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991.
秦皮水煎剂的遗传毒性研究 总被引:1,自引:0,他引:1
目的:研究秦皮水煎剂的遗传毒性.方法:采用小鼠淋巴瘤细胞试验(MLA)和小鼠骨髓微核试验(MNT).MLA试验中,秦皮水煎剂(含生药)1.71,3.42,6.83,13.65 g·L~(-1) 4个质量浓度组,超纯水阴性对照组及甲基甲烷磺酸酯、环磷酰胺阳性对照组,分别在非代谢活化(-S9)和代谢活化(+S9)条件下与L5178Y细胞作用3 h,表达2 d,制备基因突变频率平板并培养12~13 d,计数含大、小突变细胞集落的孔数,计算每组总突变率和小集落突变百分率;MNT试验中,3个剂量组(含生药)7.14,14.28,28.55 g·kg~(-1),氯化钠注射液阴性对照组和环磷酰胺阳性对照组,每组10只ICR小鼠,雌雄各半,间隔24 h实施2次灌胃给药,制作骨髓涂片,镜检每只小鼠2 000个嗜多染红细胞中含微核的嗜多染红细胞数,计算每组动物嗜多染红细胞微核率.结果:MLA试验,-S9条件下各浓度组诱发的总突变率呈现浓度依赖性增加,13.65,6.83 g·L~(-1)组与阴性对照组比较有统计学意义(P<0.01),小集落突变百分率随浓度增加而升高,+S9条件下的各浓度组总突变率和小集落突变百分率均与阴性对照组相近;MNT试验,各剂量组无明显骨髓抑制作用,诱发的小鼠骨髓嗜多染红细胞微核率与阴性对照组比较末见明显增加.结论:秦皮水煎剂在体外非代谢活化条件下可诱发L5178Y细胞tk~(+/-)位点突变并导致染色体损伤,提示其可能存在直接诱变物;秦皮水煎剂对小鼠骨髓细胞染色体无明显损伤作用,经体内、外代谢活化后均未显示遗传毒作用. 相似文献
992.
1,2-二氯乙烷致小鼠血淋巴细胞遗传毒性研究 总被引:1,自引:0,他引:1
目的研究1,2-二氯乙烷(1,2-DCE)对小鼠血淋巴细胞DNA和骨髓细胞染色体的损伤作用,探讨1,2-二氯乙烷的遗传毒性。方法采用单细胞凝胶电泳和微核试验方法,分别检测1,2-DCE不同染毒剂量(50,100,200,400 mg/kg)小鼠外周血淋巴细胞DNA和骨髓细胞染色体损伤情况。结果除50 mg/kg剂量组外,小鼠血淋巴细胞的彗星细胞率及尾长、骨髓细胞微核率随1,2-DCE染毒剂量的增加而增加(P<0.01)。其中,400 mg/kg剂量组彗星细胞率、平均尾长、微核率分别为45.5%,(37.24±3.17)μm,12.0‰,显著高于阴性对照组和50 mg/kg剂量组(P<0.01)。染毒剂量与彗星细胞率、平均尾长、微核率之间存在着剂量-反应关系(R彗星率=0.980 2,R彗尾长=0.976 6,R微核率=0.975 1,P<0.01)。结论1,2-DCE可导致小鼠血淋巴细胞DNA损伤和骨髓细胞染色体异常。表明1,2-DCE具有细胞遗传毒性。 相似文献
993.
994.
阿特拉津对小鼠微核及精子畸形率的影响 总被引:6,自引:0,他引:6
目的 探讨阿特拉津对小鼠的致突变性。方法 应用小鼠骨髓细胞微核试验和精子畸形试验。结果 骨髓微核实验结果为阴性(P〉0.05);高剂量组(438mg/kg)精子畸形率显升高(P〈0.05),但无剂量反应关系,亦不能定为阳性结果。结论 在本实验条件下阿特拉津无致突变作用。 相似文献
995.
采取因职业而接触乙烯类或苯类诱变剂的孕妇静脉血和其新生儿脐带血进行SCE和MN测定,发现接触两类诱变剂的母血SCE分别为8.55±0.84和9.44±1.12,均高于对照组母血SCE(7.68±1.40);而微核率分别为0.833‰和0.75‰也高于对照组母血微核率(0.267‰);接触两类诱变剂的脐血SCE分别为8.44±1.43和8.75±0.88,均高于对照组脐血SCE(6.71±1.27);而微核率分别为0.727‰和0.818‰,也分别高于对照组脐血微核率。结果还表明母亲被动吸烟增强了化学诱变剂对新生儿的遗传毒性作用。本研究首次发现乙烯类诱变剂对新生儿具有遗传危害。 相似文献
996.
维生素C拮抗HgCl_2的致微核作用 总被引:2,自引:0,他引:2
研究表明,给小鼠腹腔注射HgCl_20.5和1.0mg/kg后,其诱发的微核率显著地高于蒸馏水对照组。而给小鼠腹腔注射VC50mg/kg以上,可降低HgCl_2的致微核作用,注射剂量达100和200mg/kg时,其作用更明显(P<0.001)。另外,不论是在HgCl_2染毒前4h或染毒后2h内给子VC,均可明显地降低HgCl_2的致微核作用,尤其是在HgCl_2染毒前30~60min内和染毒后30min时给VC、则其抗致微核作用愈益明显。如给小鼠饮用含VC2.5g/L的水一个月后,也可显著地降低HgCl_2的致微核作用。 相似文献
997.
998.
Gaofeng Chen Hairuo Wen Zhihui Mao Jie Song Hua Jiang Weifan Wang Ying Yang Yufa Miao Chao Wang Zhiying Huang Xue Wang 《Environmental and molecular mutagenesis》2019,60(1):56-71
The utility and sensitivity of the newly developed flow cytometric Pig-a gene mutation assay have become a great concern recently. In this study, we have examined the feasibility of integrating the Pig-a assay as well as micronucleus and Comet endpoints into acute and subchronic general toxicology studies. Male Sprague–Dawley rats were treated for 3 or 28 consecutive days by oral gavage with procarbazine hydrochloride (PCZ) or ethyl carbamate (EC) up to the maximum tolerated dose. The induction of CD59-negative reticulocytes and erythrocytes, micronucleated reticulocytes in peripheral blood, micronucleated polychromatic erythrocytes in bone marrow, and Comet responses in peripheral blood, liver, kidney, and lung were evaluated at one, two, or more timepoints. Both PCZ and EC produced positive responses at most analyzed timepoints in all tissue types, both with the 3-day and 28-day treatment regimens. Furthermore, comparison of the magnitude of the genotoxicity responses indicated that the micronucleus and Comet endpoints generally produced greater responses with the higher dose, short-term treatments in the 3-day study, while the Pig-a assay responded better to the cumulative effects of the lower dose, but repeated subchronic dosing in the 28-day study. Collectively, these results indicate that integration of several in vivo genotoxicity endpoints into a single routine toxicology study is feasible and that the Pig-a assay may be particularly suitable for integration into subchronic dose studies based on its ability to accumulate the mutations that result from repeated treatments. This characteristic may be especially important for assaying lower doses of relatively weak genotoxicants. Environ. Mol. Mutagen. 60:56–71, 2019. © 2018 Wiley Periodicals, Inc. 相似文献
999.
Ruixue Chen Changhui Zhou Yiyi Cao Jing Xi Toko Ohira Liang He Pengcheng Huang Xinyue You Weiying Liu Xinyu Zhang Shuangcheng Ma Tianpei Xie Yan Chang Yang Luan 《Environmental and molecular mutagenesis》2020,61(2):266-275
A newly developed in vivo Pig-a gene mutation assay displays great potential for integration into genotoxicity tests. To obtain more evidence for application of the Pig-a assay, we integrated this assay, micronucleus test in peripheral blood (MN-pb test) and bone marrow (MN-bm test), as well as a Comet assay into a transgenic RasH2 mice carcinogenicity study. Fourteen male RasH2 mice and five wild-type (WT) mice were treated with a strong mutagen aristolochic acid I at a dose of 5 mg/kg/day for 4 consecutive weeks. Mice recovered in 5 weeks. Peripheral bloods were collected for Pig-a assay, MN-pb test, and Comet assay at several time points, while bone marrow and target organs were harvested for the MN-bm test and pathological diagnosis after mice were euthanized. Finally, 13 of the 14 RasH2 mice developed squamous cell carcinomas in the forestomach, while there were no carcinomas in the WT mice. Pig-a mutant frequencies (MFs) consecutively increased throughout the study to a maximum value of approximately 63-fold more than background. These frequencies were relative to the incidence, size, and malignant degree of tumors. Micronucleated reticulocytes increased from Day 1 to Day 49, before returning to background levels. No positive responses were observed in either the MN-bm test or the Comet assay. Results suggested that, when compared with the other two tests, the Pig-a assay persistently contributed to sustaining MFs, enhanced detection sensitivity due to the accumulation of Pig-a mutations, and demonstrated better predictability for tumorigenicity. Environ. Mol. Mutagen. 61:266–275, 2020. © 2019 Wiley Periodicals, Inc. 相似文献
1000.