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921.
研究了碱蓬﹝Suaeda glauca (Bunge) Bunge﹞对不同盐度(质量浓度8、16和24 g·L-1NaCl)富营养化模拟海水中总氮( TN)和总磷( TP)的净化效果,并对碱蓬生长及其不同部位TN和TP的含量和积累量进行了研究。结果表明:碱蓬在质量浓度8、16和24 g·L-1 NaCl富营养化模拟海水中均生长良好。随处理时间的延长,种植碱蓬后不同盐度富营养化模拟海水中TN和TP浓度均逐渐降低,TN和TP去除率均逐渐升高,其中在质量浓度16 g·L-1 NaCl富营养化模拟海水中TN和TP去除率最高。处理25 d,在质量浓度16 g·L-1 NaCl富营养化模拟海水中碱蓬单株鲜质量、单株干质量和株高的增量以及平均须根长均最大,单株总干质量最高,均显著高于其他2个处理组;质量浓度16 g·L-1 NaCl富营养化模拟海水中碱蓬单株叶、茎和根中的TN和TP积累量明显高于其他2个处理组,而单株种子中的TN和TP积累量则随着NaCl质量浓度提高而降低。研究结果显示:作为在滨海盐渍化土壤中生长的一年生优势物种,碱蓬可以有效地对有一定盐度的富营养化水体进行生物修复,具有对滩涂养殖废水进行生物改良和修复的潜力。  相似文献   
922.
采用正交试验法,对艾叶总黄酮索氏提取工艺进行考察,确定艾叶总黄酮最优提取工艺。结果发现,以总黄酮得率作为考察指标,艾叶中总黄酮的最佳提取条件为:料液比为1∶35,浸提温度为80℃,浸提时间为3h,乙醇体积分数为70%,艾叶总黄酮得率高达3.85%。  相似文献   
923.
1,3,4-Thiadiazole was explored as a more polar, heterocyclic replacement for the phenyl ring in the 3-arylpropionic acid pharmacophore present in the majority of GPR40 agonists. Out of 13 compounds synthesized using a flexible, three-step protocol (involving no chromatographic purification), four compounds were confirmed to activate the target in micromolar concentration range. While the potency of the series should be subject of further optimization, the remarkable aqueous solubility and microsomal stability observed for the lead compound (8g) apparently attests to this new scaffold’s high promise in the GPR40 agonist field.  相似文献   
924.
Several species of ornamental flowering plants were evaluated regarding their phytoremediation ability for the cleanup of oil-contaminated soil in Japanese environmental conditions. Thirty-three species of plants were grown in oil-contaminated soil, and Mimosa, Zinnia, Gazania, and cypress vine were selected for further assessment on the basis of their favorable initial growth. No significant difference was observed in the above-ground and under-ground dry matter weight of Gazania 180 days after sowing between contaminated and non-contaminated plots. However, the other 3 species of plants died by the 180th day, indicating that Gazania has an especially strong tolerance for oil-contaminated soil. The total petroleum hydrocarbon concentration of the soils in which the 4 species of plants were grown decreased by 45–49% by the 180th day. Compared to an irrigated plot, the dehydrogenase activity of the contaminated soil also increased significantly, indicating a phytoremediation effect by the 4 tested plants. Mimosa, Zinnia, and cypress vine all died by the 180th day after seeding, but the roots themselves became a source of nutrients for the soil microorganisms, which led to a phytoremediation effect by increase in the oil degradation activity. It has been indicated that Gazania is most appropriate for phytoremediation of oil-contaminated soil.  相似文献   
925.
以凉水国家自然保护区激光雷达数据为基础,建立数字高程模型,提取基本地形属性如坡度、坡向和复合地形属性湿度指数和相对径流强度指数等,在成土因素学说基础上,对全氮含量(TN)进行地理加权回归建模(GWR),同时运用反距离加权(IDW)、普通克里格(OK)和泛克里格(UK)对TN进行空间插值.结果表明: 对于研究区TN的预测,GWR模型预测精度(77.4%)高于其他3种空间插值方法,IDW预测精度(69.4%)高于OK(63.5%)和UK(60.6%)的预测精度.利用GWR模型预测研究区域土壤TN平均达到4.82 g·kg-1;在高海拔、地形湿度大以及相对径流强的区域,土壤TN相对较高.对预测结果进行探讨发现,不同坡位、坡向的土壤TN也存在一定差异.因此,基于地形属性的局域模型是土壤属性空间分布预测的更为有效的方法.  相似文献   
926.
选择4种湿地植物菖蒲、香蒲、浮萍和金鱼藻,研究单一及组合湿地植物对高浓度污水(污水处理厂进水)、低浓度污水(污水处理厂出水)中营养物质的去除效果.结果表明: 水体中总氮(TN)、总磷(TP)、化学需氧量(COD)浓度呈现试验前期快速下降,后期缓慢下降的趋势,表明湿地植物能有效净化污水中的TN、TP、COD,但不同湿地植物及湿地植物组合的净化效果存在差异.多种湿地植物组合比单种湿地植物对TN的净化作用强,其中香蒲+浮萍+金鱼藻对TN的净化效果最佳;高浓度污水中,单种挺水植物对TP的净化效果较好,低浓度污水中,则是多种湿地植物组合对TP的去除率较高;高浓度污水中,湿地植物对COD的去除率为85.1%~96.0%,其中菖蒲、香蒲去除效果最佳,低浓度污水中,湿地植物对COD去除率为76.9%~94.8%,以菖蒲+浮萍+金鱼藻去除效果最好.总体看来,湿地植物对高浓度污水中TN、TP、COD的净化效果好于低浓度污水,两种水体的pH都得到改善.  相似文献   
927.
Battery electric motorcycles offer the potential to reduce greenhouse gas emissions and fossil fuel consumption in road transportation, but result in problem shifting when considering potential environmental impacts during vehicle production and disposal. This study evaluates the life cycle environmental impacts of implementing lithium‐ion and lead‐acid battery electric motorcycles in Thailand's motorcycle fleet to meet the government's motorcycle energy reduction target of 2,791 kilotonnes oil equivalent, compared to conventional motorcycles. A stock‐turnover model is used to determine the market growth of electric motorcycles on the fleet from 2015 to 2030 to meet the energy reduction target. The total costs of ownership of each motorcycle are analyzed on a single vehicle basis to compare the cost benefits. The results of the study reveal that the environmental performance of an electric motorcycle fleet is sensitive to variations in use‐phase energy consumption, the electricity mix consumed, and battery disposal scenarios. Realization of Thailand's Power Development Plan can reduce total impacts of the electric motorcycle fleet to global warming by 6% to 10%. It is crucial that batteries from electric motorcycles are recycled to avoid 98% of impacts to toxicity. Lead‐acid battery electric motorcycles are a more affordable option for consumers in Thailand compared to conventional motorcycles and lithium‐ion battery electric motorcycles. Recommendations are made to improve the environmental performance of electric motorcycle implementation strategies in Thailand.  相似文献   
928.
This study investigates the dynamic linkages between biofuels production and sustainable indicators in the panel of 17 developed and developing countries, over the period of 2000–2012. The study emphasized the role of biofuels production in the sustainable development of the region. For this purpose, the study utilized four main sustainable indicators including carbon dioxide emissions, energy intensity, renewable energy generation, and total population that have a significant impact on the biofuels production. The study used dynamic heterogeneous panel econometric technique – Generalized Method of Moments and found that carbon dioxide emissions increase along with the increase in biofuels production. Therefore, the caution should be applied when burning the biofuels during the production process. In addition, renewable electricity generation also increases the biofuels production in the region. The results of robust least square regression confirmed that all of the sustainable indicators have a significant association with the biofuels production, as total primary energy consumption increases the biofuels production, while total population significantly decreases the biofuels production in the region. The results derived to the conclusion that for sustainable development in the region, the policymakers should have to formulate carbon free policies that coupled with the renewable energy sources for emphasizing the life cycle of bioenergy during the production process.  相似文献   
929.
目的:探讨平卧位直接前方入路(DAA)与侧卧位直接外侧入路(DLA)对行初次全髋关节置换术(THA)患者髋关节功能、平衡功能和步态参数的影响。方法:选取2018年2月~2019年10月期间我院收治的初次THA患者97例,根据入路方式的不同随机分为A组(n=47)和B组(n=50),A组行侧卧位DLA,B组行平卧位DAA,比较两组髋关节功能、影像学参数、平衡功能和步态参数,记录两组术后并发症发生率。结果:术后1周、1个月、3个月及6个月两组髋关节Harris评分(HHS)、Berg平衡量表评分(BBS)依次升高,且B组高于A组(P0.05)。B组手术时间长于A组,术中出血量少于A组,切口长度、初次下床行走时间短于A组(P0.05)。术后3个月、6个月两组步频、步速、步长依次升高,且B组高于A组(P0.05)。两组并发症发生率对比,组间比较未见统计学差异(P0.05)。两组术后6个月髋臼假体外展角、前倾角对比,组间比较无显著差异(P0.05)。结论:与侧卧位DLA相比,初次THA患者行平卧位DAA可获得与其相当的手术效果,同时能更好地改善患者髋关节功能、平衡功能和步态,且安全性有保障。  相似文献   
930.
Hepatic function is of great concern in metabolic and immunological homeostasis. Traditionally, medical management to liver damage may benefit from phytomedicine, such as Chinese herbs. In southern China, Polygonum perfoliatum L can contribute to alleviating pathological symptoms of liver disease, such as hepatitis. However, bioactive compounds of hepatoprotection in this herb are still less to be investigated. In this study, clinical data of patients with drug-induced liver injury were collected on the basis of serological analyses. In addition, we extracted and identified total flavonoids from Polygonum perfoliatum L (TFPPL) before implementing biochemical experiments in vivo. In human data, the blood contents of liver function enzymes were visibly elevated, and the percentage of immune cells were abnormally changed. The data from the animal study showed that TFPPL-treated carbon tetrachloride-exposed mice resulted in reduced absolute liver mass and lowered blood levels of liver functional enzymes (alanine transaminase and aspartate transaminase). In enzyme-linked immunosorbent assay, the comparable data indicated that serological tumor necrosis factor α (TNF-α), interleukin 6, and heat shock protein 90 (Hsp90) contents were reduced in TFPPL-treated mice. In histopathological observations, TFPPL-treated mice exhibited reduced hepatocellular Hsp90, TNF-α, nuclear factor κ-light-chain-enhancer of activated B cells-p65 positive cells, and lowered Bax and caspase-3-labeled cells in the livers. Further, intrasplenic integrin β1, 5′-nucleotidase, and antigen KI-67 positive cells were increased after TFPPL treatments. Taken together, our present findings demonstrate that herb-extracted TFPPL exert potential hepatoprotective activities against chemical-induced liver damage in mice, possibly through the pharmacological mechanisms of inhibiting inflammatory stress and apoptosis, inactivating Hsp90 bioactivity in the liver, and improving splenic immunocompetence.  相似文献   
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