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71.
72.
A case of a 54 year old female with cor tritriatum is described. Diagnostic role of transthoracic and transesophageal echocardiography is discussed.  相似文献   
73.
74.
The twin-reversed arterial perfusion (TRAP) sequence and development of an acardius are rare and severe complications in monozygotic twin pregnancy. Haemodynamic disturbances in placental perfusion via abnormal vascular anastomoses allow inter-twin transfusion to occur. Because of blood perfusion, one of the twins is poorly oxygenated and contains metabolic waste products. Retrograde placental perfusion leads to the formation of a non-viable malformed acardiac foetus. We studied the effects of haemodynamic disturbances in acardiac foetus on the development of the nervous system. The acardius was a product of a 32-weeks pregnancy. Caesarean section yielded a skin covered ovoid mass (size, 10 x 8 cm; weight, 220 g). The dissection of the acardiac twin showed a skin with hair and appendages, rudimentary lower limbs, vertebral column and brain mass. The rudimentary brain tissue was considerably disorganised structurally. We distinguished two main morphological forms of various appearances. In the centre, we observed a scarcely vascularised mass of tissue containing mature and immature neurones, glial cells and randomly distributed fibres. The mass of tissue appeared poorly differentiated, although there were some arrangements reminiscent of cerebral structures. Clusters of neurones provided a slight suggestion of nuclear or fibre structure. The cerebellar cortex was the only well recognisable structure. In the other fragment of the tissue, we found a slit cavity with ependymal outline and well-developed choroid plexus, which seemed to represent the 3rd ventricle. The scarcely vascularised disorganised tissue was surrounded by the highly vascularised one. It included many thin-walled sinusoid vessels. In some places, they were so concentrated that they resembled cavernous haemangioma. The spinal cord appeared comparatively well organised with a slightly dilated central canal. The morphological picture of the rudimentary brain tissue was similar to the picture of the cerebrovasculosa area. The effect of ischaemia in the presented case is the anomalous formation of the cerebral structures. The morphological features imply that the failure occurred after neurulation and before the prosencephalic began to grow. The failure of neural tube formation occurred on the 22nd-25th day of gestation. The malformed formation of the nervous system might be caused by impaired induction due to altered gene expression or to the interference of exogenous agents that interrupt normal development. The haemodynamic abnormal placental circulation, which induced lack of oxygen supply and nutritional deficiency, implies the morphological pattern of the anomaly.  相似文献   
75.
Male breast cancer constitutes less than 1% of all breast cancer cases. Special types, such as Paget disease of the breast, are extremely rare. To our knowledge there are less than 50 cases of Paget disease of male breast described in world medical literature. Authors present pathologically proven but clinically silent case of Paget disease of the nipple in an 86-year old male with breast cancer. Literature data suggest that the prognosis of male Paget cancer is worse than in "ordinary" male breast cancer. Therefore, the histologic diagnosis of Paget disease, even in an asymptomatic male patient, may have negative prognostic value.  相似文献   
76.
OBJECTIVES—To investigate possible relations between respiratory health and past airborne exposure to refractory ceramic fibres (RCFs) and respirable dust in workers at six European factories, studied previously in 1987.
METHODS—The target population comprised all current workers associated with RCF production, plus others who had participated in 1987 "leavers". Information was collected on personal characteristics, chest radiographs, lung function, respiratory symptoms, smoking, and full occupational history. Regression analysis was used to study relations between indices of health of individual workers and of cumulative exposure to airborne dust and fibres, and likely past exposure to asbestos.
RESULTS AND DISCUSSION—774 workers participated (90% of current workers, 37% of leavers). Profusion of small opacities in exposed workers (51% 0/1+; 8% 1/0+) was similar to that among an unexposed control group but higher than in new readings of the 1987 study films (11% 0/1+, 2% 1/0+). The large difference between 1987 and recent films may be, at least in part, a reading artefact associated with film appearance. Small opacities of International Labour Organisation (ILO) category 1/0+ were not associated with exposure. An association of borderline significance overall between 0/1+ opacities and exposure to respirable fibres was found for some exposure periods only, the time related pattern being biologically implausible. Pleural changes were related to age and exposure to asbestos, and findings were consistent with an effect of time since first exposure to RCFs. Among men, forced expired volume in 1 second (FEV1) and forced vital capacity (FVC) were inversely related to exposure to fibres, in current smokers only. FEV1/ FVC ratio and transfer factor (TLCO) were not related to exposures. The estimated restrictive effect was on average mild. Prevalence of respiratory symptoms was low. Chronic bronchitis and its associated symptoms (cough, phlegm) showed some association with recent exposure to respirable fibres. This could be due to an irritant effect of RCFs.


Keywords: respiratory health; ceramic fibres  相似文献   
77.
Excel97在药物分析中的应用   总被引:1,自引:0,他引:1  
目的:在药物分析中,电子表格软件MicrosoftExce197for Windows。方法:利用Excel的数据处理功能,进行药物的图表绘制、数据计算和统计处理,回归分析,特别是计算分析,并可建立分析数据库。结果和结论:Excel操作简单,功能强大,数据分析工作直观。  相似文献   
78.
目的:比较国产辛伐他汀与进口辛伐他汀治疗原发性高胆固醇血症的疗效及安全性。方法:采用开放区组随机对照、多中心的临床设计。150例高胆 固醇血症病人分为验证组(50例)、对照组(48例)和开放组(52例),剂量均为每晚顿服10mg,服药8周。结果:验证组与对照组服药前后比较,血清总胆 固醇(TC)分别降低26.36%和28.3%,低密度脂蛋白胆固醇(LDL-C)分别降低33.17%和35.51%;验  相似文献   
79.
Diet and cancer prevention: the fiber first diet   总被引:3,自引:0,他引:3  
Diet can play a major role in cancer prevention. The international differences in cancer incidence are largely accounted for by lifestyle practices that include nutrition, exercise, and alcohol and tobacco use. About 50% of cancer incidence and 35% of cancer mortality in the U.S., represented by cancers of the breast, prostate, pancreas, ovary, endometrium, and colon, are associated with Western dietary habits. Cancer of the stomach, currently a major disease in the Far East, relates to distinct, specific nutritional elements such as excessive salt intake. For these cancers, information is available on possible initiating genotoxic factors, promoting elements, and prophylactic agents. In general, the typical diet in the United States contains low levels of the potent carcinogenic agents, heterocyclic amines, formed during the cooking of meats. It provides only about half the potent appropriate fiber intake and is high in calories. About twice as many calories as would be desirable come from fat, certain kinds of which enhance the development of cancers. Other foods with functional properties, such as soy products and tea, can be beneficial. To achieve reduction in risk of certain cancers, diet must be optimized, primarily to reduce caloric intake and the fat component. The latter should be 20% or less of total caloric intake and fiber should be increased to 25- 35 g per day for adults. One approach to achieving these goals is the Fiber First Diet, a diet designed around adequate fiber intake from grains, especially cereals, vegetables, legumes, and fruits, which thereby reduces both calorie and fat intake. Such dietary improvements will not only reduce cancer and other chronic disease risks, but will contribute to a healthy life to an advanced age. A corollary benefit is a lower cost of medical care.   相似文献   
80.
Park  JH; Choi  BI; Han  MC; Sung  KB; Choo  IW; Kim  CW 《Radiology》1987,163(3):619-623
In the Orient there is a high frequency of residual intrahepatic stones after biliary tract surgery. Percutaneous removal of residual intrahepatic stones was attempted in a group of 74 patients. Stones were exclusively intrahepatic in 57 patients, whereas 17 patients also had stones in the common bile duct. Biliary strictures were present in 60 cases (81%). A combination of techniques was used, including preshaped angulated catheters, irrigation-suction, balloon dilation of strictures, and crushing of large stones. In 36 cases all stones were removed and in 14 cases most stones were removed, for a success rate of 67.6%. Biliary stricture was the factor most often responsible for failure.  相似文献   
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