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For many parents stopping life-sustaining medical treatment on their dying infant is psychologically impossible. Dostoevsky's insights into human behavior, particularly the fact that individuals do not want the anxiety and guilt associated with responsibility for making difficult decisions, might change the way physicians approach parents for permission to withdraw life-prolonging medical interventions on dying infants.  相似文献   
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We compared two groups of patients with idiopathic epilepsy, 41 patients whose seizure frequency was not controlled by adequate therapy and 39 patients in good seizure control, in respect of hematology, kidney and liver function tests, serum IgG, IgA and IgM concentrations and drug concentrations. The only difference that emerged were in the serum immunoglobulins, which were raised in the drug refractory group, significantly (p less than 0.01) so in the case of IgG. Failure of seizure control did not depend on inadequacy of drug dose or of blood concentration. Although the serum Ig changes do not warrant the assumption of an immunological origin for drug resistance, they do suggest a useful research line.  相似文献   
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A cytomorphometric analysis of superficial vaginal cells inwomen in three groups of different types of hormonal concentrationwas made. There were 15 women in each group. Group I was studiedduring a natural cycle, group II under oral contraceptive therapyand group III during an in-vitro fertilization (IVF) stimulationprotocol. Morphometric parameters were measured on an imageanalyser. The area, perimeter and several form factors weremeasured separately for nuclei and cytoplasm. The nucleus:cytoplasmicratio was also determined. The cytoplasmic area was significantlyreduced in group II and was associated with a statisticallysignificant reduction of the nuclear area. The nucleus:cytoplasmicratio appeared significantly increased in group II and reducedin group III. Low oestradiol impregnation obtained with an oralminidosed contraceptive interfered with vaginal cell maturation.High oestradiol concentrations obtained during IVF protocolsinduced marked nuclear pycnosis but did not induce supra-physiologicalcell enlargement. Maximal cell size is genetically regulatedaccording to Driesch's law of volume invariance and hormonalover-stimulation has no effect on cell size. The nucleus:cytoplasmicratio appears to be a powerful parameter reflecting the oppositeeffects of hormones on cell compartments.  相似文献   
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The flow cytometric crossmatch and early renal transplant loss   总被引:3,自引:0,他引:3  
Data from this retrospective study indicate that a positive two-color T and/or B cell flow cytometric crossmatch (FCXM) is predictive of early renal allograft loss (less than 2 months) in cadaveric kidney donor recipients who had a negative crossmatch by the antihuman globulin complement-dependent cytotoxicity technique. Among 90 cadaveric kidney donor recipients (67 primary, 23 regrafts), 14 (8 primary, 6 regrafts) lost their renal allografts within 2 months, and 10 of the 14 were FCXM positive and HLA sensitized. The remaining 76 allografts survived beyond 2 months, 12 of which were FCXM-positive. Thus, the FCXM sensitivity rate for detecting early graft loss was 71%, and the specificity rate was 84%. Cadaveric graft-loss rates at 2 months were 33% for primary and 60% for FCXM-positive regrafts in contrast to 7% for primary and 0% for FCXM-negative regrafts. The difference in early graft loss between FCXM-positive and FCXM-negative recipients was statistically significant (P less than 0.0001). Subset analyses of FCXM-positive graft recipients indicate: (1) previous early graft loss contraindicates transplantation of an FXCM-positive regraft (P = 0.03); and (2) panel reactive antibody (PRA) less than or equal to 10% at crossmatch is not associated with early graft loss (P = 0.04). There was no significant difference in 1-year graft survival between primary and regrafts in either FCXM-negative recipients (85% vs. 77%, respectively) or FCXM-positive recipients (67% vs. 40%). All 12 of the FCXM-positive primary and regrafts that survived 2 months continued to function at 2 years. Stepwise logistic regression analysis of 5 independent predictor variables (FCXM status, gender, primary vs. regraft status, PRA level, and HLA mismatched antigens) indicated that the FCXM test was the best predictor of early graft loss. When FCXM results of the 90 cadaveric graft recipients were ranked in three groups, an FCXM channel shift of 29 or greater (third tertile) on a 1024 channel log scale was associated with a 7.0-fold (95% confidence interval 1.9-25.5) increased risk of early graft failure when compared to the first two tertiles. These data indicate that the FCXM offers an additional approach for identifying sensitized patients at risk of early renal allograft loss.  相似文献   
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Medifoxamine, an antidepressant agent which has an original chemical structure, has been shown through in vitro studies, utilising radioligand binding in tissue homogenates, to bind with moderately high affinity to 5-HT1c and 5-HT2 receptor subtypes and to 5-HT uptake sites (IC50 950, 980, and 1,500 nM, respectively). It has been shown to bind in vivo to rat brain 5-HT2 receptors after acute treatment with high dose (50 mg/kg, i.e., 133.9 μmol/kg). After 14 days continuous treatment with low dose (20 mg/kg, 53.6 μmol/kg), a decrease in the capacity of [3H]-5-HT uptake and a dose-dependent down-regulation of 5-HT2 receptors in rat cerebral cortex were observed. These results indicate that medifoxamine, which has been shown previously to act through dopaminergic systems, interacts also with central serotonergic neurotransmission and particularly with the 5-HT2 receptors, which could contribute to its antidepressant effect.  相似文献   
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