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31.
Jung JA Jhang E. John Staba Jung Yun Kim 《In vitro cellular & developmental biology. Plant》1974,9(4):253-259
Summary Roots, stems, or leaves of American (Panax quinquefolium) and Korean (Panax ginsing) ginseng were grown as callus or supension tissue cultures. Tissue cultures ofP. ginseng would occasionally form plantlets. The fundamental chemical composition, inorganic analysis, and saponin (panaquilin) content
of American and Korean ginseng plants and tissue cultures were determined. The crude saponin content is very similar to, but
approximately one-half (1.3%, fresh weight) of that present in ginseng roots. Two-dimensional thin layer chromatographic analysis
revealed minor differences in the panaquilins present in American and Korean ginseng tissue cultures. The sapogenin, panaxadiol,
was isolated from Korean ginseng callus. 相似文献
32.
Impulsivity and poor executive control have been implicated in the pathogenesis of many developmental and neuropsychiatric disorders. Similarly, concussions/mild traumatic brain injuries (mTBI) have been associated with increased risk for neuropsychiatric disorders and the development of impulsivity and inattention. Researchers and epidemiologists have therefore considered whether or not concussions induce symptoms of attention-deficit/hyperactivity disorder (ADHD), or merely unmask impulsive tendencies that were already present. The purpose of this study was to determine if a single concussion in adolescence could induce ADHD-like impulsivity and impaired response inhibition, and subsequently determine if inherent impulsivity prior to a pediatric mTBI would exacerbate post-concussion symptomology with a specific emphasis on impulsive and inattentive behaviours. As these behaviours are believed to be associated with the frontostriatal circuit involving the nucleus accumbens (NAc) and the prefrontal cortex (PFC), the expression patterns of 8 genes (Comt, Drd2, Drd3, Drd4, Maoa, Sert, Tph1, and Tph2) from these two regions were examined. In addition, Golgi-Cox staining of medium spiny neurons in the NAc provided a neuroanatomical examination of mTBI-induced structural changes. The study found that a single early brain injury could induce impulsivity and impairments in response inhibition that were more pronounced in males. Interestingly, when animals with inherent impulsivity experienced mTBI, injury-related deficits were exacerbated in female animals. The single concussion increased dendritic branching, but reduced synaptic density in the NAc, and these changes were likely associated with the increase in impulsivity. Finally, mTBI-induced impulsivity was associated with modifications to gene expression that differed dramatically from the gene expression pattern associated with inherent impulsivity, despite very similar behavioural phenotypes. Our findings suggest the need to tailor treatment strategies for mTBI in light of an individual’s premorbid characteristics, given significant differences in molecular profiles of the frontostriatal circuits that depend upon sex and the etiology of the behavioural phenotype. 相似文献
33.
34.
D Tschoepe P Spangenberg J Esser B Schwippert B Kehrel P Roesen F A Gries 《Cytometry》1990,11(5):652-656
Occlusive vascular diseases are promoted by a "prethrombotic state" with increased platelet activity. Polymerization of cytoskeletal proteins and exposure of subcellular structures or rebinding of secreted proteins have been characterized as early reactions after platelet activation preceding adhesion and aggregation. Here, we demonstrate the kinetic increase in specific binding of monoclonal antibodies to thrombospondin (P10) and to platelet membrane activation markers CD63 (GP53, a 53 kD lysosomal protein) and CD62 (GMP140, a 140 kD alpha granule protein) by using a flow-cytometric bio-assay and the related change in the actin status by using the DNase-I inhibition assay after stimulation of normal human platelets with 0.2 U/ml thrombin. F-actin was raised from 41% to 51% of total platelet actin content 30 s after stimulation and remained thereafter constant (50% at 60 s). Simultaneously, the percentage of P10, CD63, and CD62 positive platelets was elevated from 5.4%, 24.4%, and 9.1% to 67.4%, 80.2%, and 82.3% respectively. The mean number of P10, CD63, and CD62 antibody binding sites increased from 3,300, 1,715, and 2,146 to 6,400, 6,800, and 9,016 per platelet. Conclusively, changes in the organization of the cytoskeletal protein "actin" and exposure of subcellular structures indicating platelet secretion can be regarded as markers of early platelet activation. Thus, the parallel response in both analytical systems provides further support for the diagnostic concept of flow-cytometric detection of preactivated platelets in the peripheral blood by using fluochrome staining procedures detecting activation dependent structural alterations directly at the cellular level. 相似文献
35.
36.
Simone Schehka Karl-Heinz Esser Elke Zimmermann 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2007,193(8):845-852
Empirical research on human and non-human primates suggests that communication sounds express the intensity of an emotional
state of a signaller. In the present study, we have examined communication sounds during induced social interactions of a
monogamous mammal, the tree shrew. To signal their unwillingness to mate, female tree shrews show defensive threat displays
towards unfamiliar males paralleled by acoustically variable squeaks. We assumed that the distance between interacting partners
as well as the behavior of the male towards the female indicates the intensity of perceived social threat and thereby the
arousal state of a female. To explore this hypothesis we analyzed dynamic changes in communication sounds uttered during induced
social interactions between a female and an unfamiliar male. Detailed videographic and sound analyzes revealed that the arousal
state predicted variations in communication sound structure reliably. Both, a decrease of distance and a male approaching
the female led to an increase in fundamental frequency and repetition rate of syllables. These findings support comparable
results in human and non-human primates and suggest that common coding rules in communication sounds govern acoustic conflict
regulation in mammals. 相似文献
37.
Schuldt K Kretz CC Timmann C Sievertsen J Ehmen C Esser C Loag W Ansong D Dering C Evans J Ziegler A May J Krammer PH Agbenyega T Horstmann RD 《PLoS genetics》2011,7(5):e1002066
Human genetics and immune responses are considered to critically influence the outcome of malaria infections including life-threatening syndromes caused by Plasmodium falciparum. An important role in immune regulation is assigned to the apoptosis-signaling cell surface receptor CD95 (Fas, APO-1), encoded by the gene FAS. Here, a candidate-gene association study including variant discovery at the FAS gene locus was carried out in a case-control group comprising 1,195 pediatric cases of severe falciparum malaria and 769 unaffected controls from a region highly endemic for malaria in Ghana, West Africa. We found the A allele of c.−436C>A (rs9658676) located in the promoter region of FAS to be significantly associated with protection from severe childhood malaria (odds ratio 0.71, 95% confidence interval 0.58–0.88, pempirical = 0.02) and confirmed this finding in a replication group of 1,412 additional severe malaria cases and 2,659 community controls from the same geographic area. The combined analysis resulted in an odds ratio of 0.71 (95% confidence interval 0.62–0.80, p = 1.8×10−7, n = 6035). The association applied to c.−436AA homozygotes (odds ratio 0.47, 95% confidence interval 0.36–0.60) and to a lesser extent to c.−436AC heterozygotes (odds ratio 0.73, 95% confidence interval 0.63–0.84), and also to all phenotypic subgroups studied, including severe malaria anemia, cerebral malaria, and other malaria complications. Quantitative FACS analyses assessing CD95 surface expression of peripheral blood mononuclear cells of naïve donors showed a significantly higher proportion of CD69+CD95+ cells among persons homozygous for the protective A allele compared to AC heterozygotes and CC homozygotes, indicating a functional role of the associated CD95 variant, possibly in supporting lymphocyte apoptosis. 相似文献
38.
Karl Esser 《Archives of microbiology》1963,46(2):217-226
Summary The ascomycete Podospora anserina forms two different phenoloxidases. According to their substrate specifity they can be classified as laccase and tyrosinase, respectively. While laccase is found in freshly prepared extracts in a highly active form, the tyrosinase needs to be activated by cold- or heat-treatment. Further characteristics of the two enzymes are: their different solubilities in ammoniumsulfate solution and their different heat inactivation rates. The half life times of partially purified extracts at 60° C are for laccase 2.5 min and for tyrosinase 23 min. 相似文献
39.
Karl Esser und Joseph Straub 《Molecular & general genetics : MGG》1956,87(4):625-626
Ohne Zusammenfassung 相似文献
40.
Karl Esser 《Molecular & general genetics : MGG》1956,87(4):595-624
Ohne ZusammenfassungMit 12 Textabbildungen 相似文献