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101.
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Chronic fatigue syndrome (CFS) is characterized by fatigue lasting 6 months or longer. CFS has been associated with a disturbed (re-)activity of the autonomic nervous system. However, the sympathetic adrenomedulla (SAM) remains under-examined in CFS. To investigate SAM reactivity, we implemented a submaximal cycle ergometry (ERGO) and a pharmacological test (Insulin Tolerance Test, ITT) in 21 CFS patients and 20 age-, sex-, and BMI-matched controls. Plasma norepinephrine and epinephrine were collected once before and twice after the tests (+10/+20, and +30 min). Lower baseline levels and attenuated responses of epinephrine to the ERGO were found in CFS patients compared to controls, while the groups did not differ in their responses to the ITT. To conclude, we found evidence of altered sympathetic-neural and SAM reactivity in CFS. Exercise stress revealed a subtle catecholaminergic hyporeactivity in CFS patients. It is conceivable that inadequate catecholaminergic responses to physical exertion might contribute to CFS symptoms. 相似文献
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Pearl La Marca-Ghaemmaghami Roberto La Marca Sara M. Dainese Marina Haller Roland Zimmermann Ulrike Ehlert 《Journal of psychosomatic research》2013
Objective
Little is known about the effect of social support on the reactivity of the hypothalamic–pituitary–adrenal (HPA) axis during pregnancy. Moreover, when investigating the HPA axis most studies do not consider the activity of 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2), an enzyme within the salivary glands that inactivates cortisol to cortisone. This study explores the association between perceived emotional support and the maternal psychobiological stress response to a standardized naturalistic stressor by assessing maternal mood and the reactivity of salivary cortisol (SalF), salivary cortisone (SalE), and the SalE/(E + F) ratio as a marker of 11β-HSD2 activity.Methods
Repeated saliva samples and measures of maternal mood were obtained from 34 healthy second trimester pregnant women undergoing amniocentesis which served as a psychological stressor. The pregnant women additionally responded to a questionnaire of perceived emotional support and provided sociodemographic (e.g., maternal educational degree) and pregnancy-specific data (e.g., planned versus unplanned pregnancy).Results
Perceived emotional support neither showed a significant effect on mood nor on the SalF or SalE response to stress. However, a moderately strong positive association was found between perceived emotional support and SalE/(E + F) (r = .49). Additionally, the final regression analysis revealed a significant negative relationship between educational degree, planned/unplanned pregnancy and SalE/(E + F).Conclusion
Findings suggest a higher metabolization of cortisol to cortisone in pregnant women with higher emotional support. In contrast, higher maternal education and unplanned pregnancy appear to be associated with decreased salivary 11β-HSD2 activity. The current study emphasizes the importance of taking the activity of 11β-HSD2 into account when examining SalF. 相似文献105.
Corbacioglu S Cesaro S Faraci M Valteau-Couanet D Gruhn B Rovelli A Boelens JJ Hewitt A Schrum J Schulz AS Müller I Stein J Wynn R Greil J Sykora KW Matthes-Martin S Führer M O'Meara A Toporski J Sedlacek P Schlegel PG Ehlert K Fasth A Winiarski J Arvidson J Mauz-Körholz C Ozsahin H Schrauder A Bader P Massaro J D'Agostino R Hoyle M Iacobelli M Debatin KM Peters C Dini G 《Lancet》2012,379(9823):1301-1309
106.
Geoffrey A. Rubin Angelo Biviano Jose Dizon Hirad Yarmohammadi Frederick Ehlert Deepak Saluja David A. Rubin John P. Morrow Marc Waase Jeremy Berman Alexander Kushnir Mark P. Abrams Hasan Garan Elaine Y. Wan 《Journal of cardiovascular electrophysiology》2020,31(6):1249-1254
A global coronavirus (COVID‐19) pandemic occurred at the start of 2020 and is already responsible for more than 74 000 deaths worldwide, just over 100 years after the influenza pandemic of 1918. At the center of the crisis is the highly infectious and deadly SARS‐CoV‐2, which has altered everything from individual daily lives to the global economy and our collective consciousness. Aside from the pulmonary manifestations of disease, there are likely to be several electrophysiologic (EP) sequelae of COVID‐19 infection and its treatment, due to consequences of myocarditis and the use of QT‐prolonging drugs. Most crucially, the surge in COVID‐19 positive patients that have already overwhelmed the New York City hospital system requires conservation of hospital resources including personal protective equipment (PPE), reassignment of personnel, and reorganization of institutions, including the EP laboratory. In this proposal, we detail the specific protocol changes that our EP department has adopted during the COVID‐19 pandemic, including performance of only urgent/emergent procedures, after hours/7‐day per week laboratory operation, single attending‐only cases to preserve PPE, appropriate use of PPE, telemedicine and video chat follow‐up appointments, and daily conferences to collectively manage the clinical and ethical dilemmas to come. We discuss also discuss how we perform EP procedures on presumed COVID positive and COVID tested positive patients to highlight issues that others in the EP community may soon face in their own institution as the virus continues to spread nationally and internationally. 相似文献
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An allosteric model for benzodiazepine receptor function 总被引:5,自引:0,他引:5
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Effect of oral melatonin on the procoagulant response to acute psychosocial stress in healthy men: a randomized placebo-controlled study 总被引:1,自引:0,他引:1
Abstract: Acute mental stress is a potent trigger of acute coronary syndromes. Catecholamine-induced hypercoagulability with acute stress contributes to thrombus growth after coronary plaque rupture. Melatonin may diminish catecholamine activity. We hypothesized that melatonin mitigates the acute procoagulant stress response and that this effect is accompanied by a decrease in the stress-induced catecholamine surge. Forty-five healthy young men received a single oral dose of either 3 mg melatonin (n = 24) or placebo medication (n = 21). One hour thereafter, they underwent a standardized short-term psychosocial stressor. Plasma levels of clotting factor VII activity (FVII:C), FVIII:C, fibrinogen, D-dimer, and catecholamines were measured at rest, immediately after stress, and 20 min and 60 min post-stress. The integrated change in D-dimer levels from rest to 60 min post-stress differed between medication groups controlling for demographic and metabolic factors ( P = 0.047, = 0.195). Compared with the melatonin group, the placebo group showed a greater increase in absolute D-dimer levels from rest to immediately post-stress ( P = 0.13; = 0.060) and significant recovery of D-dimer levels from immediately post-stress to 60 min thereafter ( P = 0.007; = 0.174). Stress-induced changes in FVII:C, FVIII:C, fibrinogen, and catecholamines did not significantly differ between groups. Oral melatonin attenuated the stress-induced elevation in the sensitive coagulation activation marker D-dimer without affecting catecholamine activity. The finding provides preliminary support for a protective effect of melatonin in reducing the atherothrombotic risk with acute mental stress. 相似文献