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Background: Bupivacaine retards myocardial acidosis during ischemia. The authors measured function of rat isolated hearts after prolonged storage to determine whether bupivacaine improves cardiac protection compared with standard cardioplegia alone.

Methods: After measuring cardiac function on a Langendorff apparatus, hearts were perfused with cardioplegia alone (controls), cardioplegia containing 500 [mu]m bupivacaine, or cardioplegia containing 2 mm lidocaine; were stored at 4[degrees]C for 12 h; and were then reperfused. Heart rate and left ventricular developed pressures were measured for 60 min. Maximum positive rate of change in ventricular pressure, oxygen consumption, and lactate dehydrogenase release were also measured.

Results: All bupivacaine-treated, four of five lidocaine-treated, and no control hearts beat throughout the 60-min recovery period. Mean values of heart rate, left ventricular developed pressure, maximum positive rate of change in ventricular pressure, rate-pressure product, and efficiency in bupivacaine-treated hearts exceeded those of the control group (P < 0.001 at 60 min for all). Mean values of the lidocaine group were intermediate. Oxygen consumption of the control group exceeded the other groups early in recovery, but not at later times. Lactate dehydrogenase release from the bupivacaine group was less than that from the control group (P < 0.001) but did not differ from baseline.  相似文献   

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The effect of nine obstacles on family physicians' screening practices is reported. Family physicians, responding to a survey of periodic health screening practices, were asked to check the obstacles that affected their use of the screening tests listed. In the survey, 129 members of the American Academy of Family Physicians and 146 members of the Society of Teachers of Family Medicine responded. The most frequently reported obstacles to screening were cost to the patient, patient refusal, inconvenience to the patient, and lack of facilities or equipment. The tests for which the most obstacles were reported were sigmoidoscopy, tonometry, and mammography. The Society of Teachers of Family Medicine physicians were more likely to list cost, patient reluctance, inconvenience to the patient, "the literature does not recommend to use the test," time to perform the tests, and high rate of false positives and negatives. American Academy of Family physicians were more likely to report two obstacles, lack of facilities or equipment and risk to the patient. An analysis of the relationship between obstacle report and test utilization indicated that for only five of the nine obstacles were physicians who listed the obstacle less likely to use the test than physicians who did not list the obstacle. Obstacles related with decreased test use were those that affected the physician's ability to perform the test or the efficacy of the test itself while "inactive" obstacles were those that more directly affected and emanated from patients.  相似文献   
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<正>To the Editor:Ischemia-reperfusion injury following surgery and transplantation can lead to irreversible multiorgan failure.Intracellular calcium overload is associated to cellular death during ischemiareperfusion.A recently discovered heparin fragment (HF),trisulfated disaccharide (TD),that acts on sodium-calcium exchanger(NCX) decreasing intracellular Ca2+,showed effectiveness on protecting hepatocytes from ischemia-reperfusion injury [1],  相似文献   
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Surgical treatment of patients with congestive heart failure (CHF) has steadily advanced from rescue procedures such as aneurysmectomy, rupture repair, ventricular assist devices (VADs), and transplantation to procedures that can prevent or delay the progression of cardiac dysfunction and failure. The latter include operations such as coronary artery bypass grafting (CABG) and mitral valve repair for patients with ischemic cardiomyopathy (ICMP) and mitral annular dilatation, ventricular restoration and remodeling, and cardiac resynchronization therapy. As the number of heart transplants reported worldwide continues to decline over the past decade (by over 30%), newer surgical therapies have emerged. A need arises for clinical registries such as the NIH-sponsored LVAD registry and registries for biventricular pacing and AICD implantation, for total artificial heart implants, and for mitral valve repair in patients with ICMP. Prospective trials comparing sole ventricular restoration therapy (SVR) to SVR with concomitant CABG/MVR, coronary sinus versus epicardial LV pacing for ventricular resynchronization therapy, trials comparing LVAD as destination therapy to AICD implants, mitral valve repair versus chordal-sparing valve replacement for ischemic and valvular cardiomyopathy, and off-pump versus on-pump CABG for patients with ICMP are urgently needed. Future research should also be directed toward drugs targeting “B-cell mediated” humeral vascular rejection—the Achilles heel of cardiac transplantation, xenotransplantation, permanently implantable VADs, gene therapy, and myocardial cell regeneration therapy.  相似文献   
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PURPOSE: We determined whether radiographic evaluation is indicated in all children with traumatic hematuria. MATERIALS AND METHODS: We retrospectively reviewed the records of 110 children from 1992 to 1999 diagnosed with blunt trauma and hematuria. It is routine practice at our emergency department to perform radiographic evaluation in all children with hematuria regardless of the degree. Each chart was evaluated for the mechanism of injury, degree of hematuria, hypotension, imaging studies, renal injury, renal anomalies, associated injuries and outcome. RESULTS: A total of 110 patients 1 to 18 years old (mean age 9) were identified. The most common mechanism of injury was motor vehicle accident in 37 children (34%), followed by a fall in 32 (29%). Grades I to V renal injury was present in 5, 6, 6, 6 and 1 cases, respectively (22%), while 1 (0.9%) involved ureteropelvic junction avulsion. No child had renal pedicle injury. In 9 patients renal anomalies were detected incidentally. Of the 110 patients 101 underwent radiographic evaluation, including computerized tomography in 97 (88%). The 24 patients (22%) with significant renal injury and all with incidentally diagnosed renal anomalies had 50 or greater red blood cells per high power field on urinalysis, while 1 with ureteropelvic junction avulsion presented without hematuria. Hypotension was present in only 3 patients (2.7%), who also had associated injuries, including 2 who presented with renal injury. All 3 with associated injuries. Associated injuries were identified in 11 of 25 patients (44%). The 9 patients (8%) who did not undergo radiographic imaging had negative results on repeat urinalysis with an excellent outcome. CONCLUSIONS: We recommend that radiological evaluation consisting of abdominal and pelvic computerized tomography should be performed only in patients with 50 or greater red blood cells on urinalysis, hypotension at presentation to the emergency room or based on the severity of mechanism of injury, for example high speed motor vehicle accident deceleration injuries. The patient who presented with ureteropelvic junction avulsion without hematuria would have undergone imaging considering the mechanism of injury and number of associated injuries.  相似文献   
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