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11.
地塞米松体外诱导宫颈癌细胞株凋亡及其机制的研究 总被引:4,自引:0,他引:4
目的 :研究地塞米松 (Dex)体外能否诱导宫颈癌细胞株 (HeLa细胞 )发生凋亡及其机制。方法 :采用透射电镜、DNALadder、流式细胞仪等方法进行凋亡检测 ,用ECLWesternblot方法检测凋亡过程中相关基因表达的变化。结果 :地塞米松体外作用于HeLa细胞后 ,透射电镜观察到了凋亡小体 ;DNALadder法也检测到了凋亡时DNA降解形成的梯带 ;流式细胞仪检测到了细胞凋亡峰 ,且峰值随着处理时间的延长而增高。在凋亡过程中 ,凋亡相关基因bcl 2表达下调 ,而p5 3基因表达无明显改变。结论 :地塞米松体外能诱导HeLa细胞发生凋亡 ,其机制与bcl 2基因的表达下调有关 相似文献
12.
目的 探讨颈总动脉切除术的适应症和术前准备的一般规律。方法 对我院自1986年~2003年17年问的10例颈总动脉切除术病例进行回顾性分析。其中年龄22~59岁,急诊手术4例,选择性颈动脉切除6例。结果 急诊手术中2例出现中枢神经系统并发症,选择性手术组中1例出现中枢神经系统并发症。除1例因脑转移癌死亡外,随访均健在。结论 行不重建血管的颈总动脉及分歧部切除术,高龄患者须严格掌握适应症,须无脑血管疾病史,术前须进行Matas试验,要有侧支循环建立的客观依据;对年轻患者(30岁以下)可适当放宽手术指征。 相似文献
13.
A nationwide study of intracellular drug metabolite concentrations in children prescribed 6-mercaptopurine for the treatment of lymphoblastic leukaemia was carried out to assess interpatient variability at a standardised dose. Nine children (2% of the total) had completely undetectable metabolites, indicative of non-compliance. Five were adolescents, but otherwise they had no obvious distinguishing characteristics. Not taking any 6-mercaptopurine at all is uncommon, but the problem cannot be predicted. The total number of children who do not comply cannot be determined from this study, but the nine children described represent only a fraction of these. 相似文献
14.
Zhao P Cao J Zhao LJ Qin ZL Ke JS Pan W Ren H Yu JG Qi ZT 《第二军医大学学报》2006,27(5):506-506
The nucleocapsid (N) protein of SARS-coronavirus (SARS-CoV) is the key protein for the formation of the helical nucleocapsid during virion assembly. This protein is believed to be more conserved than other proteins of the virus, such as spike and membrane glycoprotein. In this study, the N protein of SARS-CoV was expressed in Escherichia coli DHSalpha and identified with pooled sera from patients in the convalescence phase of SARS. A plasmid pCI-N, encoding the full-length N gene of SARS-CoV, was constructed. Expression of the N protein was observed in COS1 cells following transfection with pCI-N. The immune responses induced by intramuscular immunization with pCI-N were evaluated in a murine model. Serum anti-N immunoglobutins and splenocytes proliferative responses against N protein were observed in immunized BALB/c mice. The major immunoglobulin G subclass recognizing N protein was immunoglobulin G2a, and stimulated splenocytes secreted high levels of gamma interferon and IL-2 in response to N protein. More importantly, the immunized mice produced strong delayed-type hypersensitivity (DTH) and CD^8+ CTL responses to N protein. 相似文献
15.
Anti‐fibrotic and Anti‐tumorigenic Effects of Rhein,a Natural Anthraquinone Derivative,in Mammalian Stellate and Carcinoma Cells 下载免费PDF全文
Anthraquinone compounds have been recognized to possess antiinflammatory, anti‐fibrotic and anti‐tumour properties and thus applied in human and veterinary therapeutics as active substances of medicinal products. Amongst the anthraquinones isolated from Rheum palmatum, also known as da‐huang, rhein was detected as one of the highest metabolite contents in the bloodstream of mammals. The biological activities of rhein therefore deserve detailed investigation. In this study, we aimed to delineate the mechanism of inhibitory actions of rhein on fibrotic and tumorigenic processes by means of various biochemical assays, such as immunofluorescent staining, real‐time polymerase chain reaction (PCR) and western blotting analyses in rat pancreatic stellate cells (LTC‐14), human pancreatic ductal adenocarcinoma cells (PANC‐1) and human colon carcinoma cells (SW480 and SW620). Our results demonstrated that the application of rhein notably suppressed the mRNA and protein levels of various fibrotic and tumorigenic mediators including alpha‐smooth muscle actin, type I collagen, fibronectin, N‐cadherin and matrix metalloproteinases in the testing mammalian cells. The mechanism of the suppressive actions of rhein was associated with the modulation of the sonic hedgehog and serine‐threonine kinase signalling pathways. In conclusion, we suggest that rhein may serve as a therapeutic or an adjuvant agent in anti‐fibrotic and anti‐tumorigenic approaches. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
16.
Cardiovascular disease (CVD) is a group of diseases affecting the heart and blood vessels and is the leading cause of morbidity and mortality worldwide. Increasingly more evidence has shown that the senescence of vascular endothelial cells is the key to endothelial dysfunction and cardiovascular diseases. Anthocyanin is a type of water-soluble polyphenol pigment and secondary metabolite of plant-based food widely existing in fruits and vegetables. The gut microbiome is involved in the metabolism of anthocyanins and mediates the biological activities of anthocyanins and their metabolites, while anthocyanins also regulate the growth of specific bacteria in the microbiota and promote the proliferation of healthy anaerobic flora. Accumulating studies have shown that anthocyanins have antioxidant, anti-inflammatory, and anti-aging effects. Many animal and in vitro experiments have also proven that anthocyanins have protective effects on cardiovascular-disease-related dysfunction. However, the molecular mechanism of anthocyanin in eliminating aging endothelial cells and preventing cardiovascular diseases is very complex and is not fully understood. In this systematic review, we summarize the metabolism and activities of anthocyanins, as well as their effects on scavenging senescent cells and cardioprotection. 相似文献
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18.
本文对25例头颈部肿瘤患者的外周血NK细胞杀伤活性及NK细胞计数进行测定,其中有15例患者手术治疗切除肿瘤,于术后三周复查NK活性及NK计数,并与正常人组对照。实验结果显示:头颈部肿瘤患者NK活性及NK计数均低于正常人,两组比较均有极显著性差异(P<0.01);术后患者的NK活性比术前有明显提高,配对t检验P<0.01,NK计数比术前也有所提高,配对t检验P<0.05,有显著性差异;NK活性的水平与肿瘤的分期有相关性,晚期(T4期)癌症患者NK活性明显低于早期(T1、T2)患者,可以看出NK活性随着肿瘤的发展而降低,肿瘤对宿主有免疫抑制作用;NK活性与NK数量之间无显著的相关性,二者之间的相关系数r=0.344。 相似文献
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20.
聚焦超声治疗外阴上皮内非瘤样病变的近远期疗效及其影响因素 总被引:11,自引:0,他引:11
目的 探讨聚焦超声治疗外阴上皮内非瘤样病变的近远期疗效及并发症,并初步分析其预后影响因素。方法 选择经病理检查证实为外阴上皮内非瘤样病变患者共76例,采用聚焦超声进行治疗。术后定期随访局部瘙痒症状的改善情况,采用阴道镜检查方法观察体征的变化。结果 聚焦超声治疗后平均随访28.3个月(24~60个月),有39例患者治愈(27例为鳞状上皮增生型,12例为硬化性苔癣型),总治愈率为51%(39/76),总有效率达95%(72/76),累计复发率为36%(26/72)。对复发病例在间隔一段时间后进行再次聚焦超声治疗,同样可以获得显著的临床治疗效果,18例复发后再治疗患者中,6例完全恢复正常,12例症状明显减轻或缓解。76例患者中,4例(2例鳞状上皮增生型,2例硬化性苔癣型)于治疗后2~4h出现治疗区皮肤少量水疱,经抗炎、对症治疗后均痊愈。另有2例(1例鳞状上皮增生型,1例硬化性苔癣型)在治疗后2周出现治疗区局部皮肤浅表溃疡,经抗炎、对症及促表皮生长等治疗3周后痊愈。76例患者经24~60个月的临床观察未发现有远期并发症。不同的麻醉方式及不同的病理类型对聚焦超声治疗效果的影响比较,差异无统计学意义(P〉0.05),但病程越短、年龄越小,聚焦超声治疗的临床效果越好。结论 聚焦超声用于治疗外阴上皮内非瘤样病变安全有效,无远期并发症发生。 相似文献