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61.
Spontaneous recurrent abortion (SRA) has been treated by means of immunization with paternal or third-party white blood cells, yet the immunological basis for SRA and for the role of immunization protocols in pregnancy outcome remains controversial. To elucidate this question, nine women with SRA were immunized with paternal mononuclear cells and studied before and 2 weeks after immunization. Seven women who became pregnant gave birth to live newborns. Secretion of the T helper 1 cytokines IL-2 and interferon- by patients' mononuclear cells decreased, while production of IL-10 increased. The levels of natural killer and lymphokine-activated killer cell-mediated cytotoxicity were markedly decreased. Monocyte functions such as secretion of IL-l, tumor necrosis factor a, IL-6, and cytotoxic activity decreased concurrently with elevations in IL-10 and transforming growth factor secretion. Production of IL-12, a pivotal regulatory cytokine, decreased. Furthermore, B7/1 expression on patients' mononuclear cells was downregulated. This resulted in a decrease in monocyte costimulatory activity of purified T cells with soluble anti-CD3, paralleled by a decline in allogeneic proliferative responses. These results suggest that the improved pregnancy success rate in women with SRA following immunization may be partly related to suppression of cell-mediated immunity and monocyte and natural killer cell activity.  相似文献   
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We view radiation therapy treatment planning (RTTP) as a problem of constrained optimization. In this context, the 'optimal' treatment is one that maximizes some objective function subject to the inherent constraints of the problem. We discuss two objective functions which are motivated by biological considerations rather than mathematical expedience. One of these measures the 'goodness' of a treatment in terms of its probability of success. The other measures the degree to which a treatment succeeds in satisfying a system of constraints that are mutually contradictory. We describe how to actually perform the optimization of these objective functions in practice and show some numerical results which demonstrate advantages of these objective functions over their more conventional counterparts.  相似文献   
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Our goal is to identify the genetic underpinnings of bicuspid aortic valve and aortopathy in Turner syndrome. We performed whole exome sequencing on 188 Turner syndrome study subjects from the GenTAC registry. A gene‐based burden test, SKAT‐O, was used to evaluate the data using bicuspid aortic valve (BAV) and aortic dimension z‐scores as covariates. This revealed that TIMP3 was associated with BAV and increased aortic dimensions at exome‐wide significance. It had been previously shown that genes on chromosome Xp contribute to aortopathy when hemizygous. Our analysis of Xp genes revealed that hemizygosity for TIMP1, a functionally redundant paralogue of TIMP3, increased the odds of having BAV aortopathy compared to individuals with more than one TIMP1 copy. The combinatorial effect of a single copy of TIMP1 and TIMP3 risk alleles synergistically increased the risk for BAV aortopathy to nearly 13‐fold. TIMP1 and TIMP3 are tissue inhibitors of matrix metalloproteinases (TIMPs) which are involved in development of the aortic valve and protection from thoracic aneurysms. We propose that the combination of TIMP1 haploinsufficiency and deleterious variants in TIMP3 significantly increases the risk of BAV aortopathy in Turner syndrome, and suggest that TIMP1 hemizygosity may play a role in euploid male aortic disease.  相似文献   
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ApoE genotype accounts for the vast majority of AD risk and AD pathology   总被引:9,自引:0,他引:9  
In this review, evidence is provided that apolipoprotein E (apoE) genotype accounts for the majority of Alzheimer's disease (AD) risk and pathology. The three major human isoforms, apoE2, apoE3, and apoE4, are encoded by different alleles (2, 3, 4) and regulate lipid metabolism and redistribution. ApoE isoforms differ in their effects on AD risk and pathology. Clinical and epidemiological data have indicated that the 4 allele may account for 50% of AD in the United States. Further, the rarity of AD among carriers of the 2 allele suggests that allelic variations in the gene encoding this protein may account for over 95% of AD cases. ApoE4 disrupts memory function in rodents. Further studies have indicated that fragments of apoE may contribute to both plaque and tangle formation. Thus, the epidemiologic and basic science evidence suggest that apoE genotype accounts for the vast majority of AD risk and pathology.  相似文献   
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The effect of the addition of small molecular weight anhydride oligomers to polymer microspheres was evaluated and increased bioadhesion of the composite was demonstrated. Blends of low molecular weight anhydride oligomers with thermoplastic poly(fumaric-co-sebacic anhydride) [p(FASA)] and polycaprolactone were examined. The effects of anhydride oligomers on polymer microsphere degradation, crystallinity, and surface morphology were also explored. The results demonstrated that fumaric anhydride oligomer remained within polymer microspheres for several hours after exposure to phosphate buffer, formed a homogenous crystalline blend, increased bioadhesion as measured on rat intestine, and enhanced drug delivery in vitro as measured by the everted sac technique.  相似文献   
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