首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   165篇
  免费   16篇
  国内免费   2篇
综合类   3篇
化学工业   55篇
金属工艺   2篇
机械仪表   2篇
轻工业   109篇
石油天然气   2篇
无线电   1篇
一般工业技术   7篇
冶金工业   2篇
  2023年   6篇
  2022年   9篇
  2021年   12篇
  2020年   11篇
  2019年   10篇
  2018年   5篇
  2017年   8篇
  2016年   2篇
  2015年   6篇
  2014年   9篇
  2013年   16篇
  2012年   15篇
  2011年   12篇
  2010年   11篇
  2009年   7篇
  2008年   6篇
  2007年   11篇
  2006年   11篇
  2005年   5篇
  2004年   4篇
  2003年   2篇
  2002年   1篇
  1999年   3篇
  1989年   1篇
排序方式: 共有183条查询结果,搜索用时 15 毫秒
1.
While exercise training (ET) is an efficient strategy to manage obesity, it is recommended with a dietary plan to maximize the antiobesity functions owing to a compensational increase in energy intake. Capsiate is a notable bioactive compound for managing obesity owing to its capacity to increase energy expenditure. We aimed to examine whether the antiobesity effects of ET can be further enhanced by capsiate intake (CI) and determine its effects on resting energy expenditure and metabolic molecules. Mice were randomly divided into four groups (n = 8 per group) and fed high-fat diet. Mild-intensity treadmill ET was conducted five times/week; capsiate (10 mg/kg) was orally administered daily. After 8 weeks, resting metabolic rate and metabolic molecules were analyzed. ET with CI additively reduced the abdominal fat rate by 18% and solely upregulated beta-3-adrenoceptors in adipose tissue (p = 0.013) but did not affect the metabolic molecules in skeletal muscles. Surprisingly, CI without ET significantly increased the abdominal fat rate (p = 0.001) and reduced energy expenditure by 9%. Therefore, capsiate could be a candidate compound for maximizing the antiobesity effects of ET by upregulating beta-3-adrenoceptors in adipose tissue, but CI without ET may not be beneficial in managing obesity.  相似文献   
2.
3.
Muscle disuse and denervation leads to muscle atrophy, but underlying mechanisms can be different. Previously, we have found ceramide (Cer) accumulation and lipid raft disruption after acute hindlimb suspension (HS), a model of muscle disuse. Herein, using biochemical and fluorescent approaches the influence of unilateral denervation itself and in combination with short-term HS on membrane-related parameters of rat soleus muscle was studied. Denervation increased immunoexpression of sphingomyelinase and Cer in plasmalemmal regions, but decreased Cer content in the raft fraction and enhanced lipid raft integrity. Preliminary denervation suppressed (1) HS-induced Cer accumulation in plasmalemmal regions, shown for both nonraft and raft-fractions; (2) HS-mediated decrease in lipid raft integrity. Similar to denervation, inhibition of the sciatic nerve afferents with capsaicin itself increased Cer plasmalemmal immunoexpression, but attenuated the membrane-related effects of HS. Finally, both denervation and capsaicin treatment increased immunoexpression of proapoptotic protein Bax and inhibited HS-driven increase in antiapoptotic protein Bcl-2. Thus, denervation can increase lipid raft formation and attenuate HS-induced alterations probably due to decrease of Cer levels in the raft fraction. The effects of denervation could be at least partially caused by the loss of afferentation. The study points to the importance of motor and afferent inputs in control of Cer distribution and thereby stability of lipid rafts in the junctional and extrajunctional membranes of the muscle.  相似文献   
4.
本实验发明了一种化合物组合:新型乳化剂、天然植物碱、纳米降解剂、助溶剂、天然香型和水等组成。通过试验筛选出最佳配方,并且测定了该清洁剂的去污能力、杀菌能力、对残留农药降解效果、泡沫性能、表面张力和稳定性。结果表明,该产品制备简便、综合洗洁性能好,具有较大市场前景。  相似文献   
5.
张晓春  于良民  姜晓辉 《材料导报》2018,32(2):193-197, 202
以取代芳烃和N-羟甲基丙烯酰胺为原料,采用傅克烷基化反应合成了四种含辣素衍生结构单体:4-羟基-2-甲基-5-甲硫基苄基丙烯酰胺(A)、2-羟基-4-丙烯酰胺甲基-5-甲硫基-6-甲基苄基丙烯酰胺(B)、3-丙烯酰胺甲基-2-羟基苯甲酰胺(C)和1-丙烯酰胺甲基-2-萘酚(D),并通过红外光谱(IR)和核磁氢谱(1 H NMR)对其结构进行了表征。抑菌实验结果表明化合物D对两种受试菌(金黄色葡萄球菌和大肠杆菌)的抑制活性最高,最小抑菌浓度均可达到0.187 5mg/mL,且D对两种受试藻(三角褐指藻和新月菱形藻)的抑制活性也最高。以四种化合物为功能单体合成出树脂,树脂对受试藻均具有较高的抑制活性,含化合物D的树脂的抑制活性最高,72h后抑制率均可达到50%以上。  相似文献   
6.
目的 探究贵州主栽辣椒的品质差异,并进行样品品质综合性评价。方法 对25种贵州主栽辣椒的营养指标进行测定,针对品质指标进行统计分析、相关性分析和聚类分析。结果 25种辣椒果实的含水量、辣椒红素、还原糖、总氨基酸、粗脂肪、粗纤维、辣椒素和二氢辣椒素的平均含量分别为0.53 g/g、56.68μg/g、11.08 mg/g、34.86μmol/g、14.95%、22.41%、2.20 g/kg、1.11 g/kg。各个品质在不同材料间的差异明显,其中以二氢辣椒素含量的变异系数最大,达70.24%,最小的为粗纤维,只有13.19%。通过隶属函数分析可知,综合品质最优的品种为黔椒11号。通过相关性分析得出辣椒红素与还原糖、总氨基酸显著负相关(P<0.05),与辣椒素、二氢辣椒素显著正相关(P<0.05);还原糖与总氨基酸、辣椒素显著负相关(P<0.05),与粗脂肪、粗纤维、二氢辣椒素显著正相关(P<0.05);总氨基酸与粗脂肪、含水量、辣椒素、二氢辣椒素显著正相关(P<0.05);粗纤维与辣椒素显著正相关(P<0.05)。通过聚类分析将所有样品分为4类。第1...  相似文献   
7.
Nerve growth factor (NGF) is known to intensify pain in various ways, so perturbing pertinent effects without negating its essential influences on neuronal functions could help the search for much-needed analgesics. Towards this goal, cultured neurons from neonatal rat trigeminal ganglia—a locus for craniofacial sensory nerves—were used to examine how NGF affects the Ca2+-dependent release of a pain mediator, calcitonin gene-related peptide (CGRP), that is triggered by activating a key signal transducer, transient receptor potential vanilloid 1 (TRPV1) with capsaicin (CAP). Measurements utilised neurons fed with or deprived of NGF for 2 days. Acute re-introduction of NGF induced Ca2+-dependent CGRP exocytosis that was inhibited by botulinum neurotoxin type A (BoNT/A) or a chimera of/E and/A (/EA), which truncated SNAP-25 (synaptosomal-associated protein with Mr = 25 k) at distinct sites. NGF additionally caused a Ca2+-independent enhancement of the neuropeptide release evoked by low concentrations (<100 nM) of CAP, but only marginally increased the peak response to ≥100 nM. Notably, BoNT/A inhibited CGRP exocytosis evoked by low but not high CAP concentrations, whereas/EA effectively reduced responses up to 1 µM CAP and inhibited to a greater extent its enhancement by NGF. In addition to establishing that sensitisation of sensory neurons to CAP by NGF is dependent on SNARE-mediated membrane fusion, insights were gleaned into the differential ability of two regions in the C-terminus of SNAP-25 (181–197 and 198–206) to support CAP-evoked Ca2+-dependent exocytosis at different intensities of stimulation.  相似文献   
8.
利用色差仪、气相色谱-质谱联用和紫外可见光分光光度计等仪器对不同油温浸提辣椒油的色泽、挥发性成分及辣椒素进行分析.结果表明:油温为140℃时辣椒油色泽鲜红,随着油温上升,辣椒油的色泽逐渐变亮,红色程度降低;当油温超过180℃后,辣椒油色泽明显变暗变黑.辣椒油中挥发性成分共有58种,分为13类,分别为醛类化合物、醇类化合...  相似文献   
9.
目的:探讨辣椒素剂量对去势雌性大鼠血脂、肝脂及盲肠内环境的影响。方法:选用30 只雌性SD大鼠随机分组为5 组,其中1 组大鼠进行伪切除手术作对照(伪切除组),另外4 组大鼠做双侧卵巢切除手术,基础饲料喂养恢复1 周后,分为不灌胃辣椒素(空白组)和灌胃5.0、10.0、15.0 mg/(kg·d)辣椒素剂量组(低、中、高剂量组)。喂食相同基础饲料28 d后解剖,测定大鼠血清和肝脏中胆固醇、甘油三酯含量及盲肠面积,盲肠内容物水分含量、pH值、短链脂肪酸和微生物等指标。结果:空白组大鼠的体质量、采食量、血脂、肝脏总脂肪、总胆固醇、甘油三酯总含量均显著高于伪切除组。辣椒素可降低双侧卵巢切除大鼠的体质量增加量、血清和肝脏中胆固醇和甘油三酯含量,且具有明显的剂量关系;同时可以降低盲肠组织总质量、盲肠体质量比、盲肠内容物短链脂肪酸含量,显著降低盲肠内容物有益菌数量(P<0.05);辣椒素可以显著升高游离氨含量和pH值,增加有害菌数量(P<0.05),但辣椒素各剂量组之间没有显著性差异。结论:辣椒素对因雌激素缺乏引起高脂血症雌性大鼠具有较好的降血脂、降肝脂作用,但对盲肠内环境具有一定的损伤作用。  相似文献   
10.
以6-溴己酸为起始原料,经Wittig反应、胺化还原反应、N-酰化反应,制备了N-[(4-羟基-3-甲氧基苯基)-甲基]-8-甲基-6-壬烯酰胺,经EI-MS、1H NMR等测试技术分析确定了目标化合物的分子结构。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号