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101.
Gebhard S Coindre JM Michels JJ Terrier P Bertrand G Trassard M Taylor S Château MC Marquès B Picot V Guillou L 《The American journal of surgical pathology》2002,26(5):601-616
The clinicopathologic and immunohistochemical features of 63 pleomorphic liposarcomas are presented. There were 35 men and 28 women (median age 63 years; range 18-93 years). Tumor size ranged from 2 to 23 cm (median 10 cm). Tumor locations included lower extremity (36.5%), especially the thigh (28.5%), limb girdles (17.5%), upper extremity (16%), thoracoabdominal wall (9.5%), and internal trunk (20.5%). A total of 75% were deep seated and/or extracompartmental. Histologically, lesions show a varying combination of lipogenic and nonlipogenic areas characterized by malignant fibrous histiocytoma-like, round cell liposarcoma-like, and/or epithelioid/carcinoma-like features. A pericytic pattern was focally present in 15 (24%) tumors. Eighteen (29%) lesions were grade 2, and 45 (71%) were grade 3 sarcomas. Tumor necrosis was observed in 51 (81%) cases, vascular invasion in three, and mitotic counts ranged from 3 to 124 per 10 high power fields (median 25). Lipogenic areas were S-100 protein immunoreactive, at least focally, in 20 of 42 (48%) cases. Nonlipogenic areas showed focal reactivity for smooth muscle actin (24 of 49; 49%), desmin (9 of 48; 19%), CD34 (18 of 45; 40%), S-100 protein (5 of 49, 10%), CD68 (6 of 46, 13%), and epithelial membrane antigen (13 of 49, 26.5%). Epithelioid areas showed epithelial membrane antigen (4 of 11; 36%) but not cytokeratin (0 of 11) reactivity. Treatment procedures in 51 patients consisted of simple tumorectomy (16) and wide excision (33). Five and 31 patients received neoadjuvant and adjuvant chemotherapy and/or radiation therapy, respectively. Follow-up (48 patients, range 7-276 months; median 38 months) showed a 45% local recurrence rate and a 42.5% metastasis rate, metastases occurring mostly in lungs and pleura. Seventeen patients (35%) died of disease, of whom none was metastatic at diagnosis. Five-year overall, metastasis-free, and local recurrence-free survivals were 57%, 50%, and 48%, respectively. Patient age > or =60 years, truncal tumor location, deep situation, tumor size >5 cm, vascular invasion, and incomplete tumor excision were significant adverse prognostic factors. Tumor grade and histology did not affect patient outcome. In conclusion, pleomorphic liposarcoma is a rare, often deep-seated and limb-based aggressive and metastasizing neoplasm of late adulthood. It shows a wide range of morphologic appearances, but tumor grade and histology have no effect on patient outcome. 相似文献
102.
BACKGROUND: The purpose of this study was to report results, effectiveness and safety of implanting a negative collagen/HEMA copolymer posterior chamber phakic intraocular lens in moderate to highly myopic eyes. MATERIAL AND METHODS: 23 eyes from 12 patients with a mean preoperative spherical equivalent refraction of - 10.94 +/- 5.97 D underwent a refractive procedure with the Staar ICL trade mark posterior chamber phakic intraocular lens. The average follow-up was 12.9 +/- 7.4 months (range 4 - 24 months). Preoperative and postoperative uncorrected and best corrected visual acuity, subjective refraction, intraocular pressure, keratometry, ICL trade mark centration and anterior subcapsular opacities were evaluated. RESULTS: Postoperative uncorrected visual acuity improved in all eyes. The best corrected visual acuity increased from 0.82 +/- 0.39 preoperatively to 1.05 +/- 0.24 postoperatively. The gain in visual acuity was statistically significant (Student t-test, p = 0.0097). The mean postoperative spherical equivalent refraction was - 0.82 +/- 1.42 D (p < 0,0001). The mean postoperative intraocular pressure was 15.65 +/- 2.72 mm Hg. The intraocular contact lens remained well centred in all eyes and no anterior subcapsular opacities were observed. Three patients underwent transcient complication without affecting the visual outcome. CONCLUSION: The use of a posterior chamber phakic intraocular lens in myopic eyes is a safe procedure to correct moderate to high myopia. Long-term results are still unknown. 相似文献
103.
Loichot C Grima M De Jong W Helwig JJ Imbs JL Barthelmebs M 《European journal of pharmacology》2002,454(2-3):241-247
The effects of oxytocin on renin secretion by denervated kidney were investigated in vivo, by infusing the peptide directly into the renal artery of anaesthetized rats. Renin secretion was calculated by the renal veno-arterial difference in plasma renin activity multiplied by renal plasma flow. The intra-renal arterial (i.r.a.) infusion of oxytocin (1.5 or 15 ng/kg/min, 10 min) induced a sixfold increase in renin secretion as compared to vehicle-treated controls, without effects on renal blood flow, mean arterial blood pressure, glomerular filtration rate or natriuresis. The effect of oxytocin (1.5 ng/kg/min) was prevented by pretreatment with an oxytocin receptor antagonist, desGly-NH(2),d(CH(2))(5)[D-Tyr(2),Thr(4),Orn(8)]vasotocin] (5.6 microg/kg bolus i.v. 20 min before oxytocin infusion, followed by 2.8 microg/kg/min i.r.a.). Nadolol (2.5 mg/kg i.v.), a beta-adrenoceptor antagonist, also blocked the oxytocin-induced increase in renin secretion. These results show that oxytocin is able to stimulate renin release by activating oxytocin receptors but that beta-adrenoceptors also seem to be involved. 相似文献
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Berr C Helbecque N Sazdovitch V Mohr M Amant C Amouyel P Alpérovitch A Hauw JJ 《Acta neuropathologica》2003,106(1):71-74
We studied whether codon 129 polymorphism of the PrP gene modulates the presence of tau- and Abeta-associated lesions among 188 patients over 70 years of age without evidence of dementia. Val allele carriers, either heterozygotes or homozygotes, were more frequently affected by Abeta-associated lesions than non Val allele carriers, whereas there were no differences for tau-positive neurones. Val allele carriers also had more focal and diffuse Abeta deposits. This association was most significant in the highest Braak's stages for neurofibrillary tangles (>/=III). In this group, cases with at least one Val allele had nearly twice as many Abeta-associated lesions. The most affected areas were the entorhinal cortex, TF-TH and the superior temporal cortex, where odds ratios for focal Abeta deposits ranged from 3.5 to 4.6. 相似文献
106.
Medial pancreatectomy: a multi-institutional retrospective study of 53 patients by the French Pancreas Club 总被引:19,自引:0,他引:19
Sauvanet A Partensky C Sastre B Gigot JF Fagniez PL Tuech JJ Millat B Berdah S Dousset B Jaeck D Le Treut YP Letoublon C 《Surgery》2002,132(5):836-843
BACKGROUND: The results of medial pancreatectomy have been previously reported anecdotally. The purpose of the study was to provide short- and long-term results of MP in a large multicenter collective series. METHODS: From 1990 to 1998, 53 patients (mean age +/- SD = 49 +/- 15 years) underwent medial pancreatectomy for primary cystic neoplasms of pancreas (n = 19), endocrine neoplasms (n = 17), intraductal papillary mucinous neoplasms (IPMN) (n = 6), fibrotic stenosis of the Wirsung's duct (n = 4), or other benign (n = 4) or malignant (n = 3) diseases. The proximal (right) pancreatic remnant was sutured (n = 53), and the distal (left) remnant was either anastomosed to a jejunal loop (n = 26), to the stomach (n = 25), or oversewn (n = 2). Medial pancreatectomy was indicated in 3 patients (6%) because of failed enucleation, in 3 (6%) to prevent worsening of preexisting diabetes, or to prevent de novo diabetes in a patient with chronic pancreatitis, and deliberately in the 47 others. RESULTS: The length of the resected pancreas was 5.0+/- 2.2 cm (range, 2-15). One patient (2%) died from a pancreatic fistula and portal thrombosis. Three patients were reoperated on because of complications related to the left pancreas, which was partially or totally resected. Pancreatic fistula developed in 16 patients (30%). Mean delay for the return of oral feeding was related to the presence of a pancreatic fistula. At follow-up (median = 26 months, range, 12-131), 1 pancreatic recurrence and 1 de novo diabetes occurred in patients without IPMN. In patients with IPMN, the rates of pancreatic recurrence and diabetes were 40% (2/5), respectively. CONCLUSIONS: Medial pancreatectomy effectively preserves long-term endocrine function and is associated with a low risk of local recurrence, except in patients with IPMN. However, there is a high risk (30%) of PF after medial pancreatectomy. 相似文献
107.
Aya AG de la Coussaye JE Robert E Ripart J Cuvillon P Mazoit JX Jeannes P Fabbro-Péray P Eledjam JJ 《Anesthesiology》2002,96(3):641-650
BACKGROUND: The study was designed to compare the effects of equimolar concentrations of racemic bupivacaine, levobupivacaine, and ropivacaine on ventricular conduction, anisotropy, duration and homogeneity of refractoriness, and wavelengths, and to provide a potency ratio for effects on conduction velocity. METHODS: Isolated frozen rabbit hearts (which leave a thin layer of surviving epicardial muscle) were treated with 0.1, 1, and 10 mum racemic bupivacaine, levobupivacaine, or ropivacaine. Left ventricular longitudinal and transverse conduction velocities, anisotropic ratio, minimum pacing cycle length, use dependency, duration and dispersion of ventricular effective refractory period, and wavelengths were studied. A high-resolution mapping system was used for data acquisition. In addition to two-way analysis of variance for repeated measures, data for conduction velocities were fitted simultaneously using a nonlinear mixed-effect modeling program to allow intergroup comparison. RESULTS: Each agent induced a concentration- and use-dependent slowing of conduction velocities, with no change of the anisotropic ratio. The use-dependent effect of levobupivacaine is similar to that of racemic bupivacaine concerning longitudinal conduction velocity. Fitting of conduction velocities provided a racemic bupivacaine to levobupivacaine and to ropivacaine ratio of 1:1.38 for concentration effect at 1,000-ms pacing cycle length, and 1:0.74 for use-dependent effect at 600-ms pacing cycle length. Racemic bupivacaine and levobupivacaine prolonged the ventricular effective refractory period, whereas ropivacaine did not. No dispersion in ventricular effective refractory period values occurred. All three agents induced significant decreases in wavelengths. This effect was not different among groups. CONCLUSIONS: Differences among racemic bupivacaine, levobupivacaine, and ropivacaine at equimolar concentrations are mainly caused by the use-dependent effects on conduction velocities and the concentration-dependent effects on ventricular effective refractory period. Therefore, one must take into account the corresponding pacing rates when comparing the potency ratios of local anesthetics. 相似文献
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