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Objective: Impacts of mediastinal lymph node dissection on a patient’s course after pulmonary resection is unclear in octogenarians with non-small cell lung cancer. Methods: Retrospectively identified subjects included 39 octogenarians and 1 nonagenarian, with grades according to the Charlson Comorbidity Index ranging from only 0 to 2. We performed mediastinal lymph node dissection in 19 patients (D group), and just lymph node sampling biopsy in the other 21 (S group). We compared clinicopathologic features and outcome after surgery between both groups. Results: Deterioration of performance status at the time of discharge, evident in 17 patients overall, was significantly more frequent in the D group. Postoperative complications occurred in 27 patients overall and there was no significant difference between the two groups. Survival rates in younger patients at 1, 3, and 5 years were 86, 59, and 49%, respectively; in octogenarians these were 83, 58, and 42% (no significant difference). Nor did survival differ significantly by surgical management of mediastinal lymph nodes; 1-, 3-, and 5-year survival rates were 94, 63, and 40%, respectively in the D group and 78, 66, and 43%, respectively in the S group. Conclusion: Octogenarians with non-small cell lung cancer should be treated by urgent pulmonary resection whenever possible. Since mediastinal lymph node dissection has little effect on long-term survival or the carried risk of worsening performance status at discharge, pulmonary resection without complete mediastinal lymph node dissection should be considered.  相似文献   
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Acute encephalopathy associated with influenza and other viral infections   总被引:7,自引:0,他引:7  
Acute encephalopathy is the most serious complication of pediatric viral infections, such as influenza and exanthem subitum. It occurs worldwide, but is most prevalent in East Asia, and every year several hundreds of Japanese children are affected by influenza-associated encephalopathy. Mortality has recently declined, but is still high. Many survivors are left with motor and intellectual disabilities, and some with epilepsy. This article reviews various syndromes of acute encephalopathy by classifying them into three major categories. The first group caused by metabolic derangement consists of various inherited metabolic disorders and the classical Reye syndrome. Salicylate is a risk factor of the latter condition. The second group, characterized by a systemic cytokine storm and vasogenic brain edema, includes Reye-like syndrome, hemorrhagic shock and encephalopathy syndrome, and acute necrotizing encephalopathy. Non-steroidal anti-inflammatory drugs, such as diclofenac sodium and mephenamic acid, may aggravate these syndromes. Severe cases are complicated by multiple organ failure and disseminated intravascular coagulation. Mortality is high, although methylprednisolone pulse therapy may be beneficial in some cases. The third group, characterized by localized edema of the cerebral cortex, has recently been termed acute encephalopathy with febrile convulsive status epilepticus, and includes hemiconvulsion-hemiplegia syndrome and acute infantile encephalopathy predominantly affecting the frontal lobes. Theophylline is a risk factor of these syndromes. The pathogenesis is yet to be clarified, but an increasing body of evidence points to excitotoxicity and delayed neuronal death.  相似文献   
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Fluctuating PEEP (F-PEEP) is a newly developed PEEP in which end-expiratory pressure (EEP) is periodically changed within a certain range. In a dog model with unilateral lung injury induced by the introduction of hydrochloric acid, F-PEEP in which the EEP was periodically changed from 0.5 to 1.5 kPa at periods of 6 min, and conventional PEEP (C-PEEP) with an optimized EEP of 1.0 kPa, were each applied for 30 min. F-PEEP produced a significantly greater improvement of PaO2 and intrapulmonary shunt (QS/QT) than C-PEEP, and at the low EEP phase, the greatest improvement accompanied by an increased dynamic compliance and a large cardiac output was obtained. These results suggest that F-PEEP provides a useful mode of artificial ventilation for the treatment of unilateral lung injury.  相似文献   
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The effect of sevoflurane on diaphragmatic contractility was investigated in 12 anesthetized, mechanically ventilated dogs with the thorax opened. Animals were divided into two groups of six each: the sevoflurane and time control groups. We assessed contractility by the transdiaphragmatic pressure (Pdi) during supramaximal stimulation of the phrenic nerve at frequencies of 0.5, 10, 20, 50, and 100 Hz under quasiisometric conditions. The integrated electrical activity (Edi) of the crural and costal parts of the diaphragm (Edi cru, Edi cost) was also measured. In the sevoflurane group, diaphragmatic contractility was determined during three levels of anesthesia, specifically 0, 1.0, and 1.5 minimum alveolar anesthetic concentration (MAC). Measurements were made at the start of the stimulation (initial) and at the end of the 2-s period (2-s). Increasing the depth of sevoflurane anesthesia did not cause any significant differences in Pdi and Edi at 0.5-, 10-, and 20-Hz stimulation. By contrast, at 50- and 100-Hz stimulation, initial Pdi during 1.0 and 1.5 MAC sevoflurane exposure decreased significantly compared with the 0 MAC value (P less than 0.05). In addition, there was a statistical difference in 2-s Pdi between 1.0 and 1.5 MAC at 100-Hz stimulation (P less than 0.05). The Edi cru showed similar changes in Pdi at both measurements, whereas there was no remarkable change in Edi cost. There was no significant change either in Pdi or in Edi with respect to time in the time control group. We conclude from these results that sevoflurane impairs diaphragmatic contractility through its inhibitory effect on neuromuscular transmission, predominantly of the crural part.  相似文献   
7.
We report the case of a 67-year-old woman with severe hypertension caused by an extra-adrenal pheochromocytoma. The tumor was detected by 131I metaiodobenzylguanidine scintigraphy and it was found to be small (2 cm ?) by enhanced CT. After the extirpation of the tumor, the blood pressure of the patient immediately normalized. It should be taken into account that a small extra-adrenal pheochromocytoma can be one of the causes of secondary hypertension in elderly patients. Since small extra-adrenal pheochromocytomas are difficult to detect, it is also important to perform suitable examinations to establish the diagnosis. Furthermore, we emphasize the importance of an accurate diagnosis in elderly patients with pheochromocytoma, for they often have less symptomatology and more severe cardiovascular complications due to refractory hypertension than younger patients.  相似文献   
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We examined the effects of angiotensin II (Ang II) on inward rectifier K+ currents (IK1) in rat atrial myocytes. [125I]Ang II-binding assays revealed the presence of both Ang II type 1 (AT1) and type 2 (AT2) receptors in atrial membrane preparations. Ang II inhibited IK1 in isolated atrial myocytes with an IC50 of 46 nmol/l. This inhibition was abolished by the AT, antagonist RNH6270 but not at all by the AT2 antagonist PD123319. Treatment of cells with pertussis toxin or a synthetic decapeptide corresponding to the carboxyl-terminus of Gialpha-3 abolished the inhibition by Ang II, indicating the role of a Gi-dependent signaling pathway. Accordingly, Ang II failed to inhibit IK1 in the presence of forskolin, dibutyryl-cAMP or protein kinase A catalytic subunits. In spite of the increased binding capacities for [125I]Ang II, Ang II failed to affect IKI in cells from spontaneously hypertensive rats (SHR). AT, immunoprecipitation from atrial extracts revealed decreased amounts of Gialpha-2 and Gialpha-3 proteins associated with this receptor in SHR as compared with controls. The reduced coupling of AT, with Gialpha. proteins may underlie the unresponsiveness of atrial IK1 to Ang II in SHR cells.  相似文献   
10.
Pulmonary hamartoma is a common benign neoplasm that is usually asymptomatic and that arises in the periphery of the lung. However, when the tumor is growing without showing characteristic findings of hamartoma, such as involving calcification, fat density, and chondromatous contents in chest X-rays or computed tomography, the diagnosis is sometimes that problematic and definitive histological diagnosis should be established. We herein report a case with a massive hemoptysis 10 days after a successful transbronchial biopsy. A 69-year-old man who underwent mitral valve plasty 6 years earlier presented a left lung shadow during a routine chest X-ray. The shadow was seen to be growing by a series of chest X-rays. A week after warfarin had been stopped, a bronchoscopic biopsy was performed. No bronchial hemorrhage was observed during the procedure, and warfarin was not restarted. The patient began noticing bloody sputa once or twice a day, and 10 days after the biopsy, 400 mL of hemoptysis was suddenly disgorged. An emergency left upper lobectomy of the lung was performed, and the hemoptysis soon disappeared postoperatively. The patient is well without respiratory symptoms 36 months after the surgery.  相似文献   
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