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91.
The objective of this present research is to use agricultural residues as a source of energy for heating greenhouses during winter seasons and sequestrating soil carbon dioxide through adding biochar to the soil media. To fulfill the objective of the research work, summer squash was transplanted in a constructed greenhouse and heated using an attached biomass-burning system. The performance of the attached biomass-burning system was experimentally studied under different agricultural residues (corn stalks, cotton stalks and okra stalks), heating fluids (water and oil) and air fan operating periods (10, 15 and 20 min/h). Results indicated that the biomass-burning system allowed increasing temperature and relative humidity inside the greenhouse up to 27.2 and 80 %, respectively. The maximum biomass-burning system efficiency of 81 % was achieved with the use of okra stalks as a source of energy and oil as a heating fluid side by side with adjusting the suction fan operating period at 15 min/h. Adding bio-charcoal to the soil media, enhanced the soil carbon, resulting in a total fresh yield of 3.7 and 2.9 kg/pot with a total number of leaves per plant of 55 and 47 leaves under conditions of with and without charcoal addition, respectively.  相似文献   
92.
Despite much research, gaps remain in knowledge about the potential health effects of exposure to radiofrequency (RF) fields. This study investigated the effects of early‐life exposure to pulsed long term evolution (LTE) 1,846 MHz downlink signals on innate mouse behavior. Animals were exposed for 30 min/day, 5 days/week at a whole‐body average specific energy absorption rate (SAR) of 0.5 or 1 W/kg from late pregnancy (gestation day 13.5) to weaning (postnatal day 21). A behavioral tracking system measured locomotor, drinking, and feeding behavior in the home cage from 12 to 28 weeks of age. The exposure caused significant effects on both appetitive behaviors and activity of offspring that depended on the SAR. Compared with sham‐exposed controls, exposure at 0.5 W/kg significantly decreased drinking frequency (P ≤ 0.000) and significantly decreased distance moved (P ≤ 0.001). In contrast, exposure at 1 W/kg significantly increased drinking frequency (P ≤ 0.001) and significantly increased moving duration (P ≤ 0.005). In the absence of other plausible explanations, it is concluded that repeated exposure to low‐level RF fields in early life may have a persistent and long‐term effect on adult behavior. Bioelectromagnetics. 2019;40:498–511. © 2019 The Authors. Bioelectromagnetics Published by Wiley Periodicals, Inc.  相似文献   
93.
94.
白鹤(Grus leucogeranus)是IUCN极危物种,全球仅存3 500~4 000只,其中约98%的个体在鄱阳湖越冬。以前白鹤在鄱阳湖主要在浅水生境挖掘苦草(Vallisneria spp.)的冬芽为食。然而,近年来农业用地已成为白鹤的重要觅食地。目前对于白鹤在农业用地的食物组成尚不清楚。本研究采用粪便显微镜检法对2017年11月至2018年4月采集的70份白鹤粪便样品进行分析。结果表明,白鹤的食物来源于10科15种植物,其中,水稻(Oryza sativa)、莲藕(Nelumbo nucifera)和紫云英(Astragalus sinicus)为最主要的食物,这3种植物在检测到的食物中的相对密度分别为34.34%、22.99%和10.61%,而白鹤的传统食物苦草冬芽所占的比例极低(2.05%)。由此可见,白鹤的食物组成已经发生变化,农作物已成为白鹤的重要食物来源。白鹤在农业用地中觅食使该物种的保护面临一系列问题,尤其是高强度的人为干扰,对此,提出了相应的保护措施,希望为白鹤提供安全、稳定的觅食环境。  相似文献   
95.
Growing evidence has shown that pulsed electromagnetic fields (PEMF) can modulate bone metabolism in vivo and regulate the activities of osteoblasts and osteoclasts in vitro. Osteocytes, accounting for 95% of bone cells, act as the major mechanosensors in bone for transducing external mechanical signals and producing cytokines to regulate osteoblastic and osteoclastic activities. Targeting osteocytic signaling pathways is becoming an emerging therapeutic strategy for bone diseases. We herein systematically investigated the changes of osteocyte behaviors, functions, and its regulation on osteoclastogenesis in response to PEMF. The osteocyte-like MLO-Y4 cells were exposed to 15 Hz PEMF stimulation with different intensities (0, 5, and 30 Gauss [G]) for 2 hr. We found that the cell apoptosis and cytoskeleton organization of osteocytes were regulated by PEMF with an intensity-dependent manner. Moreover, PEMF exposure with 5 G significantly inhibited apoptosis-related gene expression and also suppressed the gene and protein expression of the receptor activator of nuclear factor κB ligand/osteoprotegerin (RANKL/OPG) ratio in MLO-Y4 cells. The formation, maturation, and osteoclastic bone-resorption capability of in vitro osteoclasts were significantly suppressed after treated with the conditioned medium from PEMF-exposed (5 G) osteocytes. Our results also revealed that the inhibition of osteoclastic formation, maturation, and bone-resorption capability induced by the conditioned medium from 5 G PEMF-exposed osteocytes was significantly attenuated after abrogating primary cilia in osteocytes using the polaris siRNA transfection. Together, our findings highlight that PEMF with 5 G can inhibit cellular apoptosis, modulate cytoskeletal distribution, and decrease RANKL/OPG expression in osteocytes, and also inhibit osteocyte-mediated osteoclastogenesis, which requires the existence of primary cilia in osteocytes. This study enriches our basic knowledge for further understanding the biological behaviors of osteocytes and is also helpful for providing a more comprehensive mechanistic understanding of the effect of electromagnetic stimulation on bone and relevant skeletal diseases (e.g., bone fracture and osteoporosis).  相似文献   
96.
Electromagnetic fields (EMFs) are reported to interfere with chemical reactions involving free radical production. Coenzyme Q10 (CoQ10) is a strong antioxidant with some neuroprotective activities. The purpose of this study was to examine and compare the neuroprotective effects of EMF and CoQ10 in a mouse model of hippocampal injury. Hippocampal injury was induced in mature female mice (25–30 g), using an intraperitoneal injection of trimethyltin hydroxide (TMT; 2.5 mg/kg). The experimental groups were exposed to EMF at a frequency of 50 Hz and intensity of 5.9 mT for 7 hr daily over 1 week or treated with CoQ10 (10 mg/kg) for 2 weeks following TMT injection. A Morris water maze apparatus was used to assess learning and spatial memory. Nissl staining and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) tests were also performed for the histopathological analysis of the hippocampus. Antiapoptotic genes were studied, using the Western blot technique. The water maze test showed memory improvement following treatment with CoQ10 and coadministration of CoQ10 + EMF. The Nissl staining and TUNEL tests indicated a decline in necrotic and apoptotic cell count following treatment with CoQ10 and coadministration of CoQ10 + EMF. The Western blot study indicated the upregulation of antiapoptotic genes in treatment with CoQ10, as well as coadministration. Also, treatment with EMF had no significant effects on reducing damage induced by TMT in the hippocampus. According to the results, EMF had no significant neuroprotective effects in comparison with CoQ10 on hippocampal injury in mice. Nevertheless, coadministration of EMF and CoQ10 could improve the neuroprotective effects of CoQ10.  相似文献   
97.
The owlet moths (Lepidoptera: Noctuidae) Anicla infecta (Ochsenheimer 1816), Elaphria agrotina (Guenée 1852) and Spodoptera frugiperda (J.E. Smith 1797) occur in the entire American continent. These polyphagous moths have a preference for grasses, and have different biological habits. In this study, the populations of these three species were evaluated monthly with light traps in the Brazilian Savannah, ranging a span of four crop seasons (from July, 2013 to June, 2017). The population data were analyzed and correlated with the meteorological variables: maximum temperature, minimum temperature, relative humidity and precipitation. A total of 4719 individuals were collected in the following percentages: A. infecta (n = 459; 9.73%), E. agrotina (n = 1809; 38.33%) and S. frugiperda (n = 2451; (51.94%). The abundance of all species went down from the first crop season (2013/2014) to the third (2015/2016). In the fourth crop season (2016/2017), the populations of A. infecta and E. agrotina stabilized, but the abundance of S. frugiperda experienced further decrease. The numbers of individuals of three species declined when precipitation was much above (crop season 2014/2015) and below (crop season 2015/2016) than expected by the climatological normal. There were significant, but different degrees of correlation, between the meteorological factors and the ONI index (Oceanic Niño Index - indicator for monitoring El Niño-Southern Oscillation or “ENSO”) with respect to monthly population variations. The results are discussed in accordance with principles of the Integrated Pest Management (IPM) in mind, given the continental distribution and agricultural importance of the three owlet moth species studied.  相似文献   
98.
Exposure to electromagnetic fields is considered as a potential hazard for biological systems. The objective of our investigation is the study of probable consequences of radiofrequency electromagnetic fields from Wi-Fi router devices on the short-term memory, and attention's levels. A population consisting of 312 female college students (14 to 17 years old) was elected by cluster random sampling. Teenagers were divided into two groups of control group (Wi-Fi nonusers; n = 138), and experiment group (Wi-Fi users; n = 174). Both groups have been examined using short-term memory tests; selective attention, and also divided attention tests. According to the results, there was no significant difference between using Wi-Fi router devices on levels of selective attentions and short-term memory of the sample students with the control group. However, analyses revealed that there is a significant correlation between the use of Wi-Fi routers and declining levels of divided attentions. Our investigation has demonstrated the adverse consequences of 2.4-2.48 GHz radiofrequency electromagnetic fields of Wi-Fi router devices on divided attention levels of female university students that should be mentioned as a technological risk factor and taken into account by healthcare organizations.  相似文献   
99.
The permeabilization and gene transfer phenomena in terms of the effect of electric field and cell parameters are reviewed in this paper. Electropermeabilization designates the use of short high‐voltage pulses to overcome the barrier of the cell membrane. A position‐dependent modulation of the membrane potential difference is induced, leading to a transient and reversible local membrane alteration. The electro‐induced permeabilization is long lived. A free exchange of hydrophilic molecules takes place across the membrane. The fraction of the cell surface which is competent for exchange is a function of the field intensity. The level of local exchange is strongly controlled by the pulse duration. This permeabilized state can be used to load cells with a variety of different molecules, either through simple diffusion in the case of small molecules, or through a multi‐step process as is the case for DNA transfer involving the electrophoretically driven association of the macromolecule with the destabilized membrane and its subsequent passage. Electropermeabilization is now in use for the delivery of a large variety of molecules: from ions to drugs, dyes, tracers, antibodies, oligonucleotides, RNA and DNA. While most studies are performed in vitro in cells in culture, an increasing number of data are obtained in vivo on tissues. However, membrane molecular and cell metabolic changes remain for the most part poorly understood. Therefore it is of great importance to elucidate the underlying phenomena both for the in vitro use of the method in terms of efficiency but also for the in vivo use of the method in terms of security.  相似文献   
100.
The aim of this work was to study the effect of a high voltage pulsed electric field (PEF) on the inactivation of E. coli in cranberry juice to achieve the regulatory requirement of a 5‐log reduction in the microbial count. PEF processing involved the application of high voltage pulses to liquid or semi‐solid materials, placed between two electrodes at ambient, sub‐ambient, or supra‐ambient temperature. In this work, cranberry juice, inoculated with E. coli was subjected to 60 pulses in the voltage range of 5 to 40 kV/cm. The experiments were carried out at 20 °C. The temperature rise was less than 2 °C at the average treatment time of 80 s. PEF is an emerging non‐thermal technology for food preservation that retains the natural taste of food. It has mainly been applied to improve the shelf life of such foods as milk, liquid eggs and fruit juices.  相似文献   
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