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761.
Reproductive phenology of a wet forest understorey in the Western Ghats, South India 总被引:1,自引:0,他引:1
Rani M. Krishnan 《Global Ecology and Biogeography》2002,11(2):179-182
The reproductive phenology of 60 understorey species was monitored at monthly intervals for 20 months in a medium elevation wet evergreen forest in the Southern Western Ghats. The life forms monitored were herbs (including terrestrial orchids), shrubs and small trees. Flowering and fruiting were non‐uniform with a dry season flowering peak and wet season fruiting peak. Flowering in the understorey correlated negatively with rainfall. No significant correlation was detected for fruiting. Life forms had flowering and fruiting peaks at different times of the year. 相似文献
762.
763.
Using a rapid, quantitative high pressure liquid chromatographic (HPLC) procedure for the separation of S-adenosyl-L-homocysteine (AdoHcy) and its purinic metabolites in rat and mouse brain, kidney and liver, we found that uric acid is the principal catabolic product of AdoHcy metabolism in the liver, but that none forms in brain. Rat kidney formed about 10 times as much uric acid and half as much hypoxanthine as did mouse kidney. The HPLC procedure has been adapted to assay AdoHcy hydrolase activity which was found to be lowest in the brain and highest in the liver. 相似文献
764.
S. Suresh Kumar Lalit Kumar Vikram Sahai Rani Gupta 《Journal of industrial microbiology & biotechnology》2009,36(3):427-432
An alkaline lipase from Trichosporon asahii MSR 54 was used to develop presoak formulation for removing oil stains at ambient temperature. The lipase was produced in
a reactor followed by concentration by ultrafiltration and then it was dried with starch. The biochemical characteristics
of enzyme showed that it was an alkaline lipase having pH activity in the range of pH 8.0–10.0 and temperature in the range
of 25–50°C. The present lipase was active >80% at 25°C. The lipase was cystein activated with fourfold enhancement in presence
of 5 mM cystein and likewise the activity was also stimulated in presence of papain hydrolysate which served as source of
cystein. The presoak formulation consisted of two components A and B, component A was enzyme additive and B was a mixture
of carbonate/bicarbonate source of alkali and papain hydrolysate as source of cystein. The results indicated that the presoaking
in enzyme formulation followed by detergent washing was a better strategy for stain removal than direct washing with detergent
in presence of lipase. Further, it was observed that 0.25% presoak component B in presence of 100 U enzyme component A (0.1 g)
was the best formulation in removing maximum stain from mustard oil/triolein soiled clothes as indicated by increase in reflectance
which was found equal to that of control cloth. The lipase action in presoaked formulation was clearly indicated by quantitated
fatty acid release and also the TLC results of wash water, where oil hydrolytic products were visible only in presence of
enzyme in the treatment. The wash performance carried at 25°C indicated that washing at 25°C was at par with that at 40°C
as indicated by similar reflectance of the washed cloth piece though qualitative fatty acid release was higher at 40°C. 相似文献
765.
We present evidence from experiments on overwintering populations of two Palearctic-Indian latitudinal migratory birds, the
black-headed bunting (Emberiza melanocephala) and the red-headed bunting (E. bruniceps), that the bird’s clock in interaction with day length regulates seasonal rhythms of migration and reproduction such that
physiological conflict between them is reduced. Initiation and termination of the body mass and testicular cycles are separately
regulated photoperiodic events. For example, under stimulatory photoperiods the response curve of body mass does not overlap
with that of the testicular growth. A response-specific photoperiodism is adaptive, since gain in body mass, critical to spring
migration, precedes gonadal recrudescence. Finally, migration as indicated by the night-time migratory restlessness under
experimental situations (e.g., intense locomotion under caged condition-called Zugunruhe) appears to be regulated by a separate circadian oscillator. 相似文献
766.
Callus cultures were initiated from axillary leaves, axillary shoots, hypocotyls, and root segments on Murashige and Skoog
(MS) (1962) medium supplemented with 2,4-D (2 mg l−1) and KN (0.2 mg l−1). Shoots differentiated best from axillary shoot base callus on MS medium containing BA (2 mg l−1). Regenerated shoots rooted best on MS medium containing IBA (2 mg l−1) alone, and IBA (2 mg l−1) with IAA (2 mg l−1). Plantlets were transferred to pots containing sand and soil mixture, acclimatized in a culture room and afterwards transferred
to the glasshouse.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
767.
This study reports the endemism and sexual system in the wet evergreen tree flora of the Western Ghats. A total of 656 species from 66 families and 231 genera were listed. This included a gymnosperm family (Podocarpaceae) and a monocot family (Arecaceae). No family was endemic to the Western Ghats, but 352 species (53%) from 43 families and five genera were endemic. Nearly 35% of the families had no endemics. The largest families with endemics were Dipterocarpaceae (92%), Anacardiaceae (84%), Lauraceae (72%), Fabaceae, Rubiaceae and Myrtaceae (68%). The top five contributing families in the tree flora of the Western Ghats were Euphorbiaceae, Lauraceae, Rubiaceae, Myrtaceae and Annonaceae. The 656 species were largely hermaphrodites (57%) followed by dioecious (20%), polygamous (16%) and monoecious species (5%). The rate of dioecy reported in this study (20%) is higher than reports for Puerto Rico (18%) but lower than the Malaysian rainforest (26%). Structurally, like the Neotropical forests, most evergreen forest types of the Western Ghats could be classified into four ensembles. Yet, the Western Ghats had fewer species than other tropical and Neotropical forests. The proportion of endemics in the ensembles of the Western Ghats ranged from 34% (ensemble IV) to 14% (ensemble I). 相似文献
768.
Abstract. This study examines the understorey shrub community in a wet evergreen forest of South India. The shrub community in the evergreen forests of the Western Ghats, Eastern Ghats, Sri Lanka, South-east Asia, Neotropics, Africa and Madagascar are compared. The shrub community is richer in the Old World Tropics as compared to the Neotropics. The common families in the Old World Tropics are: Rubiaceae, Acanthaceae, Euphorbiaceae, Myrsinaceae and Annonaceae. The number of families constituting the understorey shrub community falls from forty-six (Western Ghats) to thirteen (Central Amazon). The study concludes that the evergreen forests in the Western Ghats probably have the richest understorey shrub community.
Résumé. L'étude concerne la communauté d'arbustes de sous-bois d'une forêt sempervirente du Sud de l'lnde. Les communautés d'arbustes dans les forèts sempervirentes des Ghâts Occidentaux, des Ghâts Orientaux, du Sri Lanka, du Sud-Est Asie, des Néotropiques, de l'Afrique et de Madagascar sont comparées. La communauté d'arbustes est plus riche dans le Vieux Monde Tropical que dans les Néotropiques. Les families communes dans le Vieux Monde Tropical sont; Rubiaceae, Acanthaceae, Euphorbiaceae, Myrsinaceae et Annonaceae. Le nombre de families constituant la communauté d'arbustes de sous-bois varie de 46 (Ghâts Occidentaux) à 13 (Amazonie Centrale). L'étude conclue que les forêts sempervierentes des Ghàts Occidentaux ont probablement la plus riche communauté d'arbustes de sois-bois.
Mots clés. Communauté d'arbustes de sous-bois, forêts sempervirentes, Ghâts Occidentaux, endémisme, Inde. 相似文献
Résumé. L'étude concerne la communauté d'arbustes de sous-bois d'une forêt sempervirente du Sud de l'lnde. Les communautés d'arbustes dans les forèts sempervirentes des Ghâts Occidentaux, des Ghâts Orientaux, du Sri Lanka, du Sud-Est Asie, des Néotropiques, de l'Afrique et de Madagascar sont comparées. La communauté d'arbustes est plus riche dans le Vieux Monde Tropical que dans les Néotropiques. Les families communes dans le Vieux Monde Tropical sont; Rubiaceae, Acanthaceae, Euphorbiaceae, Myrsinaceae et Annonaceae. Le nombre de families constituant la communauté d'arbustes de sous-bois varie de 46 (Ghâts Occidentaux) à 13 (Amazonie Centrale). L'étude conclue que les forêts sempervierentes des Ghàts Occidentaux ont probablement la plus riche communauté d'arbustes de sois-bois.
Mots clés. Communauté d'arbustes de sous-bois, forêts sempervirentes, Ghâts Occidentaux, endémisme, Inde. 相似文献