全文获取类型
收费全文 | 10102篇 |
免费 | 1282篇 |
国内免费 | 256篇 |
专业分类
耳鼻咽喉 | 27篇 |
儿科学 | 37篇 |
妇产科学 | 16篇 |
基础医学 | 508篇 |
口腔科学 | 10篇 |
临床医学 | 353篇 |
内科学 | 321篇 |
皮肤病学 | 12篇 |
神经病学 | 769篇 |
特种医学 | 99篇 |
外科学 | 103篇 |
综合类 | 904篇 |
预防医学 | 121篇 |
眼科学 | 7869篇 |
药学 | 281篇 |
1篇 | |
中国医学 | 188篇 |
肿瘤学 | 21篇 |
出版年
2024年 | 68篇 |
2023年 | 218篇 |
2022年 | 405篇 |
2021年 | 520篇 |
2020年 | 445篇 |
2019年 | 383篇 |
2018年 | 461篇 |
2017年 | 378篇 |
2016年 | 407篇 |
2015年 | 367篇 |
2014年 | 551篇 |
2013年 | 662篇 |
2012年 | 426篇 |
2011年 | 523篇 |
2010年 | 519篇 |
2009年 | 473篇 |
2008年 | 509篇 |
2007年 | 448篇 |
2006年 | 523篇 |
2005年 | 400篇 |
2004年 | 325篇 |
2003年 | 303篇 |
2002年 | 237篇 |
2001年 | 222篇 |
2000年 | 172篇 |
1999年 | 170篇 |
1998年 | 153篇 |
1997年 | 107篇 |
1996年 | 81篇 |
1995年 | 90篇 |
1994年 | 74篇 |
1993年 | 69篇 |
1992年 | 70篇 |
1991年 | 43篇 |
1990年 | 61篇 |
1989年 | 59篇 |
1988年 | 45篇 |
1987年 | 40篇 |
1986年 | 51篇 |
1985年 | 126篇 |
1984年 | 85篇 |
1983年 | 80篇 |
1982年 | 87篇 |
1981年 | 80篇 |
1980年 | 58篇 |
1979年 | 21篇 |
1978年 | 25篇 |
1977年 | 5篇 |
1976年 | 9篇 |
1970年 | 2篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
41.
普南扑灵滴眼剂在视网膜脱离手术中的应用 总被引:3,自引:1,他引:2
目的 探讨普南扑灵滴眼剂在减轻玻璃体视网膜术 (VRS)和巩膜扣带术 (SBS)后炎症反应的作用。方法 将 82例 (82只眼 )随机分为研究组和对照组 ,研究组 41例 (41只眼 ) ,选用 0 .1%普南扑灵滴眼剂点眼 ,对照组 41例 (41只眼 ) ,选用 0 .0 2 5 %地塞米松滴眼剂点眼。观察指标为眼部疼痛、充血、前房闪辉、角膜炎症、虹膜后粘连。结果 选用 0 .1%普南扑灵滴眼剂的研究组在缓解术后眼部疼痛方面及减轻玻璃体切割术后前房闪辉、虹膜后粘连方面优于对照组 ,差异有显著性 (P <0 .0 5~ 0 .0 1)。结论 普南扑灵能显著的减轻 VRS及 SBS后炎症反应。 相似文献
42.
Claudine Savy Fatima Moussafi Jacques Durand Jrme Yelnik Axelle Simon Jeanine Nguyen-Legros 《The Journal of comparative neurology》1995,355(3):392-404
The morphology and distribution of dopaminergic interplexiform cells in adult rat and monkey retinas were analyzed to determine any correlation with the function of dopamine in the outer retinal layers. The retinas were processed as whole mounts for tyrosine hydroxylase immunohistochemistry. There was a network formed by the sclerally directed processes of interplexiform cells in the inner nuclear, outer plexiform, and outer nuclear layers running throughout the retina. Their density was higher in the superior retina than in the inferior retina of the rat and was especially high in the superior temporal quadrant. The external network in this quadrant was significantly less dense in the monkey than in the rat, as are the interplexiform cells. The somata of interplexiform and other dopaminergic cells were about the same size in both rats and monkeys. Computer-assisted reconstruction of external arborizations of individual cells showed that external processes lay very close to horizontal and photoreceptor cells and also to blood capillaries. Because they were long, thin, and highly varicose; branched at right angles; and often arose from an axon hillock, the external processes were identified as axons. Therefore, we define the dopaminergic interplexiform cells as multiaxonal neurons, with at least one outwardly directed axon that reaches the outer plexiform layer. The function of the network of external processes from the interplexiform dopaminergic cells is discussed in terms of modulating the release of dopamine to external layers. 相似文献
43.
Kemal Gündüz Nazmİ Zengİn Süleyman Okudan Mehmet Okka Nİlgün Özbayrak 《Documenta ophthalmologica. Advances in ophthalmology》1995,91(2):155-164
We recorded pattern electroretinograms and visual evoked potentials in a group of selected patients with unilateral uncomplicated branch retinal vein occlusion. To document the effects of preexisting risk factors, patients were divided into three groups: diabetes mellitus, hypertension with hyperlipidemia and no systemic disease. The transient and steady-state pattern electroretinogram and visual evoked potential amplitudes were significantly reduced and visual evoked potential peak times were delayed relative to the fellow eyes and agematched normal subjects. There was a second amplitude reduction relative to the other patient groups in both the affected and fellow eyes of the diabetes mellitus group, which was indicative of an additive effect of diabetes mellitus.Abbreviations BRVO
branch retinal vein occlusion 相似文献
44.
Human gingival keratinocytes were cultured and, after the first passage, subjected to cell detachment assays with polymorphonuclear leucocytes (PMNs) and/or sonic extracts from Actinobacillus actinomycetemcomitans Y4, and Eikenella corrodens 1073. The effector-to-target cell ratio was 30:1. Bacterial extracts alone caused no disruption of keratinocyte monolayers. PMNs alone also caused only minimal detachment after 14 h incubation. Adding A. actinomycetemcomitans to the PMN-keratinocyte co-cultures at the concentration of 100 μg/ml caused dramatic cell detachment. The effect of A. actinomycetemcomitans was heat labile and not inhibited by polymyxin B. Cell detachment was inhibited by α1-antitrypsin, whereas catalase and Superoxide dismutase could not prevent it. No lysis of keratinocytes was observed after incubation, as judged by 51Cr release. E. corrodens had little effect even at the concentration of 1000 μg/ml. H2O2 and partially purified PMN elastase also caused detachment of keratinocytes. These data indicate that PMNs can cause non-lytic detachment of keratinocytes when interacting with certain bacteria. 相似文献
45.
成人原发性肾病综合征患者尿视黄醇结合蛋白的测定及意义 总被引:2,自引:0,他引:2
采用酶联免疫法检测100例正常人及79例成人原发性肾病综合征治疗前后尿视内醇结合蛋白的变化。追踪随访2年,发现经治疗后病理类型为ECPGN,MCN,IgA GN者,尿蛋白及RBP均明显减少,其肾功能不全的发生率较低,而MGN,FSGS,SGN者,尿蛋白及RBP无明显减少,肾功能不全的发生率较高,MsPGN因其增生程度的不同,治疗效果及预后有所不同,轻度增生者治疗效果及预后较好,中,重度增生者,基 相似文献
46.
Retinal projections and visual thalamo-cortical connections were studied in the subterranean mole rat, belonging to the superspecies Spalax ehrenbergi, by anterograde and retrograde tracing techniques. Quantitative image analysis was used to estimate the relative density and distribution of retinal input to different primary visual nuclei. The visual system of Spalax presents a mosaic of both regressive and progressive morphological features. Following intraocular injections of horseradish peroxidase conjugates, the retina was found to project bilaterally to all visual structures described as receiving retinal afferents in non-fossorial rodents. Structures involved in form analysis and visually guided behaviors are reduced in size by more than 90%, receive a sparse retinal innervation, and are cytoarchitecturally poorly differentiated. The dorsal lateral geniculate nucleus, as defined by cyto- and myelo-architecture, cytochrome oxidase, and acetylcholinesterase distribution as well as by afferent and efferent connections, consists of a narrow sheet 3–5 neurons thick, in the dorsal thalamus. Connections with visual cortex are topographically organized but multiple cortical injections result in widespread and overlapping distributions of geniculate neurons, thus indicating that the cortical map of visual space is imprecise. The superficial layers of the superior colliculus are collapsed to a single layer, and the diffuse ipsilateral distribution of retinal afferents also suggests a lack of precise retinotopic relations. In the pretectum, both the olivary pretectal nucleus and the nucleus of the optic tract could be identified as receiving ipsilateral and contralateral retinal projections. The ventral lateral geniculate nucleus is also bilaterally innervated, but distinct subdivisions of this nucleus or the intergeniculate leaflet could not be distinguished. The retina sends a sparse projection to the dorsal and lateral terminal nuclei of the accessory optic system. The medial terminal nucleus is not present. In contrast to the above, structures of the “non-image forming” visual pathway involved in photoperiodic perception are well developed in Spalax. The suprachiasmatic nucleus receives a bilateral projection from the retina and the absolute size, cytoarchitecture, density, and distribution of retinal afferents in Spalax are comparable with those of other rodents. A relatively hypertrophied retinal projection is observed in the bed nucleus of the stria terminalis. Other regions which receive sparse visual input include the lateral and anterior hypothalamic areas, the retrochiasmatic region, the sub-paraventricular zone, the paraventricular hypothalamic nucleus, the anteroventral and anterodorsal nuclei, the lateral habenula, the mediodorsal nucleus, and the basal telencephalon. These results indicate that the apparently global morphological regression of the visual system conceals a selective expansion of structures related to functions of photoperiodic perception and photo-neuroendocrine regulation. We suggest that the evolution of an atrophied eye and reduced visual system is an adaptively advantageous response to the unique subterranean environment. Factors favoring regression include mechanical aspects, metabolic constraints, and competition between sensory systems. The primary advantage of sensory atrophy is the metabolic economy gained by the reduction of visual structures which do not contribute significantly to the animal's fitness. © 1993 Wiley-Liss, Inc. 相似文献
47.
K. M. Saari M.D. 《International ophthalmology》1986,9(1):45-60
To study the inheritance and clinical picture of a new form of vitreoretinal dystrophy I examined 18 family members of a family with six generations. Seven patients, three male and four female, in three consecutive generations were observed to be affected indicating autosomal dominant inheritance. The disease was characterized by juvenile degeneration of the vitreous with detachment of the vitreous body and some floating vitreous opacities, cystoid degeneration of the peripheral retina with whitish glistening stippled areas of superficial retinal degeneration, spotty hyperpigmentation, patches of retinal atrophy with pigmentations, occasional atrophic retinal holes, and in four family members at the age of 4 to 12 years, unilateral or bilateral retinal detachment with breaks in the peripheral retina. Most patients had hyperopia with or without astigmatism. In eyes without detached retina, the disease did not show any marked progression, the lens was clear, the posterior fundus and the retinal and choroidal vessels were normal, and the visual acuity, visual fields, dark adaptation, colour vision, electroretinograms, and visually evoked response findings were normal. 相似文献
48.
Antonio Fea Andrea Grosso Marilena Rabbione Federico Grignolo 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2007,245(2):315-317
Background Optic disc anomalies are frequently associated with Alagille syndrome. We report here the first case of a patient with Alagille
syndrome combined with optic pit and serous macular detachment.
Methods A male patient with Alagille syndrome was referred from the pediatric hepatology department for investigation of visual loss
in the right eye. Anterior segment examination showed evidence of posterior embryotoxon, confirmed by gonioscopic evaluation.
Dilated fundus examination revealed serous macular detachment and optic pit.
Results OCT 3 scans confirmed the clinical findings.
Conclusions Optic pit is uncommon and should prompt a search for genetic disorders or development abnormalities. The association between
the two syndromes in this patient might be due to failure of correct neuroectodermal development, for which a common genetic
pathway is likely. 相似文献
49.
视网膜缺血对兔视神经纤维损害的定量研究 总被引:2,自引:0,他引:2
目的:定量研究视网膜缺血对视神经的损害。方法:通过计算机图像分析定量测算视神经纤维数量;通过前房灌注平衡液,造成超高眼压,形成兔视网膜完全缺血模型,观察视神经纤维数量的变化。结果:正常兔眼平均视神经轴突数为109608±14561(n=22);视网膜缺血眼视神经纤维数量明显减少(P〈0.001)。结论:急性高眼压造成的视网膜缺血可使视神经节细胞及轴突的数量明显减少,应用计算机图像分析可定量检测这种 相似文献
50.