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131.
S. EL‐SHOWK J. S. Van ZWEDEN P. D’ETTORRE L. SUNDSTRÖM 《Journal of evolutionary biology》2010,23(2):397-406
In social insects, workers trade personal reproduction for indirect fitness returns from helping their mother rear collateral kin. Colony membership is generally used as a proxy for kin discrimination, but the question remains whether recognition allows workers to discriminate between kin and nonkin regardless of colony affiliation. We investigated whether workers of the ant Formica fusca can identify their mother when fostered with their mother, their sisters, a hetero‐colonial queen or hetero‐colonial workers. We found that workers always displayed less aggression towards both their mother and their foster queen, as compared to an unfamiliar hetero‐colonial queen. In support of this finding, workers maintain their colony hydrocarbon profile regardless of foster regime, yet show modifications when exposed to different environments. This indicates that recognition entails environmental and genetic components, which allow both discrimination of kin in the absence of prior contact and learning of recognition cues based on group membership. 相似文献
132.
Open Access publishing is a valuable resource for the synthesis and distribution of essential health care information. This
article discusses the potential benefits of Open Access, specifically in terms of Low and Middle Income (LAMI) countries in
which there is currently a lack of informed health care providers - mainly a consequence of poor availability to information.
We propose that without copyright restrictions, Open Access facilitates distribution of the most relevant research and health
care information. Furthermore, we suggest that the technology and infrastructure that has been put in place for Open Access
could be used to publish download-able manuals, guides or basic handbooks created by healthcare providers in LAMI countries. 相似文献
133.
ABDERRAZAK EL ALAMI ELS VAN LAVIEREN ABOUFATIMA RACHIDA ABDERRAHMAN CHAIT 《American journal of primatology》2012,74(3):210-216
The Barbary macaque, Macaca sylvanus is a very adaptable primate species occupying a wide range of habitats in Morocco and Algeria. Several groups of this endangered macaque can be found in tourist sites, where they are affected by the presence of visitors providing food to them. We compare the activity budgets and the diet of semiprovisioned and wild‐feeding groups of Barbary macaques in the central High Atlas Mountains of Morocco from February to August 2008. We used instantaneous scan sampling at 15‐min intervals. The behaviors included in the activity budget were feeding, moving, foraging, resting, and aggressive display. Food items were grouped into seven categories. We found no differences between the two groups in the daily percentages of records attributed to feeding. The semiprovisioned group spent significantly more time engaged in resting and aggressive behavior, and foraged and moved significantly less than the wild‐feeding group. There was no significant difference between the two groups in time spent eating leaves, fruits, or roots and bark. The semiprovisioned group, however, spent significantly less time per day feeding on herbs, seeds, and acorns than the wild‐feeding group. Human food accounted for 26% of the daily feeding records for the semiprovisioned group and 1% for the wild‐feeding group. Our findings agree with previous studies and indicate that in the tourist site, where food is highly clumped, macaques decreased foraging time yet showed higher levels of contest competition. Our results support the common claim that the diet of the Barbary macaque is highly flexible, differing among its varied habitats. Conservation efforts for the Barbary macaques should take into account the changes in behavior that human‐modified environments may cause. 相似文献
134.
Tirsa L. E. van Westering Henrik J. Johansson Britt Hanson Anna M. L. Coenen-Stass Yulia Lomonosova Jun Tanihata Norio Motohashi Toshifumi Yokota Shin'ichi Takeda Janne Lehti Matthew J. A. Wood Samir EL Andaloussi Yoshitsugu Aoki Thomas C. Roberts 《Molecular & cellular proteomics : MCP》2020,19(12):2047-2068
Highlights
- •Proteomics analysis was performed in two murine models of Duchenne muscular dystrophy (mdx and mdx52) at three ages (8, 16 and 80 weeks) and compared with wild-type controls.
- •High-resolution isoelectric focusing liquid chromatography-tandem mass spectrometry enabled the quantification of 4974 proteins in all samples.
- •This study has revealed protein signatures of dystrophin deficiency and the progression of dystrophic pathology.
- •In contrast, the proteomes of the mdx and mdx52 mice were highly similar.
- •Pathway analysis revealed crosstalk between inflammatory, metabolic and muscle growth processes in dystrophic muscle.
135.
136.
Genetic footprints of late Quaternary climate change in the diversity of Patagonian‐Fueguian rodents
Species are impacted by climate change at both ecological and evolutionary time scales. Studies in northern continents have provided abundant evidence of dramatic shifts in distributions of species subsequent to the last glacial maximum (LGM), particularly at high latitudes. However, little is known about the history of southern continents, especially at high latitudes. South America is the only continent, other than Antarctica, that extends beyond 40 °S. Genetic studies of a few Patagonian species have provided seemingly conflicting results, indicating either postglacial colonization from restricted glacial refugia or persistence through glacial cycles and in situ differentiation. Using mitochondrial DNA sequences of 14 species of sigmodontine rodents, a major faunal ensemble of Patagonia and Tierra del Fuego, we show that at least nine of these species bear genetic footprints of demographic expansion from single restricted sources. However, timing of demographic expansion precedes the LGM in most of these species. Four species are fragmented phylogeographically within the region. Our results indicate that (i) demographic instability in response to historical climate change has been widespread in the Patagonian‐Fueguian region, and is generally more pronounced at high latitudes in both southern and northern continents; (ii) colonization from lower latitudes is an important component of current Patagonian‐Fueguian diversity; but (iii) in situ differentiation has also contributed to species diversity. 相似文献
137.
Intracellular phosphorylation of benzyladenosine is related to apoptosis induction in tobacco BY-2 cells 总被引:4,自引:1,他引:4
Treatment of tobacco BY‐2 cells with micromolar concentration of benzyladenosine ([9R]BA) resulted in the loss of cell viability in a time‐ and concentration‐dependent manner. Cell death induced by [9R]BA exhibited typical apoptotic hallmarks including cell shrinkage, chromatin condensation and degradation of nuclear DNA to characteristic high molecular weight (HMW) as well as nucleosomal size fragments. Externally added [9R]BA was very rapidly and almost quantitatively phosphorylated within BY‐2 cells. Accumulation of [9R]BA‐monophosphate was accompanied by massive production of endogenous reactive oxygen species (ROS), intracellular ATP depletion, and these events were followed by the loss of cell viability. Inhibition of intracellular phosphorylation of [9R]BA by adenosin kinase inhibitor, 5′‐amino‐5′‐deoxyadenosine (AdAs), diminished ROS production, ATP depletion, and consequently prevented cells from death. Selective inhibition of ROS production without restoring ATP production, however, did not provide any protection to cells. In contrast, even enhanced phosphorylation of [9R]BA caused by adenosine that simultaneously revived ATP synthesis reduced the number of dying cells. This is the first evidence of a direct relationship between intracellular phosphorylation of [9R]BA and apoptosis induction in BY‐2 cells. ATP depletion but not ROS production is the key secondary event that determines the cellular decision between life and death. 相似文献
138.
ANNA MARTINEZ EL MOUKHTAR ALIOUAT MURIEL POTTIER NAUSICÂA GANTOIS CLAIRE PINÇON ANNIE STANDAERT-VITSE EDUARDO DEI-CAS CÉCILE-MARIE ALIOUAT-DENIS 《The Journal of eukaryotic microbiology》2009,56(5):446-453
ABSTRACT. The separation of Pneumocystis carinii life-cycle stages while preserving infectivity is a hitherto unresolved challenge. We describe an original, reproducible, and efficient method for separating trophic from cystic forms of P. carinii using a high-speed cell sorter. The large amounts of highly purified (99.6±0.3%) infectious trophic and cystic forms can now be used to elucidate the poorly understood P. carinii life cycle. 相似文献
139.
Md. Parvez Anwar Md. Ariful Islam Khalid A. K. M. Mominul Islam Sabina Yeasmin Sharif Ahmed Adel Hadifa Ismail A. Ismail Akbar Hossain Ayman EL Sabagh 《Phyton》2021,90(5):1491-1506
Seed priming has proved to be an effective pre-germination seed invigoration technique for different crops to
improve seed and seedling performance under different abiotic stresses. In Bangladesh, winter rice is very often
exposed to cold waves just after sowing in the nursery bed resulting in poor seed germination and seedling emergence, yellowish and thin seedlings production, and a very low survival rate. Seed priming may mitigate the cold
stress during seed germination and seedling emergence and helps in the quality seedling production of winter rice.
To evaluate the efficacy of different seed priming techniques in increasing seedling emergence, growth, vigor and
survivability of winter rice cultivars under cold stress, a pot experiment was conducted at the Department of Agronomy, Bangladesh Agricultural University during December 2018 to January 2019. The experiment comprised
two factors, (A) Winter rice variety namely, i) BRRI dhan29 and ii) BRRI dhan36; (B) Seed priming agent namely
i) Control (no priming), ii) 20000 ppm NaCl, iii) 30000 ppm NaCl, iv) 20000 ppm KCl, v) 30000 ppm KCl, vi)
20000 ppm CaCl2, vii) 30000 ppm CaCl2, viii) 50 ppm CuSO4, ix) 75 ppm CuSO4, x) 10000 ppm ZnSO4, xi)
15000 ppm ZnSO4, xii) 2 ppm Na2MoO4, xiii) 3 ppm Na2MoO4, xiv) 100 ppm PEG (Polyethylene glycol
4000) and xv) 150 ppm PEG. Seeds were sown on two different dates viz., 1st December and 1st January so that
seedlings are exposed to cold stress at different stages. The experiment was laid out in a completely randomized
design (CRD) with three replications. Results indicated that (in most of the cases) seed priming has a positive
impact on seedling emergence rate (%), root length, shoot length, root shoot ratio, root dry weight, shoot dry
weight, seedling dry weight and survival rate (%). Among the priming agents, KCl and CaCl2 performed best;
while priming with NaCl and PEG showed no advantages over no priming for both the sowing dates. In general,
BRRI dhan36 performed better than BRRI dhan29 in terms of seedling growth because of its higher tolerance to
cold stress. But, both the varieties performed similarly in terms of emergence rate and survival rate. Thus, priming
is an effective tool to increase seed germination, better seedling growth, and higher seedling survivability of winter
rice under cold stress, and KCl (20000 ppm) or CaCl2 (20000 ppm) can be considered as a viable priming agent. 相似文献
140.
Comparative analysis of storage conditions and homogenization methods for tick and flea species for identification by MALDI‐TOF MS 下载免费PDF全文
A. NEBBAK B. EL HAMZAOUI J.‐M. BERENGER I. BITAM D. RAOULT L. ALMERAS P. PAROLA 《Medical and veterinary entomology》2017,31(4):438-448
Ticks and fleas are vectors for numerous human and animal pathogens. Controlling them, which is important in combating such diseases, requires accurate identification, to distinguish between vector and non‐vector species. Recently, matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOF‐MS) was applied to the rapid identification of arthropods. The growth of this promising tool, however, requires guidelines to be established. To this end, standardization protocols were applied to species of Rhipicephalus sanguineus (Ixodida: Ixodidae) Latreille and Ctenocephalides felis felis (Siphonaptera: Pulicidae) Bouché, including the automation of sample homogenization using two homogenizer devices, and varied sample preservation modes for a period of 1–6 months. The MS spectra were then compared with those obtained from manual pestle grinding, the standard homogenization method. Both automated methods generated intense, reproducible MS spectra from fresh specimens. Frozen storage methods appeared to represent the best preservation mode, for up to 6 months, while storage in ethanol is also possible, with some caveats for tick specimens. Carnoy's buffer, however, was shown to be less compatible with MS analysis for the purpose of identifying ticks or fleas. These standard protocols for MALDI‐TOF MS arthropod identification should be complemented by additional MS spectrum quality controls, to generalize their use in monitoring arthropods of medical interest. 相似文献