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991.
Serological and phylogenetic evidence of monotypic immune responses to different mumps virus strains
The recent resurgence of mumps epidemics in many countries with ongoing vaccination programs along with evidence of antigenic diversity among mumps virus strains have recently challenged the assumption that mumps virus is serologically monotypic. To address this controversy, we sought to identify two mumps virus strains that would best represent different serotypes, should multiple serotypes exist, and assess the ability of human sera to neutralize both strains. The virus strains, Enders and Lo1, were selected based upon a phylogenetic analysis of the major target of neutralizing antibody, the viral hemagglutinin-neuraminidase (HN) protein, along with data reported by others indicating that (1) these viruses are antigenically distinct and (2) genotypically similar strains have been implicated in cases of reinfection. Our results show that of sera capable of neutralizing one of the virus strains, 90% could neutralize the other, although significant differences in neutralization titers were noted. Though the latter confirms the existence of inter-strain antigenic variability, the fact that few sera were unable to neutralize both virus strains argues against the presence of multiple serotypes. Of those sera incapable of co-neutralization, all but one had low neutralization titers (1:8), suggesting that individuals possessing low levels of neutralizing antibody may be at risk for breakthrough infections, thereby providing an explanation for cases of infection in previously infected or vaccinated individuals. 相似文献
992.
Evaluating the contribution of soil properties to modifying lead phytoavailability and phytotoxicity 总被引:2,自引:0,他引:2
Dayton EA Basta NT Payton ME Bradham KD Schroder JL Lanno RP 《Environmental toxicology and chemistry / SETAC》2006,25(3):719-725
Soil properties affect Pb bioavailability to human and ecological receptors and should be considered during ecological risk assessment of contaminated soil. We used path analysis (PA) to determine the relative contribution of soil properties (pH, organic C [OC], amorphous Fe and Al oxides [FEAL], and cation-exchange capacity [CEC]) in modifying Pb bioavailability. The response of biological endpoints (bioaccumulation and dry matter growth [DMG]) of lettuce (Lactuca sativa) grown on 21 Pb-spiked (2,000 mg/kg) soils were determined. Lettuce tissue Pb ranged from 3.22 to 233 mg/kg, and relative DMG ranged from 2.5 to 88.5% of their respective controls. Simple correlation showed strong relationships between CEC and OC (p < 0.01) and weaker relationships between pH and FEAL (p < 0.05) and Pb bioaccumulation. Results of PA suggest that soil pH increased the negative surface charge of organic matter and clay, thereby increasing CEC and decreasing Pb bioaccumulation. Also, the direct effect of OC on tissue Pb can be attributed to formation of surface Pb complexes by organic matter functional group ligands. Increased OC and/or CEC reduced Pb solubility and bioavailability in the 21 soils in the present study. The relative importance of soil properties likely will vary between studies employing different soils. Soil properties should be considered during the ecological risk assessment of metal in contaminated soils. Path analysis is useful for ecological studies involving soils with a wide range of physicochemical properties and can assist in site risk assessment of metals and remediation decisions on contaminated sites. 相似文献
993.
Pritchard C Duffy S Edington J Pang F 《JPEN. Journal of parenteral and enteral nutrition》2006,30(1):52-59
BACKGROUND: We sought to review the economics literature on enteral nutrition (EN) and oral nutrition supplements (ONS) against the background of an ongoing clinical guideline development. METHODS: We searched the Health Economic Evaluations Database, the NHS Economic Evaluation Database, and the Cochrane Database of Systematic Reviews. RESULTS: Enteral vs parenteral nutrition was found to be the most common comparison undertaken. The randomized trial evidence suggests that, in some groups of patients, EN is better in terms of clinical endpoints and/or length of hospital stay. This should translate into a lower mean cost for EN, given the reduced daily cost. These studies should be treated with caution because of their small sample size and poor quality. Costing was often crude and poorly reported, tending to focus on the narrow costs of the nutrition supplements. Only 1 study of a nutrition supplement in the community setting was found. CONCLUSIONS: There is some evidence to indicate economic advantages of enteral over parenteral nutrition and of immune-enhancing supplements relative to control diet. There is a lack of well-designed studies taking a broad view of relevant comparators, costs, and outcomes. The cost-effectiveness of different forms of nutrition in different patient groups remains to be established. 相似文献
994.
Bermingham EN McNabb WC Sutherland IA Sinclair BR Treloar BP Roy NC 《The British journal of nutrition》2006,96(1):28-38
Poor growth during parasitic infection may be due to a redistribution of amino acids away from skeletal muscle protein synthesis to the intestinal site of infection. The effect of a Trichostrongylus colubriformis infection on whole-body amino acid kinetics and tissue fractional protein synthesis rates were determined in lambs fed fresh Sulla (Hedysarum coronarium; 800 g DM/d). Lambs were dosed with 6000 L3 Trichostrongylus colubriformis larvae daily for 6 d (n 6) or kept as parasite-free controls (n 6). On day 45 post-infection, the lambs received an intravenous injection of 2H2O and infusions (8 h) of [35S]sulphate to measure the size of the whole-body water and sulphate pools, respectively. On day 48, the lambs were continuously infused for 8 h with [3,4-3H]valine into the jugular vein as well as with [1-13C]valine and [35S]cysteine into the abomasum. After the 8 h infusions, the lambs were killed and tissue samples collected from the duodenum, ileum, mesenteric lymph nodes, liver, spleen, thymus, muscle and skin. Feed intake (769 v. 689 (sd 47) g DM/d) was not affected by infection, whereas liveweight gains (50 v. -50 (sd 70) g/d) were lower and intestinal worm burdens (240 v. 18,000 (sd 7000) worms) higher in the infected lambs. Parasitic infection increased the fractional protein synthesis rates in the small intestine, mesenteric lymph nodes and liver but did not affect skin and skeletal muscle fractional protein synthesis rates during the established parasitic infection. 相似文献
995.
Blaine Easley R Sanders D McElrath-Schwartz J Martin J Mark Redmond J 《Paediatric anaesthesia》2006,16(1):66-71
Jacobsen syndrome (JS), also known as 11q-syndrome, is a congenital disorder associated with a deletion of the long arm of chromosome 11. Patients with JS characteristically exhibit multiple dysmorphic features, developmental delay, cardiac anomalies, and platelet abnormalities. Anesthetic issues related to the care of patients with JS concern airway management secondary to short neck, abnormal mouth shape and micrognathia/retrognathia, a high incidence of cardiac anomalies, and platelet dysfunction. Importantly, platelet abnormalities affect 95% of reported JS patients and involve platelet number, size and function. Two children with JS who required open heart surgery are presented and anesthetic management issues discussed. These patients represent the first reports regarding the perioperative issues in caring for patients with JS. 相似文献
996.
Clouse WD Rasmussen TE Perlstein J Sutherland MJ Peck MA Eliason JL Jazerevic S Jenkins DH 《Annals of vascular surgery》2006,20(4):429-434
Past wartime experience and recent civilian reports indicate upper extremity (UE) vascular injury occurs less often and with less limb loss than lower extremity (LE) injury. Given advances in critical care, damage control techniques, and military armor technology, the objective of this evaluation was to define contemporary patterns of UE injury and effectiveness of vascular surgical management in UE vascular injury during Operation Iraqi Freedom (OIF). From 1 September 2004 through 31 August 2005, 2,473 combat-related injuries were treated at the central echelon III surgical facility in Iraq. Patients with UE vascular injuries upon arrival were reviewed. Vessels injured were delineated. Therapeutic interventions, early limb viability, and complication rates following vascular repair were recorded. Of casualties treated during the study period, 43 (1.7%) UE and 83 (3.3%) LE vascular injuries were identified. Of the UE injuries, 11 (26%) had been operated on at forward locations and six (14%) had temporary shunts in place upon arrival at our facility. Injury levels included 10 (23%) subclavian-axillary, 25 (58%) brachial, and 10 (23%) distal to the brachial bifurcation. Two patients had multilevel injury. Twenty-eight grafts were placed, and 10 vessel repairs and eight ligations were performed. Two (4.7%) brachial interposition grafts required removal due to infection. Four (9.3%) subacute brachial graft thromboses occurred. Four (9.3%) patients underwent early UE amputation. In this most recent U.S. military evaluation of wartime UE vascular injury, UE injury appears rare, with LE injury twice as frequent. Yet, UE limb loss appears more substantial than noted previously. These findings are likely related to significant tissue destruction occurring with the combined mechanisms of injury sustained in OIF.Presented at the Sixteenth Annual Winter Meeting of the Peripheral Vascular Surgery Society, Park City, UT, January 27-29, 2006.The views expressed in this report are those of the authors and do not reflect the official policy of the Department of Defense or other departments of the U.S. government. 相似文献
997.
Paraskevas S Kandaswamy R Humar A Gillingham KJ Gruessner RW Payne WD Najarian JS Sutherland DE Matas AJ 《Clinical transplantation》2006,20(6):667-672
BACKGROUND: Determining factors associated with negative slope of inverse creatinine vs. time (1/Cr vs. t) may help prevent a decline in renal allograft function. METHODS: A total of 1389 adult recipients of primary renal transplants were divided into quartiles based on the slope of 1/Cr vs. t calculated from 6 and 12 months post transplant. A multivariate analysis of risk factors for being in the worst vs. best quartile employed these variables: donor source, HLA mismatch, recipient age, donor age, panel-reactive antibody (PRA), acute rejection (AR), 3-month cyclosporin A (CsA) level, 1-yr CsA level and acute tubular necrosis. Two separate analyses compared risk factors in patients with 1 and 3 yr survival, respectively. RESULTS: In recipients with > or = 1 yr graft survival, high PRA and AR were associated with negative slopes of 1/Cr vs. t. For those with > or = 3 yr graft survival, both AR and 3-month CsA level > 150 ng/mL were significant risk factors, using both 6- and 12-month slopes. Stratification of AR showed 1 AR episode > or = 6 months and multiple AR episodes carried significant risk for negative slopes. CONCLUSION: Optimization of allograft function invokes a conundrum between the needs to avoid both AR and high early CsA levels. We support a policy of carefully balancing these two risks. 相似文献
998.
999.
1000.
Meta-analysis of pancreaticojejunostomy versus pancreaticogastrostomy reconstruction after pancreaticoduodenectomy 总被引:7,自引:0,他引:7
McKay A Mackenzie S Sutherland FR Bathe OF Doig C Dort J Vollmer CM Dixon E 《The British journal of surgery》2006,93(8):929-936
BACKGROUND: Pancreaticoduodenectomy is the primary treatment for periampullary cancer. Associated morbidity is high and often related to pancreatic anastomotic failure. This paper compares rates of pancreatic fistula, morbidity and mortality after pancreaticoduodenectomy in patients having reconstruction by pancreaticogastrostomy with those in patients having reconstruction by pancreaticojejunostomy. METHODS: A meta-analysis was performed of all large cohort and randomized controlled trials carried out since 1990. RESULTS: Eleven articles were identified for inclusion: one prospective randomized trial, two non-randomized prospective trials and eight observational cohort studies. The meta-analysis revealed a higher rate of pancreatic fistula associated with pancreaticojejunostomy reconstruction (relative risk (RR) 2.62 (95 per cent confidence interval (c.i.) 1.91 to 3.60)). A higher overall morbidity rate was also demonstrated in this group (RR 1.43 (95 per cent c.i. 1.26 to 1.61)), as was a higher mortality rate (RR 2.51 (95 per cent c.i. 1.61 to 3.91)). CONCLUSION: Current literature suggests that the safer means of pancreatic reconstruction after pancreaticoduodenectomy is pancreaticogastrostomy, but much of the evidence comes from observational cohort study data. 相似文献