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71.
If a diagnosis of traumatic pancreatitis is made and the patient does not improve clinically during the first 24 hours, transection of the pancreas should be suspected. If this is found to be the case at operation, the distal pancreas should be resected and the proximal end of the pancreas closed carefully with interrupted mattress suture of non-absorbable suture material. Particularly, the pancreatic duct should be ligated to prevent the formation of an external fistula. Any attempt at reapproximation of the transected pancreas will invariably result in an external pancreatic fistula if the patient survives the immediate postoperative period. 相似文献
72.
Successive freezing and thawing of whole blood results in a consistently higher yield of various prostaglandin (PG) compounds. Evaluations were made with radioimmunological assay. The increase in PG concentrations seems to be more associated with cell fragmentation and not with the dissociation of albumin-PG complex. Our data suggest that there may be some dissociation of non-albumin-PG complexes. Artifactually high PG concentrations due to in vitro PG synthetase activity appears minimal at least with respect to indomethacin blocking of this enzyme. There are, in general, only slight differences in PG concentrations in samples with and without indomethacin. 相似文献
73.
74.
Though pelvic infection in women fitted with an intrauterine device (I.U.C.D.) is reported to be rare, three cases, gonococcal in origin, are presented. These case histories suggest that the presence of an I.U.C.D. increases the severity of gonorrhoea, while removal of the device before antibiotic therapy is probably essential for proper management. The literature and our experience suggest that where pelvic infection and an I.U.C.D. coexist gonorrhoea should be considered a likely diagnosis. 相似文献
75.
76.
C. R. Morton N. J. Rzechorzek J. D. Maman M. Kuramochi H. Sekiguchi R. Rambo Y. C. Sasaki O. R. Davies L. Pellegrini 《Open biology》2021,11(6)
The DNA repair factor CtIP has a critical function in double-strand break (DSB) repair by homologous recombination, promoting the assembly of the repair apparatus at DNA ends and participating in DNA-end resection. However, the molecular mechanisms of CtIP function in DSB repair remain unclear. Here, we present an atomic model for the three-dimensional architecture of human CtIP, derived from a multi-disciplinary approach that includes X-ray crystallography, small-angle X-ray scattering (SAXS) and diffracted X-ray tracking (DXT). Our data show that CtIP adopts an extended dimer-of-dimers structure, in agreement with a role in bridging distant sites on chromosomal DNA during the recombinational repair. The zinc-binding motif in the CtIP N-terminus alters dynamically the coiled-coil structure, with functional implications for the long-range interactions of CtIP with DNA. Our results provide a structural basis for the three-dimensional arrangement of chains in the CtIP tetramer, a key aspect of CtIP function in DNA DSB repair. 相似文献
77.
Emily Sekula-Wood Claudia Benitez-Nelson Steve Morton Clarissa Anderson Christopher Burrell Robert Thunell 《Harmful algae》2011,10(6):567-575
Blooms of domoic acid (DA) producing Pseudo-nitzschia, regularly occur off the coast of California. Although it has been hypothesized that these blooms are increasing in frequency, the lack of historical records limits our understanding of potential causal mechanisms. In this study, an 15-year time-series (1993–2008) of sediment trap samples collected from the Santa Barbara Basin (SBB) at 540 m were analyzed for Pseudo-nitzschia (n = 196, microscopy and SEM) and DA (n = 206, LC–MS/MS) concentrations and fluxes. Results suggest that there was an abrupt shift towards greater frequency and higher magnitude Pseudo-nitzschia blooms and toxic DA flux events in the SBB after the year 2000. SEM analysis of sediment trap material indicates that these events were mainly blooms of P. australis, with cell fluxes increasing by an order of magnitude from a maximum of 4.5 × 106 cells m−2 d−1 pre-2000, to as high as 3.2 × 108 cells m−2 d−1 thereafter. Similarly, sediment trap DA fluxes increased by an average of 13.4 μg m−2 d−1, with only one large event (>5 μg m−2 d−1) from 1993 to 1999 versus 16 large DA events from 2000 to 2008. While the causes of this abrupt shift remain ambiguous, we suggest that this shift may be related to natural climate variability associated with a change in phase of the North Pacific Gyre Oscillation (NPGO) and its potential influence on the composition and magnitude of waters that are upwelled into the SBB. 相似文献
78.
Debajit Saha David Morton Michael Ariel Ralf Wessel 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2011,197(2):153-165
The optic tectum holds a central position in the tectofugal pathway of non-mammalian species and is reciprocally connected
with the nucleus isthmi. Here, we recorded from individual nucleus isthmi pars parvocellularis (Ipc) neurons in the turtle
eye-attached whole-brain preparation in response to a range of computer-generated visual stimuli. Ipc neurons responded to
a variety of moving or flashing stimuli as long as those stimuli were small. When mapped with a moving spot, the excitatory
receptive field was of circular Gaussian shape with an average half-width of less than 3°. We found no evidence for directional
sensitivity. For moving spots of varying sizes, the measured Ipc response-size profile was reproduced by the linear Difference-of-Gaussian
model, which is consistent with the superposition of a narrow excitatory center and an inhibitory surround. Intracellular
Ipc recordings revealed a strong inhibitory connection from the nucleus isthmi pars magnocellularis (Imc), which has the anatomical
feature to provide a broad inhibitory projection. The recorded Ipc response properties, together with the modulatory role
of the Ipc in tectal visual processing, suggest that the columns of Ipc axon terminals in turtle optic tectum bias tectal
visual responses to small dark changing features in visual scenes. 相似文献
79.
James D. Nichols Mark D. Koneff Patricia J. Heglund Melinda G. Knutson Mark E. Seamans James E. Lyons John M. Morton Malcolm T. Jones G. Scott Boomer Byron K. Williams 《The Journal of wildlife management》2011,75(1):6-18
Climate change and its associated uncertainties are of concern to natural resource managers. Although aspects of climate change may be novel (e.g., system change and nonstationarity), natural resource managers have long dealt with uncertainties and have developed corresponding approaches to decision-making. Adaptive resource management is an application of structured decision-making for recurrent decision problems with uncertainty, focusing on management objectives, and the reduction of uncertainty over time. We identified 4 types of uncertainty that characterize problems in natural resource management. We examined ways in which climate change is expected to exacerbate these uncertainties, as well as potential approaches to dealing with them. As a case study, we examined North American waterfowl harvest management and considered problems anticipated to result from climate change and potential solutions. Despite challenges expected to accompany the use of adaptive resource management to address problems associated with climate change, we conclude that adaptive resource management approaches will be the methods of choice for managers trying to deal with the uncertainties of climate change. © 2010 The Wildlife Society. 相似文献
80.
Robert L. Pitman John W. Durban Michael Greenfelder Christophe Guinet Morton Jorgensen Paula A. Olson Jordi Plana Paul Tixier Jared R. Towers 《Polar Biology》2011,34(2):303-306
Studies have shown that killer whale (Orcinus orca) communities in high latitudes regularly comprise assemblages of sympatric ‘ecotypes’—forms that differ in morphology, behavior,
and prey preferences. Although they can appear superficially similar, recent genetic evidence suggests that breeding is assortative
among ecotypes within individual communities, and species-level divergences are inferred in some cases. Here, we provide information
on a recently recognized ‘type D’ killer whale based on photographs of a 1955 mass stranding in New Zealand and our own six
at-sea sightings since 2004. It is the most distinctive-looking form of killer whale that we know of, immediately recognizable
by its extremely small white eye patch. Its geographic range appears to be circumglobal in subantarctic waters between latitudes
40°S and 60°S. School sizes are relatively large (mean 17.6; range 9–35; n = 7), and although nothing is known about the type D diet, it is suspected to include fish because groups have been photographed
around longline vessels where they reportedly depredate Patagonian toothfish (Dissostichus eleginoides). 相似文献