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31.
Genetic evidence from Indian red jungle fowl corroborates multiple domestication of modern day chicken 总被引:1,自引:0,他引:1
Sriramana Kanginakudru Muralidhar Metta RD Jakati J Nagaraju 《BMC evolutionary biology》2008,8(1):174
Background
Domestication of chicken is believed to have occurred in Southeast Asia, especially in Indus valley. However, non-inclusion of Indian red jungle fowl (RJF), Gallus gallus murghi in previous studies has left a big gap in understanding the relationship of this major group of birds. In the present study, we addressed this issue by analyzing 76 Indian birds that included 56 G. g. murghi (RJF), 16 G. g. domesticus (domestic chicken) and 4 G. sonneratii (Grey JF) using both microsatellite markers and mitochondrial D-loop sequences. We also compared the D-loop sequences of Indian birds with those of 779 birds obtained from GenBank. 相似文献32.
Jonathan S. Towner Tara K. Sealy Marina L. Khristova César G. Albari?o Sean Conlan Serena A. Reeder Phenix-Lan Quan W. Ian Lipkin Robert Downing Jordan W. Tappero Samuel Okware Julius Lutwama Barnabas Bakamutumaho John Kayiwa James A. Comer Pierre E. Rollin Thomas G. Ksiazek Stuart T. Nichol 《PLoS pathogens》2008,4(11)
Over the past 30 years, Zaire and Sudan ebolaviruses have been responsible for large hemorrhagic fever (HF) outbreaks with case fatalities ranging from 53% to 90%, while a third species, Côte d''Ivoire ebolavirus, caused a single non-fatal HF case. In November 2007, HF cases were reported in Bundibugyo District, Western Uganda. Laboratory investigation of the initial 29 suspect-case blood specimens by classic methods (antigen capture, IgM and IgG ELISA) and a recently developed random-primed pyrosequencing approach quickly identified this to be an Ebola HF outbreak associated with a newly discovered ebolavirus species (Bundibugyo ebolavirus) distantly related to the Côte d''Ivoire ebolavirus found in western Africa. Due to the sequence divergence of this new virus relative to all previously recognized ebolaviruses, these findings have important implications for design of future diagnostic assays to monitor Ebola HF disease in humans and animals, and ongoing efforts to develop effective antivirals and vaccines. 相似文献
33.
Karen Olsson-Francis Rosa de la Torre Martin C. Towner Charles S. Cockell 《Origins of life and evolution of the biosphere》2009,39(6):565-579
Cyanobacteria are photosynthetic organisms that have been considered for space applications, such as oxygen production in
bioregenerative life support systems, and can be used as a model organism for understanding microbial survival in space. Akinetes
are resting-state cells of cyanobacteria that are produced by certain genera of heterocystous cyanobacteria to survive extreme
environmental conditions. Although they are similar in nature to endospores, there have been no investigations into the survival
of akinetes in extraterrestrial environments. The aim of this work was to examine the survival of akinetes from Anabaena cylindrica in simulated extraterrestrial conditions and in Low Earth Orbit (LEO). Akinetes were dried onto limestone rocks and sent
into LEO for 10 days on the ESA Biopan VI. In ground-based experiments, the rocks were exposed to periods of desiccation,
vacuum (0.7 × 10−3 kPa), temperature extremes (−80 to 80°C), Mars conditions (−27°C, 0.8 kPa, CO2) and UV radiation (325–400 nm). A proportion of the akinete population was able to survive a period of 10 days in LEO and
28 days in Mars simulated conditions, when the rocks were not subjected to UV radiation. Furthermore, the akinetes were able
to survive 28 days of exposure to desiccation and low temperature with high viability remaining. Yet long periods of vacuum
and high temperature were lethal to the akinetes. This work shows that akinetes are extreme-tolerating states of cyanobacteria
that have a practical use in space applications and yield new insight into the survival of microbial resting-state cells in
space conditions. 相似文献
34.
Sandra E. Gomez-Mejiba Zili Zhai Hammad Akram Leesa J. Deterding Kenneth Hensley Nataliya Smith Rheal A. Towner Kenneth B. Tomer Ronald P. Mason Dario C. Ramirez 《Free radical biology & medicine》2009,46(7):853-865
Biomolecule-centered radicals are intermediate species produced during both reversible (redox modulation) and irreversible (oxidative stress) oxidative modification of biomolecules. These oxidative processes must be studied in situ and in real time to understand the molecular mechanism of cell adaptation or death in response to changes in the extracellular environment. In this regard, we have developed and validated immuno-spin trapping to tag the redox process, tracing the oxidatively generated modification of biomolecules, in situ and in real time, by detecting protein- and DNA-centered radicals. The purpose of this methods article is to introduce and update the basic methods and applications of immuno-spin trapping for the study of redox biochemistry in oxidative stress and redox regulation. We describe in detail the production, detection, and location of protein and DNA radicals in biochemical systems, cells, and tissues, and in the whole animal as well, by using immuno-spin trapping with the nitrone spin trap 5,5-dimethyl-1-pyrroline N-oxide. 相似文献
35.
MAJBRITT OVERGÅRD SCHOU CASPER RISHOLT TORBEN L. LAURIDSEN MARTIN SØNDERGAARD PETER GRØNKJÆR LENE JACOBSEN SØREN BERG CHRISTIAN SKOV SANDRA BRUCET ERIK JEPPESEN 《Freshwater Biology》2009,54(7):1520-1531
1. Return of large‐bodied zooplankton populations is of key importance for creating a shift from a turbid to a clear‐water state in shallow lakes after a nutrient loading reduction. In temperate lakes, recovery is promoted by submerged macrophytes which function as a daytime refuge for large zooplankton. However, recovery of macrophytes is often delayed and use of artificial plant beds (APB) has been suggested as a tool to enhance zooplankton refuges, thereby reinforcing the shift to a clear‐water state and, eventually, colonisation of natural plants. 2. To further evaluate the potential of APB in lake restoration, we followed the day–night habitat choices of zooplankton throughout summer in a clear and a turbid lake. Observations were made in the pelagic and littoral zones and in APB in the littoral representing three different plant densities (coverage 0%, 40% and 80%). 3. In the clear lake, the zooplankton (primarily Daphnia) were mainly found in the pelagic area in spring, but from mid‐May they were particularly abundant in the APB and almost exclusively so in mid‐June and July, where they appeared in extremely high densities during day (up to 2600 ind. L−1). During night Daphnia densities were overall more equally distributed between the five habitats. Ceriodaphnia was proportionally more abundant in the APB during most of the season. Cyclopoids were more abundant in the high APB during day but were equally distributed between the five habitats during night. 4. In the turbid lake, however, no clear aggregation was observed in the APB for either of the pelagic genera (Daphnia and Bosmina). This may reflect a higher refuge effect in the open water due to the higher turbidity, reduced ability to orient to plant beds and a significantly higher fish density (mainly of roach, Rutilus rutilus, and perch, Perca fluviatilis) in the plant beds than in the clear lake. Chydorus was found in much higher proportions among the plants, while cyclopoids, particularly the pelagic Cyclops vicinus, dominated in the pelagic during day and in the pelagic and high density plants during night. 5. Our results suggest that water clarity is decisive for the habitat choice of large‐bodied zooplankton and that introduction of APB as a restoration measure to enhance zooplankton survival is only a useful tool when water clarity increases following loading reduction. Our results indicate that dense APB will be the most efficient. 相似文献
36.
Samuel D Vasikaran SA Paul Chubb Peter R Ebeling Nicole Jenkins Graham RD Jones Mark A Kotowicz Howard A Morris Hans-Gerhard Schneider Markus J Seibel Greg Ward 《The Clinical biochemist. Reviews / Australian Association of Clinical Biochemists》2014,35(4):237-242
Bone turnover markers (BTMs) are classified as either formation or resorption markers. Their concentrations in blood or urine of adults are considered to reflect the rate of bone remodelling and may be of use in the management of patients with bone disease. Major inter-method differences exist for BTMs, and harmonisation of methods is currently being pursued at an international level. Based on published data, this article describes age- and sex-specific Australian consensus reference intervals for adults for serum procollagen type I amino-terminal propeptide (s-PINP) and serum β-isomerised carboxy-terminal cross-linking telopeptide of type I collagen (s-CTX). 相似文献
37.
Graham RD Jones Sabrina DA Koetsier 《The Clinical biochemist. Reviews / Australian Association of Clinical Biochemists》2014,35(4):243-250
Reference intervals are commonly considered to allow for between-laboratory bias. The RCPAQAP Liquid Serum Chemistry Program has collected data on laboratory measurements as well as reference intervals. This allows assessment of the between-laboratory variation in results, reference intervals and the information transmitted by the combination of these factors. For the majority of common chemistry analytes, the between-laboratory variation in reference intervals is greater than the variation in results. Additionally the reference interval variation is generally not related to bias between the results. Use of common reference intervals, either as an average of the current intervals in use, or the intervals proposed by the AACB Harmonisation Group, improved the variation seen in the information produced by different laboratories. 相似文献
38.
Joseph W. Towner 《American journal of botany》1962,49(10):1064-1067
Towner , Joseph W. (U. California, Los Angeles.) Cytogenetics of Tagetes jaliscensis X T. erecta. Amer. Jour. Bot. 49(10): 1064–1067. Illus. 1962.—Although Tagetes jaliscensis and T. erecta are morphologically very distinct, the F1 hybrid between them had normal meiosis (12 bivalents) and was fertile. Segregation in F2 was undisturbed for marker genes on 4 pairs of chromosomes. These facts suggest that T. jaliscensis, like T. erecta, is an A-genome diploid (genome formula A2A2). From plant morphology, the A-subgenome of amphiploid T. patula is regarded as more likely derived from T. erecta than from T. jaliscensis. In T. jaliscensis X erecta F2, disk corolla anthocyanin (R = red) from T. jaliscensis segregated as a simple dominant over the absence of anthocyanin from T. erecta. A chlorophyll defect was determined by duplicate factor recessives. Tubular ray flowers (tu = tubular) segregated as a simple recessive to normal flat rays in the interspecific F2 and in T. erecta. 相似文献
39.
Three wheat samples collected in 1987 in Central Poland and naturally infected withFusarium spp were analyzed for the presence ofFusarium spp andFusarium toxins. Heads were separated into three fractions: kernels with visibleFusarium damage, healthy looking kernels, and chaff + rachis. The samples contained deoxynivalenol (2.0 – 40.0μg/g), nivalenol (O.O1μg/g), 4,7-dideoxynivalenol (0.10 – 0.15μg/g). 15-acetyldeoxynivalenol (0.10–2.00 μg/g), 3-acetyldeoxynivalenol (O/1Oμg/g), and zearalenone (0.01–2.00μg/g). This is the first report about 15 - acetyldeoxynivalenol in European wheat and the co-occurrence of 3 - acetyldeoxynivalenol and 15-acetyldeoxynivalenol in the same sample of contaminated cereals. 相似文献
40.
Effect of bacterial pyrogen on three lizard species 总被引:1,自引:0,他引:1
G M Hallman C E Ortega M C Towner A E Muchlinski 《Comparative biochemistry and physiology. A, Comparative physiology》1990,96(3):383-386
1. Three lizard species (Callopistes maculatus, Gerrhosaurus major, and Varanus exanthematicus) were tested for their response to intraperitoneal injection of alcohol-killed Aeromonas sobria. 2. A paired experimental design, in which each animal received an injection of sterile saline and 1 x 10(10) A. sobria, was utilized. 3. C. maculatus demonstrated a statistically significant increase in mean selected body temperature (MSBT) after bacteria injection. 4. G. major and V. exanthematicus did not demonstrate a statistically significant increase in MSBT. 5. C. maculatus is the first lizard species outside of the family Iguanidae to exhibit a febrile response to bacterial pyrogen. 相似文献