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We present a novel approach to transient Raman spectroscopy, which combines stochastic probe pulses and a covariance-based detection to measure stimulated Raman...  相似文献   
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Although considerable experimental evidence suggests an important role of polyamines in breast cancer biology, compelling supportive data in patients are lacking. To address this issue, we measured ornithine decarboxylase (ODC), S-adenosylmethionine decarboxylase, and spermidine/spermine acetyltransferase (the three key polyamine metabolic enzymes) in a cohort of 50 primary human breast cancers and related their levels of activity to disease-free survival and overall survival. The major finding of our study was that ODC activity level was a negative independent prognostic factor for both end points. With regard to overall survival, the adverse influence of ODC expression was superior even to that provided by the number of positive nodes. Furthermore, the statistical significance of the ODC effect on survival was enhanced when breast cancer-specific mortality was included in the analysis as opposed to death from any cause. In addition, high tumor ODC activity may predict a shorter time from recurrence to death, although this effect was of only borderline statistical significance. In summary, these results provide the first concrete evidence supporting the prognostic role of ODC in human breast cancer.  相似文献   
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Reduced antibody-dependent cell-mediated cytotoxicity (ADCC) was demonstrated in lymphocytes of patients with rheumatoid arthritis (RA). Rheumatoid factor (RF) positive sera inhibited ADCC of normal lymphocytes by reacting both with effector and target cells (sensitized chicken red blood cells). These sera were fractionated by specific adsorption or gradient ultracentrifugation, and isolated RF or RF negative fractions were tested for their ability to inhibit ADCC by reacting with normal human lymphocytes or target cells. RF was ineffective on normal lymphocytes but it strongly inhibited the reaction by interaction with target cells. IgG RF negative fractions of certain sera were inhibitory by direct interaction with effector cells.  相似文献   
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In order to utilise sardinelle (Sardinellaaurita) protein by-products, which is normally discarded as industrial waste in the process of fish manufacturing, heads and viscera proteins were hydrolysed by different proteases to obtain antioxidative peptides. All hydrolysates showed different degrees of hydrolysis and varying degrees of antioxidant activities. Hydrolysate generated with crude enzyme extract from sardine (Sardinapilchardus) displayed high antioxidant activity, and the higher DPPH radical-scavenging activity (87 ± 2.1% at 2 mg/ml) was obtained with a degree of hydrolysis of 6%. This hydrolysate was fractionated by size exclusion chromatography on a Sephadex G-25 into eight major fractions (P1–P8). Fraction P4, which exhibited the highest DPPH scavenging activity, was then fractionated by reversed-phase high performance liquid chromatography (RP-HPLC). Seven antioxidant peptides were isolated. The molecular masses and amino acids sequences of the purified peptides were determined using ESI-MS and ESI-MS/MS, respectively. Their structures were identified as Leu-His-Tyr, Leu-Ala-Arg-Leu, Gly-Gly-Glu, Gly-Ala-His, Gly-Ala-Trp-Ala, Pro-His-Tyr-Leu and Gly-Ala-Leu-Ala-Ala-His. The first peptide displayed the highest DPPH radical-scavenging activity (63 ± 1.57%; at 150 μg/ml) among these peptides.  相似文献   
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Cheese yield is strongly influenced by the composition of milk, especially fat and protein contents, and by the efficiency of the recovery of each milk component in the curd. The real effect of milk composition on cheesemaking ability of goat milk is still unknown. The aims of this study were to quantify the effects of milk composition; namely, fat, protein, and casein contents, on milk nutrient recovery in the curd, cheese yield, and average daily yield. Individual milk samples were collected from 560 goats of 6 different breeds. Each sample was analyzed in duplicate using the 9-laboratory milk cheesemaking assessment, a laboratory method that mimicked cheesemaking procedures, with milk heating, rennet addition, coagulation, curd cutting, and draining. Data were submitted to statistical analysis; results showed that the increase of milk fat content was associated with a large improvement of cheese yield because of the higher recovery of all milk nutrients in the curd, and thus a higher individual daily cheese yield. The increase of milk protein content affected the recovery of fat, total solids, and energy in the curd. Casein number, calculated as casein-to-protein ratio, did not affect protein recovery but strongly influenced the recovery of fat, showing a curvilinear pattern and the most favorable data for the intermediate values of casein number. In conclusion, increased fat and protein contents in the milk had an effect on cheese yield not only for the greater quantity of nutrients available but also for the improved efficiency of the recovery in the curd of all nutrients. These results are useful to improve knowledge on cheesemaking processes in the caprine dairy industry.  相似文献   
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The aim of this research was to determine the content of the histidinic antioxidants, advanced glycation end products (pentosidine) and thiobarbituric acid reactive substance (TBARS) in the meat from different animal species. Carnosine, anserine, homocarnosine and pentosidine were quantified by HPLC/MS, while TBARS was determined by photometric measurements. The total CRCs (carnosine + anserine + homocarnosine) content was in the increasing order: beef < rabbit < pork < horse < chicken < turkey. The analysis showed traces of pentosidine above the instrumental determination limits in all the meat samples, while the susceptibility of these meat to lipid oxidation decreased from beef to chicken, with the exception of turkey meat, which presented a high TBARS content towards even though its total CRCs was the highest. The structure of homocarnosine was elucidated by high resolving power multistage mass spectrometry.  相似文献   
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