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排序方式: 共有4116条查询结果,搜索用时 31 毫秒
81.
Delles C Zimmerli LU McGrane DJ Koh-Tan CH Pathi VL McKay AJ Steedman T Dargie HJ Hamilton CA Dominiczak AF 《Journal of hypertension》2008,26(5):946-955
OBJECTIVES: Oxidative stress causes endothelial dysfunction and plays a major role in the pathogenesis of cardiovascular disease. Increased vascular stiffness is an intermediate phenotype in the development of cardiovascular disease. We hypothesized that vascular stiffness is partially determined by oxidative stress. METHODS: We examined 163 participants out of whom 80 had coronary artery disease. Vascular stiffness was assessed by pulse wave analysis, pulse wave velocity and measurement of aortic compliance by cardiac MRI. Circulating markers of oxidative stress and vascular superoxide generation in saphenous vein were measured. RESULTS: After adjustment for age, sex, BMI, heart rate, blood pressure and lipids only carotid-femoral pulse wave velocity and aortic compliance were different between patients and control group. Aortic compliance was reduced (11.4 +/- 6.3 vs. 13.9 +/- 7.3 ml x 10(-3) per mmHg; P = 0.035) and vascular superoxide generation increased (1.01 +/- 0.45 vs. 0.76 +/- 0.44 nmol/mg per min; P = 0.035) in patients with coronary artery disease compared with those without. In a multiple stepwise regression analysis, aortic compliance was determined by age (P < 0.001) and vascular superoxide production (P = 0.033). CYBA C242T and NOS3 G894T polymorphisms had additive effects on vascular superoxide generation (P = 0.026) and xanthine oxidase activity was increased in patients with CAD (P = 0.043). Genetic factors (P = 0.033) and xanthine oxidase activity (P < 0.001) were also related to aortic compliance. CONCLUSION: By measuring vascular superoxide generation and aortic compliance using cardiac MRI, we demonstrated a functional relationship between oxidative stress and vascular stiffness. Patients identified with high levels of vascular stiffness are most likely to benefit from strategies to reduce vascular oxidative stress. 相似文献
82.
W. Dean Klinkenberg Robert J. Calsyn Gary A. Morse Suzanne McCudden Tracey L. Richmond Gary K. Burger 《AIDS and behavior》2002,6(4):295-307
In this paper we present data from a study of the consistency of recall of several sexual and drug-using behaviors gathered from face-to-face interviews with homeless persons who have dual diagnosis (severe mental illness plus a substance use disorder). Factors associated with inconsistent reporting are also examined. One hundred and thirty-three individuals participating in a longitudinal study of HIV risk behaviors were recruited for a retrospective recall study. Participants were completing monthly interviews that included assessments of sexual behaviors and drug use. Participants completed an additional interview using the same instruments and were randomly assigned to a 3- or 6-month recall condition; the data from the additional interview were correlated with the regular, monthly interviews. Results indicated that reports of sexual and substance-using behaviors were generally reported consistently for both 3- and 6-month recall periods; however, coefficients for the 3-month interval were generally better than those for the 6-month interval. One exception was that protected intercourse was generally not reported consistently. Inconsistent reporting of sexual and drug-using behaviors was associated with the severity of substance abuse; inconsistent reporting of sexual behaviors was also associated with African-American race. Our data suggest that a 3-month recall interval is generally superior to a 6-month interval for persons with severe mental illness. 相似文献
83.
Vergara C Tsai YJ Grant AV Rafaels N Gao L Hand T Stockton M Campbell M Mercado D Faruque M Dunston G Beaty TH Oliveira RR Ponte EV Cruz AA Carvalho E Araujo MI Watson H Schleimer RP Caraballo L Nickel RG Mathias RA Barnes KC 《American journal of respiratory and critical care medicine》2008,178(10):1017-1022
84.
Stone AF Mendall MA Kaski JC Edger TM Risley P Poloniecki J Camm AJ Northfield TC 《Circulation》2002,106(10):1219-1223
85.
Tracey A. Milligan 《The American journal of medicine》2021,134(7):840-847
The diagnosis and treatment of seizures and epilepsy is a common task of the physician. Approximately 1 in 10 people will have a seizure during their lifetime. Epilepsy is the tendency to have unprovoked seizures. Epilepsy is the fourth most common neurological disorder and affects 1 in 26 people in the United States and 65 million people worldwide. Evaluation of a patient presenting with a seizure involves excluding an underlying neurologic or medical condition, classifying the seizure type and determining if the patient has epilepsy. Proper treatment requires accurate diagnosis of the epilepsy type and syndrome and use of a medication that is effective and without adverse effects. Most patients can achieve complete seizure control with medication, but if medication is unsuccessful, surgical treatment can be an option. Special situations in the care of people with epilepsy include status epilepticus, women with epilepsy, the older adult, and safety issues. 相似文献
86.
Tymms Kathleen Butcher Belinda E. Sletten Tracey L. Smith Tegan O’Sullivan Catherine Littlejohn Geoffrey Sadler Ricky Tronnberg Rebecca Griffiths Hedley 《Clinical rheumatology》2022,41(4):1105-1114
Clinical Rheumatology - Sleep disturbance and fatigue are commonly reported in ankylosing spondylitis (AS) but specific prevalence and the relationship to disease control are unknown. This... 相似文献
87.
ICAM-1 regulates neutrophil adhesion and transcellular migration of TNF-alpha-activated vascular endothelium under flow 总被引:15,自引:2,他引:15
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In vivo, leukocyte transendothelial migration (TEM) occurs at endothelial cell junctions (paracellular) and nonjunctional (transcellular) locations, whereas in vitro models report that TEM is mostly paracellular. The mechanisms that control the route of leukocyte TEM remain unknown. Here we tested the hypothesis that elevated intercellular adhesion molecule-1 (ICAM-1) expression regulates the location of polymorphonuclear leukocyte (PMN) TEM. We used an in vitro flow model of tumor necrosis factor-alpha (TNF-alpha)-activated human umbilical vein endothelium cells (HUVECs) or an HUVEC cell line transfected with ICAM-1GFP (green fluorescent protein) and live-cell fluorescence microscopy to quantify the location of PMN adhesion and TEM. We observed robust transcellular TEM with TNF-alpha-activated HUVECs and ICAM-1GFP immortalized HUVECS (iHUVECs). In contrast, primary CD3+ T lymphocytes exclusively used a paracellular route. Endothelial ICAM-1 was identified as essential for both paracellular and transcellular PMN transmigration, and interfering with ICAM-1 cytoplasmic tail function preferentially reduced transcellular TEM. We also found that ICAM-1 surface density and distribution as well as endothelial cell shape contributed to transcellular TEM. In summary, ICAM-1 promotes junctional and nonjunctional TEM across inflamed vascular endothelium via distinct cytoplasmic tail associations. 相似文献
88.
Pharmacological modulation of pain-related brain activity during normal and central sensitization states in humans 总被引:6,自引:0,他引:6
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Iannetti GD Zambreanu L Wise RG Buchanan TJ Huggins JP Smart TS Vennart W Tracey I 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(50):18195-18200
Abnormal processing of somatosensory inputs in the central nervous system (central sensitization) is the mechanism accounting for the enhanced pain sensitivity in the skin surrounding tissue injury (secondary hyperalgesia). Secondary hyperalgesia shares clinical characteristics with neurogenic hyperalgesia in patients with neuropathic pain. Abnormal brain responses to somatosensory stimuli have been found in patients with hyperalgesia as well as in normal subjects during experimental central sensitization. The aim of this study was to assess the effects of gabapentin, a drug effective in neuropathic pain patients, on brain processing of nociceptive information in normal and central sensitization states. Using functional magnetic resonance imaging (fMRI) in normal volunteers, we studied the gabapentin-induced modulation of brain activity in response to nociceptive mechanical stimulation of normal skin and capsaicin-induced secondary hyperalgesia. The dose of gabapentin was 1,800 mg per os, in a single administration. We found that (i) gabapentin reduced the activations in the bilateral operculoinsular cortex, independently of the presence of central sensitization; (ii) gabapentin reduced the activation in the brainstem, only during central sensitization; (iii) gabapentin suppressed stimulus-induced deactivations, only during central sensitization; this effect was more robust than the effect on brain activation. The observed drug-induced effects were not due to changes in the baseline fMRI signal. These findings indicate that gabapentin has a measurable antinociceptive effect and a stronger antihyperalgesic effect most evident in the brain areas undergoing deactivation, thus supporting the concept that gabapentin is more effective in modulating nociceptive transmission when central sensitization is present. 相似文献
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90.