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91.
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Christopher J. Moore Melissa C. Caughey Diane O. Meyer Regina Emmett Catherine Jacobs Manisha Chopra James F. Howard Caterina M. Gallippi 《Ultrasound in medicine & biology》2018,44(12):2519-2530
Our group has previously found that in silico, mechanical anisotropy may be interrogated by exciting transversely isotropic materials with geometrically asymmetric acoustic radiation force excitations and then monitoring the associated induced displacements in the region of excitation. We now translate acoustic radiation force-based anisotropy assessment to human muscle in vivo and investigate its clinical relevance to monitoring muscle degeneration in Duchenne muscular dystrophy (DMD). Clinical anisotropy assessments were performed using Viscoelastic Response ultrasound, with a degree of anisotropy reflected by the ratios of Viscoelastic Response relative elasticity (RE) or relative viscosity (RV) measured with the asymmetric radiation force oriented parallel versus perpendicular to muscle fiber alignment. In vivo results from rectus femoris and gastrocnemius muscles of boys aged ~7.9–10.4 y indicate that RE and RV anisotropy ratios in rectus femoris muscles of boys with DMD were significantly higher than those of healthy control boys (RE: DMD?=?1.51 ± 0.87, control?=?0.99 ± 0.69, p?=?0.04, Wilcoxon rank sum test; RV: DMD?=?1.04 ± 0.71, control?=?0.74 ± 0.22, p?=?0.02). In the gastrocnemius muscle, only the RV anisotropy ratio was significantly higher in dystrophic than control patients (DMD?=?1.23 ± 0.35, control?=?0.88 ± 0.31, p?=?0.04). In the dystrophic rectus femoris muscle, the RE anisotropy ratio was inversely correlated (slope?=?–0.03/lbf, r?=?–0.43, p?=?0.07, Pearson correlation) with quantitative muscle testing functional output measures but was not correlated with quantitative muscle testing in the dystrophic gastrocnemius. These results suggest that Viscoelastic Response RE and RV measures reflect differences in mechanical anisotropy associated with functional impairment with dystrophic degeneration that are relevant to monitoring DMD clinically. 相似文献
93.
Association between γ marker,human leucocyte antigens and killer immunoglobulin‐like receptors and the natural course of human cytomegalovirus infection: a pilot study performed in a Sicilian population 下载免费PDF全文
Danilo Di Bona Giulia Accardi Anna Aiello Massimo Bilancia Giuseppina Candore Claudia Colomba Calogero Caruso Giovanni Duro Caterina M. Gambino Luigi Macchia Janardan P. Pandey 《Immunology》2018,153(4):523-531
Natural killer (NK) cells provide a major defence against human cytomegalovirus (HCMV) infection through the interaction of their surface receptors, including the activating and inhibitory killer immunoglobulin‐like receptors (KIRs), and human leucocyte antigen (HLA) class I molecules. Also γ marker (GM) allotypes, able to influence the NK antibody‐dependent cell‐mediated cytotoxicity, appear to be involved in the immunological control of virus infections, including HCMV. In some cases, their contribution requires epistatic interaction with other genes of the immune system, such as HLA. In the present report, with the aim of gaining insight into the immune mechanisms controlling HCMV, we have studied the possible associations among humoral and NK responses, and HCMV infections. In a previous study we assessed whether the KIR and HLA repertoire might influence the risk of developing symptomatic (n = 60) or asymptomatic (n = 60) disease after primary HCMV infection in the immunocompetent host. In the present study, the immunocompetent patients with primary symptomatic HCMV infection were genotyped for GM3/17 and GM23 allotypes, along with the 60 participants with a previous asymptomatic infection as controls. Notwithstanding the presence of missing data record, advanced missing data recovery techniques were able to show that individuals carrying the GM23 allotypes, both homozygous and heterozygous, GM17/17, HLA‐C2 and Bw4T KIR‐ligand groups are associated with the risk of developing symptomatic infection. Our findings on the role of both cellular and humoral immunity in the control of HCMV infection should be of value in guiding efforts to reduce HCMV‐associated health complications in the elderly, including immunosenescence, and in transplantation. 相似文献
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Flavia Persechino Nathalie De Carvalho Silvana Ciardo Barbara De Pace Alice Casari Johanna Chester Shaniko Kaleci Ignazio Stanganelli Caterina Longo Francesca Farnetani Giovanni Pellacani 《Experimental dermatology》2018,27(3):227-232
Pigmented facial macules are common on sun damage skin. The diagnosis of early stage lentigo maligna (LM) and lentigo maligna melanoma (LMM) is challenging. Reflectance confocal microscopy (RCM) has been proven to increase diagnostic accuracy of facial lesions. A total of 154 pigmented facial macules, retrospectively collected, were evaluated for the presence of already‐described RCM features and new parameters depicting aspects of the follicle. Melanocytic nests, roundish pagetoid cells, follicular infiltration, bulgings from the follicles and many bright dendrites and infiltration of the hair follicle (ie, folliculotropism) were found to be indicative of LM/LMM compared to non‐melanocytic skin neoplasms (NMSNs), with an overall sensitivity of 96% and specificity of 83%. Concerning NMSNs, solar lentigo and lichen planus‐like keratosis resulted better distinguishable from LM/LMM because usually lacking malignant features and presenting characteristic diagnostic parameters, such as epidermal cobblestone pattern and polycyclic papillary contours. On the other hand, distinction of pigmented actinic keratosis (PAK) resulted more difficult, and needing evaluation of hair follicle infiltration and bulging structures, due to the frequent observation of few bright dendrites in the epidermis, but predominantly not infiltrating the hair follicle (estimated specificity for PAK 53%). A detailed evaluation of the components of the folliculotropism may help to improve the diagnostic accuracy. The classification of the type, distribution and amount of cells, and the presence of bulging around the follicles seem to represent important tools for the differentiation between PAK and LM/LMM at RCM analysis. 相似文献
97.
Iolanda Borelli Marco A Barberis Francesca Spina Guido C Casalis Cavalchini Caterina Vivanet Luisa Balestrino Monica Micheletti Anna Allavena Paola Sala Carlo Carcassi Barbara Pasini 《European journal of human genetics : EJHG》2013,21(2):154-161
Lynch syndrome is an autosomal-dominant hereditary condition predisposing to the development of specific cancers, because of germline mutations in the DNA-mismatch repair (MMR) genes. Large genomic deletions represent a significant fraction of germline mutations, particularly among the MSH2 gene, in which they account for 20% of the mutational spectrum.
In this study we analyzed 13 Italian families carrying MSH2 exon 8 deletions, 10 of which of ascertained Sardinian origin. The overrepresentation of Sardinians was unexpected, as families from Sardinia account for a small quota of MMR genes mutation tests performed in our laboratory. The hypothesis that such a result is owing to founder effects in Sardinia was tested by breakpoint junctions sequencing and haplotype analyses. Overall, five different exon eight deletions were identified, two of which recurrent in families, all apparently unrelated, of Sardinian origin (one in eight families, one in two families). The c.1277–1180_1386+2226del3516insCATTCTCTTTGAAAA deletion shares the same haplotype between all families and appears so far restricted to the population of South-West Sardinia, showing the typical features of a founder effect. The three non-Sardinian families showed three different breakpoint junctions and haplotypes, suggesting independent mutational events. This work has useful implications in genetic testing for Lynch syndrome. We developed a quick test for each of the identified deletions: this can be particularly useful in families of Sardinian origin, in which MSH2 exon 8 deletions may represent 50% of the overall mutational spectrum of the four MMR genes causing Lynch syndrome. 相似文献
98.
Camnasio S Carri AD Lombardo A Grad I Mariotti C Castucci A Rozell B Riso PL Castiglioni V Zuccato C Rochon C Takashima Y Diaferia G Biunno I Gellera C Jaconi M Smith A Hovatta O Naldini L Di Donato S Feki A Cattaneo E 《Neurobiology of disease》2012,46(1):41-51
Neuronal disorders, like Huntington's disease (HD), are difficult to study, due to limited cell accessibility, late onset manifestations, and low availability of material. The establishment of an in vitro model that recapitulates features of the disease may help understanding the cellular and molecular events that trigger disease manifestations. Here, we describe the generation and characterization of a series of induced pluripotent stem (iPS) cells derived from patients with HD, including two rare homozygous genotypes and one heterozygous genotype. We used lentiviral technology to transfer key genes for inducing reprogramming. To confirm pluripotency and differentiation of iPS cells, we used PCR amplification and immunocytochemistry to measure the expression of marker genes in embryoid bodies and neurons. We also analyzed teratomas that formed in iPS cell-injected mice. We found that the length of the pathological CAG repeat did not increase during reprogramming, after long term growth in vitro, and after differentiation into neurons. In addition, we observed no differences between normal and mutant genotypes in reprogramming, growth rate, caspase activation or neuronal differentiation. However, we observed a significant increase in lysosomal activity in HD-iPS cells compared to control iPS cells, both during self-renewal and in iPS-derived neurons. In conclusion, we have established stable HD-iPS cell lines that can be used for investigating disease mechanisms that underlie HD. The CAG stability and lysosomal activity represent novel observations in HD-iPS cells. In the future, these cells may provide the basis for a powerful platform for drug screening and target identification in HD. 相似文献
99.
Massimo Pandolfo MD Javier Arpa MD Martin B. Delatycki PhD Kim Hanh Le Quan Sang PhD Caterina Mariotti MD Arnold Munnich MD PhD Irene Sanz‐Gallego MD Geneieve Tai BBiomedSC Mark A. Tarnopolsky MD PhD FRCP Franco Taroni MD Michael Spino PharmD Fernando Tricta MD 《Annals of neurology》2014,76(4):509-521
100.
Objective: This was a retrospective study designed to examine the relationship between inpatient neuropsychological status and future utilization costs. Methods: We completed a retrospective chart review of 280 patients admitted to a large academic medical center who were referred for bedside neuropsychological evaluation. Patients were grouped based on neuropsychological recommendation regarding level of supportive needs post-discharge (low, moderate, high). Level of support was used as a gross surrogate indicator of cognitive status in this heterogeneous sample. We also included patients who refused assessment. Outcome variables included time to readmission, number of emergency department visits, inpatient admissions, length of hospitalization, and total costs of hospitalizations, 30 days and 1 year following discharge. Results: Multivariate analysis indicated patients who refused assessment had higher inpatient service utilization (number of ED visits, number of admissions, and total cost of hospitalization) compared to those with moderate needs. Also, high needs patients had higher total cost of hospitalization at 1 year, and those with low needs used the ED more, compared to those with moderate needs. Conclusions: Our findings replicate prior studies linking refusal of neuropsychological evaluation to higher service utilization costs, and suggest a nonlinear relationship between cognitive impairment severity and future costs for medical inpatients (different groups incur different types of costs). Results preliminarily highlight the potential utility of inpatient neuropsychological assessment in identifying patients at risk for greater hospital utilization, which may allow for the development of appropriate interventions for these patients. 相似文献