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171.
ObjectivesMeasures on conventional radiography are used to detect, especially in rheumatoid arthritis, upper cervical spine instabilities (CSIs) with the anterior and posterior atlanto-dental intervals (AADI and PADI) measurements. Our objective was to evaluate the diagnostic performance and reliability of AADIs and PADIs extrapolated based on ratios in assessing anterior atlanto-axial subluxation (aAAS) when plain radiographs do not allow the measures.MethodsRadiographies of 119 patients were randomly selected. Two blinded observers performed two measurements of the odontoid sagittal diameter (O), axis body base sagittal diameter (C2), AADI, PADI, Clark station and Ranawat index, and the AADI/O, AADI/C2, PADI/O and PADI/C2 ratios were calculated. The diagnostic value of AADI and PADI extrapolated from the AADI/O, AADI/C2, PADI/O and PADI/C2 ratios was evaluated using ROC curves, with AADI > 2.9 mm used as the gold standard.ResultsAmong the 119 patients, 12 patients had aAAS (AADI > 2.9 mm), 6 of them had severe aAAS (AADI > 8.9 mm and/or a PADI < 14 mm), and 6 patients had vertical AAS (Clarks station = 2 or 3 and/or Ranawat index < 13 mm). The AADI extrapolated from the AADI/O and AADI/C2 ratios has excellent intra- and inter-observer reproducibility. The diagnostic value of the extrapolated AADI was high for aAAS (sensitivity 92%; specificity of 100%) and severe aAAS (sensitivity75%; specificity 100%). The diagnostic value of the extrapolated PADI was good but lower than the diagnostic value of the extrapolated AADI.ConclusionExtrapolated AADI can be used instead AADI to detect aAAS and severe aAAS.  相似文献   
172.
According to a growing body of research, betrayal by a romantic partner is increasingly considered as a form of interpersonal trauma. Between 30% and 60% of betrayed individuals experience symptoms of post-traumatic stress disorder (PTSD), depression and anxiety to clinically meaningful levels. From a clinical perspective, this constellation of symptoms can be conceptualized as a stressor-related adjustment disorder. Yet, no qualitative research has examined the association between romantic betrayal and traumatic stress from the perspective of betrayed individuals. Face-to-face semi-structured interviews were conducted with 13 participants who had completed a clinical trial for a new treatment for adjustment disorder stemming from betrayal. Data were analysed using thematic content analysis. Although betrayal was experienced as a shocking and destabilizing event, and participants used trauma or ‘feeling traumatized’ as a metaphor to describe their experience, few had constructed their reaction as traumatic stress. In fact, participants reported experiencing difficulties understanding the intensity of their experience. However, when exposed to external sources (e.g., books and interviews by psychologists and researchers) that used a trauma and PTSD framework to explain the effects of betrayal, participants reported feeling clarity, validation and relief. Findings are discussed in the light of theoretical and clinical implications.  相似文献   
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This study evaluated functionalized dextran-derived hydrogels as BMP carriers using both in vitro and in vivo models. In vitro release kinetics indicated that dextran-derived hydrogels could retain rhBMP-2 growth factor in a variable manner depending on their functionalization ratio. The potential of these hydrogels when combined with extracted bovine BMP to enhance the bone formation was evaluated in a rat ectopic model. The largest osteoinduction was found when using hydrogels exhibiting the highest growth factor retention capacity. In addition, some implanted hydrogels demonstrated a capacity to induce an in-vivo calcification certainly related to their chemical composition. These properties make these materials interesting osteoconductive BMP carriers, allowing to decrease the amount of implanted factor required for bone regeneration.  相似文献   
177.
The role of tumour necrosis factor (TNF-alpha) in brain physiology and pathology has been the focus of several studies. However, the source of this lymphokine in the central nervous system and the regulation of its synthesis is still poorly understood. We have therefore used purified astrocytes and brain macrophages in culture to compare the abilities of these two cell types to synthesize TNF-alpha and its mRNA. We find that, in the Swiss mouse, no significant TNF activity or TNF-alpha mRNA are produced by astrocytes, even following activation with lipopolysaccharides (LPS). On the other hand, purified microglial cells express a cytotoxic activity able to kill TNF-sensitive LM cells. Part of this activity is released into the culture medium and part remains bound to the membrane after mild paraformaldehyde treatment, demonstrating the existence in the culture of the soluble and membrane-bound forms of TNF activity. The fact that amoeboid microglial cells, and not astrocytes, are the actual source of TNF in brain cultures was further demonstrated by Northern blot analysis and in situ hybridization using a TNF-alpha specific oligonucleotide probe. The definition of the cell type which, in the CNS, is responsible for TNF synthesis will allow the regulation of this lymphokine to be analysed and opens the way for a better understanding of the interactions between amoeboid microglial cells and the other cell types which make up the nervous system.  相似文献   
178.
目的 探讨多道听觉脑干植入的手术方法及其对恢复双侧听神经瘤所致全聋患者听力的效果。方法  7例双侧听神经瘤患者 ,在肿瘤摘除后将 2 1道听觉脑干植入 (auditorybrainstemimplant,ABI)电极植入于第四脑室外侧隐窝内 ,直接刺激脑干耳蜗核 ,术中以面神经电图、舌咽神经肌电图及电诱发听觉脑干反应 (electricallyevokedauditorybrainstemresponses,EABR)确定电极的正确位置。术后 6周开通装置并调试 ,定期行言语识别能力测试。结果  6例患者术中均能准确定位外侧隐窝 ,并能记录到典型的EABR ;术后均能获得不同程度的言语识别能力 ,其中 2例获得开放句识别能力。另 1例患者术中解剖定位困难 ,术中未能记录到EABR。术后电极刺激 1例无非听觉反应、5例部分电极产生非听觉反应、1例全部电极均产生非听觉反应 ,有非听觉反应的相应电极被关闭。结论 多道听觉脑干植入能使因双侧听神经瘤而全聋的患者产生有意义的听觉 ,术中正确定位脑干耳蜗核为手术成功的关键。  相似文献   
179.
Clémence Jacquin  Emilie Landais  Céline Poirsier  Alexandra Afenjar  Ahmad Akhavi  Nathalie Bednarek  Caroline Bénech  Adeline Bonnard  Damien Bosquet  Lydie Burglen  Patrick Callier  Sandra Chantot-Bastaraud  Christine Coubes  Charles Coutton  Bruno Delobel  Margaux Descharmes  Jean-Michel Dupont  Vincent Gatinois  Nicolas Gruchy  Sarah Guterman  Abdelkader Heddar  Lucas Herissant  Delphine Heron  Bertrand Isidor  Pauline Jaeger  Guillaume Jouret  Boris Keren  Paul Kuentz  Cedric Le Caignec  Jonathan Levy  Nathalie Lopez  Zoe Manssens  Dominique Martin-Coignard  Isabelle Marey  Cyril Mignot  Chantal Missirian  Céline Pebrel-Richard  Lucile Pinson  Jacques Puechberty  Sylvia Redon  Damien Sanlaville  Marta Spodenkiewicz  Anne-Claude Tabet  Alain Verloes  Gaelle Vieville  Catherine Yardin  François Vialard  Martine Doco-Fenzy 《American journal of medical genetics. Part A》2023,191(2):445-458
Chromosome 1p36 deletion syndrome (1p36DS) is one of the most common terminal deletion syndromes (incidence between 1/5000 and 1/10,000 live births in the American population), due to a heterozygous deletion of part of the short arm of chromosome 1. The 1p36DS is characterized by typical craniofacial features, developmental delay/intellectual disability, hypotonia, epilepsy, cardiomyopathy/congenital heart defect, brain abnormalities, hearing loss, eyes/vision problem, and short stature. The aim of our study was to (1) evaluate the incidence of the 1p36DS in the French population compared to 22q11.2 deletion syndrome and trisomy 21; (2) review the postnatal phenotype related to microarray data, compared to previously publish prenatal data. Thanks to a collaboration with the ACLF (Association des Cytogénéticiens de Langue Française), we have collected data of 86 patients constituting, to the best of our knowledge, the second-largest cohort of 1p36DS patients in the literature. We estimated an average of at least 10 cases per year in France. 1p36DS seems to be much less frequent than 22q11.2 deletion syndrome and trisomy 21. Patients presented mainly dysmorphism, microcephaly, developmental delay/intellectual disability, hypotonia, epilepsy, brain malformations, behavioral disorders, cardiomyopathy, or cardiovascular malformations and, pre and/or postnatal growth retardation. Cardiac abnormalities, brain malformations, and epilepsy were more frequent in distal deletions, whereas microcephaly was more common in proximal deletions. Mapping and genotype–phenotype correlation allowed us to identify four critical regions responsible for intellectual disability. This study highlights some phenotypic variability, according to the deletion position, and helps to refine the phenotype of 1p36DS, allowing improved management and follow-up of patients.  相似文献   
180.
Purpose. The concept of Hydrophilic Sphere Stabilization, or Hydrophobic Shielding, has been postulated in the synthesis of biocompatible contrast agents in vascular imaging. To improve the safety of these polyiodinated agents, interactions with protein hydrophobic sites in biomacromolecules should be kept as low as possible. In order to evaluate the level of interactions with proteins, we have selected the serine proteinase Elastase, in presence of Iobitridol (Xenetix®), as a model. Methods. The complex between Iobitridol and Pancreatic Porcine Elastase was investigated by X-ray diffraction techniques, on saturated monocrystals, using the synchrotron radiation at 0.98. Results. In contrast to Iohexol, which displays several interactions including one in the active site, Iobitridol is unable to interact directly with elastase. Only one partially occupied site is found in between two molecules of the crystal packing. Conclusions. The validation of the 'hydrophobic shielding' concept, which was at the origin of the design of the Iobitridol molecule, has been proven to be an essential feature in minimizing in vivo protein interactions.  相似文献   
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