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81.
Mapping of murine YACs containing the genesCea2 andCea4 after B1-PCR amplification and FISH-analysis
G. Rettenberger W. Zimmermann C. Klett U. Zechner H. Hameister 《Chromosome research》1995,3(8):473-478
PCR with primers specific for the murine B1 consensus sequence allows amplification of DNA from murine sources. We have used B1-PCR for amplifying yeast artificial chromosome (YAC) DNA which can be used to localize single YACs by fluorescencein situ hybridization. The genes for the pregnancy-specific glycoproteins Cea2 and Cea4, both belonging to the large carcinoembryonic antigen gene family, were localized by chromosomalin situ suppression hybridization of three YAC clones to murine chromosome 7A2-A3. This was facilitated by the use of the mouse lymphoma cell line WMP/WMP which contains nine pairs of Robertsonian fusion chromosomes. 相似文献
82.
Electrocardiological profile and proarrhythmic effects of quinidine,verapamil and their combination: a mapping study 总被引:2,自引:0,他引:2
S. Dhein M. Schott E. Gottwald W. Klaus 《Naunyn-Schmiedeberg's archives of pharmacology》1995,353(1):94-101
Quinidine and verapamil are widely used as antiarrhythmic agents and their combination is often used in the treatment of supraventricular tachycardia. This study was undertaken to clarify, whether these drugs exert proarrhythmic effects on the ventricles in therapeutic concentrations and whether possible arrhythmogenic effects might be enhanced by combination. Isolated rabbit hearts perfused according to the Langendorff technique were treated with increasing concentrations of quinidine (0.05 to 3.5 M) or verapamil (5 to 50 M) or of their combination (70:1 or 10:1; quinidine:verapamil) corresponding to common low, medium and high free therapeutic concentrations. The epicardial activation process was measured using a computer assisted mapping system for unipolar multichannel recording (256 channels simultaneously).Both substances prolonged the atrioventricular conduction time PQ. This effect was even more pronounced if the 70:1 combination was administered. The activation pattern was altered by both drugs and their combination to the same extent as became obvious from analysis of local activation vectors and of localisation of breakthroughpoints of epicardial activation for heart beats under control conditions and under drug treatment. The epicardial potential durations were prolonged by quinidine and to the same degree by the combinations, but not by verapamil alone. The total activation time was prolonged under the influence of quinidine and if the 70:1 combination was given. Both substances exerted a negative inotropic effect which was enhanced in an additive manner if both drugs were combined. In parallel the coronary flow was diminished.From these results it is concluded that (1) in this therapeutic concentration range quinidine possess a greater proarrhythmic risk than verapamil, (2) that both drugs' PQ prolonging effect can be enhanced by combination, (3) that combination does not enhance the proarrhythmic effects but the negative inotropic effects. 相似文献
83.
Jeffrey M. Trent Barbara Weber X. Y. Guan Ji Zhang Francis Collins Ken Abel Austin Diamond Paul Meltzer 《Breast cancer research and treatment》1995,33(2):95-102
Summary The recognition of recurring sites of chromosome changes in malignancies has greatly facilitated the identification of genes implicated in the pathogenesis of human cancers. Based especially upon recent studies [1–4], it appears increasingly likely that a subset of recurring chromosome alterations will be recognized in human breast cancer. Currently recognized chromosome changes characterizing breast carcinoma include the recognition of cytologic features of gene amplification (e.g. double minutes [dmins] and homogeneously staining regions [HSRs]) [5–8]. As these and other chromosome regions are implicated in recurring abnormalities in breast cancer, it will become increasingly important to have band-or region-specific genomic libraries and probes in order to facilitate high resolution physical mapping and ultimately to clone breast cancer related genes [9]. Toward this end an important recent development in physical mapping has been the establishment of chromosome microdissection as a rapid and reproducible approach to rapidly isolate and characterize chromosome region-specific DNA, greatly facilitating the initial steps in positional cloning of disease-related genes [10–13]. In this brief report, we will highlight the application of chromosome microdissection to the generation of region-specific probes for both fluorescent in situ hybridization (FISH) and the generation of genomic microclone libraries. Additionally, efforts using this methodology to generate a microclone library encompassing the early onset breast/ovarian cancer (BRCA1) gene will be presented.Presented by Jeffrey M. Trent at the 16th Annual San Antonio Breast Cancer Symposium, San Antonio TX, USA, November 4, 1993; Minisymposium on Molecular Genetics in Breast Cancer. 相似文献
84.
采用91 导联体表电位标测法( B S P M) 观察80 例正常人 Q Tpd( Q 波起点到 T 波峰值间期的离散度) ,与同步12 导联心电图 Q T 离散度( Q Td) 对照,探讨 B S P M 条件下测定 Q Td 的可行性。结果:① Q Tp 、 Q Tpd 、 Q Tpc1d( Bazzett 公式校正) 、 Q Tpc2d( Fridercia 公式校正) 分别为(292 .69 ±37 .75) ms 、(36 .77 ±7 .40) ms 、(40 .23 ±9 .04) ms 和(40 .11 ±7 .73) ms ;② Q Tpd 与 Q Td 、 Q Tpc1d 与 Q Tc1d 、 Q Tpc2d 与 Q Tc2d 有良好的相关性;③3 个年龄组(18 ~35 岁、36 ~60 岁、61 ~70 岁) 各参数间无显著性差异;④ Q Tp 女性明显大于男性( P< 0 .05) ,其余各值男女性之间均无显著性差异。提示: B S P M 测定 Q Tpd 简便可行、较为准确,正常值可暂定为52 ms 。 相似文献
85.
Intra-Operative Direct Electrical Stimulations of the Central Nervous System: The Salpêtrière Experience With 60 Patients 总被引:6,自引:0,他引:6
Duffau H Capelle L Sichez J Faillot T Abdennour L Law Koune JD Dadoun S Bitar A Arthuis F Van Effenterre R Fohanno D 《Acta neurochirurgica》1999,141(11):1157-1167
Indications of surgical treatment for lesions in the central nervous system depend on the risk of a definitive neurological deficit, related to the benefit of resection. Detection of eloquent areas is then necessary because of major individual variability. Neuro-imaging functional techniques are in development and are beginning to be efficient for cortical sensorymotor mapping, but still lack sensitivity and specificity for language mapping, and remain unable to give real-time data during surgery and to perform sub-cortical mapping. The more precise and reliable method of functional mapping is represented by the intra-operative direct electrical stimulations (DES), which allow identification and preservation of essential pathways for motricity, sensibility and language, at each level of the central nervous system (cortico-subcortical). We report our experience of DES in the surgery of tumours and vascular malformations located in supra-tentorial brain eloquent areas, with a consecutive series of 60 patients operated on under general or local anaesthesia, from November 1996 until May 1999 in our department at La Salpêtrière Hospital. Presenting symptoms in the 60 subjects (39 males, 21 females, mean age: 45 years) were seizures in 37 cases with normal clinical examination, and mild neurological deficit in 29 cases. MRI showed 60 supra-tentorial brain lesions: 30 precentral, 12 postcentral, 14 perisylvian in the dominant hemisphere, 4 deep-seated. All subjects underwent surgical resection using DES, with supratentorial cortico-subcortical mapping under general anaesthesia for motor areas detection in 43 cases and under local anaesthesia for sensori-motor and/or language tasks in 17 cases. The final histological diagnosis was 44 gliomas (31 low-grade and 13 high-grade), 9 metastasis, 3 cavernomas, 4 arteriovenous malformations (AVM). Resection was total or subtotal in 52 cases (87%) and partial in 8 cases (13%). 29 patients had no post-operative deficit, while the other 31 patients were impaired post-operatively, with in all cases, except 3, a complete recovery delayed for 15 days to 3 months (overall morbidity: 5%). The median follow up was 14 months. Intra-operative direct electrical stimulations of the central nervous system constitute a reliable, precise and safe method, allowing the realization of a functional mapping useful for all operations of lesions located in eloquent areas. This technique allows a minimization of definitive post-operative neurological deficit, and concurrently an improvement in the quality of resection. 相似文献
86.
In binding assays, both dynorphin B and alpha-neoendorphin are relatively selective for the kappa1b site, unlike U50,488H which has high affinity for both kappa1a and kappa1b sites. In vivo, U50,488H, dynorphin B and alpha-neoendorphin analgesia are reversed by the kappa1-selective antagonist, nor-binaltorphimine (norBNI). Antisense mapping the three exons of KOR-1 revealed that probes targeting all three exons blocked U50,488H analgesia, as expected. However, the selectivity profile of dynorphin B and alpha-neoendorphin analgesia towards the various antisense oligodeoxynucleotides differed markedly from U50,488H, implying a different receptor mechanism of action. 相似文献
87.
Scopolamine Effects on Visual Information Processing, Attention, and Event-Related Potential Map Latencies 总被引:6,自引:0,他引:6
Daniel Brandeis Hilary Naylor Roy Halliday Enoch Callaway Lovelle Yano 《Psychophysiology》1992,29(3):315-335
We measured performance and event-related brain potential (ERP) map latencies in 12 subjects during four visual discrimination tasks to compare the timing of scopolamine effects on information processing and attention. "Topographic component recognition" found ERP map latencies at times of best fit with a component model map. This "common topography" criterion minimized topographic differences among conditions to facilitate latency interpretations. Scopolamine slowed N1 latency in all tasks, and P3 and reaction time in some tasks. The drug delayed responses to easy targets more than to hard targets. It also induced a disproportionate N1 delay for unilateral high spatial frequency gratings. Both effects reflect a scopolamine-induced impairment when processing targets that usually capture attention. Scopolamine also impaired accuracy for unilateral high spatial frequency gratings, and for gratings presented at probable locations, confirming and extending previous findings. Scopolamine-induced P1 and N1 delays showed that visual processing was affected. Several results were inconsistent with a serial stage model. We suggest that scopolamine both delays selected processes and impairs a processing mode based on automatic capture of attention, inducing more serial processing. 相似文献
88.
This study identifies brain regions participating in the execution of eye movements for voluntary positive accommodation (VPA) during open-loop vergence conditions. Neuronal activity was estimated by measurement of changes in regional cerebral blood flow (rCBF) with positron emission tomography and 15O-water. Thirteen naive volunteers viewed a checkerboard pattern with their dominant right eye, while a lens interrupted the line of gaze during alternate 1.5 s intervals. Three counterbalanced tasks required central fixation and viewing of a stationary checkerboard pattern: (i) through a 0.0 diopter (D) lens; (ii) through a -5.0-D lens while avoiding volitional accommodation and permitting blur; and (iii) through a -5. 0-D lens while maintaining maximal focus. The latter required large-amplitude, high-frequency VPA. As an additional control, seven of the subjects viewed passively a digitally blurred checkerboard through a 0.0-D lens as above. Optometric measurements confirmed normal visual acuity and ability to perform the focusing task (VPA). Large-amplitude saccadic eye movements, verified absent by electro-oculography, were inhibited by central fixation. Image averaging across subjects demonstrated multifocal changes in rCBF during VPA: striate and extrastriate visual cortices; superior temporal cortices; and cerebellar cortex and vermis. Decreases in rCBF occurred in the lateral intraparietal area, prefrontal and frontal and/or supplementary eye fields. Analysis of regions of interest in the visual cortex showed systematic and appropriate task dependence of rCBF. Activations may reflect sensorimotor processing along the reflex arc of the accommodation system, while deactivations may indicate inhibition of systems participating in visual search. 相似文献
89.
目的 探讨舌及口底鳞癌淋巴转移的手术时机与方式对预后的影响。方法 舌及口底鳞癌67例,非手术组12例(为cN_(2~3)患者),手术组55例。cN_028例行原发灶切除,其中23例行选择性颈淋巴清扫。27例cN_(1~3)(cN15例、cN_(2~3)22例)行原发灶切除加根治性颈淋巴清扫,其中16例cN_(2~3)行岛状肌皮瓣修复术:结果 在34例患者中(cN_(2~3)),手术组5年生存率为54.55%(12/22),非手术组5年生存率为41.67%(5/12)。28例cN_0患者中,4例单纯癌肿切除者术后45~60天出现淋巴转移;23例行选择性颈淋巴结清扫术者,证实13例有隐匿性淋巴结转移,10例未见淋巴结转移。结论 对cN_0患者应尽早行选择性颈淋巴结清扫术。对多区域淋巴结或一个区域多个淋巴结转移的cN_(2~3)患者,手术比非手术组的生存率更高,但后者对提高5年生存质量有一定作用。 相似文献
90.
喉鳞癌瘤内微血管及微淋巴管形态计量研究及临床意义 总被引:2,自引:0,他引:2
目的:研究喉鳞癌瘤内微血管和微淋巴管形态、分布、密度,以及相关临床意义。方法:采用5’-Nase-AlPase双重酶组织化学法和HE染色对40侧喉鳞癌标本冰冻切片进行研究。结果:光镜下微血管呈蓝色,微淋巴管呈棕色。除转移组微血管密度显著高于未转移组外,与其余临床指标均未见相关性。结论:瘤内微血管密度与淋巴转移有明显相关,而微淋巴管密度未发现明显临床意义,其机制待深入研究。 相似文献