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11.
Summary Suspended particulate matter (SPM) concentrations were measured in about 100 homes in the city of Arnhem, The Netherlands. Most homes were sampled for 2 months continuously. Monthly average SPM concentrations ranged from 20–570 g/m3. From 26 houses, smoking data were gathered at a later date. A clear relationship was found between SPM concentrations and number of smokers in the home.  相似文献   
12.
提出环境污染健康损害判定工作程序及步骤,给出已知污染物或未知污染物造成健康损害判定工作框图,并提出健康损害判定:①必须经环境保护主管部门进行资质认定的环境污染健康损害判定机构承担;②具有健康损害判定资质的机构应建立相应专家组;③健康损害判定专家组按相关标准根据医学诊断、环境证据及因果关系进行健康损害判定。  相似文献   
13.
Environmental pollution has particular implications for the whole geosystem and increases the global risk to human and ecological health. In this regard, investigations were carried out on soil samples to perform the quality status assessment by determining: pH, texture, structure and metal concentration, as well as carrying out an assessment of anthropogenic activity by determining pollution indices: Cf (contamination factor), Cd (degree of contamination), PLI (pollution load index), Er (ecological risk index) and PERI (potential ecological risk index). Analyses on soil samples showed high concentrations of metals (Cu: 113–2996 mg kg−1; Pb: 665–5466 mg kg−1; Cr: 40–187 mg kg−1; Ni: 221–1708 mg kg−1). The metal extraction experiments were carried out by bioleaching using Thiobacillus ferrooxidans, microorganisms at different amounts of bioleaching solution (20 mL and 40 mL 9K medium) and a stirring time of up to 12 h. The results on the degree of contamination, pollution loading index PLI (2.03–57.23) and potential ecological risk index PERI (165–2298) indicate that the soils in the studied area have a very high degree of pollution. The decontamination procedure by bioleaching showed a decrease, but at the end of the test (12 h), the followed indices indicate high values, suggesting that bioleaching should continue. The depollution yield after 12 h of treatment is, however, encouraging: Cu 29–76%, Pb: 10–32%, Cr: 39–72% and Ni 44–68%. The use of yield–time correlation equations allows the identification of the optimal exposure time on the bioleaching extraction process to obtain optimal results. The aim of the research is to determine the soil quality, soil environmental risk, extraction of metals from polluted soils by bioleaching and to identify influencing factors in achieving high remediation yields.  相似文献   
14.
Recently, photocatalysis has been demonstrated as a solid approach for efficient wastewater cleaning. Using natural materials as photocatalysts means a promising solution to develop green catalysts for environmental purposes. This work aimed to study the suitability of a natural volcanic material (La Gomera, Canary Islands, Spain) as a photocatalytic material for the degradation of pollutants in wastewater with solar energy. After analysing the properties of the natural material (BET surface 0.188 m2/g and band-gap of 3 eV), the photocatalytic activity was evaluated at laboratory and pilot plant scale for the degradation of methylene blue (MB) in water (50 mg L−1), at 20 °C, during a period of 4 h, under UV/Vis light and solar irradiation. Photolytic and adsorption studies were developed to distinguish the photocatalytic contribution to the wastewater decontamination process by photocatalysis. Our results enable us to determine the viability of black sand as a photocatalytic material activated by solar irradiation (photodegradation of MB up to 100% by using solar energy), developing a natural and green photocatalytic system with significantly high potential for application in a sustainable wastewater cleaning process.  相似文献   
15.
本文运用描述流行病学方法初步探讨了上海市不同空气污染条件下8个社区的中风死亡率(1978~1987)的时空分布及其与室内外空气污染的关系.结果表明中风死亡率与大气污染水平无明显关系,但发现在相同大气污染条件下,燃煤社区的中风死亡率明显高于燃气社区,提示燃煤型室内空气污染可能是中风的重要诱发因素之一.  相似文献   
16.
Realizing the green recycling of sludge is an important link to effectively solve the problem of sludge disposal. In this paper, sewage sludge (SS) and rice husk (RH) were utilized as raw materials in preparing novel ceramsite (SRC) for the treatment of lead-containing wastewater, and its adsorption mechanism was explored. The results showed that the optimal preparation conditions were 40% RH + 60% SS mixture, a sintering temperature of 1190 °C, and a sintering time of 20 min. The basic properties of SRC met Chinese artificial ceramsite filter material standards for water treatment (CJ/T 299-2008). Under optimum adsorption conditions (pH = 6, 1 g/L SRC dosage, 20 mg/L Pb(NO)3 concentration, 18 h), the removal rate of Pb2+ reached 94.7%, and the equilibrium adsorption capacity was 18.94 mg/g. The adsorption process was more consistent with the pseudo-second-order kinetic model and the Langmuir isotherm model, indicating that the adsorption process was dominated by chemisorption. Thermodynamic parameters (ΔH0 > 0, ΔG0 < 0, ΔS0 > 0) indicated that the adsorption reaction was spontaneous and endothermic. The possible adsorption mechanisms are as follows: (1) SRC is rich in layered mesoporous structure, which provides sufficient reaction sites for Pb adsorption; (2) the sintered lawsonite and muscovite can strongly attract Pb and then form a new phase (Pb10[Si2O7]3(OH)2); (3) Pb2+ can bond with the Si–O- bond in aluminosilicates, and the introduction of Pb elevates the degree of polymerization of aluminosilicates in turn, indicating that the adsorption process is stable.  相似文献   
17.
Sedimentation is a naturally occurring process of allowing particles in water bodies to settle out of the suspension under a gravity effect. In this study, the sediments of the Drava River were fully investigated to determine the heavy metal concentrations along the river and their potential reuse in the construction sector. Naturally dehydrated sediments from the Drava River were tested as an additive for the production of fired bricks. The dredged sediments were used as a substitute for natural brick clay in amounts up to 50% by weight, and it was confirmed that up to 20% by weight of the added sediment could be used directly in the process without critically affecting performance. Finally, the naturally dehydrated sediments were also evaluated for their use as a filling material in the construction of levees. The natural moisture content of the dehydrated sediment was too high for it to be used without additives, so quicklime was added as an inorganic binder. The test results showed an improvement in the geotechnical properties of the material to such an extent that it is suitable as a filling material for levees.  相似文献   
18.
More and more reports have pointed out that rotenone, as an insecticide, has high neurotoxicity and reproductive toxicity to livestock and mammals. As a highly physiological correlation system of internal organs, quasi-organs have great potential in the fields of drug toxicity and efficacy test, toxicology research, developmental biology and so on. In this study, brain organs (mBOs) derived from mouse neural stem cells were used to investigate the effects of rotenone on the physiological activity and epigenetic modification of mBOs. At the same time, Rotenone could significantly stimulate the increase of the concentration of LPO, lactic acid and hydroxyl radical in mBOs, and inhibit the expression of neuronal marker Tuj1, CHAT, PAX6 and so on. Further analysis showed that Rotenonem could induce mitochondrial damage in mBOs. The results of qPCR and Western blot showed that Rotenone could up-regulate the expressions of ferroptosis promoting protein p53, Cox2 and so on, while inhibit the expressions of negative regulatory protein of ferroptosis GPX4, FTH1, SLC7A11. In addition, the results of RRBS-Seq sequencing showed that the methylation modification at DMR level in Rotenone-treated mBOs group was significantly higher than that in Ctrl group. The results of KEGG analysis showed that compared with Ctrl, the genes with hypermethylation of promoter and Genebody in Rotenone-treated mBOs were mainly located in the Neuro active ligand-receptor interaction signal transduction pathway. In summary, rotenone can significantly lead to abnormal methylation of mouse brain organs, and lead to the loss of normal physiological function of neurons by inducing ferroptosis.  相似文献   
19.
Measuring ammonia from the environmental air is a sensitive and prioritized issue due to its harmful effects on humans, ecosystems, and climate. Ammonia is an environmental pollutant that has an important role in forming secondary inorganic aerosols, the main component of fine particulate matter concentrations in the urban atmosphere. Through this study, we present a gas analyzer that utilizes the technique of laser photoacoustic spectroscopy to measure ammonia concentration in three different sites located in Magurele, (44°20′58″ N 26°01′47″ E, 93 m altitude), Romania, from March to August 2021 at the breathing level of 1.5 m above ground. The ammonia concentrations from the ambient air were elevated in summer (mean of 46.03 ± 8.05 ppb (parts per billion)) compared to those measured in spring (18.62 ± 2.92 ppb), which means that atmospheric temperature affects ammonia concentrations. The highest mean ammonia concentrations occurred in August, with an ammonia concentration level of 100.68 ± 11.12 ppb, and the low mean ammonia concentrations occurred in March, with an ammonia level concentration of 0.161 ± 0.03 ppb. The results confirm that meteorological characteristics (i.e., temperature) and motor vehicles are major contributors to the elevated ammonia levels during the monitoring period.  相似文献   
20.
  目的  分析山东省不同农村地区的环境卫生与疾病的现状及区域变化特点,为制定相应的干预和控制措施提供依据。  方法  2015 — 2017年,结合山东省地理位置,按东部、中部、西部进行分层,共选取25个县(市),采用抽签的方法在每县随机抽取20个自然村,每自然村随机抽取5户家庭,共500个村2 500户,采用统一调查表,通过查阅资料、现场调查、访谈、土壤样品采集、实验室检测等方式收集相关信息。  结果  调查县无害化卫生厕所普及率为53.34 %,东、中、西部的差异有统计学意义(P < 0.05),无害化卫生厕所普及率与区域的人均年纯收入呈正相关(r = 0.997,P < 0.05)。500个村粗死亡率为563/10万,心脏病、恶性肿瘤、脑血管病是死亡的主要原因。垃圾、污水处理厂人口覆盖率平均为58.50 %和40.80 %,东、中、西部差异有统计学意义(P < 0.05)。农村土壤中蛔虫卵检出率为17.20 %,东、中、西部差异无统计学意义(P = 0.31),活蛔虫卵检出率为5.20 %,东、中、西部差异有统计学意义(P < 0.05);东、中、西部的蛔虫卵检出率与人均年纯收入呈显著负相关(r = – 0.998,P = 0.04)。土壤重金属合格率为87.40 %,东、中、西部差异有统计学意义(P < 0.05),土壤中镉合格率为89.00 %,东、中、西部差异有统计学意义(P < 0.05)。  结论  山东省不同地域的农村环境因素和疾病间明显相关,西部地区土壤中活蛔虫卵检出率偏高;东部地区土壤污染的主要因素是镉;应针对不同地域特点采取相应的干预和控制措施。  相似文献   
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