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1.
We hypothesized that increased ambient concentrations of metals, as a consequence of escalating urbanization and industrialization of the Gulf region will respond in increased contamination of edible fish species. In this study, we report concentrations of chromium, manganese, cobalt, copper, zinc, arsenic, cadmium, mercury and lead in meat and liver of wild Red-spot emperor (Lethrinus lentjan) from three sampling points at the UAE coast. Analysis was performed by the ICP-MS/microwave digestion. Our study has shown that meat and liver metal content was significantly higher in areas with higher industrial activity, although metal values did not exceed permitted levels of fish for human consumption.  相似文献   
2.
ICP-MS法同时测定食品中8种微量有害元素的方法研究   总被引:8,自引:1,他引:8  
〔目的〕建立一种快速消解并同时测定食品中微量有害元素的方法。〔方法〕采用微波消解样品。选择Rh和Re作内标的外部校准形式 ,应用ICP -MS法同时测定食品中As、Se、Pd、Cd、Sn、Hg、Tl和Pb等 8种有害元素的测定方法。对照分析了参考标准物质。〔结果〕方法简便、快速、准确 ,灵敏度高。对于所测元素 ,校准曲线的相关系数 >0 .9990 ,回收率范围为 86% -10 4% ,相对标准偏差 0 .7% -6.8%。〔结论〕食品中As、Se、Pd、Cd、Sn、Hg、Tl和Pb等 8种有害元素可用ICP -MS法同时测定。  相似文献   
3.
目的:研究电感耦合等离子体质谱(ICP-MS)测定烹调用铝箔中铅、砷、镉、汞、铝、硒、锰、铁、铜、锌、铬、镍、锡13种元素的方法。方法:样品经浸泡处理后,以Rh作为内标物质,可有效地校正了基体干扰,直接用ICP-MS同时测定上述13种元素。结果:13种元素的检出限分别在(10~100)mg/L之间,对标准物质GBW08608-4021测定结果满意。结论:ICP-MS法分析铝箔中的多种元素分析速度快,线性范围宽,精密度、准确度高。  相似文献   
4.
目的:建立电感耦合等离子体质谱(简称ICP-MS)法测定乐力中硼、镁、硅、磷、钙、锰、铜和锌等8种元素含量。方法:供试品消化处理后,使用电感耦合等离子体质谱仪同时测定8种元素,并通过标准曲线计算含量。结果:8种元素的标准曲线线性良好,方法的加样回收率为93.1%-100.6%,RSD为2.9%-7.8%。结论:本法专属性好,灵敏度高,准确快捷,可用于分析营养类制剂中的多种元素。  相似文献   
5.
Cobalt is a substance that has been abused for athletic performance enhancement and has thus been prohibited by human and animal sports doping control authorities. However, because cobalt is present in humans and animals as a trace element, a certain level of cobalt is naturally present in their excretions. In the racing industry, cobalt is a controlled substance with a threshold concentration specified by the International Agreement on Breeding, Racing and Wagering (IABRW) for international harmonization. Due to environmental and feed consumption differences among countries, regional cobalt concentration trends should be evaluated before cobalt testing is introduced. In this study, we conducted a preliminary evaluation of the urinary concentration of cobalt among a population of racehorses in Korea using inductively coupled plasma mass spectrometry (ICP-MS) analysis, followed by analysis of the urinary release of cobalt after the administration of cobalt chloride in various situations. The normal distribution for the Korea-based racehorses was used to determine a urine concentration limit (96.5 ng/ml, risk factor of 1 in 10,000). After the intravenous (IV) administration of CoCl2, the initial elimination of cobalt was rapid. A high concentration (over 2,000 ng/ml) and a slow excretion pattern were observed during the final 2 weeks of the 3-week observation period. When CoCl2 was administered orally, maximum concentration (Cmax, 92–992 ng/ml) was observed at 6–8 h.  相似文献   
6.
Large efforts are invested on the development of in vitro tests to evaluate nanomaterial (NM) toxicity. In order to assess the relevance of the adverse effects identified in in vitro toxicity tests a thorough understanding of the biokinetics of NMs is critical. We used different in vitro and in vivo test methods to evaluate cell uptake and oral absorption of titanium dioxide nanoparticles (TiO2 NPs). These NPs were readily uptaken by A549 cells (carcinomic human alveolar basal epithelial cells) in vitro. Such rapid uptake contrasted with a very low oral absorption in a differentiated Caco-2 monolayer system (human epithelial colorectal adenocarcinoma cells) and after oral gavage administration to rats. In this oral study, no significant increase in the levels of titanium was recorded by ICP-MS in any of the tissues evaluated (including among other: small intestine, Peyer's patches, mesenteric lymph nodes, liver, and spleen). No NPs were observed by TEM in sections of the small intestine, except for several particles in the cytoplasm of a cell from a Peyer's Patch area. The observation of NPs in Peyer's Patch suggests that the Caco-2 monolayer system is likely to underestimate the potential for oral absorption of NPs and that the model could be improved by including M-cells in co-culture.  相似文献   
7.
目的 给予家兔阴道内纳米银凝胶后,研究银在家兔体内的分布情况.方法 单剂量和多剂量经♀家兔阴道给予纳米银凝胶200 mg∶ kg-1后,于不同时间点处死家兔并剖取主要组织器官,用ICP-MS法测定给药前、后家兔各器官中银的含量.结果 与0h组比较,单剂量给药后,阴道、子宫和肝脏中银的含量明显增加,其余组织中未见明显分布,给药72 h后各组织中银的含量均恢复至本底水平;多剂量给药后,末次给药2 ~24 h内阴道、子宫、肝脏、脾、肾、大肠和小肠中有银的分布,心、脑、肺和胃未见明显分布,末次给药72 h后各组织中银的含量均恢复至本底水平.结论 单剂量和多剂量经家兔阴道给予纳米银凝胶后,给药2 ~24 h内银在组织中有分布,给药72 h后各组织中均未见明显银蓄积.  相似文献   
8.
目的:建立电感耦合等离子体质谱法测定酒石酸长春瑞滨中有害元素及催化剂银残留的方法。方法:用微波消解处理样品,电感耦合等离子体质谱内标法测定银、钒、铬、钴、镍、铜、砷、钼、镉、锡、锑、钡、铅、汞的含量。结果:上述14种元素的方法检出限分别为0.003、0.020、0.141、0.069、0.077、0.362、0.031、0.057、0.022、0.078、0.017、0.724、0.095、0.005 ng·mL-1,线性关系良好(r≥0.9988),回收率为86%~110%,RSD小于15%;同时,给出了此方法各元素的不确定度评定程序。结论:本方法采用在线加内标,可有效校正仪器漂移,抑制基体干扰,提高准确率,多元素测定便捷、准确、灵敏、可靠,可用于酒石酸长春瑞滨中有害元素及催化剂银残留的测定。  相似文献   
9.
Health impacts of inhalation exposure to engineered nanomaterials have attracted increasing attention. In this paper, integrated analytical techniques with high sensitivity were used to study the brain translocation and potential impairment induced by intranasally instilled copper nanoparticles (CuNPs). Mice were exposed to CuNPs in three doses (1, 10, 40 mg/kg bw). The body weight of mice decreased significantly in the 10 and 40 mg/kg group (p < 0.05) but recovered slightly within exposure duration. Inductively coupled plasma mass spectrometry (ICP-MS) analysis showed that CuNPs could enter the brain. Altered distribution of some important metal elements was observed by synchrotron radiation X-ray fluorescence (SRXRF). H&E staining and immunohistochemical analysis showed that CuNPs produced damages to nerve cells and astrocyte might be the one of the potential targets of CuNPs. The changes of neurotransmitter levels in different brain regions demonstrate that the dysfunction occurred in exposed groups. These data indicated that CuNPs could enter the brain after nasal inhalation and induced damages to the central nervous system (CNS). Integration of effective analytical techniques for systematic investigations is a promising direction to better understand the biological activities of nanomaterials.  相似文献   
10.
目的比较电感耦合等离子体质谱法与国标法的水碘检测结果。方法从方法的灵敏度,精密度和准确度等指标进行比较。结果电感耦合等离子体质谱法测定水碘检出限0.2μg/L,加标回收率95.0%~102.0%,相对标准偏差2.0%,两种方法对实际样品的分析结果没有显著统计学意义。结论电感耦合等离子体质谱法操作简单、快速、准确,是一种检测水碘的较好方法。  相似文献   
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