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《The British journal of oral & maxillofacial surgery》2022,60(9):1254-1260
On the 25 March 2020 the Chief Dental Officer (CDO) published guidance to restrict the provision of routine dental care in England due to the rapid spread of the severe acute respiratory syndrome Coronavirus 2 (COVID-19). We analysed the impact of the pandemic on the number of patients presenting with odontogenic pain and infection to the emergency department (ED) of an urban-based teaching hospital, the Bristol Royal Infirmary (BRI). Furthermore, we investigated the severity of infection at first presentation to the ED. The study period encompassed three phases that represented the stages of pandemic restrictions: phase 1 prior to lockdown measures, with no restrictions to dental practice; phase 2 during the government lockdown, with the severest restrictions on dental practices; and phase 3 following the ease of lockdown measures, with return to limited dental services. Data were collected retrospectively from electronic patient records (EPR) regarding adult patients presenting to the ED with dental pain. The rate of presentations (per week) was calculated for each timepoint and compared. A severity score was assigned to each patient using a grading system based on signs of clinical infection and treatment modality. Patients' presentations were analysed at each phase of the pandemic. There was a 42.8% increase in attendance with oral facial pain and infection to ED from phases 1 to 3. The COVID-19 pandemic resulted in restrictions to routine primary dental care services, which were deemed necessary to reduce the spread of the virus. However, this increased demand on secondary care services, as patients increasingly struggled to access primary dental care to manage dental pain. 相似文献
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内生菌由细菌、真菌、古菌和原生生物组成,它们生活在植物的活体组织中,具有丰富的次级代谢产物多样性。人参内生菌在人参的生长发育、次级代谢产物的生成和环境适应等方面均有重要的促进作用,对人参的产量和品质有较大影响。随着人们在微生物领域研究的深入,高通量测序技术已经成为研究植物内生菌的重要方法。文章主要从人参内生菌分离与鉴定研究方法、人参内生菌的多样性、人参内生菌及其次级代谢产物的活性、人参内生菌对宿主的影响等4个方面对人参内生菌近年来的研究进展进行讨论,并对其发展方向提出展望,以期为药用植物内生菌研究和品质改良提供新思路、新方法。 相似文献
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骨质疏松症是一种全身性骨代谢病,由多种因素引起,其特点是骨量、骨密度和骨组织的显微结构恶化,骨脆性增强和易发生骨折。骨质疏松症已严重威胁人类健康,最终将导致患者日常活动减少,生活质量降低,死亡率增加。针对不同的研究对象,选择一个正确、理想的动物骨质疏松的模型和实验方法以尽可能再现人类骨质疏松的状态,是开展动物实验的关键。我们综述了当前原发性和继发性骨质疏松等动物模型的构建,以及利用这些模型进行给药实验的研究方法,并对研发治疗骨质疏松的新型药物的选择提供了一些参考建议,以期对后续关于药物的作用机制、研发新药、药物的改良等研究提供思路。 相似文献
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目的 研究海绵共附生真菌Fusarium equiseti SCSIO 41019的次级代谢产物及抑菌活性。方法 采用中压硅胶柱色谱、中压反相ODS柱色谱及高效液相色谱等方法对发酵产物进行分离和纯化,运用核磁数据及文献对比的方法鉴定化合物结构。采用滤纸片琼脂扩散法、改良肉汤稀释法评价化合物的抑菌活性。结果 从其大米发酵产物中分离并鉴定了8个化合物,分别为equisetin(1)、5'-epiequisetin(2)、lumichrome(3)、N-乙酰基色胺(4)、亚油酸(5)、methyl (4-hydroxyphenyl) acetate(6)、methyl (2-hydroxyphenyl) acetate(7)和graminin B(8)。化合物1、2和5对金黄色葡萄球菌(Staphylococcus aureus)和耐甲氧西林金黄色葡萄球菌(methicillin-resistant Staphylococcus aureus, MRSA)分别具有不同程度的抑制作用,最小抑菌浓度(minimal inhibitory concentration, MIC)为2.0~125μg/mL,其中化合物1的抑菌活性最强(MIC值分别为2.0和3.9μg/mL)。结论 从菌株Fusarium equiseti SCSIO 41019分离得到两个具良好抑菌活性的化合物(1~2),为将其开发为耐甲氧西林金黄色葡萄球菌的先导化合物提供一定参考。 相似文献
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IntroductionOne of the current harm reduction debates in Australia concerns the legalisation of the extended distribution of sterile needles and syringes, a practice that is currently unlawful in most Australian settings.MethodsWe used data from a unique pilot program of authorised extended distribution to document the opinions held by 22 key stakeholders -service staff, drug users and police - about the risks and benefits of authorisation, and to analyse the ways in which drug users were understood within these.ResultsOpinions were strongly in favour of authorising extended distribution, based on the belief that this would reduce the transmission of hepatitis C. However, stakeholders also identified that distributors risked attention from police and some noted that the consequences of this would be borne by distributors themselves and not the services that support them. These opinions rested on specific assumptions about people who inject, some of which reflect negative constructions of drug users as a source of danger to the public or as helpless ‘addicts’ with little control over their risk reduction. But there were other representations that positioned drug users more positively as responsible agents with a strong duty of care to themselves and others whose choices are often limited by inadequate service structures. Staff participants drew on these understandings in careful and strategic ways, arguing for the rationality and expertise of drug users, while also problematizing the individualised approach that any form of authorised extended distribution might take.ConclusionWe argue that localised and incremental changes such as those that took place to support this pilot project, and the extensive support for extended distribution among stakeholders in this study including police, creates meaningful opportunities to think about extended distribution differently, which can in turn support conditions for future discussions about legislative change. 相似文献
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Ghrelin, a brain-gut peptide, has been proven to exert neuroprotection in different kinds of neurological diseases; however, its role and the potential molecular mechanisms in secondary brain injury (SBI) after intracerebral hemorrhage (ICH) are still unknown. In this study, we investigate whether treatment with ghrelin may attenuate SBI in a murine ICH model, and if so, whether the neuroprotective effects are due to the inhibition of nucleotide-binding oligomerization domain-like receptor pyrin domain-containing 3 (NLRP3) inflammasome activation and promotion of nuclear factor-E2-related factor 2 (Nrf2)/antioxidative response element (ARE) signaling pathway. Stereotactically intrastriatal infusion of autologous blood was performed to mimic ICH. Ghrelin was given intraperitoneally immediately following ICH and again 1 h later. Results showed that ghrelin attenuated neurobehavioral deficits, brain edema, hematoma volume, and perihematomal cell death post-ICH. Ghrelin inhibited the NLRP3 inflammasome activation and subsequently suppressed the neuroinflammatory response as evidenced by reduced microglia activation, neutrophil infiltration, and pro-inflammatory mediators release after ICH. Additionally, ghrelin alleviated ICH-induced oxidative stress according to the chemiluminescence of luminol and lucigenin, malondialdehyde (MDA) content, and total superoxide dismutase (SOD) activity assays. These changes were accompanied by upregulation of Nrf2 expression, Nrf2 nuclear accumulation, and enhanced Nrf2 DNA binding activity, as well as by increased expressions of Nrf2 downstream target antioxidative genes, including NAD(P)H quinine oxidoreductase-1 (NQO1), glutathione cysteine ligase regulatory subunit (GCLC), and glutathione cysteine ligase modulatory subunit (GCLM). Together, our data suggested that ghrelin protected against ICH-induced SBI by inhibiting NLRP3 inflammasome activation and promoting Nrf2/ARE signaling pathway. 相似文献
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