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1.
D Mellière D Berrahal P Desgranges E Allaire JP Becquemin 《Canadian Metallurgical Quarterly》1998,23(5):342-348
The purpose of this study was to compare the physiological responses of professional and elite road cyclists during an incremental cycle ergometer test. Twenty-five elite cyclists (EC; 23+/-1 yr) and 25 professional cyclists (PC; 25+/-2yr) performed a ramp protocol (increases of 25 W x min(-1)) during which the following parameters were measured: oxygen consumption (VO2), pulmonary ventilation (VE), ventilatory equivalents for oxygen and carbon dioxide (VE x VO2(-1) and VE x VCO2(-1), respectively), respiratory exchange ratio (RER), ventilatory thresholds 1 and 2 (VT1 and VT2, respectively), blood lactate, and electromyographic activity (EMG) of the vastus lateralis. Significant differences existed between the two groups mainly at submaximal intensities, since both VT1 and VT2 occurred at a higher exercise intensity (p<0.001) in PC than in EC (VT2: 80.4+/-6.6 vs 87.0+/- 5.9% VO2max in EC and PC, respectively). Lactate levels showed a similar response in both groups at low-to-moderate intensities (< 300 W), and thereafter blood lactate was significantly higher in EC. Finally, the "electromyographic threshold" (EMGT) occurred at a significantly higher intensity (p < 0.05) in PC when compared to EC (64.7+/-14.2 vs 56.0+/-14.9% VO2max, respectively). It was concluded that, in comparison with EC, PC exhibit some remarkable physiological characteristics such as a high VT2, an important reliance on fat metabolism even at high power outputs, and several neuromuscular adaptations. 相似文献
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E HOLMAN 《Canadian Metallurgical Quarterly》1955,100(5):599-611
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GJ Collins NM Rich J Philllips RW Hobson CA Andersen 《Canadian Metallurgical Quarterly》1976,42(11):853-858
"B" mode ultrasound scanning is useful in the diagnosis of popliteal arterial aneurysms. It offers advantages over physical examination and arteriography, since these aneurysms are sometimes difficult to palpate and may be partially filled with laminated clot. The technique is noninvasive and without known hazard in this location. "B" mode ultrasound scanning promises to be useful in the diagnosis of aneurysms of other extremity arteries. It has already been useful in confirming the presence of femoral false aneurysms. Greater familiarity with the technique and improvepd technology will result in even greater reliance on ultrasound diagnosis. 相似文献
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WM Tang JS Pulido TB Connor P Sternberg MF Lewandowski 《Canadian Metallurgical Quarterly》1998,18(6):559-563
BACKGROUND AND STUDY AIMS: Caroli's disease causes relapsing episodes of cholangitis due to the presence of intrahepatic lithiasis. Strategies for cholangitis prevention are still widely debated. Ursodeoxycholic acid, hepaticojejunostomy, partial hepatectomy, or transplantation, have all been proposed as therapeutic options. The aim of this study was to evaluate the role of therapeutic endoscopy, and especially endoscopic sphincterotomy (ES), in the management of Caroli's disease. PATIENTS AND METHODS: Between 1983 and 1995, six patients with Caroli's disease (mean age 52, range 17-75) underwent endoscopic retrograde cholangiopancreatography (ERCP) for acute cholangitis. Sphincterotomy was performed if common bile duct stones were present. Extracorporeal shock-wave lithotripsy, (ESWL) or intraductal electrohydraulic lithotripsy (IEL) were performed if necessary. RESULTS: The mean number of endoscopic sessions per patient was four (range three to seven). Sphincterotomy was performed in five patients and cholangioscopy in three. ESWL was performed twice in each of four patients. A Strecker expandable metal stent was placed in one patient to maintain sphincterotomy patency. In one patient, two sessions of IEL and pulsed laser were carried out. Complete clearance of intrahepatic stones was achieved in four of the six subjects (66.6%) and partial clearance in two patients. No morbidity or mortality was observed. During the follow-up (mean 6.2 years; range: 2.1-16.3), only two patients had acute cholangitis at nine months and three years, respectively, after the endoscopic treatment. Both had residual intrahepatic stones left after the initial endoscopic attempt at clearance. CONCLUSION: ERCP is a necessary diagnostic procedure which should always be carried out in patients with Caroli's disease. Our experience shows that ES does not result in an increased incidence of cholangitis and that therapeutic endoscopy allows complete clearance of intrahepatic stones in the majority of patients with unresectable symptomatic Caroli's disease. Nevertheless, the oncological risk in these patients remains unchanged, and they still have an increased risk of cholangiocarcinoma. 相似文献
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PA Christensen E Tvedegaard S Strandgaard BS Thomsen 《Canadian Metallurgical Quarterly》1997,26(5):386-388
A study was made of the incidence and predisposing factors in non-surgical infections in a group of 159 patients undergoing oncological head and neck surgery. The incidence of these infections was 5.7%; the most frequent was lung infection (3.8%), followed by septic phlebitis (1.3%) and urinary infection (0.6%). Risk factors for pulmonary infection included advanced tumor stage, prolonged surgery, and supraglottic laryngectomy. No relationship was found with age, previous illnesses, tumor site, or the antibiotic used in preoperative prophylaxis. 相似文献
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TS Chang GW Aylward JL Davis WF Mieler GL Oliver AL Maberley JD Gass 《Canadian Metallurgical Quarterly》1995,102(7):1089-1097
PURPOSE: The authors describe the clinical feature of ten patients with a new syndrome characterized by the presence of retinal vasculitis, multiple macroaneurysms, neuro-retinitis, and peripheral capillary nonperfusion. METHODS: The authors evaluated ten patients identified to have clinical features compatible with the syndrome of idiopathic retinal vasculitis, aneurysms and neuroretinits (IRVAN). Clinical examination findings, sequential funds photographs (when available), fluorescein angiograms, systemic investigations, response to therapy, and visual outcomes were reviewed. RESULTS: Seven eyes of four patients sustained a marked decrease in visual acuity of 20/200 or worse. Visual loss was due to a combination of an exudative maculopathy and sequelae of retinal ischemia. Capillary nonperfusion was seen in all ten patients and was severe enough to warrant panretinal laser photocoagulation in six patients. Systemic investigations were uniformly noncontributory. Oral prednisone appears to have little beneficial effects on patients with this disorder. CONCLUSIONS: Patients with IRVAN have characteristic retinal features that readily identify this syndrome. An increased awareness of this rare syndrome may help to identify sight-threatening complications at an earlier stage. The authors caution against extensive medical investigations. 相似文献
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V Halpern J O'Connor M Murello D Siegel JR Cohen 《Canadian Metallurgical Quarterly》1997,25(5):949-956
A 6-year-old boy from China presented initially at 2 years of age with a pulsatile mass in his right antecubital fossa. He was not fully evaluated until the age of six years, when pan-angiography and computed axial tomography scan revealed multiple aneurysms of his right brachial artery, right radial artery aneurysms, an infrarenal aortic aneurysm, and a right internal carotid artery aneurysm in the region of the cavernous sinus. The patient underwent uneventful repairs of both the abdominal aortic aneurysm and the multiple aneurysms of the right arm. Pathologic evaluation was significant for medial fibrosis of the arterial wall with decreased and disordered elastin fibers. Review of the previously reported cases in children indicate the upper extremity arteries are involved in 92% of patients, the aortoiliac region in 92% of patients, and the renal/mesenteric vessels in 77% of cases. Lower extremity and cerebrovascular arteries are involved to a lesser extent. Children with peripheral aneurysms should have pan-angiography performed before treatment is begun. Surgical repair in these cases has been excellent. 相似文献
11.
MR angiography provides a rapid, accurate, and extremely flexible noninvasive evaluation of intracranial aneurysms without the cost and risk of conventional angiography. TOF and phase contrast techniques each have specific advantages and disadvantages that can be selectively exploited to optimize aneurysm evaluation. Present indications for MR angiography in aneurysm evaluation include: (1) the presence of incidental findings on a CT or MR examination that suggest the possibility of aneurysm (Figs. 7 and 8), (2) when angiography is contraindicated or when the risk is too high, (3) non-invasive follow-up of patients with known aneurysms, (4) patient refusal of contrast angiography, and (5) evaluation of patients with specific clinical symptoms (i.e., third cranial nerve palsy) or patients with non-specific subacute symptoms in whom an aneurysm might explain the clinical presentation. Although MR angiography certainly can detect aneurysms with a high rate of sensitivity and specificity, detailed decision analyses generally have not supported the overall benefit of this type of screening. Future technical advances as well as advances in the overall understanding of aneurysms may one day prove unequivocally the benefit of MR angiography in screening high-risk patient groups. MR angiography has not yet been clinically evaluated as a tool in the evaluation of acute subarachnoid hemorrhage. Potential obstacles to such an evaluation include the clinical instability of SAH patients, limited spatial resolution of the MR angiography acquisitions, the potential for subarachnoid blood or focal intraparenchymal hematomas to obscure or mimic small aneurysms, and the unreliability of MR angiography in demonstrating vasospasm. Currently these factors continue to provide an integral role for contrast angiography in aneurysm evaluation. 相似文献
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T Suchy 《Canadian Metallurgical Quarterly》1995,74(6):284-286
Venous aneurysms are a rare condition. It is an independent nosological unit which differs from varicosities by the following signs: it is not sex- or age-linked, it is found also in children, it can affect any vein, it is found as a solitary lesion and is not associated with prolongation of the affected vein. The therapeutic approach is surgical extirpation. The most serious clinical manifestation can be pulmonary embolism. The author presents four of his own observations with localization on the external jugular vein, the v. cephalica antebrachii, the anterior tibial vein and v. dorsalis digiti manus. 相似文献
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Cerebral aneurysms can present in a variety of special circumstances. Aneurysmal subarachnoid hemorrhage (SAH) can complicate systemic or neoplastic disease, head injuries, arterial dissection, and other cerebrovascular conditions. Aneurysms associated with non-saccular configuration or giant size can make surgical or endovascular intervention difficult if not impossible. This article will review these uncommon aneurysms and their management. 相似文献
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Extradural aneurysms have distinct characteristics from their intradural counterparts. Most extradural aneurysms cannot be treated by direct surgical exposure and clip ligation or by direct endovascular means without parent vessel sacrifice. Arterial occlusion with or without bypass grafting remains the traditional treatment. Controversy about the "best" or "proper" technique of arterial balloon test occlusion is rivaled only by that of the necessity for bypass grafting when apparent tolerance for arterial occlusion has been demonstrated. 相似文献
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Immunity to the intracellular protozoan, Toxoplasma gondii, in mice is of the premunition type. Chemoprophylaxis with sulfadiazine normally permits mice to develop immunity to virulent organisms. However, nude (nu/nu) mice, which lack the thymus, failed to develop immunity to toxoplasma during 3 weeks of drug therapy while their hirsute littermates developed immunity during this period. When nude mice were injected intraperitoneally with thymus cells from hirsute littermates, they became able to develop immunity to toxoplasma during drug prophylaxis. The injection of bone marrow cells or high-titered specific antibody did not prolong survival after sulfadiazine was discontinued. Therefore, it appears that immunity to toxoplasma in mice is dependent upon active cellular immunity while the role of antibody is uncertain. 相似文献
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Ultrastructural and cytochemical studies on the remodelling of the rat tracheal cartilage have been carried out. The thickness of the tracheal cartilage was constant, during the observation periods (1 to 54 days after birth). The external perichondrium of the tracheal cartilage consisted of active fibroblasts and intercellular fibrils. The inner part of this perichondrium was a chondrogenic layer, where appositional growth was taking place. On the other hand, the internal perichondrium contained fibroblast-like cells, which were nearly twice as large as the external perichondrial fibroblasts in size and were arranged in three or four layers. The cells had well developed organella and large vacuoles which contained numerous fragments of fibrils and/or glycosaminoglycan. Many cytoplasmic processes protruded to the cartilage matrix, where the intercellular fibrils were particularly irregular in arrangement. Some vacuoles included collagen fibrils. Based on an intense acid phosphatase activity in these vacuoles and other findings, the fibrils were thought to be phagocytosed collagen of the cartilage matrix. An extensive alkaline phosphatase activity was demonstrated on the plasma membrane of fibroblasts and chondroblasts in the external perichondrium. The present investigation revealed distinct functional difference between the external and internal perichondrium of the tracheal cartilage. It is resorbed at the internal perichondrium, while it appositionally grows at the external perichondrium. The fibroblast-like cells of the internal perichondrium play an essential role in resorption of the matrix in cartilage remodelling. 相似文献
18.
W Hepp 《Canadian Metallurgical Quarterly》1996,121(12):1058-1062
Extracranial carotid artery aneurysms occur very seldom. Here will be reported on 15 aneurysms (11 arteriosclerotic, 3 false and 1 dissecting aneurysm). Therapy of choice during the second half of this period was aneurysm exstirpation and PTFE interposition, twice with reinsertion of the external carotid artery. No patient died perioperatively, one permanent and one transient ischemic neurologic deficit occurred. Three lesions of the cranial nerves recovered completely. As to avoid cerebral embolisation each extracranial carotid artery aneurysm should be operated on if possible. This can be managed with tolerable risk and represents an effective embolic prophylaxis. 相似文献
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LB Davidovic SI Lotina DM Kostic IS Cinara SD Cvetkovic DM Markovic BR Vojnovic 《Canadian Metallurgical Quarterly》1998,22(8):812-817
Altogether 59 patients with 76 popliteal artery aneurysms were treated during the last 36 years. There were 50 (85%) male and 9 (15%) female patients with an average age of 61 years. Nineteen (32%) patients had bilateral aneurysms. The clinical manifestations of the aneurysms included ruptures 4 (5.3%); deep venous thrombosis 4 (5.3%); sciatic nerve compression 1 (1.3%); leg ischemia 52 (68.4%), and asymptomatic pulsatile masses 15 (19.7%). Seventy (92%) aneurysms were atherosclerotic, one (1.3%) mycotic, and four (5.3%) traumatic; one (1.3%) developed owing to fibromuscular displasia. Seven (9.2%) small, asymptomatic aneurysms were not operated on. Reconstructive procedures end-to-end anastomosis, graft interposition, bypass) after aneurysmal resection or exclusion using a medial or posterior approach were done in 59 cases. An autologous saphenous vein graft was used in 49 cases, polytetrafluoroethylene (PTFE) in 5, and heterograft in 2 cases. The in-hospital mortality rate was 2.9%, the early patency rate 93.3%, and limb salvage 95%. The long-term patency rate after a mean follow-up of 4 years was 78% and long-term limb salvage 89%. The total limb salvage was 73%, and the total amputation rate was 27%. The dangerous complications associated with popliteal artery aneurysms and the good results after elective procedures suggest that operative treatment is appropriate. 相似文献
20.
Cardiac chamber enlargement and hypertrophy are normal physiologic responses to repetitive endurance exercise activity in human beings and domestic dogs. Whether similar changes occur in wild animals as a consequence of increased activity is unknown. We found that free-ranging gray wolves (Canis lupus, n = 11), the archetypical endurance athlete, have electrocardiographic evidence of cardiac chamber enlargement and hypertrophy relative to sedentary captive gray wolves (n = 20), as demonstrated by significant increases in QRS duration, QT interval, and QT interval corrected for heart rate, a tendency towards increased Q, R, and S wave voltages in all leads, and a significant decrease in heart rate. We conclude that exercise activity level and therefore lifestyle affects physiologic variables in wild animals. An immediate consequence of this finding is that physiologic measurements obtained from a captive wild-animal population with reduced exercise activity level may not accurately reflect the normal physiologic state for free-ranging members of the same species. 相似文献