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21.
Christoph Gerlinger James Trussell Uwe Mellinger Martin Merz Joachim Marr Ralf Bannemerschult Ilka Schellschmidt Jan Endrikat 《Contraception》2014
Objective
To examine the impact of subject characteristics on efficacy as measured by the Pearl Index (PI) in clinical trials and to make study populations similar by matching.Methods
Our analysis used US data from four large Phase III studies. We compared results from one fertility control patch study with pooled data from three studies with virtually identical design on oral hormonal contraceptives. First, we identified three characteristics that had the most impact on the PI. Second, we used these three variables and matched subjects from the patch study with those from the oral contraceptive (OC) studies. Finally, we calculated the PIs for matched and unmatched subjects from both the patch study and the OC studies.Results
A total of 3706 subjects were included in our analysis. The variables ‘Hispanic ethnicity’, ‘previous pregnancy’ and ‘previous use of hormonal contraceptives’ had the most impact on the PI. The PIs for the matched patch cohort and the matched OC cohort were 2.97 and 2.48, respectively. Those for the unmatched patch cohort and the unmatched OC cohort were 10.17 and 0.90, respectively.Conclusion
Subject characteristics strongly influence the PI in clinical studies of hormonal contraceptives. In particular, Hispanic ethnicity, previous pregnancies and no previous use of hormonal contraceptives result in a higher PI.Implications
PIs from different clinical trials cannot be meaningfully compared unless subject characteristics that have most impact on the PI are similar or are made to be similar statistically as we did here by matching. 相似文献22.
Kristel Kegler Ilka Imbschweiler Reiner Ulrich Peter Kovermann Christoph Fahlke Ulrich Deschl Arno Kalkuhl Wolfgang Baumgärnter Konstantin Wewetzer 《Journal of neural transmission (Vienna, Austria : 1996)》2014,121(6):569-581
Central nervous system (CNS) injury triggers production of myelinating Schwann cells from endogenous oligodendrocyte precursors (OLPs). These CNS Schwann cells may be attractive candidates for novel therapeutic strategies aiming to promote endogenous CNS repair. However, CNS Schwann cells have been so far mainly characterized in situ regarding morphology and marker expression, and it has remained enigmatic whether they display functional properties distinct from peripheral nervous system (PNS) Schwann cells. Potassium channels (K+) have been implicated in progenitor and glial cell proliferation after injury and may, therefore, represent a suitable pharmacological target. In the present study, we focused on the function and expression of voltage-gated K+ channels Kv1–12 and accessory β-subunits in purified adult canine CNS and PNS Schwann cell cultures using electrophysiology and microarray analysis and characterized their antigenic phenotype. We show here that K+ channels differed significantly in both cell types. While CNS Schwann cells displayed prominent K D-mediated K+ currents, PNS Schwann cells elicited K D- and KA-type K+ currents. Inhibition of K+ currents by TEA and Ba2+ was more effective in CNS Schwann cells. These functional differences were not paralleled by differential mRNA expression of Kv1–12 and accessory β-subunits. However, O4/A2B5 and GFAP expressions were significantly higher and lower, respectively, in CNS than in PNS Schwann cells. Taken together, this is the first evidence that CNS Schwann cells display specific properties not shared by their peripheral counterpart. Both Kv currents and increased O4/A2B5 expression were reminiscent of OLPs suggesting that CNS Schwann cells retain OLP features during maturation. 相似文献
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24.
Safa Baris Ilka Schulze Ahmet Ozen Elif Karakoc Aydiner Emel Altuncu Gulsun Tezcan Karasu Nilufer Ozturk Myriam Lorenz Klaus Schwarz Thomas Vraetz Stephan Ehl Isil B. Barlan 《Journal of clinical immunology》2014,34(6):601-606
Purpose
IPEX (Immunodysregulation, Polyendocrinopathy, Enteropathy, X-linked) is a rare X-linked recessive life-threatening disorder characterized by autoimmunity and early death. Pulmonary complication related with IPEX has not been elucidated exactly. Here, we report 4 IPEX patients, 3 of which died from severe pulmonary disease.Methods
Clinical data and laboratory findings including autoantibodies, immunoglobulin levels as well as number of T, B and NK cells were evaluated. FOXP3 expression and T reg activity were analyzed. The FOXP3 gene was sequenced and RNA analysis was performed.Results
Patient I (PI) presented with nephrotic syndrome at 3 years of age and then developed autoimmune hepatitis without eczema, enteropathy or high IgE and died at 9 years of age due to acute respiratory distress syndrome (ARDS). Two cousins of PI had the same hypomorphic splice site mutation leading to a deletion of 27 amino acids, but normal FOXP3 protein expression and normal suppressive capacity of T reg in a proliferation inhibition assay. However, they exhibited typical symptoms such as eczema, diabetes and enteropathy with eosinophilia at early age (PII, PIII) and were transplanted in infancy. One of them had severe respiratory distress right after birth (PIII). Patient IV from another family presented with chronic diarrhea without autoimmune manifestations and died due to ARDS.Conclusion
Lung disease related to IPEX syndrome has not been reported before and this entity could be a critical factor in disease outcome. 相似文献25.
Elizabeth Rabelo-Gonçalves Bruna Roesler Ana Carolina Guardia Arlete Milan Natalicia Hara Cecília Escanhoela Jazon Almeida Ilka Boin José Murilo Zeitune 《Pathology, research and practice》2014
Since Helicobacter spp. DNA was identified in liver tissue resected from patients with hepatocelullar carcinoma (HCC), researchers have suggested a role of this bacterium in hepatic carcinogenesis. Archives of formalin-fixed, paraffin-embedded (FFPE) tissues represent an extraordinary source for clinical studies providing many advantages. However, DNA extraction from FFPE tissues is laborious, time-consuming and still remains a challenge. The aim of this study was to evaluate five protocols for DNA extraction from FFPE liver obtained from patients with HCC in order to detect Helicobacter pylori DNA. These methods were: (1) QIAamp FFPE Tissue Kit, (2) QIAamp DNA Mini Kit, (3) Wizard SV Genomic DNA Purification System, (4) RealiaPrep FFPE gDNA Miniprep System and (5) phenol–chloroform. H. pylori detection was performed using 16S rRNA gene amplification by PCR. The highest total amount of DNA was obtained using the phenol–chloroform method. Analyses of 16S rRNA gene amplification did not show statistically significant differences among the methods (p = 0.466), although the highest percentage of positive cases (70%) was found in samples extracted with phenol-chloroform. We suggest that of the five methods evaluated, phenol/chloroform is the most suitable for detection of H. pylori in FFPE liver from patients with HCC. 相似文献
26.
Key Jana Maletzko Antonia Kohli Aneesha Gispert Suzana Torres-Odio Sylvia Wittig Ilka Heidler Juliana Bárcena Clea López-Otín Carlos Lei Yuanjiu West A. Phillip Münch Christian Auburger Georg 《Neurogenetics》2020,21(3):187-203
neurogenetics - Human RNF213, which encodes the protein mysterin, is a known susceptibility gene for moyamoya disease (MMD), a cerebrovascular condition with occlusive lesions and compensatory... 相似文献
27.
Itamar S. Santos Márcio S. Bittencourt Ilka R.S. Oliveira Angelita G. Souza Danilo P. Meireles Tatjana Rundek Murilo Foppa Daniel C. Bezerra Cláudia M.V. Freire Leonard H. Roelke Sayonara Carrilho Isabela M. Benseñor Paulo A. Lotufo 《Atherosclerosis》2014
Objective
Carotid intima–media thickness (IMT) is a noninvasive measurement of early atherosclerosis. Most IMT studies have involved populations with low rates of racial blending. The aim of the present article is to describe IMT value distributions and analyze the influence of sex and race on IMT values in a large Brazilian sample, a setting with a high rate of racial admixture.Methods
The Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) is a multicenter cohort of 15,105 adult (aged 35–74 years) civil servants in six Brazilian cities. Baseline assessment included IMT measurements in both common carotid arteries. Race was self-reported. We studied the association between sex and race with IMT values using multiple linear regression models. We conducted analyses in all and low-risk individuals, defined as those without classical cardiovascular risk factors.Results
We analyzed complete IMT data from 10,405 ELSA-Brasil participants. We present nomograms by age for all and low-risk individuals, stratified by sex and race. We found that men had significantly higher maximal IMT values compared with women (β = 0.058; P < 0.001). This association remained for low-risk individuals (β = 0.027; P = 0.001). In addition, Brown and White individuals had lower maximal IMT values compared with Black individuals for all (β = −0.034 and β = −0.054, respectively; P < 0.001) and low-risk individuals (β = −0.027; P = 0.013 and β = −0.035; P < 0.001, respectively).Conclusion
We found significantly higher IMT values in men. We found significantly higher IMT values in Black individuals than White and Brown individuals. These results persisted when analyses were restricted to low-risk individuals. 相似文献28.
Regina Selb Vidmante Fuchs Barbara Graf Axel Hamprecht Michael Hogardt Ludwig Sedlacek Roman Schwarz Evgeny A. Idelevich Sören L. Becker Jürgen Held Claus P. Küpper-Tetzel Ilka McCormick-Smith Daniela Heckmann Jasmin Gerkrath Chang-Ok Han Dunja Wilmes Volker Rickerts 《International journal of medical microbiology : IJMM》2019,309(6):151336
Cryptococcosis is a fungal infection of the central nervous system predominantly caused by Cryptococcus neoformans in immunocompromised patients. In several countries worldwide, up to 50% of isolates show in vitro resistance to clinically used antifungals including fluconazole. No prospective data on susceptibility to antifungal drugs are available for Germany. In this study, we characterised all C. neoformans isolates collected from individual patients’ samples at the German reference laboratory for cryptococcosis 2011 and 2017 (n = 133) by multi-locus sequence typing and phenotypic drug susceptibility testing. We identified serotype A/genotype VNI isolates belonging to clonal complexes previously described from Europe, Africa, Asia and South America as the most prevalent agents of cryptococcosis in Germany. Overall, we observed minimal inhibitory concentrations (MICs) above the epidemiological cut-offs (ECVs) in 1.6% of isolates regarding fluconazole and 2.3% of isolates regarding 5-flucytosine. Here, two C. neoformans var. grubii isolates displayed decreased drug susceptibility to fluconazole, one of them additionally to 5-flucytosine. We also found 5-flucytosine MICs above the ECV for two C. neoformans var. neoformans isolates. We identified a novel mutation in the ERG11 gene which might be associated with the elevated fluconazole MIC in one of the isolates. The clinical importance of the detected in vitro resistance is documented by patient histories showing relapsed infection or primary fatal disease. Of note, sertraline demonstrated antifungal activity comparable to previous reports. Systematic collection of susceptibility data in combination with molecular typing of C. neoformans is important to comprehensively assess the spread of isolates and to understand their drug resistance patterns. 相似文献
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