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991.
The regional dialects or regiolects of the Rufous-collared Sparrow Zonotrichia capensis were compared between Campinas (47 degrees 06'W-22 degrees 90'S) and Botucatu (48 degrees 44'W-22 degrees 88'S), S?o Paulo State, Southeastern Brazil. Songs of 88 individuals from thirteen localities were recorded. Sonograms showed that two areas presented more homogeneous songs, forming two regiolects. In 11 localities most individuals shared the same song type. At the other two localities, they sang up to 5 different song types. This occurs at the boundaries of the regiolects, and was also where individuals singing more than one song type were found. Similarities between song types were not related to geographic distance between the respective singers. A comparative analysis showed similarities in these regiolects with song of populations from Northeastern Brazil. 相似文献
992.
Chelly JE Grass J Houseman TW Minkowitz H Pue A 《Anesthesia and analgesia》2004,98(2):427-33, table of contents
A noninvasive method of delivery of parenteral opioids for management of acute pain may offer logistic advantages for patients and nursing staff. A patient-controlled transdermal system (PCTS) under development consists of a preprogrammed, self-contained drug-delivery system that uses electrotransport technology (E-TRANS, ALZA Corp, Mountain View, CA) to deliver 40 micro g of fentanyl HCl over 10 min per on-demand dose for patient-controlled analgesia (PCA). In this randomized, double-blinded, placebo-controlled trial we compared the efficacy and safety of on-demand fentanyl HCl PCTS 40 microg against placebo for postoperative pain up to 24 h after major abdominal, orthopedic, or thoracic surgery in 205 patients. The primary efficacy measurement was the percentage of patients withdrawn from the study because of inadequate analgesia after completing at least 3 h of treatment. Secondary efficacy measures included mean pain intensity (using visual analog scales), patient global assessments, and investigator global assessments. Of 189 patients considered evaluable for efficacy, 25% of patients in the fentanyl HCl PCTS 40 microg group withdrew because of inadequate analgesia, compared with 40.4% of the placebo group (P < 0.05). Use of fentanyl HCl PCTS 40 micro g was associated with lower VAS scores and higher mean patient and investigator global assessment scores compared with placebo. No patient experienced clinically relevant respiratory depression. This study showed that a fentanyl HCl PCTS 40 microg for PCA was superior to placebo and well tolerated for the control of moderate to severe postoperative pain for up to 24 h after major surgery. IMPLICATIONS: This multicenter, randomized, double-blinded, placebo-controlled trial showed that an on-demand fentanyl HCl patient-controlled transdermal system (PCTS) was superior to placebo and well tolerated for the control of moderate to severe postoperative pain for up to 24 h after major surgery. This fentanyl HCl PCTS is a preprogrammed, needle free, self-contained drug-delivery system that uses electrotransport technology (iontophoresis) to deliver 40 microg of fentanyl per on-demand dose. 相似文献
993.
Ventricular septal defect (VSD) closure is an important part of the surgical repair of tetralogy of Fallot and related anomalies. Visual appreciation of the VSD size (either transinfundibular or transatrial) can be misleading. My colleagues and I describe a simple and precise way to predict the size and shape of the VSD patch before extracorporeal circulation: the patch should be circular with a diameter identical to that of the mid ascending aorta. 相似文献
994.
Tan EC Rieu PN Nijveld A Backx AP Meis JF Severijnen RS 《The Annals of thoracic surgery》2004,78(3):1086-1088
Pericarditis as a complication of appendicitis is a rare event. In a 25-year period we encountered two pediatric cases with this severe complication due to (a)typical presentation of appendicitis resulting in small bowel obstruction, intraabdominal abscesses, constrictive pericarditis, and purulent pericarditis. 相似文献
995.
Costi R Himpens J Iusco D Sarli L Violi V Roncoroni L Cadière GB 《Chirurgia italiana》2004,56(3):321-331
Presented as a possible "second" revolution in general surgery after the introduction of laparoscopy during the last few years, the robotic approach to mini-invasive surgery has not yet witnessed wide, large-scale diffusion among general surgeons and is still considered an "experimental approach". In general surgery, the laparoscopic treatment of gastrooesophageal reflux is the second most frequently performed robot-assisted procedure after cholecystectomy. A review of the literature and an analysis of the costs may allow a preliminary evaluation of the pros and cons of robotic fundoplication, which may then be applicable to other general surgery procedures. Eleven articles report 91 cases of robotic fundoplication (75 Nissen, 9 Thal, 7 Toupet). To date, there is no evidence of benefit in terms of duration of surgery, rate of complications and hospital stay. Moreover, robotic fundoplication is more expensive than the traditional laparoscopic approach (the additional cost per procedure due to robotics is 1,882.97 euros). Only further technological upgrades and advances will make the use of robotics competitive in general surgery. The development of multi-functional instruments and of tactile feedback at the console, enlargement of the three-dimensional laparoscopic view and specific "team" training will enable the use of robotic surgery to be extended to increasingly difficult procedures and to non-specialised environments. 相似文献
996.
997.
Screening decreases prostate cancer mortality: 11-year follow-up of the 1988 Quebec prospective randomized controlled trial 总被引:7,自引:0,他引:7
Labrie F Candas B Cusan L Gomez JL Bélanger A Brousseau G Chevrette E Lévesque J 《The Prostate》2004,59(3):311-318
PURPOSE: This clinical trial is aimed at evaluating the impact of prostate cancer screening on cancer-specific mortality. SUBJECTS AND METHODS: Forty-six thousand four hundred and eighty-six (46,486) men aged 45-80 years registered in the electoral roll of the Quebec city area were randomized in 1988 between screening and no screening. Screening included measurement of serum prostatic specific antigen (PSA) using 3.0 ng/ml as upper limit of normal and digital rectal examination (DRE) at first visit. At follow-up visits, serum PSA only was used. RESULTS: Seventy-four (74) deaths from prostate cancer occurred in the 14,231 unscreened controls while 10 deaths were observed in the screened group of 7,348 men during the first 11 years following randomization. Median follow-up of screened men was 7.93 years. A Cox proportional hazards model of the age at death from prostate cancer shows a 62% reduction (P < 0.002, Fisher's exact test) of cause-specific mortality in the screened men (P = 0.005). These results are in agreement with the continuous decrease of prostate cancer mortality observed in North America. 相似文献
998.
Endovascular treatment of anterior choroidal artery aneurysms 总被引:1,自引:0,他引:1
Piotin M Mounayer C Spelle L Williams MT Moret J 《AJNR. American journal of neuroradiology》2004,25(2):314-318
BACKGROUND AND PURPOSE: Ischemic stroke is the most common complication after surgical clipping of anterior choroidal artery (AChA) aneurysms, and the reported morbidity-mortality rates vary from 5% to 50%. We report the findings in a series of 18 consecutive patients who underwent endovascular treatment (EVT) for an AChA berry aneurysm. METHODS: In this retrospective study, the aneurysms were defined according to their size and position, the presence of a concomitant arteriovenous malformation (AVM), the mode of presentation. The patients were clinically assessed before and after the EVT, as well as at each angiographic follow-up. RESULTS: All were small-sized aneurysms, with greater diameters ranging from 2 to 8 mm (mean, 4 mm), arising from the supraclinoid internal carotid artery close to the origin of the AChA. Two were AVM-associated aneurysms. Fourteen patients (14/18 [78%]) presented with subarachnoid hemorrhage. All aneurysms were selectively embolized with coils. There was one (1/18 [5.5%]) treatment-related death due to aneurysm perforation. Another patient (1/18 [5.5%]) developed a transient controlateral hemiparesis. Fourteen patients (14/18 [78%]) were followed up clinically and angiographically for 3-32 months (mean, 14 months). None of them (re)hemorrhaged during this period. CONCLUSION: The EVT of AChA berry aneurysms is effective to protect from rebleeding. Our complication rate compares favorably with those of the surgical series. 相似文献
999.
Koppo K Wilkerson DP Bouckaert J Wilmshurst S Campbell IT Jones AM 《Medicine and science in sports and exercise》2004,36(7):1159-1164
PURPOSE: To test the hypothesis that pharmacological activation of the pyruvate dehydrogenase enzyme complex (PDC) with dichloroacetate (DCA) would speed phase II pulmonary oxygen uptake ((.-)V(O2)) kinetics after the onset of subsequent moderate-intensity (40-45% ((.-)V(O2)) peak) cycle exercise. METHODS: Seven healthy males (mean +/- SD age 25 +/- 4 yr, body mass 75.3 +/- 9.4 kg) performed four "square-wave" transitions from unloaded cycling to a work rate requiring 90% of the predetermined gas exchange threshold either with or without prior infusion of DCA (50 mg x kg body mass in 50 mL saline). Pulmonary ((.-)V(O2)) was measured breath-by-breath in all tests and ((.-)V(O2)) kinetics were determined from the averaged individual response to each condition using nonlinear regression techniques. RESULTS: The blood [lactate] measured immediately before the onset of exercise was significantly reduced in the DCA condition (C: 1.1 +/- 0.3 vs DCA: 0.6 +/- 0.3 mM; P < 0.01) consistent with successful activation of the PDC. However, DCA had no discernible effect on the rate at which ((.-)V(O2)) increased toward the steady state after the onset of exercise as reflected in the phase II time constant (C: 28.5 +/- 11.8 vs DCA: 29.4 +/- 14.9 s). CONCLUSIONS: The results suggest that PDC activation does not represent a principal intramuscular limitation to ((.-)V(O2)) kinetics after the onset of moderate-intensity exercise. 相似文献
1000.
Effect of ski binding parameters on knee biomechanics: a three-dimensional computational study 总被引:2,自引:0,他引:2
St-Onge N Chevalier Y Hagemeister N Van De Putte M De Guise J 《Medicine and science in sports and exercise》2004,36(7):1218-1225
INTRODUCTION: Downhill skiing is a relatively safe sport, but many potentially avoidable injuries do occur. Whereas tibia and ankle injuries have been declining, severe knee sprains usually involving the anterior cruciate ligament (ACL) have increased from the 1970s to the 1990s. The goal of the present study was to evaluate the effect of the position of the binding pivot point and binding release characteristics on ACL strain during a phantom-foot fall. METHODS: We computed ACL strain using a biomechanical computer knee model to simulate the phantom-foot ACL-injury mechanism. This mechanism, which is one of the most common mechanisms of ACL injury in downhill skiing, occurs when the weight of the skier is on the inner edge of the ski during a backward fall, resulting in a sharp uncontrolled inward turn of the ski. RESULTS: The model predicts, that under simulated phantom-foot conditions, a binding with fast-release characteristics with a pivot positioned in front of the center of the boot produces less strain on the ACL. Current bindings have their pivot point approximately at the center of the heel radius. A pivot positioned at the back of the binding is more effective for sensing loads that occur at the tip of the ski. However, it is less effective for sensing loads that occur at the tail of the ski and, therefore, offers less protection during a phantom-foot fall. CONCLUSION: A binding with two pivot points, one positioned in front and the other at the back, could sense twist loads applied to the ski both at the front and at the back, and might, therefore, be a solution to reduce the occurrence of ACL injuries. 相似文献