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101.
1. Renal creatinine and inulin clearances were compared between sheep fed (a) high nitrogen and high energy diet; (b) low nitrogen and high energy diet and (c) low nitrogen and low energy diet. 2. Inulin clearance was significantly lower in sheep on both low nitrogen diets vs the group with high nitrogen intake. Differences were not ascertained between the groups on low nitrogen diets. 3. No significant differences were found in the creatinine clearance. The creatinine inulin clearance ratio was higher when animals were fed low nitrogen diets, vs the group on a high nitrogen diet. 4. Results suggest that the endogenous creatinine is not suitable for the GFR measurement in sheep under the different conditions of nutrition.  相似文献   
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The Sika deer antler is well known for its unique ability to regenerate repeatedly and grow rapidly. Furthermore, it is a precious traditional Chinese medicine and has been widely used for more than 20 centuries. The major bioactive components within the antlers are water-soluble proteins, polypeptides, and free amino acids. Many studies have shown that water-soluble antler extracts play pivotal roles in wound healing, immune system modulation, anti-oxidation, and anti-inflammation. However, the exact effects on chondrocytes are still largely unknown. In this study, we prepared fresh, aqueous extracts from growing deer antlers in a rapid growth stage. We isolated the chondrocytes from neonatal mouse rib cartilage and investigated the effects of antler extracts on chondrocyte viability. We also used the RNA-Seq method to analyze the gene expression pattern under antler extract treatment. We demonstrated that fresh extracts from Sika deer antlers in a rapid growth stage significantly promoted chondrocyte viability and kept chondrocytes proliferating continuously, while blocking maturation and further differentiation. Additionally, our results indicated that antler extracts might serve as a potent anti-oxidant, anti-inflammatory agent, and immune modulator to boost the abilities of chondrocytes against oxidative, inflammatory, and immune stresses. Thus, this study has greatly deepened our current knowledge of the molecular control of antler extracts on chondrocytes. It has also shed light on possible new strategies to further prevent and treat diseases of cartilage and other related diseases.  相似文献   
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Targeting phosphoinositide 3-kinase (PI3K) has been recognized as an attractive strategy for anticancer therapy. The PI3K is a heterodimer composed of a catalytic subunit p110 and a regulatory subunit p85. Here, instead of targeting the catalytic p110 that has been considered previously, we purposed targeting the peptide-recognition domain SH2 of regulatory p85 with natural medicines obtained by using a peptide scaffold-based screening scheme. In the procedure, a core binding motif was extracted from the cocrystallized complex of a cognate phosphopeptide with the domain, which was considered as basic scaffold to perform high-through virtual screening against a structurally diverse, nonredundant library of natural products. A number of hit compounds with high binding potency to the domain and significant conformational similarity with the peptide scaffold were identified; in vitro affinity assay confirmed that five hits have moderate or high affinity for the domain with measured dissociation constants Kd range between 25 and 360 μM, which are comparable to or even better than that of the cognate phosphopeptide SDpYMNMTP and its core motif peptide pYMNM (Kd?=?15 and 32 μM, respectively). Structural analysis and nonbonded comparison of SH2 interactions with phosphopeptides and potent hit compounds revealed that only negatively charged phosphate and, sometime, sulfate can confer domain-binding capability to small-molecule compounds, but carboxylate cannot. A similar binding mode of compounds with phosphopeptide is important for the compounds to have high affinity and specificity.  相似文献   
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Introduction: C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) which are used for assessment of axial spondyloarthritis (AxSpA) related disease activity have poor specificity and sensitivity. Neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio (PLR) and mean platelet volume (MPV) have not been investigated as disease activity markers among Asian AxSpA patients.

Methodology: A retrospective, cross-sectional study was conducted in Singapore General Hospital from January 2013 to December 2015 to investigate the role of NLR, PLR and MPV as disease activity markers in AxSpA patients.

Results: The mean age of patients (n?=?122) was 37.0?±?12.5 years old and majority of them were male (n?=?93, 76.2%). No significant differences were found between patients with disease with regards to age, gender, ethnicity, HLAB-27 status, age at onset of diagnosis of AxSpA, duration of disease and comorbidities such as cardiac disease (p?>?0.05).

There were no significant differences in the ESR, NLR, PLR and MPV between the four disease activity groups (p?>?0.05). However, patients with very high disease activity had higher ESR and CRP compared to patients with inactive disease and moderate disease activity (p?Conclusion: NLR, PLR and MPV were not associated with disease activity in Asian AxSpA patients.  相似文献   
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A study of chemically methylated deoxyribonucleic acid   总被引:8,自引:0,他引:8  
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