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排序方式: 共有180条查询结果,搜索用时 15 毫秒
61.
Serena Niro Alessandra Fratianni Patrizio Tremonte Elena Sorrentino Luca Tipaldi Gianfranco Panfili Raffaele Coppola 《Journal of dairy science》2014
This study assessed and compared the physicochemical, microbiological, and sensorial characteristics of Caciocavallo cheeses, made from cow milk and a mixture of cow with ewe or goat milk, during ripening. Different cheese-making trials were carried out on an industrial scale following the standard procedure of pasta filata cheeses, with some modifications. The percentage of the different added milk to cow milk influenced compositional and nutritional characteristics of the innovative products, leading to a satisfactory microbiological and sensorial quality. 相似文献
62.
Manerba M Vettraino M Fiume L Di Stefano G Sartini A Giacomini E Buonfiglio R Roberti M Recanatini M 《ChemMedChem》2012,7(2):311-317
One of the most prominent alterations in cancer cells is their strict dependence on the glycolytic pathway for ATP generation. This observation led to the evaluation of glycolysis inhibitors as potential anticancer agents. The inhibition of lactate dehydrogenase (LDH) is a promising way to inhibit tumor cell glucose metabolism without affecting the energetic balance of normal tissues. However, the success of this approach depends chiefly on the availability of inhibitors that display good selectivity. We identified a compound (galloflavin, CAS 568‐80‐9) which, in contrast to other inhibitors of human LDH, hinders both the A and B isoforms of the enzyme. To determine the mechanism of action, we collected LDH‐A and ‐B inhibition data in competition reactions with pyruvate or NADH and evaluated the results using software for enzyme kinetics analysis. We found that galloflavin inhibits both human LDH isoforms by preferentially binding the free enzyme, without competing with the substrate or cofactor. The calculated Ki values for pyruvate were 5.46 μM (LDH‐A) and 15.06 μM (LDH‐B). In cultured tumor cells, galloflavin blocked aerobic glycolysis at micromolar concentrations, did not interfere with cell respiration, and induced cell death by triggering apoptosis. To our knowledge, the inhibition of LDH is, to date, the only biochemical effect described for galloflavin. Because galloflavin is not commercially available, we also describe herein a procedure for its synthesis and report its first full chemical characterization. 相似文献
63.
64.
Cristiano Maria Verrelli Salvatore Pirozzi Patrizio Tomei Ciro Natale Stefano Bifaretti Alessandro Lidozzi 《International journal of control》2018,91(10):2147-2158
A master–slave synchronisation control problem is addressed for current-fed DC and permanent magnet synchronous motors with all uncertain parameters. A measurable exogenous rotor position reference signal, which belongs to the class of biased sinusoidal signals with uncertain bias, amplitude, angular frequency, phase, is to be tracked without assuming its a priori knowledge. An innovative modification of disturbance cancellation techniques allows to prove that an output feedback adaptive nonlinear control scheme, which simply generalises the classical internal-model-based input law, solves the aforementioned problem, with an overall stability proof concerning the entire closed-loop system. The practical effectiveness of the proposed approach is illustrated by experimental results. 相似文献
65.
Plasma concentrations of propoxyphene and its major metabolite, norpropoxyphene, were determined over at least 12 hr after oral administration of 130 mg dextropropoxyphene hydrochloride to eight men with hepatic cirrhosis, of whom four had a surgically constructed portacaval shunt, and to seven healthy men. Propoxphene concentrations were appreciably higher and norpropoxyphene concentrations were much lower in the patients than in the normal subjects. The ratio of areas under the plasma concentration-time curve from 0 to 12 hr, norpropoxyphene: propoxyphene, was 0.70 +/- 0.46 (x +/SD) in patients and 3.94 +/ 0.83 in normal subjects. A similar decrease in this ratio was observed previously in otherwise healthy dogs after surgical construction of portacaval shunt when propoxyphene was given orally, but not after intravenous injection of the drug. A woman with portacaval shunt and essentially complete renal failure was also studied; she exhibited the highest propoxyphene peak concentration in this investigation and had no detectable norpropoxyphene in plasma. Most of the patients, unlike the normal subjects, experienced considerable sedation after propoxyphene. These results are probably due to increase systemic availability of orally administered propoxyphene in patients with hepatic cirrhosis and possibly to increased receptor response to the drug by these patients. It is concluded that propoxyphene should be administered cautiously and in reduced doses to patients with hepatic dysfunction. 相似文献
66.
Design of waste rock barriers forming safety berms for haul trucks requires knowledge of complex interactions which cannot readily be tested by physical means. An advanced numerical model based on non-smooth multi-domain mechanics is presented together with model calibration using limited full-scale experimental data. Waste rock is represented by spherical particles with rolling resistance, and an ultra-class haul truck is represented by a rigid multibody system interconnected with mechanical joints. The model components are first calibrated and then the calibrated model is used for simulating various collision scenarios with different approach conditions and safety berm geometries. Numerical predictions indicate that the width of the berm is most critical for efficiently stopping a runaway truck. The model can also predict if a certain berm geometry is capable of stopping a runaway truck. Results are summarised in a series of diagrams intended for use as design guidelines by practitioners and engineers. 相似文献
67.
68.
This paper presents an approximate discretization method, named Mixed Euler-ZOH (mE-ZOH), which can be applied to any continuous-time linear system. This method has been explicitly developed to preserve the system sparsity, a property that is particularly important when dealing with the analysis and design of distributed controllers for large-scale systems. In terms of stability preservation as a function of the sampling interval, we show that mE-ZOH outperforms the classical forward Euler (fE) approach, which is the only known discretization method guaranteeing the preservation of sparsity for all possible sampling times. It is then shown that this new discretization method is capable of preserving stability for all sampling times for a wide classes of dynamical systems, including the important class of positive systems. Besides stability, also positivity of the resulting discrete-time system is preserved, contrarily to what happens for the fE approach. A couple of examples are reported to illustrate the main theoretical results of the paper. 相似文献
69.
H Young A Moyes K Horn GR Scott C Patrizio S Sutherland 《Canadian Metallurgical Quarterly》1998,9(11):661-665
BACKGROUND: The ratio of free PSA in total PSA (f/t) has been reported to improve the diagnostic accuracy of prostate cancer in the group with slightly elevated serum PSA values. In Japanese cases, the clinical significance of f/t is still controversial. METHODS: The diagnostic significance of f/t in serum for prostate cancer was evaluated in a cooperative study. A total of 77 cases with prostate cancer and 224 with non-prostate cancer showing less than 20 ng/ml of total PSA were evaluated. RESULTS: Serum total and free PSA values were not affected by storage at 25 degrees C for 2 days. The determination of f/t was useful in the cases with a serum total PSA of 5.1-10 ng/ml; the specificity was 60% with a sensitivity of 90% at an f/t of 0.148. The positive predictive value for diagnosis of prostate cancer also increased to 54% from 34% of that in total PSA alone. In the range of 4.1-10 ng/ml, the cut-off value of f/t was 0.155 for obtaining relatively high specificity; sensitivity was 85% and specificity was 56.5%. CONCLUSIONS: Thus, the determination of f/t was considered to be an effective tool for discriminating the non-prostate cancer cases from those of prostate cancer. 相似文献
70.
Yonggang Zhang Jiaping Li Mohammad Soleimani Francesca Giacomini Heiner Friedrich Roman Truckenmüller Pamela Habibovic 《Advanced functional materials》2021,31(40):2102911
Biodegradable porous calcium phosphate (CaP) ceramics are widely used as synthetic graft substitutes for bone regeneration, owing to their chemical and structural similarity to bone and associated bioactivity in terms of bone-bonding, osteoconductive, and even osteoinductive properties. Nevertheless, the intrinsic brittleness and poor processability of porous CaP ceramics strongly impair their clinical applicability. Herein, a biphasic calcium phosphate (BCP) sponge is developed that consists of a self-supporting network of seamlessly interwoven hydroxyapatite nanowires and β-tricalcium phosphate nanofibers and possesses a highly interconnected porous structure with open cell geometry and ultrahigh porosity. Owing to its unique properties, the ceramic sponge can be easily processed into various shapes and dimensions, such as cylindrical scaffolds and thin, flexible membranes. Moreover, the BCP sponge can be introduced into a bone defect in a compacted or folded state from a syringe and, upon wetting, expand to its original shape, thereby filling the cavity. The nanofibrous sponge gradually degrades in vitro and rapidly mineralizes when immersed in simulated body fluid. Moreover, it adsorbs significantly more proteins than a conventional porous BCP ceramic. Finally, the nanofibrous sponge supports the attachment, proliferation, and osteogenic differentiation of human mesenchymal stromal cells comparable to the conventional porous BCP ceramic. 相似文献