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991.
Prada C Puga J Pérez-Méndez L López R Ramírez G 《The European journal of neuroscience》1991,3(6):559-569
Chick embryo retinas were labelled in ovo by single injections of [3H]thymidine at selected times between days 2 and 12 of incubation. Embryos were later removed, at different stages of development, and the retinas processed for autoradiography of either serial sections or dissociated cell preparations. Analysis of unlabelled cells shows that neurogenesis starts, on day 2 of incubation, in a dorsotemporal area of the central retina, close to the posterior pole and to the optic nerve head. A gradient of neurogenesis spreads from this central area to the periphery, where neurogenesis ends, shortly after day 12, when the last few bipolar cells withdraw from the cell cycle. Additional dorsal-to-ventral and temporal-to-nasal gradients can be discerned in our autoradiographs. In all retinal sectors, ganglion cells start first to withdraw from the cell cycle, followed, with substantial overlapping, by amacrine, horizontal, photoreceptor plus Müller, and bipolar neuroblasts. Ganglion cells are also the first to reach the 50% level of unlabelled cells, followed this time by horizontal, photoreceptor, amacrine, Müller and bipolar cells. Finally, 100% levels of unlabelled cell populations are attained simultaneously by ganglion, horizontal and photoreceptor cells, followed by amacrine, then by Müller, and last by bipolar cells. Although all classes of neurons, in varying proportions, are being produced most of the time, our results also demonstrate that, in any given retinal area, the first cells leaving the cycle are determined to become ganglion cells, and the last ones bipolar cells, and not other types. 相似文献
992.
Results of surgical treatment of hepatic hydatidosis: Current therapeutic modifications 总被引:8,自引:2,他引:6
E. Moreno González M.D. P. Rico Selas M.D. Bercedo Martínez M.D. I. García García M.D. F. Palma Carazo M.D. M. Hidalgo Pascual M.D. 《World journal of surgery》1991,15(2):254-263
Hepatic hydatidosis is an endemic disease that affects vast segments of the populations of various countries in the Mediterranean region, South America, the Pacific, and temperate zone nations that possess large numbers of sheep. Four hundred and ten patients bearing 561 hydatid cysts were treated at 2 major hospitals in Madrid, Spain in the period 1974–1989. In order to establish the modifications in diagnostic and therapeutic management introduced as a result of modernization of our clinical facilities and improved technological standards, they were divided into 2 groups: group A corresponded to the period 1974–1984, and group B, corresponded to the period 1985–1989. Since no effective parasiticide agent is available, hepatic hydatidosis must be treated surgically. Today's better knowledge and advancements in liver surgery have made it possible to extirpate the cyst completely with little risk and improved results; hepatic resection should only be considered in exceptional cases; aspiration, drainage procedures, or partial resections of the cyst yield inferior results. We have had no relapse of the hydatid disease in the liver or in any other abdominal site.
Resumen La hidatidosis hepática es una enfermedad endémica que afecta a vastos segmentas de las poblaciones de diversos países de la región mediterránea, Sur América, el Pacífico, y las naciones de las zonas templadas que mantienen grandes rebanos de ovejas. Cuatrocientos diez pacientes con 561 quistes hidatídicos fueron tratados en 2 grandes hospitales de Madrid, España en el período 1974–1989. Con el propósito de establecer las modificaciones en el manejo diagnóstico y terapéutico ocurridas como resultado de la modernización de nuestras facilidades clínicas y de superiores estándares tecnológicos, dividimos la población total de estos pacientes en 2 grandes grupos: grupo A, correspondiente al período 1974–1984, y grupo B, correspondiente al período 1985–1989. Puesto que no existe un agente parasitocida efectivo, la hidatidosis hepática debe ser tratada quirúrgicamente. El mejor conocimiento actual y el avance en la cirugía hepática han hecho posible la extirpatión completa del quiste con bajo riesgo y mejores resultados; la resection hepática debe ser considerada sólo en casos excepcionales; la aspiración, los procedimientos de drenaje o las resecciones parciales del quiste se asocian con malos resultados. En nuestra experiencia no hemos tenido recurrencia de la enfermedad ni en el hígado ni en otros órganos.
Résumé Le kyste hydatique du foie est une maladie endémique qui touche une partie importante de la population dans différents pays de la région méditerranéenne, en Amérique du Sud, dans le Pacifique, et dans les pays de la zone tempérée qui ont beaucoup de moutons. Quatre cent dix patients porteurs de 561 kystes hydatiques ont été traités dans les deux plus grands hôpitaux de Madrid en Espagne de 1974 à 1989. Pour mesurer les progrès dans le diagnostic et le traitement dus à la modernisation de notre équipement médical et à une meilleure technologie, les patients ont été divisés en 2 groupes chronologiques: groupe A de 1974 à 1984 et groupe B de 1985 à 1989. Comme il n'y a pas actuellement de médicament efficace contre ce parasite, on doit traiter par la chirurgie le kyste hydatique. Aujourd'hui, les connaissances plus étendues et les progrès dans la chirurgie du foie permettent d'enlever complètement le kyste avec peu de risques et avec de meilleurs résultats; la résection du foie ne doit être envisagée que dans de rares cas. Les procédés d'aspiration ou de drainage ou les résections partielles du kyste donne des résultats moins bons. Nous n'avons pas eu de récidive du kyste hydatique, ni au foie ni dans une autre localisation péritonéale.相似文献
993.
A simple auto-evaluation sheet is presented for the proper assessment of the patient's condition after surgery. Stress is
put not only on weight loss, but on other important factors as well. 相似文献
994.
995.
Holzenberger M Martín-Crespo RM Vicent D Ruiz-Torres A 《Archives of gerontology and geriatrics》1991,13(1):89-101
Severe dietary restriction delays the physical development of rodents and leads to adult animals of reduced body size but significantly increased life expectancy. We tried to find a similar relationship in human populations using demographical and statistical methods. We show for the total Spanish male population that the mean adult body height reliably reflects the regional living and nutritional conditions. This relation does not only hold for todays socioeconomic data but can also be reproduced using data on family income in the mid 19th century. We calculated the mean height of young men liable to the military service around 1860 and determined their longevity retrospectively using posterior census data. This was done separately for all the Spanish provinces. The linear regression between both parameters manifests a statistically highly significant relationship: the smaller the mean height at age 18 in a province, the higher the chance for people living there to reach high chronological ages. Migrational movements, selection, mortality due to epidemics or unreliability of the population censuses can be largely ruled out as explications for the described correlation. Furthermore, we determined the secular growth trend in Spain for the last 130 years. From 1860 to 1920 the mean height increased by 2.7 cm, from 1920 to 1987 by another 9.8 cm. Since 1950 the trend is above 2 cm per decade country-wide. From 1974 onwards it amounts to 2.89 +/- 0.17. Such high values were worldwide looked upon as isolated cases found only in geographically and socially isolated population subgroups during very limited periods. 相似文献
996.
Public Health System accepts "New Public Health" only in a theoretical way, since in the practice essential modifications to get "Health For All-2000" aims are not implemented. It is necessary to look "bridge-heads" that permit to introduce changes gradually to reorganize Health Services. In the present article, different alternatives are analyzed, all of them giving priority to the programmes that consider Health as a natural resource. These programmes can be "Governmental Programmes" so Health policies coming from the Health Department can be assumed by the others Public Administration Departments. 相似文献
997.
R. Pascual J. F. Horga P. Sánchez-García A. G. García 《Naunyn-Schmiedeberg's archives of pharmacology》1977,301(1):57-64
Summary The effects of ionophore X537A on the release of 3H-noradrenaline and its metabolites from the superfused guinea-pig left atrium were investigated. Concentrations of ionophore of 10 and 30 M greatly increased the release of tritium. Of the total increase in radioactivity elicited by X537A 44% was accounted for as noradrenaline and 50% was due to deaminated metabolites. The ionophore-evoked release of tritium was independent of the extracellular calcium ions and was not affected by agents which modify calcium movements such as verapamil, ryanodine, ruthenium red and tetracaine. X537A released 3H-noradrenaline from extragranular sites in MAO-inhibited atria from reserpine-treated animals and this release was also calcium independent. It is concluded that the ability of X537A to release noradrenaline from vesicular or cytoplasmic sites is not related to its ability to couple with and transport calcium ions through membranes. The ionophore might modify the ionic distribution outside and inside the neuronal membrane which would lead to leakage of the transmitter. 相似文献
998.
Zusammenfassung Berichtet wird über eine zufällige tödliche Ioxynilvergiftung einschließlich der pathologisch-anatomischen Befunde und einer Methode zur Isolierung von Ioxynil in der eingenommenen Flüssigkeit und im Sektionsmaterial, Ioxynil wurde in der eingenommenen Flüssigkeit IR- und NMR-spektroskopisch nachgewiesen und UV-spektrophotometrisch bestimmt. Im biologischen Material wurde Ioxynil dünnschichtchromatographisch und IR-spektroskopisch nachgewiesen. Die Ioxynilbestimmung im Blutserum wurde mit direkter Densitometrie des Dünnschichtchromatogramms durchgeführt.Herrn Doz. MUDr. et JUDr. Lubomír Neoral, CSc. zum 50. Geburtstag imánek, CSc., Fachassistenten des Institutes für medizinische Chemie der Palacký Universität in Olomouc. 相似文献
999.
1000.
Dr. L. Stárka CSc Dr. R. Hampl CSc Dr. M. Bičíková Dr. J. Obenberger CSc 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1976,199(3):261-266
Summary The occurrence of testosterone, estrone, and estradiol-17 in aqueous humor and vitreous body of the rabbit eye was demonstrated. The identity of the steroid hormones was confirmed by their chromatographic properties, microreactions, and radiochemically by crystallization to constant specific activity of their labeled acetates. The levels of testosterone and estrogens in rabbit male and female plasma, aqueous, and vitreous were determined by radioimmunologic assay. The concentrations of the steroid hormones in plasma are higher than in aqueous and vitreous. However, testosterone in aqueous circulates in free form and lacks the binding to sexual hormone-binding globulin as in plasma.
Zusammenfassung Bericht über das Vorkommen von Testosteron, Oestron und Oestradiol-17 im Kammerwasser und Glasörper des Kaninchenauges. Die Art der Steroide wurde mittels Chromatographie, Mikroreaktionen und radiochemisch ermittelt. Der Testosteron- und Oestrogenspiegel im männlichen und weiblichen Kaninchenplasma, im Kammerwasser und Glaskörper wurde radioimmunologisch bestimmt. Die Plasmakonzentration der Steroidhormone lag höher als diejenige im Kammerwasser oder Glaskörper. Testosteron zirkuliert jedoch im Kammerwasser in freier Form, im Plasma dagegen ist es überwiegend an Sexualhormonebindende Globuline gebunden.相似文献