Author Keywords: Event-related potentials; females; menstrual cycle 相似文献
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71.
B. Algermissen F. Bauer D. Schadendorf J.-D. Kropp B. M. Czarnetzki 《Experimental dermatology》1994,3(6):290-297
Abstract In order to gain insights into the dynamics of mast cell subpopulations in normal and diseased skin, a novel enzyme-histochemical double and triple staining method was employed that allowed the detection of metachromasia (toluidine blue) and the mast cell proteases tryp-tase and chymase within the same cell. Cryostat sections were used of skin biopsies from the following specimens: normal skin (N=4), psoriasis (N=13), atopic eczema (N=7), lichen planus (N=6), interferon α2a injection sites (N=l) of a leukemic infiltrate and corresponding normal skin of the same patient before and after treatment. (i) Equal numbers of tryptase-and chymase-positive mast cells (MCTC) were obtained in all normal and diseased specimens in papillary and reticular dermis, with threefold increases around appendages, (ii) Tryptase-positive mast cells (MCT) were absent in normal skin, but were markedly increased in a disease-specific pattern within the papillary dermis, the inflammatory infiltrate and around appendages, (iii) Marked increases of MCT were also noted at interferon injection sites within the leukemic infiltrate, but not in the normal skin of the same patient. These data suggest that disease-dependent mast cell dynamics involve only MCT in cutaneous inflammation and that MCT numbers are controlled by distinct, disease-specific local tissue factors. 相似文献
72.
H C Wilkes T W Meade S Barzegar A J Foley L O Hughes K A Bauer R D Rosenberg G J Miller 《Thrombosis and haemostasis》1992,67(5):503-506
The effects of gemfibrozil on several indices of haemostatic activity were explored in male patients with coronary heart disease (CHD). Sixty-three of 71 patients completed a crossover study in which gemfibrozil 1,200 mg/day and matching placebo were each taken in randomised order for 2 months in a double-blind manner, separated by a 2-month washout period. Serum cholesterol decreased by an average (95% confidence interval) of 12 (9 to 15)% and non-fasting triglyceride concentration by 43 (34 to 51)% during active treatment. Plasma prothrombin fragment F1 + 2 concentration, a marker of the in vivo rate of generation of thrombin, was 25 (12 to 37)% lower on average while on gemfibrozil than during the placebo phase. Factor VII coagulant activity (VIIc) and antigen concentration, and fibrinopeptide A concentration were not influenced by gemfibrozil in the group overall. However, the VIIc response appeared to be dependent upon the untreated cholesterol level. Hypercholesterolaemic men (cholesterol greater than 6.5 mmol/l) experienced a significant reduction in VIIc averaging 6% of standard during active therapy. Other effects of gemfibrozil were a 5 (2 to 9)% increase in plasma fibrinogen by a gravimetric method, an 11 (8 to 13)% increase in platelet count, and a 6 (2 to 10)% reduction in white cell count. The reduced incidence of CHD following gemfibrozil therapy in hyperlipidaemic patients may arise in part through a reduction in procoagulant activity and thus the risk of an occlusive coronary thrombosis. 相似文献
73.
74.
Z H Marcus B Lunenfeld R Weissenberg L M Lewin 《Gynecologic and obstetric investigation》1987,23(1):54-59
Human seminal plasma from normal or patients with abnormal parameters of the ejaculates contains an inhibitory material that expresses potent in vitro inhibitory activity on PHA-M-induced blast transformation and NK activity. Using the test of inhibition of NK activity, the semen samples from individuals with higher concentrations of fructose had higher inhibitory activity. The results described herein suggest that inhibitory activity for blast transformation may be present in the prostatic fluid while the NK inhibition aspects are correlated with the vesicle-marker (fructose). Inhibition of the immune responses by human seminal plasma of the effector functions indicates the interesting implication that soluble factors may indirectly protect against or promote human autoimmune infertility disease. 相似文献
75.
C S Cleeland R K Portenoy M Rue T R Mendoza E Weller R Payne J Kirshner J N Atkins P A Johnson A Marcus 《Annals of oncology》2005,16(6):972-980
BACKGROUND: Cancer pain is highly prevalent and commonly undertreated. This study was designed to determine whether dissemination of a clinical protocol for pain management would improve outcomes in community oncology practices. PATIENTS AND METHODS: A pain management protocol was developed based on accepted guidelines. After baseline assessment, oncology practices were randomly assigned to 'analgesic protocol' (AP) sites, where oncologists implemented the guidelines in a group of lung or prostate cancer patients, or to 'physician discretion' (PD) sites, where customary treatment was continued. Patients treated on protocol and a comparison group of patients with pain due to breast cancer or myeloma were monitored for change in pain using the Brief Pain Inventory, and for change in other symptoms or mood. RESULTS: The protocol terminated early because of poor accrual. We compared groups using proportions of patients who had no or mild pain at follow-up. Although measures of protocol adherence did not suggest the occurrence of major practice change, the proportion of lung or prostate cancer patients with no or mild pain increased significantly from baseline for those treated at AP sites compared with those treated at PD sites. There was no significant difference between the breast and myeloma patients treated at AP sites versus those treated at PD sites. CONCLUSION: A protocol for cancer pain management can improve pain control. Diffusion of these benefits to other patients was not confirmed. Given the small sample size, these findings require confirmation in a larger trial. 相似文献
76.
77.
Molecular characterization of in vivo mutation at the human hypoxanthine phosphoribosyltransferase (hprt) locus has revealed a broad spectrum of mutation, both with regard to germ-line mutation in Lesch-Nyhan and gout patients, and somatic mutation in 6-thioguanine resistant T-lymphocytes from healthy individuals. The pattern of missense mutation shows a non-random distribution with a preferential location to codons for amino acids which are identical in human and the two parasites Schistosoma mansoni and Plasmodium falciparum. Although these 'evolutionary conserved' amino acids account for only 32% of the amino acids in the human hprt protein, they are involved in 76% of the missense mutations at the hprt locus in human T-lymphocytes, 67% in Lesch-Nyhan patients (with severe hprt-deficiency), but only 43% in gout patients (with partial hprt deficiency). This observation supports the notion that evolutionary conserved amino acids constitute functionally important sites in the hprt enzyme, and missense mutations affecting these amino acids will often lead to complete loss of enzyme activity. Substitutions of 'non-conserved' amino acids cause less severe hprt-deficiency (as seen in the gout patients), or may even escape clinical diagnosis. These considerations are important for the understanding of structure-activity relationships in the hprt protein, possible differences between hprt mutational spectra in germ-line and somatic cells, and the mutational spectra induced by specific exogeneous mutagens. 相似文献
78.
D. J. Weiss M. C. Bauer M. J. Murphy V. Perman 《Comparative Haematology International》1992,2(3):157-161
The mechanism responsible for the decreased red blood cell (RBC) lifespan associated with feeding propylene glycol (PG)-containing diets was investigated to understand better how Heinz body-contained RBC are destroyed. Three cats were fed a diet containing 12% PG for 14 days and three other cats served as control. The experimental group developed reticulocytosis and increased Heinz body numbers. Red blood cell membrane immunoglobulih G (IgG) concentration and phagocytosis of RBC by peritoneal macrophages were lower in the PG group compared to the control group suggesting that neither IgG nor non-IgG-mediated phagocytosis was responsible for the RBC destruction. Osmotic fragility, rate of RBC proteolysis and mild mechanical fragility test results were not statistically different from controls. However, when RBC from cats fed PG were exposed to severe mechanical stress, their fragility were increased 2.2–2.8 times. Additionally, haptoglobin concentrations were decreased in the PG group. These data suggest that intravascular lysis may be involved in the pathogenesis of PG-induced RBC destruction. 相似文献
79.
Nancy Kluck Sean O'Connor Victor Hesselbrock Allan Tasman Donald Maier Lance Bauer 《Progress in neuro-psychopharmacology & biological psychiatry》1992,16(6):901-911
Nancy Kluck, Scan J. O'Connor, Victor M. Hesselbrock, Allan Tasman and Donald Maier, Lance Bauer: Variation in Evoked Potential Measures Over the Menstrual Cycle: A Pilot Study. Prog. Neuro. Psychopharmacol. Biol. Psychiat. 1992. 16(6): 901–911.
1. 1. The P3 component of a visual event related potential (ERP) was studied for five consecutive weeks in six women with normal menstrual cycles. Serum concentrations of luteinizing hormone (LH), estradiol (E2) and progesterone were studied during the same period.
2. 2. Increases in P3 amplitude, although nonsignificant, were noted in the week preceding onset of menses.
3. 3. No significant changes in reaction times to target/nontarget stimuli were noted over the same time period.
80.
Calculations of radiation flux and dose distributions for boron neutron capture therapy (BNCT) of brain tumors are typically performed using sophisticated three-dimensional analytical models based on either a homogeneous approximation or a simplified few-region approximation to the actual highly heterogeneous geometry of the irradiation volume. Such models should be validated by comparison with calculations using detailed models in which all significant macroscopic tissue heterogeneities and geometric structures are explicitly represented as faithfully as possible. This paper describes such a validation exercise for BNCT of canine brain tumors. Geometric measurements of the canine anatomical structures of interest for this work were performed by dissecting and examining two essentially identical Labrador retriever heads. Chemical analyses of various tissue samples taken during the dissections were conducted to obtain measurements of elemental compositions for the tissues of interest. The resulting geometry and tissue composition data were then used to construct a detailed heterogeneous calculational model of the Labrador head. Calculations of three-dimensional radiation flux distributions pertinent to BNCT were performed for this model using the TORT discrete-ordinates radiation transport code. The calculations were repeated for a corresponding volume-weighted homogeneous-tissue model. Comparison of the results showed that peak neutron and photon flux magnitudes were quite similar for the two models (within 5%), but that the spatial flux profiles were shifted in the heterogeneous model such that the fluxes in some locations away from the peak differed from the corresponding fluxes in the homogeneous model by as much as 10%-20%. Differences of this magnitude can be therapeutically significant, emphasizing the need for proper validation of simplified treatment planning models. 相似文献