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31.
B J Hart J Wilting J J de Gier 《Methods and findings in experimental and clinical pharmacology》1987,9(2):127-131
The relation between free serum and saliva concentrations of nitrazepam in healthy male volunteers has been studied. It was found that the average value of free serum concentrations from all volunteers was twice the average value of corresponding saliva concentrations. Sometimes mean values of serum, free serum and saliva concentrations are used in correlation studies. However, the data from individual volunteers showed that there was no correlation between them. Statistics can easily introduce false pictures for correlations between free serum and saliva concentrations of nitrazepam, whereas no correlation could be found on the basis of results from individuals. In response studies such as the effects of drugs on driving performance, the free serum and saliva concentrations of a drug from individual volunteers should therefore be considered. This will complicate the use of saliva in epidemiological studies on drugs and driving. 相似文献
32.
Stimulation or inhibition of the respiratory burst in cultured macrophages in a mycobacterium model: initial stimulation is followed by inhibition after phagocytosis. 总被引:4,自引:4,他引:0 下载免费PDF全文
Microorganisms cause varying degrees of stimulation of superoxide (O2-) production (respiratory burst [RB]) in macrophages but in some cases apparently inhibit the RB induced in the same monolayers by a conventional stimulator. We have explored these differences. A mycobacterium model, the slowly multiplying mouse pathogen Mycobacterium microti, induced a modest RB in resident macrophage monolayers, compared with the substantial RB induced by opsonized zymosan (Zy). However, if the 1-h M. microti pulse immediately preceded the Zy assay (instead of being concurrent), the RB was consistently less than that elicited by the Zy alone. Cytochalasin (an inhibitor of phagocytosis) enhanced Zy-induced RB, supporting the view that the burst is cell surface mediated, but this agent apparently eliminated the inhibition of the Zy-induced RB caused by prior M. microti exposure, suggesting that this inhibition may have an intracellular origin. The inhibition described extended not only to another mycobacterium (Mycobacterium bovis BCG) but also to a previous application of Zy itself. The general implications for macrophage functions of these observations on timing and sites of initiation are briefly discussed. 相似文献
33.
郭永建 《福建医科大学学报》1994,(1)
采用间接ELISA检测23名肾移植受者血清巨细胞病毒(CMV)抗体,共检出18名(78%)活动性CMV感染,其中10名(44%)为原发性感染。结果证实CMV-IgE和-IgA具有较好的血清学诊断价值,优于CMV-IgM。 相似文献
34.
Anticoagulant effects of sulphonated polyurethanes. 总被引:1,自引:0,他引:1
J H Silver A P Hart E C Williams S L Cooper S Charef D Labarre M Jozefowicz 《Biomaterials》1992,13(6):339-344
Sulphonated polyurethanes have been shown to have excellent blood contacting properties. In this paper, similar polyurethanes which are water soluble have been investigated to determine their influence on thrombus formation. These polymers were shown to delay clotting times in the following ways: by direct complex formation between the polymer and thrombin; by interference with fibrin polymerization; and by complex interactions between polymer, thrombin, plasma antiproteases and fibrinogen in plasma. 相似文献
35.
Diane Hart 《Plastic surgical nursing》2003,23(2):55-63, 72
Having nice breasts is important to many women and their self-images. For those women who have had congenital deformities, were not blessed naturally with the shape they wanted, have had experiences that have adversely affected breast tissue, or have had a mastectomy as a result of breast cancer, breast implants can provide a boost in self-confidence. This article provides an overview of breast implant issues and treatments, and reviews breast implant complications, their potential causes and treatments. 相似文献
36.
D A Hart 《Haemostasis》1988,18(3):154-162
Mice bearing the B16 melanoma or treated with Corynebacterium parvum develop elevated levels of plasma neutral proteinase activity. Similar experiments carried out with C57BL/6-bg/bg (beige) mice, which are genetically deficient in polymorphonuclear neutrophil (PMN) proteinases, revealed that such mice develop significantly diminished elevation in plasma proteinase activity compared to C57BL/6-bg/+ mice. Lysates of C. parvum elicited PMN from beige mice contained approximately 80% less neutral proteinase activity as did lysates of PMN from bg/+ mice. These results indicate that host cells, such as PMN, may become activated during the tumor progression, or following C. parvum treatment, causing degranulation and a subsequent elevation in plasma proteinase levels. If such an interpretation is correct, then this phenomenon may be the murine corollary to what has been observed in patients with certain inflammatory diseases or tumors. 相似文献
37.
Peter F. Bruning Jaap Van Doorn Johannes M. G. Bonfrr Paul A. M. Van Noord Catharina M. Korse Theodora C. Linders Augustinus A. M. Hart 《International journal of cancer. Journal international du cancer》1995,62(3):266-270
Insulin-like growth factor 1 (IGF-1) is a potent mitogen for human breast-cancer cells in vitro. In circulation, most of IGF-1 is bound to IGF-binding protein 3 (IGFBP-3). This high-affinity binding is thought to have an important limiting effect on the availability of IGF-1 for biological activity. To assess the availability of IGF-1 for receptor binding, we determined serum levels of IGF-1 and IGFBP-3 and IGF-1/IGFBP-3 ratios. In a case-control study, 150 women aged 38 to 75 years presenting with stage-l or-II breast cancer were investigated just prior to surgery (n = 76), or to irradiation one month after surgery (n = 74). The population-based control group consisted of 441 women of the same age having no breast cancer. Women reporting diabetes mellitus or other hormonal abnormalities were excluded. Premenopausal cases showed elevated IGF-1 serum concentrations, decreased IGFBP-3 levels and increased IGF-1/IGFBP-3 ratios. The IGF-1/IGFBP-3 ratio was a significant breast-cancer risk factor, also after adjustment for age, family history, height, body-mass index, body-fat distribution, and serum levels of C-peptide. The relative risk was 7.34 for the highest compared with the lowest quintile of IGF-1/IGFBP-3. The presence or absence of tumor had no influence on these results. Increased levels of available IGF-1 in the circulation of pre-menopausal women may contribute to the development of breast cancer. © 1995 Wiley-Liss Inc. 相似文献
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