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61.
Zusammenfassung Der Waldrapp verfügt als soziale Vogelart über Verhaltensweisen des Gruppen- wie Paarkontaktes, die durch Veränderung von Körperumriß und Färbung unbefiederter Hautstellen verstärkt werden können: Grüßen, Imponieren, Aggressivverhalten (auch bei Nestlingen), Beschwichtigen, soziale Körperpflege, Kopula, Nestbau-Verhalten, Paarsitzen. Für das Zusammenspiel der Kolonie wichtig sind Grüßen, verschiedene Formen des Imponierens und ritualisierte Aggressionshandlungen. Das Fortpflanzungsgeschehen synchronisieren soziale Gefiederpflege, Kopulationen (bzw. Scheinkopulae) und Nestbauhandlungen. Das Paarsitzen, besonders deutlich außerhalb der Brutperiode, zeigt vermutlich Monogamie an.Das Lautrepertoire, eintönig für das menschliche Ohr, ist individuell variabel.Eine Besonderheit der Waldrappe ist auch die Nestlings-Aggressivität. Nestgeschwister trachten, einander durch Schnabelhiebe in eine Beschwichtigungshaltung zu drängen und so am Betteln zu hindern. Das Verhalten erlischt bei Erreichen eines Gewichtes von ca. 800 g, zugleich mit dem Abflachen der Wachstumskurve. Da Waldrappe ab dem ersten Ei brüten, überleben untergewichtige Letztgeschlüpfte (Nesthäkchen) bei ausreichendem Nahrungsangebot aufgrund ihrer länger anhaltenden Aggressivität.
Social behaviour of the Bald IbisGeronticus eremita — observations at the Alpenzoo, Innsbruck
Summary As a social bird the Bald Ibis shows behaviour patterns for group contact as well as for pair contact: greeting, display, aggressive behaviour of adults and sibling competition, appeasement behaviour, social preening, nesting behaviour, and Paarsitzen (spatial bond). Some of them may be reinforced by changing body-shape and colour of unfeathered skin. Greeting, some forms of display and ritualized aggressions are important for normal intraspecific interactions. Social preening, copulations (false copulae also) and nesting behaviour do not only stimulate the partner, they also synchronize activity within a colony. Paarsitzen might indicate longer lasting monogamy. The vocal inventory is rather uniform, but some calls may vary individually. — The Bald Ibis shows a strong sibling competition. Siblings force to prevent each other to gape by violent pecking and thus releasing appeasement behaviour. Sibling competition stops with about 800 g at the end of the period of rapid body growth. As the Bald Ibis is breeding with the first egg, this behaviour may allow survival of the runt because of its longer lasting aggressivity when there is sufficient food supply.相似文献
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C. Rebekah Hand Marcia O. Burns Ellen Ireland 《Applied psychophysiology and biofeedback》1979,4(2):171-181
An EMG biofeedback program was developed for a 56-year-old Parkinsonism patient who exhibited pathological lip hypertonia and retraction. The program was designed to achieve the following goals: (1) to demonstrate a reduction in postural lip hypertonicity and (2) to demonstrate a reduction in lip hypertonicity during a series of increasingly complex speech activities. To achieve the first goal, contrastive tasks of full contraction and relaxation were utilized. Each posture was sustained while voltage measurements were made at specifici intervals. Procedures to modify lip retraction during speech included five tasks in which the patient was to monitor the audio feedback signal. The tasks involved: prolongation of a neutral vowel, consonant-vowel combinations, monosyllabic words, sentences, and a paragraph-reading task. Data collected over six biofeedback sessions are presented. Trend analyses showed consistent muscular reduction within each task. The following explanations for the decrease in the patient's hypertonicity were discussed: (1) reduction of anisometric contraction, (2) reduction of isometric contraction, (3) relearning of agonistic-antagonistic muscle balance.This research was supported in part by the University of Tennessee Neuropathology Services Program. 相似文献
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The action of xanthine oxidase upon acetaldehyde or xanthine at pH 10.2 has been shown to be accompanied by substantial accumulation of O2? during the first few minutes of the reaction. H2O2 decreases this accumulation of O2? presumably because of the Haber-Weiss reaction () and very small amounts of superoxide dismutase eliminate it. This accumulation of O2? was demonstrated in terms of a burst of reduction of cytochrome , seen when the latter compound was added after aerobic preincubation of xanthine oxidase with its substrate. The kinetic peculiarities of the luminescence seen in the presence of luminol, which previously led to the proposal of H2O4?, can now be satisfactorily explained entirely on the basis of known radical intermediates. 相似文献
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Summary This communication examines the question of phylogenetic congruency- i.e., whether or not the branching order of evolutionary trees is independent of the protein studied. It was found that trees constructed for birds on the basis of immunological comparison of their transferrins, albumins, and ovalbumins agree approximately with a published tree based on the amino acid sequences of their lysozymesc.
This congruency is especially noteworthy with respect to the phylogenetic position of the chachalaca, a Mexican bird classified on morphological grounds in the family Cracidae of the order Galliformes. At the protein level, this species differs as much from non-cracid galliform birds as does the duck, which belongs to another order. Despite the organismal similarity between cracid and non-cracid galliform birds, the molecular relationship is remote. If this contrast between organismal and molecular results had been based on comparative studies with only lysozyme, one could have ascribed the contrast to the possibility that chachalaca lysozyme was paralogous, rather than orthologous, to the other bird lysozymesc. Examination of several proteins is thus desirable in cases of possible paralogy.This work was supported in part by grants GB-42028X from NSF and GM-21509 from NIH 相似文献
67.
Jacqueline Jollés FranÇOise Schoentgen Pierre Jollès Ellen M. Prager Allan C. Wilson 《Journal of molecular evolution》1976,8(1):59-78
Summary The amino acid sequence of lysozyme c from chachalaca egg white was determined. Like other bird lysozymes c, that of the chachalaca has 129 amino acid residues. It differs from other avian lysozymes c by 27 to 31 amino acid substitutions as well as by being devoid of phenylalanine. It contains substitutions at 9 positions which are invariant in the other 7 bird lysozymes of known sequence. Although the chachalaca is classified zoologically in the order Galliformes, which includes chickens and other pheasant-like birds, its lysozyme differs more from those of pheasant-like birds than do the lysozymes c of ducks. Phylogenetic analysis of the sequence comparisons confirms that the lineage leading to chachalaca lysozyme c separated from that leading to other galliform lysozymes c before the duck lysozyme c lineage did. This indicates a contrast between protein evolution and evolution at the organismal level. Immunological comparison of chachalacalysozyme c with other lysozymes of known sequence provides further support for the proposal that immunological cross-reactivity is strongly dependent on degree of sequence resemblance among bird lysozymes.103rd communication on lysozymes from the Laboratory of P. Jollès. Supported in part by grants from C.N.R.S. (ER 102), I.N.S.E.R.M. (Groupe de recherche U-116), N.S.F. (GB-42028X), and N.I.H. (GM-21509). 相似文献
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Late-onset Alzheimer’s disease (LOAD) is known to have a complex, oligogenic etiology, with considerable genetic heterogeneity. We investigated the influence of genetic interactions between genes in the Alzheimer’s disease (AD) pathway on amyloid-beta (Aβ) deposition as measured by PiB or AV-45 ligand positron emission tomography (PET) to aid in understanding LOAD’s genetic etiology. Subsets of the Alzheimer’s Disease Neuroimaging Initiative (ADNI) cohorts were used for discovery and for two independent validation analyses. A significant interaction between RYR3 and CACNA1C was confirmed in all three of the independent ADNI datasets. Both genes encode calcium channels expressed in the brain. The results shown here support previous animal studies implicating interactions between these calcium channels in amyloidogenesis and suggest that the pathological cascade of this disease may be modified by interactions in the amyloid–calcium axis. Future work focusing on the mechanisms of such relationships may inform targets for clinical intervention. 相似文献
70.
* Actin organization and dynamics are essential for cell division, growth and cytoplasmic streaming. Here we analyse the effects of the overexpression of Actin Interacting Protein 1 (AIP1) on Arabidopsis development. * Arabidopsis plants were transformed with an ethanol-inducible AIP1 construct and the characteristics of these plants were analysed after induction. * When AIP1 was increased to approx. 90% above wild-type values, root hair development and actin organization in all cell types examined were disrupted. * Our data demonstrate that AIP1 is a key regulator of actin organization and that its regulation is essential for normal plant cell morphogenesis. 相似文献