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131.
The objective of this study was to develop an effective omeprazole buccal adhesive tablet with excellent bioadhesive force and good drug stability in human saliva. The omeprazole buccal adhesive tablets were prepared with various bioadhesive polymers, alkali materials, and croscarmellose sodium. Their physicochemical properties, such as bioadhesive force and drug stability in human saliva, were investigated. The release and bioavailability of omeprazole delivered by the buccal adhesive tablets were studied. As bioadhesive additives for the omeprazole tablet, a mixture of sodium alginate and hydroxypropylmethylcellulose (HPMC) was selected. The omeprazole tablets prepared with bioadhesive polymers alone had bioadhesive forces suitable for a buccal adhesive tablet, but the stability of omeprazole in human saliva was not satisfactory. Among alkali materials, only magnesium oxide could be an alkali stabilizer for omeprazole buccal adhesive tablets due to its strong waterproofing effect. Croscarmellose sodium enhanced the release of omeprazole from the tablets; however, it decreased the bioadhesive forces and stability of omeprazole tablets in human saliva. The tablet composed of omeprazole/sodium alginate/HPMC/magnesium oxide/croscarmellose sodium (20/24/6/50/10 mg) could be attached on the human cheek without disintegration, and it enhanced the stability of omeprazole in human saliva for at least 4 h and gave fast release of omeprazole. The plasma concentration of omeprazole in hamsters increased to a maximum of 370 ng/ml at 45 min after buccal administration and continuously maintained a high level of 146-366 ng/ml until 6 h. The buccal bioavailability of omeprazole in hamsters was 13.7% ± 3.2%. These results demonstrate that the omeprazole buccal adhesive tablet would be useful for delivery of an omeprazole that degrades very rapidly in acidic aqueous medium and undergoes hepatic first-pass metabolism after oral administration.  相似文献   
132.
LC-MS法测定钙片中酪蛋白磷酸肽含量   总被引:2,自引:0,他引:2  
用液相色谱-质谱联用法,以选择离子模式(SIM)检测钙片中酪蛋白磷酸肽(CPP)含量。结果表明,该法前处理简便,专属性好,灵敏度高,检出限为1μg/ml,在1~100μg/ml范围内线性回归方程为y=3074.6x+684.6,R2=0.999,回收率为96%~104%,可用于测定钙片中CPP的含量,也可用于其它钙强化剂中添加CPP的检测。  相似文献   
133.
张琼  张向农  涂秀华 《金属学报》2005,10(9):1069-1072
目的: 评价麝香心痛宁片治疗冠心病心绞痛(气滞血瘀证) 的临床疗效和安全性。方法: 206 例受试者采用随机、双盲双模拟、阳性药平行对照、多中心临床研究方法(麝香心痛宁组服用麝香心痛宁片, 对照组服用心可舒片), 其中麝香心痛宁组103例、对照组103 例。结果: 麝香心痛宁组心绞痛显效率为48.54%, 总有效率为90.29%;对中医症状的总有效率91.26%, 优于心可舒组(P <0.01);麝香心痛宁组试验后心绞痛平均发作次数、中医症状平均积分均有明显减少(P <0.01), 低于心可舒组(P<0.05);麝香心痛宁组胸痛、胸闷、气短、心悸症状与心可舒组比较有显著减少(P <0.05);麝香心痛宁组试验后血液流变学主要指标均有明显改善(P<0.05)。结论: 麝香心痛宁片治疗冠心病心绞痛(气滞血瘀证) 疗效确切, 临床试验期间无不良反应发生。  相似文献   
134.
The “quality by design” concept in pharmaceutical formulation development requires the establishment of a science-based rationale and design space. In this article, we integrate thin-plate spline (TPS) interpolation, Kohonen’s self-organizing map (SOM) and a Bayesian network (BN) to visualize the latent structure underlying causal factors and pharmaceutical responses. As a model pharmaceutical product, theophylline tablets were prepared using a standard formulation. We measured the tensile strength and disintegration time as response variables and the compressibility, cohesion and dispersibility of the pretableting blend as latent variables. We predicted these variables quantitatively using nonlinear TPS, generated a large amount of data on pretableting blends and tablets and clustered these data into several clusters using a SOM. Our results show that we are able to predict the experimental values of the latent and response variables with a high degree of accuracy and are able to classify the tablet data into several distinct clusters. In addition, to visualize the latent structure between the causal and latent factors and the response variables, we applied a BN method to the SOM clustering results. We found that despite having inserted latent variables between the causal factors and response variables, their relation is equivalent to the results for the SOM clustering, and thus we are able to explain the underlying latent structure. Consequently, this technique provides a better understanding of the relationships between causal factors and pharmaceutical responses in theophylline tablet formulation.  相似文献   
135.
Handedness is a certain kind of laterality, namely the preference of humans for a certain hand (the dominant hand). Reliable handedness tests are needed in various contexts, for example, to avoid a wrong writing education of children. In this article, we propose a new approach for a gradual rating of hand proficiency which consists of three subtests and is suited for preschool children. We demonstrate the benefits of using a graphics tablet for handedness tests, investigate the advantages of the three subtests and their combination, and outline the possibility of interpreting the gradual output of a classifier. The classification is based on ensembles of support vector machines that are trained with sample data. Input of these classifiers are attributes that reflect various aspects of hand motor skills. The most relevant input attributes of the classifiers are selected from a large set of possible attributes with a ranking technique based on the Gini index. We evaluate this approach using a data set with data gathered from 53 preschool children aged between five and six and a half (45 with certain and known handedness, 8 with uncertain or ambiguous handedness).  相似文献   
136.
The purpose of this study was to describe the raw material variability that influenced the in-vitro dissolution behavior of high drug-load sustained-release matrix tablet and to ensure the consistent quality of the final product. The Panax notoginseng saponins (PNS) – hydroxypropyl methylcellulose – anhydrous lactose – magnesium stearate (57:20:23:0.5%, w/w) was used as the model formulation. PNS extract powders with lot-to-lot and source-to-source differences were collected to cover the common cause variations and their physicochemical properties were characterized by the chromatographic fingerprints and the SeDeM expert system. It was found that the release behavior of active pharmaceutical ingredients (APIs) in PNS from different batches exhibited considerable variations. Latent variable modeling results demonstrated that the physical properties of raw materials played major roles in predicting the drug dissolution. PNS extracts with high specific surface area, the width of particle size distribution and hygroscopicity or low moisture content led to an increase in drug release. In order to perform efficient pass/fail judgments for incoming new materials, multivariate specifications of critical material attributes (CMAs) were established and the multivariate design space in line with the quality by design (QbD) principles was explored to achieve the release target.  相似文献   
137.
The aim of this study was to understand to what extent people can read e‐paper devices under various conditions of ambient illuminance that can occur indoors. In this study, 110 young to elderly subjects participated in an experiment to evaluate the effects of 14 different levels of ambient lighting on their reading from three different electronic devises and paper text. The participants were asked to undergo a timed read task and then to evaluate the readability of two eReader devices (a regular electronic display and one with a front light) in comparison with a backlit liquid crystal device and conventional paper text. The results indicated that backlit and front lit devices are easier to read at less than 200 lx and the reflective device is easier to read at levels above 500 lx.  相似文献   
138.
This study was intended to design an orally disintegrating tablet (ODT) formulation that can mask the extremely bitter and metallic taste of phencynonate HCl by novel ion-exchange resins. The drug–resin complexes (DRCs) were prepared and characterized by scanning electron microscopy, X-ray powder diffraction and differential scanning calorimetry. In vitro properties (dissolution, wetting time and disintegration time) and in vivo behavior (disintegration time and taste-masking effect) in healthy volunteers of the prepared ODTs were also investigated. The drug was changed from the crystal structure to the amorphous form in the DRC. Compared with commercial tablets, the in vitro and in vivo disintegration of optimized DRC-loaded ODTs with a drug-resin ratio of 1:1 was greatly improved and better palatability with a low bitterness index (0.33) was obtained. The current DRC-loaded ODT could promise a good way to mask the unpleasant taste of certain drugs and accordingly improve the patient compliance.  相似文献   
139.
Objective: While previous research has demonstrated roller compaction operating parameters strongly influence the properties of the final product, a greater emphasis might be placed on the raw material attributes of the formulation. There were two main objectives to this study. First, to assess the effects of different process variables on the properties of the obtained ribbons and downstream granules produced from the rolled compacted ribbons. Second, was to establish if models obtained with formulations of one active pharmaceutical ingredient (API) could predict the properties of similar formulations in terms of the excipients used, but with a different API.

Materials and methods: Tolmetin and acetaminophen, chosen for their different compaction properties, were roller compacted on Fitzpatrick roller compactor using the same formulation. Models created using tolmetin and tested using acetaminophen. The physical properties of the blends, ribbon, granule and tablet were characterized. Multivariate analysis using partial least squares was used to analyze all data.

Results: Multivariate models showed that the operating parameters and raw material attributes were essential in the prediction of ribbon porosity and post-milled particle size. The post compacted ribbon and granule attributes also significantly contributed to the prediction of the tablet tensile strength.

Conclusions: Models derived using tolmetin could reasonably predict the ribbon porosity of a second API. After further processing, the post-milled ribbon and granules properties, rather than the physical attributes of the formulation were needed to predict downstream tablet properties. An understanding of the percolation threshold of the formulation significantly improved the predictive ability of the models.  相似文献   

140.
选用营养互补的几种蔬菜。通过制浆、浓缩、冻干、粉碎、调配、成型等工艺。制备了一种天然、营养、健康、方便、休闲的复合蔬菜咀嚼片。  相似文献   
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