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51.
52.
Ooms G. Karp A. Roberts J. 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1983,64(2):169-175
Theoretical and Applied Genetics - Agrobacterium tumefaciens strains, known to induce tobacco crown galls that spontaneously develop shoots, were used to induce galls on cultured shoots of a... 相似文献
53.
J. F. Antoniw G. Ooms R. F. White G. J. Wullems L. v. Vloten-Doting 《Plant molecular biology》1983,2(6):317-320
Large amounts of pathogenesis-related (PR) proteins were found inNicotiana tabacum crown gall tissue, following transformation of normal tobacco cells withAgrobacterium tumefaciens. In contrast, PR proteins were not detected in leaves of grafted plants that had been recovered from crown gall tissue even though these plants were still transformed as shown by their inability to form roots and ability to produce octopine. No difference was observed in susceptibility to virus infection between untransformed and transformed plants grafted onto identical rootstocks. The results are discussed in relation to physiological factors controlling PR protein induction and virus resistance. 相似文献
54.
Whole body content of androgen (testosterone + 5 alpha-dihydrotestosterone) was invariably higher in male than in female rat pups killed 1 or 3 h after natural delivery, whereas androgen content was equivalent in males and females killed immediately or 6, 12, and 24 h after birth. Testicular content of androgen was significantly elevated in males killed 1 and 24 h after birth, compared with levels in males killed immediately, or 3, 6, and 12 h after birth. Thus, heightened testicular androgen content was only initially associated with increased systemic levels of androgen in males during the immediate postpartum period. A second study assessed the possibility that the body's clearance (i.e., metabolism plus excretion) of testosterone is lower in newborn rats upon separation from the placental circulation than in slightly older pups. Rats of both sexes killed 1 and 3 h after s.c. injection of [3H] testosterone had significantly higher plasma concentrations of [3H] testosterone as well as several 5 alpha-reduced androgens (5 alpha-dihydrotestosterone, 3 alpha-androstanediol, and androsterone) when injections were given within minutes as opposed to 24 h after birth. This suggests that in both sexes the clearance of testosterone is slower immediately after birth than at later ages. This phenomenon together with a brief postnatal elevation in the testicular synthesis and secretion of testosterone may explain the temporary rise in circulating androgen concentrations that occurs in the newborn male rat. 相似文献
55.
The flash-induced P515 absorbance change in intact chloroplasts consists of a fast and a slow phase. There is disagreement in the literature over the origin of the slow phase. Here we argue that the flash-induced slow phase in P515 absorbance change is composed of two different components. One component is most probably due to the electrogenic Q-cycle associated with the cytochrome b/f complex. The second component has decay kinetics that are much slower than the electrogenic reactions. We suggest that the second component is due to a non-electrogenic reaction.Abbreviations CCCP
carbonyl cyanide m-chlorophenylhydrazone
- DBMIB
2,5-dibromo-3-methyl-6-isopropyl-p-benzoquinone
- DCCD
dicyclohexylcarbodiimide
- DQH2
durohydroquinone
- MV
methylviologen
- P515
Absorbance change at 518 nm 相似文献
56.
M. J. A. G. De Ronde-Tillmans R. M. Nuis J. A. Goudzwaard P. A. Cummins T. W. Hokken M. P. H. Van Wiechen J. F. W. Ooms J. Daemen N. M. D. A. Van Mieghem F. U. S. Mattace-Raso M. J. Lenzen P. P. T. de Jaegere 《Netherlands heart journal》2022,30(9):411
IntroductionTranscatheter aortic valve implantation (TAVI) has matured to the treatment of choice for most patients with aortic stenosis (AS). We sought to identify trends in patient and procedural characteristics, and clinical outcomes in all patients who underwent TAVI between 2005 and 2020.MethodsA single-centre analysis was performed on 1500 consecutive patients who underwent TAVI, divided into three tertiles (T) of 500 patients treated between November 2005 and December 2014 (T1), January 2015 and May 2018 (T2) and June 2018 and April 2020 (T3).ResultsOver time, mean age and gender did not change (T1 to T3: 80, 80 and 79 years and 53%, 55% and 52% men, respectively), while the Society of Thoracic Surgeons risk score declined (T1: 4.5% to T3: 2.7%, p < 0.001). Use of general anaesthesia also declined over time (100%, 24% and 1% from T1 to T3) and transfemoral TAVI remained the default approach (87%, 94% and 92%). Median procedure time and contrast volume decreased significantly (186, 114 and 56 min and 120, 100 and 80 ml, respectively). Thirty-day mortality (7%, 4% and 2%), stroke (7%, 3% and 3%), need for a pacemaker (19%, 22% and 8%) and delirium (17%, 12% and 8%) improved significantly, while major bleeding/vascular complications did not change (both approximately 9%, 6% and 6%). One-year survival was 80%, 88% and 92%, respectively.ConclusionOver our 15 years’ experience, patient age remained unchanged but the patient risk profile became more favourable. Simplification of the TAVI procedure occurred in parallel with major improvement in outcomes and survival. Bleeding/vascular complications and the need for pacemaker implantation remain the Achilles’ heel of TAVI.Supplementary InformationThe online version of this article (10.1007/s12471-022-01662-2) contains supplementary material, which is available to authorized users. 相似文献
57.
Phosphoinositide signals regulate cell proliferation, differentiation, cytoskeletal rearrangement and intracellular trafficking. Hydrolysis of PtdIns(4,5)P2 and PtdIns(3,4,5)P3, by inositol polyphosphate 5-phosphatases regulates synaptic vesicle recycling (synaptojanin-1), hematopoietic cell function [SHIP1(SH2-containing inositol polyphosphate 5-phosphatase-1)], renal cell function [OCRL (oculocerebrorenal syndrome of Lowe)] and insulin signalling (SHIP2). We present here a detailed review of the characteristics of the ten mammalian 5-phosphatases. Knockout mouse phenotypes and underexpression studies are associated with significant phenotypic changes, indicating non-redundant roles, despite, in many cases, overlapping substrate specificity and tissue expression. The extraordinary complexity in the control of phosphoinositide signalling continues to be revealed. 相似文献
58.
Sea urchin Hox genes: insights into the ancestral Hox cluster 总被引:3,自引:0,他引:3
We describe the Hox cluster in the radially symmetric sea urchin and
compare our findings to what is known from clusters in bilaterally
symmetric animals. Several Hox genes from the direct-developing sea urchin
Heliocidaris erythrogramma are described. CHEF gel analysis shows that the
Hox genes are clustered on a < or = 300 kilobase (kb) fragment of DNA,
and only a single cluster is present, as in lower chordates and other
nonvertebrate metazoans. Phylogenetic analyses of sea urchin, amphioxus,
Drosophila, and selected vertebrate Hox genes confirm that the H.
erythrogramma genes, and others previously cloned from other sea urchins,
belong to anterior, central, and posterior groups. Despite their radial
body plan and lack of cephalization, echinoderms retain at least one of the
anterior group Hox genes, an orthologue of Hox3. The structure of the
echinoderm Hox cluster suggests that the ancestral deuterostome had a Hox
cluster more similar to the current chordate cluster than was expected Sea
urchins have at least three Abd-B type genes, suggesting that Abd-B
expansion began before the radiation of deuterostomes.
相似文献
59.
Myocarditis is indicated as the second leading cause of sudden death in young adults. Reovirus induces myocarditis in neonatal mice, providing a tractable model system for investigation of this important disease. Alpha/beta-interferon (IFN-α/β) treatment improves cardiac function and inhibits viral replication in patients with chronic myocarditis, and the host IFN-α/β response is a determinant of reovirus strain-specific differences in induction of myocarditis. Virus-induced IFN-β stimulates a signaling cascade that establishes an antiviral state and further induces IFN-α/β through an amplification loop. Reovirus strain-specific differences in induction of and sensitivity to IFN-α/β are associated with the viral M1, L2, and S2 genes. The reovirus M1 gene-encoded μ2 protein is a strain-specific repressor of IFN-β signaling, providing one possible mechanism for the variation in resistance to IFN and induction of myocarditis between different reovirus strains. We report here that μ2 amino acid 208 determines repression of IFN-β signaling and modulates reovirus induction of IFN-β in cardiac myocytes. Moreover, μ2 amino acid 208 determines reovirus replication, both in initially infected cardiac myocytes and after viral spread, by regulating the IFN-β response. Amino acid 208 of μ2 also influences the cytopathic effect in cardiac myocytes after spread. Finally, μ2 amino acid 208 modulates myocarditis in neonatal mice. Thus, repression of IFN-β signaling mediated by reovirus μ2 amino acid 208 is a determinant of the IFN-β response, viral replication and damage in cardiac myocytes, and myocarditis. These results demonstrate that a single amino acid difference between viruses can dictate virus strain-specific differences in suppression of the host IFN-β response and, consequently, damage to the heart. 相似文献
60.
The APOBEC3 family comprises seven cytidine deaminases (APOBEC3A [A3A] to A3H), which are expressed to various degrees in HIV-1 susceptible cells. The HIV-1 Vif protein counteracts APOBEC3 restriction by mediating its degradation by the proteasome. We hypothesized that Vif proteins from various HIV-1 subtypes differ in their abilities to counteract different APOBEC3 proteins. Seventeen Vif alleles from seven HIV-1 subtypes were tested for their abilities to degrade and counteract A3G, A3F, and A3H haplotype II (hapII). We show that most Vif alleles neutralize A3G and A3F efficiently but display differences with respect to the inhibition of A3H hapII. The majority of non-subtype B Vif alleles tested presented some activity against A3H hapII, with two subtype F Vif variants being highly effective in counteracting A3H hapII. The residues required for activity were mapped to two residues in the amino-terminal region of Vif (positions 39F and 48H). Coimmunoprecipitations showed that these two amino acids were necessary for association of Vif with A3H hapII. These findings suggest that the A3H hapII binding site in Vif is distinct from the regions important for A3G and A3F recognition and that it requires specific amino acids at positions 39 and 48. The differential Vif activity spectra, especially against A3H hapII, suggest adaptation to APOBEC3 repertoires representative of different human ancestries. Phenotypic assessment of anti-APOBEC3 activity of Vif variants against several cytidine deaminases will help reveal the requirement for successful replication in vivo and ultimately point to interventions targeting the Vif-APOBEC3 interface. 相似文献