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1.
Excessive energy intake may evoke complex biochemical processes characterized by inflammation, oxidative stress, and impairment of mitochondrial function that represent the main factors underlying noncommunicable diseases. Because cow milk is widely used for human nutrition and in food industry processing, the nutritional quality of milk is of special interest with respect to human health. In our study, we analyzed milk produced by dairy cows fed a diet characterized by a high forage:concentrate ratio (high forage milk, HFM). In view of the low n-6:n-3 ratio and high content of conjugated linoleic acid of HFM, we studied the effects of this milk on lipid metabolism, inflammation, mitochondrial function, and oxidative stress in a rat model. To this end, we supplemented for 4 wk the diet of male Wistar rats with HFM and with an isocaloric amount (82 kJ, 22 mL/d) of milk obtained from cows fed a diet with low forage:concentrate ratio, and analyzed the metabolic parameters of the animals. Our results indicate that HFM may positively affect lipid metabolism, leptin:adiponectin ratio, inflammation, mitochondrial function, and oxidative stress, providing the first evidence of the beneficial effects of HFM on rat metabolism.  相似文献   
2.
The authenticity and traceability of meat products are issues of primary importance to ensure food safety. Unfortunately, food adulteration (e.g. the addition of inexpensive cuts to minced meat products) and mislabelling (e.g. the inclusion of meat from species other than those declared) happens frequently worldwide. The aim of this study was to apply a droplet digital PCR assay for the detection and quantification (copies μL−1) of the beef, pork, horse, sheep, chicken and turkey in meat products. The analysis conducted on commercial meat showed the presence of traces of DNA from other animal species than those declared. We show that the method is highly sensitive, specific and accurate (accuracy = 100%). This method could be adopted by competent food safety authorities to verify compliance with the labelling of meat products and to ensure quality and safety throughout the meat supply chain, from primary production to consumption.  相似文献   
3.

Background  

Excess body fat is a major risk factor for disease primarily due to its endocrine activity. In recent years several criteria have been introduced to evaluate this factor. Nevertheless, treatment need is currently assessed only on the basis of an individual's Body Mass Index (BMI), calculated as body weight (in kg) divided by height in m2. The aim of our study was to determine whether application of the BMI, compared to adiposity-based criteria, results in underestimation of the number of subjects needing lifestyle intervention.  相似文献   
4.
Features of the electrochemical reduction of nitric oxide on platinum, palladium, rhodium and ruthenium in aqueous perchloric acid solutions (0.33–1.0 M) are compared. The results from voltammetric studies (ie linear potential sweep and rotating disc electrode) using the bulk metal electrodes are described and compared with residual current voltage plots in acid electrolyte alone. In general, three nitric oxide reduction peaks are observed on the metals. The most anodic peak, at ca E = 0.15 V vs sce is attributed to the one-electron reduction of nitric oxide to an adsorbed NOH intermediate on a bare metal surface (ie one free of oxides or adsorbed hydrogen). The other two peaks occur in potential regions where adsorbed hydrogen is present on the metal surface (ca E = 0.0 and −0.20 V, respectively). The co-adsorbed hydrogen complicates the analysis and precludes an unambiguous interpretation of these two peaks. However, they apparently reflect nitric oxide reduction to nitrogen, hydroxylamine and/or ammonia. In a cathodic scan on the rhodium electrode, a current plateau is seen instead of the first (most anodic) peak, a probable consequence of oxide film formation with subsequent chemical complications. On the ruthenium electrode the first two (most anodic) peaks are not observed probably due to a relatively stable oxide layer. Reaction selectivities at metal black gas diffusion cathodes operating in an electrogenerative (ie galvanic) mode with perchloric acid electrolyte are compared with the voltammetric results at the corresponding bulk electrodes. Dinitrogen formation is observed on the platinum and rhodium black electrodes as suggested from voltammetric results. A series-parallel reaction sequence is proposed to explain the results. Limitations of using simple voltammetric techniques for predicting behavior of large scale preparative electrochemical reactors are discussed.  相似文献   
5.
The internal anal sphincterotomy operation represents the best therapy for the treatment of those anal lesions, above all anal fissures, which cause hypertrophy and spasms of the internal anal sphincter. The Authors report their experience of 253 operations of internal subcutaneous sphincterotomy carried out between 1989 and 1995 under local anaesthesia in the outpatient clinic. The excellent results achieved prove that the procedure can easily be carried out under local anaesthesia in an outpatient clinic and, therefore, it is preferable to the surgical technique of isolation of the internal sphincter, not only for its practicality but also for the improved results.  相似文献   
6.
Integrins mediate cell adhesion and can induce different cellular responses, including changes in intracellular pH, changes and oscillation in intracellular free calcium, and protein phosphorylation on tyrosine. During bone resorption, the integrin alphav beta3 regulates adhesion of osteoclasts to bone extracellular matrix proteins, such us osteopontin (Opn). Adhesion via alphav beta3 is followed by osteoclast polarization onto the bone surface and by the onset of bone resorption. To characterize these events at the molecular level, we investigated the state of activation of alphav beta3 on the human osteoclast-like cell line GCT23 using the monoclonal antibody AP5 which binds to and can induce, under low calcium conditions, activated alphav beta3. By flow cytometry, approximately 50% of alphav beta3 on the surface of the osteoclast-like cell line GCT23 was reactive with AP5 and was therefore in the activated state. Incubation with AP5 in the presence of low calcium concentrations increased activated alphav beta3 to 90-100%. Activation of alphav beta3 increased the efficiency of GCT23 adhesion to Opn by 2-fold. Furthermore, haptotactic migration on Opn was also enhanced about 40% compared to control. We propose that changes in the activation state of alphav beta3 may be a regulation point for osteoclasts during bone resorption.  相似文献   
7.
The precise measurement of low numbers of leukocyte below 0.1 WBC/microliter in filtered red cell or platelet suspensions meet both aims: to check the compliance with previously determined requirements and to evaluate the performances of novel filtering material (5 log depletion or more), justified by more and more important clinical use. The reliability of results, obtained with the chosen method, is ensured by applying of validation protocol, including training of technologist, assessment of the analytical range and the detection limit, assessment of precision and accuracy. The flow cytometry (FC) and Nageotte Chamber (NC) method are the both techniques which are currently used in routine Quality Control (QC) and validated by multicenter studies. Recent developments are made for increasing the sensibility of these counting methods, thanks to higher concentration or volume of the sample to be analysed. Among the experimental techniques, requiring more advances before implementing in QC program, quantitative PCR must become essential as reference method for evaluating the efficiency of filtration, in the future.  相似文献   
8.
The aim of the study was to test the hypothesis that magnetic resonance (MR) imaging-guided and -monitored noninvasive ultrasonic surgery can be performed in highly perfused tissues from outside the body. A simulation study was performed to evaluate the optimal sonication parameters. An MR-compatible positioning device was then used to manipulate a focused ultrasound transducer in an MR imager, which was used to sonicate kidneys of five rabbits at various power levels and different durations. Temperature elevation during sonication was monitored with a T1-weighted spoiled gradient-echo sequence. The simulation study demonstrated that a sharply focused transducer and relatively short sonication times (30 seconds or less) are necessary to prevent damage to the overlying skin and muscle tissue, which have a much lower blood perfusion rate than kidney. The experiments showed that the imaging sequence was sensitive enough to show temperature elevation during sonication, thereby indicating the location of the beam focus. Histologic evaluations showed that kidney necrosis could be consistently induced without damage to overlying skin and muscle. The study demonstrated that highly perfused tissues such as the renal cortex can be coagulated from outside the body with focused ultrasound and that MR imaging can be used to guide and monitor this surgery.  相似文献   
9.
This work presents a numerical study of high-field degradation and reliability issues of AlGaAs/GaAs power HFETs. A commercial two-dimensional drift–diffusion tool is used to investigate electric-field distributions, the effects of electron capture at the device surface under hot-carrier conditions, and the impact of drain recess scaling on such effects. Wherever experimental data are available for direct comparison, a good match is observed with our simulations. The main results of this study are (1) a validation of the hypothesis that attributes the main high-field degradation effects to electron capture over the gate–drain access region, and (2) design indications pointing out to the possibility of a reverse correlation between the gate–drain breakdown voltage and the device hot-carrier reliability.  相似文献   
10.
Investigated the development of spontaneous classificatory behavior in 5 chimpanzees (Pan troglodytes) tested at different ages and analyzed Ss' spontaneous constructive interactions with sets of logically structured objects. The results show that chimpanzees possess a natural capacity to react to similarities and differences among test stimuli and construct classes. The general progression of their classificatory development is very similar to that reported for human infants from 6 to 24 mo. In both species, classification progresses from constructing single classes by different properties of objects to constructing single classes by similar or identical properties of objects. In addition, like humans, older chimpanzees spontaneously coordinate relations of similarities between sets and construct 2 class-consistent groupings. Chimpanzees' results are compared with those from a similar study with capuchins and macaques. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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