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991.
Pulmonary metastasis is frequently seen in patients with advanced hepatocellular carcinoma. However, information is limited concerning life-threatening complications and effective treatment of pulmonary metastasis because of the poor prognosis of patients with advanced hepatocellular carcinoma. Recent remarkable progress in detection and treatment of hepatocellular carcinoma has improved prognosis, making management of pulmonary metastasis an important clinical issue. We describe a 68-year-old man with pulmonary metastasis of hepatocellular carcinoma and sudden onset of hemoptysis from bronchial invasion. Transcatheter embolization was performed successfully via the bronchial artery with disappearance of bloody sputum. Peribronchial pulmonary metastasis of hepatocellular carcinoma can cause life-threatening hemoptysis. Transcatheter arterial embolization may be one of therapeutics for hemoptysis from invasive pulmonary metastasis of hepatocellular carcinoma.  相似文献   
992.
C-type natriuretic peptide (CNP) has been shown to act as a local regulator of vascular tone and remodeling. We investigated whether CNP ameliorates monocrotaline (MCT)-induced pulmonary hypertension in rats. Rats received a continuous infusion of CNP or placebo. Significant pulmonary hypertension developed 3 weeks after MCT. However, infusion of CNP significantly attenuated the development of pulmonary hypertension and vascular remodeling. Neither systemic arterial pressure nor heart rate was altered. Interestingly, CNP enhanced Ki-67 expression, a marker for cell proliferation, in pulmonary endothelial cells and augmented lung tissue content of endothelial nitric oxide synthase. CNP significantly suppressed apoptosis of pulmonary endothelial cells, decreased the number of monocytes/macrophages, and inhibited expression of plasminogen activator inhibitor type 1, a marker for fibrinolysis impairment, in the lung. In addition, CNP significantly increased the survival rate in MCT rats. Finally, infusion of CNP after the establishment of pulmonary hypertension also had beneficial effects on hemodynamics and survival. In conclusion, infusion of CNP ameliorated MCT-induced pulmonary hypertension and improved survival. These beneficial effects may be mediated by regeneration of pulmonary endothelium, inhibition of endothelial cell apoptosis, and prevention of monocyte/macrophage infiltration and fibrinolysis impairment.  相似文献   
993.
We report two cases of intralobar pulmonary sequestration associated with nontuberculous mycobacterial infection. Case 1: A 28-year-old woman was hospitalized because of cough. Chest CT demonstrated multi-cystic lesions with an air-fluid level in the right lower lobe. Case 2: A 25-year-old woman was hospitalized because of fever. Chest CT demonstrated homogeneous consolidation in the right lower lobe. In both cases, aortography showed an anomalous artery supplying the right basal segment, and pulmonary sequestration was diagnosed. Furthermore, Mycobacterium avium was detected in the bronchial lavage, and a right lower lung lobectomy was performed after chemotherapy. Mycobacterium avium was cultured from the fluid in the sequestrated lung, and histological findings of the resected lobe showed epithelioid cell granulomas. We diagnosed these cases as having pulmonary sequestrations associated with nontuberculous mycobacterial infection. We concluded that pulmonary sequestration should be considered an underlying disease of secondary nontuberculous mycobacterial infections in young patients.  相似文献   
994.
Phospholipase A2 activity and prostaglandin synthesis were studied in the renal cortex and medulla of stroke-prone spontaneously hypertensive rats (SHRSP) and age-matched normotensive Wistar-Kyoto rats (WKY) aged 10-50 weeks. Enhanced phospholipase A2 activity was found in both the cortical and the medullary microsomes of SHRSP kidneys. Phospholipase A2 activity progressively increased with age in SHRSP, but not in WKY. Prostaglandin E2 (PGE2) and thromboxane A2 (TXA2) were the major prostaglandins found in the cortex, and PGE2 was the major prostaglandin found in the medulla. Prostaglandin l2 (PGI2) was synthesized in both the cortex and medulla, but cortical PGI2 synthesis was much lower than medullary synthesis. Enzymatic activity for all prostaglandin syntheses analysed here were higher in SHRSP. There was a greater age-related increase in prostaglandin synthesis in SHRSP kidneys than in WKY kidneys. In addition, the ratios of PGE2/TXB2 and 6-keto-prostaglandin F1 alpha (PGF1 alpha)/thromboxane B2 (TXB2) decreased in SHRSP. This may produce vasoconstriction and increase vascular resistance in SHRSP. These data suggest that increased prostaglandin synthesis and phospholipase A2 activity have an important role in the development and maintenance of hypertension in SHRSP.  相似文献   
995.
996.
Patients have been observed with a chest pain syndrome after cardiac transplantation. For this pain to be cardiac in origin the afferent nerves carrying sensory information from the heart would have to reinnervate the heart. A previous study in dogs indicated that afferent reinnervation is uncommon during the first 2 years after transplantation. The purpose of this study was to determine whether afferent reinnervation of the heart occurs in the long term. The decreases in arterial pressure and renal nerve activity resulting from chemical stimulation of left ventricular sensory receptors with vagal afferents with cryptenamine (veratrum alkaloid) were assessed in three dogs 8 to 12 years and in four dogs 6 to 8 weeks after cardiac autotransplantation and in six sham-operated dogs (thoracotomy-pericardiotomy 6 to 8 weeks before study). Responses of renal nerve activity to physiologic stimulation of cardiac receptors by volume expansion were also determined. Left ventricular cryptenamine inhibited renal nerve activity by 72 +/- 8% in dogs with long-term and by 10 +/- 6% in dogs with short-term autotransplantation and by 92 +/- 5% in sham-operated dogs. Decreases in mean arterial pressure in these groups were 34 +/- 4, 11 +/- 3 and 67 +/- 16 mm Hg, respectively. Volume expansion inhibited renal nerve activity in long-term autotransplant (43%) and sham-operated (48%) groups but less in the short-term transplant group (33%) for comparable increases in cardiac filling pressure. It is concluded that in dogs there is extensive afferent reinnervation of the long-term autotransplanted heart that results in relatively normal cardiopulmonary baroreflex responses to volume expansion.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
997.
Effect of atrial natriuretic factor on angiotensin converting enzyme   总被引:1,自引:0,他引:1  
We studied the effects of atrial natriuretic factor (ANF) on the conversion of angiotensin I to angiotensin II. Pulmonary artery endothelial cells converted 1.22 nmol/min per dish [125I]angiotensin I to angiotensin II, but ANF suppressed the conversion by 0.475 nmol/min per dish. The maximum rate of inhibition of angiotensin converting enzyme (ACE) activity by ANF was 60% at 10(-6) mol/l ANF compared with control conditions. The amino acid fragments of ANF were studied to determine whether its specific structure was necessary for inhibiting ACE in endothelial cells. We found that atriopeptin II (fragment 5-27) inhibited ACE activity as much as ANF. Fragment 7-25 had the same rate of inhibition, but fragment 13-27 had no effect on the conversion of angiotensin I to angiotensin II. These results suggest that the amino acid sequence of Cys (7)-Cys (23) in ANF is important for the inhibition of ACE in pulmonary endothelial cells.  相似文献   
998.
Background and aims The purpose of this study was to assess the long-term efficacy of preoperative radiotherapy for locally advanced low rectal cancer. Materials and methods Between April 1990 and June 2005, all patients who underwent surgery for low rectal cancer with a pretreatment diagnosis of T3 or resectable T4 without distant metastasis were enrolled. The total dose of radiation was 45 Gy. Patients with a partial or complete response were defined as radiotherapy responders (RT-R) and the others as radiotherapy non-responders (RT-NR). Patients who did not receive radiotherapy were termed the non-radiotherapy group (NRT). The endpoint of this study was overall survival and local and/or distant metastasis. Results There were 24 patients in RT-R, 26 in RT-NR, and 40 in NRT. Gastrointestinal complications were commonly observed in all groups. RT-R had a significantly higher incidence of genitourinary complications. Five-year overall survival rate was 79.6% in RT-R, 58.9% in RT-NR, and 58.8% in NRT. The difference was significant in favor of RT-R over the others (P = 0.015, 0.024, respectively). Five-year local recurrence-free survival rate was 100% in RT-R, 81.5% in RT-NR, and 74.9% in NRT. RT-R had significantly improved local control compared with the others (P = 0.034, 0.021, respectively). Five-year distant metastasis-free survival was not statistically different among all groups. Conclusions Survival benefit of preoperative radiotherapy was limited to responders. Considering the increased risk of adverse effects, identification of predictors of radiosensitivity is required in order to provide the most suitable treatment for individual patients.  相似文献   
999.
Osteoprotegerin is a circulating osteoclastogenesis inhibitory factor and serum osteoprotegerin levels are elevated in hemodialysis patients. This study investigated whether osteoprotegerin levels correlated with various clinical parameters in hemodialysis patients. The subjects were 45 men and 37 women aged from 27 to 94 years (mean = 60.4 +/- 13.9 years), and the duration of dialysis was 9-277 months (mean = 89.5 +/- 64.7 months). Serum osteoprotegerin levels were measured by enzyme-linked immunosorbent assay. Data were analyzed by stepwise multiple regression analysis. The mean osteoprotegerin level of the hemodialysis patients was 303 +/- 210 pg/mL, which was higher than in age-matched healthy controls. Osteoprotegerin levels increased with age, a longer duration of dialysis, and the presence of diabetes. Skeletal resistance to parathyroid hormone might be increased by aging, a long dialysis period, and diabetes, perhaps explaining why adynamic bone disease is more common in older or diabetic patients.  相似文献   
1000.
Perioperative coronary vasospasm has been recognized as a possible cause of myocardial infarction or low output syndrome after open heart operations. A 57-year-old male suffered cardiogenic shock immediately after off-pump coronary artery bypass grafting surgery. Emergent angiography performed under intraaortic balloon pumping and percutaneous cardiopulmonary support revealed severe multivessel coronary vasospasm which was effectively treated with a high dose intracoronary administration of isosorbide dinitrate. Emergent angiography for patients with cardiogenic shock after open heart operation is feasible and effective for the diagnosis and treatment of perioperative coronary vasospasm.  相似文献   
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