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31.
The characteristics of a concrete mix are purely dependent on the hydration of cement that is carried forward by using the water quality used in the mix. Several researchers have focused on incorporating pozzolanic or nanomaterials to improve the hydration mechanisms and impart high strength to concrete. A new technology has been introduced to improve the properties of concrete by magnetic-field-treated water (MFTW). Due to magnetization, water particles become charged and the molecules inside the water cluster decrease from 13 to 5 or 6, which eventually decreases the hardness of water, thus improving the strength of concrete when compared to the use of normal water (NW). In advanced construction techniques and practices, the application of Magnetic Water (MW) plays an important role in boosting physicochemical properties. This research work focused on evaluating the standards of water quality through physiochemical analysis, such as Electrical Conductivity (EC), Viscosity, pH, and Total Dissolved Solids (TDS) with the MW at different exposure periods (60 min (MW60), 45 min (MW45), 30 min (MW30), 15 min (MW15), and instant exposure (MWI)). Experiments were carried out to evaluate the fresh, hardened, and microstructural behavior of concrete made with magnetic water (MW) using a permanent magnet of PERMAG (N407) under a field intensity of 0.9 Tesla. In addition, optical properties such as X-ray Diffraction (XRD) and Ultraviolet (UV) absorption were considered for the MW60 mix to ensure water magnetization. Characterization methods such as Fourier Transform Infrared Spectroscopy (FT-IR), Thermogravimetric Analysis (TGA), and Scanning Electron Microscopy (SEM) were employed for NWC and MWC to quantify the hydrated products. From the results, it was observed that the magnetic effect on water characteristics showed significant improvement in the concrete properties with the increase in exposure duration. There were increments of 25.6% and 24.1% in workability and compressive strength, respectively, for the MW60 mix compared to normal water concrete (NWC).  相似文献   
32.

Purpose

To fabricate microneedle arrays directly off a photomask using a simple photolithographical approach and evaluate their potential for delivering collagen.

Methods

A simple photolithographical approach was developed by using photomask consisting of embedded micro-lenses that govern microneedle geometry in a mould free process. Microneedle length was controlled by use of simple glass scaffolds as well as addition of backing layer. The fabricated arrays were tested for their mechanical properties by using a force gauge as well as insertion into human skin with trypan blue staining. Microneedle arrays were then evaluated for the delivery of fluorescent collagen, which was evaluated using a confocal laser scanning microscope.

Results

Microneedles with sharp tips ranging between 41.5?±?8.4 μm and 71.6?±?13.7 μm as well as of two different lengths of 1336?±?193 μm and 957?±?171 μm were fabricated by using the photomasks. The microneedles were robust and resisted fracture forces up to 25 N. They were also shown to penetrate cadaver human skin samples with ease; especially microneedle arrays with shorter length of 957 μm penetrated up to 72% of needles. The needles were shown to enhance permeation of collagen through cadaver rat skin, as compared to passive diffusion of collagen.

Conclusions

A simple and mould free approach of fabricating polymeric microneedle array is proposed. The fabricated microneedle arrays enhance collagen permeation through skin.  相似文献   
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A novel series of aceclofenac hybridised with 1,2,4-triazolo-[3,4-b]-1,3,4-thiadiazoles were designed using molecular hybridization approach and synthesised 6aj. The structural integrity was confirmed by analytical methods. The hybrid molecules were subjected to in vitro cytotoxic studies against four human cancer cell lines PA‐1, OAW‐42, T47-D and MCF‐7 by MTT assay method. The results indicate that the hybrid molecules bearing halogen on phenyl ring in 6th position of triazolo-thiadiazole exhibited significant cytotoxic activity. The test compounds were also screened for antifungal activity against two strains.  相似文献   
35.
A series of pyrrolidine‐, piperidine‐, and imidazoline‐based dithiocarbamate CTAs have been synthesized and utilized to control the polymerization of vinyl monomers. The controlling ability of the CTAs depends on the presence of both activating and re‐initiating groups and the monomer used. Pyrrolidine‐ and piperidine‐based CTAs proved reasonably good for controlling vinyl acetate polymerizations. The living nature of the vinyl acetate polymerizations was studied by kinetics and chain extension reactions. Interestingly the vinyl acetate polymers synthesized using these pyrrolidine and piperidine based CTAs were almost colorless when precipitated and, therefore, were interesting considering the industrial applications of these polymers.

  相似文献   

36.
A series of novel 3-(4-chlorophenyl)-2-(3-substituted propyl) quinazolin-4-(3H)-ones have been synthesized and tested for their in vivo H1-antihistaminic activity on conscious guinea pigs. All the test compounds have protected the animals from histamine induced bronchospasm significantly. Compound 3-(4-chlorophenyl)-2-(3-(4-methylpiperazin-1-yl) propylthio) quinazolin-4(3H)-one (PC5) emerged as the most active compound (77.53% protection) of the series when compared to the reference standard chlorpheniramine maleate (70.09% protection). Compound PC5 shows negligible sedation (6.16%) compared to chlorpheniramine maleate (29.58%). Therefore, compound PC5 can serve as the lead molecule for further development into a new class of H1-antihistaminic agents.  相似文献   
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38.
Background Tuberculosis (TB) and cancer can coexist in some patients especially from low- and middle-income countries. Impact of active TB on treatment decisions in cancer is less well studied. Methods A retrospective case record review of all cases of cancer diagnosed and or treated between January 2012 and December 2019 who were also diagnosed to have active TB (pulmonary or extrapulmonary) was done. Results Any delay or change in standard treatment of cancer because of active TB or its treatment was noted. Among a total of 32,509 cancer cases, 56 (0.17%) patients were diagnosed to have active TB. Twenty six patients (46%) had delay in starting treatment or delay during cancer treatment. Six (11%) patients were changed from curative treatment option to palliative intent (either best supportive care or palliative Radiation) or no further treatment. Three (5%) patients required change from one type of curative treatment modality to another curative option. Conclusion Eleven percent of patients had to be changed from curative intent to palliative treatment or no further treatment, TB being either the direct or indirect cause in all of them. A nationwide data registry of cancer patients with TB, involving multiple centers, should be considered so that specific problems in this context can be identified and addressed in larger details.  相似文献   
39.
Predictive scientific principles and methods to assess in vivo performance of pharmaceutical dosage forms based on in vitro studies are important in order to minimize costly animal and human experiments during drug development. Because of issues related to poor solubility and low permeability of newer drug candidates, there has in recent years been a special focus on in vitro-in vivo correlation (IV-IVC) of drug products, particularly those used orally. Various physicochemical, biopharmaceutical, and physiological factors that need to be considered in successful IV-IVC of immediate-release oral dosage forms are reviewed in this article. The physicochemical factors include drug solubility in water and physiologically relevant aqueous media, pK(a) and drug ionization characteristics, salt formation, drug diffusion-layer pH, particle size, polymorphism of drug substance, and so forth. The biopharmaceutical factors that need to be considered include effects of drug ionization, partition coefficient, polar surface area, etc., on drug permeability, and some of the physiological factors are gastrointestinal (GI) content, GI pH, GI transit time, etc. Various in silico, in vitro, and in vivo methods of estimating drug permeability and absorption are discussed. Additionally, how IV-IVC may be applied to immediate-release oral dosage form design are presented.  相似文献   
40.
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