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81.
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In order to investigate the levels of the polycyclic aromatic hydrocarbons, mainly benzo[a]pyrene because of its carcinogenicity, 55 samples of smoke flavour and smoked foods were analysed. The samples tested included 11 samples of liquid smoke flavour and 44 samples of smoked foods like bacon, loin, turkey, sausage, ox rib, etc. from different brands. A liquid chromatographic method was developed using a fluorescence detector. Benzo[a]pyrene was found in 73% of the liquid smoke flavour samples analysed. The levels varied from 0.1 to 336.6 micrograms/kg. Three liquid smoke flavour samples showed levels of benzo[a]pyrene above the maximum level recommended by FAO/WHO (10 micrograms/kg). From the total of 44 smoked food samples analysed, benzo(a)pyrene was detected in 23 samples (52%). The levels varied from 0.1 to 5.9 micrograms/kg. Anthracene and fluoranthene, non-carcinogenic polycyclic aromatic hydrocarbons, were found in almost all the samples analysed. Benzo[ghi]perylene, 3,4-benzofluoranthene and 1,2,3,4-dibenzopyrene were not found in any of the 55 samples analysed.  相似文献   
83.
We report a case of metastatic gastrointestinal leiomyosarcoma treated with high-dose combination chemotherapy and autologous peripheral blood stem cell transplantation. After incomplete surgical resection, enteral, peritoneal and hepatic involvement remained. Postoperatively, standard-dose chemotherapy with etoposide, ifosfamide, cisplatin and epirubicine, and high-dose chemotherapy with the same agents (carboplatin replacing cisplatin) was given. Treatment was well tolerated and the patient remains in complete remission at 36+ months. We conclude that high-dose chemotherapy followed by autologous peripheral blood stem cell transplantation may be of use as treatment for inoperable residual disease after resection of the primary lesion in gastrointestinal and other soft tissue sarcomas.  相似文献   
84.
Can daily short-duration hypoxemia (4-8 hours) induce pulmonary hypertension and right ventricular hypertrophy? A clinical model of this type of hypoxemia does exist: isolated nocturnal hypoxemia in patients with obstructive sleep apnea syndrome (OSAS) or chronic obstructive pulmonary disease (COPD). By investigating the pulmonary hemodynamics of these patients, it should be possible to determine whether nocturnal hypoxemia alone can induce pulmonary hypertension. Although nocturnal hypoxemia (in OSAS as well as in COPD) can induce acute episodes of pulmonary hypertension, it would not appear that nocturnal hypoxemia alone would be sufficient to provoke permanent diurnal pulmonary hypertension. This is the conclusion of recent studies concerning diurnal pulmonary hemodynamics in OSAS and COPD patients exhibiting minimal hypoxemia during the day but significant nocturnal desaturation. The therapeutic consequences of these data, particularly in COPD are important: current evidence is insufficient to treat with nocturnal oxygen therapy COPD patients who have minimal diurnal hypoxemia but significant nocturnal desaturation.  相似文献   
85.
Theoretical activity distribution was determined for 56Co obtained from the 56Fe (p, n) reaction. The reaction was induced by an 8.3 MeV proton beam in a thin surface layer of cast-iron. The distribution was then verified experimentally. The standard deviation of the measured points from the theoretical curve was 3.3 μm. For the thickness range between 5 and 35 μm, frequently used in wear studies, a linear approximation was suggested by the experimental results. Standard error of estimate was 0.69 μm for this range. The S.D. of the experimental points from the theoretical curve 3 as 1.14 μm for the same range.The studies were made with a view to their prospective application in the measurements of wear of car engine components.  相似文献   
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This paper reports a novel remotely actuated manipulator for access to prostate tissue under magnetic resonance imaging guidance (APT-MRI) device, designed for use in a standard high-field MRI scanner. The device provides three-dimensional MRI guided needle placement with millimeter accuracy under physician control. Procedures enabled by this device include MRI guided needle biopsy, fiducial marker placements, and therapy delivery. Its compact size allows for use in both standard cylindrical and open configuration MRI scanners. Preliminary in vivo canine experiments and first clinical trials are reported.  相似文献   
89.
The problem of bending a thin plate is solved by the finite element method. Using a differential equation of the plate element equilibrium determines the potential energy by contour values of displacements and their first derivatives. In the equilibrium state they have to be such that the potential energy reaches its minimum. The suggested calculation algorithm enables the use of multiangular elements of arbitrary shape instead of integration in the area of this element in which curvilinear integrals appear along the element contour. Elaborated also is the program for calculation by computer and verified usability of the method for various elements based on the example of the square plate.  相似文献   
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