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941.
硝苯啶的光解分析法及其在透皮吸收研究中的应用 总被引:1,自引:0,他引:1
A new method of analysis for low concentrations nifedipine was developed according to the principle of a photodegradation analytical method that has been reported by the authors previously, and was used to study percutaneous absorption. The absorbance of sample solution was measured before and after light irradiation at 237 nm for 2 h. In this method, calibration graph was linear in the range of 1~20μg/ml for △A237. The average recovery for nifedipine was 98.80%. No interference from propylene glycol, azone, m-nifedipine, nitrendipine, verapamil and propranolol was observed. It is shown that azone can promote markedly percutaneous absorption of nifedipine. 相似文献
942.
This is a study of the relationship between the site of infarctionand both risk factors and in-hospital outcome in 745 consecutivepatients admitted with a first myocardial infarction. Patients with anterior infarctions were significantly more likelynever to have smoked than patients with inferior infarctions.They had a higher prevalence of hypertension and a higher meancholesterol level. In hospital prognosis was worse in anteriorinfarctions, with significantly higher rates of death and complications.Atrioventricular blocks were more common in inferior infarctions.Non-Q-wave infarctions had a lower incidence of complicationsthan Q-wave infarctions. There was no difference in risk factorlevels between Q-wave and non-Q-wave infarctions. Anterior andinferior infarctions were of similar size. Non-Q-wave infarctionswere significantly smaller.A logistic regression showed a negativerelationship between in-hospital mortality and smoking, anda positive one with peak cardiac enzyme levels. Any effect ofsite of infarction on mortality was eliminated when correctedfor these factors. Our data indicate that the adverse prognosisassociated with anterior myocardial infarction is related todifferences in aetiology rather than to infarction size. 相似文献
943.
Orr JF 《Irish journal of medical science》2003,172(4):209-213
Background This paper cites the development of the principles of photoelastic stress analysis, contemporary to the life of Samuel Haughton.
Subsequent studies of bone and joint replacements are discussed, with reference to hypotheses regarding bone, including the
coincidence of trabecular structure with principal stresses. Issues regarding assumptions of homogeneous and isotropic properties
in photoelastic modelling are acknowledged.
Aim Awareness of photoelastic methods is often through the visual appeal of the coloured fringe patterns. The aim of this paper
is to complement this awareness by demonstration of the quantitative analyses that may be conducted through biomechanical
examples.
Methods Examples of new pseudo three-dimensional model analyses are presented together with a method for photoelastic study of cancellous
bone, which entails novel procedures for preparation of replicate models and for optical evaluation of fringes.
Conclusion Photoelastic analysis offers novel solutions to studies in biomechanics, which are facilitated by contemporary modelling
materials. 相似文献
944.
945.
946.
947.
Blanchard F; Pitard V; Taupin JL; Raher S; Hallet MM; Moreau JF; Godard A; Jacques Y 《International immunology》1997,9(12):1775-1784
The binding and functional properties of a set of six mAb directed against
the human gp190 [leukemia inhibitory factor (LIF) receptor] signal
transducing molecule were determined. Each of the antibodies reacted with a
distinct epitope on gp190 expressed either by gp190- transfected Chinese
hamster ovary cells or by the LIF receptor-positive choriocarcinoma JAR
cell line. Two of the antibodies (1B4 and 6E6) had binding stoichiometries
that were approximately 2-fold lower than those of other mAb (10B2, 12D9
and 7G7), suggesting either that gp190 is present as a pre-associated
homodimer in the cell membrane or that part of gp190 is pre-associated with
another component. Two mAb (1C7 and 1B4) were found to inhibit LIF binding
on the two cell types studied. On JAR cells, this inhibition was, however,
restricted to the high- affinity LIF component, suggesting different modes
of LIF engagement with the low- and high-affinity receptor species. mAb 1C7
and 1B4 were also found to synergize for inhibiting LIF high-affinity
binding. This synergy also extended to the inhibition of LIF- or oncostatin
M (OSM)- induced proliferation of a Ba/F3 cell line co-transfected with
human gp130 and gp190. However, this mAb combination inhibited LIF- but not
OSM-induced haptoglobin secretion by HepG2 cells, suggesting that whereas
haptoglobin secretion induced by LIF involves gp130/gp190 common LIF/OSM
type I receptors, that induced by OSM mainly involves type II OSM
receptors.
相似文献
948.
S. J. BOURKE R. CARTER K. ANDERSON J. BOYD S. KING B. DOUGLAS G. BOYD 《Clinical and experimental allergy》1989,19(6):629-632
The aim of the study was to assess the degree of airways involvement in non-smoking subjects with extrinsic allergic alveolitis resulting from pigeon-derived antigens. Two hundred and eight pigeon fanciers completed a questionnaire of symptoms, performed spirometry on a Vitalograph Compact spirometer and had IgG antibody to pigeon gamma-globulin measured. Eighty fanciers had the acute form of pigeon fanciers' lung (PFL) and these subjects were less likely to be current smokers (P less than 0.001). Subjects with PFL had a higher prevalence of chronic bronchitis (P less than 0.001), large airways (P = 0.014) and peripheral airways obstruction (P less than 0.001). The prevalence of chronic bronchitis and peripheral airways obstruction increased significantly as the level of antibody to pigeon gamma-globulin rose. Peripheral airways obstruction, as manifest by a reduced FEF25-75%, was the most common abnormality found. Airways disease is an important feature of the acute form of PFL and consists of a hypersecretory disorder in the form of chronic bronchitis and of obstructive airways disease particularly affecting the peripheral airways. 相似文献
949.
Length of the follicular phase, time of insemination, coital rate and the sex of offspring 总被引:2,自引:2,他引:0
The penetrability of cervical mucus improves over the follicular phase.
When the length of the follicular phase varies due to variation in the
timing of the luteinizing hormone surge, mucus penetrability will also
improve as the phase lengthens. As selection for Y spermatozoa decreases
with improvements in mucus penetrability, sex ratios at conception should
decline in longer follicular phases. Sex ratios should also decline as the
time of insemination approaches ovulation unless hormonally-induced
improvements in penetrability are reduced by the debris left by earlier
inseminations.
相似文献
950.
Three-dimensional reconstruction of the human central sulcus reveals a morphological correlate of the hand area 总被引:2,自引:1,他引:1
Sastre-Janer FA; Regis J; Belin P; Mangin JF; Dormont D; Masure MC; Remy P; Frouin V; Samson Y 《Cerebral cortex (New York, N.Y. : 1991)》1998,8(7):641-647
One way to improve our understanding of cortical anatomy is to visualize
the three-dimensional (3D) shape of the cerebral sulci which is normally
hidden. Here, we reconstructed the 3D morphology of the central sulcus (CS)
in 17 normal subjects, using conventional magnetic resonance images and
dedicated software. We found that the 3D morphology was remarkably
consistent in all central sulci. Our analyses revealed three different
regions (upper, middle and lower), which were easily identifiable by
morphological criteria and sharply interconnected in the reconstructed CS.
These morphological regions appear to have a strong functional
significance, since the middle region corresponded precisely to the 'hand
area', as verified by hand vibration positron emission tomography
activation studies in eight cases. These data suggest that the 3D anatomy
of the cerebral cortex may facilitate sulcal recognition, and sulcal
subdivision into smaller morphological elements, bearing remarkable
relationships with functional cortical maps.
相似文献