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We designed a prospective trial to determine the long-term prognosis of video-assisted thoracoscopic (VATS) lobectomy versus conventional lobectomy for patients with clinical stage IA (T1N0M0) lung cancer. Between January 1993 and June 1994, 100 consecutive patients with clinical stage IA non-small cell lung carcinoma underwent either conventional lobectomy through an open thoracotomy (open group; n= 52) or VATS lobectomy (VATS group; n= 48). Lymph node dissections were performed in a similar manner in both groups. No significant differences were observed in the number of dissected lymph nodes between the 2 groups. Pathologic N1 and N2 disease was found in 3 and 1 patients, respectively, from the open group, and in 2 and 1 patients, respectively, from the VATS group. During the follow-up period, distant metastases and local or regional recurrences developed in 7 and 3 of the open group patients, respectively, and in 2 and 3 of the VATS group patients, respectively. Two and one of the open and VATS group patients developed second primary cancers, respectively. The overall survival rates 5 years after surgery were 85% and 90% in the open and VATS groups, respectively (log-rank test, p= 0.74; generalized Wilcoxon test, p= 0.91). VATS lobectomy with lymph node dissection achieved an excellent 5-year survival, similar to that achieved by the conventional approach.  相似文献   
13.
We reported previously that an angiogenesis inhibitor, E7820, inhibits in vitro tube formation of human umbilical vein endothelial cell through the suppression of integrin alpha2 expression. Here we describe the antiangiogenic and antitumor effects of E7820 in mice and discuss the feasibility of using platelet integrin alpha2 expression on platelets as a biological marker of the efficacy of E7820. Oral administration of E7820 significantly inhibited basic fibroblast growth factor-induced angiogenesis in Matrigel implants and human colon WiDr tumor-induced angiogenesis in a dorsal air sac model. Twice-daily treatment with E7820 clearly inhibited the s.c. tumor growth of seven tumor cell lines derived from human colon, breast, pancreas, and kidney, and completely suppressed the growth of human pancreatic KP-1 and human colon LoVo cell lines. Moreover, E7820 significantly inhibited the growth of KP-1 and human colon tumor Colo320DM cells orthotopically implanted in the pancreas and cecum, respectively. The efficacy of E7820 was comparable in the s.c. and orthotopic transplantation models. Immunohistochemical analyses using anti-CD31 antibody showed that E7820 significantly reduced microvessel density in orthotopically implanted KP-1 tumor. E7820 reduced integrin alpha2 expression on a megakaryocytic cell line, Dami cells, induced by phorbol 12-myristate 13-acetate treatment. It also decreased the expression level of integrin alpha2 on platelets withdrawn from mice bearing s.c. KP-1 tumor at a dosage close to that affording antitumor activity. These data demonstrate that E7820 showed a broad-spectrum antitumor effect in mice through inhibition of angiogenesis and indicate that the decrease of integrin alpha2 on platelets might serve as a biological marker for the antitumor efficacy of E7820.  相似文献   
14.
To characterize uremic cardiac autonomic neuropathy, we measured plasma catecholamines, analyzed the 24-hour heart rate variability (HRV), and acquired serial images with (123)I-metaiodobenzylguanidine (MIBG) in 44 patients with chronic renal failure on hemodialysis and in 14 controls. Time-domain measures were calculated using the Marquette HRV program. MIBG clearance rates from the heart and lung were evaluated on planar images, and the regional MIBG uptake in the left ventricular myocardium was evaluated with single-photon emission computed tomography. Compared with controls, plasma dopamine and norepinephrine levels were elevated (p < 0.001 and p = 0.03, respectively), and all the time-domain measures of HRV were reduced in the patients (p < 0.001). The MIBG clearance rate from the heart was higher (p < 0.001), that from the lung was lower (p < 0.001), and the myocardial MIBG distribution was more heterogeneous in patients than in controls (total uptake score p 相似文献   
15.
Brugada syndrome is characterized by right bundle-branch block, ST elevation in leads V 1 through V 3 and normal QT interval. Ventricular fibrillation frequently occurs in patients with Brugada syndrome. There have been few reports of anesthetic management of Brugada patients. We managed a 47-year-old man with Brugada syndrome, who underwent hemilaminectomy under general anesthesia, without untoward cardiovascular events. Potential problems in anesthetic management of patients with Brugada syndrome are also discussed.  相似文献   
16.
OBJECTIVES: We conducted a collaborative cohort study to evaluate the predictive power of microvolt T-wave alternans (TWA) in patients with preserved left ventricular ejection fraction (LVEF) after myocardial infarction (MI). BACKGROUND: There is little information available about the prognostic value of risk stratification markers in this population. Although these patients have a relatively good prognosis, identifying high-risk patients is important in clinical practice. METHODS: This study enrolled 1,041 post-MI patients with an LVEF > or =40% (average 55 +/- 10%). Microvolt TWA testing was performed 48 +/- 66 days after acute MI, and 10 other risk variables were also evaluated. The end points were prospectively defined as sudden cardiac death or life-threatening arrhythmic events. RESULTS: During a follow-up of 32 +/- 14 months, 38 patients (3.7%) died of nonarrhythmic causes and were not considered for analysis. Of the 1,003 evaluable patients, 18 (1.8%) reached an end point. Microvolt TWA was positive in 169 patients (17%), negative in 747 (74%), and indeterminate in 87 (9%). A positive microvolt TWA test, nonsustained ventricular tachycardia, and ventricular late potentials were predictors of events, and percutaneous coronary intervention decreased the risk rate. On multivariate analysis, a positive microvolt TWA test was the most significant predictor, with a hazard ratio of 19.7 (p < 0.0001). This marker had the highest sensitivity and negative predictive value for events. CONCLUSIONS: In patients with preserved cardiac function, the incidence of indeterminate results of microvolt TWA is low, and a positive test result is associated with arrhythmic events. Microvolt TWA could be used for risk stratification in this low-risk population.  相似文献   
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BACKGROUND: To investigate the activation patterns and conduction velocity (CV) in the posterolateral right atrial (RA) wall during typical counterclockwise atrial flutter (AFL) using an electroanatomic mapping system. METHODS AND RESULTS: During typical AFL in 25 patients, the transverse conduction pattern and CV were classified and calculated. The line blocking transverse conduction was defined by the conduction pattern and double potentials recorded during mapping. There were 3 types (including 2 subtypes) of transverse conduction pattern based on the conduction blocks across the posterolateral RA in a line between the superior and inferior venae cava. Trans-cristal conduction activation in a horizontal direction was seen in all but 4 patients. The CV in the gap area was 0.59+/-0.21 m/s. CONCLUSIONS: Three types of transverse conduction pattern were observed during trans-ctristal conduction and the trans-ctristal CV was relatively slower than that in other parts of the RA, except for the isthmus.  相似文献   
19.
Despite >50 years of research work since the discovery of sliding filament mechanism in muscle contraction, structural details of the coupling of cyclic cross-bridge movement to ATP hydrolysis are not yet fully understood. An example would be whether lever arm tilting on the myosin filament backbone will occur in the absence of actin. The most direct way to elucidate such movement is to record ATP-induced cross-bridge movement in hydrated thick filaments. Using the hydration chamber, with which biological specimens can be kept in an aqueous environment in an electron microscope, we have succeeded in recording ATP-induced cross-bridge movement in hydrated thick filaments consisting of rabbit skeletal muscle myosin, with gold position markers attached to the cross-bridges. The position of individual cross-bridges did not change appreciably with time in the absence of ATP, indicating stability of time-averaged cross-bridge mean position. On application of ATP, individual cross-bridges moved nearly parallel to the filament long axis. The amplitude of the ATP-induced cross-bridge movement showed a peak at 5–7.5 nm. At both sides of the filament bare region, across which the cross-bridge polarity was reversed, the cross-bridges were found to move away from, but not toward, the bare region. Application of ADP produced no appreciable cross-bridge movement. Because ATP reacts rapidly with the cross-bridges (M) to form complex (M·ADP·Pi) with an average lifetime >10 s, the observed cross-bridge movement is associated with reaction, M + ATP → M·ADP·Pi. The cross-bridges were observed to return to their initial position after exhaustion of ATP. These results constitute direct demonstration of the cross-bridge recovery stroke.  相似文献   
20.
BACKGROUND: Recent studies have shown that a global flow abnormality affects the entire coronary tree in patients with acute coronary syndrome (ACS), and that it is associated with adverse outcomes. Postprandial hyperglycemia is also thought to promote coronary endothelial dysfunction, as well as the release of inflammatory and vasoconstrictive factors. This study used the corrected Thrombolysis In Myocardial Infarction frame count (CTFC) to investigate whether optimal control of postprandial hyperglycemia improves pan-coronary flow. METHODS AND RESULTS: Eighty ACS patients with postprandial hyperglycemia who had successful coronary intervention and who had undergone a 75-g oral glucose tolerance test (OGTT) were included. A second OGTT and angiogram were performed 8 months after procedures. The patients were divided according to postprandial glycemia after the second 75-g OGTT; optimal postprandial hyperglycemia was defined as a 2-h blood glucose concentration <7.8 mmol/L. Changes in the CTFC of culprit/non-culprit arteries, glucose response, and other clinical variables were compared. Forty patients improved to an optimal control at 8 months. In the culprit artery, the 8-month angiogram revealed a significantly improved CTFC among those with optimal control compared with the initial angiogram (30+/-9 vs 24+/-12, p<0.05). In contrast, the CTFC was not evidently improved among patients with suboptimal control. The CTFC at 8 months had thus obviously improved more in patients with optimal, than with suboptimal control (24+/-12 vs 30+/-11, p<0.05). CONCLUSION: Optimal control of postprandial hyperglycemia improves epicardial blood flow in both arteries and this beneficial effect might be from improved coronary endothelial function.  相似文献   
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