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1.
Uroscopy in the 21st century: high-field NMR spectroscopy   总被引:1,自引:1,他引:0  
From the experiments described, it can be seen that there are different research approaches that can be taken and these are summarized in Table 1. Whereas much scientific research is principally hypothesis led, there remains, nevertheless, an important place for exploratory research. High resolution NMR can measure, directly and simultaneously, a wide range of endogenous metabolites in biological fluids and has the unique capability of providing structural information on the metabolites detected. It has proved to be a powerful research tool with which to study inherited metabolic diseases, renal disease, drug metabolism, and toxicity, and can be used to monitor the effects of drug therapy. For instance, by using a library of experimental toxins one can map the metabolic profile of site-specific nephron injury. With this approach in man one could eventually take an unknown disease such as Balkan nephropathy and predict the initial site of tubular injury, the mode of injury and therefore the kind of toxin capable of producing that injury. NMR spectroscopic techniques are still advancing rapidly, with ever increasing sensitivity and sophistication of NMR pulse sequences to enhance structural elucidation in complex mixtures. Given the advances in directly coupled HPLC-NMR and even HPLC-NMR-mass spectroscopy it is likely that these technologies in conjunction with pattern recognition will make major contribution to our understanding of renal processes and provide new diagnostic insights in the 21st century.   相似文献   
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Age-hardening mechanisms and related ordering behaviors of the experimental (AuCu)1−xZnx alloys with x0.2 were investigated for dental applications. The addition of Zn to equiatomic AuCu greatly increased the age-hardening rate and delayed overaging. It was suggested that the quenched-in excess vacancies were greatly related to the age-hardening rate in the AuCu–Zn pseudobinary alloys. In these alloys, the hardness became maximum during the very initial stage of ordering, and with the development of ordered phase, the hardness began to decrease. Transmission electron microscopy revealed that the age-hardening of AuCu–Zn pseudobinary alloys is caused by lattice distortion that occurred during the very early stage of atomic ordering. The addition of Zn to AuCu effectively increased the density of antiphase boundaries per unit volume of the AuCu II superstructure. This is suggested to be the main cause for the retardation of the overaging in the alloys containing Zn of 5 at% or more. This pronounced effect of Zn addition to AuCu alloy on its age-hardening characteristics may be advantageous for obtaining stable mechanical properties of dental casting gold alloys.  相似文献   
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Advanced adipose-derived stem cell protein extracts (AAPE) were used instead of live stem cells to investigate their effect on oxidative stress and matrix metalloproteinases (MMPs) related to tissue repair in human dermal fibroblasts (HDFs). In this study, it was observed that AAPE at 2μg/ml specifically exhibited scavenging activity of hydrogen peroxide and reducing power. The inhibitory effect of AAPE at 2μg/ml on MMP-2 activity was increased in the presence of phorbol myristate acetate (PMA). In the absence of PMA, AAPE significantly enhanced activities of MMP-1 and MMP-2 in HDFs, respectively. However, the level of MMP-1 expression was decreased in a dose dependent manner by AAPE. In addition, while the level of extracellular signal-regulated kinases 1 (ERK1) activation was reduced in the presence of AAPE compared to blank, the level that of ERK2 activation was not changed. The expression level of c-Fos, a part of activator protein-1 (AP-1), was increased in nucleus of HDFs. These results reveal that activation of MMPs in the presence of AAPE was increased via AP-1 in HDFs, suggesting that AAPE can be a potential candidate for tissue repair.  相似文献   
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Immunosuppressive therapy (IST) has provided an alternative treatment option for cure of aplastic anemia patients who cannot receive bone marrow transplantation. Although there have been many recent studies on the efficacy of antithymoglobulin (ATG) combined with cyclosporine A (CsA), there is no data on the correlation between the variability of CsA levels and the response to IST. Therefore, we retrospectively assessed the factors associated with IST efficacy in patients with acquired severe aplastic anemia (SAA). Sixty‐six patients were treated with ATG combined with CsA for 6 months. In the response group, the CsA levels were increased rapidly to more than 200 ng/mL within the first 2 wk after starting the IST. However, the non‐response group had a pattern of slower increase of the CsA levels. The CsA levels, during the first and second week of treatment with IST, were significantly different in the responders and non‐responders. The factors predictive of response to IST and survival were analyzed. The univariate analysis showed that a younger age at the initiation of IST, a high absolute neutrophil count prior to starting IST, a short interval between the diagnosis and initiation of IST, and high CsA levels during the first and second week of IST treatment were positively associated with the response rate and overall survival. The multivariate analysis showed that these four factors were independent factors associated with a longer patient survival. A high response rate was associated with a short interval between diagnosis and initiation of IST as well as high CsA levels during the first and second week of IST. Therefore, early intensification of CsA levels might improve patient outcome.  相似文献   
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Gestational diabetes mellitus (GDM) is a strong predictor of postpartum prediabetes and transition to overt type 2 diabetes (T2DM). Although many reports indicate that low magnesium is correlated with deteriorated glucose tolerance, the association between postpartum serum magnesium level and the risk for T2DM in women with a history of GDM has not been evaluated. We analyzed postpartum serum magnesium levels and development of prediabetes and T2DM in women with prior GDM according to American Diabetes Association (ADA) criteria using the Korean National Diabetes Program (KNDP) GDM cohort. During a mean follow-up of 15.6±2.0 months after screening, 116 women were divided into three groups according to glucose tolerance status. Ultimately, eight patients (6.9%) were diagnosed with T2DM, 59 patients (50.9%) with prediabetes, and 49 patients (42.2%) with normal glucose tolerance (NGT) after follow-up. The T2DM group had the lowest serum magnesium level (0.65 [0.63-0.68] mM/L) in the postpartum period, but there was no significant difference between the prediabetes group (0.70 [0.65-0.70] mM/L) and the NGT group (0.70 [0.65-0.70] mM/L) (P=0.073) Multiple logistic regression analysis showed that postpartum HOMA-IR was a significant predictor of both prediabetes and T2DM. Moreover, we found that postpartum serum magnesium level was also a possible predictor for T2DM development. Serum magnesium level in the postpartum period may be a possible predictor for T2DM development in women with a history of GDM.  相似文献   
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