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961.
Patrícia Machado Rui Pereira Ana Mafalda Rocha Licínio Manco Natércia Fernandes Juliana Miranda Letícia Ribeiro Virgílio E. Do Rosário António Amorim Leonor Gusmão Ana Paula Arez 《British journal of haematology》2010,149(5):775-784
The genetic component of susceptibility to malaria is both complex and multigenic and the better‐known protective polymorphisms are those involving erythrocyte‐specific structural proteins and enzymes. In vivo and in vitro data have suggested that pyruvate kinase deficiency, which causes a nonspherocytic haemolytic anaemia, could be protective against malaria severity in humans, but this hypothesis remains to be tested. In the present study, we conducted a combined analysis of Short Tandem Repeats (STRs) and Single Nucleotide Polymorphisms (SNPs) in the pyruvate kinase‐encoding gene (PKLR) and adjacent regions (chromosome 1q21) to look for malaria selective signatures in two sub‐Saharan African populations from Angola and Mozambique, in several groups with different malaria infection outcome. A European population from Portugal, including a control and a pyruvate kinase‐deficient group, was used for comparison. Data from STR and SNP loci spread along the PKLR gene region showed a considerably higher differentiation between African and Portuguese populations than that usually found for neutral markers. In addition, a wider region showing strong linkage disequilibrium was found in an uncomplicated malaria group, and a haplotype was found to be associated with this clinical group. Altogether, this data suggests that malaria selective pressure is acting in this genomic region. 相似文献
962.
Hanna Eneroth Lars‐Åke Persson Shams El Arifeen Eva‐Charlotte Ekström 《Acta paediatrica (Oslo, Norway : 1992)》2011,100(2):220-225
Aim: To estimate the prevalence of infant anaemia and its association with iron deficiency, growth, infection and other micronutrient deficiencies. Methods: Using data from MINIMat, a randomized maternal food and micronutrient supplementation trial, we assessed the associations between anaemia (haemoglobin < 105 g/L) in 580 infants at 6 months and deficiencies of iron, vitamin A, vitamin B12, zinc and folate, infection and anthropometric indices. Variables associated with anaemia in bivariate analyses were evaluated in logistic regression models, adjusting for potential confounders. Results: Anaemia was found in 46% of the infants, and among these, 28% had iron deficiency (plasma ferritin <9 μg/L). Elevated C‐reactive protein (>10mg/L) (OR = 2.7, 95% CI: 1.6, 4.7), low birthweight (OR = 2.3, 95% CI: 1.5, 3.5) and iron deficiency (OR = 2.2, 95% CI: 1.4, 3.6) were independently associated with increased risk for anaemia. We also observed a seasonal variation in anaemia not mediated through the other factors studied. Conclusion: In a cohort in rural Bangladesh, anaemia at age 6 months was common and associated with infection, low birthweight and iron deficiency. 相似文献
963.
Antony Parker Juan Irure Ventura Dawn Sims Ainara Echeverría de Carlos Ricardo Gómez de la Torre Lourdes Tricas Aizpún 《Journal of immunoassay & immunochemistry》2017,38(5):514-522
IgG2 is the most efficient subclass for providing protection against pneumococcal pathogens. We hypothesised that some individuals may be unable to mount an effective pneumococcal capsular polysaccharide (PCP) IgG2 response despite having a normal PCP IgG concentration (PCP IgG2 deficient). The median pre-vaccination PCP IgG2 concentration was significantly lower in individuals referred for immunological investigation compared to healthy controls (2.8 mg/L range, 95% CI 1.1–88 vs. 29.5mg/L, 95% CI 13.5–90, p = 0.0002). PCP IgG:IgG2 ratios were significantly higher for the referral population than for healthy controls suggesting the increased production of PCP specific subclasses other than IgG2. The percentage of individuals with PCP IgG2 deficiency was significantly higher in referral groups compared to controls (31% vs. 5%; p = 0.0009) and in an individual with PCP IgG2 deficiency, the balance of PCP specific IgG subclass antibodies post vaccination changed from IgG2>IgG1>IgG3>IgG4 to IgG1>IgG3>IgG2>IgG4. The median PCP IgG2 concentration in those with PCP IgG2 deficiency was significantly lower in the referral groups compared to controls (7.8 mg/L, 95% CI 1.1–12 vs. 12.7 mg/L, 95% CI 11.8–13.1; p = 0.006). The data suggests a defect in the production PCP IgG2 may be present in individuals with normal PCP IgG referred for immunological investigation. 相似文献
964.
965.
966.
《Hematology/oncology and stem cell therapy》2017,10(1):29-32
Splenic rupture in neonates is a rare event, usually occurring in the setting of underlying predisposing conditions. Here, we present the case of a term neonate who presented with worsening anemia in the setting of known hemolytic disease during the newborn period and was later found to have a spontaneous splenic rupture. He was subsequently diagnosed with severe hemophilia A, and was managed medically with recombinant factor VIII replacement therapy without any surgical intervention. This is the first reported case of a neonate who had spontaneous splenic rupture and severe hemophilia A, and underwent successful medical treatment without any surgical intervention. 相似文献
967.
Structural insights on pathogenic effects of novel mutations causing pyruvate carboxylase deficiency
Sophie Monnot Valérie Serre Bernadette Chadefaux‐Vekemans Joelle Aupetit Stéphane Romano Pascale De Lonlay Jean‐Marie Rival Arnold Munnich Julie Steffann Jean‐Paul Bonnefont 《Human mutation》2009,30(5):734-740
Pyruvate carboxylase (PC), a key enzyme for gluconeogenesis and anaplerotic pathways, consists of four domains, namely, biotin carboxylase (BC), carboxyltransferase (CT), pyruvate carboxylase tetramerization (PT), and biotin carboxyl carrier protein (BCCP). PC deficiency is a rare metabolic disorder inherited in an autosomal recessive way. The most severe form (form B) is characterized by neonatal lethal lactic acidosis, whereas patients with form A suffer chronic lactic acidosis with psychomotor retardation. Diagnosis of PC deficiency relies on enzymatic assay and identification of the PC gene mutations. To date, six mutations of the PC gene have been identified. We report nine novel mutations of the PC gene, in five unrelated patients: three being affected with form B, and the others with form A. Three of them were frameshift mutations predicted to introduce a premature termination codon, the remaining ones being five nucleotide substitutions and one in frame deletion. Impact of these mutations on mRNA was assessed by RT‐PCR. Evidence for a deleterious effect of the missense mutations was achieved using protein alignments and three‐dimensional structural prediction, thanks to our modeling of the human PC structure. Altogether, our data and those previously reported indicate that form B is consistently associated with at least one truncating mutation, mostly lying in CT (C‐terminal part) or BCCP domains, whereas form A always results from association of two missense mutations located in BC or CT (N‐terminal part) domains. Finally, although most PC mutations are suggested to interfere with biotin metabolism, none of the PC‐deficient patients was biotin‐responsive. Hum Mutat 0:1–7, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
968.
969.
Muge Gokce Murat Tuncer Mualla Cetin Fatma Gumruk 《Indian journal of hematology & blood transfusion》2013,29(3):161-163
A three-month-old boy presented with growth failure, skeletal abnormalities, otitis media and pancytopenia. Exocrine pancreatic insufficiency was confirmed by low levels of fecal elastase. He was diagnosed as Shwachman-Diamond syndrome by clinical and laboratory findings. The diagnosis was confirmed by sequence analysis for SBDS gene on chromosome seven revealing compound heterozygous mutation, which are c.258+2T-C and c.183-184TA-CT. Matched unrelated donor screening for hematopoietic stem cell transplantation was initiated. Unfortunately, he died of respiratory difficulty at 5 months of age. Our case is the youngest patient whose presumptive Shwachman-Diamond syndrome diagnosis was confirmed by molecular analysis. 相似文献
970.
Winyoo Chowanadisai David M. Graham Carl L. Keen Robert B. Rucker Mark A. Messerli 《Proceedings of the National Academy of Sciences of the United States of America》2013,110(24):9903-9908
Zn2+ is required for many aspects of neuronal structure and function. However, the regulation of Zn2+ in the nervous system remains poorly understood. Systematic analysis of tissue-profiling microarray data showed that the zinc transporter ZIP12 (slc39a12) is highly expressed in the human brain. In the work reported here, we confirmed that ZIP12 is a Zn2+ uptake transporter with a conserved pattern of high expression in the mouse and Xenopus nervous system. Mouse neurons and Neuro-2a cells produce fewer and shorter neurites after ZIP12 knockdown without affecting cell viability. Zn2+ chelation or loading in cells to alter Zn2+ availability respectively mimicked or reduced the effects of ZIP12 knockdown on neurite outgrowth. ZIP12 knockdown reduces cAMP response element-binding protein activation and phosphorylation at serine 133, which is a critical pathway for neuronal differentiation. Constitutive cAMP response element-binding protein activation restores impairments in neurite outgrowth caused by Zn2+ chelation or ZIP12 knockdown. ZIP12 knockdown also reduces tubulin polymerization and increases sensitivity to nocodazole following neurite outgrowth. We find that ZIP12 is expressed during neurulation and early nervous system development in Xenopus tropicalis, where ZIP12 antisense morpholino knockdown impairs neural tube closure and arrests development during neurulation with concomitant reduction in tubulin polymerization in the neural plate. This study identifies a Zn2+ transporter that is specifically required for nervous system development and provides tangible links between Zn2+, neurulation, and neuronal differentiation. 相似文献