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991.
JF McDermott PE Tanguay SC Scheiber D Juul JH Shore GJ Tucker L McCurdy LC Terr 《Canadian Metallurgical Quarterly》1993,150(7):1077-1080
OBJECTIVE: The aim of this study was to examine the reliability (examination stability) of the American Board of Psychiatry and Neurology (ABPN) Part II (oral) examination in psychiatry. METHOD: The authors analyzed the consistency (agreement between grades given by two independent examiners) for a 1-year examination cycle using a weighted kappa statistic and compared different parts of the examination (live patient and videotape), different examination sites, different days, and different times of the day. RESULTS: There was no significant difference in agreement between examiners by different parts of the examination, examination site, day of the week, or time of day. CONCLUSIONS: The stability of the Part II ABPN examination in psychiatry is not influenced significantly by the format or site of administration. Candidate performance is the predominant factor in the determination of passing or failing grades. 相似文献
992.
Y Yang SE Raper JA Cohn JF Engelhardt JM Wilson 《Canadian Metallurgical Quarterly》1993,90(10):4601-4605
Cystic fibrosis (CF) is an inherited disease of epithelial cell ion transport that is associated with pathology in multiple organ systems, including lung, pancreas, and liver. As treatment of the pulmonary manifestations of CF has improved, management of CF liver disease has become increasingly important in adult patients. This report describes an approach for treating CF liver disease by somatic gene transfer. In situ hybridization and immunocytochemistry analysis of rat liver sections indicated that the endogenous CFTR (cystic fibrosis transmembrane conductance regulator) gene is primarily expressed in the intrahepatic biliary epithelial cells. To specifically target recombinant genes to the biliary epithelium in vivo, recombinant adenoviruses expressing lacZ or human CFTR were infused retrograde into the biliary tract through the common bile duct. Conditions were established for achieving recombinant gene expression in virtually all cells of the intrahepatic bile ducts in vivo. Expression persisted in the smaller bile ducts for the duration of the experiment, which was 21 days. These studies suggest that it may be feasible to prevent CF liver disease by genetically reconstituting CFTR expression in the biliary tract, using an approach that is clinically feasible. 相似文献
993.
994.
Y Assouline C Liguory O Ink J Fritsch AD Choury JF Lefebvre G Pelletier C Buffet JP Etienne 《Canadian Metallurgical Quarterly》1993,17(4):251-258
Between January 1989 and June 1990, endoscopic sphincterotomy was performed in 308 consecutive patients with common bile duct stones (mean age: 74 years). Complete clearance of common bile duct was achieved at the first attempt in 65% of cases. This rate was significantly related to the size and the number of biliary stones. The success rate reached 97 percent after repeated endoscopic sessions (127 patients), mechanical lithotripsy (20 patients), extracorporeal or intracorporeal lithotripsy (18 and 11 patients, respectively). During the month following the endoscopic sphincterotomy, 39 patients (13%) developed one or more complications and 11 patients (3.7%) died. The complication rate was related to the time elapsed between biliary opacification and endoscopic sphincterotomy (P = 0.04) and between endoscopic sphincterotomy and total common bile duct clearance (P = 0.0007). No patient younger than 75 years died, but death occurred in 4.5% of the patients older than 75 years. Thirty patients (10%) developed endoscopic sphincterotomy-related complications. Cholangitis and bleeding were the most frequent complications (4 and 2%, respectively). Cholangitis occurred more frequently among the patients older than 75 (P < 0.05) or when transhepatic guided endoscopic sphincterotomy or intracorporeal lithotripsy was used (P < 0.005). Cholangitis led to death in 2 patients, 86 and 87 years old (0.7%). Endoscopic sphincterotomy related complications developed within 48 hours in all but 4 patients (2 patients with pancreatitis and 2 patients with cholecystitis). 相似文献
995.
Salt wastage, plasma volume contraction and hypokalemic paralysis in self-induced water intoxication
RS Tanneau YL Pennec JF Morin JP Codet B Bourbigot M Garre G Le Menn 《Canadian Metallurgical Quarterly》1993,64(4):570-575
Eleven episodes of severe hyponatremia secondary to hiccup-induced potomania were recorded in 3 years in a man who had essential hypertension, a low protein intake and a normal diluting ability. Paradoxical increase in hematocrit and plasma protein with acute extensive natriuresis was associated as well as urine potassium loss and hypokalemia producing paralysis in 1 episode. During a chronic water loading test, the defect in water excretion was related to a low urine solute delivery which was partially reverted by the natriuretic response to plasma volume expansion, promoting water diuresis. In acute water intoxication, this natriuretic response was exaggerated, producing a brisk water diuresis. Plasma volume was rapidly normalized but without any improvement in plasma sodium due to the concomitant negative sodium balance. Thus, water diuresis persisted until plasma volume was significantly contracted. Potassium loss appeared to be related to sodium excretion. Metabolic disturbances have not reoccurred despite persistent hiccup and potomania during 2 years of urea therapy. 相似文献
996.
Luminol chemiluminescence in rat macrophages and granulocytes: the role of NO, O2-/H2O2, and HOCl 总被引:1,自引:0,他引:1
Luminol chemiluminescence was increased up to five-fold by L-arginine and markedly inhibited by NG-nitro-L-arginine (L-NNA) in phorbol ester (PMA) or opsonized zymosan-activated rat Kupffer cells, and in PMA-activated rat peritoneal and alveolar macrophages. While in Kupffer cells these effects did occur without pretreatment with lipopolysaccharides (LPS), LPS pretreatment was a requirement in peritoneal and alveolar macrophages. Azide (0.05 mM) had no effect on luminol chemiluminescence in the macrophages. The changes in luminol chemiluminescence were accompanied by parallel changes in nitric oxide (NO) formation. Macrophage superoxide anion radical (O2-) production was not significantly changed by addition of L-arginine and L-NNA nor by pretreatment with LPS. No hypochlorous acid (HOCl) formation was detectable in the macrophages. In contrast, in rat granulocytes activated by a variety of stimuli including PMA, zymosan, the chemotactic peptide formyl-methionyl-leucyl-phenylalanine and the calcium ionophore A23187 with or without pretreatment with LPS, L-arginine and L-NNA had no effect on luminol chemiluminescence. Luminol chemiluminescence, however, was largely inhibited by 0.05 mM azide. The activated granulocytes released significant amounts of HOCl but did not generate NO. These results demonstrate that NO may largely contribute to luminol chemiluminescence in rat macrophages, in which HOCl formation does not occur. On the other hand, HOCl is the reactive oxygen species responsible for luminol chemiluminescence in rat granulocytes, where NO is formed only in minor quantities, if at all. 相似文献
997.
PI Lobo C Spencer MT Douglas WC Stevenson TL Pruett 《Canadian Metallurgical Quarterly》1993,55(5):1063-1066
Recent reports indicate a higher incidence of both acute and chronic liver allograft rejection when, at the time of transplantation, the recipients serum contains donor-specific anti-HLA antibodies. From 9/89 to 5/91, 133 liver allografts were performed at our institution. Thirteen liver recipients had donor-specific IgG anti-HLA antibodies (complement-fixing) at the time of transplantation. In eleven patients, antibodies reacted to donor class I antigens while in 1 patient the donor-specific antibody had class II reactivity. Twelve patients have been followed for a minimum of 12 months (median 18 months, range 28-12 months). No hyperacute rejection was seen in any of the cases and four patients had acute rejections. Thus far only one of the twelve patients has biopsy evidence suggestive of chronic liver injury. The remaining have normal liver enzymes and bilirubin. Three of these twelve patients died (one from a myocardial infarction and the others from sepsis) accounting for a one-year graft survival of 75%. There was no significant statistical difference in the one-year graft survival in those recipients without donor-specific antibodies (i.e., 80.5%). In eight of the twelve patients, pretransplant preformed antibody level (PRA) was > 50%. In six of the thirteen patients donor-specific antibody was present at dilutions greater than 1:64. As previously reported, the donor-specific antibody disappeared from the serum posttransplant within hours and did not reappear. In vitro studies demonstrated no factor in portal or hepatic artery blood that could inhibit rabbit complement mediated lysis of anti-HLA antibodies. We conclude that it is not a contraindication to do liver transplants in the presence of donor-specific anti-HLA antibodies. 相似文献
998.
1. Microelectrode recording techniques were used to study the effects of several potassium channel blockers which are considered to be Class III antiarrhythmic compounds. The effects of (+)-sotalol, UK-66,914, UK-68,798 and E-4031 on action potential duration (APD) were determined in guinea-pig isolated papillary muscles. The compounds were evaluated under normoxic or hypoxic/ischaemic conditions at 36.5 degrees C and compared to glibenclamide, which is considered to be a blocker of ATP-dependent potassium channels. Prolongation of action potential duration at 90% repolarization (APD90) was taken as an indirect measure of potassium channel blockade. 2. Under normoxic conditions, the Class III compounds prolonged APD in a concentration-dependent manner. According to EC15 values, the order of potency of the Class III compounds was found to be UK-68,798 > E-4031 > UK-66,914 > (+)-sotalol. Glibenclamide did not significantly prolong APD90 under normoxic conditions. 3. Perfusion with an experimental hypoxic or ischaemic bathing solution produced qualitatively similar effects on action potentials. Over a period of 20-25 min in either of the experimental solutions, there was a small decrease in action potential amplitude (APA) and a prominent shortening of APD. The ischaemic solution also depolarized the resting membrane potential by about 15 mV. 4. (+)-Sotalol and UK-66,914 did not reverse the shortening of APD induced by perfusion with hypoxic Krebs solution. High concentrations of glibenclamide (10 microM) and UK-68,798 (30 and 60 microM) partially reversed the hypoxia-shortened APD. Glibenclamide was more potent and exhibited a greater time-dependent action than UK-68,798. 5. During experimental ischaemia, the Class III compound E-4031 (10 microM, n = 7) produced small, but significant, increases in the APD90 (11 +/-3 ms after 20 min) which were not clearly time-dependent(14 +/- 4 ms after 30 min). UK-68,798 (10 microM) also produced a small, but insignificant, increase in APD90(12 =/-6 ms at 20 min, n = 4). Higher concentrations of UK-68,798 (30 and 60 microM, n = 4) did not produce a consistently significant increase in APD90 during ischaemia: significance was only attained after 20 min in the presence of 60 microM UK-68,798 (24 +/- 12 ms). However, in marked contrast to the effects of the Class III compounds, glibenclamide (10 microM) produced large time-dependent increases in ischaemic APD90 (34 +/- 11 ms at 7 min, n = 9) which were significant 15 min or more after drug addition(52 +/- 12 ms at 20 min, n = 7; 74 +/- 5 ms at 30 min, n = 6).6. The present microelectrode data suggest that blockers of ATP-dependent potassium channels, such as glibenclamide, might prove to be more effective than Class III compounds against ischaemia-induced shortening of cardiac action potentials. 相似文献
999.
RV Cellona GP Walsh TT Fajardo RM Abalos EC dela Cruz L Guido-Villahermosa MV Felicio-Balagon GJ Steenbergen JT Douglas 《Canadian Metallurgical Quarterly》1993,61(2):192-198
An indirect enzyme-linked immunosorbent assay (ELISA) using natural disaccharide octyl bovine serum albumin (ND-O-BSA) as antigen was used in testing leprosy patients, contacts and a normal population in Cebu, The Philippines, from 1985 to 1989. A total of 1413 persons were studied. The results suggested that ELISA reactivity and the bacterial index (BI) correlate in a general way. In multibacillary (MB) leprosy, positivity ranges from 54.2% to 92.3% among patients with a BI of < 2+ to > 4+ on the Ridley scale, with an overall average of 84.5%. Paucibacillary (PB) leprosy patients have a low degree of reactivity, with only 15.0% ELISA positive. The test is more efficient in detecting MB than PB leprosy. The contacts of MB leprosy showed 6.5% positivity; contacts of PB leprosy, 7.0% positivity. The normal population showed 1.7% positive ELISA or 17 per thousand population, which is very much less than that of the household contacts. However, because the normal population is a much larger population than the household contact population in a community, more new leprosy cases would emanate from it. Leprosy workers are concerned about the transmission of the disease to household contacts. However, for the reason stated above, we should be more concerned with the silent spread of the disease to the normal population in the community.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
1000.
DB Fram TA Aretz JF Mikan A Raisner JF Mitchel LD Gillam DD Waters RG McKay 《Canadian Metallurgical Quarterly》1993,126(4):969-978
The purpose of this study was to assess the safety and histologic effects of radiofrequency thermal balloon angioplasty in the coronary vasculature of normal pigs. Radiofrequency thermal balloon angioplasty was performed in 30 coronary arteries of 16 nonatherosclerotic pigs. Heated inflations were performed at either 50 degrees, 60 degrees, or 70 degrees C for 30 or 60 seconds, and were compared with five nonheated inflations in five additional arteries. All balloon inflations were performed at 2 atm pressure with a balloon/vessel diameter ratio of 1.2 to 1. Heart rate, arterial pressure, and left ventricular pressure were monitored continuously for each animal. A 12-lead ECG, coronary angiography, and two-dimensional transthoracic echocardiography were performed before and 1 hour after each balloon inflation. Each animal was subsequently put to death for postmortem cardiac examination. Heated inflations were well tolerated in 28 of the 30 arteries without significant adverse effects. During one inflation, ventricular fibrillation occurred because of prolonged ischemia from an occlusive guiding catheter. In another artery, a heated inflation resulted in a dissection with a transient decrease in distal coronary flow. Histologic examination revealed a significant increase in wall thinning and elastic fiber straightening with heating at 70 degrees C for both 30 and 60 seconds, and a significant increase in intracoronary thrombus with heating at 70 degrees C for 60 seconds. Depth of periarterial myocardial heat necrosis paralleled the increase in temperature, with an average depth of 166 microns at 50 degrees C, 312 microns at 60 degrees C, and 1031 microns at 70 degrees C. In vivo, radiofrequency coronary angioplasty can be performed relatively safely without significant electrical, hemodynamic, or ischemic changes beyond those seen with conventional nonthermal angioplasty. The extent of heat-induced vessel wall thinning, elastic tissue straightening, intracoronary thrombus formation, and periarterial myocardial necrosis are all related to balloon temperature or duration of heating. 相似文献