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711.
712.
《Fungal Ecology》2023
Fungal spores are morphologically highly diverse and are therefore frequently used as diagnostic characters in taxonomy. However, the connection between spore morphology and fungal ecology remains poorly understood. Using phylogenetic comparative analyses, we investigated the putative relationships between four ascospore traits and the dominant place of infection, host ecology, and host taxonomic placement in 123 species of biotrophic parasites of bryophytes. Ascospore shape, ornamentation height and relative lipid content are significantly correlated in bryophilous Pezizales. Species attached by their hyphae to bryophyte rhizoids have more globose ascospores with higher ornamentation and relative lipid content than species attached to aboveground organs. Furthermore, some ascospore traits are significantly associated with host lifespan, habitat preferences, and taxonomic placement of their host bryophytes. Our results suggest that the ascospore morphology in this fungal group is closely linked to its ecology and several of the detected relationships point to the existence of distinct dispersal strategies. 相似文献
713.
714.
Structure and productivity along a tree height gradient in a Kandelia obovata mangrove forest in the Manko Wetland, Okinawa Island, Japan 总被引:3,自引:0,他引:3
Rempei Suwa Kangkuso Analuddin Md. Nabiul Islam Khan Akio Hagihara 《Wetlands Ecology and Management》2008,16(4):331-343
Tree height (H) of Kandelia obovata trees decreased sharply from 5 m at the forest interior behind the terrestrial forest to 1.5 m at the forest edge near the
river bank according to an increase in the yearly waterlogged period along a belt transect. The decreasing tree stature was
attributed to a decrease in the asymptote of H in the D
0.1 (stem diameter at H/10)-H relationship toward the edge. The K. obovata trees were well classified into interior and edge types using a discriminant function based on the habitat-specific D
0.1–H relationships. Allometric equations, as a function of D
0.12
H, differed significantly between the interior and edge types in the estimation of the phytomasses of stems and leaves, and
the leaf area per tree. On the other hand, common allometric equations were successfully established in the estimation of
respective phytomasses of aboveground parts and branches. Biomass and leaf area index decreased toward the forest edge. The
biomass allocation to stems decreased toward the edge, whereas those to branches and leaves increased. A dramatic change in
stem diameter increment resulted in differences in the D
0.1–H relationship along the tree height gradient. Relative growth rate of biomass and light-saturated net photosynthesis, which
paralleled net assimilation rate from the interior to the edge, showed their maximum peaks in the middle of the belt transect.
This indicates that there exists an optimal environmental condition for growth of K. obovata trees. Leaf nitrogen content tended to increase to the edge with increasing waterlogged period. 相似文献
715.
Urban A. Kiernan Dobrin Nedelkov Kemmons A. Tubbs Eric E. Niederkofler Randall W. Nelson 《Clinical proteomics》2004,1(1):7-16
With increased interest in clinical proteomics—the comparative investigation of differential protein expression patterns for
use in the diagnostic and prognostic assessment of disease states—the demand for techniques that can readily identify changes
in select proteome components is greater than ever before. This article describes a targeted proteomics approach to recover
and quantify C-reactive protein (CRP) directly from human plasma. CRP, a putative biomarker for cardiac health, was isolated
from microliter volumes of human plasma by using novel proteomics tools that combine micro-scale affinity capture with matrix
assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) detection. Native CRP was analyzed along
with serum amyloid P component (SAP) and retinol binding protein (RBP), that were intentionally targeted to generate a selected
protein expression profile. A number of qualitative changes were readily observed within these profiles, including micro heterogeneity
in the SAP glycan, C-terminally truncated versions of RBP, and detection of a novel truncated variant of CRP. After quantitative
validation of increasing plasma CRP concentrations, the approach was applied to the analysis of eight plasma samples obtained
from individuals with known medical histories. The result of the analyses are eight protein profiles, revealing increasing
CRP levels that can be associated with individuals ailing from post-surgery inflammation, chronic rheumatoid arthritis, and
recent acute myocardial infarction. The technique described in this article lays the foundation for selected protein profiling
for use in biomarker discovery, as well as in clinical and diagnostic applications. 相似文献
716.
J.C. Coleman C.T. Downs 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2009,154(4):508-513
Mechanisms behind variation in physiological traits may assist in explaining how certain traits have evolved. The ability of mammals to concentrate urine has been seen as an adaptation to xeric environments. Urine osmolality and relative medullary thickness (RMT) are two indices which indicate urine concentrating powers. In addition, mammals living in xeric regions have lower water turnover rates (WTR) than their mesic counterparts. The RMT, urine concentrating ability (UCA) and WTR of the Black-tailed Tree Rat, Thallomys nigricauda, were investigated at three study sites along an aridity gradient. We investigated the extent to which these traits are influenced by evolutionary adaptation and/or phenotypic flexibility. There was no significant difference in RMT between sites and no difference in osmolalities when site and season were taken into account. In addition, there was no significant effect of site and season on WTR. This suggests that these traits might have a genetic basis, and reflect an evolutionary adaptation. Lack of differences in the renal traits in T. nigricauda across their range may be interpreted as lack of phenotypic flexibility. However, as a consequence of the degree of individual variation in the parameters measured there appears to be phenotypic flexibility with individuals responding to their specific conditions. This has positive implications for the survival of the species in the light of climate change. 相似文献
717.
W.A. Ramoska 《Journal of invertebrate pathology》1984,43(3):389-394
Beauveria bassiana conidia were bioassayed for pathogenicity against adult chinch bugs, Blissus leucopterus leucopterus, at varying percent relative humidities (RH). The conidia were found to be invasive and pathogenic at all humidities tested. Normal fungal replication and conidiogenesis, however, occurred only on the hosts incubated at the 75% or higher RH levels. 相似文献
718.
A carrier for entomopathogenic nematodes based on an edible-to-insects calcium alginate gel was developed. The alginate system was produced by external setting through an interaction between an aqueous sodium alginate mixture and calcium ions under acidic conditions. Sodium hexa-metaphosphate was used to control gel formation. Yeast extract used in the gel as a phagostimulant for Spodoptera littoralis larvae improved the insect's relative consumption rate and digestibility. The nematodes in the gel effectively controlled the larvae in a 24-h leaf bioassay, although nematode survival in the gel was ~ 50%. Gels subjected to 31% relative humidity (RH) prior to larval feeding became desiccated and were inedible to insects. However, gels at 61% RH supported larval feeding, although the water loss from the gel due to evaporation from 200-400-mg gel cubes at this humidity exceeded 50%. The gel might be a useful delivery system for nematodes against insects infesting the plant canopy in greenhouses. 相似文献
719.
Alexander Volovics Piet A. Den Van Brandt 《Biometrical journal. Biometrische Zeitschrift》1997,39(2):195-214
Case-cohort and nested case-control sampling methods have recently been introduced as a means of reducing cost in large cohort studies. The asymptotic distribution theory results for relative rate estimation based on Cox type partial or pseudolikelihoods for case-cohort and nested case-control studies have been accounted for. However, many researchers use (stratified) frequency table methods for a first or primary summarization of the most important evidence on exposure-disease or dose-response relationships, i.e. the classical Mantel-Haenszel analyses, trend tests and tests for heterogeneity of relative rates. These can be followed by exponential failure time regression methods on grouped or individual data to model relationships between several factors and response. In this paper we present the adaptations needed to use these methods with case-cohort designs, illustrating their use with data from a recent case-cohort study on the relationship between diet, life-style and cancer. We assume a very general setup allowing piecewise constant failure rates, possible recurrent events per individual, independent censoring and left truncation. 相似文献
720.
An estimator of relative risk in a case control study has been proposed in terms of observed cell frequencies and the probability of disease. The bias of the usual estimator i.e odds ratio as compared to the new estimator has been workedout. The expression of Mean Square Error of proposed estimator has been derived in situations where probability of disease is exactly known and when it is estimated through an independent survey. It has been observed that there is a serious error using odds ratio as an estimate of relative risk when probability of disease is not negligible. In such situations the proposed estimator can be used with advantage. 相似文献