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91.
Endoglin (CD 105, TGF-β receptor III) is a homodimeric transmembrane glycoprotein that plays a regulatory role in TGF-β signaling. Its functional role in the context of atherosclerosis has yet to be defined and should be stated here. Therefore, we focused on the role of endoglin in atherosclerosis in both humans and experimental animals. Endoglin expression was demonstrated in atherosclerotic vessels predominantly in endothelial cells and smooth muscle cells in various types of blood vessels in mice and humans, suggesting its participation in atherogenesis. Endoglin expression was also related to the expression of eNOS in endothelium, repair of the vessel wall, plaque neoangiogenesis, production of collagen and stabilization of atherosclerotic lesions. In addition, increased levels of soluble endoglin were associated with hypercholesterolemia, atherosclerosis, acute myocardial infarction and were related to inhibition of TGF-β signaling in the vessel wall. Moreover, soluble endoglin levels were significantly lowered after a series of extracorporeal eliminations in patients with familial hypercholesterolemia. Additionally, statin treatment decreased levels of soluble endoglin and increased its expression in aorta, which was related to reduced atherosclerosis in mice. In conclusion, we propose that measurement of soluble endoglin might give information about progression of the atherosclerotic process or the efficacy of therapeutic interventions, which is the task that must be answered in clinical trials. 相似文献
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93.
Koštál V Šimek P Zahradníčková H Cimlová J Štětina T 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(9):3270-3274
Among vertebrates, only a few species of amphibians and reptiles tolerate the formation of ice crystals in their body fluids. Freeze tolerance is much more widespread in invertebrates, especially in overwintering insects. Evolutionary adaptations for freeze tolerance are considered to be highly complex. Here we show that surprisingly simple laboratory manipulations can change the chill susceptible insect to the freeze tolerant one. Larvae of Drosophila melanogaster, a fruit fly of tropical origin with a weak innate capacity to tolerate mild chilling, can survive when approximately 50% of their body water freezes. To achieve this goal, synergy of two fundamental prerequisites is required: (i) shutdown of larval development by exposing larvae to low temperatures (dormancy) and (ii) incorporating the free amino acid proline in tissues by feeding larvae a proline-augmented diet (cryopreservation). 相似文献
94.
Veits J Weber S Stech O Breithaupt A Gräber M Gohrbandt S Bogs J Hundt J Teifke JP Mettenleiter TC Stech J 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(7):2579-2584
High-pathogenic avian influenza viruses (HPAIVs) evolve from low-pathogenic precursors specifying the HA serotypes H5 or H7 by acquisition of a polybasic HA cleavage site. As the reason for this serotype restriction has remained unclear, we aimed to distinguish between compatibility of a polybasic cleavage site with H5/H7 HA only and unique predisposition of these two serotypes for insertion mutations. To this end, we introduced a polybasic cleavage site into the HA of several low-pathogenic avian strains with serotypes H1, H2, H3, H4, H6, H8, H10, H11, H14, or H15, and rescued HA reassortants after cotransfection with the genes from either a low-pathogenic H9N2 or high-pathogenic H5N1 strain. Oculonasal inoculation with those reassortants resulted in varying pathogenicity in chicken. Recombinants containing the engineered H2, H4, H8, or H14 in the HPAIV background were lethal and exhibited i.v. pathogenicity indices of 2.79, 2.37, 2.85, and 2.61, respectively, equivalent to naturally occurring H5 or H7 HPAIV. Moreover, the H2, H4, and H8 reassortants were transmitted to some contact chickens. The H2 reassortant gained two mutations in the M2 proton channel gate region, which is affected in some HPAIVs of various origins. Taken together, in the presence of a polybasic HA cleavage site, non-H5/H7 HA can support a highly pathogenic phenotype in the appropriate viral background, indicating requirement for further adaptation. Therefore, the restriction of natural HPAIV to serotypes H5 and H7 is likely a result of their unique predisposition for acquisition of a polybasic HA cleavage site. 相似文献
95.
Xiaoping Liu Jana M. Mitchell Richard W. Wozniak G��nter Blobel Jie Fan 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(41):16498-16503
The coatomer module of the nuclear pore complex borders the cylinder-like nuclear pore-membrane domain of the nuclear envelope. In evolution, a single coatomer module increases in size from hetero-heptamer (Saccharomyces cerevisiae) to hetero-octamer (Schizosaccharomyces pombe) to hetero-nonamer (Metazoa). Notably, the heptamer–octamer transition proceeds through the acquisition of the nucleoporin Nup37. How Nup37 contacts the heptamer remained unknown. Using recombinant nucleoporins, we show that Sp-Nup37 specifically binds the Sp-Nup120 member of the hetero-heptamer but does not bind an Sc-Nup120 homolog. To elucidate the Nup37–Nup120 interaction at the atomic level, we carried out crystallographic analyses of Sp-Nup37 alone and in a complex with an N-terminal, ∼110-kDa fragment of Sp-Nup120 comprising residues 1–950. Corroborating structural predictions, we determined that Nup37 folds into a seven-bladed β-propeller. Several disordered surface regions of the Nup37 β-propeller assume structure when bound to Sp-Nup120. The N-terminal domain of Sp-Nup1201–950 also folds into a seven-bladed propeller with a markedly protruding 6D–7A insert and is followed by a contorted helical domain. Conspicuously, this 6D–7A insert contains an extension of 50 residues which also is highly conserved in Metazoa but is absent in Sc-Nup120. Strikingly, numerous contacts with the Nup37 β-propeller are located on this extension of the 6D–7A insert. Another contact region is situated toward the end of the helical region of Sp-Nup1201–950. Our findings provide information about the evolution and the assembly of the coatomer module of the nuclear pore complex. 相似文献
96.
Koller T Kollerova J Hlavaty T Huorka M Payer J 《Scandinavian journal of gastroenterology》2012,47(2):197-203
Cholelithiasis and nonalcoholic fatty liver disease (NAFLD) share the same risk factors. The aim of our study was to explore the relationship between these two conditions and to identify independent predictors of both diseases in a cohort of patients with metabolic risk factors. Consecutive patients with metabolic risk factors referred to the outpatient clinic during a one-year period were included. Cholelithiasis was defined by the presence of gallstones on abdominal ultrasound examination at inclusion or previously performed cholecystectomy. NAFLD was defined by the presence of at least one surrogate marker such as elevated alanine aminotransferase and/or gamma-glutamyl transpeptidase and/or ultrasound signs of fatty liver. Other common liver diseases were thoroughly excluded. The prevalence of cholelithiasis among patients with and without NAFLD was determined and clinical and laboratory parameters were identified as predictors of NAFLD by multivariate logistic regression. In total, 482 consecutive patients were included: mean age 61 years; 61% were women; 52% of patients had more than 2 metabolic risk factors (obesity, type 2 diabetes, hypertension, hypertriglyceridemia, or low HDL cholesterol). NAFLD and cholelithiasis were present in 41% and 34% of all patients, respectively. Significantly higher prevalence of cholelithiasis was found among patients with NAFLD compared with patients without NAFLD (47% vs. 26%, respectively; p < 0.0001). In multivariate logistic regression model, type 2 diabetes (odds ratio (OR) = 1.99), BMI above 25 kg/m(2) (OR = 1.78), and cholelithiasis (OR = 1.77) were identified as independent predictors of NAFLD. Fifty six percent of patients with cholelithiasis had NAFLD compared with 33% of patients without cholelithiasis (p < 0.0001). Multivariate logistic regression identified age above 50 years (OR = 3.46), NAFLD (OR = 1.92), triglycerides above 1.7 mmol/l (OR = 1.91), BMI above 25 kg/m(2) (OR = 1.84), and total cholesterol concentration (OR = 0.711) as independent predictors of cholelithiasis. In conclusion, patients with metabolic risk factors and cholelithiasis suffer significantly more often from NAFLD compared with the reference group. Cholelithiasis represents an independent risk factor of NAFLD in addition to metabolic risk factors and could be regarded as an additional risk factor of liver damage in patients with NAFLD. Furthermore, NAFLD is an independent risk factor for cholelithiasis and might represent a pathogenetic link between the metabolic syndrome and cholelithiasis. 相似文献
97.
98.
Abdollahpour H Appaswamy G Kotlarz D Diestelhorst J Beier R Schäffer AA Gertz EM Schambach A Kreipe HH Pfeifer D Engelhardt KR Rezaei N Grimbacher B Lohrmann S Sherkat R Klein C 《Blood》2012,119(15):3450-3457
We describe a novel clinical phenotype associating T- and B-cell lymphopenia, intermittent neutropenia, and atrial septal defects in 3 members of a consanguineous kindred. Their clinical histories included recurrent bacterial infections, viral infections, mucocutaneous candidiasis, cutaneous warts, and skin abscesses. Homozygosity mapping and candidate gene sequencing revealed a homozygous premature termination mutation in the gene STK4 (serine threonine kinase 4, formerly having the symbol MST1). STK4 is the human ortholog of Drosophila Hippo, the central constituent of a highly conserved pathway controlling cell growth and apoptosis. STK4-deficient lymphocytes and neutrophils exhibit enhanced loss of mitochondrial membrane potential and increased susceptibility to apoptosis. STK4 deficiency is a novel human primary immunodeficiency syndrome. 相似文献
99.
100.