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51.
Summary The wettability of leaf surface in maize seedlings may vary according to the genotypes,Gl orgl. Techniques in electron microscopy have made it possible to resolve the fine structure of theGl—surface as contrasted with those ofgl
1,gl
2,gl
3, andgl
H
. The normal surface, shows minute projections which are almost absent in the glossy surface of young seedlingsgl
1; thegl
2,gl
3 andgl
H
seedlings present a somewhat intermediate situation.With 1 Figure in the Text 相似文献
52.
53.
Edwin L. Ball Albert C. Dornbush George M. Sieger F. E. Stirn James C. Vitucci Joseph F. Weidenheimer 《Applied microbiology》1961,9(4):269-272
Data are presented to show that β-propiolactone when properly applied is a very effective agent for sterilization of regenerated collagen sutures. The chemical sterilization is accomplished with little or none of the loss in strength encountered with heat sterilization. The finished sterile suture is obtained without any harmful residue that might be detrimental to the patient. 相似文献
54.
ELECTRON MICROSCOPY OF THE OXYNTIC CELL IN THE GASTRIC GLANDS OF THE BULLFROG (RANA CATESBIANA) : I. The Non-Acid-Secreting Gastric Mucosa 总被引:5,自引:4,他引:1 下载免费PDF全文
Albert W. Sedar 《The Journal of cell biology》1961,9(1):1-18
The fine structure of the oxyntic cell from the gastric glands of the bullfrog was studied in lead hydroxide—stained sections of gastric mucosa fixed in buffered osmium tetroxide and embedded in n-butyl methacrylate. The oxyntic cell in non-acid-secreting stomachs (gastric juice pH, 7.4–7.8) is characterized by: (a) numerous closely packed smooth surfaced vesicular and tubular profiles disposed randomly in the cell; some of these elements show interconnections making it possible to identify this component with smooth surfaced endoplasmic reticula of certain other cell types, (b) a small percentage of rough surfaced profiles characteristic of endoplasmic reticula possessing RNP particles on the outer membrane surfaces, (c) a Golgi complex consisting of multiple isolated non-polarized arrays of smooth surfaced parallel elongated profiles and associated vesicular elements, (d) a sparse granular component (140 A) scattered freely in the cytoplasmic matrix, (e) numerous mitochondria with a dense matrix and containing an unusually large number of closely approximated cristae, (f) a number of zymogen granules consisting of either a dense body limited by a membrane or surrounded by a halo of less dense material which is in turn limited by a membrane, and (g) a number of granules (~260 A) containing several smaller granules (~80 A) identified presumably as glycogen. Intracellular canaliculi were not observed. Instead the free surface of the oxyntic cell facing the lumen of the gastric gland shows a complicated plication of the plasma membrane. Intercellular canaliculi are seen frequently between adjacent oxyntic cells. The walls of these canaliculi are made up of folded and ruffled cell membranes. The basal surface of the cell also exhibited this type of configuration. Occasional smooth surfaced profiles are seen communicating with the free surface, the wall of an intercellular canaliculus, or the basal surface of the cell. Although nerve endings were not found in association with oxyntic cells, unmyelinated nerves were observed in the vicinity of the gastric glands. 相似文献
55.
56.
Marcel J. Dallemagne Ch. Albert Baud Peter W. Morgenthaler 《Histochemistry and cell biology》1959,1(3):185-189
Résumé Etude qualitative et quantitative du marquage in vitro de coupes d'os compact. Détermination du rôle joué par les processus de diffusion, d'adsorption et d'échange dans ces phénomènes.
Avec 2 Figures dans le Texte
La partie expérimentale de ce travail a pu être réalisée grâce à des subsides fournis par l'European Office of the Air Research and Development Command [contrat no AF 61 (514) 1175], par l'Institut Interuniversitaire Belge des Sciences Nucléaires, et par la Commission pour la Science Atomique du Fonds National Suisse de la Recherche Scientifique. 相似文献
Zusammenfassung Qualitative und quantitative Studie der in vitro-Markierung von Schliffen aus Knochen-Compacta. Bestimmung der Rolle der Diffusions-, Adsorptions- und Austauschprozesse für diese Vorgänge.
Avec 2 Figures dans le Texte
La partie expérimentale de ce travail a pu être réalisée grâce à des subsides fournis par l'European Office of the Air Research and Development Command [contrat no AF 61 (514) 1175], par l'Institut Interuniversitaire Belge des Sciences Nucléaires, et par la Commission pour la Science Atomique du Fonds National Suisse de la Recherche Scientifique. 相似文献
57.
The presence of thymidilate kinase in human erythrocytes 总被引:1,自引:0,他引:1
58.
F. William Blaisdell Albert D. Hall Arthur N. Thomas Steven J. Ross 《The Western journal of medicine》1965,103(5):321-329
Three hundred patients with cerebrovascular occlusive disease have had cerebral angiographic examination at the Veterans Administration Hospital, San Francisco, in the last five years. The present technique consists of preliminary visualization of the aortic arch and the major extracranial branches, followed by selective study of the subclavian and carotid arteries as necessary for evaluation of the intracranial circulation.Nine major complications occurred (an over-all incidence of 3 per cent). Two patients died after angiography and seven had major neurologic deficits persisting for more than 24 hours. Three of these patients had permanent damage, but four recovered completely.One-third of the patients had extracranial disease and one-third had intracranial disease. No significant lesion was found in the remainder. In the 212 patients with lesions, multiple lesions were common, the average number being three. Six patients had brain tumors and five had aneurysms.The mechanism of the stroke could be ascertained readily in most of the patients, but the extent of the disease and the resulting symptoms varied considerably. Several patients with occlusion of most of the cerebral vessels had minimal symptoms, while others had catastrophic symptoms but only minimal findings at arteriography. 相似文献
59.
Abdominal distension alters regional pleural pressures and chest wall mechanics in pigs in vivo 总被引:4,自引:0,他引:4
T Mutoh W J Lamm L J Embree J Hildebrandt R K Albert 《Journal of applied physiology》1991,70(6):2611-2618
Abdominal distension (AD) occurs in pregnancy and is also commonly seen in patients with ascites from various causes. Because the abdomen forms part of the "chest wall," the purpose of this study was to clarify the effects of AD on ventilatory mechanics. Airway pressure, four (vertical) regional pleural pressures, and abdominal pressure were measured in five anesthetized, paralyzed, and ventilated upright pigs. The effects of AD on the lung and chest wall were studied by inflating a liquid-filled balloon placed in the abdominal cavity. Respiratory system, chest wall, and lung pressure-volume (PV) relationships were measured on deflation from total lung capacity to residual volume, as well as in the tidal breathing range, before and 15 min after abdominal pressure was raised. Increasing abdominal pressure from 3 to 15 cmH2O decreased total lung capacity and functional residual capacity by approximately 40% and shifted the respiratory system and chest wall PV curves downward and to the right. Much smaller downward shifts in lung deflation curves were seen, with no change in the transdiaphragmatic PV relationship. All regional pleural pressures increased (became less negative) and, in the dependent region, approached 0 cmH2O at functional residual capacity. Tidal compliances of the respiratory system, chest wall, and lung were decreased 43, 42, and 48%, respectively. AD markedly alters respiratory system mechanics primarily by "stiffening" the diaphragm/abdomen part of the chest wall and secondarily by restricting lung expansion, thus shifting the lung PV curve as seen after chest strapping. The less negative pleural pressures in the dependent lung regions suggest that nonuniformities of ventilation could also be accentuated and gas exchange impaired by AD. 相似文献
60.
F. Solimano G. I. Bischi M. Bianchi L. Rossi M. Magnani 《Bulletin of mathematical biology》1990,52(6):785-796
A non-linear three-compartment model is proposed to describe a new strategy for the administration of 2′,3′-dideoxycytidine
(ddCyd) in the treatment of HIV infections. The drug is injected after having been encapsulated in a non-diffusible form (ddCMP)
into erythrocytes. Nummerical solutions show that by this treatment the highest ddCyd blood concentration is strongly reduced
and in turn its toxicity, while long-lasting therapeutic effect is assured. The model is compared with experimental data in
vitro. 相似文献