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口蹄疫DNA疫苗海藻酸钠微球的制备及体外释放的研究 总被引:4,自引:0,他引:4
目的:研制DNA疫苗海藻酸钠微球,并对其体外释药特性进行考察。方法:以口蹄疫DNA疫苗为DNA疫苗的模型药物,采用喷雾干燥一离子交联法制备DNA疫苗海藻酸钠微球;考察粒径大小、外观、载药量等理化特性;考察微球的体外释药特性及其影响因素。结果:微球球形圆整,分散性好,平均粒径为11.9μm,载药量为5%,产率为53.2%。微球的体外释放速率受载药量影响较小,而壳聚糖的交联固化度增高,微球的体外释放速率变慢。结论:以生物降解材料海藻酸钠、壳聚糖,用喷雾干燥法制备DNA疫苗微球,不需要超声和有机溶剂,因而有利于DNA疫苗结构和功能的稳定性;工艺简便,易于工业化生产。 相似文献
135.
目的:建立复方酮替芬喷鼻剂中酮替芬的含量测定方法。方法:采用紫外分光光度法不经分离直接测定酮替芬的含量,检测波长为301nm。结果:酮替芬在浓度为5~30μg/ml内呈线性,相关系数r=0.9999。浓度为7.5、15、30μg/ml的样品液,日内RSD分别为2.68%、1.00%和1.61%,日问RSD分别为2.80%、0.90%和0.81%。浓度为7.5、15、30μg/ml的样品液的平均回收率分别为99.12%、100.25%、99.62%,RSD分别为3.56%、2.10%和1.93%。结论:本方法简便易行,适合复方酮替芬喷鼻剂中酮替芬的含量测定。 相似文献
136.
This paper reports the effects of the H2 antagonist cimetidine on the number of CD4+ and CD8+ cells in nasal mucosa and the IgE level of nasal secretions in patients with allergic rhinitis. The results showed the numbers of CD4+ cells were greater than the numbers of CD8+ cells in nasal mucosa, both in the patients with allergic rhinitis and normal subjects, but the ratio of CD4+ : CD8+ cells was much higher in the patients with allergic rhinitis. After treatment with cimetidine locally for 4 weeks, the numbers of CD4+ cells fell and the numbers of CD8+ cells increased in the patients with allergic rhinitis. The high IgE level of nasal secretion of the patients with allergic rhinitis was much reduced after treatment with cimetidine. The results suggest that there are high numbers of CD4+ cells and lower numbers of CD8+ cells in the nasal mucosa and a high level of IgE in the nasal secretions of the patients with allergic rhinitis. Treatment with cimetidine locally may be of some value to relieve the clinical symptoms of allergic rhinitis. 相似文献
137.
鼻泰治疗变应性鼻炎的实验研究 总被引:6,自引:0,他引:6
鼻泰为治疗变应性鼻炎的中药滴鼻剂。实验表明,该药可抑制大鼠肥大细胞脱颗粒,抑制小鼠皮肤被动过敏反应,抑制实验性变应性鼻炎家兔的鼻粘膜炎症反应并减少其P物质水平。 相似文献
138.
Although the application of a topical local anaesthetic before fibreoptic nasendoscopy is routine practice in many otolaryngological outpatients, the actual benefit to the patient of this procedure remains in doubt. Eighty-two patients were recruited in this double-blind randomized control trial which compared the patients’ experiences of fibreoptic nasendoscopy with nasal preparations of Xylocaine® (lidocaine), normal saline, and no spray to the nose and throat. A visual analogue scoring system was used to determine scores for the overall unpleasantness of procedure, receiving a spray, and taste of the spray, and pain. This study has shown significantly worse overall experience (P = 0.001) and pain (P = 0.048) scores for Xylocaine® spray versus no spray. It is concluded that the routine use of topical local anaesthetics within the nose before routine fibreoptic nasendoscopy is not only of no value, but actually makes the experience worse for the patient. 相似文献
139.
Mucins have a polypeptide backbone, oligosaccharide side-chains and peripheral structures that include sialic acids. Several pathogens have specific receptors for sialic acids, including human strains of influenza A virus which preferentially recognise and bind α2-6 linked rather than α2-3 linked sialic acids.1 1 NElson J., COuceiro S.S., PAulson J.C. & BAum L. (1993) Influenza virus strains selectively recognise sialyloligosaccharides on human respiratory epithelium; the role of the host cell in selection of haemagglutinin receptor specificity. The aim of this study was to identify possible disease-related changes in the expression of sialic acids in nasal mucins. Nasal mucosal samples were placed in organ culture. Metabolically-labelled mucins were purified by gel filtration, blotted on to nitrocellulose membranes and probed with the sialic acid-binding lectins Sambucus nigra and Maackia amurensis. Ninety-five mucosal samples were collected (49 turbinates, 31 nasal polyps, 15 samples from FESS). Lectin binding, expressed as optical density, showed significantly increased binding of S. nigra to cellular (P = 0.02; Kruskal–Wallis) and secreted (P = 0.045) mucin from allergic mucosa compared to non-allergic mucosa. No significant differences were found in the binding patterns of M. amurensis. This study has demonstrated increased expression of α2-6 linked sialic acids in the mucins synthesised and secreted by allergic compared to non-allergic nasal mucosa. This may cause a change in the way mucins and pathogens interact in allergic rhinitis, leading to altered susceptibility to upper respiratory tract infection. 相似文献
140.
目的研究鼻咽癌放射治疗后鼻腔粘连的发病情况、临床特点、诊断、治疗以及预后。方法2000年8月~2003年12月期间收集鼻咽癌放疗后鼻腔粘连60例,男45例,女15例,年龄20岁~65岁,中位年龄为37岁,其中放疗后半年内40例病例在纤维鼻咽镜窥视下行简单分离。结果在放疗后半年内发生鼻腔粘连病例通过简单分离,实现鼻腔再通,效果满意,无1例发生再粘连;超过半年病例经简单分离难以解决。结论鼻咽癌放疗后鼻腔粘连有较高的发生率,多在放疗后6个月内形成,因此鼻腔粘连应早期处理,纤维鼻咽镜下简单分离在早期是一种很有效的方法,而且操作简单,损伤小。 相似文献