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排序方式: 共有893条查询结果,搜索用时 15 毫秒
1.
Patrick E. Barta Richard E. Powers Elizabeth H. Aylward Gary A. Chase Gordon J. Harris Peter V. Rabins Larry E. Tune Godfrey D. Pearlson 《Psychiatry Research: Neuroimaging》1997,68(2-3):65-75
Volumes of medial and lateral temporal lobe structures were assessed using magnetic resonance imaging (MRI) in 11 patients with late-life onset schizophrenia (LOS), 18 normal elderly controls and 12 patients with moderate cognitive impairment due to Alzheimer's disease (AD) who had no non-cognitive symptoms. While both patient groups has smaller volumes of several medial temporal regions (e.g. entorhinal cortex, left hippocampus), schizophrenics had significantly smaller anterior superior temporal gyri (STG) than normal controls, but AD patients did not. We have previously demonstrated anterior STG volume to be reduced in early life onset schizophrenia. 相似文献
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GP SCHWAB AL BLUM E BODNER B DALLEMAGNE K GLASER H KOOP F PACE W RÖSCH JR SIEWERT G WETSCHER 《Journal of gastroenterology and hepatology》1997,12(12):785-789
Gastroesophageal reflux disease (GERD) is the most common disease of the upper gastrointestinal tract. With the introduction of proton pump inhibitors medical treatment of GERD has been significantly improved. However, the development of laparoscopic antireflux surgery resulted in an increasing interest of surgeons in this disease. An interactive meeting was organized in order to develop an agreement between gastoenterologists and surgeons regarding therapeutic decisions and this is the main topic of this paper. 相似文献
5.
Philip Aylward 《Internal medicine journal》1997,27(4):501-503
Fibrinolytic therapy substantially reduces mortality from acute myocardial infarction. Patient selection is, however, important. The patient must present within 12 hours of the onset ofischaemic symptoms, have definite ECG changes of ST elevation or left bundle branch block and no contraindications. The major contraindications are those for risk of an intracerebral bleed, recent stroke, intracranial tumour or risk of a major systemic bleed. Age and hypertension are not contraindications but may modify the regimen used.
Heparin is required with recombinant tissue plasminogen activator but is optional with streptokinase.
The recent COBALT trial suggests that the accelerated weight related t-PA regimen given over 90 minutes is more satisfactory than double bolus t-PA. However, inpatients under 75 years of age, the two regimens were equivalent.
For patients suffering acute myocardial infarction, practitioners should now individualise choice of therapy, rather than give the same cocktail to all patients. The choice of regimen will depend on the cardiac risk, the stroke risk, the bleeding risk and the cost. 相似文献
Heparin is required with recombinant tissue plasminogen activator but is optional with streptokinase.
The recent COBALT trial suggests that the accelerated weight related t-PA regimen given over 90 minutes is more satisfactory than double bolus t-PA. However, inpatients under 75 years of age, the two regimens were equivalent.
For patients suffering acute myocardial infarction, practitioners should now individualise choice of therapy, rather than give the same cocktail to all patients. The choice of regimen will depend on the cardiac risk, the stroke risk, the bleeding risk and the cost. 相似文献
6.
G. W. Aylward Vaegan F. A. Billson 《Documenta ophthalmologica. Advances in ophthalmology》1989,73(3):275-283
Pattern electroretinograms (PERGs) were recorded from two normal human subjects in response to various spatial frequencies and stimulus areas. The maximum stimulus area was 75° × 86° which was achieved by using a standard TV monitor and a reduced viewing distance. The amplitude of the PERG increased with area in an approximately logarithmic fashion over the range investigated. The explanation relates to non-linearities of the stimulus, the retinal image and neural processing. The wide-angle PERG may be useful in the assessment of retinal diseases affecting the mid-peripheral inner retina, such as diabetic retinopathy. 相似文献
7.
Low-artifact intravascular devices: MR imaging evaluation 总被引:2,自引:0,他引:2
Teitelbaum GP; Ortega HV; Vinitski S; Stern H; Tsuruda JS; Mitchell DG; Rifkin MD; Bradley WG Jr 《Radiology》1988,168(3):713-719
Flow-phantom magnetic resonance (MR) imaging, with use of both spin-echo (SE) and gradient-echo (GRE) techniques at 1.5 T, was performed on the percutaneous Greenfield (beta-III titanium alloy [TMA wire]), Amplatz (MP32-N alloy), and Simon nitinol filters and TMA wire facsimiles of the bird's nest, Gunther, new retrievable, and Amplatz vena caval filters. SE imaging allowed detection of thrombi as small as 5 X 5 mm trapped within the percutaneous Greenfield, Simon nitinol, and TMA-wire facsimile filters; with the MP32-N Amplatz filter, a larger volume of thrombus (10 X 20-mm clots) was necessary for clot detection. GRE imaging allowed detection of intraluminal tilting of the percutaneous Greenfield and facsimile Amplatz (TMA-wire) filters. GRE imaging was useful for demonstrating postfilter turbulence due to clots, which was greatest for the Amplatz filter. Imaging of facsimile vascular devices made of tantalum or TMA wire did not cause the severe "black-hole" MR artifacts typical of the stainless-steel devices. SE and GRE imaging were very useful for determining caval patency in two patients with previously placed Mobin-Uddin filters. Noninvasive MR evaluation of blood vessels in the presence of a variety of low-artifact intravascular devices appears feasible. 相似文献
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9.
Sequence comparison of human and yeast telomeres identifies structurally distinct subtelomeric domains 总被引:6,自引:2,他引:6
Flint J; Bates GP; Clark K; Dorman A; Willingham D; Roe BA; Micklem G; Higgs DR; Louis EJ 《Human molecular genetics》1997,6(8):1305-1313
We have sequenced and compared DNA from the ends of three human
chromosomes: 4p, 16p and 22q. In all cases the pro-terminal regions are
subdivided by degenerate (TTAGGG)n repeats into distal and proximal sub-
domains with entirely different patterns of homology to other chromosome
ends. The distal regions contain numerous, short (<2 kb) segments of
interrupted homology to many other human telomeric regions. The proximal
regions show much longer (approximately 10-40 kb) uninterrupted homology to
a few chromosome ends. A comparison of all yeast subtelomeric regions
indicates that they too are subdivided by degenerate TTAGGG repeats into
distal and proximal sub-domains with similarly different patterns of
identity to other non-homologous chromosome ends. Sequence comparisons
indicate that the distal and proximal sub-domains do not interact with each
other and that they interact quite differently with the corresponding
regions on other, non- homologous, chromosomes. These findings suggest that
the degenerate TTAGGG repeats identify a previously unrecognized,
evolutionarily conserved boundary between remarkably different subtelomeric
domains.
相似文献
10.
MRI volumes of the hippocampus and amygdala in adults with Down's syndrome with and without dementia 总被引:4,自引:0,他引:4
Aylward EH Li Q Honeycutt NA Warren AC Pulsifer MB Barta PE Chan MD Smith PD Jerram M Pearlson GD 《The American journal of psychiatry》1999,156(4):564-568
OBJECTIVE: This study sought to determine whether volumes of the hippocampus and amygdala are disproportionately smaller in subjects with Down's syndrome than in normal comparison subjects and whether volume reduction is greater in Down's syndrome subjects with dementia. METHOD: The subjects were 25 adults with Down's syndrome (eight with dementia) and 25 cognitively normal adults who were individually matched on age, sex, and race. Magnetic resonance imaging measures included volumes of the hippocampus, amygdala, and total brain. Nineteen of the Down's syndrome subjects had follow-up scans (interscan interval = 9-41 months). RESULTS: Nondemented Down's syndrome subjects had significantly smaller volumes of the hippocampus, but not the amygdala, than their comparison subjects, even when total brain volume was controlled for. Volumes of both the hippocampus and the amygdala were smaller in the demented Down's syndrome subjects than in their comparison subjects, even when total brain volume was controlled for. Age was not correlated with volume of the hippocampus or amygdala among the nondemented Down's syndrome subjects and the comparison subjects; age was correlated with volume of the amygdala, but not the hippocampus, among the Down's syndrome subjects with dementia. Changes in volume over time were not statistically significant for either the demented or the nondemented subjects. CONCLUSIONS: Hippocampal volume, while disproportionately small for brain size in individuals with Down's syndrome, remains fairly constant through the fifth decade of life in those without dementia. All subjects over age 50 who had Down's syndrome demonstrated volume reduction in the hippocampus as well as clinical signs of dementia. Dementia was also associated with volume reductions in the amygdala that exceeded reductions in total brain volume. 相似文献