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981.
体外受精-胚胎移植(试管婴儿)是辅助生育技术的核心部分,也是现代医学发展中治疗不孕不育症的先进技术[1].自1978年世界上第1例试管婴儿诞生以来,目前已有400万试管婴儿出生,使不孕夫妇看到希望.但是特殊的受孕方式、身心背景、经济压力,给病人造成极大的心理压力,易引起许多心理疾患[2].我们通过对接受体外受精-胚胎移植病人进行针对性心理护理,使其丢掉思想包袱,积极配合治疗,增强自信心,以便获得最佳疗效.现报告如下.  相似文献   
982.
Adjuvants are becoming the key players of vaccine formulations to enhance the immunogenicity of subunit (peptides, proteins, virus-like particles (VLPs)) and DNA vaccines, as well as to reach the current new goals of preventing and/or treating chronic infectious diseases and cancers. Induction of humoral response, in particular neutralizing antibodies able to inhibit the binding of pathogens to their cellular receptors, remains a major goal of vaccines targeted to prevent acute lytic infections; induction/modulation of cellular immunity is, however, critical to fight latently/chronically infected cells as well as cancer cells. The new adjuvants, included in vaccine preparations, are currently able to modify the presentation of epitopes to the immune system with a specific T(H)1 versus T(H)2 polarization efficacy. A paradigm of the relevance of these new adjuvants is the immunological result obtained with the inclusion of monophosphoryl lipid A in the formulation of L1-based human papillomavirus (HPV)-naked VLPs. In the May issue of this journal, Garcon and colleagues describe the highly enhanced humoral and memory B cellular immunity of the AS04-adjuvanted HPV vaccine, which results in a long-lasting and broad spectrum immunity.  相似文献   
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984.
Although organ transplants have been applied for decades, outcomes of somatic cell transplants remain disappointing, presumably due to lack of appropriate supporting stromal cells. Thus, cotransplantation with liver stromal cells, hepatic stellate cells (HSC), achieves long-term survival of islet allografts in mice by way of induction of effector T cell apoptosis and generation of regulatory T (Treg) cells. In this study we provide evidence both in vitro and in vivo that HSC can promote generation of myeloid-derived suppressor cells (MDSC). HSC-induced MDSC demonstrate potent immune inhibitory activity. Induction of MDSC is dependent on an intact interferon gamma signaling pathway in HSC and is mediated by soluble factors, suggesting that the specific tissue stromal cells, such as HSC, play a crucial role in regulating immune response by way of inflammation-induced generation of MDSC. Large amounts of MDSC can be propagated in vitro from bone marrow-derived myeloid precursor cells under the influence of HSC. CONCLUSION: Cotransplantation with in vitro generated MDSC can effectively protect islet allografts from host immune attack. Local delivery of potent immune suppressor cells for cell transplants holds great clinical application potential.  相似文献   
985.
986.
The interactions between the renin-angiotensin system and neovascularization in atherosclerotic plaque development are unclear. We investigated the effects of angiotensin II type 1 receptor antagonism in the pathogenesis of atherosclerosis in apolipoprotein E-deficient (ApoE(-/-)) mice with a special focus on plaque neovascularization. ApoE(-/-) mice fed a high-fat diet were randomly assigned to 1 of 2 groups and administered vehicle or olmesartan for 12 weeks. Quantification of plaque areas at the aortic root and in the thoracic and abdominal aorta revealed that, in all 3 of the regions, olmesartan reduced intimal neovessel density and the mRNA levels of toll-like receptor (TLR) 2 and TLR4. Olmesartan increased the levels of collagen and elastin, reduced the level of macrophages in the aortic root, and reduced the mRNA and the activity of matrix metalloproteinase (MMP) 2 in aortic roots and thoracic aortas. Aortic ring assay revealed that olmesartan-treated ApoE(-/-) mice had a markedly lower angiogenic response than that of untreated ApoE(-/-) mice. Bone marrow-derived endothelial progenitor cell-like c-Kit(+) cells from olmesartan-treated ApoE(-/-) mice showed marked impairment of cellular functions and lower expression of TLR2/TLR4 and MMP-2 compared with those of untreated controls. MMP-2 deficiency reduced intimal neovessel density and atherosclerotic lesion formation. Olmesartan and small-interfering RNA targeting TLR2 reduced the levels of TLR2, and MMP-2 mRNA induced angiotensin II in cultured endothelial cells. Angiotensin II type 1 receptor antagonism appears to inhibit intimal neovascularization in ApoE(-/-) mice, partly by reducing TLR2/TLR4-mediated inflammatory action and MMP activation, thus decreasing atherosclerotic plaque growth and increasing plaque instability.  相似文献   
987.
Binding of blood proteins to carbon nanotubes reduces cytotoxicity   总被引:2,自引:0,他引:2  
With the potential wide uses of nanoparticles such as carbon nanotubes in biomedical applications, and the growing concerns of nanotoxicity of these engineered nanoparticles, the importance of nanoparticle-protein interactions cannot be stressed enough. In this study, we use both experimental and theoretical approaches, including atomic force microscope images, fluorescence spectroscopy, CD, SDS-PAGE, and molecular dynamics simulations, to investigate the interactions of single-wall carbon nanotubes (SWCNTs) with human serum proteins, and find a competitive binding of these proteins with different adsorption capacity and packing modes. The π-π stacking interactions between SWCNTs and aromatic residues (Trp, Phe, Tyr) are found to play a critical role in determining their adsorption capacity. Additional cellular cytotoxicity assays, with human acute monocytic leukemia cell line and human umbilical vein endothelial cells, reveal that the competitive bindings of blood proteins on the SWCNT surface can greatly alter their cellular interaction pathways and result in much reduced cytotoxicity for these protein-coated SWCNTs, according to their respective adsorption capacity. These findings have shed light toward the design of safe carbon nanotube nanomaterials by comprehensive preconsideration of their interactions with human serum proteins.  相似文献   
988.
989.
990.
Simultaneous recordings of Electro-EncephaloGraphy (EEG) with Near InfraRed Spectroscopy (NIRS) allow measuring hemodynamic changes (changes in the concentration of oxy- and deoxyhemoglobin) at the time of epileptic discharges detected on scalp EEG. Two NIRS detection methods based on the General Linear Model (GLM) respectively in the time domain and in the time-frequency domain are investigated in this study using realistic simulations of spontaneous interictal epileptic activity. We evaluated the sensitivity at different Signal to Noise Ratios (SNR), the effect of either a large or a small number of discharges and the impact of model misspecification (e.g. omission or false detection of epileptic discharges). We also explored the effect on the estimation of key parameters, which set the model order. Simulations showed that both methods become inaccurate in lower SNR conditions, leading to many false positive detections. However, the time-frequency estimator showed better performance than the time-domain one. Key parameters for each algorithm were identified and results suggest to model confounds in the GLM differently for oxy- and deoxyhemoglobin. We also demonstrated that an inaccurate marking of epileptic events has a small impact on the detection statistics whereas an inaccurate specification of the hemodynamic response function delay decreases drastically the detection abilities. Finally, we illustrated the two methods on clinical EEG/NIRS data of one patient with focal epilepsy, showing an increase of regional Cerebral Blood Volume (rCBV) spatially concordant with the presumed epileptogenic focus.  相似文献   
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