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81.
LAURA M. BOYKIN RUTH ANN BAGNALL DONALD R. FROHLICH DAVID G. HALL WAYNE B. HUNTER CATHERINE S. KATSAR CINDY L. MCKENZIE ROSEMARIE C. ROSELL ROBERT G. SHATTERS JR. 《Molecular ecology resources》2007,7(6):1202-1204
Twelve polymorphic microsatellite markers were developed from microsatellite‐enriched DNA libraries and mined from an expressed sequence tags library of Diaphorina citri, the vector of the citrus greening disease (huanglongbing). Analysis of 288 individuals from Florida, Texas, and Brazil showed that allelic diversity ranged from three to eight alleles per locus and observed and expected heterozygosities ranged from 0.014 to 0.569 and from 0.052 to 0.653, respectively. These variable microsatellite loci can provide means for assessing overall genetic variation and migration patterns for this agriculturally important pest species. This information can be used to aid in developing successful management strategies. 相似文献
82.
JOHANNES KAMP ROBERT D. SHELDON MAXIM A. KOSHKIN PAUL F. DONALD & ROBERT BIEDERMANN 《Ibis》2009,151(3):452-463
Habitat associations and distribution of breeding Sociable Lapwings were examined in 2004–2008 in central Kazakhstan to develop and assess hypotheses relating to the species' decline and high conservation threat status. At a landscape scale, breeding colonies were strongly positively associated with villages and rivers. Habitat suitability models had very high predictive power and suggested that only 6.6–8.0% of the 30 000-km2 study area was potentially suitable for Sociable Lapwings. Models developed to describe the spatial distribution of nests in one region of Kazakhstan in one year predicted well the distribution of nests in another region, suggesting good generality. At a colony scale, nests were most likely to be found in the most heavily grazed areas, with a high cover of animal dung and bare ground. Despite the low density of human settlements in the study area, most Sociable Lapwing nests were < 2 km from a village. Patterns of grazing were assessed by fitting GPS loggers to cattle. There was a strong positive correlation around villages between grazing intensity and the density of Sociable Lapwing nests, with clear evidence of a threshold of grazing density that needs to be reached before birds will breed. This high degree of synanthropy, perhaps unique in a critically endangered bird, is likely to result from post-Soviet changes in steppe management and offers both threats and opportunities to the species' conservation. 相似文献
83.
The influence of temperature was studied in relation to nitrate reductase activity of creeping bentgrass (Agrostis palustris Huds. cv. ‘Toronto’) a cool season grass and bermudagrass (Cynodon dactylon L. cv. ‘Tifgreen’) a warm season grass. Maximum nitrate reductase activity of both species occurred at 20°C. The nitrate reductase level in bentgrass leaves was reduced when grown at 35°C while bermudagrass leaves were relatively unaffected. The activity per se of the bentgrass enzyme preparation was inhibited rather than synthesis of the enzyme. 相似文献
84.
TAKASHI OBINATA IZUMI HAYASHI DONALD A. FISCHMAN 《Development, growth & differentiation》1974,16(2):105-122
A method is presented for the release of “native” thin filaments from 13-day old embryonic chick muscle without tryptic digestion or desoxycholate (DOC) solubilization of Z bands. The isolated filaments were 50–60 Å in diameter, of variable length, and formed “arrowhead-like” complexes with heavy meromyosin (HMM). In addition, the filaments interacted with purified myosin to form actomyosin as effectively as action extracted from an acetone powder of muscle. The Mg++-dependent ATPase activity and extent of superprecipitation of the synthetic actomyosin required a low concentration of Ca++, strongly suggesting the presence of troponin and tropomyosin on the thin filaments isolated from muscle at this stage of embryogenesis. The native thin filaments were more sensitive to trypsin than synthetic F-actin prepared from an acetone powder based on measurements of flow birefrengence, viscosity and the ability to activate myosin ATPase. 相似文献
85.
GALON I. HALL MARK C. WALLACE WARREN B. BALLARD DONALD C. RUTHVEN III MATTHEW J. BUTLER RACHAEL L. HOUCHIN ROSS T. HUFFMAN RICHARD S. PHILLIPS ROGER APPLEGATE 《The Journal of wildlife management》2007,71(8):2583-2591
ABSTRACT We recorded telemetry locations from 1,129 radiotagged turkeys (Meleagris gallopavo intermedia) on 4 study areas in the Texas Panhandle and southwestern Kansas, USA, from 2000 to 2004. Analyses of telemetry locations indicated both sexes selected riparian vegetative zones. Females did not select grazed or nongrazed pastures for daily movements. However, females did select nongrazed pastures for nest sites on 2 study areas and males selected for grazed pastures at one study area during the breeding season. We compared nest sites (n = 351) to random sites using logistic regression, which indicated height of visual obstruction, percent canopy cover, and percent bare ground provided the highest predictive power (P ≤ 0.003) for characteristics describing nest-site selection. Nest-site vegetative characteristics between vegetative zones differed primarily in composition: upland zone nest sites had more (P ≤ 0.001) shrubs and riparian zone nest sites had more (P ≤ 0.001) grass. There were no differences in measured nest site vegetative characteristics between pasture types, but there were differences between available nesting cover in grazed and nongrazed pastures. Random plots in grazed pastures had less grass cover (P ≤ 0.001) and more bare ground (P = 0.002). Because of cattle impacts on average grass height and availability, grazing would likely have the highest impact on nesting in riparian zones due to turkey use of grass as nesting cover. An appropriate grazing plan to promote Rio Grande turkey nesting habitat would include grazing upland zones in the spring, when it likely has little impact on nesting-site selection, and grazing riparian zones following breeding season completion. Grazing at light to moderate intensities with periods of rest did not affect male turkey pasture use and may have continued to maintain open areas used by male turkeys for displaying purposes. 相似文献
86.
Seventeen species from the Palaeocene and Early Eocene of northern Europe, of which 12 are new, are described belonging to the extinct macroscelidean family Louisinidae, raised here from subfamily rank. These species belong to nine genera, of which five are new. The new genera are Walbeckodon , Berrulestes , Gigarton , Thryptodon , and Prolouisina . The new species are Walbeckodon krumbiegeli , Walbeckodon girardi , Paschatherium levei , Berrulestes phelizoni , Berrulestes pellouini , Berrulestes poirieri , Gigarton meyeri , Gigarton sigogneauae , Gigarton louisi , Thryptodon brailloni , Louisina marci , and Teilhardimys brisswalteri . Prolouisina is erected for ‘Louisina’atavella Russell, 1964. Cladistic analysis was undertaken to understand the relationships within the Louisinidae and between them and the North American family Apheliscidae, in which they had earlier been included as a subfamily. Louisinidae are shown to be sister group to a clade consisting of Apheliscidae plus Amphilemuridae and part of a paraphyletic and polyphyletic Adapisoricidae, all of which are tentatively considered to be stem members of the order Macroscelidea. The most primitive macroscelidid, Chambius, from the Early Eocene of northern Africa is nested within Apheliscidae when postcranial characters were included, but in a majority of cases within the Louisinidae when postcranial characters were excluded. Most species from northern Europe became extinct at the end of the Palaeocene, although the genus Paschatherium survived for much of the Early Eocene and Teilhardimys survived into the earliest Eocene. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 164 , 856–936. 相似文献
87.
Detailed ovipositor morphology has been investigated in representatives of 81 of the more than 120 genera of the parasitic wasp subfamily Doryctinae. Potentially phylogenetically informative variation was found in the microsculpture of the egg canal wall and the presence and degree of development of the valvillus. In all the genera, a socketed seta arises from below each member of the line of ctenidia (comb-like scales) distal to the valvillus (or valvillar region). These subctenidial setae are modified in two groups of genera. In the Holcobraconini (= Odontobraconini) together with the genera Acanthodoryctes, Binarea, Monarea , and Liobrucon , the setae are extremely flattened producing overlapping leaflet-like structures. In some of these, groups of leaflets are further modified to form fans that protrude into the egg canal. In Schlettereriella and Leptospathius the basal seta is highly branched and rather flattened and may serve a similar function to the valvillus which in these two genera is extremely reduced. In Doryctes and Neodoryctes , there is a distinctive type of bar-like sculpture anterior to the valvillus and a single large crescentic bar posterior to the valvillus. These modifications are suggested as possible synapomorphies (in lieu of an analysis) for their respective groups of genera. Several other characters are also described and illustrated. CO 1998 The Norwegian Academy of Science and Letters 相似文献
88.
89.
DONALD L. J. QUICKE 《Zoologica scripta》1989,18(1):139-143
Fuvihracon gen.n. (typc-species: Fuvibracon gauldi sp.n.) and Spurhulibrucon (type-species: Sparhulibracon dayi sp.n.), both lrom Brunei, are described and illustrated. The relationships of the two new genera and of the Carnpyloneurus Szépligeti and Chelonogaslra Ashmead generie groups are discussed. 相似文献
90.
An electron microscopic survey of antenna cleaner morphology, mainly in non-aculcate Hymenoptera, is presented. Modified, scale- or paddle-shaped setae on the fore basitarsus were found to be widely distributed throughout the order, but were particularly well developed in the Xyeloidea. Megalodontoidea, Blasticotomidae, Siricoidca, Orussoidea, Cephoidea and Chalcidoidea. as well as in the aculeate family Formicidae. A comb of fine setae on the fore basitarsus was present in all Apocrita, with the exception of the Trigonalyoidea, Evaniidae, and some families of Chalcidoidea, but among the symphytan families was present only in the Orussidae. Members of the symphytan family, Anaxyelidae have a distinct line of discrete setae in the same position as the fine comb of the Orussidae and apocritans which we term a protocomb; members of the Cephidae also show an indication of a protocomb, in the form of a line of more widely spaced, erect setae, that could form part of the same transition series. Members of the Trigonalyoidea and of the Evaniidae have no comb of fine setae but do possess one or more rows of highly modified, plate-like structures on the fore basitarsi. 相似文献