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Effect of dietary selenium and vitamin E on the biomechanical properties of rabbit bones 总被引:1,自引:0,他引:1
Summary It is generally agreed that combined deficiency of selenium and vitamin E leads to several abnormalities including Kashin-Beck disease which is an endemic and chronic degenerative osteoarthrosis. The abnormalities can be reversed by the administration of various forms of selenium and vitamin E.The present study was designed to investigate the effects of dietary selenium and vitamin E on bone tissue and on the biomechanical properties of bone. Young rabbits of both sexes were fed with either a selenium- and vitamin E-adequate diet (control group), or a selenium- and vitamin E-deficient diet or a selenium-excess diet. The selenium-deficient diet resulted in a significant decrease in plasma selenium level and the selenium-excess diet resulted in a significant increase in the plasma selenium level with respect to the corresponding control values (p<0.05). The diets did not affect the blood cell counts considerably but erythrocyte glutathione peroxidase activity increased (decreased) relatively when the plasma selenium level increased (decreased) (p<0.05). The light microscopic investigations of the bone tissues of the two experimental groups indicate that the findings of the present work are compatible with osteomalacia. The biomechanical properties of the bones from the three groups were determined experimentally with bending tests. Both the Se-and vitamin E-deficient diet and the Se-excess diet decreased the biomechanical strength of the bones significantly while the bones belonging to the control group always had the largest modulus of elasticity (p<0.05). 相似文献
3.
Selenium improves cardiac function by attenuating the activation of NF-kappaB due to ischemia-reperfusion injury 总被引:1,自引:0,他引:1
Turan B Saini HK Zhang M Prajapati D Elimban V Dhalla NS 《Antioxidants & redox signaling》2005,7(9-10):1388-1397
Although selenium, an essential trace element and a component of glutathione peroxidase, is known to protect the heart from ischemia-reperfusion (I/R)-induced injury, the mechanisms of this protection are not fully understood. For this purpose, isolated rat hearts were subjected to 30 min of global ischemia followed by 30 min of reperfusion; sodium selenite (25-1,000 nM) was added in the perfusion medium 10 min prior to ischemia, as well as during reperfusion. Selenium caused a dose-dependent improvement in cardiac performance and attenuated the decrease in the ratio of reduced glutathione to oxidized glutathione, as well as the increased level of malondialdehyde in I/R heart. Elevated ratios of nuclear factor-kappaB (NF-kappaB) in particulate and cytosolic fraction and of phosphorylated NF-kappaB and total NF-kappaB in I/R hearts were reduced by selenium. Cardiac dysfunction in hearts perfused with xanthine plus xanthine oxidase mixture, as well as hydrogen peroxide, or subjected to Ca2+ paradox was also attenuated by selenium. These data suggest that selenium protects the heart against I/R injury due to its action on the redox state and deactivation of NF-kappaB in I/R hearts. 相似文献
4.
Ashraf Imam Cihan Karatas Nesimi Mecit Munci Kalayoglu Turan Kanmaz 《Transplantation proceedings》2021,53(5):1622-1625
BackgroundCardiovascular complication is one of the leading causes of mortality after liver transplantation (LT). Thus, a thorough cardiac evaluation is a must before proceeding to a liver transplant surgery. Percutaneous coronary intervention (PCI) with stent and to a lesser extent coronary artery bypass grafting (CABG) are both valuable treatment options for patients with coronary artery disease.MethodsA retrospective, single-center study that included patients who underwent cardiac intervention and subsequent LT for end-stage liver disease. All patients who had PCI or CABG were included in the study.ResultsTwenty-nine adult patients out of 51 had a cardiac intervention before liver transplantation. Twenty-four patients had a diagnostic PCI, 3 patients had therapeutic PCI with stent, and 2 had failed PCI and proceeded to CABG before liver transplant. The mean age of the patients was 60.5 years. There were 24 men. All patients had cirrhosis. The 2 CABG cases were done during the same admission with a 13- and 18-day interval between the CABG and the transplantation. Both cases were live-related liver transplantation. No mortality was reported.ConclusionIn case of PCI failure, CABG may be a valuable and safe treatment option for cirrhotic patients as a preparation for liver transplantation. Live donor liver transplantation may be a good back-up for those patients in case they develop hepatic decompensation. 相似文献
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E E Buyukbayrak C Turan O Unal R Dansuk B Cengizo?lu 《The journal of maternal-fetal & neonatal medicine》2004,15(2):120-125
OBJECTIVE: The purpose of this study was to determine the reliability of the vaginal washing-fluid prolactin assay for the diagnosis of premature rupture of membranes (PROM) and to determine a diagnostic cut-off value. STUDY DESIGN: Seventy pregnant women between 11 and 40 weeks of gestation who were admitted with vaginal fluid leakage were included in the study group, and were then further subdivided into two subgroups according to amniotic fluid pooling and nitrazine paper test results. Group 1 was the 'confirmed PROM group', positive for both pooling and nitrazine (38 patients). Group 2 was the 'suspected but unconfirmed PROM group' which had possible pooling and/or nitrazine (32 patients). Seventy pregnant women between 11 and 40 weeks of gestation without any complaint and complication were included in the control group (group 3). All patients underwent vaginal washing-fluid sampling and prolactin level determination. For the statistical analysis one-way analysis of variance, Tukey multiple comparison test, chi2 test and receiver operating characteristic (ROC) curve analysis were used. RESULTS: Geometric mean values of vaginal washing-fluid prolactin levels were 616.59 microIU/ml for group 1, 23.98 microIU/ml for group 2 and 10 microIU/ml for group 3 (p < 0.0001). The optimal diagnostic cut-off value was found to be 30 microIU/ml with 95% sensitivity, 78% specificity, 84% positive predictive value, 93% negative predictive value, 87% accuracy and 11.30 relative risk. CONCLUSIONS: We recommend vaginal washing-fluid prolactin level determination as an alternative diagnostic method for PROM. 相似文献
7.
Onur Turan Nilgün Ylmaz Demirci AK Güntülü ule Akay Ülkü Aka Aktürk Semra Bilaerolu Funda Cokun Ouz Kktürk Arzu Mirici Cengiz
zdemir Nazan en Ülkü Yilmaz 《African health sciences》2022,22(1):532
BackgroundCoronavirus disease 2019 (covid-19), which causes a pandemic in the world, has started to appear in turkey since march 2020. Healthcare workers are at the top of the groups most at risk for covid-19 infection, which can have a negative impact on psychological state.ObjectivesIt was aimed to evaluate anxiety and depression levels among healthcare workers.Methodsthis cross-sectional study performed via an online survey in april 2020. Participants answered questions about sociodemographic features, personal views and experiences about covid-19 and the hospital anxiety and depression scale (hads).ResultsA total of 300 healthcare workers,193 men and 107 women, participated in the survey. According to hads, 44.6% of participants scored above anxiety and 68.2% scored above depression cut-off points. Being younger than 50 and taking care of covid-19 patients in hospitals were independently associated with anxiety risk. Female gender, young age (less than 50) and having comorbidity were independent risk factors for depression.ConclusionHealthcare workers were at high risk of anxiety and depression during covid-19 outbreak. For this reason, psychological support should be given, especially to the group with high risk. 相似文献
8.
Barutcu I Sezgin AT Gullu H Topal E Acikgoz N Ozdemir R 《International journal of cardiology》2004,94(2-3):177-180
BACKGROUND: Isolated myocardial bridging (MB) often is considered to be an unimportant angiographic finding; however, its association with cardiovascular event has been shown. In this study we aimed to assess exercise-induced electrocardiographic (ECG) changes and susceptibility to arrhythmia in patients with MB. METHOD: 21 consecutive patients who had angiographically proven MB (group I) and 25 subjects (group II) who had normal coronary arteries underwent exercise test using Bruce protocol. Before and after the exercise test the changes in QT interval duration and dispersion were compared. RESULTS: Baseline characteristics of both groups were similar. Heart rate significantly increased after exercise test in both groups. In group I, after exercise mean QT(max) and QT(min) durations did not change significantly compared to baseline values, respectively. (QT(max): 411+/-20 vs. 421+/-18 ms, p>0.05 and QT(min): 380+/-12 vs. 378+/-10 ms, p>0.05). However, following exercise test QT dispersion (QT(d)) and corrected QT dispersion (QT(cd)) significantly increased when compared to baseline values, respectively. (34+/-13 vs. 66+/-14 ms, p<0.05 and 37+/-14 vs. 69+/-17 ms, p<0.05) On the other hand, in control group QT(max) and QT(min) durations, QT(c) and QT(cd) did not change significantly compared to baseline values, respectively. (QT(max): 408+/-18 vs. 412+/-17 ms, p>0.05 and QT(min): 390+/-11 vs. 387+/-10 ms, p>0.05; QT(d): 25+/-14 vs. 31+/-16 ms, p>0.05; QT(cd): 27+/-15 vs. 33+/-17 ms, p>0.05). CONCLUSION: Treadmill exercise test significantly increased QT dispersion in patients with MB. This increase may result from exercise-induced ischemia at the area perfused by bridged artery. 相似文献
9.
Extracts of Ginkgo biloba (EGb) are among the most prescribed drugs in France and Germany. EGb is claimed to be effective in peripheral arterial disorders and in "cerebral insufficiency." The mechanism of action is not yet well understood. Three of the ingredients of the extract have been isolated and found to be pharmacologically active, but which one alone or in combination is responsible for clinical effects is unknown. The recommended daily dose (3 x 40 mg extract) is based more on empirical data than on clinical dose-findings studies. However, despite these, according to double-blind, placebo-controlled clinical trials, EGb has therapeutic effects, at least, on the diagnostic entity of "cerebral insufficiency," which is used in Europe as synonymous with early dementia. To determine whether EGb has significant pharmacological effects on the human brain, a pharmacodynamic study was conducted using the Quantitative Pharmacoelectroencephalogram (QPEEG(R)) method. It was established that the pharmacological effects (based on a predetermined 7.5--13.0-Hz alpha frequency band in a computer-analyzed electroencephalogram = CEEG(R)) of EGb on the central nervous system (CNS) are significantly different than placebo, and the high and low doses could be discriminated from each other. The 120-mg, but particularly the 240-mg, single doses showed the most consistent CNS effects with an earlier onset (1 h) and longer duration (7 h). Furthermore, it was established that the electrophysiological effects of EGb in CNS are similar to those of well-known cognitive activators such as "nootropics" as well as tacrine, the only marketed "antidementia" drug currently available in the United States. 相似文献
10.
Yaprak Seçil MD Cem Ünde MD Yeşim Yetimalar Beckmann MD Yasemin Turan Bozkaya MD Filiz Özerkan MD Mustafa Başoğlu MD 《Pain practice》2010,10(3):222-227
Migraine attacks are characterized by headaches associated with neurological, gastrointestinal, and autonomic symptoms. A relationship between migraine and hypertension or hypotension is controversial. In this study, we aimed to determine if blood pressure changes were related to migraine attacks. From the outpatient clinic of our neurology department, 62 normotensive migraine patients with and without aura were chosen for study in accordance with the International Headache Society 2004 criteria. A questionnaire including general and specific questions was given to the patients to be filled out during 6 consequent migraine attacks. The patients received a fully automatic digital brachial upper arm sphygmomanometer (Omron M 4‐1) to measure the changes in their blood pressure during attacks. The patients were asked to record their blood pressure changes 3 times: (1) just before or very early, (2) during (when headache peaks), and (3) 1 hour after the attack. Twenty‐three of the 62 patients (57 women, 5 men) had migraine with aura (22 women and 1 man), and 39 of them did not have aura (35 women and 4 men). There was no statistically significant difference between systolic and diastolic values obtained before or very early, during the peak level, and 1 hour after the end of the attacks (P > 0.05). Although diastolic hypotensive values were not different statistically between groups, when all the patients were considered, diastolic hypotensive values were detected in a considerable number of patients (a total of 115 measurements). In this normotensive migrainous population, we observed that diastolic hypotension before or very early, during, and after migraine attack was the most significant result (5.1%). Although it was not statistically significant, the total number of hypotensive values was remarkable. 相似文献