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61.
The inducibility of sister chromatid exchanges (SCEs) by benzo(a)pyrene (BP) was studied in cultured peripheral blood lymphocytes of 15 untreated lung cancer patients and 25 healthy persons including 11 high- and 14 low-cancer-risk individuals tentatively classified by the familial history of lung cancer and other neoplasms. The baseline SCE frequency in cultured lymphocytes was significantly high in lung cancer patients, as compared with all healthy persons or low-cancer-risk individuals. Following exposure to BP, the lymphocytes of lung-cancer patients and high-cancer-risk individuals exhibited significantly greater SCE yields than those of persons at low risk, although no significant difference was observed in the lymphocyte SCE yields when the levels of lung cancer patients were compared with those of all healthy persons. A comparison of the net SCE increase (delta SCE) in BP-exposed lymphocytes among the study groups, however, revealed a significant difference in delta SCE values only between high- and low-cancer-risk individuals. The present findings on both the observed SCE yields and delta SCE values suggest that lymphocytes of high-risk individuals may be more susceptible to BP-induced DNA damage than those of persons at low risk, and that such a chromosomal hypersensitivity to genotoxins may be associated with a high risk of neoplasms.  相似文献   
62.
目的:研究阈值下经瞳孔温热疗法(TTT)对视网膜组织学的效应。方法:对正常视网膜色素的兔眼进行TTT,通过1个810nm激光二极管产生直径为1.2mm能量为50mW的光斑,持续时间为15、30和60秒。4周后进行荧光血管造影并摘除眼球,通过电子显微镜和免疫组化染色来检查。  相似文献   
63.
64.
Our basic techniques for the management of difficult cases of laparoscopic cholecystectomy (LC) are presented in this article. If access to Calot's triangle cannot be gained safely, dissection should be started at the fundus or body of the gallbladder (GB), rather than the neck (fundus-first method). In cases with a short and wide cystic duct, a transfixing suture should be applied for ligation instead of clipping. EndoGIA is useful for ligating and transecting this case to avoid a subsequent stricture caused by normal method of ligation. Intraoperative cholangiography should be performed near the neck of the GB in cases in which orientation is lost during dissection. More dissection should be performed in the direction of the junction of the bile ducts after orientation is regained. In cases with GB filled with stones accompanied by severe fibrosis, part of the GB is incised to remove the stones and expose the lumen of the GB. Confluence stones can be removed by placing an incision on the GB side of the junction of the duct. The incised part is closed with suture. A cystic tube (C-tube) is placed in the common bile duct through the cystic duct for decompression. In more difficult cases in which dissection cannot be started safely at any location, the body and the fundus of the GB are excised, and a drain is placed at the neck of the GB. Dissection can be carried out from the main surgeon's or the assistant's side depending on the situation, and cooperation between the two surgeons is mandatory to achieve safe LC in difficult cases. When performing the LC, one must have a low threshold for converting to open surgery if injuries cannot be managed safely.  相似文献   
65.
The dynamic responses of minute ventilation, heart rate, cardiac output, oxygen uptake, and carbon dioxide output to cyclic ramp exercise were studied on six healthy male subjects. Exercise was performed in the sitting position using a cycle ergometer. On separate occasions, three different ramp slopes, i.e. 33.3 (repeated for three cycles), 20 (two cycles), and 14.3 W/min (one cycle), were applied over the load range from 0 to 100 W. Mean response times (MRTs) were determined by adopting an exponential function with a time delay to the transient responses. The MRTs of the ascending phase of the first cycle were elongated with a decreasing ramp slope in almost all variables, while those for the descending phase remained unchanged. This resulted in notable asymmetry of the responses in the first cycle. However, there was negligible asymmetry observed in subsequent cycles and the MRTs gradually attained their proper values. Asymmetry in cardiac output was less noticeable compared with that of the respiratory variables. The correlation between the MRTs for ventilation and carbon dioxide output was highly significant, suggesting that a cardiodynamic or humoral mechanism may be related to this phenomenon.  相似文献   
66.
One hundred and one cases of bronchoplasty for primary lung cancer   总被引:1,自引:0,他引:1  
The results of 101 consecutive bronchoplasties performed between 1979 and 1993, including 8 cases of pneumonectomy, 88 cases of lobectomy, 3 cases of segmentectomy, and 2 cases of bronchial resection, are herein reported. Squamous cell carcinoma was the most common disease (59%) followed by adenocarcinoma (30%) and other diseases (11%). Anastomosis was satisfactory in 96 cases. Among the five stenosed cases, local recurrence was found in two cases, and there were three benign strictures. Two of the three benign strictures were treated with bouginage. The pulmonary artery was concomitantly reconstructed in seven cases with satisfactory results. Preoperative chemoradiotherapy was performed in 15 advanced cases and was followed by acceptable surgical results. The 5-year survival rate, according to the post-operative staging of the 86 patients without induction therapy, was 86% in stage I (19 patients), 49% in stage II (21 patients), and 27% in stage IIIA (40 patients). The overall survival rate was 46% at 5 years. There were two indications for this procedure i.e., a positive resection margin in 59 cases and positive hilar nodes in 42 cases. Better survival was noted in patients with squamous cell carcinoma, stage I, and surgery was thus selected for a positive resection margin, and not for a positive node.  相似文献   
67.
A 68-year-old woman was admitted with cough and dyspnea. Her chest X-ray showed right pleural effusion and a mediastinal tumor. She underwent mediastinotomy following a preoperative diagnosis of invasive thymoma. A tumor originating from the thymus had invaded the right middle lobe and pericardium, and multiple pleural dissemination was also found. Therefore, considering the patient's age and pulmonary function, we performed only subtotal resection of the tumor. The pathological diagnosis was poorly differentiated squamous cell carcinoma. The patient received irradiation and chemotherapy including Cisplatin after surgery, but she died 1 year later because of rapid progression of distant metastases.  相似文献   
68.
BACKGROUND: Snoring and obstructive sleep apnoea (OSA) are worse or may only occur in the supine position. The effect of body position on upper airway size has been reported, but the effect on tongue posture has not previously been examined. METHODS: Detailed measurements were made of tongue posture from upright and supine lateral cephalograms on 24 men with OSA and 13 men with non-apnoeic snoring matched for age, body mass index, and craniofacial skeletal pattern. Patients with OSA had apnoea/hypopnoea indices (AHI) of > 50/hour and/or apnoea indices (AI) of > 25/hour while non-apnoeic snorers had AHI of < 10/hour and AI of < 5/hour. RESULTS: In non-apnoeic snorers the tongue depth measurements for the superior-posterior portion of the tongue were larger in the supine than in the upright position (p < 0.05). There was no significant difference in tongue depth measurements between the upright and the supine position in the patients with OSA. CONCLUSIONS: When awake patients with OSA move from the upright to the supine position they maintain their upright tongue posture which may tend to protect against upper airway collapse secondary to the increased gravitational load on the tongue. In contrast, when awake non-apnoeic snorers move from the upright to the supine position a significant dorsal movement in the superior-posterior portion of the tongue is observed.


  相似文献   
69.
The biodistribution and imaging characteristics of the 111In-labeled anti CEA monoclonal antibody ZCE-025 were studied in five patients with suspicion of colorectal carcinoma. Evaluation included antibody pharmacokinetics and assessment of antibody distribution in surgical specimen, making a comparison with whole-body imaging with a gamma camera. ZCE-025 localization in tumors was demonstrated by gamma-camera imaging in 4 of the 5 patients, corresponding to surgical findings. Persistent accumulation of 111In in the lymph nodes was observed in one patient, whereas surgical exploration of these lymph nodes showed no gross or microscopic evidence of metastases of colon carcinoma. Analysis of individual plasma by size exclusion HPLC showed two radioactivity peaks, labeled antibody and free DTPA. No transchelation of 111In to circulating transferrin was observed. The blood clearance was fitted to a two-compartment equation and its half-lives were found to be 10.8 +/- 8.7 h and 69.5 +/- 21.8 h for t1/2 alpha and t1/2 beta, respectively. Total urinary excretion averaged 0.3% of the injected dose/h with a small patient to patient variation. At 24 hrs postadministration the predominant radiolabeled species in urine was free DTPA. Thereafter, radioactivity in urine was partly present as a low molecular weight catabolic product. No apparent correlation between CEA content and uptake of 111In-ZCE-025 in tumors resected by surgery could be found. How 111In-labeled antibody is accumulated into tumors as well as into some nontumor tissues needs further study.  相似文献   
70.
In embryology, a persistent connection of the left superior vena cava to the left atrium rarely coexists with a coronary sinus. We herein report an unusual case of persistent left superior vena cava terminating in a left atrium with normal coronary sinus, which was revealed at the time of permanent pacemaker implantation after a second operation for recurrent left atrioventricular valve regurgitation. Because this anomaly had gone undiagnosed at the first operation, we were unable to diagnose it prior to the second operation, because the preoperative coronary angiogram clearly demonstrated a coronary sinus that was not dilated. We would have repaired the anomaly using a patch or other procedure had it been diagnosed before the second operation in order to prevent cyanosis or brain complications secondary to right-to-left shunting. One should always be on guard for this rare condition.  相似文献   
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