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1.
The amount of polypropylene (PP) extracted by hot solvent extraction increased with increasing naphtha in a naphtha/reformate solvent blend. The stress–strain curves formed the basis for the calculation of several mechanical properties of the residual film. The yield stress, the natural draw ratio, secant modulus, breaking factor, and work expended in drawing were maximum at a 10/90 naphtha/reformate composition. These were explained in terms of extraction of low molecular weight and atactic materials leaving a more stereoregular block, giving maximum properties with the least removal of polymer materials. Further increases in the naphtha component, however, decreased these properties, possibly due to the greater solubilizing effect of naphtha for the PP chains. © 1995 John Wiley & Sons, Inc.  相似文献   
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Primary brain tumors in two dogs were surgically removed followed by postoperative radiation therapy. The two tumors were confirmed histologically to be astrocytoma and meningioma, respectively. After the surgery, the neurological status of each dog improved dramatically and a total dose of 40 Gy was delivered to the surgical site to treat residual tumor tissue. Although the dog with astrocytoma died 6 months after surgery due to unknown causes, the dog with meningioma has lived for over 24 months with a degree of neurological disorder less severe than that before treatment. These results suggested the effectiveness of this type of therapy on brain tumor in dogs and therapeutic modality should be positively planned to treat canine brain tumors.  相似文献   
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Polypropylene (PP) nanocomposites with three different clay loadings were prepared by solution mixing technique. The solution‐mixed nanocomposites were extruded to fibers using a single screw extruder. The PP nanocomposite fibers obtained were uniformly dyed with three distinct disperse dyes at different levels of shade. The enhanced dyeability of PP nanocomposite fibers was characterized by spectrophotometric measurements. Satisfactory wash, light and crock fastness results were also achieved. Mechanical properties and degree of crystallinity of nanocomposite fibers with different clay loadings were also investigated. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007  相似文献   
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Breast reconstruction has been the subject of many controversies. It now seems generally agreed however that the operation has no deleterious influence on the follow up of breast cancer patients and that it has favorable psychologic effects. Breast reconstruction can be performed either by using prostheses or analogous tissues. These two different modalities have each their own advantages and limitations. Deep knowledge of the techniques and their indications allows to select the most appropriate approach in the individual patient and, thus, to improve long term results.  相似文献   
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Despite advances in postnatal care, patients born with a congenital diaphragmatic hernia (CDH) suffer substantial morbidity and mortality. The present study was undertaken to determine the prognostic influence of prenatally-diagnosed liver herniation in the hemithorax in fetuses with CDH. The medical records of 48 patients evaluated for a prenatally-diagnosed left CDH were retrospectively reviewed. Patients were analysed according to the position of the liver by prenatal ultrasound; 32 fetuses had a major portion of the liver herniated into the left hemithorax ('liver up') and 16 had an intra-abdominal liver ('liver down'). Liver position was determined using colour-flow Doppler ultrasonography. There were two fetal deaths in the liver-up group and one in the liver-down group. The liver-up group more frequently required extracorporeal membrane oxygenation (ECMO) support (53 per cent) compared with the liver-down group (19 per cent). Postnatal survival was significantly less in the liver-up group (43 per cent) vs. the liver-down group (93 per cent). Fetuses with congenital diaphragmatic hernia and liver herniated into the hemithorax have a much worse prognosis than similarly afflicted fetuses without liver herniation. Prenatal ultrasonographic diagnosis of congenital diaphragmatic hernia allows for preparation for a critically ill newborn and aids in prenatal family counselling.  相似文献   
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This study investigates the relation between performance on simple tasks dependent on proprioception, and performance of complex perceptual-motor skills in clumsy children and age-matched control children. One hundred and forty-six right-handed children aged between 5 and 8 years were tested on non-visual aiming, non-visual posture matching, the Kinaesthetic Sensitivity Test (KST), and the Movement Assessment Battery for Children (ABC). Half of the children had scores below the 15th centile on the Movement ABC and were classed into the developmental coordination disorder (clumsiness) group. Scores on the proprioceptive tasks were used to predict performance on complex tasks of the subscales of the Movement ABC (manual dexterity, ball skills, and balance). Specific relations were found between the proprioceptive tasks and the subscales of the Movement ABC, but the KST did not predict differences in motor skills, and no relation was found between tasks carried out without vision. Simple non-visual movement tasks do predict performance in more complex skilled tasks but this is affected by many task features rather than simply the reliance on proprioception for information about movement.  相似文献   
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