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41.
Abstract Controversy continues over the optimal extent of lymphadenectomy (regional versus three-field) for a potentially resectable squamous cell carcinoma in the thoracic esophagus. In the Consensus Conference of the International Society for Diseases of the Esophagus (ISDE), held in Munich in 1994, the types of lymphadenectomy were classified as standard, extended, total, or three-field lymphadenectomy. The objective of the present study was to determine the optimal procedure among these four types of lymphadenectomy. The mortality and morbidity rates, postoperative course, and survival rates were compared among 302 patients who underwent curative (R0) transthoracic esophagectomy with one of these four types of lymphadenectomy at Kurume University Hospital, Fukuoka, Japan, from 1986 to 1998. Three-field lymphadenectomy resulted in better survival than any other type of lymphadenectomy for patients with positive lymph node metastasis from a cancer in the upper or middle thoracic esophagus. A postoperative complication, such as recurrent laryngeal nerve paralysis, anastomotic leakage, and tracheal ischemic lesion, was significantly more common after three-field lymphadenectomy. However, the mortality rate was the same among the four procedures. Three-field lymphadenectomy was optimal for an upper or middle thoracic esophageal cancer with metastasis in the lymph node(s) based on improved long-term survival, whereas there was not a large difference in short-term and long-term outcomes after the four types of lymphadenectomy for a lower thoracic esophageal cancer. Electronic Publication  相似文献   
42.
PURPOSE: To describe the ophthalmoscopic and optical coherence tomographically determined retinovitreous interface before and after the development of a macular hole secondary to an accidental laser injury. DESIGN: Observational case report. METHODS: Ophthalmoscopic and optical coherence tomography (OCT) findings in a 53-year-old man were evaluated before and after the macular hole formation secondary to a laser injury. Visual function was followed for 9 months after surgery. RESULTS: A 53-year-old man sustained injury to his right eye by a Ti: Sapphire laser. On the following day, his corrected visual acuity was 0.3, and a small pigment epithelial atrophy was present in the right foveal area. No macular hole was detected by OCT and the retinovitreal interface was normal. Fifty-three days later, a full-thickness macular hole appeared, and no posterior vitreous detachment was detected by OCT. The hole was closed by surgery with final best-corrected visual acuity of 0.7. CONCLUSIONS: Macular holes can develop without visible traction on the retina and can occur long after retinal injury.  相似文献   
43.
The purpose of this study was to analyze long-term follow-up information from patients treated with stenting for unprotected left main coronary artery (LMCA) stenosis. Stenting of unprotected LMCA stenosis is often performed in selected patients, but the long-term safety of this therapy is not yet established. Between January 1995 and September 2000, 270 consecutive patients with unprotected LMCA stenosis and normal left ventricular function who underwent treatment at 4 clinical centers were included in this study. Data were forwarded to the coordinating center using a standard case report form. The procedural success rate was 98.9%. There were no deaths, 3 stent thromboses, and 3 Q-wave myocardial infarctions during the hospitalization. Angiographic follow-up was performed in 237 patients (follow-up rate 87.8%), and the restenosis rate was 21.1%. The reference size was an independent predictor of binary restenosis (odds ratio 0.543, 95% confidence interval 0.308 to 0.957, p = 0.03). During the follow-up period (32.3 +/- 18.5 months), there were 20 deaths (8 cardiac, 12 noncardiac) and 5 nonfatal myocardial infarctions. Target and new lesion revascularizations were required in 45 (16.7%) and 31 (11.5%) patients, respectively. The cumulative probabilities free from major adverse cardiac events were 81.9 +/- 2.4%, 78.4 +/- 2.6%, and 77.7 +/- 2.7%, respectively, at 1, 2, and 3 years. Combined coronary artery disease and postprocedural minimal luminal diameter were the significant predictors of major adverse cardiac events. Thus, the long-term prognosis of patients after stenting of unprotected LMCA stenosis was favorable in selected patients with normal left ventricular function.  相似文献   
44.
Conventional anticoagulation for symptomatic pulmonary embolism consists of continuous intravenous unfractionated heparin as a "bridge" to oral anticoagulation. This strategy requires 5 days or more of intravenous heparin while oral vitamin K antagonists gradually achieve a therapeutic effect. Oral vitamin K antagonists require frequent blood testing to optimize dosing, and their interactions with other medications and foods make regulation difficult. Therefore we tested a different approach to therapy: long-term enoxaparin monotherapy. We randomized 60 symptomatic pulmonary embolism patients in a 2:1 ratio to 90 days of enoxaparin as monotherapy without warfarin (N=40) or to intravenous unfractionated heparin as a "bridge" to warfarin, target INR 2.0-3.0 (N=20). Enoxaparin patients received 1 mg/kg twice daily for 14 days during the acute phase followed by randomized assignment during the chronic phase to 1.0 mg/kg vs. 1.5 mg/kg once daily. In an intention-to-treat analysis, 3 of the 40 enoxaparin patients developed recurrent venous thromboembolism compared with 0 of 20 standard therapy patients (p = 0.54). One of the 40 enoxaparin patients had a major hemorrhagic complication compared with 2 of the 20 standard therapy patients (p = 0.26). Median hospital length of stay was shorter with enoxaparin compared to standard therapy (4 vs. 6 days) (p = 0.001). Following our study we can conclude that extended 3-month treatment with enoxaparin as monotherapy for symptomatic, acute pulmonary embolism is feasible and warrants further study in a large clinical trial.  相似文献   
45.
The time-dependent promotion activity of 17beta-estradiol (E2) by initiation with N-ethyl-N-nitrosourea (ENU) on induction of mouse uterine endometrial proliferative lesions was examined. Illumination-induced persistent estrous female CD-1 mice were divided into five groups at 9 weeks of age. At 10 weeks of age, mice in all groups (n=25) were given a single intra-uterine administration of ENU (50 mg/kg), dissolved in polyethylene glycol. Animals in Groups 2 to 5 were then implanted s.c. with an E2 pellet at 9, 11, 14 and 17 weeks of age. The implants were left in place for 8 weeks and then taken out. At the termination of the experiment (week 15 after the ENU-treatment), all surviving mice were killed and the development of uterine proliferative lesions were assessed. All groups demonstrated endometrial hyperplasias and adenocarcinomas and the incidences of the latter in ENU plus E2 treated animals (Groups 2 to 5; 36, 48, 35 and 36%, respectively) were significantly higher compared to 8% for Group 1, without any variation with the age at E2 treatment. However, the incidences of adenocarcinomas plus severe hyperplasias increased from Groups 1 to 5 (28, 40, 56; P<0.05, 61; P<0.05 and 80%; P<0.01, respectively), indicating that promotion effects of E2 on induction of uterine proliferative lesions in the uterine endometrium become more pronounced with the interval after ENU initiation.  相似文献   
46.
The authors report a case of Budd-Chiari syndrome treated by percutaneous transluminal angioplasty (PTA). In this case, the occlusion of three major hepatic veins with a big collateral to the inferior vena cava via the right inferior hepatic vein (RIHV) and stenosis of the ostium of RIHV were seen. We performed successful PTA of this stenosis.  相似文献   
47.
Current findings suggest that the efficacy of thrombolytic therapy may be limited by the availability of active forms of plasminogen at the thrombus site. The purpose of this study was to determine if the systemic administration of 0.5 mg kg-1 glu-plasminogen (glu-plg) or 0.5 mg kg-1 lys-plasminogen (lys-plg) could safely increase the efficacy of a single intravenous bolus injection of 50,000 U kg-1 prourokinase (proUK) in a dog model of arterial thrombosis. Thrombolysis was measured by monitoring the continuous decrement of 125I-gamma emissions from a radiolabeled thrombus. Reflow was evaluated by direct visual examination. Forty dogs (mean wt 10.3 +/- 2 kg) were randomly sorted into 4 groups of 10 each. The dogs in each group were given either saline plus saline, saline plus proUK, glu-plg plus proUK, or lys-plg plus proUK 60 minutes after formation of an occlusive arterial thrombus. Ninety minutes after drug administration the dogs receiving saline plus proUK, glu-plg plus proUK, and the lys-plg plus proUK showed greater thrombolysis (41%, 43%, and 66%, respectively) than the control (saline plus saline) group (15%, P less than 0.01). The lys-plg plus proUK treatment caused greater lysis than the saline plus proUK or the glu-plg plus proUK treatment (P less than 0.05). All of the dogs (10/10) receiving lys-plg plus proUK had patent vessels at the end of the 90 minute monitoring period, whereas only 4/10 and 5/10 vessels were patent in the saline plus proUK and glu-plg plus proUK groups, respectively. None of the dogs in the saline plus saline group had patent vessels. No significant changes were observed in the various coagulation parameters tested for any of the 4 treatment groups. The results show that lys-plg can safely increase the thrombolytic efficacy of proUK.  相似文献   
48.
49.
The disposition kinetics of O-butyryl propranolol (butyryl-PL), a model compound containing an ester moiety, after intravenous administration was compared with that of PL in rats and beagle dogs. Rats showed only 30% conversion of butyryl-PL to PL up to 2 h after dosing, whereas dogs showed nearly complete conversion within 10 min after administration. The CL(total) of butyryl-PL in rats was 5.8 l/h/kg and that in dogs was 65.6 +/- 18.6 l/h/kg, both of which were greater than hepatic blood flow. The in vivo conversion from butyryl-PL to PL in the rat could be explained on the basis of the hydrolysis characteristics in the liver and blood. The in vitro hydrolysis data and the in vivo data after intra-arterial administration clearly demonstrated that the extremely high CL(total) of butyryl-PL in dogs was dependent on first-pass hydrolysis in the lung in addition to hydrolysis at a blood flow-limited rate in the liver and kidney. The availability of butyryl-PL after passage through the lung was 50%. Furthermore, the isoform of carboxylesterase involved in the pulmonary hydrolysis of butyryl-PL in the dog was identified as D1, a CES-1 group enzyme. However, butyryl-PL was not recognized as a substrate by CES-1 family carboxylesterases, which are present at high levels in the rat lung (RH-1) and kidney (RL-1). These findings indicate that extrahepatic metabolism, especially in the lung, is important in the disposition of drugs containing an ester moiety after intravenous administration and that the substrate specificity of carboxylesterase isozyme distinguishes from others.  相似文献   
50.
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