4 is a sensitive marker of left ventricular dysfunction. The phonocardiographic S3 is specific for left ventricular dysfunction and appears to be superior to the moderate specificity of the phonocardiographic S4. 相似文献
998.
999.
1000.
Crozier SJ Kimball SR Emmert SW Anthony JC Jefferson LS 《The Journal of nutrition》2005,135(3):376-382
Oral administration of a single bolus of leucine in an amount equivalent to the daily intake (1.35 g/kg body wt) enhances skeletal muscle protein synthesis in food-deprived rats. To elucidate whether smaller amounts of leucine can also stimulate protein synthesis, rats were administered the amino acid at concentrations ranging from 0.068 to 1.35 g/kg body wt by oral gavage. Thirty minutes following the administration of doses of leucine as low as 0.135 g/kg body wt, skeletal muscle protein synthesis was significantly greater than control values. The increase in protein synthesis was associated with changes in the regulation of biomarkers of mRNA translation initiation as evidenced by upregulated phosphorylation of the translational repressor, eukaryotic initiation factor (eIF)4E-binding protein 1 (4E-BP1), the association of eIF4G with the mRNA cap binding protein eIF4E, and the phosphorylation of the 70-kDa ribosomal protein S6 kinase. Alterations in the phosphorylation of eIF4G, as well as the association of 4E-BP1 with eIF4E, were observed following leucine administration; however, these changes appeared to be biphasic with maximal changes occurring when circulating insulin concentrations were elevated. Thus it appears that leucine administration affects mRNA translation and skeletal muscle protein synthesis through modulation of multiple biomarkers of mRNA translation. The ability of small doses of leucine to stimulate skeletal muscle protein synthesis suggests that future research on the regulation of skeletal muscle protein synthesis by orally administered leucine will be feasible in humans. 相似文献