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1.
Context: The administration of pharmabiotics is a promising alternative to antimicrobial drugs for the treatment and/or prevention of female urogenital infections.

Objective: To design pharmabiotic formulations including bioactive ingredients of microbial origin combined with non-microbial substances and then to evaluate the stability of the combinations during freeze-drying and storage.

Materials and methods: Different formulations including Lactobacillus gasseri CRL 1263, Lactobacillus salivarius CRL 1328, salivaricin CRL 1328 (a bacteriocin) and non-microbial compounds (lactose, inulin and ascorbic acid) were assayed, and the ingredients were freeze-dried together or separately. The formulations were stored in gelatin capsules at 4?°C for 360?d.

Results: The viability of lactobacilli was affected to different extents depending on the strains and on the formulations assayed. L. salivarius and ascorbic acid were successfully combined only after the freeze-drying process. Salivaricin activity was not detected in formulations containing L. gasseri. However, when combined with ascorbic acid, lactose, inulin or L. salivarius, the bacteriocin maintained its activity for 360?d. The selected microorganisms proved to be compatible for their inclusion in multi-strain formulations together with lactose, inulin and ascorbic acid. Salivaricin could be included only in a L. salivarius CRL 1328 single-strain formulation together with non-microbial substances.

Conclusions: This study provides new insights into the design of urogenital pharmabiotics combining beneficial lactobacilli, salivaricin CRL 1328 and compounds with different functionalities.  相似文献   
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Telecenters take on a prominent role within the current information and communications technology (ICT) ecosystem in Brazil. They are seen by a great many as a key means to foster the digital inclusion of the older population in the country. This paper draws upon a rapid ethnographic study conducted with 78 older people in a center that teaches computer classes to seniors in Brazil. The results show that providing older people with technological infrastructures is not enough to strengthen their digital inclusion if their basic and non-instrumental needs are not taken into consideration in defining educational activities to be carried out in public centers. Participants’ basic needs when it comes to interacting with ICT, such as coping with accessibility issues, were dynamic, whilst non-instrumental needs, fulfilled by using these technologies, such as interacting with relevant others, remained fairly constant throughout the study. Drawing on the results of the study, strategies for fostering the digital inclusion and well-being of older people in Brazil that go beyond telecenters are suggested.  相似文献   
4.
Sorghum flour was heat treated for producing an instant dispersion ingredient. The precooked sorghum flour was added with ACE-I and DPP-IV inhibitory sorghum peptides (3.0 g peptide 100 g−1). The product was reconstituted in water, and peptide bioaccessibility was evaluated by equilibrium dialysis method after simulated gastrointestinal digestion. Total peptide dialysability of precooked sorghum flour added with sorghum peptides was higher than those obtained for precooked sorghum flour (315.9 ± 14.8 vs. 45.2 ± 5.6 µmol, respectively) (P < 0.05). The ACE-I and DPP-IV-IC50 values of the bioaccessible peptides from the bioactive product were lower than those obtained for precooked sorghum flour ingredient (1.04 ± 0.12 vs. 1.82 ± 0.09 and 0.86 ± 0.02 vs. 2.12 ± 0.08 mg protein mL−1, for ACE-I and DPP-IV, respectively) indicating a higher activity. Precooked sorghum flour was a good vehicle since it did not affect the bioaccessibility of ACE-I and DPP-IV inhibitory peptides provided by sorghum protein hydrolysate.  相似文献   
5.
The effect of pH on colour and iron content (Fe) of peptide fractions obtained from bovine haemoglobin concentrate (BHC) hydrolysates was studied. Four hydrolysates were obtained using three enzymes: Protex‐6‐L (P), Fungal–Protease–Concetrate (FC) and Flavourzyme (F). BHC and its hydrolysates (P, FC, P + F, FC + F) were fractioned at pH 4.5, 7.0 and 9.5. Solubility and Fe from different fractions were measured. Correlations between CIELAB colour parameters and Fe from different fractions were analysed. The colour from different fractions varied from red to yellow (a* and b* positives). Lightness values (L*) ranged from twenty‐four to seventy. FC4.5 and FC + F4.5 fractions were the clearest and yellow (higher L*, b*, h), while BHC9.5 and P + F9.5 fractions had the lowest values of L*, b* and h. There was an inverse linear relationship between b* and L* parameters and Fe from fractions. This relationship could be associated with the pH of extraction. As pH increases Fe significantly increases and lower b* and L* values were obtained.  相似文献   
6.
BACKGROUND: The culture medium for optimal growth of vaginal Lactobacillus salivarius CRL 1328 is different from that for optimal bacteriocin production. To simultaneously obtain high amount of biomass and bacteriocin of this microorganism, the effects of different basal culture media and salts on both responses were evaluated. The study was performed by using a complete factorial experimental design 26, with central points. Sixty‐four different growth media, which resulted from the combinations of two basal culture media and two concentrations of five salts (ammonium citrate, sodium acetate, MgSO4, MnSO4, and K2HPO4) were assayed. RESULTS: Only the addition of MnSO4 to each culture medium significantly stimulated the growth of L. salivarius. The presence of sodium acetate or MgSO4 stimulated the bacteriocin production, while MnSO4 and K2HPO4 exerted an inhibitory effect. However, the simultaneous addition of MnSO4 and sodium acetate to both basal culture media allowed high bacteriocin levels to be reached, attenuating the inhibitory effect of Mn2+. CONCLUSIONS: The application of a complete experimental design contributed to simultaneous optimization of the biomass and bacteriocin production of L. salivarius CRL 1328. The results obtained are potentially applicable to the technological production of probiotic bacteria and antagonistic substance to be included in a probiotic pharmaceutical product. Copyright © 2009 Society of Chemical Industry  相似文献   
7.
Flour blends based on whole corn and rice with two added wild legumes at 15% level of cereal replacement were extruded to produce whole grain snacks. Extrusion temperature was 175 °C, and the moisture content was adjusted to 14%. The extruded products were evaluated for their physical, chemical and nutritional properties. Results showed that the addition of legumes produces a decrease in expansion in rice‐containing samples and an increase in solubility in corn‐containing samples. With only 15% of legume added to cereal, a significant increase in protein content and quality was obtained. An increase in fibre, polyphenol, iron and zinc content was also obtained. Protein digestibility was in the range of 81.8–85.3%. Mineral availability ranged from 6.4 to 16.3% for iron and 10–16.3% for zinc. The performance of each mixture during extrusion and the physical properties of the extruded products were considered to be similar to those expected for snack‐type products and described in the literature.  相似文献   
8.
This work describes the synthesis of the green and black polymorphic forms of the tetrathiafulvalene–chloranil (TTF–CA) charge transfer salt as pure phases, by solvent-assisted mechanochemistry. Both materials were characterized using laboratory and high-resolution X-ray powder diffraction (XRPD), elemental analysis and scanning electron microscopy (SEM). The high-resolution XRPD pattern of the TTF–CA black polymorph was indexed with a triclinic lattice a = 10.756(5) Å, b = 11.057(4) Å, c = 6.614(2) Å, α = 101.36(2)°, β = 93.69(3)°, γ = 89.37(3)°, V = 769.6(5) Å3. The chemical stability of these phases upon heating was investigated using thermogravimetric analysis (TGA), elemental analysis and X-ray powder diffraction (XRPD), indicating that both polymorphs undergo chemical decomposition, and ruling out the transition to an air-stable high temperature polymorph.  相似文献   
9.
Aliphatic [n]‐polyurethanes have recently been synthesized from ω‐isocyanato‐α‐alkanols or, more traditionally, by cationic ring‐opening polymerization of cyclourethanes or by the Bu2Sn(OMe)2‐promoted polycondensation of ω‐hydroxy‐α‐O‐phenylurethane alkanes. For the latter procedures, the conditions employed do not seem to be suitable for highly functionalized monomers. In contrast, the polymerization of ω‐amino‐α‐phenylcarbonate alkanes is expected to occur under milder conditions. ω‐Amino‐α‐phenylcarbonate alkanes have been synthesized from 6‐aminohexanol (1) and 3‐aminopropanol (6). The procedure involves the N‐Boc protection of the amino group, followed by activation of the alcohol. Removal of the N‐Boc affords the corresponding ω‐amino‐1‐O‐phenyloxycarbonyloxyalkane hydrochlorides. Other oligomeric comonomers between 1 and 6 have been prepared. The polymerization of these precursors takes place in the absence of metal catalysts to afford the corresponding linear and regioregular [n]‐polyurethanes. The procedure described is useful for the preparation of stable ω‐amino‐α‐phenylcarbonate alkane derivatives, which possess varied chain lengths between the terminal functions. These monomers yield [n]‐polyurethanes having various structures starting from just two aminoalkanols. The polyurethanes were obtained in high yields, with reasonable molecular weight and polydispersity values, and they were characterized spectroscopically and thermally. These studies reveal constitutionally uniform structures that are free of carbonate or urea linkages. Copyright © 2010 Society of Chemical Industry  相似文献   
10.
A characterization study of the main olive oil cultivars of southwest Spain (Picual, Arbequina, and Verdial) has been performed in order to establish logistic regression models. Several quality characteristics (free acidity, peroxide value, K232, K270, oxidative stability index) and chemical data (fatty acids, sterols, erythrodiol–uvaol composition) were measured. Logit regressions were used to evaluate the correlation of the parameters and to create models that allow saving costs on identifying oils as Arbequina, Picual, or Verdial type. Multiple logit regression models were developed: one for Arbequina, three models for Picual, and two models for Verdial cultivar, allowing in this way to minimize the cost for classifying oil samples. Practical application: The olive oil marketing is increasingly focused on the chemical differentiation and characterization of the product because the chemical composition of these virgin oils is responsible for their valuable sensory and nutritional properties. Here we present a characterization study (quality characteristics and chemical data) from the main olive oil cultivars of southwest Spain, Picual, Arbequina, and Verdial, as a first step for the traceability of these three types of monocultivar virgin olive oils. The results may be used as a training to create models for other olive oil cultivars.  相似文献   
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