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81.
Hundreds of thousands of juvenile yellow tang, Zebrasoma flavescens, are caught each year in the state of Hawai’i (USA) for the live aquarium trade. As part of an extensive adaptive management
strategy built around a network of protected areas, an emphasis was placed on understanding this important species’ life history.
Multiple capture-mark-recapture techniques and a model selection approach to data analysis in Program MARK were used to estimate
the effects of individual age and conspecific density on natural per-capita daily survival probabilities of yellow tang recruits
(recently settled individuals, 30–50 mm total length) and the effects of body size and site on natural per-capita monthly
survival probabilities for juveniles (58–127 mm total length). The models of recruit survival that included additive effects
of density and age were best supported by the data and indicated an increase of survival with age and decrease of survival
with increased conspecific density. At 1 day post-settlement, the model averaged daily per-capita survival probability ranged
from 0.963 (95% CI: 0.932–0.981) at a low density of 0.1 recruits m−2 to 0.848 (95% CI: 0.752–0.911) at a high density of 1.3 recruits m−2. The best supported model of juvenile survival had no effect of fish length or site, with a constant monthly per-capita survival
of 0.939 (95% CI: 0.925–0.950). Only about 1% of recruits may survive to adulthood when protected from fishing. These results
can be used to better analyze and interpret data from protected area monitoring surveys and refine management practices. Continued
long-term monitoring, combined with targeted life history studies and demographic modeling, is needed to further investigate
the population level effects of fishing yellow tang juveniles. 相似文献
82.
J. Rooney E. Donham A. Montgomery H. Spalding F. Parrish R. Boland D. Fenner J. Gove O. Vetter 《Coral reefs (Online)》2010,29(2):361-367
Efforts to map coral reef ecosystems in the Hawaiian Archipelago using optical imagery have revealed the presence of numerous
scleractinian, zoothanthellate coral reefs at depths of 30–130+ m, most of which were previously undiscovered. Such coral
reefs and their associated communities have been recently defined as mesophotic coral ecosystems (MCEs). Several types of
MCEs are found in Hawai‘i, each of which dominates a different depth range and is characterized by a unique pattern of coral
community structure and colony morphology. Although MCEs are documented near both ends of the archipelago and on many of the
islands in between, the maximum depth and prevalence of MCEs in Hawai‘i were found to decline with increasing latitude. The
Main Hawaiian Islands (MHI) had significantly deeper and greater percentages of scleractinian coral, and peaks in cover of
both scleractinian corals and macroalgae occurred within depth bins 20 m deeper than in the Northwestern Hawaiian Islands
(NWHI). Across the archipelago, as depth increased the combined percentage of living cover of mega benthic taxa declined sharply
with increasing depth below 70 m, despite the widespread availability of hard substrate. 相似文献
83.
Hayward JJ Dubovi EJ Scarlett JM Janeczko S Holmes EC Parrish CR 《Journal of virology》2010,84(24):12636-12645
Canine influenza virus (CIV) emerged around 2000 when an equine influenza virus (EIV) was transmitted to dogs in Florida. After 2003, the canine virus was carried by infected greyhounds to various parts of the United States and then became established in several large animal shelters, where it has continued to circulate. To better understand the evolution of CIV since its emergence, and particularly its microevolution in spatially restricted populations, we examined multiple gene segments of CIV from dogs resident in two large animal shelters in New York City during the period 2006 to 2009. In particular, we focused on viruses circulating in the two shelters in 2008 and 2009, which we found shared a common ancestor. While viruses in each shelter were generally monophyletic, we observed some gene flow between them. These shelter sequences were compared to earlier CIV isolates. The shelter viruses differed in 1 to 6 amino acids in each gene segment compared to viruses isolated in Florida between 2003 and 2005 and in Colorado in 2006 and 2008. A comparison of the sequences of equine and canine viruses revealed amino acid replacements that distinguished the viruses from the two hosts, but no clear evidence of positive selection indicative of host adaptation was detected, suggesting that any host range adaptation in CIV occurred early in the emergence of this virus or even before it transferred to dogs. 相似文献
84.
Loertscher J Larson LL Matson CK Parrish ML Felthauser A Sturm A Tachibana C Bard M Wright R 《Eukaryotic cell》2006,5(4):712-722
Endoplasmic reticulum-associated degradation (ERAD) mediates the turnover of short-lived and misfolded proteins in the ER membrane or lumen. In spite of its important role, only subtle growth phenotypes have been associated with defects in ERAD. We have discovered that the ERAD proteins Ubc7 (Qri8), Cue1, and Doa10 (Ssm4) are required for growth of yeast that express high levels of the sterol biosynthetic enzyme, 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGR). Interestingly, the observed growth defect was exacerbated at low temperatures, producing an HMGR-dependent cold sensitivity. Yeast strains lacking UBC7, CUE1, or DOA10 also assembled aberrant karmellae (ordered arrays of membranes surrounding the nucleus that assemble when HMGR is expressed at high levels). However, rather than reflecting the accumulation of abnormal karmellae, the cold sensitivity of these ERAD mutants was due to increased HMGR catalytic activity. Mutations that compromise proteasomal function also resulted in cold-sensitive growth of yeast with elevated HMGR, suggesting that improper degradation of ERAD targets might be responsible for the observed cold-sensitive phenotype. However, the essential ERAD targets were not the yeast HMGR enzymes themselves. The sterol metabolite profile of ubc7Delta cells was altered relative to that of wild-type cells. Since sterol levels are known to regulate membrane fluidity, the viability of ERAD mutants expressing normal levels of HMGR was examined at low temperatures. Cells lacking UBC7, CUE1, or DOA10 were cold sensitive, suggesting that these ERAD proteins have a role in cold adaptation, perhaps through effects on sterol biosynthesis. 相似文献
85.
Garcia L Peltékian E Pastoret C Israeli D Armande N Parrish E 《The journal of gene medicine》1999,1(1):43-55
Inherited muscle diseases are often characterised by widespread muscle damage in the body, limiting the clinical relevance of cell or gene therapy based upon direct injections into muscles. Recent studies have shown, however, that cells originating from the bone marrow are able to target necrosis-regeneration sites as they occur and, in addition, may also participate in the muscle regeneration after undergoing myogenic differentiation. Here, we present a computerised dystrophic muscle simulator that allows the prospecting of different scenarios of both disease evolution and appropriate employment of blood-borne cells as therapeutic shuttles. It provides the option of examining their use either to transfer a healthy gene into the tissue or to impart substances designed to boost its regeneration. One of the major advantages of this tool is that it offers the opportunity of visualising and composing therapeutic strategies in virtual paradigms in which severe clinical situations, not necessarily available in animal models, can be created. The dystrophic muscle simulator is freely accessible via the Genethon web site (www.genethon.fr), and in the online version via http:@www.wiley.co.uk/genmed. 相似文献
86.
The ratio of urinary 2-hydroxyestrone (2-OHE1) to 16alpha-hydroxyestrone (16alpha-OHE1) has been suggested as a potential biomarker for breast cancer risk. We evaluated within-person variability of this biomarker in ten healthy Caucasian women aged 23-58 years. Each study participant was asked to provide an overnight fasting morning urine sample once a week for an average of 8 weeks. These urine samples were assayed for 2-OHE1 and 16alpha-OHE1 by using competitive enzyme immunoassay kits purchased from the ImmunaCare Corporation. The coefficients of variation for urinary 2-OHE1/16alpha-OHE1 over the study period ranged from 13.7 to 59.6% (mean, 33.3%) in our study participants. There was a good correlation between the level of the urinary 2-OHE1/16alpha-OHE1 ratio in any single urine sample and the average ratio over the 8-week study period from the same woman, with the mean correlation coefficient of 0.85. These results indicated that the within-person variation of the 2-OHE1 to 16alpha-OHE1 ratio for most women was moderate and the level of this ratio in a single urine sample, in general, reflects reasonably well the level of this biomarker over a 2-month period. 相似文献
87.
Structures of host range-controlling regions of the capsids of canine and feline parvoviruses and mutants 总被引:3,自引:0,他引:3 下载免费PDF全文
Canine parvovirus (CPV) and feline panleukopenia virus (FPV) differ in their ability to infect dogs and dog cells. Canine cell infection is a specific property of CPV and depends on the ability of the virus to bind the canine transferrin receptor (TfR), as well as other unidentified factors. Three regions in the capsid structure, located around VP2 residues 93, 300, and 323, can all influence canine TfR binding and canine cell infection. These regions were compared in the CPV and FPV capsid structures that have been determined, as well as in two new structures of CPV capsids that contain substitutions of the VP2 Asn-93 to Asp and Arg, respectively. The new structures, determined by X-ray crystallography to 3.2 and 3.3 A resolutions, respectively, clearly showed differences in the interactions of residue 93 with an adjacent loop on the capsid surface. Each of the three regions show small differences in structure, but each appears to be structurally independent of the others, and the changes likely act together to affect the ability of the capsid to bind the canine TfR and to infect canine cells. This emphasizes the complex nature of capsid alterations that change the virus-cell interaction to allow infection of cells from different hosts. 相似文献
88.
Slebos RJ Little RE Umbach DM Antipkin Y Zadaorozhnaja TD Mendel NA Sommer CA Conway K Parrish E Gulino S Taylor JA 《Mutation research》2004,559(1-2):143-151
Knowledge about possible genotoxic effects of low-dose radiation on the human germline is limited and relies primarily on extrapolations from high-dose exposures. To test whether ionizing radiation can cause paternal genetic mutations that are transmitted to offspring, we enrolled families of 88 Chernobyl cleanup workers exposed to ionizing radiation. We analyzed DNA isolated from lymphocytes for mutations via DNA blotting with the multi-locus minisatellite probes 33.6 and 33.15 and via PCR in a panel of six tetranucleotide repeats. Children conceived before and children conceived after their father's exposure showed no statistically significant differences in mutation frequencies. We saw an increase in germline microsatellite mutations after radiation exposure that was not statistically significant. We found no dependence of mutation rate on increasing exposure. A novel finding was that the tetranucleotide marker D7S1482 demonstrated germline hypermutability. In conclusion, our results do not support an increased level of germline minisatellite mutations but suggest a modest increase in germline mutations in tetranucleotide repeats. Small sample size, however, limited statistical power. 相似文献
89.
Parrish JP Kastrinsky DB Stauffer F Hedrick MP Hwang I Boger DL 《Bioorganic & medicinal chemistry》2003,11(17):3815-3838
An extensive series of CBI analogues of the duocarmycins and CC-1065 exploring substituent effects within the first indole DNA binding subunit is detailed. In general, substitution at the indole C5 position led to cytotoxic potency enhancements that can be >/=1000-fold providing simplified analogues containing a single DNA binding subunit that are more potent (IC(50)=2-3 pM) than CBI-TMI, duocarmycin SA, or CC-1065. 相似文献
90.
Genetic Evidence for Natural Hybridization between Species of Dioecious Ficus on Island Populations1
Natural hybrids between Ficus septica and two closely related dioecious species, F. fistulosa and F. hispida, were confirmed using amplified fragment length polymorphisms (AFLP) and chloroplast DNA markers. Ficus species have a highly species‐specific pollination mutualism with agaonid wasps. Therefore, the identification of cases in which breakdown in this sophisticated system occurs and the circumstances under which it happens is of interest. Various studies have confirmed that Ficus species are able to hybridize and that pollinator‐specificity breakdown can occur under certain conditions. This study is the first example in which hybrid identity and the presence of hybrids in the natural distribution of parental species for Ficus have been confirmed with molecular markers. Hybrid individuals were identified on three island locations in the Sunda Strait region of Indonesia. These findings support Janzen's (1979) hypothesis that breakdown in pollinator specificity is more likely to occur on islands. We hypothesized that hybrid events could occur when the population size of pollinator wasps was small or had been small in one of the parental species. Later generation hybrids were identified, indicating that backcrossing and introgression did occur to some extent and that therefore, hybrids could be fertile. The small number of hybrids found indicated that there was little effect of hybridization on parental species integrity over the study area. Although hybrid individuals were not common, their presence at multiple sites indicated that the hybridization events reported here were not isolated incidences. Chloroplast DNA haplotypes of hybrids were not derived solely from one species, suggesting that the seed donor was not of the same parental species in all hybridization events. 相似文献