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111.
A point mutation G----A in exon 12 of the porphobilinogen deaminase gene results in exon skipping and is responsible for acute intermittent porphyria. 总被引:26,自引:2,他引:24
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B Grandchamp C Picat F de Rooij C Beaumont P Wilson J C Deybach Y Nordmann 《Nucleic acids research》1989,17(16):6637-6649
We have determined the mutation in a patient with acute intermittent porphyria. The mRNA coding for porphobilinogen deaminase was reverse transcribed then the cDNA was enzymatically amplified in vitro. Upon sequencing of a polymerase chain reaction product of abnormal size we found that this fragment lacked exon 12 of the gene. We analysed a genomic fragment containing exon 12 and determined that the patient was heterozygous for a point mutation G A at the last position of exon 12. We propose that this base change is responsible for an abnormal processing of the mutant allele such that exon 12 is missing in the mature mRNA. The resulting aberrant mRNA encodes a truncated protein which is inactive but stable and can be detected using antibodies directed against the normal enzyme. 相似文献
112.
Jane S. Sutcliffe Vahri Beaumont James M. Watson Chang Sing Chew Maria Beconi Daniel M. Hutcheson Celia Dominguez Ignacio Munoz-Sanjuan 《PloS one》2014,9(7)
Cyclic adenosine monophosphate (cAMP) signalling plays an important role in synaptic plasticity and information processing in the hippocampal and basal ganglia systems. The augmentation of cAMP signalling through the selective inhibition of phosphodiesterases represents a viable strategy to treat disorders associated with dysfunction of these circuits. The phosphodiesterase (PDE) type 4 inhibitor rolipram has shown significant pro-cognitive effects in neurological disease models, both in rodents and primates. However, competitive non-isoform selective PDE4 inhibitors have a low therapeutic index which has stalled their clinical development. Here, we demonstrate the pro-cognitive effects of selective negative allosteric modulators (NAMs) of PDE4D, D159687 and D159797 in female Cynomolgous macaques, in the object retrieval detour task. The efficacy displayed by these NAMs in a primate cognitive task which engages the corticostriatal circuitry, together with their suitable pharmacokinetic properties and safety profiles, suggests that clinical development of these allosteric modulators should be considered for the treatment of a variety of brain disorders associated with cognitive decline. 相似文献
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114.
M Beaumont D Batéjat C Piérard P Van Beers J B Denis O Coste P Doireau F Chauffard J French D Lagarde 《Journal of applied physiology》2004,96(1):50-58
We measured the effects of slow-release caffeine (SRC) and melatonin (Mlt) on sleep and daytime sleepiness after a seven-time zone eastbound flight. In a double-blind, randomized, placebo-controlled study, each of three groups of nine subjects was given either 300 mg SRC on recovery day 1 (D1) to D5 (0800) or 5 mg Mlt on preflight D-1 (1700), flight day D0 (1600), and from D1 to D3 (2300), or placebo (Pbo) at the same times. Nighttime sleep was evaluated by polysomnography and daytime sleepiness from measurements of sleep latencies and continuous wrist actigraphy. Compared with baseline, we found a significant rebound of slow-wave sleep on night 1 (N1) to N2 under Pbo and Mlt and a significant decrease in rapid eye movement sleep on N1 (Pbo) and N1-N3 (Mlt). Sleepiness was objectively increased under Pbo (D1-D6) and Mlt (D1-D3). SRC reduced sleepiness but also tended to affect sleep quality until the last drug day. In conclusion, both drugs have positive effects on some jet lag symptoms after an eastbound flight: SRC on daytime sleepiness, and Mlt on sleep. 相似文献
115.
L Lorenzelli-Edouard F Marie J L Beaumont 《Biomedicine / [publiée pour l'A.A.I.C.I.G.]》1980,33(5):160-163
In the antilipoprotein type of autoimmune hyperlipidemia (AIH), the immunoglobulins (Ig) are bound to lipoproteins by their antibody site and circulate as immune Ig-Lp complexes. In the earlier studies, the specific antibody activities were demonstrated in vitro by specific but rather sophisticated methods which were not suitable for the screening of antilipoprotein AIH in large populations. In the Ig-Lp test described here, the immunoglobulins bound to the low density lipoproteins (Ig-Lp) are detected by floating the complexes at D 1.10 in the ultracentrifuge in a physiological saline sucrose density gradient; delipidating them by ether in the presence of 0.2 M urea, and assaying the protein by radial immunodiffusion and laser immunonephelometry with antisera specific for IgG, IgA, IgM, low density lipoproteins and albumin. Radial immunodioffusion and immunonephelometry gave similar results. This Ig-Lp test was positive in 5 myelomas associated with hyperlipidemia, which were previously classified as AIH with specific methods. And the test was specific for the Ig type of the monoclonal antibody involved in each case (3 IgA, 1 IgG and 1 IgM). It was negative in 6 normolipidemic myelomas and also in 40 sera from healthy blood donors and one normal serum taken 4 hours after a fat meal. Although the Ig-Lp test is not specific for antilipoprotein antibodies, the results of this study allow to use if for the screening for AIH. 相似文献
116.
Rawson DJ Ballard S Barber C Barker L Beaumont K Bunnage M Cole S Corless M Denton S Ellis D Floc'h M Foster L Gosset J Holmwood F Lane C Leahy D Mathias J Maw G Million W Poinsard C Price J Russel R Street S Watson L 《Bioorganic & medicinal chemistry》2012,20(1):498-509
This paper describes our recent efforts to design and synthesise potent and selective PDE5 inhibitors and the use of in vitro predictors of clearance, absorption and permeability to maximise the potential for dose-proportional pharmacokinetics and good oral bioavailability in man. Optimisation of the preclinical profile resulted in the identification of UK-369003 (19a) and its nomination as a clinical candidate. The clinical pharmacokinetic and safety profile has enabled us to progress the compound to test its efficacy in patients with lower urinary tract symptoms (LUTS) associated with benign prostatic hyperplasia (BPH) and a paper describing its efficacy has recently been published. 相似文献
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118.
Linda J. Beaumont Rachael V. Gallagher Paul O. Downey Wilfried Thuiller Michelle R. Leishman Lesley Hughes 《Ecography》2009,32(5):757-764
Anthropogenically-induced climate change is one of the most important global threats to biodiversity. Understanding its impact on the distribution of exotic plant species is critical for developing effective adaptation and management strategies. However, there is insufficient information currently available on the biodiversity at risk from 1) exotic plant invasions, 2) climate change, and 3) the interaction between these two major threats, to develop such strategies. We use ecological niche models as a first step to identify zones inside and outside Australian protected areas that may be most at risk from invasions of three species of Hieracium (hawkweeds) under current and future (2030 and 2070) climate scenarios, should current control and eradication methods fail. These perennial herbs are native to Europe and invasive to New Zealand and North America. Naturalised in Australia, hawkweeds threaten native tussock grasslands and the grazing industry, and have been placed on the National Alert List. Using eight ecological niche models currently available in the software package BIOMOD, we found that these species have yet to realize the extent of their climatic distribution under present day climate in Australia. As climate change accelerates, the climatic range of hawkweeds was projected to contract overall. However, much of the Australian Alps, which contain large contiguous tracts of reserves and many endemic species, will continue to retain climatically suitable areas for hawkweeds through to 2070. These results emphasise the need for ongoing monitoring as well as focused control to minimize the likelihood of hawkweeds realizing their invasive potential in protected areas and beyond. 相似文献
119.
N. J. Beaumont 《Evolutionary biology》2009,36(2):256-266
The single-celled ancestors of multi-cellular animals (metazoans) did not need to transport nutrients between cells, but this ability is vital for modern animals. How could intercellular nutrient transport have begun? And how did this influence the early evolution of animals? In this hypothesis, I suggest that nutrients could have passed directly between the cytoplasm of conjoined cells in early compacted cell-balls, along the plane of the closed epithelium. This would have limited early animals to the size and form of modern embryos. The mechanisms that indirectly transport nutrients between discrete cells, via the extracellular fluid within the body-space, are modelled to have evolved sequentially; so comparison of nutrient transport processes could provide evidence of any early divergences of phyla. When the last of the indirect intercellular transport processes for essential nutrients had been developed, the extracellular fluid within the body-space would have contained all necessary nutrients. Then the epithelium could have greatly expanded, and cells lived and divided within the body-space. This development of nutrient transport processes would have enabled animals to greatly increase in size and complexity. 相似文献
120.
D. Lallias L. Gomez-Raya C. S. Haley I. Arzul S. Heurtebise A. R. Beaumont P. Boudry S. Lapègue 《Marine biotechnology (New York, N.Y.)》2009,11(5):570-584
We have identified quantitative trait loci (QTL) in the flat oyster (Ostrea edulis) for resistance to Bonamia ostreae, a parasite responsible for the dramatic reduction in the aquaculture of this species. An F2 family from a cross between a wild oyster and an individual from a family selected for resistance to bonamiosis was cultured
with wild oysters injected with the parasite, leading to 20% cumulative mortality. Selective genotyping of 92 out of a total
of 550 F2 progeny (i.e., 46 heavily infected oysters that died and 46 parasite-free oysters that survived) was performed using 20 microsatellites
and 34 amplification fragment length polymorphism primer pairs. Both a two-stage testing strategy and QTL interval mapping
methods were used. The two-stage detection strategy had a high power with a low rate of false positives and identified nine
and six probable markers linked to genes of resistance and susceptibility, respectively. Parent-specific genetic linkage maps
were built for the family, spanning ten linkage groups (n = 10) with an observed genome coverage of 69–84%. Three QTL were identified by interval mapping in the first parental map
and two in the second. Good concordance was observed between the results obtained after the two-stage testing strategy and
QTL mapping. 相似文献