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91.
92.
Marrow graft failure observed in association with histocompatibility differences between donor and recipient is often attributed to rejection mediated by host-derived cytolytic T lymphocytes. The data presented in this report indicate that persistent host antibodies specific for donor antigen may also mediate graft failure, either by antibody-dependent cell-mediated cytotoxicity (ADCC), or complement- mediated cytotoxicity. In the case of HLA Class I disparity, where all donor cells express the target antigen, the presence of alpha-donor antibody was associated with complete graft failure and death. In the case of ABO blood group antigen disparity, the presence of alpha-donor antibody resulted in erythroid hypoplasia. The latter cases proved informative insofar as they established that host antibodies could persist for more than 18 months after chemoradiotherapy and impair marrow function. 相似文献
93.
SUMMARY Impotence is a common symptom which can cause considerable distress to both the sufferer and his partner. The use of pharmacotherapy to improve erectile function will continue to increase as safe and effective drugs are developed. However, restoring erectile function should not be the only treatment objective. It is also essential to address personal and emotional factors in the sufferer, conflicts in his relationship with his partner, and sexual problems in his partner, all of which may be instrumental in causing or maintaining the presenting impotence. We advocate a combined approach with appropriate medical treatment and sex and couple therapy 相似文献
94.
Bronwyn Myers Nastassja Koen Kirsten A. Donald Raymond T. Nhapi Lesley Workman Whitney Barnett Nadia Hoffman Sheri Koopowitz Heather J. Zar Dan J. Stein 《Alcoholism, clinical and experimental research》2018,42(2):369-377
Background
Cohort studies have noted associations between hazardous alcohol use during pregnancy and infant growth outcomes, but many have not controlled for potential psychosocial confounders. To assess the unique contribution of hazardous alcohol use, we examined its effect on infant growth outcomes while controlling for maternal psychosocial stressors and hazardous tobacco and drug use in a cohort of 986 pregnant South African women enrolled into the Drakenstein Child Health Study between 2012 and 2015.Methods
Data on psychosocial stressors and maternal risk behaviors were collected between 28 and 32 weeks of gestation. Participants were categorized as hazardous alcohol users if they obtained moderate or high scores (>10) on the Alcohol, Smoking and Substance Involvement Screening Test at this assessment or retrospectively reported drinking at least 2 drinks weekly during any trimester of pregnancy. Infant growth outcomes were recorded at delivery. Multivariable regression models examined correlates of hazardous alcohol use and associations between hazardous alcohol use and birth outcomes.Results
Overall, 13% of mothers reported hazardous alcohol use. Recent exposure to intimate partner violence (adjusted odds ratio (aOR) = 2.08; 95% confidence interval (CI): 1.37, 3.18) and hazardous tobacco use (aOR = 5.03; 95% CI: 2.97, 8.52) were significant correlates of hazardous alcohol use. After controlling for potential psychosocial confounders, hazardous alcohol use remained associated with lower infant weight‐for‐age (B = ?0.35, 95% CI: ?0.56, ?0.14), height‐for‐age (B = ?0.46, 95% CI: ?0.76, ?0.17), and head‐circumference‐for‐age z‐scores (B = ?0.43, 95% CI: ?0.69, ?0.17).Conclusions
Interventions to reduce hazardous alcohol use among pregnant women in South Africa are needed to prevent alcohol‐related infant growth restrictions. As these growth deficits may lead to neurodevelopmental consequences, it is critical to identify alcohol‐related growth restrictions at birth and link exposed infants to early interventions for neurodevelopment.95.
96.
97.
Eosinophil functions can be modulated by several cytokines such as granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin- 3 (IL-3), and IL-5. We have investigated the modulatory role of these cytokines on the interaction of human eosinophils with opsonized particles (serum-treated zymosan [STZ]). Addition of STZ to eosinophils isolated from the peripheral blood of normal human donors resulted in an interaction of the STZ particles with only 15% to 25% of the cells. Treatment of the eosinophils with GM-CSF, IL-3, or IL-5 strongly enhanced both the rate of particle binding and the percentage of eosinophils binding STZ. The effect of the cytokines is most likely mediated by a change in affinity of the complement receptor type 3 (CR3) on the eosinophils for the complement fragment iC3b on the STZ particles. This is indicated by the observation that (1) the effect of the cytokines on STZ binding was prevented by a monoclonal antibody against the iC3b-binding site on CR3 and (2) the enhanced binding was already apparent before upregulation of CR3 on the cell surface was observed. In a previous study, similar results were obtained with platelet-activating factor (PAF)-primed eosinophils. Because we found that the cytokines strongly enhanced the STZ-induced PAF synthesis, we investigated the role of both released PAF and cell-associated PAF in the priming phenomenon by the cytokines. Cytokine priming appeared to be largely independent of the synthesis of PAF. 相似文献
98.
Physiologic regulation and tissue localization of renal erythropoietin messenger RNA 总被引:7,自引:0,他引:7
Although erythropoietin (Epo) is produced primarily by the kidneys in response to hypoxia, the precise cell type(s) and mechanisms by which these cells regulate production are poorly understood. In the experiments we report, the kinetics of renal Epo production in response to acute hypoxia and the intrarenal localization of cellular Epo synthesis were studied at the level of Epo mRNA. Erythropoietin mRNA expression was determined by Northern blot analysis of rat kidney RNAs using a probe derived from the mouse Epo gene. Renal Epo mRNA content increased as early as 1 hour after initiation of hypoxia and continued to accumulate during 4 hours of stimulation. Discontinuation of the hypoxic stimulus resulted in rapid decay of mRNA levels. Kidney and plasma Epo levels measured by radioimmunoassay paralleled, with respective lag times, the changes in renal Epo mRNA content, suggesting that Epo production in response to acute hypoxia represents de novo synthesis and is regulated by changes in Epo mRNA. Northern blot analysis of RNAs extracted from separated glomerular and tubular tissue fractions revealed Epo mRNA in the tubular fraction, whereas glomerular tissue did not contain Epo mRNA. Thus, the site of cellular Epo synthesis is located in the renal tubule or its interstitium and not in the glomerular tuft. 相似文献
99.
Jessurun GA Hautvast RW DeJongste MJ Meyler WJ van Boven AJ Crijns HJ 《The Journal of invasive cardiology》1999,11(7):435-438
Patients with symptomatic small vessel coronary artery disease may be inadequate candidates for revascularization procedures. They may suffer from refractory angina, which does not respond to maximal anti-anginal drug therapy. In addition to patients with end stage coronary artery disease and syndrome X, this newly defined group of subjects with an isolated stenosis of a small coronary artery may benefit from electrical neurostimulation. We describe two patients with intractable angina caused by a significant narrowing of a diagonal branch. This treatment modality should be considered as an alternative method for unsatisfactory revascularization procedures. 相似文献
100.
Minimal variation in T-20 binding domain of different HIV-1 subtypes from antiretroviral-naive and -experienced patients 总被引:2,自引:0,他引:2
Xu L Hué S Taylor S Ratcliffe D Workman JA Jackson S Cane PA Pillay D 《AIDS (London, England)》2002,16(12):1684-1686
In-vitro differences in T-20 susceptibility among HIV-1 subtypes have been reported. We therefore studied the T-20 binding domain of a variety of virus subtypes from both antiretroviral-naive and -experienced patients. Minimal variation in the HR-1 region of gp41 was observed, especially within the region responsible for T-20 resistance. Any subtype differences in T-20 susceptibility do not appear to be related to HR-1 genetic variation. 相似文献