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排序方式: 共有1080条查询结果,搜索用时 15 毫秒
31.
Kristian Bartnes Trude Sildnes Amjid Iqbal Øystein Dahl-Eriksen Thor Trovik Terje Kristian Steigen 《Scandinavian cardiovascular journal : SCJ》2013,47(2):83-86
Objectives. Angiography by selective catheterization is the reference standard for coronary bypass graft patency assessment but carries a risk of serious complications. We have investigated whether 16-slice multidetector spiral computed tomography (MDCT) can substitute for selective angiography. Design. Two to three years after coronary artery bypass grafting, 45 patients with a total of 156 bypasses (100 single and 28 sequential grafts) were examined with both MDCT and conventional selective angiography on the same day. The bypasses were classified as patent, stenotic or occluded. Results. The likelihood ratio for MDCT-detected occlusion was 40, reflecting a fairly high combined sensitivity and specificity. However, 24% of the distal anastomoses could not be evaluated by MDCT, mainly because of respiratory movements, artifacts due to metal clips, and small vessel dimensions. Moreover, seven out of 117 bypasses (6%) deemed evaluable by MDCT were wrongly classified by this method. Conclusions. At present, 16-slice MDCT cannot replace selective angiography for assessment of coronary bypass graft patency since 24% of bypasses could not be evaluated by this method, and an error rate of 6% is unacceptable. 相似文献
32.
Sigmund Skjeldal Finn Lilleås Gunnar Follerås Anna Elisabeth Stenwig Eigil Samset Terje Tillung 《Acta orthopaedica》2013,84(6):637-638
Arterial embolisation with radio-active microspheres was used to measure the proportion of cardiac output to the skeleton and the tibiofibular bone both in unoperated rabbits and in rabbits after tibial osteotomy and subsequent external fixation. The mean uptake of the intact tibiofibula was 0.11 per cent of the cardiac output and, correspondingly, 0.21 per cent after the osteotomy. Maximal uptake occurred 18 days after the operation which was accompanied by a slight decrease in overall skeletal circulation. 相似文献
33.
Claudia Elsner Alessandro D'Ausilio Gustaf Gredebäck Terje Falck-Ytter Luciano Fadiga 《Neuropsychologia》2013,51(3):488-492
We examined the hypothesis that predictive gaze during observation of other people's actions depends on the activation of corresponding action plans in the observer. Using transcranial magnetic stimulation and eye-tracking technology we found that stimulation of the motor hand area, but not of the leg area, slowed gaze predictive behavior (compared to no TMS). This result shows that predictive eye movements to others' action goals depend on a somatotopical recruitment of the observer's motor system. The study provides direct support for the view that a direct matching process implemented in the mirror-neuron system plays a functional role for real-time goal prediction. 相似文献
34.
Pedersen ED Frøyland E Kvissel AK Pharo AM Skålhegg BS Rootwelt T Mollnes TE 《Molecular immunology》2007,44(9):2459-2468
Complement activation can cause tissue damage in cerebral stroke by the release of biologically potent activation products and impaired function of regulatory proteins. We investigated the constitutive and hypoxia-reoxygenation-dependent expression of complement receptor 1 (CD35), membrane cofactor protein (CD46), decay-accelerating factor (CD55), protectin (CD59), and complement C3a and C5a receptors (C3aR and C5aR) on human NT2-N neurons. The effect of hypoxia-reoxygenation on C3d-deposition on neurons and endothelial cells was also investigated. NT2-N neurons were examined by cellular enzyme-linked immunosorbent assay and immunofluorescence microscopy. Endothelial cells were examined by flow cytometry. Three hours 1% or 0.1% hypoxia and 21h reoxygenation with 50% AB-serum were used to investigate the effect of hypoxia-reoxygenation on regulators and C3d-deposition. NT2-N neurons expressed significant amounts of CD59 (Clone H19/Clone BRIC229: p=0.000006/p=0.000003), CD46 (p=0.00006), CD55 (p=0.003) and C3aR (p=0.00003). CD35 and C5aR were not significantly expressed. There were no effects of hypoxia-reoxygenation on any of the regulators or receptors after 1% hypoxia and reoxygenation. However, CD55 (p=0.02) was down-regulated after 0.1% hypoxia and subsequent reoxygenation with AB-serum. There were no difference observed in the C3d-deposition during hypoxia-reoxygenation in either neurons or endothelial cells. In conclusion, human NT2-N neurons constitutively express C3aR, CD46, CD55 and, in particular, CD59. The cells may respond to locally produced C3a and, at the same time, be well protected against complement attack. Although severe hypoxia-reoxygenation may down-regulate CD55 expression, it does not seem to influence C3d-deposition. 相似文献
35.
36.
Izabela Blaszczyk Nazli Poorsafar Foumani Christina Ljungberg Mikael Wiberg 《Toxins》2015,7(11):4645-4654
Botulinum toxin A (BoNT-A) injections for treatment of spasticity in patients with cerebral palsy (CP) have been used for about two decades. The treatment is considered safe but a low frequency of adverse events (AE) has been reported. A good method to report AEs is necessary to verify the safety of the treatment. We decided to use an active surveillance of treatment-induced harm using a questionnaire we created. We studied the incidence of reported AEs and side effects in patients with CP treated with BoNT-A. We investigated the relationship between the incidence of AEs or side effects and gender, age, weight, total dose, dose per body weight, Gross Motor Function Classification System (GMFCS) and number of treated body parts. Seventy-four patients with CP participated in our study. In 54 (51%) of 105 BoNT-A treatments performed in 45 (61%) patients, there were 95 AEs and side effects reported, out of which 50 were generalized and/or focal distant. Severe AEs occurred in three patients (4%), and their BoNT-A treatment was discontinued. Consecutive collection of the AE and side-effect incidence using our questionnaire can increase the safety of BoNT-A treatment in patients with CP. 相似文献
37.
Effect of basis set on electron populations calculated by using Bader's criterion for partitioning electron density between atoms 下载免费PDF全文
Wiberg KB Wendoloski JJ 《Proceedings of the National Academy of Sciences of the United States of America》1981,78(11):6561-6563
The effect of basis set on Bader's criterion for partitioning electron density between atoms is examined. The major effect is on the position of minimum electron density along the bond of interest. The 6-31G** basis leads to the more satisfactory results. The effect of including electron correlation was examined via the use of generalized valence bond wavefunctions. The change in the electron populations was small. The partitioning of electron density is useful in examining the way in which substituents interact with hydrocarbon groups. 相似文献
38.
Harald Vikne Vegard Strøm Are Hugo Pripp Terje Gjøvaag 《Scandinavian journal of medicine & science in sports》2020,30(8):1298-1317
The main objective of this systematic review was to examine the effect of reduced muscle activity on the relative number of type 1 muscle fibers (%) in the human vastus lateralis muscle. Other objectives were changes in type 2A and 2X percentages and muscle fiber cross-sectional area. We conducted systematic literature searches in eight databases and included studies assessing type 1 fiber percentage visualized by ATPase or immunohistochemical staining before and after a period (≥14 days) of reduced muscle activity. The reduced muscle activity models were detraining, leg unloading, and bed rest. Forty-two studies comprising 451 participants were included. Effect sizes were calculated as the mean difference between baseline and follow-up and Generic Inverse Variance tests with random-effects models were used for the weighted summary effect size. Overall, the mean type 1 muscle fiber percentage was significantly reduced after interventions (−1.94%-points, 95% CI [−3.37, −0.51], P = .008), with no significant differences between intervention models (P = .86). Meta-regression showed no effect of study duration on type 1 fiber percentage (P = .98). Conversely, the overall type 2X fiber percentage increased after reduced muscle activity (P < .001). The CSA of the muscle fiber types decreased after the study period (all P-values < 0.001) with greater reductions in type 2 than type 1 fibers (P < .001). The result of this meta-analysis display that the type 1 muscle fiber percentage decrease as a result of reduced muscle activity, although the effect size is relatively small. 相似文献
39.
S. Matthijs Boekholdt G. Kees Hovingh Samia Mora Benoit J. Arsenault Pierre Amarenco Terje R. Pedersen John C. LaRosa David D. Waters David A. DeMicco R. John Simes Antony C. Keech David Colquhoun Graham A. Hitman D. John Betteridge Michael B. Clearfield John R. Downs Helen M. Colhoun Antonio M. Gotto Jr. Paul M. Ridker Scott M. Grundy John J.P. Kastelein 《Journal of the American College of Cardiology》2014
Background
Levels of atherogenic lipoproteins achieved with statin therapy are highly variable, but the consequence of this variability for cardiovascular disease risk is not well-documented.Objectives
The aim of this meta-analysis was to evaluate: 1) the interindividual variability of reductions in low-density lipoprotein cholesterol (LDL-C), non–high-density lipoprotein cholesterol (non-HDL-C), or apolipoprotein B (apoB) levels achieved with statin therapy; 2) the proportion of patients not reaching guideline-recommended lipid levels on high-dose statin therapy; and 3) the association between very low levels of atherogenic lipoproteins achieved with statin therapy and cardiovascular disease risk.Methods
This meta-analysis used individual patient data from 8 randomized controlled statin trials, in which conventional lipids and apolipoproteins were determined in all study participants at baseline and at 1-year follow-up.Results
Among 38,153 patients allocated to statin therapy, a total of 6,286 major cardiovascular events occurred in 5,387 study participants during follow-up. There was large interindividual variability in the reductions of LDL-C, non-HDL-C, and apoB achieved with a fixed statin dose. More than 40% of trial participants assigned to high-dose statin therapy did not reach an LDL-C target <70 mg/dl. Compared with patients who achieved an LDL-C >175 mg/dl, those who reached an LDL-C 75 to <100 mg/dl, 50 to <75 mg/dl, and <50 mg/dl had adjusted hazard ratios for major cardiovascular events of 0.56 (95% confidence interval [CI]: 0.46 to 0.67), 0.51 (95% CI: 0.42 to 0.62), and 0.44 (95% CI: 0.35 to 0.55), respectively. Similar associations were observed for non-HDL-C and apoB.Conclusions
The reductions of LDL-C, non-HDL-C, and apoB levels achieved with statin therapy displayed large interindividual variation. Among trial participants treated with high-dose statin therapy, >40% did not reach an LDL-C target <70 mg/dl. Patients who achieve very low LDL-C levels have a lower risk for major cardiovascular events than do those achieving moderately low levels. 相似文献40.
Stefan Huhnstock Svein Svenningsen Are H Pripp Terje Terjesen Ola Wiig 《Acta orthopaedica》2014,85(5):506-512