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991.
AK Sood JI Sorosky N Mayr S Krogman B Anderson RE Buller DH Hussey 《Canadian Metallurgical Quarterly》1997,80(6):1073-1078
BACKGROUND: Data regarding radiation therapy for pregnant patients with cervical carcinoma are limited. The goal of this study was to assess the effects of pregnancy on tumor control, survival, and morbidity associated with radiation therapy administered to pregnant patients. METHODS: The authors performed a retrospective case-control analysis of 26 women with cervical carcinoma who were diagnosed during pregnancy and treated primarily with radiation therapy. These cases were matched with 26 controls based on age, histology, stage, treatment, and year of treatment. RESULTS: Patients were treated with external beam radiation (mean dose, 46.7 gray [Gy]) and intracavitary radiation (mean dose, 56.5 Gy to Point A). Two patients with Stage IA2 squamous cell carcinoma treated in the third trimester had a planned delay in treatment of 3 weeks, and both infants had an uncomplicated neonatal course. Seven pregnant patients (2 Stage IB1, 5 Stage IB2) underwent radiation after radical hysterectomy was aborted due to positive regional lymph nodes. Three patients diagnosed during the first trimester were treated with radiation with the fetus in situ, and all had spontaneous abortions 20-24 days after the start of radiation (mean dose, 34 Gy). In all these cases, radiation was interrupted for only 3 days or less. There were no statistically significant differences in recurrence rates or survival between the pregnant group and the controls. Short term toxicity was comparable in pregnant and nonpregnant patients and easily controlled. Long term complications were more common in controls (12% in pregnant patients, 27% in controls), but this difference was not statistically significant. Most complications were likely related to radiation techniques (particularly the predominance of cobalt-60). CONCLUSIONS: Planned delay in treatment should be offered to pregnant patients with early stage squamous cell carcinoma in the late second and early third trimester. Patients diagnosed in the first or second trimester who are not good candidates for planned delay in treatment should be given radiation therapy immediately. It may be necessary to reconsider planned radical hysterectomy for pregnant women with Stage IB2 disease due to the high rate of lymph node positivity found on exploration. For patients with advanced disease, radiation therapy appears to be a safe and effective modality. 相似文献
992.
S Stark AK Petridis SJ Ghim AB Jenson JN Bouwes Bavinck G Gross E Stockfleth PG Fuchs H Pfister 《Canadian Metallurgical Quarterly》1998,111(4):696-701
The dietary intake of saturated fatty acids affects arteriosclerosis. We studied the effect of supplementation (15% wt/wt) of a hyperlipemic diet (1.3% cholesterol) with evening primrose oil (Oenothera biennis) in four groups of 10 rabbits each. After 6 weeks the aortic endothelium was analyzed morphologically with scanning electron microscopy, and the arterial wall was studied with morphometric techniques and cell nucleus counts. Endothelial functioning was analyzed by measuring prostacyclin synthesis, and thrombogenicity of the subendothelium was studied by perfusion in a Baumgartner annular chamber. Evening primrose oil reduced hypercholesterolemia (from 29 +/- 3 to 12 +/- 2 nmol/l), increased HDL-cholesterol (from 0.5 +/- 0.06 to 0.8 +/- 0.09 nmol/l) and doubled prostacyclin synthesis (from 2.7 +/- 2 to 6.2 +/- 0.7 ng/mg aorta) in rabbits on the hyperlipemic diet, reduced subendothelial surface occupied by platelets (from 6.9 +/- 0.4 to 4.8 +/- 0.3%), and reduced human platelet adhesion on the subendothelium (from 53.3 +/- 6% to 38 +/- 8%, respect to total occupation). Morphological analyses showed that evening primrose oil diminished endothelial lesions caused by the atherogenic diet, reducing area of the arterial wall (from 6.9 +/- 0.2 to 4.7 +/- 0.2 microm2 x 10(6)) and the degree of neointimal proliferation (from 0.6 +/- 0.02 to 0.4 +/- 0.09 microm2 x 10(6)). We conclude that in our experimental model, this dietary supplement enhanced the antithrombotic capacity of the endothelium, reduced subendothelial thrombogenicity, and diminished the extent of vascular wall lesions caused by the hyperlipemic diet. 相似文献
993.
In this work, the stress analysis of isotropic and ortotropic laminae both with a hole and without a hole and laminated both with a hole and without a hole composite plates have been examined using the finite element method. In order to solve the problem, a computer program has been written by using characteristics of eight-node isoparametric plane element. The calculations have been tested on various composite and steel materials by this program. The results have been shown in diagrams and tables and compared with literature. It was observed that the stress distributions in the plate with a hole was totally different from the plate without a hole. The analyses have showed that, the elastic stresses have been gradually reduced as moving from the first layer to the second. 相似文献
994.
995.
996.
997.
FP Tolentino-Silva AK Russo SL Cravo OU Lopes 《Canadian Metallurgical Quarterly》1998,31(10):1339-1343
Several studies demonstrate that, within the ventral medullary surface (VMS), excitatory amino acids are necessary components of the neural circuits involved in the tonic and reflex control of respiration and circulation. In the present study we investigated the cardiorespiratory effects of unilateral microinjections of the broad spectrum glutamate antagonist kynurenic acid (2 nmol/200 nl) along the VMS of urethane-anesthetized rats. Within the VMS only one region was responsive to this drug. This area includes most of the intermediate respiratory area, partially overlapping the rostral ventrolateral medulla (IA/RVL). When microinjected into the IA/RVL, kynurenic acid produced a respiratory depression, without changes in mean arterial pressure or heart rate. The respiratory depression observed was characterized by a decrease in ventilation, tidal volume and mean inspiratory flow and an increase in respiratory frequency. Therefore, the observed respiratory depression was entirely due to a reduction in the inspiratory drive. Microinjections of vehicle (200 nl of saline) into this area produced no significant changes in breathing pattern, blood pressure or heart rate. Respiratory depression in response to the blockade of glutamatergic receptors inside the rostral VMS suggests that neurons at this site have an endogenous glutamatergic input controlling the respiratory cycle duration and the inspiratory drive transmission. 相似文献
998.
999.
AK Ghosh K Krishnan DE Walters W Cho H Cho Y Koo J Trevino L Holland J Buthod 《Canadian Metallurgical Quarterly》1998,8(8):979-982
A series of novel spirocyclic ethers were designed to function as nonpeptidal P2-ligands for HIV-1 protease inhibitors. Incorporation of designed ligands in the (R)-(hydroxyethylamino)sulfonamide isostere afforded potent HIV protease inhibitors. 相似文献
1000.
M Cirit M Ozkahya CS Cinar E Ok S Aydin F Ak?i?ek EJ Dorhout Mees 《Canadian Metallurgical Quarterly》1998,13(2):389-392
We recovered an unusual bacterial strain from blood or sputum of three patients with septicemia, endocarditis, and/or respiratory failure. The three isolates were thin, curved, gram-negative, light brown, pigment-producing bacilli with variable catalase activity. They were asaccharolytic, oxidase-negative, nonmotile, and fastidious. Identification was not possible on the basis of these characteristics alone or in combination with cellular fatty acid profiles. Nucleic acid amplification and sequence analysis of the 16S rRNA gene revealed that all three isolates were identical and most closely related to the emerging pathogen Bordetella holmesii, diverging from the published sequence at three nucleotide positions (99.8% similarity). Isolation of a B. holmesii-like pathogen from sputum suggests that, in addition to producing septicemia, the organism may inhabit the respiratory tract like other Bordetella species. 相似文献