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991.
Dr Bernard Sénécail Bernard Menanteau Pierre Quereux 《Surgical and radiologic anatomy : SRA》1979,2(2):181-190
Résumé Ce travail tente de définir une écho-anatomie du foie normal à partir de neuf plans tomographiques de référence, chacun étant caractérisé par la morphologie de la glande hépatique, par son contenu structural et par son environnement topographique.Les auteurs interprètent l'imagerie échographique directement à partir de l'observation macroscopique de coupes anatomiques correspondantes. Ils indiquent que la corrélation anatomo-échographique est satisfaisante et dégagent quelques indications spécifiques pour chacune des incidences. 相似文献
992.
320 patients with essential hypertension divided into three groups (minor, medium and major severty) were studied against 50 normal controls. Plasma renin activity (PRA) was estimated in case of normal and low Na intake, furthermore, of low Na intake in association with administration of chlorothiazide, in the recumbent position as well as at the end of 4-hr walk. The hypertensive group of medium severity (Group II) revealed a significant decrease in PRA, compared with the controls and with the hypertensive group of minor severity (Group I), in each period of observation. A significant increase of PRA in response to insulin hypoglycaemia was demonstrable in all three groups and in the controls, but the increase was of significantly lesser degree in Group II than either in the controls or in Group I. The plasma catecholamine concentrations were found lower in Group II than in the controls and in Group I. An elevation of the plasma catecholamine levels was demonstrable in response to insulin hypeglycaemia, but it was of lesser degree in Group II than a Group I and in the controls. The poor responsiveness of the RAS in Group II is attributed to an inadequate adrenergic activity and to an increased mean arterial pressure in that group, but the higher age of patients and longer duration of hypertensive disease, both characteristic of the group of medium severity, may also effect the renin-angiotensin system. 相似文献
993.
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997.
M D Karvé V M Shamarin I V Vinogradova O N Ankhimiuk N S Kiseleva L P Vorob'eva S P Potapkin 《Patologicheskaia fiziologiia i èksperimental'naia terapiia》1990,(3):35-38
Blood plasma uric acid and urea content and aspartate aminotransferase activity were studied in 177 patients with ischemic heart disease and essential hypertension. It was established that the blood uric acid level did not depend essentially on the transamination processes in patients with ischemic heart disease but was closely connected with transamination processes and amino acid metabolism in patients with essential hypertension. 相似文献
998.
G. R. Brisson P. Boisvert F. Péronnet A. Quirion L. Senécal 《European journal of applied physiology》1989,58(8):816-820
Summary This study was designed to verify if the decrease in blood prolactin (PRL) induced by selective face cooling during exercise
could be part of a response to specific body thermal stress. Five healthy trained male cyclists presenting a significant plasma
PRL elevation to exercise were, on three occasions and at weekly interval, submitted to a submaximal exercise (approx. 65%
) on ergocycle with and without selective face cooling. In absence of face cooling a first trial served to establish reference
values for workload, heart rate and plasma PRL levels, the latter increasing markedly (450% of resting values) in these conditions.
On a second trial but with workload maintained at reference values (222±9 W), a significant bradycardia was observed with
face cooling; furthermore, plasma PRL response to exercise was significantly reduced (to 31% of original response). On a third
trial with face cooling, workload had to be significantly augmented (242±10 W) to maintain heart rate at reference level (78%HR
max); in addition, plasma PRL response to exercise was almost unchanged compared to the reference-value level. The absence of
a significant face cooling-induced decrease in sympathetic tonus, as evaluated through peripheral plasma catecholamines response,
does not indicate a role for the autonomic nervous system in the face cooling-induced reduction of both heart rate and PRL
responses during exercise. Assay of circulating peripheral beta-endorphins could indicate that the face cooling-induced PRL
blunted response does not necessarily involve an opioid mediation. It was concluded that decreased plasma PRL levels could
be associated to bradycardia, hyposudation and peripheral vaso-constriction to constitute an integrated response to face cooling
during thermal stress.
This study was supported by grants from Natural Sciences and Engineering Research Council of Canada and from Régie de la Sécurité
dans les Sports du Québec 相似文献
999.
The site and concentration dependence of the blocking effect of Ba2+ onNecturus gallbladder epithelium has been investigated. A new approach was used which combines time-dependent electrical cell coupling
analysis with intermittently performed measurements of transepithelial and apparent intracellular impedance. From the coupling
pulse data the sum of apical and basolateral membrane conductances is obtained, which is then held constant during fitting
of the impedance data. This combination technique yields more reliable estimates of apical and basolateral membranes resistances
(R
a,R
bl) and of tight junction resistance (R
j) than our previous impedance analysis technique. Using the new approach we have found that luminal Ba2+ concentrations between 0.5 and 1.0 mmol/l increaseR
a with saturation-type kinetics without affectingR
bl andR
j, while higher luminal Ba2+ concentrations progressively increaseR
j. Corresponding effects were observed under serosal Ba2+. The results validate the new impedance analysis approach and demonstrate that millimolar concentrations of Ba2+ block tight junction conductances. Accordingly, Ba2+ can no longer be considered a tool to exclusively alter cell membrane resistances in epithelia. 相似文献
1000.
U Schr?der S Segrén C Gemmefors G Hedlund B Jansson H O Sj?gren C A Borrebaeck 《Journal of immunological methods》1986,93(1):45-53
Magnetically responsive nanoparticles were prepared from enzymatically hydrolysed starch and magnetite. Two different monoclonal antibodies were covalently coupled to the particles. The antibody-coupled particles were in the size range of 100-300 nm and had an iron content of about 60%. Using 100 micrograms of magnetic particles (coupled with monoclonal mouse anti-rat Ig kappa light chain antibody) a very high depletion of surface Ig positive cells (mostly B-cells) from one million rat peripheral blood mononuclear cells could be achieved. The separation efficiency was evaluated by flow cytofluorometric analysis. This technique permits the detection of a small number of surface Ig positive cells among 10,000 negative cells. 相似文献