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991.
The role of sex hormone-binding globulin and androgen receptor gene variants in the development of polycystic ovary syndrome 总被引:1,自引:0,他引:1
Xita N Georgiou I Lazaros L Psofaki V Kolios G Tsatsoulis A 《Human reproduction (Oxford, England)》2008,23(3):693-698
BACKGROUND: Polycystic ovary syndrome (PCOS) may be programmed in utero by androgen excess. Our aim was to examine the role of the sex hormone-binding globulin (SHBG) and androgen receptor (AR) gene polymorphisms, in the phenotypic expression of PCOS. METHODS: A cohort of 180 women with PCOS and 168 healthy women of reproductive age were investigated. BMI was recorded and the hormonal profile was determined on Day 3-5 of menstrual cycle. DNA was extracted from peripheral blood leucocytes and the SHBG(TAAAA)n and AR(CAG)n polymorphisms were genotyped by PCR. RESULTS: Genotype analysis revealed six SHBG(TAAAA)n alleles with 6-11 repeats and 19 AR(CAG)n alleles with 6-32 repeats, present in both PCOS and control women. Long SHBG(TAAAA)n alleles (>8 repeats) were at greater frequency in PCOS than normal women (P = 0.001), whereas short AR(CAG)n alleles (相似文献
992.
Lee KS Han TH Jo JY Kang G Lee SY Ryu PD Im JH Jeon BH Park JB 《Neuroscience letters》2008,439(2):138-142
Activation of serotonin (5-hydroxytryptamine, 5-HT) receptors produces various autonomic and neuroendocrine responses in the hypothalamic paraventricular nucleus (PVN), including increased blood pressure and heart rate. However, the role(s) of 5-HT on the local GABA synaptic circuit have not been well understood in the PVN, where the inhibitory neurotransmitter GABA plays a key role in the modulation of sympathoexcitatory outflow. In the present study, we examined the effects of 5-HT on GABA synaptic transmission in presympathetic PVN neurons projecting to spinal cord using patch-clamp electrophysiology combined with tract-tracing techniques. Bath application of 5-HT (0.01-100 microM) reversibly decreased the frequency of spontaneous GABAergic inhibitory postsynaptic currents (sIPSC) in a concentration dependent manner (IC50, 0.07 microM), with no significant changes in the amplitudes and decay kinetics of sIPSC. The sIPSC inhibition of 5-HT was mimicked by 5-HT1A agonist, 8-OH-DPAT (8-hydroxy-2(di-n-propylamino)tetralin, 10 microM), and blocked by 5-HT1A antagonist WAY-100635 but not by 5-HT1B antagonist SB224289. 5-HT also reduced the frequency of miniature IPSC (mIPSC) (2.59+/-0.51 Hz, control vs. 1.25+/-0.31 Hz, 5-HT, n=16) in similar extent with 5-HT induced reduction of sIPSC frequency (sIPSCs, 55.8+/-6.2%, n=11 vs. mIPSCs, 52.30+/-5.85%, n=16; p>0.5). All together, our results indicate that 5-HT can inhibit presynaptic GABA release via presynaptic 5-HT1A receptors in presympathetic PVN neurons projecting to spinal cord. 相似文献
993.
目的 探讨白细胞介素6(interleukin-6,IL-6)与钙感应性受体(calcium sensing receptor,CASR)基因多态性对青春期女童骨量增长的交互作用.方法 选择228名9-11岁半未月经初潮的健康女童进行两年追踪,采用双能X线骨密度仪检测对象追踪前后全身、左侧近端股骨(包括股骨颈、大转子、粗隆间和华氏三角区)和L1-L4腰椎骨矿含量(bone mineral content,BMC)和骨密度(bone mineral density,BMD),采用聚合酶链反应-限制性片段长度多态性技术检测IL-6-634C/G位点多态性,等位基因特异性突变分离扩增-PCR技术检测CASR A986S位点多态性.结果 176名女童完成整个研究.IL-6基因-634C/G和CASR基因A986S位点多态性与青春期女童骨量增长有关联,IL-6基因-634C/G位点CG+GG基因型女童全身和股骨大转子BMD较CC基因型分别低25.7%和20.6%,CASR基因A986S位点AS+SS基因型女童L1.L4腰椎BMC和华氏三角区BMD增长率较AA基因型分别低14.9%和51.3%,差异有统计学意义(P<0.05).交互作用分析发现,同时具有IL-6基因-634C/G位点G等位基因和CASR基因A986S位点S等位基因的女童,其股骨颈和L1-L4腰椎BMC增长率最低.结论 同时具有IL-6基因-634C/G位点G等位基因和CASR基因A986S位点S等位基因的女童,可能是低骨量增长的危险人群. 相似文献
994.
Guidine PA Rezende GH Queiroz CM Mello LE Prado VF Prado MA Pereira GS Moraes MF 《Neuroscience letters》2008,441(2):201-204
The pilocarpine (PILO) animal model of Temporal Lobe Epilepsy (TLE) portrays the most common changes in hippocampal circuitry found in human TLE. The acute cholinergic insult induces status epilepticus (SE), which triggers an overwhelming set of plastic events that result on late spontaneous recurrent limbic seizures. It has been suggested that the cholinergic system plays an important role in the synchronization required for ictogenesis. We took advantage of a knock-down animal model for the vesicular acetylcholine transporter (VAChT KD) to investigate seizure genesis in a model of cholinergic dysfunction. We induced SE in VAChT KD and wild-type (WT) mice by a single intraperitoneal injection of PILO in order to evaluate susceptibility to seizures. Video-EEG recordings evaluated epileptiform activity and ictal behavior onset. The hypothesis tested is that innate cholinergic hypofunction could result in increased susceptibility to PILO. VAChT KD(HOM) mice showed shorter latency for the first epileptiform discharge and for the first seizure episode, when compared to other groups. The duration of these seizure episodes, however, were not statistically different among experimental groups. On the other hand, VAChT KD(HOM) had the shortest latency to isoelectric EEG, when compared to WT and KD(HET). Our results indicate that a reduction of brain VAChT protein to the levels found in VAChT KD(HOM) mice alters the epileptic response to PILO. Thus, fine-tuning modulation of cholinergic tone can affect the susceptibility of epileptic responses to pilocarpine. 相似文献
995.
目的 检测三种不同来源卵巢癌细胞株中67kD层粘连蛋白受体(67k DLN-R)的表达,探讨其在卵巢癌侵袭转移中的作用。方法 体外培养腹水来源的人卵巢癌细胞株HRA、SKOV3及性实体瘤来源的人卵巢腺癌细胞株3AO。以免疫组化和逆转录-聚合酶链反应技术(RT-PCR)检测各细胞株中67kD LN-R蛋白表达及其mRNA水平。结果 三种细胞的胞膜及胞浆中67kD LN-R蛋白均呈阳性表达,但HRA、SKOV3明显强于3AO细胞,差异有显著性(P均〈0.05);HRA、SKOV3均可见明显的474bp的67kD LN-R特异性条带,其mRNA分别为1.156、1.081;3AO特异性条带极弱,其mRNA为0.358;前两者与后者相比,差异有显著性(P均〈0.05)。结论 67kD LN-R在卵巢癌侵袭转移中发挥重要作用。 相似文献
996.
Mouse mammary tumor virus (MMTV) is a pH-dependent virus that uses mouse transferrin receptor 1 (TfR1) for entry into cells. Previous studies demonstrated that MMTV could induce pH 5-dependent fusion-from-with of mouse cells. Here we show that the MMTV envelope-mediated cell-cell fusion requires both the entry receptor and low pH (pH 5). Although expression of the MMTV envelope and TfR1 was sufficient to mediate low pH-dependent syncytia formation, virus infection required trafficking to a low pH compartment; infection was independent of cathepsin-mediated proteolysis. Human TfR1 did not support virus infection, although envelope-mediated syncytia formation occurred with human cells after pH 5 treatment and this fusion depended on TfR1 expression. However, although the MMTV envelope bound human TfR1, virus was only internalized and trafficked to a low pH compartment in cells expressing mouse TfR1. Thus, while human TfR1 supported cell-cell fusion, because it was not internalized when bound to MMTV, it did not function as an entry receptor. Our data suggest that MMTV uses TfR1 for all steps of entry: cell attachment, induction of the conformational changes in Env required for membrane fusion and internalization to an appropriate acidic compartment. 相似文献
997.
目的 探讨骨髓红系凋亡、增殖状态及促红细胞生成素受体 (EPOR)表达在恶性淋巴瘤贫血发病机理中的意义。方法 以转铁蛋白受体 (CD71)和血型糖蛋白A(GPA)作为红系标志 ,采用流式细胞术检测骨髓红系细胞的凋亡率、增殖率及EPOR的表达。结果 恶性淋巴瘤骨髓红系CD+ 71细胞和GPA+ 细胞凋亡率明显高于正常对照组 ,差异具有非常显著意义 (4 4 .2 8± 2 4.5 2对 11.0 7± 7.16,P <0 .0 0 1和 47.79± 2 8.3 7对 11.3 5± 5 .98,P <0 .0 0 1) ;增殖率也明显高于正常对照组 (4 9.63± 3 1.68对 2 8.47± 13 .63 ,P <0 .0 5和 5 0 .63± 2 8.74对 2 9.5 9± 9.81,P <0 .0 5 ) ;EPOR表达的平均荧光强度 (MFI)低于正常对照组 ,但差异无显著意义 (P >0 .0 5 )。CD+ 71细胞和GPA+ 细胞凋亡率与血红蛋白 (Hb)水平呈一定的负相关 (r =-0 .60 0 9,P <0 .0 5和r =-0 .612 2 ,P <0 .0 5 ) ;EPOR表达与Hb水平无明显相关。结论 红系细胞凋亡率增高可能同恶性淋巴瘤贫血的发病机制有关 ,红系的明显增殖可能是对凋亡的反馈调节。EPOR表达水平降低可能不是恶性淋巴瘤贫血发病的普遍机制。 相似文献
998.
目的 研究成人桥本甲状腺炎及甲状腺腺瘤旁正常甲状腺组织褪黑素受体亚型基因表达的差异及意义。方法 取成人桥本甲状腺炎患者手术切除的甲状腺组织及甲状腺腺瘤瘤旁1. 0cm外正常甲状腺组织,抽提总RNA,合成mt1、MT2 受体引物,用逆转录多聚酶链反应半定量分析褪黑素受体亚型mRNA表达的改变。结果 成人桥本甲状腺炎、甲状腺腺瘤瘤旁正常甲状腺均存在mt1 受体表达,未检测到MT2 受体亚型。桥本甲状腺炎甲状腺组织mt1 受体表达量较正常甲状腺组织明显减少,统计学分析有显著性差异(P<0. 05)。结论 桥本甲状腺炎发病可能与mt1亚型受体抑制有关。褪黑素免疫调节作用可能通过mt1 受体介导。 相似文献
999.
目的 用荟萃分析方法评价toll样受体(TLR)4基因多态性与强直性脊柱炎的关系. 方法 检索在2007年2月前在PubMed及中国期刊全文数据库发表的中英文献.用RevMan 4.2对纳入文献进行荟萃分析,评价合并效应量、功效、异质性及发表偏倚. 结果 共纳入4篇有关Asp299Gly多态位点和3篇Thr399Ile多态位点的病例对照研究.未发现异质性及发表偏倚,合并后功效在80%左右.Asp299Gly位点合并效应量OR=0.94(95%CI:0.66~1.35),Thr399Ile位点合并效应量OR=1.08(95%CI:0.70~1.65). 结论 TLR4基因不是强直性脊柱炎的主要易感基因. 相似文献
1000.
Opioids like morphine produce antinociception after intrathecal administration. Being hydrophilic in nature, morphine also spreads rostrally which leads to respiratory depression. Loperamide has been reported to produce antinociception after both intracisternal and intrathecal administration. It is also hydrophobic, which could restrict its diffusion in the spinal canal. However, the mechanism of its antinociceptive action after intrathecal administration is not definitely known. In the present study, the antinociceptive effect of loperamide was evaluated by the formalin test. It significantly inhibited Phase II flinching behavior. This antinociceptive effect was reversed by pre-administration of naloxone indicating that it was predominantly due to activation of opioid receptors. 相似文献