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11.
本文报道2例肠梗阻和1例有机磷农药中毒患者出现暂时性高血糖症。该3例患者均无糖尿病史,因有重度失水,经大量补液纠正失水后血糖迅速恢复正常。口服葡萄糖耐量试验正常。作者认为非糖尿病患者可因重度失水而致应激性高血糖症。 相似文献
12.
目的探讨晚期氧化蛋白(AOPP)在急性有机磷农药中毒(AOPP)患者中的临床意义。方法采用酶联免疫分析法(ELISA)动态检测90例有机磷农药中毒患者和30例健康对照者血清晚期氧化蛋白的含量,并探讨其与病情的相关性。结果AOPP患者血浆中晚期氧化蛋白含量发病后的第1天〉第3天〉第7天与健康对照组比较,P均〈0.01。血清CRP的含量在患者中毒后的第1天〉第3天〉第7天与健康对照组比较,P均〈0.01。在发病的第1天,AOPP患者血清晚期氧化蛋白和CRP的含量重度中毒组〉中度中毒组〉轻度中毒组与健康对照组比较,P均〈0.01。在第1天,AOPP患者的病情程度即MODS的评分值与血清晚期氧化蛋白和CRP的含量均呈明显的正相关性(r1=0.590和r2=0.627,P均〈O.01),而血清晚期氧化蛋白和CRP的含量之间也呈明显的正相关性(r3=0.792,P〈0.01)。结论晚期氧化蛋白的含量随急性有机磷农药中毒患者的病情和炎症反应加重而升高。晚期氧化蛋白可能参与了有机磷农药中毒患者发生多脏器功能障碍的病理生理过程。 相似文献
13.
Characterization of a 105-kDa plasma membrane associated glycoprotein that is involved in West Nile virus binding and infection 总被引:3,自引:0,他引:3
This study attempts to isolate and characterize West Nile virus-binding molecules on the plasma membrane of Vero and murine neuroblastoma cells that is responsible for virus entry. Pretreatment of Vero cells with proteases, glycosidases (endoglycosidase H, alpha-mannosidase), and sodium periodate strongly inhibited West Nile virus infection, whereas treatments with phospholipases and heparinases had no effect. The virus overlay protein blot detected a 105-kDa molecule on the plasma membrane extract of Vero and murine neuroblastoma cells that bind to WN virus. Treatment of the 105-kDa molecules with beta-mercaptoethanol resulted in the virus binding to a series of lower molecular weight bands ranging from 30 to 40 kDa. The disruption of disulfide-linked subunits did not affect virus binding. N-linked sugars with mannose residues on the 105-kDa membrane proteins were found to be important in virus binding. Specific antibodies against the 105-kDa glycoprotein were highly effective in blocking virus entry. These results strongly supported the possibility that the 105-kDa protease-sensitive glycoprotein with complex N-linked sugars could be the putative receptor for WN virus. 相似文献
14.
目的 建立运用气相色谱-串联质谱(GC-MS/MS)法快速筛查460份中药材及其中药饮片(43份)中常用的50种农药残留。方法 通过对比《中国药典》2020版中药中农药残留的前处理方法,优选中药中50种农药残留的适配性前处理方法。中药样品经乙腈溶剂提取,以Qu ECh ERS法处理,采用GC-MS/MS测定,内标法定量。结果 在460份检测样品中共检出农药残留66份,总检出率为14.3%,检出禁用农药6份,检出率为1.3%,43份中药饮片中农药残留检出率为11.6%,未检出禁用农药。农残的检出是季节性分布集中出现在第3、4季度,农贸市场和种植地的农残检出率明显高于医院和药店,并且存在农残超标情况。中药中根类和叶类受污染最重,中药材全草类中农药残留最多,检出率为20.4%,其次为叶类18.3%和根茎类16.3%,中药饮片中农残最高为叶类,检出率为15.4%,全草类检出率为11.1%、根茎类检出率为6.2%,全草类、根茎类和叶类存在样品中检出多种农药残留的现象。结论 该方法简单快速、灵敏度高、重现性好、准确度高,可快速筛查中药中农药残留,为保障中药质量提供参考。 相似文献
15.
目的 建立菊花茶中56种农药残留的分散固相萃取(QuEChERS) - 气相色谱串联三重四级杆质谱(GC - MS/MS)测定方法。方法 样品用乙腈提取,PSA+C18+GCB混合型分散固相萃取剂净化,DB - 5MS色谱柱分离,多反应监测模式(MRM)检测,外标法定量。结果 在0.005~500 mg/L范围内,56种农药的线性相关系数均≥0.995,方法定量限为0.002~0.057 mg/kg,平均回收率为60.0%~118.0%,相对标准偏差(RSD)为0.53%~20.09%。结论 该方法简单快速灵敏,可以实现菊花茶中农药残留的快速高通量检测。 相似文献
16.
UV filters with antagonistic action at androgen receptors in the MDA-kb2 cell transcriptional-activation assay. 总被引:4,自引:0,他引:4
Risheng Ma Bea Cotton Walter Lichtensteiger Margret Schlumpf 《Toxicological sciences》2003,74(1):43-50
The fact that certain ultraviolet (UV) filters used in cosmetics display estrogenic activity prompted us to study potential actions on androgen receptors (AR) in the human breast carcinoma cell line MDA-kb2, which expresses functional endogenous AR and glucocorticoid receptors (GR) and is stably transfected with a luciferase reporter plasmid. Dihydrotestosterone (DHT), methyltrienolone (R1881), methyltestosterone, danazol, and androstenedione increased luciferase activity, with EC50 values between 0.11 nM (R1881), 0.14 nM (DHT), and 73.5 nM (androstenedione). DHT-induced luciferase gene expression was inhibited by nonsteroidal antiandrogens, hydroxyflutamide, flutamide, bicalutamide, and vinclozolin. In contrast, the steroidal AR agonist/antagonist cyproterone actetate showed agonistic activity in the absence and presence of DHT, which was not blocked by hydroxyflutamide and thus seems not to be mediated by AR. GR-mediated activation of luciferase by dexamethasone was 100 times less potent than DHT and was not antagonized by hydroxyflutamide. The cell line was used for screening of UV filters, benzophenone-3 (Bp-3), benzophenone-4, 3-benzylidene camphor, 4-methylbenzylidene camphor, butyl-methoxy-dibenzoylmethane, homosalate (HMS), octyl-dimethyl-PABA, and octyl-methoxycinnamate. Two of these, Bp-3 and HMS, antagonized DHT-induced AR activation below cytotoxic concentrations, with IC50 of 5.57 10-6 M (HMS) and 4.98 10-6 M (Bp-3). None of the eight UV filters displayed agonistic activity when tested alone, but high concentrations of Bp-3 induced an increase of luciferase activity in the presence of dexamethasone, which was not blocked by hydroxyflutamide or the estrogen antagonist, ICI 182,780. These data indicate that the UV filters Bp-3 and HMS possess antiandrogenic activity in vitro in addition to estrogenic activity. 相似文献
17.
目的 对中药瓜蒌进行有机氯农药的残留量测定,开展瓜蒌质量标准的规范化研究。方法 采用气相色谱法对六六六(BHC)4种异构体、滴滴涕(DDT)4种异构体和五氯硝基苯(PCNB)进行测定。结果 11个瓜蒌样品中六六六的总含量位于2.86~21.85 μg·kg-1的范围,滴滴涕的总含量位于2.86~50.04 μg·kg-1的范围,五氯硝基苯的含量低于4.94 μg·kg-1。结论 所测瓜蒌中农药残留量低于我国国家相关的规定限量;样品中商品瓜蒌的农药残留量高于非商品瓜蒌的残留量,提示我们在瓜蒌的贮存、运输等过程中应该限制农药的污染。 相似文献
18.
19.
Anne Marie Vinggaard Sofie Christiansen Peter Laier Mette Erecius Poulsen Vibeke Breinholt Kirsten Jarfelt Helene Jacobsen Majken Dalgaard Christine Nellemann Ulla Hass 《Toxicological sciences》2005,85(2):886-897
Prochloraz is a commonly used fungicide that has shown multiple mechanisms of action in vitro. It antagonizes the androgen and the estrogen receptors, agonizes the Ah receptor, and inhibits aromatase activity. In vivo prochloraz acts antiandrogenically in the Hershberger assay by reducing weights of reproductive organs, affecting androgen-regulated gene expressions, and increasing luteinizing hormone (LH) levels. The purpose of this study was to investigate reproductive toxic effects after exposure during gestation and lactation to prochloraz alone and a mixture of five pesticides (deltamethrin, methiocarb, prochloraz, simazine, and tribenuron-methyl). Prochloraz (30 mg/kg/day) or the mixture (20 mg/kg/day) was dosed to pregnant Wistar dams from gestational day (GD) 7 until postnatal day (PND) 16. Some dams were taken for cesarean section at GD 21, and others were allowed to give birth. Results showed that prochloraz and the mixture significantly reduced plasma and testicular testosterone levels in GD 21 male fetuses, whereas testicular progesterone was increased. Gestational length was increased by prochloraz. Chemical analysis of the rat breast milk showed that prochloraz was transferred to the milk. In males a significant increase of nipple retention was found, and the bulbourethral gland weight was decreased, whereas other reproductive organs were unaffected. In addition cytochrome P450 (CYP)1A activities in livers were induced by prochloraz, possibly as a result of Ah receptor activation. Behavioral studies showed that the activity level and sweet preference of adult males were significantly increased. Overall these results strongly indicate that prochloraz feminizes the male offspring after perinatal exposure, and that these effects are due, at least in part, to diminished fetal steroidogenesis. 相似文献
20.
目的探讨口服有机磷中毒患者心跳骤停时应用食道心脏调搏进行救治的疗效。方法15例心脏骤停患者,在常规治疗基础上应用食道心脏调搏方法抢救。结果15例中救治成功13例。结论经食道心脏起搏方法简便、操作速度快、无创、无需消毒、效果良好,适用于临床紧急起搏,尤其适用于基层医院。 相似文献