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1.
我国奶牛养殖规模不断扩大,奶业产值比重逐步提高,给奶牛疫病防治带来巨大压力。奶牛乳房炎及细菌性肺炎等呼吸系统疾病和细菌性肠炎等消化系统疾病最为常见,抗菌药物的使用成为主要防治手段。但抗菌药物的不当使用易使细菌产生耐药性,增加临床治疗的成本和难度,危害我国奶牛产业发展。本文对截至2021年7月我国和美国、英国、日本、欧盟批准用于奶牛的抗菌药物产品进行整理、统计与分析,包括抗菌药物的分类、剂型以及适应证等,旨在为我国奶牛用抗菌药物管理、合理用药和新兽药开发提供参考。 相似文献
2.
Anna Maria Spera 《World Journal of Virology》2022,11(5):275-282
With a 5.3% of the global population involved, hepatitis B virus (HBV) is a major public health challenge requiring an urgent response. After a possible acute phase, the natural history of HBV infection can progress in chronicity. Patients with overt or occult HBV infection can undergo HBV reactivation (HBVr) in course of immunosuppressive treatments that, apart from oncological and hem-atological diseases, are also used in rheumatologic, gastrointestinal, neurological and dermatological settings, as well as to treat severe acute respiratory syndrome coronavirus 2 infection. The risk of HBV reactivation is related to the immune status of the patient and the baseline HBV infection condition. The aim of the present paper is to investigate the risk of HBVr in those not oncological settings in order to suggest strategies for preventing and treating this occurrence. The main studies about HBVr for patients with occult hepatitis B infection and chronic HBV infection affected by non-oncologic diseases eligible for immunosuppressive treatment have been analyzed. The occurrence of this challenging event can be reduced screening the population eligible for immunosuppressant to assess the best strategies according to any virological status. Further prospective studies are needed to increase data on the risk of HBVr related to newer immunomodulant agents employed in non-oncological setting. 相似文献
3.
Valproic acid (VPA) is an anti-seizure drug that causes idiosyncratic liver injury. 2-propyl-4-pentenoic acid (Δ4VPA), a metabolite of VPA, has been implicated in VPA-induced hepatotoxicity. This review summarizes the pathogenesis involved in VPA-induced liver injury. The VPA induce liver injury mainly by i) liberation of Δ4VPA metabolites; ii) decrease in glutathione stores and antioxidants, resulting in oxidative stress; iii) inhibition of fatty acid β-oxidation, inducing mitochondrial DNA depletion and hypermethylation; a decrease in proton leak; oxidative phosphorylation impairment and ATP synthesis decrease; iv) induction of fatty liver via inhibition of carnitine palmitoyltransferase I, enhancing nuclear receptor peroxisome proliferator-activated receptor-gamma and acyl-CoA thioesterase 1, and inducing long-chain fatty acid uptake and triglyceride synthesis. VPA administration aggravates liver injury in individuals with metabolic syndromes. Therapeutic drug monitoring, routine serum levels of transaminases, ammonia, and lipid parameters during VPA therapy may thus be beneficial in improving the safety profile or preventing the progression of DILI. 相似文献
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5.
美国食品药品管理局(FDA)于2022年7月发布了"治疗等效性评价供企业用指导原则"(草案)。该指导原则阐明了FDA治疗等效性的标准以及治疗等效性编码系统,目的是准确评价仿制药与参比制剂的治疗等效性并通过治疗等效性代码,在"橙皮书"中迅速检索到治疗等效的仿制药。而中国目前尚无类似的指导原则,详细介绍FDA该指导原则主要内容,期望对中国加强仿制药的治疗等效性评价和加速完善和实施符合国情的治疗等效性编码系统有所帮助。 相似文献
6.
目的 通过对消化系统常见肿瘤的突变基因进行分析,建立抗肿瘤药物新靶点的成药性评估方法。方法 搜集Integrative Onco Genomics数据库中5种消化系统常见肿瘤(食管癌、胃癌、结直肠癌、肝癌以及胰腺癌)的突变基因数据,从中筛选出各肿瘤中突变率较高的基因,通过canSAR数据库对这些基因或其编码的蛋白进行成药性评估,找到可用于抗肿瘤新药开发的潜在靶点。结果 本研究搜集了5种肿瘤共计35个队列,5445个肿瘤样品。选择每个肿瘤突变率排名前10的基因进一步分析,使用canSAR数据库对未公开研究的突变基因或其编码的蛋白质进行成药性分析,共筛选到17个可成药的潜在药物治疗靶点。结论 本研究建立了一种基于突变基因或其编码蛋白的靶点成药性评估方法,该方法的运用能够为寻找新的抗肿瘤药物治疗靶点提供参考,节省新药开发中靶点筛选的成本与时间。 相似文献
7.
糖尿病肾病(DKD)是我国慢性肾脏病的主要原因之一,给社会公共卫生和患者的生存质量造成了巨大的影响。最近颁布的多项指南更新了有关DKD治疗与管理的建议,新型降糖药物为DKD的防治提供了新的选择。中医药干预DKD历史悠久,相关理论不断发展和完善。随着循证医学在中医药研究中的应用和增加,中医药干预DKD在缓解患者乏力、水肿、腰酸等症状,减少尿蛋白水平和保护肾功能,提高治疗有效率,降低终末期肾脏病的发生风险,改善疾病长期预后等方面的疗效逐渐被认可和重视。本文就近年来中西医有关DKD的治疗进展和优势进行总结及分析。 相似文献
8.
《Drug discovery today》2022,27(6):1724-1732
The enactment of orphan drug-specific legislation pioneered by the USA was subsequently followed by many regions, including the European Union (EU), Australia, Japan, and Taiwan. Here, we discuss the associated regulations established and their impacts in the aforementioned regions, which are among the first with frameworks specific for orphan drugs. Varied scopes of rare diseases or orphan drugs, diverse incentives, and heterogeneous types of reimbursement systems imply the prioritization of the agencies concerned. The numbers of designated and approved drugs reflect the impact of the regulatory and reimbursement frameworks. A comparison of the frameworks and their impact in the respective regions could provide valuable information for developing and improving related frameworks for countries worldwide. 相似文献
9.
In the field of drug development, technology for producing human metabolites at a low cost is required. In this study, we explored the possibility of using prokaryotic water-soluble cytochrome P450 (CYP) to produce human metabolites. Streptomyces griseolus CYP105A1 metabolizes various non-steroidal anti-inflammatory drugs (NSAIDs), including diclofenac, mefenamic acid, flufenamic acid, tolfenamic acid, meclofenamic acid, and ibuprofen. CYP105A1 showed 4′-hydroxylation activity towards diclofenac, mefenamic acid, flufenamic acid, tolfenamic acid, and meclofenamic acid. It should be noted that this reaction specificity was similar to that of human CYP2C9. In the case of mefenamic acid, another metabolite, 3′-hydroxymethyl mefenamic acid, was detected as a major metabolite. Substitution of Arg at position 73 with Ala in CYP105A1 dramatically reduced the hydroxylation activity toward diclofenac, flufenamic acid, and ibuprofen, indicating that Arg73 is essential for the hydroxylation of these substrates. In contrast, substitution of Arg84 with Ala remarkably increased the hydroxylation activity towards diclofenac, mefenamic acid, and flufenamic acid. Recombinant Rhodococcus erythrocyte cells expressing the CYP105A1 variant R84A/M239A showed complete conversion of diclofenac into 4′-hydroxydiclofenac. These results suggest the usefulness of recombinant R. erythropolis cells expressing actinomycete CYP, such as CYP105A1, for the production of human drug metabolites. 相似文献
10.