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991.
《Drug testing and analysis》2017,9(10):1490-1498
A new peptide, body protecting compound (BPC), BPC 157, and a variant of mechano‐growth factor (MGF), MGF R23H, were identified in confiscated vials. BPC 157 has the amino acid sequence, GEPPPGKPADDAGLV, and is currently under investigation for the promotion of healing and recovery in a variety of tissues. In vitro metabolism experiments in plasma demonstrate that MGF R23H has good stability and should be detectable in urine, while BPC 157 forms a stable metabolite that should be detectable in urine. A weak cation exchange solid phase extraction method was validated for detection of BPC 157 in urine. The method has a limit of detection of 0.1 ng/mL, precision of less than 20%, and good linearity, r2 0.998. BPC 157 was stable in urine for at least 4 days. The specificity of the method is improved by measurement of a potential BPC metabolite along with the parent peptide. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
992.
Jianrui Ding H. D. Cheng Jianhua Huang Jiafeng Liu Yingtao Zhang 《Journal of digital imaging》2012,25(5):620-627
Breast ultrasound (BUS) image segmentation is a very difficult task due to poor image quality and speckle noise. In this paper, local features extracted from roughly segmented regions of interest (ROIs) are used to describe breast tumors. The roughly segmented ROI is viewed as a bag. And subregions of the ROI are considered as the instances of the bag. Multiple-instance learning (MIL) method is more suitable for classifying breast tumors using BUS images. However, due to the complexity of BUS images, traditional MIL method is not applicable. In this paper, a novel MIL method is proposed for solving such task. First, a self-organizing map is used to map the instance space to the concept space. Then, we use the distribution of the instances of each bag in the concept space to construct the bag feature vector. Finally, a support vector machine is employed for classifying the tumors. The experimental results show that the proposed method can achieve better performance: the accuracy is 0.9107 and the area under receiver operator characteristic curve is 0.96 (p < 0.005). 相似文献
993.
Diabetic mastopathy is the occurrence of lymphocytic mastitis and stromal fibrosis in men as well as women having long-standing diabetes. Clinical and radiological appearance can raise a suspicion of malignancy and result in unnecessary biopsy. As these lesions are known to recur; failure to recognise them can have devastating results. A case of diabetic mastopathy is therefore presented for the knowledge and benefit of all so that unnecessary surgery can be avoided. 相似文献
994.
《Clinical microbiology and infection》2018,24(7):738-743
ObjectivesWe aimed to develop a universal phenotypic method, which allows easy and rapid antimicrobial susceptibility testing independently of underlying resistance mechanisms.MethodsWe established a novel direct-on-target microdroplet growth assay for the detection of antibiotic resistance within a few hours, which is based on matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The microorganisms were incubated with and without meropenem in nutrient broth as microdroplets directly on MALDI-TOF MS target. Subsequently, broth was separated from microbial cells by contacting the microdroplets with an absorptive material. The microorganisms grown in the presence of antibiotic were detected by MALDI-TOF MS. A total of 24 Klebsiella pneumoniae and 24 Pseudomonas aeruginosa isolates were used to assess performance for detection of meropenem resistance. The microdroplet volumes investigated were 2, 4, 6, 8 and 10 μL.ResultsThe best performance was achieved using 6-μL microdroplets. Applying this volume, all growth controls were successfully detected (definition of valid test), and all isolates were correctly categorized as susceptible or non-susceptible after an 18-h incubation. For K. pneumoniae, rate of valid tests, sensitivity and specificity all reached 100% after a 4-h incubation of 6-μL microdroplets. Using the same microdroplet volume for P. aeruginosa, incubation for 5 h resulted in 83.3% of valid tests with 100% sensitivity and 100% specificity.ConclusionsWe demonstrated easy, rapid and accurate resistance detection using carbapenem-resistant Gram-negative bacteria as an example. Our technology is suitable for automatization and expandable to further applications, e.g. simultaneous testing of multiple antibiotics as well as resistance determination directly from clinical samples. 相似文献
995.
996.
Emily E. Brown Yi Zhen Joan Lee Marc K. Halushka Charles Steenbergen Nicole M. Johnson Johana Almansa 《Amyloid》2017,24(2):92-95
Amyloidosis is a group of conditions characterized by the accumulation of amyloid deposits in various tissues. Among these disorders, ATTR amyloidosis occurs either with or without a TTR pathogenic variant. Treatment for amyloidosis depends on the subtype, which is often identified through a tissue biopsy followed by liquid chromatography tandem mass spectrometry (LC–MS/MS). Genetic testing may be done to confirm these results for patients with ATTR amyloidosis; however, the necessity of genetic testing after LC–MS/MS has not been evaluated. A retrospective review identified 153 patients diagnosed with biopsy-proven ATTR amyloidosis, and 56 of these patients underwent both genetic testing and LC–MS/MS. LC–MS/MS and proteomics correctly reported the mutant peptide and heterozygosity in 47/56 (84%) cases. It failed to identify two individuals who were homozygous for the ATTRV122I mutation and failed to detect the following mutations in six other individuals: ATTRA19D, ATTRF44L, ATTRT60A, ATTRI68L and ATTRV122I. Therefore, LC–MS/MS is not sufficient to rule out a pathogenic mutation in cases of ATTR amyloid, and genetic testing should be performed in most cases of ATTR amyloidosis. Correct recognition of hereditary ATTR amyloidosis is important for estimating prognosis, proper familial counselling and guiding use of therapies, such as liver transplantation. 相似文献
997.
姚丽华 《临床超声医学杂志》2017,19(10)
目的 探讨弹性定量参数在临床触诊阴性乳腺病(non-palpablebreast lesions,NPBL)中的诊断价值。方法 选取2013年1月-2015年6月在我院行高频超声并经手术病理证实的NPBL患者。依照手术后病理结果分为良性病灶组(A组,n=110),恶性病灶组(B组,n=40)。分别比较并分析两组弹性应变率(SR)比值、直径变化率、面积比及二维超声检查。应用受试者操作特性曲线(ROC)曲线分析SR比值、直径变化率、面积比、二维超声及三种弹性定量参数联合诊断乳腺癌的ROC曲线下面积(AUC)、最佳界值、敏感度和特异度。结果B组SR水平(6.04±2.53)显著高于A组水平(2.86±1.51),差异有统计学意义(t=5.031;p=0.000)。根据两组SR水平制作ROC曲线,AUC为0.844,以5.22作为最佳界值,诊断乳腺癌的敏感度为57.5%,特异度为96.4%。B组病灶的直径变化率(0.28±0.12)显著高于A组(0.17±0.09),同时面积比(1.96±0.28)亦显著高于A组(1.12±0.33)(p值均<0.05)。通过SR、直径变化率、面积比水平联合诊断乳腺癌,敏感度为77.5%,特异度为94.5%,AUC为0.937,高于单项指标。结论 通过三种弹性定量参数联合诊断能够提高对乳腺癌的诊断能力。 相似文献
998.
Sabrina Gioria Hubert Chassaigne Donatella Carpi Antonietta Parracino Stefania Meschini Paola Barboro François Rossi 《Toxicology letters》2014
Although gold nanoparticles (AuNPs) are currently used in several industrial products and biomedical applications, information about their biological effects is very limited. Thus, it is becoming crucial to assess their safety and adequately investigate the complexity of cell–nanoparticles interactions. In this work, the Balb/3T3 mouse fibroblast cell line was selected as an in vitro model to study the effects of AuNPs. Alteration of cellular processes and biochemical pathways caused by AuNPs exposure was investigated by analysing the differentially expressed proteome. Of interest was the difference observed in the protein pattern expression of cells exposed to AuNPs. It was found that 88 and 83 proteins were de-regulated after exposure to 5 and 15 nm AuNPs, respectively. Analysis of the proteome revealed that AuNPs triggers several pathways related to cellular growth and proliferation, cell morphology, cell cycle regulation, cellular function and maintenance, oxidative stress, and inflammatory response. Moreover, SPR analysis showed an increase of ECM proteins biosynthesis in cells exposed to AuNPs. We observed by TEM analysis that NPs are internalized and confined mainly in autophagosomes. Endoplasmic reticulum stressed and modification at mitochondrial level occurred. This study aims to improve existing knowledge necessary for a correct assessment of the balance between AuNPs potential adverse and beneficial effects and might have important implications for biomedical applications (e.g. nanomedicine). 相似文献
999.
1000.