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71.
Tan JC Miller BA Tan A Patel JJ Cheeseman IH Anderson TJ Manske M Maslen G Kwiatkowski DP Ferdig MT 《Genome biology》2011,12(4):R35
We present an optimized probe design for copy number variation (CNV) and SNP genotyping in the Plasmodium falciparum genome. We demonstrate that variable length and isothermal probes are superior to static length probes. We show that sample preparation and hybridization conditions mitigate the effects of host DNA contamination in field samples. The microarray and workflow presented can be used to identify CNVs and SNPs with 95% accuracy in a single hybridization, in field samples containing up to 92% human DNA contamination. 相似文献
72.
Structure and organization of the bovine beta-globin genes 总被引:1,自引:0,他引:1
Genomic clones spanning the entire cow beta-globin gene locus have been
isolated and characterized. These clones demonstrate that the linkage of
embryonic-like (epsilon) genes and pseudogenes (psi) to the previously
described fetal (gamma) and adult (beta) genes is as follows: 5'-epsilon
3-epsilon 4-psi 3-beta-epsilon 1-epsilon 2-psi 1- psi 2-gamma-3'. Present
data indicate that, like that of the goat, the fetal and adult genes arose
via block duplication of an ancestral four- gene set:
epsilon-epsilon-psi-beta. This duplication event preceded the divergence of
cows and goats, which occurred greater than or equal to 18-20 Myr ago.
However, cows do not have the additional four-gene block containing a
preadult/stress globin gene (beta C). Furthermore, the cow fetal cluster
contains an extra beta-like pseudogene, which apparently arose by a
small-scale duplication. The fixation of this duplication may indicate a
possible evolutionary role for pseudogenes.
相似文献
73.
Loss of phylogenetic information in chorion gene families of Bombyx mori gene conversion 总被引:1,自引:0,他引:1
Regier JC; Weigmann BM; Leclerc RF; Friedlander TP 《Molecular biology and evolution》1994,11(1):72-87
The silkmoth chorion has provided a stimulating model for the study of
evolution and developmental regulation of gene families. Previous attempts
at inferring relationships among chorion sequences have been based on
pairwise comparisons of overall similarity, a potentially problematic
approach. To remedy this, we identified the alignable regions of low
sequence variability and then analyzed this restricted database by
parsimony and neighbor-joining methods. At the deepest level, the chorion
sequence tree is split into two branches, called "alpha" and "beta." Within
each branch, early- and late-expressing genes each constitute monophyletic
groups, while the situation with middle-expressing genes remains uncertain.
The HcB gene family appears to be the most basal beta-branch group, but
this conclusion is qualified because the effect of gene conversion on
branching order is unknown. Previous studies by Eickbush and colleagues
have strongly suggested that ErA, HcA, and HcB families undergo gene
conversion within a gene family, whereas the ErB family does not. The
occurrence of conversion correlates with a particular tree structure;
namely, branch lengths are much greater at the base of the family than at
higher internodes and terminal branches. These observations raise the
possibility that chorion gene families are defined by gene conversion
events (reticulate evolution) rather than by descent with modification
(synapomorphy).
相似文献
74.
REL Paul T Lafond CDM Müller-Graf S Nithiuthai PT Brey JC Koella 《BMC evolutionary biology》2004,4(1):30
Background
Evolutionary theory suggests that the selection pressure on parasites to maximize their transmission determines their optimal host exploitation strategies and thus their virulence. Establishing the adaptive basis to parasite life history traits has important consequences for predicting parasite responses to public health interventions. In this study we examine the extent to which malaria parasites conform to the predicted adaptive trade-off between transmission and virulence, as defined by mortality. The majority of natural infections, however, result in sub-lethal virulent effects (e.g. anaemia) and are often composed of many strains. Both sub-lethal effects and pathogen population structure have been theoretically shown to have important consequences for virulence evolution. Thus, we additionally examine the relationship between anaemia and transmission in single and mixed clone infections. 相似文献75.
The Glutaraldehyde test (GT), a rapid and inexpensive test, has been utilized empirically for many years in bovine practice
for diagnosing inflammatory diseases. GT is used primarily to demonstrate increased serum concentrations of fibrinogen and
globulin. Glutaraldehyde binds with free amino groups in fibrinogen and immunoglobulin to create a clot in a first degree
chemical reaction. The clotting time of the GT estimates the content of proteins produced in response to inflammation. The
applicability of GT for diagnosing inflammation in the horse has never been investigated. The objective of this study was
to determine the ability of GT to distinguish between acute and chronic inflammatory disease in horses. Thirty-seven horses
with suspected inflammatory diseases were evaluated using the GT, history, complete clinical examination and routine blood
analysis. GT-times, laboratory results and clinical outcome were compared statistically. Horses that were determined to be
acutely affected (based on history, clinical examination and routine blood analysis) tended to have a negative GT (75%). Results
of the GT did not correlate with blood fibrinogen concentration. Positive GT also predicted a fatal outcome in 69% of the
clinical cases. The results of this trial indicate that GT can be a useful screening test to distinguish between acute and
chronic inflammatory disease in horses. 相似文献
76.
77.
78.
The distributions of allele sizes at eight simple-sequence repeat (SSR) ormicrosatellite loci in chimpanzees are found and compared with thedistributions previously obtained from several human populations. Atseveral loci, the differences in average allele size between chimpanzeesand humans are sufficiently small that there might be a constraint on theevolution of average allele size. Furthermore, a model that allows for abias in the mutation process shows that for some loci a weak bias canaccount for the observations. Several alleles at one of the loci (Mfd 59)were sequenced. Differences between alleles of different lengths were foundto be more complex than previously assumed. An 8-base-pair deletion waspresent in the nonvariable region of the chimpanzee locus. This locuscontains a previously unrecognized repeated region, which is imperfect inhumans and perfect in chimpanzees. The apparently greater opportunity formutation conferred by the two perfect repeat regions in chimpanzees isreflected in the higher variance in repeat number at Mfd 59 in chimpanzeesthan in humans. These data indicate that interspecific differences inallele length are not always attributable to simple changes in the numberof repeats. 相似文献
79.
JC de Mauroy HR Weiss AG Aulisa L Aulisa JI Brox J Durmala C Fusco TB Grivas J Hermus T Kotwicki G Le Blay A Lebel L Marcotte S Negrini L Neuhaus T Neuhaus P Pizzetti L Revzina B Torres PJM Van Loon E Vasiliadis M Villagrasa M Werkman M Wernicka MS Wong F Zaina 《Scoliosis》2010,5(1):1-15
Abstract
Thoracic hyperkyphosis is a frequent problem and can impact greatly on patient's quality of life during adolescence. This condition can be idiopathic or secondary to Scheuermann disease, a disease disturbing vertebral growth. To date, there is no sound scientific data available on the management of this condition. Some studies discuss the effects of bracing, however no guidelines, protocols or indication's of treatment for this condition were found. The aim of this paper was to develop and verify the consensus on managing thoracic hyperkyphosis patients treated with braces and/or physiotherapy.Methods
The Delphi process was utilised in four steps gradually modified according to the results of a set of recommendations: we involved the SOSORT Board twice, then all SOSORT members twice, with a Pre-Meeting Questionnaire (PMQ), and during a Consensus Session at the SOSORT Lyon Meeting with a Meeting Questionnaire (MQ).Results
There was an unanimous agreement on the general efficacy of bracing and physiotherapy for this condition. Most experts suggested the use of 4-5 point bracing systems, however there was some controversy with regards to physiotherapeutic aims and modalities.Conclusion
The SOSORT panel of experts suggest the use of rigid braces and physiotherapy to correct thoracic hyperkyphosis during adolescence. The evaluation of specific braces and physiotherapy techniques has been recommended. 相似文献80.
JC Barbero-Alvarez JV Subiela J Granda-Vera C Castagna M Gómez J Del Coso 《Biology of sport / Institute of Sport》2015,32(4):339-344
Despite its growing popularity, few studies have investigated specific physiological demands for elite female futsal. The aim of this study was to determine aerobic fitness in elite female futsal players using laboratory and field testing. Fourteen female futsal players from the Venezuelan National team (age =21.2±4.0 years; body mass =58.6±5.6 kg; height =161±5.0 cm) performed a progressive maximal treadmill test under laboratory conditions. Players also performed a progressive intermittent futsal-specific field test for endurance, the Futsal Intermittent Endurance Test (FIET), until volitional fatigue. Outcome variables were exercise heart rate (HR), VO2, post-exercise blood lactate concentrations ([La]b) and running speeds (km · h-1). During the treadmill test, VO2max, maximal aerobic speed (MAS), HR and peak [La]b were 45.3±5.6 ml · kg-1 · min-1, 12.5±1.77 km · h-1, 197±8 beats · min-1 and 11.3±1.4 mmol · l-1, respectively. The FIET total distance, peak running velocity, peak HR and [La]b were 1125.0±121.0 m, 15.2±0.5 km · h-1, 199±8 beats · min-1 and 12.5±2.2 mmol · l-1, respectively. The FIET distance and peak speed were strongly associated (r= 0.85-87, p < 0.0001) with VO2max and MAS, respectively. Peak HR and [La]b were not significantly different between tests. Elite female futsal players possess moderate aerobic fitness. Furthermore, the FIET can be considered as a valid field test to determine aerobic fitness in elite level female futsal players. 相似文献