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111.
Cross-reactive monoclonal antibodies recognizing both herpes simplex virus (HSV) glycoprotein B and a major 63,000-dalton varicella-zoster virus (VZV) envelope glycoprotein were isolated and found to neutralize VZV infection in vitro. None of the other VZV glycoproteins was recognized by any polyclonal anti-HSV serum tested. These results demonstrate that HSV glycoprotein B and the 63,000-dalton VZV glycoprotein share antigenic epitopes and raise the possibility that these two proteins have a similar function in infection.  相似文献   
112.
Population genetics has gained popularity as a method to discover glacial refugia in terrestrial species, but has only recently been applied to the marine realm. The last glacial maxima occurred 20,000 years ago, decreasing sea levels by 120 m and exposing much of the continental shelf in the northern Gulf of Mexico, with the exception of De Soto Canyon (2100 m depth). The goal of this study was to determine whether population dynamics of the giant deep-sea isopod, Bathynomus giganteus, were better explained by habitat diversity or by the past presence of a marine glacial refugium in De Soto Canyon. To accomplish this we (1) measured genetic diversity in De Soto Canyon and adjacent regions, (2) characterized gene flow and connectivity between these regions, and (3) investigated historical changes to population size. We sequenced three mitochondrial loci (12S, 16S, and COI) from 212 individuals and also performed a next-generation sequencing pilot study using double digest Restriction site-Associated DNA sequencing. We found high genetic diversity and connectivity throughout the study regions, migration between all three regions, low population differentiation, and evidence of population expansion. This study suggests that habitat heterogeneity, rather than the presence of a glacial refugium, has had an historical effect on the population dynamics of B. giganteus.  相似文献   
113.
Zimbabwe is experiencing a shift in land‐use, away from livestock farming and towards wildlife conservation. The abandonment of livestock farming may have unforeseen consequences on biodiversity and ecosystem functioning, as cattle kraals create valuable nutrient‐rich patches across the semi‐arid savannah. It is unclear how macroinvertebrates functionally respond to such nutrient‐rich patches in semi‐arid savannahs. We analysed functional diversity of both aboveground and belowground taxa on abandoned cattle kraals and savannah control plots in Save valley Conservancy (SVC). We used distance‐based multivariate techniques to estimate indices of functional diversity. Our results indicated that after two decades of abandonment, kraals had higher functional richness (FRic), functional divergence (FDiv) and functional dispersion (FDis) of macroinvertebrates when both aboveground and belowground species are combined. When aboveground macroinvertebrates were considered alone, no difference was observed for all the considered functional indices. However, only FRic was higher on kraals when belowground macroinvertebrates were separately considered. Our results suggest that two‐decade‐old abandoned kraals may have recovered enough for aboveground species to match the surrounding savannah plot and even surpassed the savannah control for belowground species functional diversity.  相似文献   
114.
Recently, the fossil record of rodents from southwestern Brazilian Amazonia has been reviewed with regards to its diversity as well as its ecological relationships. In the reviews, the necessity to report new specimens collected with stratigraphic control was stated. Here, a new dinomyid specimen collected during a 2015 expedition to the Niterói locality, Acre River, is reported. The material is a fragment of skull with the right P4–M1 and the left P4–M2 preserved. The cheek teeth are protohypsodont, a characteristic employed to differentiate Potamarchinae dinomyids from the euhypsodont dinomyids Eumegamyinae and Tetrastylinae. The occlusal surface of the cheek teeth is composed of lophs with interruptions, showing little wear, which suggests that the specimen is not fully ontogenetically developed. The specimen has a unique combination of characters (protohypsodont and pentalophodont cheek teeth, with the leading edges of similar thickness to the trailing edges, and presence of a groove on the bottom of the infraorbital foramen) not present in other known dinomyids, which led us to erect a new taxon. The abundant and diverse fossil record of protohypsodont dinomyids suggests that an important radiative event may have occurred during the middle–late Miocene of northern South America.

http://zoobank.org/urn:lsid:zoobank.org:pub:E082C3C6-47B6-4D83-9009-A64879AAFC7A

http://www.zoobank.org/NomenclaturalActs/16235A7B-A261-445E-8DD4-940AB21DCB06  相似文献   

115.
The Forest and Landscape Restoration movement has emerged as an approach to reconcile biodiversity conservation, ecosystem services provisioning and human well‐being in degraded landscapes, but little is known so far about the potential of different reforestation methods to achieve these objectives. Based on this gap, we assessed the ecological outcomes and local livelihood benefits of community‐managed agroforests and second growth forests to assist natural regeneration in the coastal Atlantic Forest of Brazil. We investigated and compared agroforests and secondary forests according to their structure and floristic composition in 51 circular plots of 314 m², their role in supporting local livelihoods (45 semi‐structured interviews) and the use and cultural importance of plant species (61 interviews). Agroforests and, more remarkably, managed secondary forests (1) re‐established a well‐developed forest structure, with a higher density of tree‐sized individuals and similar basal area compared to nearby old growth forests; (2) were composed by a rich array of native species, including five threatened species, but had lower species richness than old growth remnants; and (3) improved local livelihoods by supplying market valuable and culturally important plants, including 231 native ethnospecies. Overall, local production systems showed remarkable potential to engage smallholders of developing tropical countries in Forest and Landscape Restoration and contribute to achieve its overall goals. We advocate the promotion of these systems as effective Forest and Landscape Restoration approaches in multi‐scale programs and policies.  相似文献   
116.
Brazil is the world's largest coffee producer. Brown eye spot (BES) (Cercospora coffeicola) is a major crop disease that can cause 15–30% production losses and decrease the coffee beverage quality. Although the influence of this disease on beverage quality has been studied, diagrammatic scales for assessment of the disease severity in berries are still unexplored. Thus, this study has developed and validated diagrammatic scales to assess the severity of BES. Two diagrammatic scales were designed to assess the disease in berries, which can be yellow or red depending on the cultivar. The scale of yellow berries had nine grades: grade 0: 0%; 1: 0.1–5.0%; 2: 5.1–10.0%; 3: 10.1–15.0%; 4: 15.1–20.0%; 5: 20.1–30.0%; 6: 30.1–40.0%; 7: 40.1–60.0%; and 8: higher than 60.0%, while the scale of red berries had eight grades: grade 0: 0%; 1: 0.1–2.5%; 2: 2.6–5.0%; 3: 5.1–10.0%; 4: 10.1–20.0%; 5: 20.1–30.0%; 6: 30.1–50.0%; and 7: higher than 50.0% severity. Using scales improved accuracy and precision with R2 = 0.99 and provided good repeatability and reproducibility of assessments of disease severity. Both scales can be used because the different berry colour influenced the accuracy and precision between the scales.  相似文献   
117.
Understanding the patterns and intensity of anthropogenic impacts on habitats is important in the conservation of tropical ecosystems. The aim of the study was to establish the associated edge effects of anthropogenic disturbances on vegetation in western Umfurudzi Park, Zimbabwe. Three study strata were established using distance from the boundary into the park. Vegetation attributes and anthropogenic disturbance levels data were collected in 2012. Significant differences (P < 0.05) were noted on tree and shrub density, woody plant height, woody plant diversity, grass height and grass sward width across the three strata. Land clearing, livestock grazing and firewood collection were the most frequent and pronounced disturbances occurring along the park boundary. These disturbances decreased in intensity as distance from the boundary increased. We recommend the following: (i) the need to revisit the buffer zone concept and policy measures associated with ecosystem services and goods provision for communities surrounding protected areas, (ii) engaging neighbouring communities on sustainable ways of deriving ecosystem goods and services from buffer zones and protected areas and (iii) further studies on the regeneration and recovery of cleared patches along the boundary and their use by wildlife species in the park.  相似文献   
118.
Attempts to achieve a fair metabolic equilibrium in a young woman with brittle diabetes by continuous subcutaneous, intramuscular, and continuous intravenous administration of insulin were unsuccessful. Continuous intraperitoneal administration of insulin through a permanently inserted polyethylene catheter connected to an open-loop peristaltic pump led to an appreciable improvement in mean blood glucose concentration, mean amplitude of glycaemic excursions, and M value and to normalisation of intermediate metabolic products. The peritoneal catheter was well tolerated for over 120 days without appreciable adverse effects. This case suggests that long-term intraperitoneal administration of insulin is a feasible therapeutic approach in the management of brittle diabetes.  相似文献   
119.
Sera from a patient with a chronic Epstein Barr virus (EBV) infection contained unusually high anti-EBV antibody titers (1:2560 to 1:10,240 for EA(D) and 1:5,120 to 1:40,960 for VCA). One of these serum samples was shown by immunoprecipitation to recognize at least 11 EBV-specific proteins from virus producer cells labeled in vivo and 10 EBV-specific proteins from in vitro translations of producer cell mRNA. Six of the in vivo labeled proteins (135,000, 89,000, 50,000 to 55,000 doublet, 46,000, and 34,000 daltons) are "early" by their resistance to phosphonoacetic acid, and five (350,000, 220,000, 160,000, 140,000, and 85,000 daltons) are "late" membrane and capsid proteins. The EBV-specific proteins immunoprecipitated from in vitro translations had molecular masses of 150,000, 140,000, 115,000, 52,000, 50,000, 45,000, 34,000, 29,000, 17,000, and 15,000. Subcellular fractionation studies of cells labeled in vivo revealed that the 135,000-dalton protein and part of the 50,000 to 55,000 dalton protein doublet were found in both the nuclear and the cytoplasmic fractions, and thus are good candidates to be components of the EA(D) diffuse-type immunofluorescence observed with many EA-positive sera.  相似文献   
120.
THE INTERMEDIARY METABOLISM OF THE MYCOBACTERIA   总被引:7,自引:1,他引:6       下载免费PDF全文
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