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1.
为了系统地评价胸腺五肽作为辅助药物治疗各种肺癌的疗效及其对机体免疫功能的影响,利用电子检索收集有关胸腺五肽联合放疗或化疗方案治疗肺癌的临床随机对照试验文献,对符合纳入标准的文献,采用RevMan5.3 软件进行系统评价。最终共纳入文献 9 篇,总样本量 784 例。Meta 分析结果表明,胸腺五肽作为辅助药物治疗各种肺癌提高总有效率的差异无统计学意义[OR = 1.44, 95%CI(0.99, 2.10), P =0.06 > 0.05]。在对免疫功能的影响方面,胸腺五肽的使用显著增高外周血中的 CD3+ 细胞水平[OR = 5.88, 95% CI(2.34, 9.42), P =0.001],CD4+ 细胞水平也显著上升[OR =8.32, 95%CI(5.22, 11.42), P < 0.00001] , CD4+ /CD8+比值也有明显的提高[OR = 0.38, 95% CI(0.18, 0.59), P=0.0002],但 CD8+ 细胞水平的差异无统计学意义[OR =-3.12, 95% CI ( -9.02, 2.79), P >0.05]。总的来说,本研究在一定程度上反映了在辅助治疗肺癌方面,胸腺五肽能显著提高外周血中的 CD3+ 细胞水平、CD4+ 细胞水平、CD4+/CD8+ 比值。而对于治疗的有效率、CD8+ 细胞水平,差异无统计学意义。 相似文献
2.
AO Güre NK Altorki E Stockert MJ Scanlan LJ Old YT Chen 《Canadian Metallurgical Quarterly》1998,58(5):1034-1041
Supplementation with high doses of alpha-tocopherol has increased the oxidation resistance of LDL in many clinical trials. There have been only a few placebo-controlled trials in healthy persons of alpha-tocopherol doses usually contained in dietary supplements. We carried out a single-blind, placebo-controlled, randomized trial to examine the effect of 200 mg RRR-alpha-tocopheryl acetate/d on the oxidation resistance of atherogenic lipoproteins (VLDL+LDL including intermediate-density lipoproteins) in 40 smoking men. VLDL+LDL oxidation resistance was assessed as conjugated dienes after copper induction and hemin degradation after hydrogen peroxide induction. Also, the LDL total peroxyl-radical trapping antioxidant parameter (LDL TRAP) and plasma malondialdehyde were measured at baseline and after 2 mo of supplementation. Plasma RRR-alpha-tocopherol concentrations were measured at 2-h intervals for 12 h at baseline and after 2 mo of supplementation. Compared with placebo, 200-mg RRR-alpha-tocopheryl acetate supplementation elevated plasma and VLDL+LDL alpha-tocopherol concentrations, LDL TRAP, and oxidation resistance of VLDL+LDL. Plasma alpha-tocopherol increased by 88% (P < 0.0001), VLDL+LDL alpha-tocopherol increased by 90% (P < 0.0001), and LDL TRAP by 58% (P < 0.0001). The time to the start of oxidation (lag time) was prolonged by 34% when assessed with a copper-induced method and by 109% when assessed with a hemin + hydrogen peroxide-induced method; the time to maximal oxidation was prolonged by 21% (copper-induced method) in the vitamin E-supplemented group. Changes in plasma alpha-tocopherol, lipid-standardized alpha-tocopherol, and VLDL+LDL alpha-tocopherol correlated significantly with changes in LDL TRAP, lag time, and time to maximal oxidation. Differences in changes between groups in the area under the curve for plasma alpha-tocopherol were significant (P < 0.009). Our results suggest that 200 mg oral RRR-alpha-tocopheryl acetate/d had a clear effect on the in vitro oxidation of VLDL+LDL in smoking men. 相似文献
3.
NG Darenskaia AO Korotkevich SS Kuznetsova TA Nasonova 《Canadian Metallurgical Quarterly》1997,37(3):423-430
Radiation sickness manifestations have been studied in dogs exposed to electrons (electron energy 25 MeV) and gamma-neutron radiation (neutron energies of 0.37 and 1.2 MeV) in a wide dose range. Dose-response relationships have been calculated for mortality and some clinical manifestations of the intestinal and cerebral forms of radiation sickness. With regard to mortality, the highest effect has been observed for gamma-neutron radiation with a neutron energy of 1.2 MeV. For equal physical doses and for those equally effective in relation to mortality, clinical manifestations of damage are more prominent following exposure to electrons. 相似文献
4.
I. M. Kosareva M. K. Savushkina S. A. Kabakchi S. V. Korotkevich V. M. Kudryavtsev 《Atomic Energy》2006,100(2):83-89
The concepts of specific and absolute toxicity permit distinguishing in radioactive wastes belonging to different categories
the particular components that present the greatest ecological danger at different stages of their disposal in repositories.
It is shown that transuranium elements determine the toxicity parameter of high-and medium-level wastes only 350–400 years
after initial disposal. At the present stage of operation of deep repositories, the behavior of the long-lived fission products
of 90Sr and 137Cs is most important. For low-level wastes, the chemical and not the radioactive component is most dangerous.
__________
Translated from Atomnaya énergiya,Vol. 100, No. 2, pp. 86–92, February, 2006. 相似文献
5.
研制了一种新型微合金非调质钢。通过合理设计合金成分,改善熔炼脱氧过程,控制钢中氧化物的组成、分布、形状和尺寸,在研制钢中形成微细的氧化物夹杂作为晶内铁素体最有利的析出位置。通过晶内铁素体的析出细化了晶粒,提高了钢的强度与韧性。将研制的新型微合金非调质钢用于拖拉机的牵引插销是可行且有效的。 相似文献
6.
家庭网络标准及其研究计划 总被引:3,自引:2,他引:1
家庭网络处于不断发展的过程中,家电/IT行业与电信行业对于家庭网络的理解和发展思路也不一样,因此无论国际和国内都有很多从事家庭网络标准化的组织,标准不统一。中国正在制订家庭网络相关标准的组织主要有3个,分别是信息设备资源共享协同服务标准工作组(IGRS)、e家佳和中国通信标准化协会(CCSA),目前都已有了一些研究成果。为了提高中国在家庭网络领域自主创新的能力,进一步加快中国家庭网络的标准化进程,3个标准化组织应该打破行业壁垒,加强合作,实现优势互补,以合作共赢的态度研究中国自主的家庭网络标准。 相似文献
7.
8.
9.
Two residues that may ligate Ca2+ in transmembrane domain six of the plasma membrane Ca(2+)-ATPase 总被引:1,自引:0,他引:1
AO Adebayo A Enyedi AK Verma AG Filoteo JT Penniston 《Canadian Metallurgical Quarterly》1995,270(46):27812-27816
In order to identify Ca2+ ligands in the putative transmembrane domain 6 of the plasma membrane Ca2+ pump, amino acids Asn879, Met882, Asp883, and Ser887 were singly altered. Asn879, Met882, and Asp883 were chosen because the corresponding amino acids have been proposed as Ca2+ ligands in the sarcoplasmic reticulum Ca2+ pump (Clarke, D. M., Loo, T. W., and MacLennan, D. H. (1990) J. Biol. Chem. 265, 6262-6267). For the alterations, a fully active truncated version of the pump was used, because the interaction of Ca2+ with the pump could be studied without interference from calmodulin binding. The mutants at Asn and Asp did not carry out ATP-supported Ca2+ uptake and formed no acylphosphate from [gamma-32P]ATP, suggesting that, like the corresponding amino acids in the sarcoplasmic reticulum Ca2+ pump, these two are Ca2+ ligands. However, all the mutants at the position of Met882 showed some activity. Indeed, the Met882--> Ile mutant was fully active at a saturating Ca2+ concentration and only the K1/2 for Ca2+ activation was shifted slightly upward. Converting the Met to Thr (which is the corresponding residue in the sarcoplasmic reticulum Ca2+ pump) reduced the activity to 20% of the wild type, further emphasizing the differences between the two Ca2+ pumps. The mutant Ser887--> Ala was expressed in greater amounts than, and had a specific activity about 50% higher than, the wild type, indicating that this serine also could not be a Ca2+ ligand and could not replace the missing Thr at position Met882. 相似文献
10.
I. M. Kosareva M. K. Savushkina Yu. M. Volin S. A. Kabakchi O. M. Kovalevich V. D. Akhunov A. I. Borzunov S. V. D'yakov V. M. Korotkevich E. G. Kudryavtsev V. A. Lebedev 《Atomic Energy》2003,94(5):325-332
The qualitative and quantitative radiochemical composition of liquid wastes is substantiated. This makes possible further safe operation of deep waste disposal sites at the Mining-Chemical Plant and the Siberian Chemical Plant. The toxicity and temperature in a formation with the wastes removed are used as the assessment criteria, satisfaction of which guarantees that the wastes will remain localized within the assigned boundaries of the waste-disposal formation site. It is concluded that the standard limit should be imposed on the specific activity of the long-lived group of radionuclides – 90Sr and 137Cs – rather than on the total specific activity of the wastes placed in deep disposal sites. For maximum specific activity of 90Sr and 137Cs of 37 GBq/dm3 and total specific activity not exceeding 185 GBq/dm3 for buried wastes with radionuclide composition characteristic of modern radiochemical production operations, it is impossible for potentially dangerous radiation and thermochemical processes to occur in the waste-disposal formation site. The recommended limit permits reducing substantially the volume of buried wastes and therefore the region over which the wastes propagate in the deep disposal site. 相似文献