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Genotoxicity and physicochemical characteristics of traffic-related ambient particulate matter 总被引:1,自引:0,他引:1
de Kok TM Hogervorst JG Briedé JJ van Herwijnen MH Maas LM Moonen EJ Driece HA Kleinjans JC 《Environmental and molecular mutagenesis》2005,46(2):71-80
Exposure to ambient particulate matter (PM) has been linked to several adverse health effects. Since vehicular traffic is a PM source of growing importance, we sampled total suspended particulate (TSP), PM(10), and PM(2.5) at six urban locations with pronounced differences in traffic intensity. The mutagenicity, DNA-adduct formation, and induction of oxidative DNA damage by the samples were studied as genotoxicological parameters, in relation to polycyclic aromatic hydrocarbon (PAH) levels, elemental composition, and radical-generating capacity (RGC) as chemical characteristics. We found pronounced differences in the genotoxicity and chemical characteristics of PM from the various locations, although we could not establish a correlation between traffic intensity and any of these characteristics for any of the PM size fractions. Therefore, the differences between locations may be due to local sources of PM, other than traffic. The concentration of total (carcinogenic) PAHs correlated positively with RGC, direct and S9-mediated mutagenicity, as well as the induction of DNA adducts and oxidative DNA damage. The interaction between total PAHs and transition metals correlated positively with DNA-adduct formation, particularly from the PM(2.5) fraction. RGC was not associated with one specific PM size fraction, but mutagenicity and DNA reactivity after metabolic activation were relatively high in PM(10) and PM(2.5), when compared with TSP. We conclude that the toxicological characteristics of urban PM samples show pronounced differences, even when PM concentrations at the sample sites are comparable. This implies that emission reduction strategies that take chemical and toxicological characteristics of PM into account may be useful for reducing the health risks associated with PM exposure. 相似文献
13.
我国正常生育力男子精浆的微量元素研究 总被引:12,自引:5,他引:7
本文报告测试了68例正常生育力成年男子精浆中的锌、铜,铁等微量元素和镁,测试结果如下:锌130±5.64μg/ml,铜1.84±0.158μg/ml,铁0.801±0.104μg/ml,镁103.86±10.01μg/ml。所测得的数值均在正常范围内。在正常范围内的精液,精浆中的锌、镁含量与精液质量(精子密度和活动力)之间无显著差异。但铜的含量与精子活动度关系密切,含量高则活动度差,反之则活动度好。铁的含量与精子密度关系也十分密切,含量高时精子密度也高。 相似文献
14.
目的 了解酒泉市戈壁设施种植的番茄、葫芦、黄瓜、辣椒、豆角中铅、砷、汞、镉的污染状况,评估人体摄入后的健康风险。方法 利用国家标准检验方法,在酒泉市总寨和东洞戈壁农业产业园区采集检测274份主栽蔬菜中铅、砷、汞、镉含量,结合单因子污染指数和内梅罗污染指数法对蔬菜受重金属污染的程度进行评价,利用靶标污染系数法对蔬菜中重金属对人体的健康风险进行评估。结果 274份蔬菜中铅、砷、汞和镉的含量范围分别为0~0.050 1 mg/kg、0~0.053 8 mg/kg、0~0.001 0 mg/kg和0~0.048 8 mg/kg,平均含量分别为0.010 3、0.010 3、0.000 2和0.008 7 mg/kg,均未超出国家标准规定的食品中污染物限量。5种蔬菜中4种重金属的污染指数均低于0.7,靶标危害系数均小于1。结论 酒泉市总寨和东洞戈壁农业产业园区主栽的5种蔬菜受铅、砷、汞、镉污染程度较轻,属于清洁水平,处于安全级别,膳食摄入风险较低。对比其它地区蔬菜,酒泉戈壁设施蔬菜中重金属含量总体不高,与有机设施蔬菜基地结果接近。 相似文献
15.
覆膜自膨式金属支架治疗恶性食管气管瘘 总被引:2,自引:1,他引:1
目的 探讨覆膜金属支架治疗恶性食管气管瘘的效果及并发症。方法 在X线引导下14例食管气管瘘用国产覆膜支架治疗,门诊行食管造影或电话随访。结果 除1例瘘口封堵不全外,其余13例瘘口完全封堵,未发生因操作引起的并发症。8例进普食,6例进半流食,12例肺部感染得到控制。并发症:严重胸痛3例,支架移位致瘘再开放1例,颈动脉及左侧喉返神经受压致头晕及咽麻痹各1例。8例病人死亡,术后生存时间1.4~12个月, 相似文献
16.
Use of crayfish in biomonitoring studies of environmental pollution of the river Meuse 总被引:1,自引:0,他引:1
Schilderman PA Moonen EJ Maas LM Welle I Kleinjans JC 《Ecotoxicology and environmental safety》1999,44(3):241-252
The river Meuse, located in western Europe, is contaminated by different pollutants, of both organic and inorganic nature. The predominant sources of Meuse contamination in The Netherlands are agricultural activities and pollution derived from urban areas. Crayfish, water, and sediment samples were collected at four different locations of the river Meuse, in order to cover a large part of the catchment area of this river in The Netherlands. Crayfish may be very useful in biomonitoring studies, since they can integrate body load by pollutants over time in an area-bound manner. In these crayfish, levels of aromatic DNA adducts, heavy metal residues, polychlorinated biphenyls (PCBs), and organochlorine pesticides were determined in hepatopancreatic tissue. Also analyzed were water and sediment samples derived from the same locations, for polycyclic aromatic hydrocarbons (PAHs), heavy metals, and organochlorine compounds. In sediments from the four different sampling sites, no clear differences were observed in PCB levels. Organochlorine pesticide concentrations were highest at location A, the most upstream sampling site, whereas a general decrease was observed following the river Meuse downstream. A similar pattern was observed for the metal compounds. For PAH sediment levels no consistent tendency could be observed. Highest values were detected at site B, followed by, respectively, locations A, D, and C. In water samples, a different pattern was observed. The highest metal concentration was observed at location D, whereas the total organochlorine level was higher at sites B and D, compared to the two other sampling sites. Differences in pollution levels in crayfish between sampling sites were evident. Site D, the most downstream-situated site examined, appeared to be the most polluted site with respect to PCBs, DDT, DDE, and Cu in crayfish. Moreover, DNA adduct levels, which may serve as a dosimeter for the internal dose of aromatic compounds such as PAHs and PCBs, were also significantly higher in hepatopancreatic tissue of crayfish captured at site D, compared to the three other sampling sites. Moreover, significant correlations were observed between DNA adduct levels and the lower chlorinated PCB congeners (PCB 28-PCB 101). By correlating the different pollutants in water and/or sediment with xenobiotic levels in crayfish, no consistency could be observed, indicating that monitoring aquatic species may provide specific information on the presence of surface water pollutants. These results indicate that crayfish can be used as biological indicators of exposure to both organic and inorganic pollution in aquatic systems. 相似文献
17.
18.
黄芪中重金属超临界CO_2净化技术研究 总被引:15,自引:0,他引:15
目的利用超临界CO2 萃取技术净化黄芪中重金属。方法a 以二乙基二硫代氨基甲酸钠(DDTC)为金属络合剂 ,用超临界流体萃取技术净化药材中的重金属 ,并对萃取方案进行最优化。b 选择不同的混酸消化液完全消解药材后 ,以空气 乙炔火焰AAS法和氢化物发生AAS法分别测定其中的铅 (Pb)、镉 (Cd) ,以及砷 (As)、汞 (Hg)。c 采用UCTRONVX -ODS(2 5 0mm×4 6mm ,5 μm)色谱柱 ,以乙腈 水 (V∶V =30∶70 )为流动相 ,检测波长为 2 0 3nm ,卡马西平为内标 ,测定黄芪中黄芪甲苷的含量。结果与结论a 确定了药材中重金属的最佳萃取条件。在最佳萃取条件下 ,重金属净化率达到 85 %以上 ;同时 ,中药材中的有效成分损失低于 5 %。b 建立了药材中金属元素和有效成分的含量测定方法 ,为正确评价中药材的质量奠定了基础 ,可用于正确评价净化前后药材的质量变化 相似文献
19.
淫羊藿中重金属超临界CO2流体净化技术研究 总被引:8,自引:0,他引:8
目的利用超临界CO2萃取技术(SFE)净化淫羊藿中重金属.方法①以二乙基二硫代氨基甲酸钠(DDC-Na)为金属络合剂,用超临界流体萃取技术净化药材中的重金属,并对萃取方案进行最优化.②选择不同的混合酸消化液完全消解药材后,以空气-乙炔火焰原子吸收法(AAS)和氢化物发生AAS法分别测定其中的铅(Pb)、镉(Cd)以及砷(As)、汞(Hg).③采用Kromasil C18(250 mm×4.6 mm,5 μm )色谱柱,以甲醇-水(60∶40)为流动相,检测波长为270 nm,测定淫羊藿中淫羊藿苷的含量.结果在最佳萃取条件下,重金属净化率达到90%以上,中药材有效成分的损失<5%.结论确定了药材中重金属的最佳萃取条件. 相似文献
20.
目的:科学地控制纯化水中重金属的限度。方法:采用精制处理后的检查专用试验水,按《中国药典》方法检查纯化水中的 重金属。结果:精制处理后的检查专用试验水用于检查纯化水中的重金属可排除干扰。结论:精制处理后的检查专用试验水中的重 金属含量限定在极微量范围内,可极大地减少干扰,使检查结果更加准确。 相似文献