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931.
OBJECTIVE: Our goal was to evaluate the clinical reliability of a new software system employing 3-dimensional (3D) virtual anatomic reconstruction and intraluminal virtual exploration for detection of choledocholithiasis and preoperative visualization of the biliary anatomy. SUMMARY BACKGROUND DATA: Virtual reality systems have been proposed for gastroscopy, bronchoscopy, and colonoscopy, as well as for the 3D reconstruction of liver anatomy and hepatic lesions. The impact of these systems in preoperative diagnostics has not been established due to the lack of large clinical series evaluating their reliability. METHODS: From November 2000 to July 2002, all patients presenting to our Institute with suspected choledocholithiasis were prospectively included in the study. All patients underwent conventional magnetic resonance cholangiopancreatography (MRCP) and either intraoperative cholangiogram (IOC) or endoscopic retrograde cholangiopancreatography (ERCP). The digital data from MRCP were incorporated into an original virtual reality software system to generate a 3D reconstruction. All 3D reconstructions were evaluated by a surgeon and a computer software engineer who were blind to the results of the IOC or ERCP. Sensitivity and specificity were then calculated based on the results of either the IOC or ERCP. RESULTS: Sixty-five patients were enrolled in the study. The average time required to reconstruct the images into navigable virtual reality was 7.5 minutes (range, 4-13.5). The 3D virtual cholangioscopy had sensitivity and specificity rates of 71% and 91%, respectively, compared with 61% and 86% of the standard MRCP. CONCLUSION:: The 3D virtual cholangioscopy provides detailed preoperative reconstruction of biliary anatomy and reliable identification of choledocholithiasis with acceptable sensitivity and specificity in a clinical setting. Newer software developments may further enhance its accuracy, so that virtual cholangioscopy might challenge or replace more invasive diagnostic measures in the near future.  相似文献   
932.
OBJECTIVE: To investigate the efficiency of endovascular smooth muscle cell (VSMC) seeding in promoting healing and stability in already-developed aneurysms obtained by matrix metalloproteases (MMPs)-driven injury. SUMMARY BACKGROUND DATA: VSMCs are instrumental in arterial healing after injury and are in decreased number in arterial aneurysms. This cellular deficiency may account for poor healing capabilities and ongoing expansion of aneurysms. METHODS: Aneurysmal aortic xenografts in rats displaying extracellular matrix injury by inflammation and proteolysis were seeded endoluminally with syngeneic VSMCs, with controls receiving culture medium only. Diameter, structure, and the destruction/reconstruction balance were assessed. RESULTS: Eight weeks after endovascular infusion, aneurysmal diameter had increased further, from 3.0 +/- 0.3 mm to 10.9 +/- 6.5 mm (P = 0.009), and medial elastin content had decreased from 36.5 +/- 8.5 to 5.2 +/- 5.5 surface-percent (S%; P = 0.009) in controls, whereas these parameters remained stable in the seeded group (3.0 +/- 0.3 to 2.7 +/- 0.2 mm, P = 0.08; 36.5 +/- 8.4 to 31.6 +/- 9.7 S%, P = 0.22). VSMC seeding was followed by a decrease in mononuclear infiltration. MMP-1, -3, -7, -9, and -12 mRNA contents were sharply decreased in the diseased wall in response to seeding. Tissue inhibitor of metalloproteinase-1, -2, and -3 mRNAs in the intima were increased in a 2 to 10 magnitude in comparison with controls. Gelatin zymography showed the disappearance of MMP-9 activity and reverse zymography a strong increase in tissue inhibitor of metalloproteinase-3 activity in the seeded group. VSMC-seeded aneurysms were rich in collagen and lined with an endothelium instead of a thrombus in controls. CONCLUSIONS: VSMCs endovascular seeding restores the healing capabilities of proteolytically injured extracellular matrix in aneurysmal aortas, and stops expansion.  相似文献   
933.
Dhonneur G  Combes X  Chassard D  Merle JC 《Anesthesia and analgesia》2004,98(4):986-9, table of contents
Prick tests are frequently used for the authentication of neuromuscular blocking drugs (NMBDs) as causative drugs for anaphylactic reactions during anesthesia. Unfortunately, the actual threshold concentration for skin testing remains debatable for most NMBDs. We studied the flare and wheal responses to prick tests with rocuronium and vecuronium. Thirty healthy, nonatopic, anesthesia-naive male and female volunteers (14 men and 16 women) from 18 to 40 yr of age were assigned randomly to receive a total of 10 prick tests-4 ascending dilutions (1:1000, 1:100, 1:10, and 1) of rocuronium and vecuronium and 2 controls-on both forearms. An assessor blinded to the assignment monitored systemic and skin responses to NMBDs and measured wheal and flare surfaces immediately after and 15 min after prick tests. None of the volunteers experienced any immediate systemic or cutaneous responses to rocuronium or vecuronium. Although a dilution of 1:1000 of both NMBDs failed to promote any skin response at 15 min, 50% and 40% of the subjects had a positive skin reaction to undiluted rocuronium and vecuronium, respectively. We demonstrated a sex effect related to smaller threshold concentration-induced cutaneous reactions in female volunteers to both muscle relaxants. Our observation questions the reliability of prick testing with undiluted solutions of rocuronium and vecuronium for the diagnosis of allergy. IMPLICATIONS: Building concentration-skin response curves to prick tests with rocuronium and vecuronium in healthy, nonatopic, anesthesia-naive male and female volunteers demonstrated that the nonreactive concentration for both muscle relaxants is the 1:1000 dilution of the stock solutions. Our observation calls into question the past practice of prick-testing skin for sensitivity to neuromuscular blocking drugs by using undiluted solutions.  相似文献   
934.
The pulmonary veins have been demonstrated to play an important role in generating atrial fibrillation. We report the first successful endoscopic epicardial isolation of the pulmonary veins in a patient with permanent atrial fibrillation, along with a 1-year follow-up. The procedure consisted of making a conduction block around the pulmonary veins with a flexible microwave energy delivery probe. The probe was placed endoscopically on the left atrial epicardium with the aid of robotic instruments.  相似文献   
935.
Autopsies of exhumed cadavers can reveal important evidence for clarification of medical insurance and social issues. This study concerns insects sampled on 22 exhumed cadavers in the Lille area. For each corpse, the species and the stages of development were noted, as well as the time elapsed after burial, the location of the cemetery, the stage of decay and possible preservation treatment. A total of eight Diptera and two Coleoptera species were sampled on the corpses. The relationships between entomofauna and conditions of burial are discussed. Three species were regularly found because of their preference for underground environments or closed environments: Conicera tibialis, typically associated with buried bodies, Leptocera caenosa which is known to be associated with human faeces, water closets, caves and cracked soil pipes, and Ophyra capensis, sometimes found on human bodies kept indoors for several months, where blowflies have not had access. Triphleba hyalinata, which is associated with human bodies in wooden coffins, was found only twice.  相似文献   
936.
This is the first multicenter, randomized, open-label study to compare the efficacy and safety of cyclosporine A microemulsion (CsA-ME) (Neoral, Novartis, Basel, Switzerland ) with C2 monitoring versus tacrolimus in de novo liver transplant recipients. Patients were stratified according to hepatitis C virus status and randomized to receive CsA-ME (n= 250) or tacrolimus (n= 245) with steroids, with or without azathioprine. The primary endpoint was the incidence of biopsy-proven acute rejection (BPAR) at 3 months. Secondary endpoints included death or graft loss and safety evaluations at 6 months. The incidence of BPAR at 3 months was 26% in the CsA-ME group and 24% in the tacrolimus group (not significant). At 6 months, 89% of patients receiving CsA-ME and 88% of patients receiving tacrolimus were alive with a functioning graft. Among the hepatitis C virus-positive patients, there was no difference in BPAR, but death or graft loss was more frequent in those receiving tacrolimus (15% vs. 6%, P <0.05). Diabetes mellitus (14% vs. 7%, P <0.02) and diarrhea (29% vs. 14%, P <0.001) were significantly more often reported in patients receiving tacrolimus. The incidence of hypertension was similar in both groups. At 6 months, the median total cholesterol was 4.7 mmol/L (2.9-7.4 mmol/L) in the CsA-ME arm versus 4.3 mmol/L (2.5-6.4 mmol/L) in the tacrolimus arm; the median serum creatinine was 106 micromol/L (52-238 micromol/L) in the CsA-ME arm versus 103 micromol/L (44-477 micromol/L) in the tacrolimus arm. Efficacy is equivalent with CsA-ME using C2 monitoring or tacrolimus in liver transplant recipients. The incidence of adverse events is comparable except for a significantly higher incidence of diabetes mellitus and diarrhea in the tacrolimus group. Both agents are effective primary immunosuppressants in liver transplant recipients.  相似文献   
937.
938.
TO PREVENT ISCHEMIC STROKE: Three types of measures should be taken: correction of the vascular risk factors, administration of antithrombotic agents and carotid revascularisation in patients selected on the basis of clinical and imaging criteria. CAROTID REVASCULARISATION MEASURES: The optimal indications are carotid surgery for severe symptomatic stenosis, while the benefits are marginal in severe asymptomatic stenosis and in moderate symptomatic stenosis. INDICATIONS FOR PERCUTANEOUS ANGIOPLASTY WITH PLACING OF AN ENDOPROSTHESIS: Angioplasty with endoprosthesis, a possible alternative to surgery, must be restricted to symptomatic stenosis either in randomised studies or in severe stenosis in patients in whom surgery is technically contraindicated.  相似文献   
939.
To analyze the current management recommendations among French-speaking physicians treating infants with antenatal renal pelvis dilatation, we surveyed 83 pediatric nephrologists and 68 pediatric urologists by questionnaire. A total of 45 (54%) pediatric nephrologists and 38 (56%) pediatric urologists responded. The threshold for the diagnosis of abnormal fetal renal pelvis dilatation was significantly higher among pediatric urologists than nephrologists. All responders perform renal ultrasound examinations after birth. Postnatal renal pelvis dilatation was considered abnormal if the anteroposterior diameter was 11±1.9 mm by the pediatric urologists and 9±2.9 mm by the pediatric nephrologists (P=0.003). Pediatric urologists were more likely than nephrologists to recommend routine voiding cystourethrography [41% versus 20% (P=0.04)]. Mercaptoacetyl-triglycine renography was the most routinely used tool to achieve functional evaluation during follow-up among the responders. Pediatric urologists were more likely to recommend surgical treatment in dilated kidneys with initial function <40%. In conclusion, pediatric urologists had significantly higher thresholds for the detection of prenatal and neonatal renal pelvis dilatation. They also more frequently recommended routine voiding cystourethrography and surgical therapy of dilated kidneys with low function than pediatric nephrologists. The variability in attitudes is most probably due to the absence of clear guidelines based on prospective and controlled trials.The following workers contributed to this study. For the French-speaking Society of Pediatric Nephrology (SNP): J. Al Hosri (Hôpital Nord, Amiens, France), J.L. André (Hôpital dEnfants, Nancy, France), A. Bensman (Hôpital Trousseau, Paris, France), E. Berard (LArchet II, Nice, France), J.P. Bertheleme (Centre Hélio Marin, Roscoff, France), F. Bouissou (Hôpital des Enfants, Toulouse, France), G. Bourdat-Michel (CHU, Grenoble, France), G. Champion (CHU, Angers, France), S. Cloarec (Hôpital Clocheville, Tours, France), L. Collard (Hôpital E. Herriot, Lyon, France), J.C. Davin (Emma Childrens Hospital, Amsterdam, Holland), L. de Parscau (Hôpital Augustin Morvan, Brest, France), S. Decramer (Hôpital des Enfants, Toulouse, France), V. Desvignes (CH, Clermont Ferrand, France), R. Donckerwolcke (AZ, Maastricht, Holland), J. Ehrich (MHH, Hannover, Germany), M. Fischbach (Hôpital de Hautepierre, Strasbourg, France), M. Foulard (Hôpital Jeanne de Flandre, Lille, France), M.S. Ghuysen (CHU Sart Tilman, Liège, Belgium), J.B. Gouyon (Hôpital dEnfants, Dijon, France), J.P. Guignard (CHUV, Lausanne, Switzerland), C. Guyot (CHU, Nantes, France), P. Hansen (Hôpital Tivoli, La Louvière, Belgium), J.P. Hehunstre (Hôpital Pellegrin, Bordeaux, France), F. Janssen (Hôpital Universitaire des Enfants, Brussels, Belgium), M.J. Krier (Hôpital dEnfants, Nancy, France), A. Lahoche-Manucci (Hôpital Jeanne de Flandre, Lille, France), H. La Selve (Centre Hélio Marin, Roscoff, France), M.P. Lavocat (Hôpital Nord, Saint Etienne, France), C. Loirat (Hôpital Robert Debré, Paris, France), J. Lombet (CHR La Citadelle, Liège, Belgium), A. May (CH Sud Francilien, Evry, France), D. Morin (Hôpital Arnaud de Villeneuve, Montpellier, France), J.B. Palcoux (Hôtel Dieu, Clermont Ferrand, France), S. Palomera (CTMR, Bordeaux, France), C. Pietrement (American Memorial Hospital, Reims, France), S. Ploos van Amstel (Emma Childrens Hospital, Amsterdam, Holland), W. Proesmans (UZ Gasthuisberg, Leuven, Belgium), N. Ranguelov (CHU, Charleroi, Belgium), B. Roussel (American Memorial Hospital, Reims, France), M.H. Said (Hôpital E. Herriot, Lyon, France), A. Taque (Hôpital de Pontchaillou, Rennes, France), M. Tsimaratos (Hôpital La Timone, Marseille, France). R. Van Damme-Lombaerts (UZ Gasthuisberg, Leuven, Belgium)For the French-speaking Pediatric Urology Study Group (GEUP): T. Aivazoglou (Aglaia Kyriakou Hospital, Athens, Greece), J.L. Alain (CHU Dupuytren, Limoges, France), P. Alessandrini (Hôpital Nord, Marseille, France), G. Audry (Hôpital Trousseau, Paris, France), M. Avérous (Hôpital Lapeyronie, Montpellier, France), R. Besson (Hôpital Jeanne de Flandre, Lille, France), J. Biserte (Hôpital Huriez, Lille, France), B. Boillot (CHU Albert Michallon, Grenoble, France), J.M. Bondonny (Hôpital des Enfants, Bordeaux, France), J.P. Bonnet (Hôpital Simone Veil, Montmorency, France), P. Bugmann (Hôpital des Enfants, Geneva, Switzerland), F. Collier (Hôpital Universitaire des Enfants, Brussels, Belgium), J.F. Colombani (CHU, Fort-de-France, France), H. Dodat (Hôpital E. Herriot, Lyon, France), B. Dore (CHU, Poitiers, France), A. El Ghoneimi (Hôpital R. Debré, Paris, France), C. Esposito (Universitary Hospital, Naples, Italy), B. Fremond (Clinique Chirurgicale infantile, Rennes, France), P. Frey (CHUV, Lausanne, Switzerland), S. Geiss (Centre de la Mère et lEnfant, Colmar, France), I. Germouty (CHU, Brest, France), Y. Heloury (CHU, Nantes, France), A. Lacombe (Hôpital Clocheville, Tours, France), S. Lortat-Jacob (Hôpital Necker-Enfants Malades, Paris, France), T. Merrot (Hôpital Nord, Marseille, France), R. Moog (Hôpital de Hautepierre, Strasbourg, France), G. Morisson-Lacombe (Hôpital Saint Joseph, Marseille, France), J. Moscovici (Hôpital des Enfants, Toulouse, France), P. Mouriquand (Hôpital Debrousse, Lyon, France), E. Sapin (CHU, Dijon, France), A. Savanelli (Universitary Hospital, Catanzaro, Italy), M. Schmitt (Hôpital dEnfants, Nancy, France), H. Steyaert (Fondation Lenval, Nice, France), C. Tölg (CHU, Fort-de-France, France), J.S. Valla (Fondation Lenval, Nice, France), F. Varlet (Hôpital Nord, Saint Etienne, France), P. Wallon (Centre de Chirurgie de lEnfant, Bordeaux, France), D. Weil (Centre Hospitalier, Le Mans, France)  相似文献   
940.
OBJECTIVE: To investigate the influence of a calibrated exercise on the progression of structural lesions in an experimental model of osteoarthritis (OA) in the rat, and to explore the effect of exercise on the level of chondrocyte caspase-dependent apoptosis and of Hsp70. METHODS: The OA model was induced by anterior cruciate ligament transection (ACLT). Rats were placed in 4 experimental groups: operated (ACLT) free moving rats, and 3 exercise groups (slight, moderate and intense) subjected to running training. Rats were killed 14 and 28 days after surgery. RESULTS: On D14 histological assessment demonstrated a beneficial influence of a slight and a moderate exercise vs control ACLT group. Hsp70 increased significantly in the moderate group vs controls. On D28, histological lesions strongly decreased in the slight and moderate exercise groups vs ACLT group, while an intense effort abolished this beneficial trend. Interestingly, the concomitant course of apoptotic events (caspase 3-positive cells) and the co-expression of Hsp70 in the various groups varied, when significant, in an inverse manner. In the intense group this overexpression was not noted, as a "burn out" appeared, thus leading to a loss of this protective effect. CONCLUSION: This study shows that a calibrated slight or moderate exercise exerts a beneficial influence on the severity of chondral lesions in ACLT rats. Conversely, a strong effort abolishes this chondroprotective effect. This effect could be related to a reduced level of chondrocyte apoptosis through anti-apoptotic capacities of stress-induced Hsp70 overexpression.  相似文献   
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