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851.
852.
The calcium content in the hemolymph and shell of Biomphalaria glabrata (Say, 1818) was determined after exposure to different parasite burdens (5 and 50 miracidia) of Echinostoma paraensei (Lie and Basch, 1967). The snails were dissected 1, 2, 3, and 4 weeks after infection to collect the hemolymph and shell. An increase in calcemia was observed in snails infected with both miracidial doses. A significant decrease in the calcium ions in the shell was observed, coinciding with the calcemia peak in the hemolymph. This indicates greater mobilization of calcium between the shell and hemolymph to regulate the calcium content in the body when the snail is exposed to stress conditions, as has also been observed in some other infected snail species. The results obtained indicate that in this model, the calcium metabolism depends on the miracidial dose used.  相似文献   
853.
Inducible degrader of the low density lipoprotein receptor (IDOL), is an E3 ubiquitin ligase that negatively modulates low density lipoprotein receptor (LDL-R) expression. Genome-wide association studies (GWAS) indicated that genetic variants in IDOL gene contributes to variation in LDL-C plasma levels and the detailed analysis of a specific locus resulted in the identification of the functional common single nucleotide polymorphism (SNP) rs9370867 (c.G1025A, p.N342S) associates with increased LDL-R degradation and increased LDL-C levels. These findings, however, were not confirmed in two other independent cohorts and no data about the impact of this variant on atherosclerosis progression and cardiovascular risk are available. Aim of this study was to investigate the association between a functional variant in IDOL and atherosclerosis progression in an Italian general population. 1384 subjects enrolled in the PLIC study (Progression of Lesions in the Intima of Carotid) were genotyped by Q-PCR allelic discrimination and the association with anthropometric parameters, plasma lipids and the carotid intima media thickness (cIMT) and the impact on cardiovascular disease (CVD) incidence were investigated. The N342S variant was not associated with changes of the plasma lipid profile among GG, AG or AA carriers, including total cholesterol (249±21, 249±19 and 248±21 mg/dl respectively), LDL-C (158±25, 161±22 and 160±23 mg/dL), cIMT (0.74±0.14, 0.75±0.17 and 0.77±0.15 mm) and CVD incidence. In agreement, the expression of LDLR and the uptake of LDL was similar in macrophages derived from GG and AA carriers. Taken together our findings indicate that the N342S variant does not impact plasma lipid profile and is not associated with atherosclerosis progression and CVD in the general population, suggesting that other variants in the IDOL gene might be functionally linked with cholesterol metabolism.  相似文献   
854.
In summer, many temperate bat species use daytime torpor, but breeding females do so less to avoid interferences with reproduction. In forest‐roosting bats, deep tree cavities buffer roost microclimate from abrupt temperature oscillations and facilitate thermoregulation. Forest bats also switch roosts frequently, so thermally suitable cavities may be limiting. We tested how barbastelle bats (Barbastella barbastellus), often roosting beneath flaking bark in snags, may thermoregulate successfully despite the unstable microclimate of their preferred cavities. We assessed thermoregulation patterns of bats roosting in trees in a beech forest of central Italy. Although all bats used torpor, females were more often normothermic. Cavities were poorly insulated, but social thermoregulation probably overcomes this problem. A model incorporating the presence of roost mates and group size explained thermoregulation patterns better than others based, respectively, on the location and structural characteristics of tree roosts and cavities, weather, or sex, reproductive or body condition. Homeothermy was recorded for all subjects, including nonreproductive females: This probably ensures availability of a warm roosting environment for nonvolant juveniles. Homeothermy may also represent a lifesaver for bats roosting beneath loose bark, very exposed to predators, because homeothermic bats may react quickly in case of emergency. We also found that barbastelle bats maintain group cohesion when switching roosts: This may accelerate roost occupation at the end of a night, quickly securing a stable microclimate in the newly occupied cavity. Overall, both thermoregulation and roost‐switching patterns were satisfactorily explained as adaptations to a structurally and thermally labile roosting environment.  相似文献   
855.
During dark‐induced senescence isovaleryl‐CoA dehydrogenase (IVDH) and D‐2‐hydroxyglutarate dehydrogenase (D‐2HGDH) act as alternate electron donors to the ubiquinol pool via the electron‐transfer flavoprotein/electron‐transfer flavoprotein:ubiquinone oxidoreductase (ETF/ETFQO) pathway. However, the role of this pathway in response to other stresses still remains unclear. Here, we demonstrated that this alternative pathway is associated with tolerance to drought in Arabidopsis. In comparison with wild type (WT) and lines overexpressing D‐2GHDH, loss‐of‐function etfqo‐1, d2hgdh‐2 and ivdh‐1 mutants displayed compromised respiration rates and were more sensitive to drought. Our results demonstrated that an operational ETF/ETFQO pathway is associated with plants' ability to withstand drought and to recover growth once water becomes replete. Drought‐induced metabolic reprogramming resulted in an increase in tricarboxylic acid (TCA) cycle intermediates and total amino acid levels, as well as decreases in protein, starch and nitrate contents. The enhanced levels of the branched‐chain amino acids in loss‐of‐function mutants appear to be related to their increased utilization as substrates for the TCA cycle under water stress. Our results thus show that mitochondrial metabolism is highly active during drought stress responses and provide support for a role of alternative respiratory pathways within this response.  相似文献   
856.
Fernando DD 《Proteomics》2005,5(18):4917-4926
The differentially expressed proteins in pollen tubes indicate their specific roles in this stage of male gametophyte development. To isolate these proteins, 2-DE was done using ungerminated pollen and 2-day-old pollen tubes of Pinus strobus. Results show that 645 and 647 protein spots were clearly resolved from pollen grains and pollen tubes, respectively. Thirty-eight protein spots were expressed only in pollen tubes, while 19 increased in intensity. MALDI-TOF MS was used to generate tryptic peptide masses that were submitted to Mascot for identification. Of the differentially expressed proteins, 12% matched with hypothetical proteins, 33% did not hit any protein, and for the 55%, a putative function was assigned based on similarity of sequences with previously characterized proteins. Therefore, pollen tube development can be characterized by the cellular activities that involve metabolism, stress/defense response, gene regulation, signal transduction, and cell wall formation. This study expands our understanding of the changes in protein expression associated with pollen tube development and provides insights into the molecular programs that separate the development of the pollen tubes from pollen grains. This is the first report that describes a global analysis of differentially expressed proteins from the pollen tube of any seed plant.  相似文献   
857.
858.
The Aeta Magbukún are a genetically and culturally distinct group of Indigenous people living in an isolated mountain forest in the municipality of Mariveles, in the province of Bataan, Philippines. This research aims to document some healthcare related information of the people, inform future decisions regarding maximising benefits of modern conveniences, and minimise negative consequences on their culture and health. Using an ethnographic approach, data were collated from a community health survey in combination with field notes from three of the co-authors while living with the Aetas. Despite major implications from rapid ecological and cultural changes, traditional ethnomedical systems continue to be revered as an essential healing practice, although they are increasingly used in conjunction with Western medicines and healthcare. At the Aeta village level, the changing socio-political influence among the kagun (traditional healer), the NGOs, and the Municipal Council in terms of healthcare provision is pivotal, as the kagun has chosen to integrate the Western medicine and healthcare services into their traditional healthcare system, without simply rejecting them. In turn, Western-style healthcare interventions have the potential to be carefully managed to integrate traditional Aeta Magbukún socio-political structures, healthcare, and cultural continuity. The cumulative influence of numerous other novel aspects to Aeta life (e.g., permanent housing, a highway through the village, literacy, cash economies, energy-dense foods, communication/entertainment devices, etc.) will place additional pressure on the traditional ethnomedical healthcare system. However, enabling the continuity of access to appropriate healthcare knowledge (both the transfer of knowledge from Western medicine to the Aeta Magbukún, and vice versa) can assist many cultures through the inherent stresses of increasingly rapid acculturation and development.  相似文献   
859.
Because structural remodeling of several proteins, including ion channels, may underlie the abnormal action potentials of Purkinje cells (PCs) that survive in the 48 hr infarcted zone of the canine heart (IZPCs), we sought to determine the subcellular structure and function of the KV1.5 (KCNA5) protein in single IZPCs. Clustering of the Kv1.5 subunit in axons is regulated by a synapse-associated protein, SAP97, and is linked to an actin-binding protein, cortactin, and an intercellular adhesion molecule, N-cadherin. To understand the functional remodeling of the Kv1.5 channel and its regulation in IZPCs, Kv1.5 currents in PCs were measured as the currents blocked by 10 µM RSD1379 using patch-clamp techniques. Immunocytochemistry and confocal imaging were used for both single and aggregated IZPCs vs normal PCs (NZPCs) to determine the relationship of Kv1.5 with SAP-97, cortactin and N-cadherin. In IZPCs, both the sarcolemma (SL) and intercalated disk (ID) Kv1.5 protein are abundant, and the amount of cytosolic Kv1.5 protein is greatly increased. SAP-97 is also increased at IDs and has notable cytosolic localization suggesting that SAP-97 may regulate the functional expression and stabilization of Kv1.5 channels in IZPCs. Cortactin, which is located with N-cadherin at IDs in NZPCs, remains at IDs but begins to dissociate from N-cadherin, often forming ring structures and colocalizing with Kv1.5 within IZPCs. At the same time, cortactin/Kv1.5 colocalization is increased at the ID, suggesting an ongoing active process of membrane trafficking of the channel protein. Finally, the Kv1.5 current, measured as the RSD1379-sensitive current, at +40 mV did not differ between NZPCs (0.81±0.24 pA/pF, n = 14) and IZPCs (0.83±0.21 pA/pF, n = 13, NS). In conclusion, the subcellular structural remodeling of Kv1.5, SAP97 and cortactin maintained and normalized the function of the Kv1.5 channel in Purkinje cells that survived myocardial infarction.  相似文献   
860.
  1. Invasive alien species are major drivers of global change that can have severe impacts on biodiversity and human well-being. Management strategies implemented to mitigate these impacts are based on a hierarchical approach, from prevention of invasion, via early warning and rapid response, to invasive species management.
  2. We evaluated how different classes of spatially explicit models have been used as predictive tools to improve the effectiveness of management strategies. A review of literature published between 2000 and 2019 was undertaken to retrieve studies addressing alien mammal species through these models.
  3. We collected 62 studies, dealing with 70 (27%) of the 261 mammal species that are considered to be introduced worldwide. Most of the studies dealt with species from the orders Rodentia (34%), Artiodactyla and Carnivora (both 24%); the most commonly studied families were Sciuridae (13%) and Muridae (12%).
  4. Most of the studies (73%) provided spatial predictions of potential species spread, while only ca. 15% of the studies included evaluations of management options. About 29% of the studies were considered useful in risk assessment procedures, but only because they presented climatic suitability predictions worldwide, while studies modelling suitability before a species was introduced locally are still lacking for mammals. With some exceptions, spatially explicit population models are still little used, probably because of the perceived need for detailed information on life history parameters.
  5. Spatially explicit models have been used in relatively few studies dealing with invasive mammals, and most of them covered a restricted pool of species. Most of the studies used climate matching to evaluate the suitability of geographic areas worldwide or the possibility of species that were already established spreading further. Modelling procedures could be a useful tool to assess the risk of establishment for species not yet present in an area but likely to arrive; however, such studies are lacking for mammals.
  相似文献   
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