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131.
Closing the loop: a spatial analysis to link observed environmental damage to predicted heavy metal emissions 总被引:3,自引:0,他引:3
Colgan A Hankard PK Spurgeon DJ Svendsen C Wadsworth RA Weeks JM 《Environmental toxicology and chemistry / SETAC》2003,22(5):970-976
In many cases, the link between industrial emissions and damage to the environment can only be inferred. The Environment Agency of the United Kingdom imposes emissions limits on industrial sites so that predicted concentrations and deposition rates remain below standard thresholds. Estimates of appropriate critical levels and loads are usually based on laboratory results and rarely estimate synergistic effects between pollutants or consider biological adaptation or selection in the target receptor organisms. The Avonmouth smelter has been emitting zinc and other heavy metals since 1929. It has been the subject of a number of detailed and synoptic studies, especially the impact on soil invertebrates. Damage was assessed using both physiological and ecological measurements. Two methods of spatial analysis were investigated, namely interpolation using standard geographical information system (GIS) operators and atmospheric dispersal modeling using an off-the-shelf model. Both methods can be used to compute contours (isolines) of predicted biological effect. Correlation results show that dispersal modeling is at least as good as kriging but requires much less data. This article demonstrates the usefulness of GIS and dispersal models as tools in decision making to determine the most suitable sampling sites in the assessment and monitoring of the impact of contamination around major point sources. 相似文献
132.
Summary.
The objective was to identify risk factors for shunt infections, and establish the rate of infection for shunt procedures
carried out under standardized conditions in a well-defined population. All (407) paediatric shunt operations (primary and
revisions) performed within a total population of 630000 inhabitants between January 1, 1986 and December 31, 1996, were analysed
retrospectively. 11 shunt infections were diagnosed in 10 patients, giving an overall infection rate of 2.7% per procedure
and 6.2% per patient. Infections were significantly correlated with age, type of operation, and a etiology of hydrocephalus.
Thus, infections occurred more frequently during the first 6 months of life, more often following primary shunt insertions
compared with revisions, and children with myelomeningocele had a higher infection risk than children with hydrocephalus due
to other causes. There was a highly significant male preponderance in the patient material.
Conclusion: The overall infection rate was relatively low. The risk factors for shunt infections appear to relate to epidemiological
characteristics rather than to surgical factors.
Published online April 28, 2003
Correspondence: Professor Knut Wester, Department of Neurosurgery, Haukeland University Hospital, N 5021 Bergen, Norway. 相似文献
133.
Strøm MB Haug BE Skar ML Stensen W Stiberg T Svendsen JS 《Journal of medicinal chemistry》2003,46(9):1567-1570
Cationic antibacterial peptides have been proclaimed as new drugs against multiresistant bacteria. Their limited success so far is partially due to the size of the peptides, which gives rise to unresolved issues regarding administration, bioavailability, metabolic stability, and immunogenicity. We have systematically investigated the minimum antibacterial motif of cationic antibacterial peptides regarding charge and lipophilicity/bulk and found that the pharmacophore was surprisingly small, opening the opportunity for development of short antibacterial peptides for systemic use. 相似文献
134.
This study evaluated the accuracy of the interpretation of the chest film in delineating localised abnormalities of ventilation and perfusion, as well as the overall severity of airways obstruction, exercise tolerance, and clinical condition in children with cystic fibrosis. Radiographic findings in various regions of the chest film were compared with the functional values obtained with regional lung function tests which evaluated the arrival and disappearance of boluses of radioactive nitrogen given by inhalation and infusion. While the more severely affected areas on the chest radiograph were found to correlate with similar regions on the lung function tests, as did overall scores, errors occurred in some cases if the x-ray film alone was used as a judge of regional physiological derangement. In addition the degree of airways obstruction, the exercise tolerance on a cycle ergometer, and clinical grading, each correlated significantly with the radiographic score. We conclude that the chest radiograph is a good indicator of the overall severity of the lung disease and that it correlates well with exercise tolerance and clinical condition in cystic fibrosis. 相似文献
135.
Svendsen KB Bech JN Sørensen TB Pedersen EB 《European journal of clinical pharmacology》2000,56(5):383-388
Background: Non-steroidal anti-inflammatory drugs (NSAIDs) are known to be potentially nephrotoxic agents. NSAIDs inhibit the enzyme
cyclo-oxygenase and thereby block the prostagladin synthesis in the kidneys. Cyclo-oxygenase exists in two isoforms (COX-1
and COX-2). It has been proposed that NSAIDs with preferential COX-2 selectivity have fewer renal side effects than drugs
with preferential COX-1 selectivity. Etodolac is a relative selective inhibitor of COX-2, while ibuprofen has a higher potency
against COX-1 than COX-2.
Objective: In this study, we compared the effects of etodolac and ibuprofen on renal function, plasma renin, plasma arginine vasopressin
and the urinary excretion of albumin and α-glutathione-S-transferase (α-GST).
Methods: In a randomised, double-blind, three-way crossover study with placebo, we compared the effects of 2 weeks of treatment with
ibuprofen and etodolac on renal haemodynamics [glomerular filtration rate (GFR), renal plasma flow (RPF) and filtration fraction
(FF)], tubular function and plasma concentrations of the hormones renin (PRC) and arginine vasopressin (AVP) in 18 healthy
subjects. In addition, we examined the effects on the urinary excretion of albumin and α-GST as markers of renal injury.
Results: No differences were found between the three treatments, placebo, ibuprofen and etodolac, in the effects on GFR, RPF, FF,
free water clearance, urinary output or fractional excretion of potassium and sodium. However, ibuprofen, in contrast to etodolac,
caused a significant decrease in both lithium clearance (−16% versus placebo) and the fractional excretion of lithium (−17%
versus placebo), suggesting an increase in the re-absorption in the proximal tubuli. PRC was reduced significantly by ibuprofen
(−32% versus placebo) but not etodolac. None of the drugs changed AVP. Fourteen days of treatment with ibuprofen caused a
significant decrease (−47% versus placebo) in the urinary excretion of α-GST, while no changes were seen after etodolac. None
of the drugs changed the urinary excretion of albumin.
Conclusion: In conclusion, a 14-day administration of etodolac or ibuprofen in therapeutic doses did not affect the renal haemodynamics,
the net excretion of electrolytes or the urinary excretion of albumin in healthy subjects. However, ibuprofen, in contrast
to etodolac, caused a reduction in PRC, suggesting that COX-1 is involved in basal renin release in humans. Furthermore, ibuprofen
decreased lithium excretion suggesting that COX-1 is involved in the re-absorption of sodium and/or water in the proximal
tubuli. The reduction in the urinary excretion of α-GST by ibuprofen may be caused by an inhibition of the detoxification
enzyme by ibuprofen. Overall the study indicates that only small differences in the effects of the two drugs on renal function
in healthy subjects exist during a treatment period of 2 weeks.
Received: 10 November 1999 / Accepted: 21 April 2000 相似文献
136.
Scintiscans of liver and spleen using technetium 99m sulphur colloid in 15 infants with extrahepatic biliary atresia and 11 infants with severe obstructive jaundice (7 with genetic deficiency of alpha 1-antitrypsin) showed similar hepatic size, pattern of isotope uptake, and splenic abnormality with no distinguishing features. In 37 older children with a variety of liver disorders, the scan was invaluable in showing filling defects in five instances. Selenomethionine was taken up not only by the two filling defects due to hepatoblastoma but also in a haemangioendothelioma. In the remaining patiens liver scanning confirmed hepatic abnormality and the necessity for more specific invasive diagnostic investigations. 相似文献
137.
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140.
Fahmi A. AL-Kaf Turki A. AL Garni Nahes AL-Harbi Hassan Sandokji Sondos Samargandy 《Journal of the Saudi Heart Association》2021,33(1):71
A 21-years-old with Down syndrome presented with respiratory distress. Initial investigations revealed a cardiac tamponade. On further evaluation, he had positive coronavirus disease-2019 (COVID-19), severe chest infection and severe hypothyroidism. He responded well to urgent pericardiocentesis, levothyroxine, hydrocortisone and tocilizumab. 相似文献