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101.
102.
Mineral licks are key ecological resources for many species of birds and mammals in Amazonia, providing essential dietary nutrients and clays, yet little is known about which species visit and their behaviors at the mineral licks. Studying visitation and behavior at mineral licks can provide insight into the lives of otherwise secretive and elusive species. We assessed which species visited mineral licks, when they visited, and whether visits and the probability of recording groups at mineral licks were seasonal or related to the lunar cycle. We camera trapped at 52 mineral licks in the northeastern Peruvian Amazon and detected 20 mammal and 13 bird species over 6,255 camera nights. Generalized linear models assessed visitation patterns and records of groups in association with seasonality and the lunar cycle. We report nocturnal curassows (Nothocrax urumutum) visiting mineral licks for the first time. We found seasonal trends in visitation for the black agouti (Dasyprocta fuliginosa), red howler monkey (Alouatta seniculus), blue‐throated piping guan (Pipile cumanensis), red brocket deer (Mazama americana), collared peccary (Pecari tajacu), and tapir (Tapirus terrestris). Lunar trends in visitation occurred for the paca (Cuniculus paca), Brazilian porcupine (Coendou prehensilis), and red brocket deer. The probability of recording groups (>1 individual) at mineral licks was seasonal and related to lunar brightness for tapir. Overall, our results provide important context for how elusive species of birds and mammals interact with these key ecological resources on a landscape scale. The ecological importance of mineral licks for these species can provide context to seasonal changes in species occupancy and movement.

Many species of animals in the Amazon visit mineral licks, consuming soil to supplement their diet. Using camera trap data, we show that visits to mineral licks are seasonal for many species. These trends in visitation are likely due to species‐specific factors such as reproduction, predator avoidance, seasonal diet shifts, and resource use.  相似文献   
103.
Zusammenfassung 1. Um die Wechselbeziehung zwischen Substrat und Bewuchs zu untersuchen, wurden natürlich gewachsene Gesteine im Norden der Insel Sylt neben dem Hafen von List am Anleger der dänischen Autofähre angebracht und in den Jahren 1971 bis 1973 regelmäßig kontrolliert.2. Abiotische Faktoren (Position, Wassertemperatur) und biotische Faktoren (Planktongehalt, Konkurrenten, Weidegänger und Räuber) beeinflußten die Entwicklung des Bewuchses.3. Die Wechselbeziehungen zwischen Plankton- und Bewuchsorganismen sowie der Wassertemperaturen spiegelten sich während der Jahre 1971 und 1972 in quantitativen und qualitativen Populationsunterschieden wider.4. Nach einer Frostperiode im März 1971 war das Plankton individuenärmer als 1972. Die Besiedlung vonBalanus balanoides setzte später und weniger dicht als im folgenden Jahr nach einem milden Winter ein. Nachdem sich im Mai 1971 das Wasser des Wattenmeeres in wenigen Tagen auf 14° C erwärmte, entwickelten sich einige meroplanktische Formen fast explosionsartig. Es folgte auf den Substraten eine intensive Besiedlung vonMytilus edulis, Polydora ciliata undB. improvisus, die 1972 in dieser Höhe nicht mehr erreicht wurde.5. 1972 herrschten im Gegensatz zum Vorjahr Copepoden und wärmeliebende Formen,Noctiluca miliaris, Oikopleura dioica, im Plankton vor. Unte den Bewuchsorganismen traten die TierartenTubularia larynx, Laomedea flexuosa undLanice conchilega häufiger als 1971 auf.6. Im extrem warmen Sommer 1975 (mittlere Wassertemperatur im August 20° C) siedelte sichElminius modestus zahlreich zwischenBalanus balanoides im oberen Eulitoral an. Der von Australien eingeschleppte Balanide war bisher im Untersuchungsgebiet nur gelegentlich gefunden worden.7. Neben dem Planktongehalt konnten als biotische Faktoren der Einfluß von Konkurrenten, Weidegängern und Räubern erfaßt werden. Konkurrenzen zwischen Balaniden einer oder nahe verwandter Arten regulierten die Abundanz. Nacktschnecken und Pantopoden beeinträchtigten als Weidegänger die Entwicklung von Hydrozoenkolonien, und der SeesternAsterias rubens bestimmte durch seine räuberische Tätigkeit die untere Verbreitungsgrenze vonMytilus edulis und den endemischen Balanidenarten. Die Grenze reichte knapp unter die Mitteltiden-Niedrigwasserlinie.
Fowling studies on natural-stone substrates in the tidal zone of the North Sylt wadden sea
Six different types of test substrates were exposed in the tidal zone of the wadden sea near the harbour of List (island of Sylt, North Sea): chalk of Solnhofen, limestone, mottled sandstone, granite, basalt and basalt-lava. The test substrates were fixed to a pannel at the midtide-high-water-level, the midtide-low-water-level and 75 cm below the latter (sublittoral level). Abiotic and biotic environmental factors decisively affected the growth of settling marine plants and animals. Variations in temperature and salinity as well as in the abundance of planktonic organisms, competitors and predators, caused shiftings in the annual beginning of settlement and in the abundance of settled organisms. Beginning with intense frost in March, the annual dynamics of 1971 were characterised by pronounced oscillations in temperature and salinity. The plankton density was poor in spring. When the sea water suddenly warmed in May, some meroplanktonic larvae appeared in high members. This phenomenon was followed by an intensive settlement on the substrate surfaces. In contrast to 1971, water temperatures remained much more stable in 1972. In this year, holoplanktonic copepods predominated throughout, and settlement was less intensive.
  相似文献   
104.
By applying accurate sectioning methods to well-ordered muscles obtained using “in situ” fixation, new details of the structure of the M-band and M-region of frog sartorius muscle have been obtained. Results are described which support the three-dimensional M-band model proposed by Knappeis & Carlsen (1968) but which conflict with the model proposed by Pepe (1975). In addition, new bridge-like structures have been observed both in the M-band (in addition to the well-known M-bridges) and at the edge of the M-region (pseudo H-zone). Finally, it is noted that all of the results presented here provide support for the idea that the myosin crossbridges in this muscle are arranged on a three-stranded helix.  相似文献   
105.
Numerous recent studies have illuminated global distributions of human cases of dengue and other mosquito-transmitted diseases, yet the potential distributions of key vector species have not been incorporated integrally into those mapping efforts. Projections onto future conditions to illuminate potential distributional shifts in coming decades are similarly lacking, at least outside Europe. This study examined the global potential distributions of Aedes aegypti and Aedes albopictus in relation to climatic variation worldwide to develop ecological niche models that, in turn, allowed anticipation of possible changes in distributional patterns into the future. Results indicated complex global rearrangements of potential distributional areas, which—given the impressive dispersal abilities of these two species—are likely to translate into actual distributional shifts. This exercise also signalled a crucial priority: digitization and sharing of existing distributional data so that models of this sort can be developed more rigorously, as present availability of such data is fragmentary and woefully incomplete.  相似文献   
106.

Introduction

Studies have shown that fat lesions follow resolution of inflammation in the spine of patients with axial spondyloarthritis (SpA). Fat lesions at vertebral corners have also been shown to predict development of new syndesmophytes. Therefore, scoring of fat lesions in the spine may constitute both an important measure of treatment efficacy as well as a surrogate marker for new bone formation. The aim of this study was to develop and validate a new scoring method for fat lesions in the spine, the Fat SpA Spine Score (FASSS), which in contrast to the existing scoring method addresses the localization and phenotypic diversity of fat lesions in patients with axial SpA.

Methods

Fat lesions at pre-specified anatomical locations at each vertebral endplate (C2 lower-S1 upper) were assessed dichotomously (present/absent) on spine MRIs. Two readers independently evaluated MRIs obtained at two time points for 58 patients (Exercise 1), followed by optimization of scoring methodology and reader calibration. Thereafter, the same readers read 135 pairs of MRI scans (Exercise 2; including the 58 pairs from exercise 1 randomly mixed with 77 new pairs).

Results

In Exercise 2, the mean (SD) baseline FASSS score for the two readers was 22.5(29.6) and 21.1(28.0), respectively, and the FASSS change score was 4.2(10.6) and 6.0(12.2). Inter-reader reliability assessed as intra-class correlation coefficients (ICCs) for status and change scores were excellent (0.96 (95% CI (0.94 to 0.97)) and very good (0.86 (0.80 to 0.90)), respectively. The smallest detectable change (SDC) was 3.7 for the 135 patients. Good reliability of change scores was also observed for MRI scans conducted one year apart (ICC 0.74 (95% CI 0.44 to 0.89) and SDC 4.5). For the 58 MRI-pairs assessed in both exercises, inter-reader reproducibility for the total FASSS status score improved from very good (ICCs: 0.89 (95% CI: 0.81 to 0.93) in exercise 1 to excellent in exercise 2 (0.96 (0.93 to 0.98)), and improved substantially for the total change score (from 0.67 (0.51 to 0.80) to 0.83 (0.73 to 0.90).

Conclusions

FASSS meets essential validation criteria for quantification of a common structural abnormality in clinical trials of axial spondyloarthritis.  相似文献   
107.
108.
When bis(o-trifluoromethylphenyl)dithiophosphinic acid (1) is dissolved in methanol, crystals of bis(o-trifluoromethylphenyl)dithiophosphinic methyl ester (2) are formed. The structure of dithiophosphinic methyl ester (2) has been characterized via single-crystal X-ray diffraction and multinuclear NMR studies. Compound 2 is remarkable in that the dithiophosphinic (PS2) core is preserved during this transformation. The transformation to 2 suggests that the o-trifluoromethylphenyl groups on phosphorus assist in retaining the PS2 core, possibly by steric hindrance.  相似文献   
109.
110.
Parasites can cause a broad range of sublethal fitness effects across a wide variety of host taxa. However, a host’s efforts to compensate for possible parasite-induced fitness effects are less well-known. Parental effects may beneficially alter the offspring phenotype if parental environments sufficiently predict the offspring environment. Parasitism is a common stressor across generations; therefore, parental infestation could reliably predict the likelihood of infestation for offspring. However, little is known about relationships between parasitism and transgenerational phenotypic plasticity. Thus, we investigated how maternal and grandmaternal infestation with fleas (Xenopsylla ramesis) affected offspring quality and quantity in a desert rodent (Meriones crassus). We used a fully-crossed design with control and infested treatments to examine litter size, pup body mass at birth, and pup mass gain before weaning for combinations of maternal and grandmaternal infestation status. No effect of treatment on litter size or pup body mass at birth was found. However, maternal and grandmaternal infestation status significantly affected pre-weaning body mass gain, a proxy for the rate of maturation, in male pups. Pups gained significantly more weight before weaning if maternal and grandmaternal infestation statuses matched, regardless of the treatment. Thus, pups whose mothers and grandmothers experienced similar risks of parasitism, either both non-parasitized or both infested, would reach sexual maturity more quickly than those pups whose mothers’ infestation status did not match that of their grandmothers. These results support the contention that parents can receive external cues such as the risk of parasitism, that prompt them to alter offspring provisioning. Therefore, parasites could be a mediator of environmentally-induced maternal effects and could affect host reproductive fitness across multiple generations.  相似文献   
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