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21.
H. J. T. Hoving M. R. Lipinski M. A. C. Roeleveld M. D. Durholtz 《Reviews in Fish Biology and Fisheries》2007,17(2-3):259-270
Lycoteuthis lorigera is an oceanic squid that is abundant in the Benguela system. Little is known about the biology of this squid except that
it is eaten in large numbers by numerous oceanic predators and that males grow to larger size than females, which is unique
for oegopsid squid. The aim of this study was to better understand the biology of this species by investigating its age and
growth, as well as its mating system. Toward this end, the age of 110 individuals, ranging from 35 to 110 mm, was estimated
by counting statolith growth increments. Estimates of age ranged from 131 to 315 days and varied with mantle length. No significant
differences were found in the size of males and females of equivalent ages. The relationship between ML and age for both sexes
was best described by an exponential growth curve, probably because no early life stages were aged in this study. Only one
mature male (ML 160 mm) was aged, and preliminary estimates suggest it was 386 days old. Instantaneous growth rates were low
(0.54% ML/day and 1.4% BM/day) but consistent with enoploteuthid growth rates. When the growth rate of L. lorigera was corrected for temperature encountered during the animal’s life, the growth rate was fast (0.47% BM/degree-days) and consistent
with the hypothesis that small cephalopods grow fast and that large cephalopods grow older, rather than fast. Mature females
were often mated and had spermatangia in a seminal receptacle on the dorsal pouch behind the nuchal cartilage. Males probably
transfer spermatangia to the females using their long second and/or third arm pair since the paired terminal organs open far
from the mantle opening.
M. A. C. Roeleveld deceased. 相似文献
22.
N. A. Moltschaniwskyj K. Hall Marek R. Lipinski J. E. A. R. Marian M. Nishiguchi M. Sakai D. J. Shulman B. Sinclair D. L. Sinn M. Staudinger R. Van Gelderen R. Villanueva K. Warnke 《Reviews in Fish Biology and Fisheries》2007,17(2-3):455-476
When using cephalopods as experimental animals, a number of factors, including morality, quality of information derived from
experiments, and public perception, drives the motivation to consider welfare issues. Refinement of methods and techniques
is a major step in ensuring protection of cephalopod welfare in both laboratory and field studies. To this end, existing literature
that provides details of methods used in the collection, handling, maintenance, and culture of a range of cephalopods is a
useful starting point when refining and justifying decisions about animal welfare. This review collates recent literature
in which authors have used cephalopods as experimental animals, revealing the extent of use and diversity of cephalopod species
and techniques. It also highlights several major issues when considering cephalopod welfare; how little is known about disease
in cephalopods and its relationship to senescence and also how to define objective endpoints when animals are stressed or
dying as a result of the experiment. 相似文献
23.
Bone remodeling occurs in an adult’s skeleton to adapt its architecture to external loadings. This involves bone resorption
by osteoclasts cells followed by formation of new bone by osteoblasts cells. During bone remodeling, osteoclasts and osteoblasts
interact with each other by expressing autocrine and paracrine factors that regulate cells’ population. Therefore, changes
in bone density depend on the amount of each acting cell population. The aim of this paper is to propose a model for the bone
remodeling process, which takes into account the opposite activity of both types of cells. For this purpose, a system of differential
equations, proposed by Komarova et al. (Bone 33:206–215, 2003), is introduced to describe bone cell interactions using parameters which characterize the autocrine and paracrine factors.
Such equations allow us to determine how the autocrine and paracrine factors vary in response to an external stimulus. It
is assumed that an equilibrium state can be obtained for values of stimulus near to some reference quantity. Far from this
value, unbalanced activity of osteoblasts and osteoclasts is observed, which leads to bone apposition or resorption. The proposed
model has been implemented into the finite element software ABAQUS to analyze the qualitative response of a bone structure
when subjected to certain mechanical loadings. Obtained results are satisfactory and in accordance with the expected bone
remodeling behavior. 相似文献
24.
25.
26.
JAMES A. NICHOLLS SONJA PREUSS ALEXANDER HAYWARD GEORGE MELIKA GYÖRGY CSÓKA JOSÉ‐LUIS NIEVES‐ALDREY RICHARD R. ASKEW MAJID TAVAKOLI KARSTEN SCHÖNROGGE GRAHAM N. STONE 《Molecular ecology》2010,19(3):592-609
Little is known about the evolutionary history of most complex multi‐trophic insect communities. Widespread species from different trophic levels might evolve in parallel, showing similar spatial patterns and either congruent temporal patterns (Contemporary Host‐tracking) or later divergence in higher trophic levels (Delayed Host‐tracking). Alternatively, host shifts by natural enemies among communities centred on different host resources could disrupt any common community phylogeographic pattern. We examined these alternative models using two Megastigmus parasitoid morphospecies associated with oak cynipid galls sampled throughout their Western Palaearctic distributions. Based on existing host cynipid data, a parallel evolution model predicts that eastern regions of the Western Palaearctic should contain ancestral populations with range expansions across Europe about 1.6 million years ago and deeper species‐level divergence at both 8–9 and 4–5 million years ago. Sequence data from mitochondrial cytochrome b and multiple nuclear genes showed similar phylogenetic patterns and revealed cryptic genetic species within both morphospecies, indicating greater diversity in these communities than previously thought. Phylogeographic divergence was apparent in most cryptic species between relatively stable, diverse, putatively ancestral populations in Asia Minor and the Middle East, and genetically depauperate, rapidly expanding populations in Europe, paralleling patterns in host gallwasp species. Mitochondrial and nuclear data also suggested that Europe may have been colonized multiple times from eastern source populations since the late Miocene. Temporal patterns of lineage divergence were congruent within and across trophic levels, supporting the Contemporary Host‐tracking Hypothesis for community evolution. 相似文献
27.
Lipinski CA 《Current opinion in chemical biology》2006,10(4):380-383
Intellectual property considerations decrease research productivity in subtle and unanticipated ways. Chemical probe exchange between Pharma and academia is hindered by academic IP interests. These are perceived as a subtle nuisance by the academic researcher. Novel ligands for oral targets are historically few and numbers of economically attractive oral drug targets are limited. Economically speculative targets lie in the academic domain but the medicinal chemistry to explore these in a drug discovery sense lies in Pharma and cooperation between the two is hindered by very different academic and Pharma views on chemical quality. Tools and probes for academic target validation can accommodate looser chemical quality criteria as opposed to the very strict chemical quality criteria required in Pharma drug discovery. 相似文献
28.
Lyons LA Bailey SJ Baysac KC Byrns G Erdman CA Fretwell N Froenicke L Gazlay KW Geary LA Grahn JC Grahn RA Karere GM Lipinski MJ Rah H Ruhe MT Bach LH 《Animal genetics》2006,37(4):383-386
The Tabby markings of the domestic cat are unique coat patterns for which no causative candidate gene has been inferred from other mammals. In this study, a genome scan was performed on a large pedigree of cats that segregated for Tabby coat markings, specifically for the Abyssinian (Ta-) and blotched (tbtb) phenotypes. There was linkage between the Tabby locus and eight markers on cat chromosome B1. The most significant linkage was between marker FCA700 and Tabby (Z = 7.56, theta = 0.03). Two additional markers in the region supported linkage, although not with significant LOD scores. Pairwise analysis of the markers supported the published genetic map of the cat, although additional meioses are required to refine the region. The linked markers cover a 17-cM region and flank an evolutionary breakpoint, suggesting that the Tabby gene has a homologue on either human chromosome 4 or 8. Alternatively, Tabby could be a unique locus in cats. 相似文献
29.
Lipinski KS Pelech S Mountain A Irvine AS Kraaij R Bangma CH Mills KH Todryk SM 《Cancer immunology, immunotherapy : CII》2006,55(3):347-354
Gene-directed enzyme-prodrug therapy (GDEPT) using nitroreductase (NTR), with efficient adenoviral delivery, and CB1954 (CB),
is an effective means of directly killing tumours. However, an immune-mediated bystander effect remains an important product
of GDEPT since it is often critical to the elimination of untransduced tumour cells both locally and at distal metastatic
sites through generation of tumour-specific immunity without the need for tumour antigen identification or the generation
of a personalised vaccine. The mode of induced tumour cell death is thought to contribute to the immunisation process, together
with the induction and release of stress proteins. Here, RM-9 murine prostate tumour cells were efficiently killed by adenovirally
delivered NTR/CB treatment both in vitro and in vivo, and bystander effects were observed. Cells appeared to die by pathways
that suggest necrosis more than that of classical apoptosis. NTR/CB-induced expression of a range of stress proteins was determined
by proteomic analysis, revealing chiefly heat shock protein (HSP)25 and HSP70 upregulation, whilst immune responses in vivo
were weak. In an attempt to enhance the anti-tumour effect, an adenoviral vector was constructed that co-expressed NTR and
HSP70, the latter being a known immune stimulator and chaperone of antigen. This combination elicited significantly enhanced
protection over NTR alone for both the treated tumour and a subsequent re-challenge. Protection was CD4+ and CD8+ T cell-dependent and was associated with tumour-specific CTL, IFNγ and IL-5 responses. The use of such a cytotoxic and immunomodulatory
gene combination in cancer therapy warrants further pursuit. 相似文献