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51.
52.
Bio-ethanol production from algae is a promising way to help solve the energy problem. Alginate is a major component of algae, but it cannot be utilized by existing ethanol fermentation microorganisms. In order to improve the utilization rate of brown algae, high alginate fermentation strains should be obtained. In this research, strains for algae fermentation were got from several experiments. The ethanol yield of strain A was the highest, which was 0.095 g/g (ethanol to alginate). The identification of strain A was carried out and it was 99% identical to Pantoea sp. F16-PCAi-T3P21. Fermentation experiments with different substrates were carried out, such as laminaran, mannitol, L. japonica and acid hydrolysate of L. japonica, and the ethanol yield rate of L. japonica acid hydrolysate was the highest, which reached 0.17 g/g ethanol to L. japonica. It showed that strain A can converse alginate to ethanol in a relatively high yield rate, and might be a promising strain with L. japonica as the substrate, we believe more research should be carried out on this strain.  相似文献   
53.
本文研究了用不同方法提取的紫萁粗多糖中蛋白质的含量、性质及脱除方法。结果表明:室温提取扭多糖中蛋白质的含量为17.5%,沸水浴提取粗多糖中蛋白质含量为32.7%,其中大多数为游离蛋白质。用3%TCA和Sevag试剂相结合,在室温下脱蛋白质效果良好。为紫萁多糖纯化和结构分析奠定前期工作基础。  相似文献   
54.
于颖 《毛纺科技》2020,48(3):36-40
为丰富槐米色素和高粱红色素的染色色系,解决其染色色调偏少和配色困难的问题,对这2种染料在桑蚕丝织物上进行不同浓度配比的拼色研究。探讨了直接染色和媒染染色对染色性能的影响,测试了桑蚕丝织物的K/S值及染色牢度。结果表明:槐米色素和高粱红色素具有良好的拼色性能,染色桑蚕丝织物的色光、色深值随着染料浓度配比的变化呈现规律性变化,染色效果较好,可获得多种颜色。媒染染色进一步丰富了色泽,提高了桑蚕丝织物的染色深度和色牢度,各项色牢度均达到3级以上。  相似文献   
55.
目的:GC法和HPLC法分析金银花多糖的单糖组成,并对两种方法进行比较。方法:金银花多糖经2.0 mol·L-1的三氟乙酸水解后,用糖腈乙酸酯衍生化-GC法和1-苯基-3-甲基-5-吡唑啉酮(PMP)柱前衍生化-HPLC法分别测定其单糖组成及其比例。结果:GC法检测出金银花多糖由鼠李糖(L-Rha)、阿拉伯糖(D-Ara)、甘露糖(D-Man)、木糖(D-Xyl)、葡萄糖(D-Glc)、半乳糖(D-Gal)组成;HPLC法检测到金银花多糖中含有甘露糖(D-Man)、鼠李糖(L-Rha)、葡萄糖醛酸(D-GlcA)、葡萄糖(D-Glc)、半乳糖(D-Gal)、阿拉伯糖(D-Ara)和木糖(D-Xyl),其中半乳糖(D-Gal)与阿拉伯糖(D-Ara)的色谱峰重叠。结论:两种方法均能检测出中性糖,HPLC法不仅能测中性糖,还能检测出葡萄糖醛酸,对金银花多糖的单糖组成分析GC与HPLC联合使用较为合适。  相似文献   
56.
Flash flooding is a major environmental stressor affecting rice production worldwide. DT3 is a drought-tolerant, recurrent parent with a good yield, edible quality, and agronomic traits akin to those of an elite Taiwanese variety, Taiken9 (TK9). Progenies carrying Sub1A can enhance submergence stress tolerance and can be selected using the marker-assisted backcross (MAB) breeding method. For foreground selection, Sub1A and SubAB1 were utilized as markers on the BC2F1, BC3F1, and BC3F2 generations to select the submergence-tolerant gene, Sub1A. Background selection was performed in the Sub1A-BC3F2 genotypes, and the percentages of recurrent parent recovery within individuals ranged from 84.7–99.55%. BC3F3 genotypes (N = 100) were evaluated for agronomic traits, yield, and eating quality. Four of the eleven BC3F4 lines showed good yield, yield component, grain, and eating quality. Four BC3F4 lines, SU39, SU40, SU89, and SU92, exhibited desirable agronomic traits, including grain quality and palatability, consistent with those of DT3. These genotypes displayed a high survival rate between 92 and 96%, much better compared with DT3 with 64%, and demonstrated better drought tolerance compared to IR64 and IR96321-345-240. This study provides an efficient and precise MAB strategy for developing climate-resilient rice varieties with good grain quality for flood-prone regions.  相似文献   
57.
目的:研究蓝靛果花色苷对高脂血症大鼠肝脏肝X受体(liver X receptor α,LXRα)、B族I型清道夫受 体(scavenger receptor class B, type I,SR-BI)、三磷酸腺苷结合盒转运蛋白G5(ATP-binding cassette transporter G5,ABCG5)、过氧化物酶体增殖物激活受体(peroxisome proliferator-activated receptor γ,PPARγ)及胆固醇7α-羟化 酶(cholesterol 7α-hydroxylase,CYP7a1)基因表达的影响。方法:选择2 月龄雄性Wistar大鼠60 只,将大鼠随机分为 6 组,其中10 只给予普通饲料,其余50 只给予高脂饲料。30 d造模成功后,分别建立基础饲料正常对照组(ND, 灌胃1.2 g/(kg·d)生理盐水)、高脂模型对照组(HFD,灌胃1.2 g/(kg·d)生理盐水)、阳性对照组(灌 胃10 mg/(kg·d)辛伐他汀片)和蓝靛果花色苷低(HFD+L)、中(HFD+M)、高(HFD+H)剂量组(分别灌 胃4.0、40.0、120.0 mg/(kg·d)蓝靛果花色苷),持续28 d。利用实时荧光定量聚合酶链式反应检测大鼠肝脏组 织中LXRα、SR-BI、ABCG5、PPARγ及CYP7a1 mRNA的表达情况。结果:经蓝靛果花色苷干预后,与HFD组相比: 蓝靛果花色苷各剂量组肝脏中SR-BI、ABCG5 mRNA表达几乎不受影响,且无显著性差异(P>0.05);HFD+M、 HFD+H组LXRα、CYP7a1 mRNA表达升高且差异极显著(P<0.01);HFD+L、HFD+M、HFD+H组 PPARγ mRNA表达降低且差异极显著(P<0.01)。结论:蓝靛果花色苷通过提高高脂血症大鼠肝脏内LXRα、 CYP7a1 mRNA表达,降低PPARγ mRNA表达来调节高脂血症大鼠的血脂水平,预防动脉硬化的发生。 关键词:蓝靛果;蓝靛果花色苷;高脂血症大鼠;肝X受体;B族I型清道夫受体;三磷酸腺苷结合盒转运蛋白G5; 过氧化物酶体增殖物激活受体γ;胆固醇7α-羟化酶  相似文献   
58.
目的:研究蓝靛果花色苷对高脂血症大鼠肝脏低密度脂蛋白受体(low density lipoprotein receptor, LDLR)、三磷酸腺苷结合盒转运体G1(ATP-binding cassette transporter G1,ABCG1)及ABCA1基因表达的影响。 方法:选择2 月龄雄性Wistar大鼠60 只,将大鼠随机分为6 组,分别为基础饲料对照组(ND,1.2 g/(kg·d mb) 生理盐水灌胃)、高脂模型对照组(HFD,1.2 g/(kg·d mb)生理盐水灌胃)、阳性对照组(10 mg/(kg·d mb) 辛伐他汀片灌胃),蓝靛果花色苷低、中、高剂量组(HFD+L、HFD+M、HFD+H,分别给予4.0、40.0、 120.0 mg/(kg·d mb)的花色苷灌胃),持续28 d。实验结束后,测定血清总胆固醇(total cholesterol,TC)、 甘油三酯(triglyceride,TG)、高密度脂蛋白胆固醇(high density lipoprotein cholesterol,HDL-C)、低密 度脂蛋白胆固醇(low density lipoprotein cholesterol,LDL-C)、载脂蛋白A(apolipoprotein A,Apo-A)及载 脂蛋白B(Apo-B)等血脂指标水平。取大鼠肝脏,利用实时荧光定量聚合酶链式反应测定大鼠肝脏组织中 LDLR、ABCG1、ABCA1 mRNA表达量,Western blot检测LDLR蛋白表达水平。结果:蓝靛果花色苷干预后, 与HFD组相比,花色苷均能不同程度地降低高血脂大鼠血清中TC、TG、LDL-C、Apo-B的含量(P<0.05或 P<0.01),显著升高HDL-C及Apo-A的含量(P<0.05或P<0.01)。花色苷各剂量组LDLR蛋白和mRNA水平均增 高,与HFD组比较差异有显著性(P<0.05),ABCA1 mRNA和ABCG1 mRNA的表达水平也高于HFD组,尤其是花 色苷中、高剂量组差异明显(P<0.05)。结论:40.0 mg/(kg·d mb)蓝靛果花色苷具有明显的调节血脂作用,其 作用机制可能是通过上调肝脏LDLR和ABC家族基因的表达,进而调节胆固醇逆转运过程。  相似文献   
59.
响应面分析法优化槐米总黄酮的提取工艺   总被引:3,自引:0,他引:3  
通过对槐米总黄酮提取,考察体积分数、提取时间、提取温度、料液比四因素对槐米总黄酮提取率的影响.用RAS软件程序对试验数据进行二次响应面分析,对3项工艺参数进行优化,得出槐米总黄酮提取的二次回归方程;通过分析得出槐米总黄酮提取的最佳条件为:60%乙醇(体积分数),提取2.2 h,料液比(g:mL)1:17.9,温度80.0℃.在此条件下测得的总黄酮提取率为18.46%.  相似文献   
60.
The beauty of ideal skin texture is closely associated with dermal moisture factors. The key factors of skin moisture are NMF (natural moisturizing factor) and skin normal barrier function. The former keeps dermal surface moisture, and the later protects from excess water loss. So we have searched for the ingredient that improves these factors. Birch sap has been widely used as an effective drink for anti-fatigue and anti-stress. However, the effect of birch sap on skin as a cosmetic agent has not been known entirely. In this study, we investigated the effects of birch ( Betula platyphylla Sukatchev var. japonica Hara) sap on human skin. Birch sap induced epidermal keratinocyte differentiation properties in vitro . We assessed two epidermal differentiation agents. Filaggrin is a precursor protein of NMF, and involucrin is one of the precursor proteins of the cornified cell envelope (CE), which is related to normal barrier function. We have evaluated the production of these proteins where birch sap was applied to human normal keratinocytes. Birch sap not only increased mRNA expression of filaggrin and involucrin, but also accelerated these proteins production. Otherwise, birch sap did not have any influence for IL-6 production, which is related to inflammatory and aberrant keratinocyte proliferation. The results of induced differentiation properties on birch sap-treated keratinocytes are very similar to the differentiation induced by calcium in vitro . This similarity suggested that birch sap has a differentiation inducible property on in vitro cultured keratinocytes. Our study suggested that birch sap is able to control both moisturizing- and barrier-related factor production. From these effects, birch sap provides appropriate epidermal functions and skin homeostasis, and revealed itself as a very useful ingredient in the cosmetic field.  相似文献   
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