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141.
Albert Maim-Barcel Lucía Martín-Saiz Jos A. Fernndez Karim Prez-Romero Santiago Garfias-Arjona Mnica Lara-Almúnia Javier Pirola-Lopetegui Joan Bestard-Escalas Gwendolyn Barcel-Coblijn 《International journal of molecular sciences》2022,23(6)
Glioblastoma (GBM) represents one of the deadliest tumors owing to a lack of effective treatments. The adverse outcomes are worsened by high rates of treatment discontinuation, caused by the severe side effects of temozolomide (TMZ), the reference treatment. Therefore, understanding TMZ’s effects on GBM and healthy brain tissue could reveal new approaches to address chemotherapy side effects. In this context, we have previously demonstrated the membrane lipidome is highly cell type-specific and very sensitive to pathophysiological states. However, little remains known as to how membrane lipids participate in GBM onset and progression. Hence, we employed an ex vivo model to assess the impact of TMZ treatment on healthy and GBM lipidome, which was established through imaging mass spectrometry techniques. This approach revealed that bioactive lipid metabolic hubs (phosphatidylinositol and phosphatidylethanolamine plasmalogen species) were altered in healthy brain tissue treated with TMZ. To better understand these changes, we interrogated RNA expression and DNA methylation datasets of the Cancer Genome Atlas database. The results enabled GBM subtypes and patient survival to be linked with the expression of enzymes accounting for the observed lipidome, thus proving that exploring the lipid changes could reveal promising therapeutic approaches for GBM, and ways to ameliorate TMZ side effects. 相似文献
142.
This paper employs societal lifetime cost for evaluating hydrogen fuel cell vehicles (FCVs) from a societal welfare perspective as compared to conventional gasoline vehicles. We employ a learning-curve model for fuel-cell system cost estimates over time. The delivered hydrogen fuel cost is estimated using the UC Davis SSCHISM hydrogen supply pathway model, and most vehicle costs are estimated using the Advanced Vehicle Cost and Energy-Use Model (AVCEM). To estimate external costs, we use AVCEM and the Lifecycle Emissions Model (LEM). We examine hydrogen transition costs for a range of market penetration rates, externality evaluations, technology assumptions, and oil prices. Our results show that although the cost difference between FCVs and gasoline vehicles is initially very large, FCVs eventually become lifetime cost competitive with gasoline vehicles as their production volume increases, even without accounting for externalities. High valuation of externalities and high oil price could reduce the buy-down cost (the cumulative investment needed to bring hydrogen FCVs to lifetime cost parity with gasoline vehicles) by $10 billion relative to our reference case. 相似文献
143.
C.P. Ferris P.J. Purcell A.W. Gordon T. Larsen M. Vestergaard 《Journal of dairy science》2018,101(8):7258-7273
This 2 × 2 factorial design experiment was conducted to compare the performance of spring-calving Holstein dairy cows (HOL, n = 34) with Swedish Red × Jersey/Holstein crossbred (SR × J/HOL, n = 34) dairy cows within low and medium concentrate input grassland-based dairy systems. The experiment commenced when cows calved and encompassed 1 full lactation. Cows were offered diets containing grass silage and concentrates [70:30 dry matter (DM) ratio, and 40:60 DM ratio, for low and medium, respectively] until turnout, grazed grass plus either 1.0 or 4.0 kg of concentrate/d during the grazing period (low and medium, respectively), and grass silage and concentrates (85:15 DM ratio, and 70:30 DM ratio, for low and medium, respectively) from rehousing and until drying off. No significant genotype × system interactions were present for any of the feed intake or full-lactation milk production data examined. Full-lactation concentrate DM intakes were 769 and 1,902 kg/cow for the low and medium systems, respectively, whereas HOL cows had a higher total DM intake than SR × J/HOL cows in early lactation, but not in late lactation. Although HOL cows had a higher lactation milk yield than SR × J/HOL cows, the latter produced milk with a higher fat and protein content, and thus fat plus protein yield was unaffected by genotype. Milk produced by the SR × J/HOL cows had a higher degree of saturation of fatty acids than milk produced by the HOL cows, and the somatic cell score of milk produced by the former was also higher. Throughout the lactation, HOL cows were on average 30 kg heavier than SR × J/HOL cows, whereas the SR × J/HOL cows had a higher body condition score than the HOL cows. Holstein cows had a higher incidence of mastitis and ovarian dysfunction that SR × J/HOL cows. 相似文献
144.
A novel thick film technology has been developed for the manufacture of electric heating elements from partially oxidised Ni–Cr–Fe alloy powder. The sprayed films were a mixture of metallic alloys and Ni-based oxides. Electron microscopy and analysis were used to monitor the transformations in the films during subsequent heat treatment. In particular, it was found that homogeneous grains of Cr- and Fe-doped Ni-based oxides transformed into NiO grains containing numerous Ni-, Cr- and Fe-rich spinel particles with a typical size of 40 nm. 相似文献
145.
Injured peripheral nerves but not central nerves have the capacity to regenerate and reinnervate their target organs. After the two most severe peripheral nerve injuries of six types, crush and transection injuries, nerve fibers distal to the injury site undergo Wallerian degeneration. The denervated Schwann cells (SCs) proliferate, elongate and line the endoneurial tubes to guide and support regenerating axons. The axons emerge from the stump of the viable nerve attached to the neuronal soma. The SCs downregulate myelin-associated genes and concurrently, upregulate growth-associated genes that include neurotrophic factors as do the injured neurons. However, the gene expression is transient and progressively fails to support axon regeneration within the SC-containing endoneurial tubes. Moreover, despite some preference of regenerating motor and sensory axons to “find” their appropriate pathways, the axons fail to enter their original endoneurial tubes and to reinnervate original target organs, obstacles to functional recovery that confront nerve surgeons. Several surgical manipulations in clinical use, including nerve and tendon transfers, the potential for brief low-frequency electrical stimulation proximal to nerve repair, and local FK506 application to accelerate axon outgrowth, are encouraging as is the continuing research to elucidate the molecular basis of nerve regeneration. 相似文献
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149.
This paper examines empirical relationships between the geometrical parameters of the spinning triangle and the quality parameters of ring spun yarns. For this purpose, controlled variations in the geometry of the spinning triangle were induced using two existing modifications in the ring spinning process and by varying the yarn twist level. The geometrical parameters of the spinning triangle were measured using the clear rubber roller combined with digital image processing techniques as described in the first part of this study. The yarn quality parameters measured included yarn hairiness, strength, elongation and evenness. Yarn hairiness showed more noticeable sensitivity towards the physical shape of the spinning triangle than yarn tenacity, while yarn evenness and elongation were not significantly influenced by changes in spinning triangle geometry. 相似文献
150.
Tomás Lafarga Silvia Villaró Gloria Bobo Joan Simó Ingrid Aguiló-Aguayo 《International Journal of Food Science & Technology》2019,54(5):1816-1823
The aim of this study was to evaluate the bioaccessibility of polyphenols and antioxidant activity in cooked pulses and to study the effect of cooking on their total phenolic content (TPC) and antioxidant capacity. Cooked faba beans showed the highest TPC, followed by soybeans and lentils or peas. TPC ranged from 10.4 ± 0.2 to 52.9 ± 0.3 mg/100 g and was positively correlated with antioxidant activity. Cooking resulted in increased TPC and antioxidant activity of the methanolic extracts, caused by cell disruption and improved extraction of polyphenols. Although polyphenols were lost in the cooking water, boiled legumes had more polyphenols than those resulting cooking broths. In vitro gastrointestinal digestion resulted in increased TPC and antioxidant capacity of the extracts. Soybeans showed the highest amount of bioaccessible polyphenols. The release of phenolics from cooked legumes was mainly achieved during the intestinal phase. Literature data may underestimate the TPC and antioxidant capacity of pulses. 相似文献