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61.
Jayanta K. Bora Vishnu Vardhan Ramesh K. Vijh Ajinkya V. Deshmukh Yellapu Srinivas Ninad Avinash Mungi Shravana Goswami Harshini Jhala Jasbir S. Chauhan Ujjwal Kumar Yadvendradev Jhala 《Restoration Ecology》2024,32(3):e14079
Reintroducing megafauna to their historic range is an effective strategy to halt their extinctions and restore ecosystems. Wild water buffalo (Bubalus arnee) is an endangered megaherbivore that is lost from 95% of its range. About 90% of its global population (less than 4000) resides within India, in two isolated populations: northeast and central India. The central Indian population is on the verge of extinction and warrants urgent conservation interventions. We assess the potential and provide a strategy for reintroducing buffaloes in Kanha National Park, India. Habitat suitability using the global occurrence of buffalo revealed low-lying grasslands with least human pressure found in Kanha (390 km2) to be suitable. Within this suitable range, we evaluated vegetation composition, forage biomass, and potential carrying capacity. Multidimensional ordination classified these suitable sites into moist and dry grassland clusters. Moist grasslands were found to better suit reintroduction due to lower grazing pressure, higher productivity, and availability of perennial water sources. Distinct matriarchal clades of swamp and river buffalo were observed. Within the river buffalo clade, Indian wild buffaloes formed a distinct cluster with close proximity between northeast and central Indian samples, suggesting northeast buffaloes could be sourced for a founding population in Kanha. Following IUCN guidelines, we discuss the reintroduction strategy that could sustain approximately 200 buffaloes in the area and subsequently expand to other suitable habitats in central India. If implemented as proposed, recovery of this lost ecosystem engineer will help to restore grasslands, and swamp habitats, as well as contribute to its global conservation efforts. 相似文献
62.
63.
Raiees Andrabi Rajesh Kumar Manju Bala Ambili Nair Prakash SS Vandana Kushwaha Kalpana Luthra 《Journal of microbiology (Seoul, Korea)》2012,50(5):869-873
Subtypes of human immunodeficiency virus type 1 circulating in 21 north Indian patients were characterized based on the partial sequence of the gp120 envelope protein. A majority of viruses (85.7%, 18/21) were subtype C, while 14.3% (3/21) were subtype A. Sequence analysis revealed that the V3 region was highly conserved compared with V4 and V5. The predicted use of co-receptors indicated exclusive usage of R5, except for two subtype A viruses (AIIMS279 and AIIMS281). Our results demonstrate conservation within the V3 loop of subtype C viruses, and suggest the emergence of non-clade C viruses in the north Indian population. 相似文献
64.
Moghadam M. Ayati H. Shobeiri SS. Rajabian M. Rahbarian R. Sankian M. 《Applied Biochemistry and Microbiology》2022,58(4):443-448
Applied Biochemistry and Microbiology - Vit v 1 as a lipid-transfer protein is a major allergen of grapes (Vitis vinifera) that elicits food allergy in many patients in Iran. Todays, recombinant... 相似文献
65.
Seasonal dynamics in mosquito abundance and temperature do not influence avian malaria prevalence in the Himalayan foothills 下载免费PDF全文
Farah Ishtiaq Christopher G. R. Bowden Yadvendradev V. Jhala 《Ecology and evolution》2017,7(19):8040-8057
We examined seasonal prevalence in avian haemosporidians (Plasmodium and Haemoproteus) in migrant and resident birds in western Himalaya, India. We investigated how infection with haemosporidians in avian hosts is associated with temporal changes in temperature and mosquito abundance along with host abundance and life‐history traits (body mass). Using molecular methods for parasite detection and sequencing partial cytochrome b gene, 12 Plasmodium and 27 Haemoproteus lineages were isolated. Our 1‐year study from December 2008 to December 2009 in tropical Himalayan foothills revealed a lack of seasonal variation in Plasmodium spp. prevalence in birds despite a strong correlation between mosquito abundance and temperature. The probability of infection with Plasmodium decreased with increase in temperature. Total parasite prevalence and specifically Plasmodium prevalence showed an increase with average avian body mass. In addition, total prevalence exhibited a U‐shaped relationship with avian host abundance. There was no difference in prevalence of Plasmodium spp. or Haemoproteus spp. across altitudes; parasite prevalence in high‐altitude locations was mainly driven by the seasonal migrants. One Haemoproteus lineage showed cross‐species infections between migrant and resident birds. This is the first molecular study in the tropical Himalayan bird community that emphasizes the importance of studying seasonal variation in parasite prevalence. Our study provides a basis for further evolutionary study on the epidemiology of avian malaria and spread of disease across Himalayan bird communities, which may not have been exposed to vectors and parasites throughout the year, with consequential implications to the risk of infection to naïve resident birds in high altitude. 相似文献
66.
Landscape‐scale accessibility of livestock to tigers: implications of spatial grain for modeling predation risk to mitigate human–carnivore conflict 下载免费PDF全文
Jennifer R. B. Miller Yadvendradev V. Jhala Jyotirmay Jena Oswald J. Schmitz 《Ecology and evolution》2015,5(6):1354-1367
Innovative conservation tools are greatly needed to reduce livelihood losses and wildlife declines resulting from human–carnivore conflict. Spatial risk modeling is an emerging method for assessing the spatial patterns of predator–prey interactions, with applications for mitigating carnivore attacks on livestock. Large carnivores that ambush prey attack and kill over small areas, requiring models at fine spatial grains to predict livestock depredation hot spots. To detect the best resolution for predicting where carnivores access livestock, we examined the spatial attributes associated with livestock killed by tigers in Kanha Tiger Reserve, India, using risk models generated at 20, 100, and 200‐m spatial grains. We analyzed land‐use, human presence, and vegetation structure variables at 138 kill sites and 439 random sites to identify key landscape attributes where livestock were vulnerable to tigers. Land‐use and human presence variables contributed strongly to predation risk models, with most variables showing high relative importance (≥0.85) at all spatial grains. The risk of a tiger killing livestock increased near dense forests and near the boundary of the park core zone where human presence is restricted. Risk was nonlinearly related to human infrastructure and open vegetation, with the greatest risk occurring 1.2 km from roads, 1.1 km from villages, and 8.0 km from scrubland. Kill sites were characterized by denser, patchier, and more complex vegetation with lower visibility than random sites. Risk maps revealed high‐risk hot spots inside of the core zone boundary and in several patches in the human‐dominated buffer zone. Validation against known kills revealed predictive accuracy for only the 20 m model, the resolution best representing the kill stage of hunting for large carnivores that ambush prey, like the tiger. Results demonstrate that risk models developed at fine spatial grains can offer accurate guidance on landscape attributes livestock should avoid to minimize human–carnivore conflict. 相似文献
67.
Home range and habitat preference of female lions (Panthera leo persica) in Gir forests, India 总被引:1,自引:0,他引:1
Yadvendradev V. Jhala Shomen Mukherjee Nita Shah Kartikeya S. Chauhan Chittranjan V. Dave V. Meena Kausik Banerjee 《Biodiversity and Conservation》2009,18(13):3383-3394
The social organization of Asiatic lions (Panthera leo persica) differs from African lions (P. l. leo) in that breeding lionesses defend resource based territories while male coalitions maximize coverage of female groups. Thus,
lion density in the Gir forests of India is dictated by female territory size. We studied the home range and habitat preference
of lions using radio telemetry on seven lionesses spaced throughout the Gir between 2002 and 2005. Radio locations obtained
by homing in were plotted on a classified (LISS III FCC) habitat map of Gir to obtain habitat use and availability. Habitat
preference was computed using compositional analysis and Ivlev’s index. Average (±SE) 100% Minimum Convex Polygon (MCP) range
of six lionesses was 48.2 ± 10.6 km2, 95% MCP was 34.7 ± 7.8 km2 and 95% fixed kernel range size was 32.5 ± 8.2 km2. Breeding female group density and group size was about 3 per 100 km2 and 1.3 (0.5 SD, n = 45) respectively. Lions were observed to show a habitat preference (c(6df)2 = 11. 4 \chi_{(6df)}^{2} = 11. 4 , P = 0.08), the order of preference was Moist Mixed forests > Mixed forests > Savanna habitats > Teak-Acacia-Zizyphus-Anogeissus forests > Acacia-Lannea-Boswellia forests > Thorn and Scrub forests > Agriculture areas. Habitat preference during the day was for dense vegetation (c(6df)2 = 35 \chi_{(6df)}^{2} = 35 , P < 0.001). At night lions even ventured into agricultural fields. Our data suggests that dense habitats are preferred by lions
in Gir to escape the heat of the day and to be in good cover when human activity was likely to be at its peak within forested
areas. 相似文献
68.
Ishtiaq F Beadell JS Baker AJ Rahmani AR Jhala YV Fleischer RC 《Proceedings. Biological sciences / The Royal Society》2006,273(1586):587-594
The success of introduced species is frequently explained by their escape from natural enemies in the introduced region. We tested the enemy release hypothesis with respect to two well studied blood parasite genera (Plasmodium and Haemoproteus) in native and six introduced populations of the common myna Acridotheres tristis. Not all comparisons of introduced populations to the native population were consistent with expectations of the enemy release hypothesis. Native populations show greater overall parasite prevalence than introduced populations, but the lower prevalence in introduced populations is driven by low prevalence in two populations on oceanic islands (Fiji and Hawaii). When these are excluded, prevalence does not differ significantly. We found a similar number of parasite lineages in native populations compared to all introduced populations. Although there is some evidence that common mynas may have carried parasite lineages from native to introduced locations, and also that introduced populations may have become infected with novel parasite lineages, it may be difficult to differentiate between parasites that are native and introduced, because malarial parasite lineages often do not show regional or host specificity. 相似文献
69.
The cDNA cloning and molecular evolution of reptile and pigeon lactate dehydrogenase isozymes 总被引:1,自引:0,他引:1
The cDNAs encoding lactate dehydrogenase isozymes LDH-A (muscle) and LDH-B
(heart) from alligator and turtle and LDH-A, LDH-B, and LDH-C (testis) from
pigeon were cloned and sequenced. The evolutionary relationships among
vertebrate LDH isozymes were analyzed. Contrary to the traditional belief
that the turtle lineage branched off before the divergence between the
lizard/alligator and bird lineages, the turtle lineage was found to be
clustered with either the alligator lineage or the alligator-bird clade,
while the lizard lineage was found to have branched off before the
divergence between the alligator/turtle and bird lineages. The pigeon
testicular LDH-C isozyme was evidently duplicated from LDH-B (heart), so it
is not orthologous to the mammalian testicular LDH-C isozymes.
相似文献
70.
The non-steroidal anti-inflammatory drug diclofenac is a major cause of the rapid declines in the Indian subcontinent of three species of vultures endemic to South Asia. The drug causes kidney failure and death in vultures. Exposure probably arises through vultures feeding on carcasses of domesticated ungulates treated with the drug. However, before the study reported here, it had not been established from field surveys of ungulate carcasses that a sufficient proportion was contaminated to cause the observed declines. We surveyed diclofenac concentrations in samples of liver from carcasses of domesticated ungulates in India in 2004-2005. We estimated the concentration of diclofenac in tissues available to vultures, relative to that in liver, and the proportion of vultures killed after feeding on a carcass with a known level of contamination. We assessed the impact of this mortality on vulture population trend with a population model. We expected levels of diclofenac found in ungulate carcasses in 2004-2005 to cause oriental white-backed vulture population declines of 80-99% per year, depending upon the assumptions used in the model. This compares with an observed rate of decline, from road transect counts, of 48% per year in 2000-2003. The precision of the estimate based upon carcass surveys is low and the two types of estimate were not significantly different. Our analyses indicate that the level of diclofenac contamination found in carcasses of domesticated ungulates in 2004-2005 was sufficient to account for the observed rapid decline of the oriental white-backed vulture in India. The methods we describe could be used again to assess changes in the effect on vulture population trend of diclofenac and similar drugs. In this way, the effectiveness of the recent ban in India on the manufacture and importation of diclofenac for veterinary use could be monitored. 相似文献