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11.
Sections of pancreas from 16 individuals who died with cystic fibrosis (CF) were classified by morphometric criteria into four categories in increasing order of pancreatic involvement. The concentration of acini, islets, main ducts, lobular ducts, connective tissue, and fat was compared with control levels. The results show that in the least involved pancreases, from neonates who died under 5 months of age, acini were reduced to 33% of control levels and the following were increased: islets, to 410%, lobular ducts, to 250%; and main ducts, to 1700% of controls. With increasing severity of the pancreatic disease the acini were further reduced to 5% and lobular ducts to 37% of control levels, respectively. Main ducts increased by 19-fold, and fatty infiltration accounted for more than 25% of the fresh weight of the pancreas in 9 of the 16 specimens. Comparative biochemical studies of 35 fibrocystic pancreases were quantitatively related to the severity of the pancreatic involvement as follows. Water and volatile matter, normally accounting for 80 +/-% of the weight of the fresh pancreas, was reduced to less than 30% in the most affected organs. The concentration of zinc diminished from near normal mean levels of 193 mugZn/g dry pancreas to 10% of this amount in the severely involved pancreas. Elevated concentrations of calcium, amounting to over 10 times control level, were found in obstructed ductal structures. Calcium was depleted from pancreatic sections adjacent to the obstructions. The following biochemical indicators were significantly different in their mean levels in the 35 fibrocystic pancreases when compared with the 17 controls: (P less than or equal to 0.001) fat, water, zinc, calcium, copper, magnesium, potassium, and sodium (P less than or equal to 0.01).  相似文献   
12.
Fingerprints were obtained from 100 patients with mitral valve prolapse and compared with those of 100 control subjects matched for sex and race. Arches were found in 16.8 percent of all digital patterns in patients with mitral valve prolapse but in only 2.5 percent of all digits in the control group. Whereas no patient in the control group had four or more arches, 19 percent of patients with mitral valve prolapse had this finding. In addition, arches were found on 16 and 9 percent, respectively, of digits IV and V in patients with mitral valve prolapse but were not found on these digits in the control group. The finding of four or more arches or arches on digits IV or V may be important supportive evidence of mitral valve prolapse when evaluating patients with atypical chest pain and palpitations. Antenatal factors may be involved in the pathogenesis of mitral valve prolapse since it is possible that a genetic or environmental factor that interferes with the development of the mitral valve may also influence epidermal ridge patterns.  相似文献   
13.
Gonadal hormones affect body composition, food intake, weight gain and serum lipids in numerous species including man. In this study, mature male Sprague-Dawley rats were castrated or sham-operated at 16 weeks of age. During the 6-week observation period with weekly records of food intake and weight gain, these parameters were significantly lower in the castrated group. The decrease in food intake in this group could not account for the difference in body weight between the groups, indicating a lower feed utilisation in the castrates. At sacrifice accessory reproductive organs, the levator ani muscle, thymus and adrenals were dissected for determination of organ weight and histology, revealing significant reductions in the accessory reproductive organs and levator ani of the castrates. The thymus was significantly heavier in the castrated animals. No differences were found in the adrenals. Two of the sham-operated animals had signs of accidental functional castration. The proportion of body cell mass and total lipid of the carcass was the same in both groups. Significant reductions in adipocyte weights were found in the epididymal depots of the castrated rats. Blood samples taken at sacrifice in pentobarbital anaesthesia were analysed for glucose, insulin, triglycerides, cholesterol, FFA, glycerol and protein. Statistically significant reductions in triglycerides and protein were recorded in the castrated animals without any significant changes in the other parameters studied. The results are discussed with reference to the age of castration and the importance of the reduced food intake in castrated animals.  相似文献   
14.
A study was performed utilizing 3 mock eyes of different sizes to determine the precision and accuracy of 3 radiographic methods of localization of intraorbital foreign bodies. The Comberg method was found to be the most precise and accurate, next, the Sweet method, and then the modified spectacle frame method. However, the modified spectacle frame field expedient method of localization yielded a surprisingly high degree of accuracy in 2 of the 3 planes of reference, that is, mediolaterally and superointeriorly. A more accurate field expedient type of device which will permit greater accuracy in localization of intraorbital foreign bodies in the anteroposterior axis is currently under development.  相似文献   
15.
利用对环境友好的酸性皂土做催化剂,糠醛与乙酸酐发生缩合反应合成了1,1-二乙酸酯,产率高达86.6%。实验结果表明,酸性皂土催化该反应具有价廉无污染、选择性高、反应条件温和、反应时间短、后处理简单、易回收、可重复利用等优点。  相似文献   
16.
目的:研究半乳聚糖的快速、高效制备方法,并对产物进行结构分析。方法:在微波辐照下,以半乳糖为底物,氯化钠溶液为引发剂,杂多酸为反应催化剂,催化底物脱水缩合生成半乳聚糖,并通过乙醇沉淀去除催化剂和引发剂,Sephadex G-25葡聚糖凝胶柱分级纯化,高效凝胶渗透色谱分析半乳聚糖的纯度及聚合度,高效阴离子交换色谱分析单糖组成,最后通过红外光谱分析半乳聚糖的构型。结果:半乳聚糖的最优合成条件为引发剂浓度0.25 mol/L、催化剂添加量1.1%、反应温度130 ℃、微波辐照4.5 min,半乳糖转化率为97.22%。半乳聚糖的平均分子质量为2.853 kD,平均聚合度为17。单糖组成为半乳糖及微量葡萄糖。红外光谱及氢核磁共振波谱(1H-nuclearmagnetic resonance,1H-NMR)分析表明半乳聚糖残基以β-构型为主。结论:可以通过微波辐照杂多酸催化的方法快速、高效制备半乳聚糖。  相似文献   
17.
采用中性红细胞毒性试验测试了不同透气度接装纸卷烟和不同吸阻滤棒卷烟烟气冷凝物的细胞毒性,并初步分析了卷烟烟气的细胞毒性指标与CO,NNK,NH3,HCN,B[a]P,巴豆醛和苯酚释放量之间的相关性.结果表明:①随着接装纸透气度的增大,卷烟烟气冷凝物的细胞毒性呈降低趋势;细胞毒性指标与CO,NNK,NH3,HCN,B[a]P,巴豆醛和苯酚的释放量之间具有一定的相关性;②随着滤棒吸阻的增大,卷烟烟气冷凝物的细胞毒性呈降低趋势;细胞毒性指标与NH3,HCN,B[a]P和苯酚的释放量之间具有一定的相关性.  相似文献   
18.
分析了聚丙烯(PP)滤嘴卷烟和醋纤(CA)滤嘴卷烟烟气常规成分和挥发性半挥发性成分的释放量.结果表明:①两种滤嘴卷烟的总粒相物、烟碱、焦油和CO释放量相当;②PP滤嘴卷烟大部分挥发性半挥发性成分的释放量都比CA滤嘴卷烟高或者相当,而且PP滤嘴卷烟与CA滤嘴卷烟释放量比值波动较大;③PP滤嘴卷烟烟气中糠醛、糠醇、苯乙醛、吡啶、乙酸、苯酚、对+间甲酚和邻甲酚的释放量远远高于CA滤嘴卷烟.  相似文献   
19.
目的:研究鱼胶原蛋白肽(fish collagen peptides,FCPs)对高脂膳食(high-fat diet,HFD)小鼠肝脏脂肪代谢和氧化还原状态的影响。方法:54?只C57BL/6雄性小鼠按体质量随机分为正常膳食组(CON)、HFD组(HF)和FCPs干预HFD组(PHF)。每周记录各组小鼠体质量,并按体质量把每组小鼠随机均分为两批,分别在第11和22周宰杀,测定采食量、脂肪表观消化率;肝脏中甘油三酯(triglyceride,TG)、总胆固醇和游离脂肪酸(free fatty acid,FFA)含量;肝脏脂代谢相关基因乙酰辅酶A羧化酶1、脂肪酸合成酶、固醇调节元件结合蛋白1c、胆固醇7α-羟化酶(cholesterol 7α-hydroxylase 1,CYP7A1)、过氧化物激活受体α(peroxisome proliferator activated receptor α,PPARα)和肉毒碱棕榈酰基转移酶1(carnitine palmity1 transferase 1,CPT1)的mRNA表达水平,肝脏氧化还原状态相关指标活性氧自由基(reactive oxygen species,ROS)、丙二醛、总抗氧化能力(total antioxidant capacity,T-AOC)、谷胱甘肽过氧化物酶(glutathion peroxidase,GSH-Px)活力和还原型/氧化型谷胱甘肽的水平。结果:第22周时,与HF组相比,PHF组小鼠的采食量、脂肪和能量摄入显著增加(P<0.05),肝脏的TG、FFA、脂肪空泡和脂肪浸润面积比明显降低(P<0.05),脂肪分解关键基因CYP7A1、PPARα和CPT1的mRNA表达水平显著上调(P<0.05),肝脏的ROS水平显著降低(P<0.05),T-AOC水平和GSH-Px活力显著升高(P<0.05)。结论:质量分数1% FCPs干预可能通过改善HFD小鼠肝脏氧化还原状态,促进肝脏脂肪分解代谢,起到减少小鼠肝脏脂肪蓄积和改善脂代谢。  相似文献   
20.
目的:研究饮食蛋氨酸限制对高脂饮食小鼠肠道氧化还原状态、炎症和菌群的影响。方法:将27 只SPF级雄性C57BL/6小鼠随机分为3 组,分别为正常饮食组(C:0.86%(质量分数,下同)蛋氨酸、4%猪油)、高脂饮食组(HM:0.86%蛋氨酸、20%猪油)、高脂蛋氨酸限制组(LM:0.17%蛋氨酸、20%猪油),每周测定小鼠体质量,12 周实验结束后处死小鼠,并取血液、回肠、盲肠和结肠样品,测定血浆胆固醇(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)、脂多糖(lipopolysaccharide,LPS)和LPS结合蛋白(LPS-binding protein,LBP)的含量;测定回肠和结肠组织中氧化应激相关指标;用实时荧光定量聚合酶链式反应测定回肠炎症基因肿瘤坏死因子-α(tumour necrosis factor-α,TNF-α)、白介素-6(interleukin-6,IL-6)mRNA的表达水平;提取盲肠内容物DNA,用限制性末端酶切的方法分析小鼠盲肠内容物中菌群的变化;提取结肠内容物DNA,用高通量测序分析小鼠结肠内容物中菌群的变化。结果:与HM组相比,LM组小鼠体质量、血浆TC、TG和LDL-C水平显著降低(P<0.05,P<0.01),HDL-C水平极显著增加(P<0.01);回肠总抗氧化能力和还原型谷胱甘肽/氧化型谷胱甘肽(glutathione/oxidizided glutathione,GSH/GSSG)的比值显著增加(P<0.05);结肠GSH/GSSG比值显著增加(P<0.05),丙二醛含量显著降低(P<0.05);血浆LPS和LBP水平显著降低(P<0.05,P<0.01);回肠TNF-α、IL-6 mRNA的表达水平显著下调(P<0.05);盲肠菌群Shannon-Weiner指数与均匀度指数显著上升(P<0.05),结肠菌群中双歧杆菌和颤螺杆菌丰度显著增加(P<0.05)。结论:饮食蛋氨酸限制具有显著改善高脂饮食小鼠肠道组织氧化还原状态、炎症反应和菌群结构的作用。  相似文献   
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