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91.
92.
Bread is a most important food product and source of selenium in Ukraine. However, low content of selenium in wheat flour from north and northwest regions of Ukraine does not ensure the recommended consumption of selenium. Daily intake of selenium by the population of North Ukraine is below recommended allowance. The aim of this research was to study the production of the dietary rolls with selenium-enriched yeast for the population of North Ukraine. The study showed that to obtain bakery yeast of good quality, concentration of sodium hydroselenite in the medium for yeast cultivation should be in the range from 2 to 5 μg Se/ml. Under these concentrations of selenium in medium, specific growth rate and biomass yield as well as bakery properties of the yeast Saccharomyces cerevisiae did not differ from the parameters of yeast, grown in the medium without selenium. Maturation of the selenium-enriched yeast improved their bakery properties. The 100 g wheat roll prepared with selenium-enriched yeast contained 50 μg Se (25% of the recommended daily allowance) in the form of selenomethionine, which is the best form of selenium for human consumption. These rolls can be used as a dietary product to reach recommended daily consumption of selenium by the population of North Ukraine and Chernobyl region.  相似文献   
93.
94.
Oligomeric azodinitrile compounds with epoxy groups were synthesized by interaction between 4,4'-azo-bis-(4-cyanopentanoic) acid and diglycydyl ethers of diphenylpropane, ethylene glycol and resorcine in the presence of benzyltriethylammmonium chloride as the catalyst. Effects of temperature, reaction medium, initial components ratio and catalyst concentration on oligomer yields have been studied. Styrene polymerization is an example demonstrating the possibility of using such compounds for obtaining oligomers with epoxy end groups. Electronic Publication  相似文献   
95.
In order to compare the adsorptive properties of nanoporous zeolites containing extraframework cations of different nature, we have studied the interaction of H2 with Na-A, Ca-A, and Co,Na-A zeolites. Low temperature Fourier transform infrared (FT-IR) spectroscopy was used for the investigation, as this technique is highly sensitive and responsive to the nature of the gas/surface interaction and can in addition allow for the estimation of the adsorption enthalpy. In all cases the spectra of adsorbed H2 have complex structure due to ortho/para splitting as well as to surface structural disorder. Na+ and divalent Ca2+ were found to induce almost similar perturbation on H2 molecule, resulting in the shift of the H-H vibrational frequency of −86 cm−1 and −76 cm−1 respectively (as compared to the Raman frequency of gaseous H2). The enthalpy of adsorption, estimated by the Variable Temperature Infrared (VTIR) method, is −13 ± 1 kJ mol−1 for the strongest adsorptive sites in Na-A and Ca-A samples. In the case of Co,Na-A the shift of the H-H frequency due to the formation of H2?Co2+ complexes is larger (ca. −180 cm−1) suggesting that the interaction can involve some, although small, chemical contribution.  相似文献   
96.
The k-MST is a well known NP-hard problem and several approximation algorithms exist to solve this problem with a guaranteed performance bound. A closely related problem, called the bottleneck k-MST (BMST(k)) can however be solved in O(mlogn) time on graph with n nodes and m edges. We propose two algorithms to solve BMST(k), one of complexity O(m+nlogn) and the other of O(m) time. We also consider a generalization of BMST(k) which subsumes many bottleneck problems studied in the literature and show that this generalized problem can also be solved in O(m) time.  相似文献   
97.
98.
Metallography, DTA, x-ray, and electron-probe microanalysis methods have been applied to alloys with four compositions in the cast and annealed states. A phase diagram has been constructed for the entire concentration range on the basis of these data together with published ones. The diagram is of peritectic type, and the peritectic temperature is 1500°C. The mutual solubilities of the components at that temperature are 13.3 at.% osmium in nickel and 13 at. % nickel in osmium. The solubility of osmium in nickel falls to 9.2 at. % when the temperature is reduced to 1200°C.  相似文献   
99.
Purpose: To evaluate the antifungal activity of amphotericin B (AmB) in a mouse model of systemic candidiasis following administration of a novel oral AmB formulation (iCo-010) that has been pre-exposed to tropical temperatures.

Methods: Amphotericin B (AmB) was prepared as a 5?mg/mL dispersion in a mixture of Peceol, Gelucire 44/14 and VitE-TPGS 2,3 (iCo-010). The formulation was protected from light and incubated in a sealed container at 43?°C for 60 days. Mice infected with Candida albicans were treated with either iCo-010 formulation pre-incubated at 43?°C for 60 days or freshly prepared iCo-010 formulation at doses of 5, 10 and 20?mg/kg once daily for five consecutive days. Single intravenous 5?mg/kg dose of AmBisome® was used as a positive control group. Seven days following the last dose, the kidney, liver, spleen, lung, heart and brain were removed and the number of colony forming units (CFUs) was determined as a measure of tissue fungal load. In addition, the concentration of AmB within each tissue was determined using high performance liquid chromatography (HPLC).

Results: There were no significant differences in the reduction of CFUs and the concentration of AmB recovered in all organs at all iCo-010 doses tested between the freshly prepared iCo-010 formulation compared to the formulation that was incubated at 43?°C for 60 days.

Conclusions: A novel oral AmB formulation, iCo-010, incubated at 43?°C for 60 days to simulate the exposure of the formulation to tropical temperatures remained highly effective against murine systemic candidiasis.  相似文献   
100.
ABSTRACT

Purpose: The purpose of this study was to assess the lipid lowering and plasma cholesteryl ester transfer protein (CETP) activity following administration of simvastatin to rabbits fed a high fat/cholesterol diet. Methods: Male New Zealand white rabbits were housed in individual cages and fed a standard diet for 7 days. After 7 days, animals were fed 10 g of a regular chow diet plus 100 g of the same diet supplemented with 0.5% (w/v) cholesterol and 14.0% (w/v) coconut oil for 28 days. Following 28 days on this diet, the animals were randomized based on plasma cholesterol and triglyceride levels, into a group of control animals and a group (n = 6) of animals fed 100 g of cholesterol/coconut diet plus 10 g regular chow diet containing simvastatin (3 mg/kg/day) for an additional 28 days. Blood samples were taken from the marginal ear vein prior to and 28 days after the initiation of drug treatment. Plasma was harvested and stored at 4°C prior to lipid analysis. Plasma total cholesterol and triglyceride levels were quantified using enzymatic kits. HDL (high-density lipoproteins) cholesterol levels were determined using the dextran sulfate-Mg2+ precipitation method. ApoB cholesterol levels were determined by subtracting total cholesterol from HDL cholesterol. Cholesteryl ester transfer protein (CETP) activity was determined by standard assay methods. Results: We observed that simvastatin significantly reduced total plasma cholesterol, triglyceride, and apoB cholesterol compared to non-treated controls. Simvastatin treatment did not alter serum CETP activity compared to non-treated controls. Conclusions: These findings suggest that decreasing plasma lipid levels by treatment with simvastatin is not due to changes in serum CETP activity in rabbits fed a high fat/cholesterol diet.  相似文献   
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