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101.
D K Miller S Sadowski D D Soderman F A Kuehl 《The Journal of biological chemistry》1985,260(2):1006-1014
A bovine aortic endothelial cell (EC) line released prostacyclin (greater than 1 pmol/10(+5) EC cells) when incubated with fMet-Leu-Phe (FMLP)-stimulated rat and human neutrophils (PMNs). This prostaglandin (PG) I2 was shown to come from the ECs and not from the PMNs by radioactive, high-performance liquid chromatography, and immunochemical criteria. Both FMLP-stimulated rat peritoneal and human peripheral PMNs as well as their stimulated cell-free supernatants and unstimulated sonicates could elicit the release of PGI2 from ECs. Since phorbol myristate acetate stimulated PMN adherence but elicited little PGI2 release from ECs, the PGI2 stimulation in ECs is unrelated to PMN adhesion. The addition of catalase and superoxide dismutase to FMLP-stimulated PMNs enhanced rather than reduced PGI2 formation, indicating that activated oxygen products of the PMN are not responsible for the induction of PGI2. Incubation of ECs with leukotriene (LT) B4, LTC4, or LTD4 did not trigger PGI2 release nor did aspirin pretreatment of the PMNs reduce the PGI2 induction. These data suggest that arachidonic acid metabolites of the PMNs were not responsible for the PGI2 induction. Available data indicates that the PMN factor that stimulates PGI2 from ECs is either released concomitantly with the azurophilic granules or is closely related to this event. 相似文献
102.
Zhengqiu Cai Cynthia Penaflor Jennifer V Kuehl James Leebens-Mack John E Carlson Claude W de Pamphilis Jeffrey L Boore Robert K Jansen 《BMC evolutionary biology》2006,6(1):77-20
Background
The magnoliids with four orders, 19 families, and 8,500 species represent one of the largest clades of early diverging angiosperms. Although several recent angiosperm phylogenetic analyses supported the monophyly of magnoliids and suggested relationships among the orders, the limited number of genes examined resulted in only weak support, and these issues remain controversial. Furthermore, considerable incongruence resulted in phylogenetic reconstructions supporting three different sets of relationships among magnoliids and the two large angiosperm clades, monocots and eudicots. We sequenced the plastid genomes of three magnoliids, Drimys (Canellales), Liriodendron (Magnoliales), and Piper (Piperales), and used these data in combination with 32 other angiosperm plastid genomes to assess phylogenetic relationships among magnoliids and to examine patterns of variation of GC content. 相似文献103.
Mary M. Guisinger Timothy W. Chumley Jennifer V. Kuehl Jeffrey L. Boore Robert K. Jansen 《Journal of molecular evolution》2010,70(2):149-166
Plastid genomes of the grasses (Poaceae) are unusual in their organization and rates of sequence evolution. There has been
a recent surge in the availability of grass plastid genome sequences, but a comprehensive comparative analysis of genome evolution
has not been performed that includes any related families in the Poales. We report on the plastid genome of Typha latifolia, the first non-grass Poales sequenced to date, and we present comparisons of genome organization and sequence evolution within
Poales. Our results confirm that grass plastid genomes exhibit acceleration in both genomic rearrangements and nucleotide
substitutions. Poaceae have multiple structural rearrangements, including three inversions, three genes losses (accD, ycf1, ycf2), intron losses in two genes (clpP, rpoC1), and expansion of the inverted repeat (IR) into both large and small single-copy regions. These rearrangements are restricted
to the Poaceae, and IR expansion into the small single-copy region correlates with the phylogeny of the family. Comparisons
of 73 protein-coding genes for 47 angiosperms including nine Poaceae genera confirm that the branch leading to Poaceae has
significantly accelerated rates of change relative to other monocots and angiosperms. Furthermore, rates of sequence evolution
within grasses are lower, indicating a deceleration during diversification of the family. Overall there is a strong correlation
between accelerated rates of genomic rearrangements and nucleotide substitutions in Poaceae, a phenomenon that has been noted
recently throughout angiosperms. The cause of the correlation is unknown, but faulty DNA repair has been suggested in other
systems including bacterial and animal mitochondrial genomes. 相似文献
104.
Joel O. Wertheim Reilly Hostager Diane Ryu Kevin Merkel Samuel Angedakin Mimi Arandjelovic Emmanuel Ayuk Ayimisin Fred Babweteera Mattia Bessone Kathryn J. Brun-Jeffery Paula Dieguez Winnie Eckardt Barbara Fruth Ilka Herbinger Sorrel Jones Hjalmar Kuehl Kevin E. Langergraber Kevin Lee Nadege F. Madinda Sonja Metzger Lucy Jayne Ormsby Martha M. Robbins Volker Sommer Tara Stoinski Erin G. Wessling Roman M. Wittig Yisa Ginath Yuh Fabian H. Leendertz Sbastien Calvignac-Spencer 《Molecular biology and evolution》2021,38(7):2818
Viruses closely related to human pathogens can reveal the origins of human infectious diseases. Human herpes simplexvirus type 1 (HSV-1) and type 2 (HSV-2) are hypothesized to have arisen via host-virus codivergence and cross-species transmission. We report the discovery of novel herpes simplexviruses during a large-scale screening of fecal samples from wild gorillas, bonobos, and chimpanzees. Phylogenetic analysis indicates that, contrary to expectation, simplexviruses from these African apes are all more closely related to HSV-2 than to HSV-1. Molecular clock-based hypothesis testing suggests the divergence between HSV-1 and the African great ape simplexviruses likely represents a codivergence event between humans and gorillas. The simplexviruses infecting African great apes subsequently experienced multiple cross-species transmission events over the past 3 My, the most recent of which occurred between humans and bonobos around 1 Ma. These findings revise our understanding of the origins of human herpes simplexviruses and suggest that HSV-2 is one of the earliest zoonotic pathogens. 相似文献
105.
Background
When natural hybridization occurs at sites where the hybridizing species differ in abundance, the pollen load delivered to the rare species should be predominantly from the common species. Previous authors have therefore proposed a hypothesis on the direction of hybridization: interspecific hybrids are more likely to have the female parent from the rare species and the male parent from the common species. We wish to test this hypothesis using data of plant hybridizations both from our own experimentation and from the literature.Results
By examining the maternally inherited chloroplast DNA of 6 cases of F1 hybridization from four genera of plants, we infer unidirectional hybridization in most cases. In all 5 cases where the relative abundance of the parental species deviates from parity, however, the direction is predominantly in the direction opposite of the prediction based strictly on numerical abundance.Conclusion
Our results show that the observed direction of hybridization is almost always opposite of the predicted direction based on the relative abundance of the hybridizing species. Several alternative hypotheses, including unidirectional postmating isolation and reinforcement of premating isolation, were discussed. 相似文献106.
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
107.
108.
Hormonal regulation of preputial gland function in male Microtus montanus, the montane vole 总被引:1,自引:0,他引:1
C N Rowsemitt C J Welsh M C Kuehl R E Moore L L Jackson 《Comparative biochemistry and physiology. A, Comparative physiology》1988,90(1):195-200
1. Preputial gland function in male Microtus montanus is androgen-dependent, both in terms of preputial weights and in the production of a series of lipids which are present in M. montanus and absent from Microtus pennsylvanicus. 2. Production of these species-typical lipids is decreased but not eliminated in castrates, as well as in adrenalectomized castrates treated with corticosterone. Therefore, in the total absence of androgens, a low level of these lipids is still produced. 3. 5 alpha-dihydrotestosterone and 17 beta-estradiol enanthate have limited effects on maintenance of preputial weight, suggesting that testosterone itself is the active steroid in the preputial gland of this species. 相似文献
109.
Y W Brans T J Kuehl D L Shannon P Reyes E M Menchaca B A Puleo 《Journal of medical primatology》1985,14(5):263-270
Water contents of the various body water compartments were estimated in 16 nonpregnant adult female baboons and compared to human data. Total body water, extracellular water, and plasma volumes were determined by dilution studies. Intracellular water, interstitial water, blood volume, and red cell volume were calculated. The data were compatible with the finding that baboon females probably have less body fat than their human counterparts. Our data establish a basis for longitudinal studies of the changes in body water content and distribution during normal and pathological pregnancies. 相似文献
110.
Zhengqiu Cai Mary Guisinger Hyi-Gyung Kim Elizabeth Ruck John C. Blazier Vanity McMurtry Jennifer V. Kuehl Jeffrey Boore Robert K. Jansen 《Journal of molecular evolution》2008,67(6):696-704
The plastid genome of Trifolium subterraneum is 144,763 bp, about 20 kb longer than those of closely related legumes, which also lost one copy of the large inverted repeat
(IR). The genome has undergone extensive genomic reconfiguration, including the loss of six genes (accD, infA, rpl22, rps16, rps18, and ycf1) and two introns (clpP and rps12) and numerous gene order changes, attributable to 14–18 inversions. All endpoints of rearranged gene clusters are flanked
by repeated sequences, tRNAs, or pseudogenes. One unusual feature of the Trifolium
subterraneum genome is the large number of dispersed repeats, which comprise 19.5% (ca. 28 kb) of the genome (versus about 4% for other
angiosperms) and account for part of the increase in genome size. Nine genes (psbT, rbcL, clpP, rps3, rpl23, atpB, psbN, trnI-cau, and ycf3) have also been duplicated either partially or completely. rpl23 is the most highly duplicated gene, with portions of this gene duplicated six times. Comparisons of the Trifolium plastid genome with the Plant Repeat Database and searches for flanking inverted repeats suggest that the high incidence
of dispersed repeats and rearrangements is not likely the result of transposition. Trifolium has 19.5 kb of unique DNA distributed among 160 fragments ranging in size from 30 to 494 bp, greatly surpassing the other
five sequenced legume plastid genomes in novel DNA content. At least some of this unique DNA may represent horizontal transfer
from bacterial genomes. These unusual features provide direction for the development of more complex models of plastid genome
evolution.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献