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131.
Metabolism is one of the major determinants for age-related changes in susceptibility to chemicals. Aldehydes are highly reactive molecules present in the environment that also can be produced during biotransformation of xenobiotics and endogenous metabolism. Although the lung is a major target for aldehyde toxicity, early development of aldehyde dehydrogenases (ALDHs) in lung has been poorly studied. The expression of ALDH in liver and lung across ages (postnatal day 1, 8, 22, and 60) was investigated in Wistar-Han rats. In adult, the majority of hepatic ALDH activity was found in mitochondria, while cytosolic ALDH activity was the highest contributor in lung. Total aldehyde oxidation capability in liver increases with age, but stays constant in lung. These overall developmental profiles of ALDH expression in a tissue appear to be determined by the different composition of ALDH isoforms within the tissue and their independent temporal and tissue-specific development. ALDH2 showed the most notable tissue-specific development. Hepatic ALDH2 was increased with age, while the pulmonary form did not. ALDH1 was at its maximum value at postnatal day 1 (PND1) and decreased thereafter both in liver and lung. ALDH3 increased with age in liver and lung, although ALDH3A1 was only detectible in lung. Collectively, the present study indicates that, in the case of aldehyde exposure, the in vivo responses would be tissue and age dependent.  相似文献   
132.
The intercostal hernia of the lung is a very rare extraordinary disease that requires operation because of the complaints and potential complications. The authors review cases of their operations and analyze the subsequence and treatment. Three patients have been treated for intercostal lung hernia in our treatment. The causes of this disease were a previous thoracotomy in one case and fits of coughing in the other two cases. The diagnosis was set up on the grounds of the specific clinical symptoms, thoracic X-ray and CT scan. The hernia was dissolved with percostal stitches and with the suture of the thoracic musculature in two cases. Plastic operation of the thoracic wall by implanting a polypropylene surgical mesh (Prolen, Ethicon, Johnson & Johnson) was performed in the case of the third patient and later in the first two patients due to recrudescence. In one case the authors were constrained to resect the dystelectasial lung in the hernial sac. The three patients had been operated five times. Relapse of hernia was detected in two patients, in whom the intercostal space had been reconstructed with percostal stitches. We did not detect any relapsing in those two patients at 33 and 66 months after the second operation with mesh implantation. The third patient who got mesh implant immediately did not relapse 12 months after the operation. Intercostal lung hernia is an indication of operation. A plastic operation of the thoracic wall combined with the implantation of a surgical mesh is recommended to close the hernial orifice, which is suitable for treating both primary and relapsed hernias. Recurrence is rare in those patients treated with this method.  相似文献   
133.
The case of a 75-year-old man with three synchronous carcinomas of the lung (large cell carcinoma, adenocarcinoma, and small cell carcinoma) is reported. This is the eighth well-documented case report in the literature; however, our case is the first to be reported with the newly described histological combination.  相似文献   
134.
We present herein the rare case of a young man who was found to have a solitary tumor in the right upper lobe of his lung by a routine chest X-ray. The tumor was removed by thoracoscopic surgery, and pathological examinations confirmed the diagnosis of a primary lymphangioma of the lung. A brief review of the available literature on this extremely rare type of benign tumor follows the case report.  相似文献   
135.
三种卷烟的成分及其对健康的影响   总被引:4,自引:1,他引:3  
本文分析了我国高、中、低三种卷烟的成分、致突变性和对人体健康的影响。结果表明,高焦油卷烟含焦油、BaP 和重金属元素均高于中、低焦油的卷烟,其焦油有致突变作用。吸烟者吸三种卷烟后能引起气道阻力。血中COHb%和尿中柯的宁等指标明显升高。吸烟者吸烟时可使其被动吸烟者的COHb%浓度均达有害程度。  相似文献   
136.
Clusterlike Headache as a First Sign of Brain Metastases of Lung Cancer   总被引:1,自引:0,他引:1  
Dr.  J. Tajti  MD  PhD ; Dr.  K. Sas  MD ; Dr.  D. Szok  MD ; Dr.  E. Vörös  MD ; Dr.  L. Vécsei  MD  DSc 《Headache》1996,36(4):259-260
We report on a patient with clusterlike headache and multiple brain metastases of lung cancer. Initially, cluster headache was suggested clinically by characteristic symptoms without any focal central nervous system signs. However, magnetic resonance imaging demonstrated multiple brain metastases. It is possible that tumor necrosis factor may have played a role in initiating the clusterlike headache.  相似文献   
137.
Activity of succinic dehydrogenase(SDH)and acid phosphatase(AcPase)of effector-target cells during the process of LAK cells killing HR8348 cells was estimated by enzyme cyto-chemistry technique.SHD positive granules and AePase gray level were assayed with MIAS-300image analyser.The results showed:(1)After cocultivation of effector and target cells for vari-ous times,the activity of AcPase of HR8348 cells was apparently higher than that of the controlgroup,and it increased following prolonged coincubation.SDH activity of target cells increasedmarkedly within 30 and 60 rain cocultivation,but became low after 90 min treatment.(2)Ac-Pase content within LAK cells at 60,90,120,180 and 240 rain cocultivation was significantlyhigher than that of control group(P<0.01).The phenomenon of high AcPase and SDH activitywithin effector-target cells indicates that the function of the two types of cells was in an activestate.At the early stage of effector-target combining,the increase of SDH with HR8348 cellsmay be related to defensive function of the target cells.Higher AcPase activity of target cells in-dicates the activation of lysosomal enzyme which serves as the material basis for autolysis of thecells.  相似文献   
138.
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   
139.
140.
胃癌D17S261和D17S799位点二核苷酸重复序列不稳定性的意义   总被引:2,自引:2,他引:0  
目的研究二核苷酸重复序列不稳定性〔DRSI〕在胃癌发生中的作用及其临床意义.方法采用PCR方法检测了D17S261和D17S799位点二核苷酸重复序列不稳定性.结果胃癌总DRSI发生率为34%(17/50),其中高中分化腺癌DRSI阳性率(667%,10/15)显著高于低分化癌(194%,6/31,P<001);肠型胃癌DRSI阳性率(556%,10/18)显著高于胃型胃癌(20%,6/30,P<005),DRSI与胃癌部位、大小、浸润、分期、淋巴结转移无显著相关.结论DRSI在胃癌的发生中可能起重要作用.  相似文献   
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