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151.
Dr. Edward B. Blanchard Ann E. Taylor Mark P. Dentinger 《Applied psychophysiology and biofeedback》1992,17(3):179-202
Data are presented from a prospective clinical replication series of ten consecutive high-medication headache patients who presented for nondrug treatment of their headaches. For the first eight, an attempt was made to withdraw the patients from medication, with the assistance of relaxation training, prior to entering a comprehensive self-regulatory treatment program. For the last two, drug withdrawal accompanied the treatment. Six of the ten patients showed clinically significant reductions in headache activity, which held up over follow-ups of up to 12 months. Psychological tests provide some discrimination between success and failures.This research was supported in part by a grant from NINDS, No. NS-23340. Appreciation is expressed to Dr. Kenneth A. Appelbaum and Ms. Denise Michultka for their roles in this study. 相似文献
152.
Dr. Sue Ann Thompson 《Cell and tissue research》1982,225(1):79-93
Summary Immunoreactive prolactin (IMP) has been localized in the male rat brain using the soluble peroxidase-anti-peroxidase (PAP) technique. In normal untreated animals, reaction product was seen in choroid plexus (CP) and in ependymal cells of the ventricular lining with heaviest concentrations of positively staining cells in the 3rd ventricle near the subcommisural organ (SCO), in the lateral ventricles near the subfornical organ (SFO), and in the 4th ventricle near the area postrema (AP). IMP was also present in numerous ependymal cells resembling tanycytes in the cerebral aqueduct, central canal of the spinal cord at the level of the AP, the organum vasculosum of the lamina terminalis (OVLT) and the floor of the infundibular recess. Immunoreactive cells resembling neurons were localized within the substance of the AP, SCO, and OVLT. IMP was also present in fibers of the zona externa of the median eminence and infundibular stalk; a few cells of the pars tuberalis contained reaction product. Hypophysectomized rats and bromocriptine-treated rats exhibited a similar staining pattern except that bromocriptine treatment eliminated IMP from most CP cells. Hypophysectomy, bromocriptine or estrogen treatment enhanced staining for IMP in cells of the pars tuberalis; estrogen treatment or hypophysectomy produced an increase in the number and distribution of immunoreactive cells as well as increased density of reaction product in cells of the medial habenular nucleus. The functional relevance of prolactin in these locations in the brain, the possible routes of transport of prolactin from the pituitary gland to the central nervous system, and the strong suggestion of extra-pituitary sites of synthesis of a prolactin-like hormone are discussed. 相似文献
153.
ApparentK
s
andV
max values, for the transport byThiobacillus A2 of14C-labelled sucrose, hexoses and pentoses, were estimated using flow dialysis and membrane filtration techniques. Transport systems of varying degrees of specificity could be inferred from the data. For most sugars tested including glucose, fructose and arabinose, there was a close correlation between maximum rate of sugar transport and observed growth rate. Differences in transport rate were sufficient to explain slow and fast growth on glucose by wild type and GF strains ofThiobacillus A2.Abbreviations Butyl PBD
2-(4-tert-butylphenyl)-5-(4-biphenylyl)-1,3,4-oxadiazole
- Tris
tris(hydroxymethyl)-amino-methane
- PEP
phosphoenolpyruvate 相似文献
154.
Mitosis in Mantoniella squamata (Manton and Parke) Desikachary, a small scale-covered green monad, is presented. Organelle replication precedes nuclear division and begins with the replication of the chloroplast. As the chloroplasts separate, the Golgi and flagellar apparatuses divide. The discoid microbody enlarges and becomes ‘V'-shaped, with the arms extending toward depressions in the pyrenoid stalks of the chloroplasts. At prophase, microtubules produced by an amorphous microtubule organizing center enter the nucleus via polar fenestre. The nuclear membrane remains intact. As the chloroplasts migrate further apart, the spindle pole-to-pole distance increases. By metaphase, daughter-cell lobes are discernible as a cleavage furrow, which appears as early as prophase, and begins to incise the cell. A single Golgi apparatus is situated near the spindle pole; the flagellar apparatus lies adjacent to the pole. The cleavage furrow continues to constrict the cell, resulting in a narrowing isthmus containing the elongate microbody, nucleus and a rootlet system connecting the basal bodies of the daughter flagella. At telophase, no extra-nuclear microtubular systems other than the previously observed rootlet are present and the nuclei remain separated from each other. In cells undergoing multiple divisions to produce more than two daughter cells, the orientation of organelles changes somewhat, with the basal bodies and the Golgi apparatus separating daughter nuclei prior to the onset of cytokinesis. The mechanics of mitosis in Mantoniella are compared with other green monads and the evolutionary implications discussed. 相似文献
155.
Seedling dynamics of some cotton grass tussock tundra species during the natural revegetation of small disturbed areas 总被引:2,自引:0,他引:2
The dynamics of seedling establishment, and growth of native cotton grass-tussock tundra species were studied during the natural revegetation of small bare areas excavated in tussock tundra. The seedlings of Eriophorum vaginatum spp. spissum and Carex bigelowii , two sedge species, established most successfully. Few seedlings of nonsedge species emerged with the small disturbances. Most seedling emergence occurred early in the first growing season following the excavation of the bare areas. The density of emerged seedlings was higher in bare areas excavated in the autumn preceding the observations, rather than in bare areas excavated at the start of the first season of observation. After two growing seasons, survival of seedlings was not affected by the time the seedling emerged within the growing season. Eriophorum vaginatum was the most abundant species because it: (1) had the highest seedling emergence rates, particularly early in the growing season: (2) produced more tillers per seedlings; and (3) had a higher growth rate per seedling than C. bigelowii . 相似文献
156.
157.
Sarah Ann Woodin 《Journal of experimental marine biology and ecology》1982,60(1):35-45
Data on the morphology and behavior of five species of spionid polychaete from muddy sand habitats in both the United Kingdom and the northwest coast of North America are presented. The data are consistent with the hypothesis that browsing predation by visual predators is important now and has been important in the evolutionary past. As predicted by such a hypothesis, regenerating individuals are common in all the populations examined. Individuals belonging to species that expose their anterior ends while feeding and/or defecating have cryptic anteriors (Pygospio elegans Claparède, Rhynchospio glutaeus (Ehlers), Malacoceros fuliginosus (Claparède), and Spiophanes bombyx (Claparède)). Individuals belonging to species that do not expose their anteriors while feeding and/or defecating do not have cryptic anteriors (Pseudopolydora kempi (Southern)). Given these data it is still unclear as to how many of the geographic patterns of coloration that have been reported for infauna are associated with the presence of visual predation. Further investigations are suggested. 相似文献
158.
Paul N. Black Carol D. Blair Ann Butcher John L. Capinera George M. Happ 《Journal of invertebrate pathology》1981,38(1):12-21
Physical and chemical parameters of iridescent virus type 29, isolated from the mealworm, Tenebrio molitor, have been analyzed. The icosahedral capsid is 130–135 nm in diameter and is surrounded by a fringe of coarse filaments. The virus has a buoyant density in CsCl of 1.31 g cm?3 and contains 20 to 25 structural proteins as analyzed by isoelectric focusing and SDS-polyacrylamide gel electrophoresis. The DNA has a buoyant density in CsCl of 1.6874 g cm?3 indicating a G + C content of approximately 28%. The lipid components of this virus differ from those of the host cell; the virus contains about 80% cardiolipin and 20% phosphatidyl choline. 相似文献
159.
Quasi-elastic light scattering has been used to measure the change in the translational diffusion coefficient of hemoglobin upon oxygenation and the difference in the diffusion coefficients of oxy- and methemoglobin. The diffusion coefficients of oxy- and methemoglobin were found to be the same within the experimental accuracy of 0.2%, while the diffusion coefficient of oxyhemoglobin tetramers in solution at 13 mg/ml was found to be 0.8% smaller than that of deoxyhemoglobin at the same concentration, when the reversible dissociation of oxyhemoglobin tetramers into dimers was taken into account. In the limit of zero concentration, the oxyhemoglobin diffusion coefficient was found to be 1.5% ± 1.0% smaller than that of deoxyhemoglobin. This result is in very good agreement with what we predict using atomic coordinates to model the liganded and unliganded hemoglobin molecules as ellipsoids of revolution. 相似文献
160.
Regionally Selective Metabolic Effects of Hypoglycemia in Brain 总被引:12,自引:10,他引:2
Robert A. Ratcheson Ann C. Blank James A. Ferrendelli 《Journal of neurochemistry》1981,36(6):1952-1958
Abstract: Regional CNS levels of glucose reserves, glycolytic intermediates, and high-energy phosphate reserves were measured in insulin-treated, hypoglycemic rats and correlated with EEG activity. Intravenous administration of insulin to paralyzed, ventilated animals causes concomitant reduction of blood glucose levels and progressive abnormality and eventual loss of EEG activity. In all regions of brain examined, glucose and glycogen levels decrease until they are essentially depleted, and glucose-6-phosphate and fructose-1,6-biphosphate fall approximately 80%. Pyruvate levels decrease 50% in cerebral cortex and brain stem and a lesser amount in striatum, hippocampus, thalamus, and cerebellum. Lactate levels fall 50–60% in all regions except cerebellum, where no change is observed. ATP and phosphocreatine levels remain normal until the EEG is isoelectric, and then decrease in all regions except cerebellum. These results demonstrate that hypoglycemia does not have a uniform effect on brain glucose and energy metabolism, and cerebellum seems to be relatively protected. 相似文献