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排序方式: 共有161条查询结果,搜索用时 0 毫秒
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Nathan Raw 《BMJ (Clinical research ed.)》1915,2(2856):468-469
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Simon R. Wotton Stephen Bladwell Wendy Mattingley Neil G. Morris David Raw Marc Ruddock 《Bird Study》2018,65(2):145-160
Capsule: The fifth UK and the Isle of Man survey of Hen Harrier in 2016 showed varying trends by country and region.Aim: To estimate the size of the breeding Hen Harrier population (with associated 95% confidence intervals) in the UK and Isle of Man, constituent countries and Scottish regions, in 2016 and calculate population change over the five surveys to date.Methods: Complete surveys were made of all 10-km squares likely to be occupied by breeding Hen Harriers in England, Wales, Northern Ireland and the Isle of Man, using standard methods developed for previous national surveys. In Scotland, self-selected 10-km squares were surveyed by volunteers and a stratified random selection of the remaining 10-km squares within the known breeding range was surveyed.Results: The UK and Isle of Man Hen Harrier population was estimated at 575 territorial pairs (95% confidence limits, 477–694), a non-significant decline of 13% since 2010 but a significant decline of 24% since 2004. Scotland held the majority (80%) of the population with 460 (359–573) territorial pairs. Elsewhere, 46 territorial pairs were recorded in Northern Ireland, 35 in Wales, 30 in the Isle of Man and four in England. Significant decreases were recorded in the number of pairs in Scotland using grouse moor (?57%) and young forest (?54%).Conclusion: The combined breeding population of Hen Harriers in the UK and Isle of Man has shown a non-significant decline between 2010 and 2016. There were notable decreases in England, Northern Ireland and Wales since 2010. 相似文献
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Anatomical and phenological implications of the relationship between Schinus polygama (Cav.) (Cabrera) and the galling insect Calophya rubra (Blanchard) 下载免费PDF全文
L. M. Guedes N. Aguilera B. G. Ferreira J. Becerra V. Hernández R. M. S. Isaias 《Plant biology (Stuttgart, Germany)》2018,20(3):507-515
- The success of galling insects could be determined by synchronisation with host plant phenology and climate conditions, ensuring suitable oviposition sites for gall induction and food resources for their survival. The anatomical, histochemical and phenological synchronisation strategies between Calophya rubra (Blanchard) (Hemiptera: Psylloidea) and its host, the evergreen plant Schinus polygama (Cav.) (Cabrera) (Anacardiaceae), in the Mediterranean climate of southern Chile was evaluated and compared to that of the congeneric C. cf. duvauae (Scott) from Brazil and closely related host plant S. engleri in a subtropical climate.
- Anatomical, histometric, histochemical and vegetative phenology studies of the stem and galls were conducted from June 2015 to December 2016.
- Based on the anatomical, histometric and histochemical analysis, the conical stem gall traits imply gains over the non‐galled stem toward the galling insect survival, but the maintenance of phellem, secretory ducts and pith indicate conservative developmental traits that cannot be manipulated by C. rubra. Our results indicate that the conditions of the Mediterranean climate zone limit C. rubra immature activity during unfavourable periods, probably determining a diapause period and a univoltine life cycle, which are peculiarities of the S. polygama– C. rubra system.
- The synchronisation between development and seasonality confers peculiarities to the S. polygama– C. rubra system in the Mediterranean climate zone.
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The acyclic CB1R inverse agonist taranabant mediates weight loss by increasing energy expenditure and decreasing caloric intake 总被引:6,自引:0,他引:6
Addy C Wright H Van Laere K Gantz I Erondu N Musser BJ Lu K Yuan J Sanabria-Bohórquez SM Stoch A Stevens C Fong TM De Lepeleire I Cilissen C Cote J Rosko K Gendrano IN Nguyen AM Gumbiner B Rothenberg P de Hoon J Bormans G Depré M Eng WS Ravussin E Klein S Blundell J Herman GA Burns HD Hargreaves RJ Wagner J Gottesdiener K Amatruda JM Heymsfield SB 《Cell metabolism》2008,7(1):68-78
Cannabinoid 1 receptor (CB1R) inverse agonists are emerging as a potential obesity therapy. However, the physiological mechanisms by which these agents modulate human energy balance are incompletely elucidated. Here, we describe a comprehensive clinical research study of taranabant, a structurally novel acyclic CB1R inverse agonist. Positron emission tomography imaging using the selective CB1R tracer [(18)F]MK-9470 confirmed central nervous system receptor occupancy levels ( approximately 10%-40%) associated with energy balance/weight-loss effects in animals. In a 12-week weight-loss study, taranabant induced statistically significant weight loss compared to placebo in obese subjects over the entire range of evaluated doses (0.5, 2, 4, and 6 mg once per day) (p < 0.001). Taranabant treatment was associated with dose-related increased incidence of clinical adverse events, including mild to moderate gastrointestinal and psychiatric effects. Mechanism-of-action studies suggest that engagement of the CB1R by taranabant leads to weight loss by reducing food intake and increasing energy expenditure and fat oxidation. 相似文献
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Ioannis Ugo Isaias Mariangela Dipaola Marlies Michi Alberto Marzegan Jens Volkmann Marina L. Rodocanachi Roidi Carlo Albino Frigo Paolo Cavallari 《PloS one》2014,9(4)
Rett syndrome is an X-linked neurodevelopmental condition mainly characterized by loss of spoken language and a regression of purposeful hand use, with the development of distinctive hand stereotypies, and gait abnormalities. Gait initiation is the transition from quiet stance to steady-state condition of walking. The associated motor program seems to be centrally mediated and includes preparatory adjustments prior to any apparent voluntary movement of the lower limbs. Anticipatory postural adjustments contribute to postural stability and to create the propulsive forces necessary to reach steady-state gait at a predefined velocity and may be indicative of the effectiveness of the feedforward control of gait. In this study, we examined anticipatory postural adjustments associated with gait initiation in eleven girls with Rett syndrome and ten healthy subjects. Muscle activity (tibialis anterior and soleus muscles), ground reaction forces and body kinematic were recorded. Children with Rett syndrome showed a distinctive impairment in temporal organization of all phases of the anticipatory postural adjustments. The lack of appropriate temporal scaling resulted in a diminished impulse to move forward, documented by an impairment in several parameters describing the efficiency of gait start: length and velocity of the first step, magnitude and orientation of centre of pressure-centre of mass vector at the instant of (swing-)toe off. These findings were related to an abnormal muscular activation pattern mainly characterized by a disruption of the synergistic activity of antagonistic pairs of postural muscles. This study showed that girls with Rett syndrome lack accurate tuning of feedforward control of gait. 相似文献
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Neves FO Ho PL Raw I Pereira CA Moreira C Nascimento AL 《Protein expression and purification》2004,35(2):353-359
Interferons (IFNs) represent an important defense mechanism in vertebrates. In this work, we describe gene synthesis and assembly using the polymerase chain reaction as a method for single-step synthesis of DNA sequences. The oligonucleotides designed were based on Escherichia coli codon usage and two genes of IFN were synthesized: one containing a DNA sequence already known and the other, a mutated form in which two cysteine amino acid residues were replaced by serines in an attempt to improve the stability of the protein. DNA sequences were cloned into pAE, an E. coli vector that allows heterologous protein expression with or without a histidine tag. Recombinant human interferons (rhIFNs) were identified by Western blotting and ELISA using anti-human interferon polyclonal antibodies. Purification of the recombinant His-tagged proteins was achieved in a single step by Ni(2+)-charged column chromatography while proteins without His-tag were purified by extensively washing the inclusion bodies, the final yields being approximately 210 and 75mg/L, respectively. The rhIFNs expressed within this system were biologically active ( approximately 1,1x10(8)IU/mg) based on antiviral assay. The combined methodologies described here proved to be cost-effective and could be extended to other genes/proteins of interest. 相似文献
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