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81.
The present study describes cause-specific mortality of asbestos cement workers in the Emilia Romagna region of Italy. The cohort included workers in ten factories, most of which started operating between 1955 and 1965. Asbestos, mainly chrysotile, constituted 10%–20% of the dry component of the mixture. Crocidolite range between 5% and 50% of total asbestos. Asbestos concentrations up to 44 ff/cc were reported prior to 1975, while in recent years they have usually been below 0–1 ff/cc. The cohort included 3341 workers who had at some time been employed in the ten factories under study. Their mortality experience was compared with that of the population resident in Emilia Romagna. Vital status was ascertained at 1989. Seventy-three subjects were lost to followup (2.2%). Mortality from all causes and from all types of cancer was increased in the cohort. Malignant neoplasms of the respiratory tract showed a significant increase (SMR: 134; 90% confidence interval: 101–175; 40 observed) due to lung cancer (SMR: 124; 90% confidence interval: 91–166; 33 observed) and neoplasms of the pleura, mediastinum, and other parts of the respiratory tract (SMR: 602; 90% confidence interval 237–1267; 5 observed). The discrepancy between observed and expected mortality mainly concerned subjects with at least 20 years of employment in the factories. Five more cases of histologically confirmed mesothelioma occurred after the end of follow-up.  相似文献   
82.
52例肺癌患者放疗前肺功能和放疗疗效关系分析   总被引:1,自引:0,他引:1  
为了探讨放疗前肺功能与放疗疗效的关系,作者于1987年1月至1990年12月对52例无急、慢性呼吸衰竭的肺癌患者在放疗前做了肺功能检测和血气分析,结果表明,放疗前肺功能不能反映肿瘤乏氧程度,也不能作为肿瘤对放疗敏感性的指标,只有直接测量肿瘤原发灶内的乏氧程度才能了解肿瘤对放疗的敏感性,预测放疗的疗效。  相似文献   
83.
Ventilation and perfusion SPECT images during tidal breathing were studied in 15 cases of lung cancer using 81mKr gas and 99mTc-microspheres. Furthermore, functional images of V/Q ratio and Q/V ratio were prepared, and their clinical significance is descussed with reference to general lung function. There was a decreas in %VC and %FEV 1.0in 7 of 15 cases, and an increase of AaDo2 in the blood gas analysis in 12 of 15 cases. Both planar and SPECT images showed ventilation and perfusion abnormalities in all 15 cases. Of these, 12 patients showed matched ventilation and perfusion defects, 2 patients a dead-space effect and 1 patient a shunt effect. In comparing planar and SPECT images, depiction of ventilation and perfusion impairments were equally clear in 11 cases, but in 3, showing a lobar or segmental defect with a shunt effect, the SPECT images were superior. In a patient with markedly impaired function of the affected lung, the remaining function could not be depicted by SPECT. From the above, it seems that better information can be obtained for understanding the ventilation and perfusion states of lung cancer by adding the SPECT images to the planar image.  相似文献   
84.
防晒制剂皮肤安全性的实验研究   总被引:2,自引:0,他引:2  
目的 :探讨同一系列不同SPF(sunprotectionfactor)防晒制剂对皮肤的安全性 ,筛选安全有效的防晒制剂配方。方法 :选用白化豚鼠背部去毛 ,分别涂抹SPF值为 15、2 8、30 +三种防晒制剂 ,以UV光源照射 ,波长为 32 0~4 0 0nm ,强度为 ( 16 8± 2 )mW/cm2 。结果 :三种不同SPF防晒制品对实验动物皮肤各时相点反应积分为 ,SPF15组为0 ;SPF2 8组为 1;SPF30 +组为 3。结论 :三种不同SPF值产品对皮肤的光毒性有一定差异 ,提示SPF值在 2 8以内的防晒制剂皮肤安全性较好 ,SPF30 +的防晒制剂对皮肤有一定光毒刺激反应。  相似文献   
85.
目的 观察犬热缺血供体同种异体肺移植术后早期移植肺功能情况。方法 采用室温下热缺血 3 0min、LPD液灌注后 4℃保存 2 5h时的供肺 ,行右肺同种异体移植手术 7例 ,术前及监测恢复灌注 0 5 ,1,2及 4h的动脉血氧分压 (PaO2 )、肺动态顺应性 (Cdyn)、平均肺动脉压 (mPAP)、肺毛细血管楔压 (PCWP)和心输出量的变化 (CO)。结果 所有受体犬在观察期间均存活。恢复灌注 4h内的肺功能各指标变化差异无显著性 (P >0 0 5 ) ,或者虽然有统计学差异 ,但仍有较好的绝对水平。结论 热缺血 3 0min低温保存 2 5h的供肺可以维持生命 ,恢复灌注后 ,受缺血再灌注损伤的影响 ,在灌注后一段时间内 ,供肺功能下降 ,但仍可较好支持生命。  相似文献   
86.
Objective: Based on the findings that erythropoietin (EPO) has been proved to be a multiple functional cytokine to attenuate ischemia–reperfusion (I/R) injury in various organs such as brain, heart, and kidney in animals, this experiment was designed to evaluate the effect of pretreatment with recombined human erythropoietin (rhEPO) on I/R-induced lung injury. Methods: Left lungs of rats underwent 90 min of ischemia and then were reperfused for up to 2 h. Animals were randomly divided into three experimental groups as sham group, I/R group, and rhEPO + I/R group (a single dose of rhEPO was injected intraperitoneally 3000 U/kg 24 h prior to operation). Lung injury was evaluated according to semi-quantitive analysis of microscopic changes, tissue polymorphonuclear neutrophils (PMNs) accumulation (myeloperoxidase (MPO) activity), and pulmonary microvascular permeability (Evan's blue dying method). Peripheral arterial and venous blood samples were obtained for blood–gas analysis after 5 min occlusion of right lung hilus at the end of reperfusion. The serum concentration of tumor necrosis factor (TNF)- was also measured by the method of enzyme-linked immunosorbent assay. Results: Histological injury scoring revealed significantly lessened lung alveolus edema and neutrophils infiltration in the rhEPO pretreated group compared with I/R group (p < 0.05). The rhEPO pretreated animals exhibited markedly decreased lung microvascular permeability (p < 0.05) and myeloperoxidase activity (p < 0.05). Blood–gas analysis demonstrated that the pretreated animals had significantly ameliorated pulmonary oxygenation function (p < 0.05). The serum concentration of tumor necrosis factor- in rhEPO pretreated group was markedly decreased compared with that of I/R group (p < 0.05). Conclusions: Pretreatment with rhEPO appears to attenuate I/R-induced lung injury. This function is partly related with the capacity that rhEPO inhibits the accumulation of polymorphonuclear neutrophils in lung tissue and decreases the systematic expression of tumor necrosis factor-.  相似文献   
87.
Lung cancer mortality rates among United States and Japanese males were compared and related to smoking and dietary data. Mortality rates increased from 1950 to 1985 in both countries, but the absolute values are consistently lower in Japan (38.2 deaths/100,000 in 1985) than in the U.S. (72.2/100,000). The proportion of smokers is higher in Japan than in the U.S. since 1955. Japanese males start smoking considerably later than U.S. males, but smoke a higher quantity of cigarettes per day. Available information on inhalation practices and yield and type of cigarettes smoked showed no differences among the two countries large enough to account for the differences in mortality rates. Further data in this regard should he obtained. Dietary data show that fat consumption (as percentage of calories) is consistently higher in the U.S. than in Japan from 1950 (40% vs. 7.9%) through 1985 (43.5% vs. 24.5%). A linear relationship is observed between lung cancer mortality and fat intake. Our data support the hypothesis that dietary habits may modulate the carcinogenic effects of tobacco smoking.  相似文献   
88.
An in vitro method for obtaining pressure/volume curves from the lungs of small animals is described. The excised lungs were inflated and deflated with saline or air by a motor-driven syringe controlled by a microcomputer. The computer was programmed to display the curves in real time, correcting when necessary for the compressibility of air in the system. Volume compliance (K=dV/dP×1/V) was calculated by differentiating a polynomial fitted to the measured pressure/volume points. Repeatable curves were obtained from mice aged 24h (body weight 1·3±0·14g (SD), residual lung volume 8·43±1·5 μl (SD). A nonlinear decrease in differential compliance (K=dV/dP×1/V) with increasing strain was observed while the ratio Ksaline/Kair increased from 2·5 to 10 over the range of strains investigated (ε=1–5). The relative surface tension (calculated from the difference between the pressures required to inflate the air and saline-filled organs to a given volume) increased exponentially with increasing volume. We conclude that it is now possible to obtain reproducible pressure/volume curves for lungs with a residual volume of less than 10 μl, from animals weighing approximately 1·5 g and, from these curves, estimate airway compliance and surface tension.  相似文献   
89.
The histological distinction between carcinosarcoma and mesothelioma has received little attention. The object of this study was to describe the histology and immunohistochemistry of two carcinosarcomas presenting as pleural tumours. These were compared with 12 carcinosarcomas from sites within the lung, and with the established features of mesothelioma. Histologically and immunohistochemically, these 'pleural' carcinosarcomas are similar to conventional pulmonary carcinosarcomas but accurate recognition is hindered by their gross appearance and biphasic histology which closely mimic mesothelioma. They may exhibit features such as neutral mucin, expression of carcinoembryonic antigen, squamous differentiation, and neuroendocrine differentiation which, when present, are evidence against mesothelioma. These tumours are rare and have passed unnoticed until now.  相似文献   
90.
Analogs of Neuropeptide Y (NPY) were synthesized with conventional Boc/benzyl protective group strategy. Instead of Asn7 in the native scquence, Boc-Lys(Alloc)-OH was incorporated. At the end of the synthesis the Alloc group was selectively removed by palladium-catalyzed hydrostannolysis and biotin coupled to the e-amino group of Lys7. After cleavage and characterization with plasma desorption mass spectrometry the Ne-7-biotinyl-[Lys7]-NPY and the nonbiotinylated analog [Lys7]-NPY were investigated as ligands to the NPY receptor from rat cerebral cortex. Both analogs were found to be high affinity ligands to the NPY receptor and bound with essentially the same affinity as unmodified NPY.  相似文献   
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