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111.
A method for studying the effect of some organic compounds, which are neither soluble in water nor to be made into soluble salts in water, on DNA has been investigated by a series of experiments. The solubility experiments have shown that dimethyl sulphoxide (DMSO) and its aqueous solution are excellent solvents for the hydrophobic multicycles compounds with nitrogen atoms. The data of UV (298 K), CD (298 K), ~(31)P-NMR (323 K) spectra and molar enthalpy changes (298 K) for the effect of DMSO on DNA have not shown that DMSO has an effect on DNA when the pH of solution is equal to 7.0 and its concentration is less than 0.15 mol·L~(-1). This has further proved it is safe when DMSO is used as a carrier of medicinal compounds and enters into human bodies. Under the fixed experimental conditions, no differences were found out from the results of viscous tests (298 K) and UV spectra (298 K) for the effect of harmine hydrochloride on DNA in the presence and absence of DMSO even if the concentration of DMSO reached 0.5 mol·L~(-1). It has indicated that the existence of DMSO in aqueous solutions doesn't disturb the effect of compounds on DNA. The data of UV (298 K), CD(298 K), ~(31)P-NMR (323 K) spectra and molar enthalpy changes (298 K) for the effect of some multicycles compounds with nitrogen atoms on DNA in aqueous solutions of DMSO have also given a clear explanation to the intercalation bindings of these organic compounds to DNA, and a method to study the effect of these compounds on DNA can be developed from these experiments. By analying all the data for the effect of the above compounds on DNA, both the mechanism of interaction between the compounds and DNA and the relationship between the rule of intercalation binding of a series of compounds with same multicycles structures to DNA and their microstructures have been discussed. Since the two multicycles compounds with nitrogen atoms including harmine have high bioactivity, the further experiments inside animal bodies and clinical trial on patients as anticancer drugs should be carried out.  相似文献   
112.
目的观察养血消风法治疗慢性荨麻疹的临床疗效及不良反应。方法 90例患者随机分为3组,每组30例,西药组予口服氯雷他定,中药组口服+外洗四物消风饮,中西药组则联合中药及西药进行治疗。观察3组患者皮疹消退及1年内复发的情况及不良反应。结果西药组痊愈8例,有效15例,无效7例,有效率76.7%;中药组痊愈9例,有效15例,无效6例,有效率80%;中西药组痊愈14例,有效14例,无效2例,有效率93.3%。中西药组与其他两组比较,差异有统计学意义(P0.05)。结论养血消风法结合西药治疗慢性荨麻疹可获得良好疗效,复发率低,且不良反应少,值得临床推广应用。  相似文献   
113.
The dried roots of Inula helenium L. (IH) and Inula racemosa Hook f. (IR) are used commonly as folk medicine as ‘tumuxiang’ (TMX). The mixing and sharing of IH and IR in clinical use is a universal phenomenon. Modern pharmacological studies confirmed that IH and IR display anti‐inflammatory activities. However, the difference in anti‐inflammatory pharmacodynamic substances between these two herbs is still unknown. In the present study, the fingerprints of 18 IH and nine IR samples were established using UPLC/QTOF‐MSE. A dimethylbenzene‐induced mouse ear vasodilation model was applied in evaluating the anti‐inflammatory properties of all 27 samples. Then, the spectrum–efficacy model between chemical characteristic peaks and anti‐inflammatory activities was investigated using principal component regression and partial least squares. Finally, the combination of UNIFI Scientific Information System with a library search of traditional Chinese medicines was employed to automatically characterize the peaks. UNIFI identified a total of 80 chemical components. Among the components, the 53 characteristic peaks showed correlation with anti‐inflammatory activities, pointing to phenolic and organic acids as primary anti‐inflammatory ingredients of TMX. This approach can efficiently and intelligently facilitate the identification of bioactive components from traditional Chinese medicine.  相似文献   
114.
将已研制的场效应管(FET)型青霉素传感器应用于工厂和研究所发酵样液的青霉素效价测定。通过与现行的碘量法和比色法进行对比,证明FET型青霉素传感器能够代替碘量法与比色法,是一个简单、快速的青霉素效价检测法。  相似文献   
115.
<正>A membrane composed of an alginate(ALG) layer and a chitosan(CHS) layer with sustained antimicrobial efficacy was prepared.Ciprofloxacin HC1(CIP) was incorporated into the ALG layer.Morphological feature of the composite membrane was analyzed by scanning electron microscopy(SEM).Water uptake capacity,in vitro drug release,and in vitro antimicrobial activity were evaluated.The composite membrane exhibited perfect binding characteristic between the two layers.The water uptake capacity of all the membranes was above 800%.The CIP could release from the composite membranes for 48 h.The membrane could control the bacterial growth persistently.The results suggested that this CHS/ALG composite membrane incorporated with CIP had the potential for wound dressing application.  相似文献   
116.
The Next Generation Science Standards emphasizes the inclusion of engineering practices throughout the K–12 science curriculum. Therefore, elementary educators need to be knowledgeable about engineering and engineering careers so that they can expose their students to engineering. The purpose of this study was to examine the effect of engineering professional development on in‐service elementary teachers’: (a) knowledge and perceptions regarding engineering, and (b) self‐efficacy of teaching engineering. This quantitative study revealed that even one professional development opportunity can help to alleviate some misconceptions about the work of engineers and what constitutes technology, as well as increase teachers’ confidence to teach engineering concepts.  相似文献   
117.
Objective: To investigate the differences in self-efficacy (SE) for walking tasks between older patients with knee osteoarthritis (OA) and older adults without knee OA. Methods: A cross-sectional design was employed. Older patients with radiographic knee OA and community-dwelling older adults without knee OA as controls were enrolled in the study. SE for the walking task was assessed using the modified gait efficacy scale (mGES). A Wilcoxon rank-sum test was used to compare the mGES between the groups of participants. A Tobit regression model was used to estimate the difference in mGES. The presence of radiographic knee OA was used as an independent variable. Sex (women), age, and body mass index were used as potential confounding variables in the model. Results: After exclusion, 78 participants (n=40 with knee OA, n=38 controls) were included. The mGES was lower in patients with knee OA than in controls. In the Tobit regression model adjusted for confounding factors, mGES in patients with knee OA was estimated to be 26.8 (95% confidence interval [CI]: 15.8-37.8) points lower than in controls. Conclusion: This study demonstrated that mGES was lower in older patients with knee OA than in older adults without knee OA.  相似文献   
118.
Traditional Chinese medicine consists of complex phytochemical constituents. Selecting appropriate analytical markers of traditional Chinese medicine is a critical step in quality control. Currently, the combination of fingerprinting and efficacy evaluation is considered as a useful method for screening active ingredients in complex mixtures. This study was designed to develop an orthogonal partial least squares model for screening bioactive quality control markers of QishenYiqi dripping pills based on the fingerprint–efficacy relationship. First, the chemical fingerprints of 49 batches of QishenYiqi dripping pill samples were established by ultra‐high performance liquid chromatography coupled with a photodiode array detector. Second, ultra‐high performance liquid chromatography coupled with quadrupole‐time‐of‐flight mass spectrometry was exploited to systematically investigate the 36 copossessing fingerprint components in QishenYiqi dripping pills. The vascular protective activity of QishenYiqi dripping pills was determined by using a cell counting kit‐8 assay. Finally, fingerprint–efficacy relationship was established by orthogonal partial least squares model. The results indicated that ten components exhibited strong correlation with vascular protective activity, and these were preliminarily screened as quality control markers. The present study provided a novel idea for the study of the pharmacodynamic material basis and quality evaluation of QishenYiqi dripping pills.  相似文献   
119.
This article explores green synthesis as a strategic and sustainable route to fabricate potent zinc oxide nanoparticles. Natural green based antibacterial agents and alternatives are being introduced in the market however there is a dearth in green approach moringa based zinc oxide nanoparticles in personal care products and establishing efficacy. Moringa oleifera comprises various phytochemicals that act as non-toxic stabilizing and reducing agents. Green synthesized ZnO nanoparticles (GsZnO-Nps) were investigated for their morphological and physicochemical properties using various advanced characterizing techniques. The hexagonal wurtzite structure of GsZnO-Nps is determined by X-ray diffractometry (XRD), the average crystallite size is 13.82 nm, total crystallinity was 95.91 % and high specific-surface-area is 77.38 m2/g. Scanning Electron Microscope (SEM) revealed the formation of spherical nanoparticles having a diameter of 50 nm. UV–vis spectrum shows high bandgap energy of 3.36 eV. Results have shown that antioxidant efficacy of GsZnO-Nps is significantly higher than AR-Grade ZnO, evaluated by using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) assay. Half-maximal inhibitory concentration (IC50) of GsZnO-Nps was 21.72 µg/mL and AR-Grade ZnO was 345.57 µg/mL. GsZnO-Nps (0.0183 g/mL) shows robust anti-acne efficacy against Cutibacterium acne (C. acne) organism which estimated by ZOI technique, have average ZOI of 33 mm, with standard error 0.577 mm. Antibacterial efficacy of GsZnO-Nps was established at different concentrations (10, 50, 100, and 200 µg/mL) against Gram-positive and Gram-negative pathogens by zone-of-inhibition (ZOI) method with respect to standard drugs. GsZnO-Nps at 200 µg/mL exhibits high ZOI of 26.75 mm against Escherichia coli (E. coli) and ZOI of 30 mm against Staphylococcus aureus (S. aureus) organisms respectively which is comparatively higher or equal to standard drugs. The minimum inhibitory concentration (MIC) of GsZnO-Nps is 500 µg/mL to inhibit the microbe's growth. GsZnO-Nps established the added benefits of moringa phytochemicals and is an excellent approach to developing eco-friendly and multi-functional versatile products having strong antioxidants, anti-acne and advanced antibacterial efficacy for numerous industrial applications like cosmetic, health hygiene products, drugs, therapeutic etc.  相似文献   
120.
本文针对进口螺杆压缩机中的高速驱动齿轮,对其进行了玻坏失效分析和几何参数测定。根据工作特点、运行情况和破坏现象,在选材、设计、制造、热处理和工艺参数选择等方面进行了改进性设计,达到了原设备的使用要求。本文所提供的设计方法对进口零、部件国产化的研制具有一定的参考、借鉴意义。  相似文献   
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