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101.
102.
103.
Sequences from higher primates orthologous to the human Xp/Yp telomere junction region reveal gross rearrangements and high levels of divergence 总被引:2,自引:2,他引:2
A high level of sequence polymorphism combined with linkage disequilibrium
has created a limited number of highly diverged haplotypes across the human
Xp/Yp telomere junction region. To gain insight into the unusual genetic
characteristics of this region, we have examined the orthologous sequences
in the common chimpanzee (Pan troglodytes ), the gorilla (Gorilla gorilla)
and the orang-utan (Pongo pygmaeus). Divergence from the human Xp/Yp
sequence is higher (average 2.6-fold) than that observed at other loci. The
position of the human Xp/Yp telomere is unique, as additional sequences are
present at this location in the other three species. These included an
array of subterminal satellite in the chimpanzee and, in the gorilla a
small interstitial array of telomere-like repeats followed by sequences
with strong homology to the human 18p subterminal region. In the
orang-utan, two alleles with different structures were identified. These
differ by the presence or absence of a short interspersed nuclear element
(SINE) sequence just proximal to long arrays of telomere-like repeat
sequences that probably represent the proximal end of the orang-utan Xp/Yp
telomere. In addition, a high level of sequence divergence between the two
orang-utan structures was identified. This divergence is similar to that
observed between the human Xp/Yp telomere-adjacent haplotypes. The high
sequence divergence and evidence of gross rearrangements indicate that the
Xp/Yp telomeric region has evolved faster than the rest of the genome.
相似文献
104.
Stimuli were delivered to 12 subjects in a sequence that included regularly occurring standard tone pips, random warning tone pips, and random while noise bursts. Half the noise bursts were preceded by warning tones (high probability), and half were not (low probability). There were four runs, each having one of two noise burst intensities, and each having the warning tone and noise bursts either both task-relevant to a reaction time task or both task irrelevant. Event-related potentials (ERPs) were obtained by signal averaging in F2, C2, P2 and eye leads. The P3 to the warning tone was largest in P, and was not affected by task relevance. CNVs preceded all the high probability noise bursts. These CNVs had an amplitude of 5μV even when the bursts were task irrelevant. Low probability noise bursts elicited larger P3s in all leads for the task-irrelevant condition, but only in Pz for the task-relevant conditions. In Cz, the amplitudes of NI. P2, and P3 to the high probability. task-relevant noise bursts correlated with the amplitude of the preceding CNV. 相似文献
105.
Jina V. Han Dipika V. Patel David Squirrell Charles NJ. McGhee 《Clinical & experimental ophthalmology》2019,47(3):346-356
Pseudophakic cystoid macular oedema (PCMO) remains a significant cause of compromised postoperative vision in contemporary cataract surgery. Well‐established risk factors include intraoperative complications such as posterior capsule rupture and preoperative factors including: diabetes mellitus, uveitis, retinal vein occlusion, epiretinal membrane. The role of topical glaucoma medications in PCMO continues to be debated. Current treatment strategies largely target suppression of inflammation. Topical NSAIDs remain the mainstay in prophylaxis and treatment of PCMO. Topical corticosteroids are commonly used as monotherapy or in combination with NSAIDs. Unfortunately, high‐quality trials are notably lacking for other PCMO treatment modalities such as: periocular corticosteroids, orbital floor triamcinolone, intravitreal triamcinolone, corticosteroid implants, intravitreal bevacizumab and pars‐plana vitrectomy. A lack of consistency in defining PCMO and resolution of PCMO explains why even large systematic reviews may come to contradictory conclusions. This review explores the varied contemporary evidence‐base in relation to the aetiology, diagnosis, prophylaxis and treatment of PCMO. 相似文献
106.
NJ Lees AJP Rosenberg AI Hurtado-Doce J Jones N Marczin M Zeriouh A Weymann A Sabashnikov AR Simon AF Popov 《Journal of artificial organs》2016,19(4):399-402
Sepsis-induced cardiogenic shock in combination with severe acute respiratory failure represents a life-threatening combination that is often refractory to the conventional methods of treatment. We describe the case of a 33-year-old patient who developed acute cardiovascular collapse and ARDS secondary to superinfection of Panton–Valentine leukocidin—positive Staphylococcus aureus and H1N1 pneumonia who underwent successful combination therapy for severe sepsis-related cardiomyopathy and respiratory failure using extracorporeal membrane oxygenation and cytokine adsorption therapy. 相似文献
107.
108.
Synaptic depression creates a switch that controls the frequency of an oscillatory circuit
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Farzan Nadim Yair Manor Nancy Kopell Eve Marder 《Proceedings of the National Academy of Sciences of the United States of America》1999,96(14):8206-8211
Synaptic depression is a form of short-term plasticity exhibited by many synapses. Nonetheless, the functional significance of synaptic depression in oscillatory networks is not well understood. We show that, in a recurrent inhibitory network that includes an intrinsic oscillator, synaptic depression can give rise to two distinct modes of network operation. When the maximal conductance of the depressing synapse is small, the oscillation period is determined by the oscillator component. Increasing the maximal conductance beyond a threshold value activates a positive-feedback mechanism that greatly enhances the synaptic strength. In this mode, the oscillation period is determined by the strength and dynamics of the depressing synapse. Because of the regenerative nature of the feedback mechanism, the circuit can be switched from one mode of operation to another by a very small change in the maximal conductance of the depressing synapse. Our model was inspired by experimental work on the pyloric network of the lobster. The pyloric network produces a simple motor rhythm generated by a pacemaker neuron that receives feedback inhibition from a depressing synapse. In some preparations, elimination of the synapse had no effect on the period of the rhythm, whereas in other preparations, there was a significant decrease in the period. We propose that the pyloric network can operate in either of the two modes suggested by the model, depending on the maximal conductance of the depressing synapse. 相似文献
109.
B Tseveenjav JI Virtanen NJ Wang E Widström 《International journal of dental hygiene》2009,7(1):17-22
Abstract: Aim: The aim was to compare the working profiles of Finnish and Norwegian dental hygienists in public and private practice. To this end, we compared the procedures performed, the type of patients and the time devoted to different tasks. Subjects and methods: A questionnaire survey was originally conducted among a representative sample of dental hygienists in Finland (n = 595) and all authorized dental hygienists in Norway (n = 1 138) in 2004. The questionnaires collected data on the dental hygienists’ age, gender, year of graduation, working experience, work sector (private or public), working time spent on different activities and patient groups. The questionnaire also assessed how frequently the dental hygienists performed 25 different treatment measures. Results: The Norwegian dental hygienists spent 45.4% of their clinical time on check‐ups, whereas the Finns spent 49.9% of their time scaling. Dental hygienists in Finland and Norway working in the public sector spent 42.9% and 74.6% of their working time dealing with children and youth respectively. Conclusions: The working profiles of dental hygienists in Finland and Norway were quite similar, although differences in distribution by activities, type of patients and treatment measures do exist. The main activity of the dental hygienists was clinical work. The most commonly practised clinical activity among Finnish dental hygienists was scaling, and among Norwegians, check‐ups. Public dental hygienists in both countries dealt mainly with children and youths. Oral hygiene instruction was the most commonly reported treatment measure among both Finns and Norwegians. 相似文献
110.
A. VIK E. B. MATHIESEN J. BROX T. WILSGAARD I. NJØLSTAD L. JØRGENSEN J.‐B. HANSEN 《Journal of thrombosis and haemostasis》2011,9(4):638-644
Summary. Background: Osteoprotegerin (OPG) concentration in serum is associated with the presence and severity of atherosclerosis. Objective: To investigate the association between serum osteoprotegerin and the risk of a future myocardial infarction, ischemic stroke and mortality in a general population. Patients/methods: OPG was measured in serum collected from 6265 subjects recruited from a general population without a prior myocardial infarction and ischemic stroke (the Tromsø Study). Incident myocardial infarction, ischemic stroke and mortality were registered during follow‐up. Cox regression models were used to estimate crude and adjusted hazard ratios and 95% confidence intervals (HR; 95% CI). Results: There were 575 myocardial infarctions, 284 ischemic strokes and 824 deaths (146 deaths as a result of ischemic heart disease, 78 deaths because of stroke and 600 deaths due to other causes) in the cohort during a median of 10.6 years of follow‐up. Serum OPG (per SD [1.13 ng mL?1] increase in OPG) was associated with an increased risk of a myocardial infarction (1.20; 1.11–1.31), ischemic stroke (1.32; 1.18–1.47), total mortality (1.34; 1.26–1.42), death because of ischemic heart disease, (1.35; 1.18–1.54), stroke (1.44; 1.19–1.75) and non‐vascular causes (1.31; 1.22–1.41) after adjustment for age, gender, current smoking, systolic blood pressure, body mass index, high density lipoprotein cholesterol, total cholesterol, creatinine, high sensitivity C‐reactive protein (CRP) and diabetes mellitus or HbA1c > 6.1%. No association was detected between OPG and incident hemorrhagic stroke (1.02; 0.73–1.43). Conclusions: Serum OPG was associated with future risk of myocardial infarction, ischemic stroke, total mortality, mortality of ischemic heart disease, stroke and of non‐vascular causes independent of traditional cardiovascular risk factors. 相似文献