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1.
A combined-modality treatment program consisting of botulinum toxin injection (Botox) and voice therapy was used to treat 17 subjects diagnosed with adductor spasmodic dysphonia (ADD SD). Ten subjects with ADD SD served as the control and were given Botox only. Voice therapy after Botox injection was directed toward reducing the hyperfunctional vocal behaviors, primarily glottal overpressure at voice onset and anterior-posterior squeezing. The results indicated that subjects who underwent combined-modality treatment maintained significantly higher mean airflow rates for significantly longer periods. Moreover, there was a carryover effect in these patients when they received Botox only. Adductor spasmodic dysphonia is treated most effectively when intrinsic laryngeal muscle spasms are reduced or eliminated by Botox injection and extrinsic hyperfunctional vocal behaviors are treated with voice therapy  相似文献   
2.
Application of stir bar sorptive extraction for wine analysis   总被引:4,自引:0,他引:4  
Stir bar sorptive extraction (SBSE) coupled with gas chromatography/mass spectrometry (GC/MS) was used to analyse wine samples for three applications: flavour and compositional analysis; 2,4,6-trichloroanisole (TCA), a common off-aroma in wine; and agrochemicals. SBSE was found to be orders of magnitude more sensitive than modern conventional methodology, allowing for lower detection and quantitation levels, and improved confirmation of identity; SBSE often gave better signal to noise in scan mode than other methods in selective ion monitoring (SIM) mode. With the help of their characteristic mass spectra all agrochemicals could be identified unambiguously at concentrations of 10 microg L(-1) in wine and a further 100 constituents were detected in a Cabernet Sauvignon sample. Thus it is now possible to analyse complex samples such as wine by scan mode, with better confirmation of identity, and without sacrificing sensitivity, where previously SIM methodology had to be used.  相似文献   
3.
Assessment of function in patients with spasmodic dysphonia is necessary to confirm diagnosis, plan therapy, predict response, and assess effectiveness of treatment. This task is difficult because symptom severity fluctuates, the test environment is artificial, and the objective parameters used to measure vocal function may not adequately reflect the handicap experienced by the patient. Available methods for assessing these patients are reviewed and the utility of each considered, particularly in managing patients with botulinum toxin therapy. Assessment should include a battery of tests, including subjective perceptual ratings and direct physical measurements.  相似文献   
4.
Bonnart R  Volk GM 《Cryo letters》2010,31(3):200-205
Arabidopsis thaliana shoot tips were successfully cryopreserved using encapsulation-dehydration cryopreservation methods. Between one and seven shoot tips were encapsulated within 4 mm calcium-alginate beads. Beads were formed in the presence of 2 M glycerol + 0.4 M sucrose. The time required to make 10 beads, each containing five shoot tips (4 min), was less than the time required to make 50 beads containing one shoot tip (12 min). Shoot tip regrowth after cryoexposure was between 60 and 68%, with one to seven shoot tips per bead. Using five Arabidopsis shoot tips per bead, alginate beads were formed either in the presence of 2 M glycerol + 0.4 M sucrose or 0.5 M sucrose. Beads formed in the presence of glycerol were immediately air-dried to moisture contents between 0.21 to 0.26 g H2O/g FW (0.27 to 0.38 g H2O/g DW). Alginate beads formed in 0.5 M sucrose were incubated in solutions of 0.5, 0.75, and 1 M sucrose for one day each prior to air-dehydration, achieving moisture contents of 0.19 to 0.21 g H2O/g FW (0.23 to 0.27 g H2O/g DW). Shoot tip regrowth after cryoexposure was between 42 and 65%, with no significant differences among treatments. We successfully reduced the amount of time needed for shoot tip processing for Arabidopsis by encapsulating five shoot tips per alginate bead and by using a glycerol-encapsulation method, without lowering shoot tip regrowth levels after cryopreservation.  相似文献   
5.
The USDA-ARS National Plant Germplasm System (NPGS) maintains more than 200 Allium sativum (garlic) accessions at the Western Regional Plant Introduction Station in Pullman, WA. All accessions must be grown out in the field annually since garlic plants from these accessions do not reliably produce seeds and bulbs do not store well. Shoot tips excised from garlic cloves can be successfully cryopreserved using either Plant Vitrification Solution 2 (PVS2; 15 percent v/v DMSO, 15 percent v/v ethylene glycol, 30 percent v/w glycerol, 0.4 M sucrose) or Plant Vitrification Solution 3 (PVS3; 50 percent v/w sucrose, 50 percent v/w glycerol). We compared regrowth of shoot tips representing diverse garlic germplasm after exposure to either PVS2 or PVS3 during the cryopreservation procedure. At the USDA-ARS National Center for Genetic Resources Preservation, a component of the NPGS, we consider accessions successfully preserved if a minimum of 40 percent of explants exhibit regrowth after liquid nitrogen exposure and at least 60 viable shoot tips remain in long-term storage. Ten of twelve diverse garlic accessions were successfully cryopreserved using either PVS2 or PVS3 as cryoprotectants. Five genotypes had the best post liquid nitrogen regrowth after exposure to PVS2, four genotypes had the best regrowth after exposure to PVS3, and three genotypes performed equally well using either cryoprotectant solution. This project is part of an ongoing program to cryopreserve accessions of NPGS clonal crop collections.  相似文献   
6.
7.
Our main result shows that certain generalized convex functions on a real interval possess a unique best approximation from the family of piecewise polynomial functions of fixed degree with varying knots. This result was anticipated by Kioustelidis in [11]; however the proof given there is nonconstructive and uses topological degree as the primary tool, in a fashion similar to the proof the comparable result for the case in [5]. By contrast, the proof given here proceeds by demonstrating the global convergence of an algorithm to calculate a best approximation over the domain of all possible knot vectors. The proof uses the contraction mapping theorem to simultaneously establish convergence and uniqueness. This algorithm was suggested by Kioustelidis [10]. In addition, an asymptotic uniqueness result and a nonuniqueness result are indicated, which analogize known results in the case.

  相似文献   

8.
The adsorption kinetics of anionic polyacrylamide flocculant onto kaolinite clay are examined as a function of flocculant dosage and pH. Special attention has been given to the flocculation effect during the adsorption process and the resulting inhibition of further adsorption. At pH 8.5 the adsorption capacity of anionic polyacrylamide on kaolinite is low while at pH 4.5, the adsorption capacity increases. Flocculant adsorption has been shown to be related to the amount of available surface area, pH, flocculant dosage, and the resulting floc strength, which controls the rate of new surface area exposure and hence the continuation of further adsorption. At both pH 4.5 and pH 8.5, complete adsorption is achieved at low flocculant dosages and adsorption equilibrium is achieved at high flocculant dosages after 1 day. In contrast, at intermediate flocculant dosages adsorption equilibrium is not reached over a 7-day period, due to a continuously increasing surface area.  相似文献   
9.
1,4,7-Tris(tert-butoxycarbonylmethyl)-1,4,7,10-tetraazacyclododecane is widely used as an intermediate in the preparation of medically important DO3A and DOTA metal chelators. Despite its commercial availability and importance, the literature describing the preparation and properties of the free base is limited and sometimes unclear. We present herein an efficient synthesis of the hydrobromide salt of 1,4,7-tris(tert-butoxycarbonylmethyl)-1,4,7,10-tetraazacyclododecane, characterize this compound spectroscopically and by X-ray crystallographic analysis, describe its simple conversion to the corresponding free base, characterize this compound spectroscopically and by X-ray crystallographic analysis, and make observations on the reactivity of this interesting and useful compound.  相似文献   
10.
The unsymmetrical, optically active ligands 1,2-C(6)H(4)(PPh(2))((R,R)-2,5-dimethylphospholanyl) and the new 1,1'-Fe(C(5)H(4))(2)(PPh(2))((R,R)-2,5-dimethylphospholanyl) form complexes of the type [PtCl(2)(diphos)] and [Rh(diphos)(diene)][BF(4)]. The crystal structure of reveals that only one quadrant is blocked. Asymmetric hydrogenation of acrylic esters and enamides using and as catalysts show that the phenylene-backboned diphosphine gives a more efficient catalyst in terms of asymmetric induction than the more flexible ferrocene-backboned diphosphine. The best results, which were obtained with and enamide substrates, exceeded those obtained with Duphos catalysts. The rate of hydrogenation of the enamides with was 10 times faster than with [Rh(Duphos)(diene)][BF(4)]. A quadrant diagram can be used to predict the configuration of the major product, provided it is assumed to be derived from the less sterically congested intermediate.  相似文献   
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