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991.
Twenty-three electromagnetic flow transducers with lumen diameters of 3.5-6.0 mm were implanted in rhesus monkeys and baboonss for 12 h to 120 days. Each flow transducer was calibrated 1) in vitro on dialysis tubing with saline before implantation, 2) in vivo the last day of the implant period, and 3) again in vitro after the flow transducer was recovered. Three other flow transducers were implanted on femoral arteries of baboon just central to an arteriovenous Silastic shunt, and were calibrated in vivo daily for 23-47 days. In vitro sensitivity was not affected by implant durations of up to 120 days. In vivo sensitivity fluctuated unpredictably for the first 3-4 wk of implant, after which it followed a systematic course that depended on the lumen size. In vivo sensitivity at any time during implant (after the initial period) could be accurately predicted by knowing either the in vitro sensitivity or the terminal in vivo sensitivity.  相似文献   
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A patient with atypical Ph negative chronic myeloid leukaemia presented with the sudden onset of profound deafness. He survived only eight months. Detailed histological investigation performed at necropsy showed loss of ganglion cells and afferent nerve fibres in the cochlea and vestibule associated with extensive fibrosis and new bone formation in the labyrinthine spaces. Both leucophoresis and high dose chemotherapy capable of rapid cytoreduction are recommended in patients with chronic myeloid leukaemia with profound hearing loss, as conventional chemotherapy is rarely followed by recovery.  相似文献   
997.
Cortisol excretion in high and low cynically hostile men   总被引:4,自引:0,他引:4  
Cynical hostility as measured by the Cook and Medley Hostility (Ho) Scale has been found in some studies to be associated with increased risk of life-threatening illness. Previous laboratory studies of cardiovascular reactivity have been consistent with the general hypothesis that increased physiological responsiveness is one possible mechanism underlying the association between hostility and health. The present study extended this previous research by evaluating urinary cortisol excretion during routine daily activities in a sample of high and low cynically hostile young men. Although high and low Ho groups did not differ in their cortisol excretion upon awakening, the high Ho group displayed more than twice the increase in cortisol excretion during daytime hours as that occurring among low hostile men. This difference dissipated during the evening hours. Results are discussed in terms of possible physiological mechanisms linking hostility and health.  相似文献   
998.
This study reviews the current understanding of the pattern of breast cancer among whites, African Americans, and West Africans who have never immigrated to the US to find better ways of improving the prevention, early detection, and care of breast cancer world-wide. In the United States, the behavior pattern of breast cancer in African-American women differs from that of white women. Among the three populations, breast cancer appears to be least common in nonimmigrant West-African women. The peak incidence in African Americans and West Africans occurs around the premenopausal period while it occurs postmenopausal period in whites. Also, unlike white women, West-African and African-American women present late for treatment with a greater cancer burden and consequently lower survival rates. The predominant histological type is infiltrating ductal carcinoma in the three groups but the highest percentage (33%) of infiltrating poorly differentiated anaplastic carcinoma occurs in West Africans. Menstrual and obstetric history, obesity, and high body mass index status appear to be greater specific risk factors among African Americans than among West Africans. African Americans and West Africans have three "Ls" in common: late stage in seeking treatment, lower age at peak incidence with severe tumor burden, and consequently lower survival rates. There is a need for more detailed population-based research at molecular levels to elucidate the basis for some of these features.  相似文献   
999.
Aims—To determine the extent of clonal cell contamination of peripheral blood progenitor cell (PBPC) collections in patients with multiple myeloma (MM) and to assess the purging efficacy of CD34 positive selection.  相似文献   
1000.
Previous research during the development of Antibody IDentification Assistant (AIDA) revealed that many medical technology students and other laboratory personnel have serious difficulties in determining the specificity of blood group alloantibodies, especially weak or multiple antibodies. Based on these previous results, AIDA was modified to provide a teaching environment for medical technology students. We report the results of a rigorous, objective evaluation of the resultant system, the Transfusion Medicine Tutor (TMT). The results show that the students who were taught by an instructor using TMT to provide the instructional environment went from 0 percent correct on a pretest case to 87 percent correct on posttests (n = 15). This increase compares with an improvement rate of 20 percent by a control group (n = 15) who used a passive version of the system with the tutoring functions turned off.  相似文献   
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