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51.
52.
Temporary loss of perivascular aquaporin-4 in neocortex after transient middle cerebral artery occlusion in mice
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Frydenlund DS Bhardwaj A Otsuka T Mylonakou MN Yasumura T Davidson KG Zeynalov E Skare O Laake P Haug FM Rash JE Agre P Ottersen OP Amiry-Moghaddam M 《Proceedings of the National Academy of Sciences of the United States of America》2006,103(36):13532-13536
The aquaporin-4 (AQP4) pool in the perivascular astrocyte membranes has been shown to be critically involved in the formation and dissolution of brain edema. Cerebral edema is a major cause of morbidity and mortality in stroke. It is therefore essential to know whether the perivascular pool of AQP4 is up- or down-regulated after an ischemic insult, because such changes would determine the time course of edema formation. Here we demonstrate by quantitative immunogold cytochemistry that the ischemic striatum and neocortex show distinct patterns of AQP4 expression in the reperfusion phase after 90 min of middle cerebral artery occlusion. The striatal core displays a loss of perivascular AQP4 at 24 hr of reperfusion with no sign of subsequent recovery. The most affected part of the cortex also exhibits loss of perivascular AQP4. This loss is of magnitude similar to that of the striatal core, but it shows a partial recovery toward 72 hr of reperfusion. By freeze fracture we show that the loss of perivascular AQP4 is associated with the disappearance of the square lattices of particles that normally are distinct features of the perivascular astrocyte membrane. The cortical border zone differs from the central part of the ischemic lesion by showing no loss of perivascular AQP4 at 24 hr of reperfusion but rather a slight increase. These data indicate that the size of the AQP4 pool that controls the exchange of fluid between brain and blood during edema formation and dissolution is subject to large and region-specific changes in the reperfusion phase. 相似文献
53.
Effects of 8-OH-DPAT and fluoxetine on activity and attack by female mice towards lactating intruders 总被引:1,自引:0,他引:1
1. The impact of the serotoninergic receptor on the attack directed by female mice towards lactating intruders was assessed by studying the effects of 8-OH-DPAT (a serotoninergic agonist) and fluoxetine (an inhibitor of serotonin reuptake) on this paradigm at a range of doses and post-injection durations. 2. The specificity of these drug actions behaviour were examined by studying their effects on wheel running activity and performance in the open field. Non-sedative doses of 200 and 250 micrograms/kg of 8-OH-DPAT reduced attack by resident females on lactating intruders. 3. Higher doses (12-16 mg/kg) of fluoxetine reduced activity measures whereas lower non-sedative doses (up to 8 mg/kg) were without action on this aggression paradigm. 4. Additional studies with specific serotoninergic drugs are needed to clarify the role of this transmitter in attack by female mice on lactating intruders. 相似文献
54.
Michael P. Bender Jeffrey B. Aitman Simon J. Biggs Ursula Haug 《British Journal of Learning Disabilities》1983,11(4):168-169
SUMMARY: The authors describe a 69 item sexual knowledge questionnaire that covers the areas: physiology, pregnancy, the sex act, masturbation, contraception, types of sexuality, and venereal disease. There is also a ‘Belief in Myths’ scale. Mean scores for delinquent boys and young mentally handicapped adults are given, with the latter having lower scores. All areas correlate with total score. The handicapped group showed increased sexual knowledge when re-tested after a human relations course. A control group, tested after the same interval, showed only random changes. Further research is suggested. 相似文献
55.
56.
Markus Moessner Christine Gallas Severin Haug Hand Kordy 《Clinical psychology & psychotherapy》2011,18(4):331-338
Background: Monitoring psychotherapeutic progress requires valid and economic measures to detect change of clinical relevance. We addressed validity and sensitivity to change of the ‘Klinisch Psychologisches Diagnosesystem 38’ (KPD‐38, Clinical Psychological Diagnosis System), an instrument for outcome monitoring and quality assurance. Methods: Data from an inpatient sample (n = 1.377) were used to investigate the concurrent validity, the sensitivity to change, and the criterion validity of the KPD‐38 in comparison to the Outcome Questionnaire (OQ‐45) and the Brief Symptom Inventory (BSI). Results: Sensitivity‐specificity analyses showed similar sensitivity and higher specificity for the KPD‐38 scales compared with the BSI and OQ total scores. Change rates on the KPD‐38 distress scale (DIS) were found to be lower than on the BSI (KPD‐38 DIS: 36.6%, GSI: 67.7%) and the OQ‐45 (KPD‐38 DIS: 44.3%, OQ tot: 57.1%) total scores. Concordance was low with the BSI ([κ = 0.24] and moderate with the OQ‐45 [κ = 0.45]). Discussion: Implications for applications in the field of outcome assessment and the challenge of further validation are discussed. The relation between sensitivity to change and criterion validity is highlighted. Copyright © 2010 John Wiley & Sons, Ltd. Key Practitioner Messages: ? The KPD‐38 is a self‐report questionnaire for outcome monitoring and quality assurance, which is free of charge for research purposes. ? Both OQ‐45 and BSI show higher sensitivity to change than the KPD‐38, overall concordance of change is moderate. ? Aspects of validity should be considered in the evaluation of sensitivity to change. 相似文献
57.
How to use the world's scarce selenium resources efficiently to increase the selenium concentration in food 总被引:1,自引:0,他引:1
Haug A Graham RD Christophersen OA Lyons GH 《Microbial Ecology in Health and Disease》2007,19(4):209-228
The world's rare selenium resources need to be managed carefully. Selenium is extracted as a by-product of copper mining and there are no deposits that can be mined for selenium alone. Selenium has unique properties as a semi-conductor, making it of special value to industry, but it is also an essential nutrient for humans and animals and may promote plant growth and quality. Selenium deficiency is regarded as a major health problem for 0.5 to 1 billion people worldwide, while an even larger number may consume less selenium than required for optimal protection against cancer, cardiovascular diseases and severe infectious diseases including HIV disease. Efficient recycling of selenium is difficult. Selenium is added in some commercial fertilizers, but only a small proportion is taken up by plants and much of the remainder is lost for future utilization. Large biofortification programmes with selenium added to commercial fertilizers may therefore be a fortification method that is too wasteful to be applied to large areas of our planet. Direct addition of selenium compounds to food (process fortification) can be undertaken by the food industry. If selenomethionine is added directly to food, however, oxidation due to heat processing needs to be avoided. New ways to biofortify food products are needed, and it is generally observed that there is less wastage if selenium is added late in the production chain rather than early. On these bases we have proposed adding selenium-enriched, sprouted cereal grain during food processing as an efficient way to introduce this nutrient into deficient diets. Selenium is a non-renewable resource. There is now an enormous wastage of selenium associated with large-scale mining and industrial processing. We recommend that this must be changed and that much of the selenium that is extracted should be stockpiled for use as a nutrient by future generations. 相似文献
58.
Arterial damage, causing ischemia of the limb, occurs in less than 5 per cent of all instances of thoracic outlet syndrome. Arterial complications are usually associated with cervical ribs or rudimentary first ribs, but 12 per cent have occurred in patients with no osseous abnormality. The physiopathologic factors begin with compression of the subclavian artery which, in most patients, produces stenosis, poststenotic dilatation, formation of aneurysms and mural thrombosis. In other patients, aneurysms do not form, but the compression still causes stenosis, intimal injury and mural thrombosis. With either scenario, distal embolization can occur and produce signs and symptoms of ischemia that can limb-threatening. In this study, more than 200 patients reported previously and five additional sides in four patients were reviewed. Treatment depends upon the condition of the patient at presentation. Those with osseous abnormalities and no aneurysm or symptoms are not treated, while those with poststenotic dilatation or small aneurysms undergo rib resection only. Aneurysms more than twice the arterial diameter, intimal injury or mural thrombus are indications to resect, replace or bypass the subclavian artery. Patients who have had distal embolization and severe ischemic symptoms require, in addition to the aforementioned, distal thromboembolectomy, dorsal sympathectomy or both. Good results from treatment have been reported in 84 per cent of the 137 patients reported since 1970; 3 per cent required amputation and 3 per cent had cerebral emboli. Because the severe arterial complications were primarily the result of delayed therapy, they can best be avoided by early recognition, diagnosis and treatment. 相似文献
59.
Effects of dietary long-chain polyunsaturated fatty acids on the essential fatty acid status of premature infants 总被引:12,自引:0,他引:12
B. Koletzko E. Schmidt H. J. Bremer M. Haug G. Harzer 《European journal of pediatrics》1989,148(7):669-675
The effect of different diets on the percentage content of long-chain polyunsaturated fatty acids (LCP; metabolites of linoleic and alpha-linolenic acids) in plasma lipids was studied in 29 premature infants on days 4 and 21 of life. Eleven infants were fed human milk which supplies LCP (1.7% of the fatty acids), 10 a commercially available milk formula without LCP, and 8 a new formula enriched with LCP of the omega-6 and the omega-3 series (0.5% LCP). LCP values in plasma lipids remained stable during the observation period in infants fed human milk. In contrast, LCP decreased markedly in plasma lipids of infants fed the conventional formula. Since the precursor fatty acids linoleic and alpha-linolenic acids were high in their diet and plasma, this finding indicates that premature infants have a limited capacity for LCP biosynthesis and may require their dietary supplementation. Infants fed the LCP enriched formula had significantly higher LCP proportions in plasma lipids than infants given the conventional formula, but less than infants fed human milk. Our results demonstrate that small concentrations of dietary LCP have marked effects on plasma lipid composition, particularly on phospholipids, suggesting that dietary LCP are preferentially channelled into structural lipids. We conclude that the essential fatty acid status of formula-fed premature infants can be improved by a supplementation of omega-6- and omega-3-LCP.Abbreviation LCP
long-chain polyunsaturated fatty acids 相似文献
60.
Vitamin K1 content of maternal milk: influence of the stage of lactation, lipid composition, and vitamin K1 supplements given to the mother 总被引:3,自引:0,他引:3
Using a sensitive electrochemical assay for vitamin K1 and standardized techniques for breast-milk collection, we studied the vitamin K1 content of human milk during the first 5 wk of lactation with respect to 1) individual and interindividual differences, 2) the relationship of vitamin K1 to other lipids, and 3) the influence of oral supplements of vitamin K1 on breast milk concentrations. Comparison of fore and hind milk from the mothers revealed higher vitamin K1 concentrations in hindmilks, suggesting that the lipid content influences the vitamin K1 concentration in maternal milk. Samples of maternal milk from nine mothers collected from day 1 to day 36 of lactation showed significantly higher vitamin K1 concentrations in colostral milk than in mature milk. For colostral milk there was a significant correlation of vitamin K1 to cholesterol (r = 0.62) but not to total lipid or phospholipid suggesting a role for cholesterol in the secretion of vitamin K1 into colostral milk. For mature milk correlation coefficients of vitamin K1 with all lipids were low (r = 0.29-0.37) suggesting that at later stages of lactation dietary fluctuations of vitamin K1 may be a more important determinant of the vitamin K1 content of breast milk than the lipid composition. To test the influence of diet, mothers were given oral supplements of vitamin K1.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献