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31.
Die Unfallchirurgie - 相似文献
32.
33.
Serum, plasma, and postmortem blood treated with two volumes of N,N-dimethylformamide (DMF) and centrifuged, were directly analyzable by means of the EMIT d.a.u. reagents on the Syva Autocarousel in the same manner as urine. Cutoff values in milligrams (immunochemically cross-reactive analyte equivalents)/L are 0.05 for morphine (MOR), 0.15 for benzoylecgonine (BZE), 0.20 for oxazepam (OX), and 0.02 for 11-nor-delta 9-tetrahydrocannabinol carboxylic acid (THCC). The relationship of concentrations (micrograms/mL serum) to absorbance changes (delta A) were S-shaped up to greater than 3.0 for MOR, 4.0 for BZE, greater than 5.0 for OX, and 0.2 for THCC. Beyond these maximal concentrations, delta A values declined. Thus, negatives should be repeated on substantially diluted aliquots to avoid missing extraordinarily high positives. "False" quantitative negative/positive noncongruence between total EMIT cross-reactives and free-drug analyses by gas chromatography/mass spectrometry (GC/MS) were 0/17 (N = 75) for opiates, 8/0 (N = 119) for cocaine products, and 19/5 (N = 103) for cannabinoids. For benzodiazepines (N = 58) the "false" negative/"false" positive ratio of EMIT (total)/high performance liquid chromatography (HPLC) (free) was 4/4. Within-day precision as coefficient of variation (CV) of quantitative estimates was 8-18%. For between-day precision, quantitative estimates varied by 8% for MOR, 15% for BZE, 18% for OX, and 34% for THCC. 相似文献
34.
Hormonal fluctuations associated with the menstrual cycle influence
appetite control and eating behaviour. Energy intake varies during the
reproductive cycle in humans and animals, with a periovulatory nadir and a
luteal phase peak. Patterns of macronutrient selection show less
consistency but a number of studies report carbohydrate cravings in the
premenstrual phase, particularly in women with premenstrual syndrome. The
cyclical nature of food cravings are frequently, but not invariably,
associated with depression. Fluctuations in appetite, cravings and energy
intake during the menstrual cycle may occur in parallel with cyclical
rhythms in serotonin, which can be accompanied by affective symptoms. The
premenstrual phase can be considered as a time when women are especially
vulnerable to overconsumption, food craving and depression; this is often
associated with low serotonin activity.
相似文献
35.
36.
Elliott DE Setiawan T Metwali A Blum A Urban JF Weinstock JV 《European journal of immunology》2004,34(10):2690-2698
Inflammatory bowel disease (IBD) is prevalent in industrialized countries, but rare in less-developed countries. Helminths, common in less-developed countries, may induce immunoregulatory circuits protective against IBD. IL-10(-/-) mice given piroxicam develop severe and persistent colitis. Lamina propria mononuclear cells from colitic IL-10(-/-) mice released IFN-gamma and IL-12. The ongoing piroxicam-induced colitis could be partially blocked with anti-IL-12 monoclonal antibody suggesting that the inflammation was at least partly IL-12 dependent. Colonization of piroxicam-treated colitic IL-10(-/-) mice with Heligmosomoides polygyrus (an intestinal helminth) suppressed established inflammation and inhibited mucosal IL-12 and IFN-gamma production. H. polygyrus augmented mucosal IL-13, but not IL-4 or IL-5 production. Transfer of mesenteric lymph node (MLN) T cells from IL-10(-/-) animals harboring H. polygyrus into colitic IL-10(-/-) recipients inhibited colitis. MLN T cells from worm-free mice did not. Foxp3 (scurfin) drives regulatory T cell function. H. polygyrus enhanced Foxp3 mRNA expression in MLN T cells that had regulatory activity. This suggests that H. polygyrus inhibits ongoing IL-10(-/-) colitis in part through blocking mucosal Th1 cytokine production. Resolution of inflammation is associated with increased IL-13 production and can be adoptively transferred by MLN T cells. 相似文献
37.
Telfer JF; Thomson AJ; Cameron IT; Greer IA; Norman JE 《Human reproduction (Oxford, England)》1997,12(10):2306-2312
Superoxide, an agent which attenuates the half-life of nitric oxide, is
metabolized and synthesized by superoxide dismutase (SOD) and xanthine
oxidase, respectively. Over the last few years much work has focused on the
role of nitric oxide in human parturition. The aim of this study was to
determine whether the onset of human parturition is associated with a
change in the expression of copper/zinc superoxide dismutase (Cu/Zn SOD),
manganese superoxide dismutase (Mn SOD) or xanthine oxidase within the
uterus. Samples of myometrium, placenta, decidua and fetal membranes were
obtained from women before and after the onset of labour at term.
Immunocytochemistry was used to localize Cu/Zn SOD, Mn SOD and xanthine
oxidase and measure SOD enzyme activity. Cu/Zn and Mn SOD-like
immunoreactivity was detected in syncytiotrophoblast cells, villous stromal
cells and endothelial cells of blood vessels in the placenta. In the
myometrium Cu/Zn and Mn SOD were localized to myocytes and endothelial
cells and to some vascular smooth muscle cells. In the fetal membranes we
observed staining for Cu/Zn SOD and Mn SOD in the amnion, chorion,
extravillous trophoblast and decidua. There was no difference in SOD enzyme
activity or staining intensity for SOD between different cell types before
and during labour. Xanthine oxidase immunoreactivity was identified in each
of the tissues examined and again there was no difference in immunostaining
in tissues obtained from women delivered before or after the onset of
labour. These results show that the pregnant uterus is capable of both
synthesizing and degrading superoxide and suggest that superoxide dismutase
and xanthine oxidase may play a role in the maintenance of uterine
quiescence during pregnancy, but not in the initiation of parturition.
相似文献
38.
Derrick Walker Janine Jason Kelly Wallace Justin Slaughter Virginia Whatley Alison Han Okey C. Nwanyanwu Peter N. Kazembe Hamish Dobbie Lennox Archibald William R. Jarvis 《Clinical and Vaccine Immunology : CVI》2002,9(5):1049-1056
Cytokines regulate cellular immune activity and are produced by a variety of cells, especially lymphocytes, monocytes, and macrophages. Multiparameter flow cytometry is often used to examine cell-specific cytokine production after in vitro phorbol 12-myristate 13-acetate and ionomycin induction, with brefeldin A or other agents added to inhibit protein secretion. Spontaneous ex vivo production reportedly rarely occurs. We examined the spontaneous production of interleukin 2 (IL-2), IL-4, IL-6, IL-8, IL-10, tumor necrosis factor alpha (TNF-α), and gamma interferon (IFN-γ) by peripheral-blood B lymphocytes, T cells, CD8− T cells, CD8+ T cells, CD3− CD16/56+ lymphocytes (natural killer [NK] cells), CD3+ CD16/56+ lymphocytes (natural T [NT] cells), and/or monocytes of 316 acutely ill hospitalized persons and 62 healthy adults in Malawi, Africa. We also evaluated the relationship between spontaneous and induced cytokine production. In patients, spontaneous TNF-α production occurred most frequently, followed in descending order by IFN-γ, IL-8, IL-4, IL-10, IL-6, and IL-2. Various cells of 60 patients spontaneously produced TNF-α; for 12 of these patients, TNF-α was the only cytokine produced spontaneously. Spontaneous cytokine production was most frequent in the immunoregulatory cells, NK and NT. For IL-2, IL-4, IL-6, IL-8, and IL-10, spontaneous cytokine production was associated with greater induced production. For TNF-α and IFN-γ, the relationships varied by cell type. For healthy adults, IL-6 was the cytokine most often produced spontaneously. Spontaneous cytokine production was not unusual in these acutely ill and healthy persons living in an area where human immunodeficiency virus, mycobacterial, malaria, and assorted parasitic infections are endemic. In such populations, spontaneous, as well as induced, cell-specific cytokine production should be measured and evaluated in relation to various disease states. 相似文献
39.
Oral administration of antigens from intestinal flora anaerobic bacteria reduces the severity of experimental acute colitis in BALB/c mice 总被引:5,自引:0,他引:5
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Verdù EF Bercik P Cukrowska B Farre-Castany MA Bouzourene H Saraga E Blum AL Corthésy-Theulaz I Tlaskalova-Hogenova H Michetti P 《Clinical and experimental immunology》2000,120(1):46-50
Homeostasis between indigenous intestinal flora and host response may be broken in inflammatory bowel disease. The present study explores whether repeated oral administration of intestinal flora antigens can protect mice against dextran sodium sulphate (DSS)-induced colitis. Sonicates of Gram-positive, Gram-negative, or anaerobic resident bacteria isolated from mouse intestinal flora were fed to BALB/c mice by gastric gavage, with or without cholera toxin. After four weekly doses of 1 mg of these antigen preparations (or of PBS as control), DSS colitis was induced. One week later colitis was evaluated by clinical scores and histology. Mice fed a pool of the three sonicates had decreased inflammation scores (5 (1-14); median (range)) compared with PBS-fed control animals (15 (7-19); P < 0.05). Decreased inflammation was observed in mice fed anaerobic bacteria antigens (7 (6-11); P < 0.05 versus control), but not in mice fed a pool of Gram-positive and -negative sonicates (16 (12-16)). Inflammation scores of mice fed antigens with cholera toxin were similar to those of PBS-fed control animals. DSS-induced colitis can be suppressed by oral administration of normal intestinal flora antigens containing anaerobes. 相似文献
40.
Evaluation of cell mediated immune responses in untreated cases of leprosy 总被引:3,自引:8,他引:3
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G P Talwar A D Krishnan V L Mehra E A Blum J M Pearson 《Clinical and experimental immunology》1972,12(2):195-203
Twenty-three leprosy patients have been studied in an endemic area before institution of chemotherapy. These were comprised of ten lepromatous leprosy, four borderline lepromatous and nine tuberculoid leprosy cases on basis of clinical features, bacteriological and marphological indices. Histopathology of skin biopsies classified two as truly polar lepromatous leprosy (LL) and three as polar tuberculoid (TT), while the remaining eighteen were at various stages of evolution towards lepromatous or tuberculoid end of the spectrum. All lepromatous and borderline leprosy patients showed negative delayed hypersensitivity reaction with lepromin, but six out of fourteen patients in this category gave positive reaction with PPD. Blast transformation with PHA of peripheral leucocytes from all cases of lepromatous leprosy cultured in standard AB serum was depressed in comparison with cells from normal controls. 3H-thymidine incorporation in DNA of leucocytes in presence of leprolin was lower in cells of lepromatous leprosy group as compared to those from tuberculoid and borderline cases. There was lack of production of macrophage aggregation factor in all except one case of lepromatous leprosy while the test for this factor was positive for most of the tuberculoid leprosy patients. The homing characteristics of lymphocytes tagged with 51Chromium into liver and spleen of test mice were altered from the normal pattern in a large number of leprosy cases. 相似文献