氟化物吸收与排泄的实验研究

本研究以同一批志愿者为对象,先后观察了人体经皮肤、呼吸道和消化道接触氟化物后的吸收与排泄。结果提示,水中离子型氟化物不能经皮肤吸收;空气中氟靶物(包括气氟与尘氟)经呼吸道的吸收率均值为60.9％,95％可信区间为52.5～69.3％,并且该吸收率与呼吸频率呈负相关;饮水中氟化物经消化道的吸收率接近100％;膳食中氟化物经消化道吸收率均值为91％,95％可信区间为89.7～92.2％。每日总排氟量相当于每日总摄氟量的50％左右。我们认为这一比例与摄氟来源和摄氟量的大小无关。每日尿排氟量占总排氟比例受不同来源氟化物吸收率的影响,本实验条件下为78～91％。每日尿排氟量和每日每公斤体重体内保留氟量均与每日总摄氟量呈正相关,而不依赖于摄氟途径。提示无论经何种途径进入体内的氟化物,其代谢过程可能是一致的。     

Development of an automated closed system for generation of human lymphokine-activated killer (LAK) cells for use in adoptive immunotherapy

Immunotherapy utilizing the adoptive transfer of lymphokine-activated killer (LAK) cells in conjunction with recombinant interleukin-2 (IL-2) can mediate tumor regression in some patients with advanced cancer. The activation of large numbers of LAK cells was performed in roller bottles in a research laboratory setting and required meticulous aseptic technique, at least one skilled technician per patient and one laminar flow hood per patient. To reduce the complexity and expense of LAK cell generation for human immunotherapy trials we have developed a closed-system automated procedure using a continuous flow blood cell separator. PBL were obtained by standard apheresis techniques. Platelets and plasma were elutriated using countercentrifugal flow of saline in the cell separator machine. The washed PBL were underlaid with Ficoll-Hypaque (FH) in the original separation bag. Lymphocytes were then flushed into a collection bag where they were concentrated and washed with 2 liters of saline. Mean recovery from the automated FH technique was 54.6 +/- 4.3% compared to 62.3 +/- 4.0% using manual methods in 50 ml tubes (P greater than 0.05). Cells were diluted in the collection bag with RPMI 1640 +/- 2% human AB serum and could be dispensed in an automated fashion to polyolefin bags via a sample port with 1000-1500 U/ml IL-2. After 3-4 days of culture in 5% CO2 at 37 degrees C, activated cells from the bags were harvested and washed in a closed system using the continuous flow cell separator. Cell yield from the harvest was 79.2 +/- 5.4% in the automated system compared to 64.9 +/- 5.0% in the standard procedure using manual harvest of roller bottles (P less than 0.01). Lytic capacity of the cells against fresh human tumor in a 4 h 51Cr release assay was equivalent in cells processed either by the automated or the conventional manual method. The advantages of a closed system include decreased potential for microbial contamination and reduced labor and capital equipment costs. This technique may be easily adapted for use with other cell collection and culture systems.     

Nursing education and professional role acquisition. A longitudinal study of expectations and attitudes towards nurse role acquisition

This article deals with professional role acquisition in nurses and discusses results from three studies concerning expectations and attitudes towards this acquisition. The studies have been carried out in Sweden. The discussion comprises expressed expectations and attitudes of nurse students and registered nurses in relation to our theoretical perspectives presented in a former article. The theoretical perspectives concentrate on three aspects of social action: change-drama, interchange-ritual, and maintenance-routine. The results indicate that the professional nurse role is acquired according to a traditional pattern, in spite of changes in curriculum and goals of nursing education and health care. Changes made to develop and improve the conditions under which role acquisitions take place.