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The high molecular weight glutenin subunits (HMW-GS) play a key role in end-use quality of wheat. Their particular primary structure is mostly derived from DNA sequencing, which gives no information on potential post-translational modifications. This paper reveals the primary structure of HMW-GS 1Dx2 by proteomic analysis. For this purpose, HMW-GS were first isolated from wheat flour (cv. Contra). The relative molecular mass (Mr) of subunit 1Dx2 present in the HMW-GS mixture was then very accurately determined with high-performance liquid chromatography–electrospray ionization-mass spectrometry using a quadrupole-time-of-flight mass analyzer (HPLC–ESI-QTOF-MS). The obtained Mr value (87,105) differed from the value derived from its protein sequence in the NCBI database (87,007). The subunit was further purified by preparative reversed-phase HPLC and partially hydrolyzed with chymotrypsin. The resulting 1Dx2 peptides were then analyzed by HPLC–ESI-MS/MS and the MS data were compared to amino acid sequences in protein databases. The discrepancy between the calculated and the measured Mr of 1Dx2 was explained by a missing proline in the 1Dx2 amino acid sequence from the database and not by any post-translational glycosylation.  相似文献   
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Hoof balance radiographs are commonly used as the basis for corrective farriery decision‐making in horses, however there are limited published data quantifying effects of the stance of the horse or the horizontal radiographic beam angle. In this analytical study, the influence of variation of the horse's stance in the craniocaudal and lateromodial plane on hoof balance measurements as well as the influence of variation of the horizontal radiographic beam angle on dorsopalmar hoof balance measurements was examined. Distal left thoracic limb lateromedial radiographs were acquired using a standardized protocol while varying the craniocaudal stance of five horses, each selected to be sound and conformationally normal. Dorsopalmar foot radiographs were acquired while varying the lateromedial stance; and variable angle horizontal beam dorsopalmar foot radiographs were acquired while keeping the limb position constant. Analyses of measurements demonstrated that hoof pastern angle had a linear relationship (R2 = 0.89, P < 0.001) with craniocaudal stance of the horse. The relationship of joint angle and stance was greater for the distal interphalangeal joint angle (R2 = 0.89, P < 0.001) than the proximal interphalangeal joint angle (R2 = 0.65, P = 0.001). The distal phalanx angle did not change with craniocaudal stance variation. The proximal interphalangeal joint width, distal interphalangeal joint width, or distal phalanx height did not change with lateromedial stance variation, nor within a 15 degree dorsolateral to caudomedial and dorsomedial to caudolateral variation from the dorsopalmar axis. Findings indicated that positioning of the thoracic limb needs to be considered during radiographic interpretation and decision‐making for corrective farriery.  相似文献   
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Context

Cultural landscapes provide essential ecosystem services to local communities, especially in poor rural settings. However, potentially negative impacts of ecosystems—or disservices—remain inadequately understood. Similarly, how benefit–cost outcomes differ within communities is unclear, but potentially important for cultural landscape management.

Objectives

Here we investigated whether distinct forest ecosystem service–disservice outcomes emerge within local communities. We aimed to characterize groups of community members according to service–disservice outcomes, and assessed their attitudes towards the forest.

Methods

We interviewed 150 rural households in southwestern Ethiopia about locally relevant ecosystem services (provisioning services) and disservices (wildlife impacts). Households were grouped based on their ecosystem service–disservice profiles through hierarchical clustering. We used linear models to assess differences between groups in geographic and socioeconomic characteristics, as well as attitudes toward the forest.

Results

We identified three groups with distinct ecosystem service–disservice profiles. Half of the households fell into a “lose–lose” profile (low benefits, high costs), while fewer had “lose–escape” (low benefits, low costs) and “win–lose” (high benefits, high costs) profiles. Location relative to forest and altitude explained differences between the “lose–escape” profile and other households. Socioeconomic factors were also important. “Win–lose” households appeared to be wealthier and had better forest use rights compared to “lose–lose” households. Attitudes towards the forest did not differ between profiles.

Conclusions

Our study demonstrates the importance of disaggregating both ecosystem services and disservices, instead of assuming that communities receive benefits and costs homogenously. To manage cultural landscapes sustainably, such heterogeneity must be acknowledged and better understood.
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Facilitating human-carnivore coexistence is a major conservation concern in human-dominated landscapes worldwide. Useful insights could be gained by studying and understanding the dynamics of human-carnivore coexistence in landscapes in which carnivores and humans have coexisted for a long time. We used a two-pronged approach combining ecological and social data to study coexistence of the brown bear (Ursus arctos) and humans in Transylvania, Romania. First, we surveyed 554 km of walking transects to estimate activity via a bear sign index, namely the proportion of anthills disturbed by bears, and used spatially explicit predictive models to test which biophysical and anthropogenic variables influenced bear activity. Second, we interviewed 86 shepherds and 359 villagers and community representatives to assess conflicts with bears and attitudes of shepherds towards bears. Our interdisciplinary study showed that bears and humans coexisted relatively peacefully despite occasional conflicts. Coexistence appeared to be facilitated by: (1) the availability of large forest blocks that are connected to the source population of bears in the Carpathian Mountains; (2) the use of traditional livestock management to minimize damage from bears; and (3) some tolerance among shepherds to occasional conflict with bears. In contrast, bear activity was unrelated to human settlements, and compensation for livestock losses did not influence people’s attitudes toward bears. Our study shows that coexistence of humans and carnivores is possible, even without direct economic incentives. A key challenge for settings with a discontinuous history of human-carnivore coexistence is to reinstate both practices and attitudes that facilitate coexistence.  相似文献   
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Given its importance in human and canine tumour biology, a profound understanding of tumour hypoxia is of paramount importance. Therefore, the aim of this work was to investigate the relationship between tumour hypoxia and the expression of a number of hypoxia-induced proteins that play a role in tumour metabolism. The hypoxia marker pimonidazole was administered to dogs affected by spontaneous mammary carcinoma and compared with immunohistochemical staining for GLUT1 and 3, HK 2 and CA IX. A statistically significant correlation was found between pimonidazole staining and GLUT1-expression (R = 0.607; p = 0.001). These results indicate a strong interaction between tumour hypoxia and tumour metabolism by the induction of proteins essential to maintain a stable tumour microenvironment.  相似文献   
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The kinetics of heat-induced polymerization of gliadin, that is, a mixture of monomeric wheat storage proteins, was studied using a model system. Samples were heated at pH 6.0 and 8.0 at 110, 120, and 130 °C for up to 240 min, and their extractabilities were compared under nonreducing and reducing (with 1% dithiothreitol) conditions. Extraction media were sodium dodecyl sulfate (SDS) containing buffer (pH 6.8, SDS buffer) and/or 70% ethanol. Gliadin cross-linking mainly resulted from intermolecular disulfide (SS) bond formation. At higher temperatures and, preferably, alkaline pH, intramolecular SS bonds in gliadin underwent β-elimination reactions, leading to the formation of dehydroalanine (DHA) and free sulfhydryl (SH) groups. The latter interchanged rapidly with SS bonds, leading to intermolecular SS bonds and gliadin extractability loss. When free SH groups had been formed, gliadin extractability in SDS buffer decreased following first-order reaction kinetics, the reaction rate constant of which increased with temperature and pH. Furthermore, the extractabilities of α- and γ-gliadin in 70% ethanol decreased according to first-order reaction kinetics. ω-Gliadin extractability was much less affected. Under the experimental conditions, gliadin polymerization through SH-SS interchange occurred much more rapidly than β-elimination of cystine.  相似文献   
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