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Varma MR Moaveni DM Dewyer NA Varga AJ Deatrick KB Kunkel SL Upchurch GR Wakefield TW Henke PK 《Journal of vascular surgery》2004,40(3):536-542
INTRODUCTION: Deep venous thrombosis (DVT) resolution involves fibrinolysis, neovascularization, and fibrosis. We hypothesized that promoting neovascularization would accelerate DVT resolution. METHODS: A rat model of stasis DVT was produced with proximal ligation of the inferior vena cava (IVC) and all visible tributaries. One microg of interferon inducible protein (IP-10; angiostatic chemokine), basic fibroblast growth factor (bFGF; pro-angiogenic cytokine), epithelial neutrophil activating protein (ENA-78; pro-angiogenic chemokine), or saline solution control was injected into the IVC after ligation, and then via tail vein injection daily until sacrifice at either 4 or 8 days. Peripheral blood counts were measured, and thrombus weight was recorded at sacrifice. Laser Doppler in vivo imaging was used to estimate post-thrombotic IVC blood flow. Immunohistologic assessment of the thrombosed IVC for polymorphonuclear neutrophils (PMNs), monocytes (ED-1), and laminin (neovascular channels) was performed or the thrombus was separated from the IVC and assayed for keratinocyte cytokine (KC), monocyte chemotactic protein-1 (MCP-1), bFGF with enzyme-linked immunosorbent assay (ELISA), and total collagen with a direct colorimetric assay. RESULTS: Peripheral blood and intrathrombus PMNs and monocytes were not significantly different in the treated or control rats. There were no differences in any measure at 4 days. At 8 days, thrombus neovascularity, but not weight or collagen content, was increased in rats treated with bFGF or ENA-78 compared with control rats (17.6 +/- 0.93, 16.2 +/- 0.97 vs 13.2 +/- 0.79; channels/5 high-power fields (hpf; n = 6-10; P <.05). Post DVT IVC blood flow was significantly increased in bFGF-treated rats but not in rats treated with IP-10 or ENA-78, as compared with control rats. Rats treated with ENA-78 had increased intrathrombus bFGF compared with control rats (85 +/- 27 pg/mg protein vs 20 +/- 6 pg/mg protein; n = 6; P <.05), but other mediators were not significantly different in treated rats compared with control rats. CONCLUSION: Pro-angiogenic compounds increase thrombus neovascularization, but this does not correlate with smaller or less fibrotic DVT. Mechanisms other than neovascularization may be more important to hasten DVT dissolution.Clinical relevance Improved therapy for deep venous thrombosis (DVT) will ideally increase the rate of thrombus dissolution and eliminate the bleeding risks of anticoagulation. This study evaluated promoting DVT neovascularization with angiogenic chemokines, and, while successful by experimental measures, this did not translate into smaller DVT. Solely promoting thrombus neovascularization will not likely speed resolution. 相似文献
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Technetium-99m-sestamibi/pertechnetate subtraction scintigraphy vs ultrasonography for preoperative localization in primary hyperparathyroidism 总被引:2,自引:0,他引:2
Berczi C Mezõsi E Galuska L Varga J Bajnok L Lukács G Balázs G 《European radiology》2002,12(3):605-609
A prospective study was performed to evaluate the efficacy of technetium-99m-sestamibi and technetium-99m-pertechnetate subtraction scanning and US for imaging parathyroid glands in primary hyperparathyroidism. Sixty-three patients were surgically treated for primary hyperparathyroidism (HPT). Preoperative scintigraphy and US were performed in all cases. Bilateral neck exploration was carried out on each patient. Results of radionuclide studies and US were compared with surgical and histological findings. In 57 patients with primary HPT the radionuclide scanning gave true-positive results. Four false-negative and two false-positive scintigrams were obtained. The sensitivity and the positive predictive value (PPV) of scintigraphy were 93 and 97%, respectively. Forty-one cases were correctly localized by the US. Seventeen US results were false negative and five were false positive. The sensitivity and the PPV for US were 71 and 89%, respectively. There was a statistically significant difference between the sensitivity of the scintigraphy compared with the US ( p=0.001). Sensitivities of radionuclide scans and US were higher for adenomas (100 and 83%) than for hyperplastic glands (75 and 40%). The sensitivity of technetium-99m-sestamibi and technetium-99m-pertechnetate subtraction scintigraphy was significantly higher compared with US. This sensitive method could help surgeons in performing a rapid and directed parathyroidectomy. 相似文献
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Inhibition of pancreatic secretory and trophic response to caerulein by the H2-receptor antagonist ranitidine in the rat 总被引:1,自引:0,他引:1
The effect of ranitidine (20 mg . kg-1) and cimetidine (50 mg . kg-1) on pancreatic secretory and trophic responses to caerulein (1 microgram . kg-1) was studied in the rat. Ranitidine or cimetidine were administered alone or combined with caerulein twice a day for 7 days. Saline-treated rats were used as controls. At the end of treatment animals were anesthetized and pancreatic juice was collected for 1 h after intravenous secretin plus CCK-PZ (8 U . kg-1). Afterwards rats were sacrificed and growth and composition of pancreatic tissue were determined. Compared with control (saline) values, volume of pancreatic juice and output of trypsin and amylase were increased by treatment with caerulein. Ranitidine, when given combined with caerulein, completely abolished the secretory response induced by the peptide, whereas it was totally ineffective when given alone. Cimetidine (alone or combined with caerulein) was always ineffective. Caerulein increased pancreatic weight, total pancreatic trypsin, amylase and RNA content. Here again ranitidine, combined with caerulein, abolished almost completely the trophic effect of caerulein on the pancreas, but when given alone it did not influence pancreatic growth and composition. Also in this case, cimetidine was completely inactive. These results suggest that ranitidine affects exocrine pancreas with an action independent of the H2-receptor blockade. 相似文献
35.
The basic principles of the operative treatment of lumbar spondylolisthesis became uniform in the literature in the last years. Authors deal shortly with some questions of the indication and of the preoperative examination and describe shortly the basic principles of the operative treatment (decompression, reduction, stabilization). The operative methods used by them are reported and illustrated (Morscher's "hookscrew" method, fusion according to Harrington-Vidal, Cloward's posterior corpodesis--PLIF--and Steffee's transpedicular system). 相似文献
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Pingitore A Picano E Varga A Gigli G Cortigiani L Previtali M Minardi G Colosso MQ Lowenstein J Mathias W Landi P 《Journal of the American College of Cardiology》1999,34(6):1769-1777
OBJECTIVES: The study compared the prognostic value of dipyridamole and dobutamine stress echocardiography in patients with known or suspected coronary artery disease. BACKGROUND: Extensive information is available on the relative diagnostic accuracy of the two tests assessed in a head-to-head fashion, whereas comparative data on their prognostic yield are largely preliminary to date. METHODS: Dipyridamole (up to 0.84 mg/kg over 10 min) atropine (up to 1 mg over 4 min) (DIP) and dobutamine (up to 40 microg/kg/min)-atropine (1 mg over 4 min) (DOB) stress tests were performed in 460 patients with known or suspected coronary artery disease. Patients were followed up for 38+/-21 months. RESULTS: The DIP was negative in 253 and positive in 207 patients. The DOB was negative in 242 and positive in 218 patients. During the follow-up, there were 80 cardiac events. For all cardiac events, the negative and positive predictive value were 83% and 17% for DOB, 84% and 19% for DIP, respectively (p = NS). Considering only cardiac death, by univariate analysis Wall-Motion Score Index (WMSI) at DIP peak dose (chi-square 13.80, p<0.0002) was the strongest predictor, followed by WMSI DOB (chi2 = 8.02, p<0.004) and WMSI at rest (chi2 = 6.85, p<0.008). By stepwise analysis, WMSI at DIP peak dose was the most important predictor (RR [relative risk] 7.4, p<0.0001). CONCLUSIONS: In patients at low-to-moderate risk of cardiac events, pharmacological stress echocardiography with either dobutamine or dipyridamole allows effective and grossly comparable, risk stratification on the basis of the presence, severity and extension of the induced ischemia. 相似文献
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