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Shuangshuang Song Baocheng Tian Fen Chen Wenji Zhang Yusheng Pan Qiang Zhang 《Drug development and industrial pharmacy》2015,41(1):51-62
Objective: The objectives of this study were, first, to develop a free-flowing and stable proniosome formulation for poorly water-soluble drugs such as vinpocetine; and second, to estimate its bioavailability as oral drug delivery system.Methods: The proniosomes consisting of span60, cholesterol, sorbitol and vinpocetine were prepared by a novel approach. After the proniosomes were contacted with water, the suspension of vinpocetine-loaded niosomes formed automatically. The proniosomes and reconstituted niosomes were evaluated for their physicochemical characteristics, in vitro drug dissolution and release, integrity and stability at different GI tract pH conditions, in situ single-pass intestinal perfusion and in vivo bioavailability.Results: The proniosome powder exhibited excellent flowability. The reconstituted niosomes with high drug entrapment efficiency (89.67?±?3.28%) showed spherical morphology with smooth surface under transmission electron microscope (TEM). X-ray diffraction (XRD) indicated that the drug was in an amorphous or molecular state in proniosome powder. In vitro dissolution and release study, proniosomes did enhance the dissolution and release rate compared to vinpocetine suspension in phosphate buffer solution (pH 7.2). Proniosome-derived niosomes could keep their integrity and stability at different GI tract pH conditions. The in situ single-pass intestinal perfusion indicated that encapsulation of vinpocetine into niosomes could largely improved the absorption of vinpocetine. The AUC(0?∞) of F2 and F3 was about 4.0- and 4.9-fold higher than that of the vinpocetine suspension, respectively. The results demonstrated the proniosomes indeed remarkably enhanced the oral bioavailability of vinpocetine.Conclusion: This study suggested the potential of proniosomes as stable precursors for the immediate preparation of niosome carrier systems. 相似文献
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目的 通过开展抗菌药物临床应用专项整治活动,探讨南昌大学第一附属医院介入手术围术期预防用药的合理性.方法收集该院2013年3-5月住院的1 160例10种介入手术病例的抗菌药物使用情况,并对其合理性进行分析.结果 永久或临时起搏器安置/更换术、椎间盘射频消融术的预防使用抗菌药物的使用率分别是87.95%、83.33%,其他8种介入手术的使用率都为0.结论 该院介入手术围术期抗菌药物的使用率已趋达到卫生部的标准,呈整体合理趋势.加大对医护人员的培训和监督力度,能够明显改善抗菌药物用药不合理的局面. 相似文献
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目的: 探讨胰岛素样生长因子1(IGF-1)基因多态性与抗高血压药物治疗后血压水平的关联性。方法: 运用流行病学现况调查方法,收集服用复方利血平、降压片和珍菊降压片的780例高血压患者的一般临床特征并测量其血压和临床生化指标。选择IGF-1基因的5个标签位点,采用TaqMan技术进行基因分型。采用协方差分析及分层分析对其基因多态性与药物治疗后血压水平的关系进行评价。结果: 在服用降压片的高血压病人中,rs6219位点不同基因型之间舒张压水平差异有统计学意义(P=0.01)。在服用复方利血平的高血压病人中,rs5742612和rs6218位点不同基因型之间收缩压水平差异有统计学意义(P值分别为0.04、0.017)。在服用珍菊降压片的高血压患者中,rs6218位点不同基因型之间舒张压水平及rs6219位点不同基因型之间收缩压水平差异均有关联(P值分别为0.017、0.033)。进一步分层分析发现,服用降压片的患者中,随着rs35767位点遗传变异女性收缩压的水平呈线性下降,而男性舒张压水平呈线性上升,校正混杂因素后P值分别为0.028、0.038。结论: IGF-1基因多态性与复方利血平、降压片和珍菊降压片三种抗高血压药物治疗后血压水平均有显著相关,提示IGF-1基因可能是高血压重要的药物疗效生物标记。 相似文献
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膀胱癌化疗药物增敏机制研究进展 总被引:1,自引:0,他引:1
近年来化疗耐药严重制约着膀胱癌的治疗效果,术后复发率和转移率居高不下。因此,逆转膀胱癌化疗耐药性,寻找有效的化疗增敏靶点并探究其机制十分重要。目前临床上多采用经尿道膀胱肿瘤切除术,术后选择辅助化疗药物进行治疗,常用化疗药物包括顺铂、吉西他滨、阿霉素、表柔比星等。目前实现这些药物化疗增敏的靶点基因和分子在膀胱癌细胞中呈现不同的表达状态,且通过这些靶点实现增敏的机制也各有不同。本文将就膀胱癌化疗药物增敏靶点及机制的研究进展进行综述,以期为膀胱癌的化疗增敏探索新的思路。 相似文献
47.
Dendrimers are novel three dimensional, hyperbranched globular nanopolymeric architectures. Attractive features like nanoscopic size, narrow polydispersity index, excellent control over molecular structure, availability of multiple functional groups at the periphery and cavities in the interior distinguish them amongst the available polymers. Applications of dendrimers in a large variety of fields have been explored. Drug delivery scientists are especially enthusiastic about possible utility of dendrimers as drug delivery tool. Terminal functionalities provide a platform for conjugation of the drug and targeting moieties. In addition, these peripheral functional groups can be employed to tailor-make the properties of dendrimers, enhancing their versatility. The present review highlights the contribution of dendrimers in the field of nanotechnology with intent to aid the researchers in exploring dendrimers in the field of drug delivery. 相似文献
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丙型病毒性肝炎(viral hepatitis type C,HC),系丙型肝炎病毒(HCV)感染所引起的疾病,HCV感染影响着全世界近2亿人群,是引起慢性肝脏疾病的主要病因,进一步会引起肝硬化、肝癌和肝功能衰竭。本文主要介绍HCV及其结构、基于不同靶点的治疗丙肝的药物(标准方案、DAA药物、DAA药物联合标准方案、DAA药物相联合、其他药物联合、HCV疫苗等)的最新研发动态,并对目前的研发现状进行了展望。 相似文献
50.
Cosmin Stefan Mocanu Marius Niculaua Gheorghita Zbancioc Violeta Mangalagiu Gabi Drochioiu 《International journal of molecular sciences》2022,23(5)
Our work discusses the investigation of 75 peptide-based drugs with the potential ability to break the β-sheet structures of amyloid-beta peptides from senile plaques. Hence, this study offers a unique insight into the design of neuropeptide-based drugs with β-sheet breaker potential in the amyloid-beta cascade for Alzheimer’s disease (AD). We started with five peptides (15QKLVFF20, 16KLVFF20, 17LVFF20, 16KLVF19 and 15QKLV18), to which 14 different organic acids were attached at the N-terminal. It was necessary to evaluate the physiochemical features of these sequences due to the biological correlation with our proposal. Hence, the preliminary analysis of different pharmacological features provided the necessary data to select the peptides with the best biocompatibility for administration purposes. Our approaches demonstrated that the peptides 17LVFF20, NA-17LVFF20, 16KLVF19 and NA-16KLVF19 (NA-nicotinic acid) have the ability to interfere with fibril formation and hence improve the neuro and cognitive functions. Moreover, the peptide conjugate NA-16KLVF19 possesses attractive pharmacological properties, demonstrated by in silico and in vitro studies. Tandem mass spectrometry showed no fragmentation for the spectra of 16KLVF19. Such important results suggest that under the action of protease, the peptide cleavage does not occur at all. Additionally, circular dichroism confirmed docking simulations and showed that NA-16KLVF19 may improve the β-sheet breaker mechanism, and thus the entanglement process of amyloid-beta peptides can be more effective. 相似文献