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91.
In the present study we analyzed medicinal and edible plant utilization in Cuyin Manzano, a small rural population located near the Andean forests of Argentina. We also studied where and when plant knowledge was learned, who the principal transmitters were, and how people were taught. The participants were interviewed individually and at random, by means of a semi-structured questionnaire. Interviews were carried out in 16 families in order to examine the present use of wild plants. The inhabitants of Cuyin Manzano cited 87 plants: 63 medicinal and 24 edible species. They mentioned on average 31 ± 10 species per person. Similar patterns of plant use were found in young and old people alike, irrespective of gender. Learning about useful plants took place at an early age as a result of family tradition. This local knowledge is acquired and taught “by doing,” and is mostly transmitted vertically through family dissemination. Wild plant learning implies the acquisition of plants' physical and functional features as well as their environmental characteristics.  相似文献   
92.
云南省香格里拉大峡谷藏族神山在自然保护中的意义   总被引:11,自引:1,他引:11  
位于云南省西北部迪庆藏族自治州境内的香格里拉大峡谷拥有独特的自然人文景观和丰富的生物多样性。藏族作为当地最重要的原住民族,他们的文化对当地的自然环境具有重要的影响。为了解藏族传统文化中的神山崇拜对香格里拉大峡谷地区自然环境的影响,本文应用民族生态学、植物生态学和文化人类学的研究方法,结合文献资料的分析,对香格里拉大峡谷的藏族神山进行了调查和研究,并对处于不同保护状态下(神山与非神山)的两个典型植物群落即高山松(Pinus densata)群落和云南黄果冷杉(Abies ernestii var. salouenensis)群落进行了比较。结果显示,在相同的样地面积内(20 m×20 m),神山植物群落在物种数量(20,14)和群落盖度(100%,85%)方面都明显高于非神山植物群落(11,2;70%,60%)。结合入户调查资料,发现广泛分布于香格里拉大峡谷的藏族神山构成了一个“自下而上”的乡土保护体系,它不仅在保护生物多样性、维护当地脆弱的生态环境等方面发挥着重要的作用,而且还可以提供多种非林产品,实现多种生态功能。文章探讨了发挥乡土保护体系的保护功效及应用传统文化知识以促进自然保护的重要性,建议应当尊重和保护原住民的传统文化,发掘其中优秀的自然保护知识和经验,引导其发挥更加有效的自然保护功能,使民族传统保护体系成为现代自然保护体系的有力补充。  相似文献   
93.
Uganda has a large population of goats, predominantly from indigenous breeds reared in diverse production systems, whose existence is threatened by crossbreeding with exotic Boer goats. Knowledge about the genetic characteristics and relationships among these Ugandan goat breeds and the potential admixture with Boer goats is still limited. Using a medium‐density single nucleotide polymorphism (SNP) panel, we assessed the genetic diversity, population structure and admixture in six goat breeds in Uganda: Boer, Karamojong, Kigezi, Mubende, Small East African and Sebei. All the animals had genotypes for about 46 105 SNPs after quality control. We found high proportions of polymorphic SNPs ranging from 0.885 (Kigezi) to 0.928 (Sebei). The overall mean observed (HO) and expected (HE) heterozygosity across breeds was 0.355 ± 0.147 and 0.384 ± 0.143 respectively. Principal components, genetic distances and admixture analyses revealed weak population sub‐structuring among the breeds. Principal components separated Kigezi and weakly Small East African from other indigenous goats. Sebei and Karamojong were tightly entangled together, whereas Mubende occupied a more central position with high admixture from all other local breeds. The Boer breed showed a unique cluster from the Ugandan indigenous goat breeds. The results reflect common ancestry but also some level of geographical differentiation. admixture and f4 statistics revealed gene flow from Boer and varying levels of genetic admixture among the breeds. Generally, moderate to high levels of genetic variability were observed. Our findings provide useful insights into maintaining genetic diversity and designing appropriate breeding programs to exploit within‐breed diversity and heterozygote advantage in crossbreeding schemes.  相似文献   
94.
In order to elucidate the domestication history of Peking ducks, 190 blood samples from six Chinese indigenous duck breeds were collected with186 individualsgenotyped by 15 microsatellite markers. Both the FST and Nei’s standard genetic distances (Ds) from the microsatellite data indicated high genetic differentiation between Peking duck and other Chinese indigenous breeds. The haplotype network with mtDNA data showed that most of the Peking duck haplotypes were distinctly different from those of other domestic breeds. Although the H01 haplotype was shared by all domesticated duck breeds, Peking ducks displayed 12 specific domestic duck haplotypes, including four similar haplotypes H02, H04, H08 and H22, that formed a single haplogroup (A). Both H02 and H22 haplotypes were also shared by mallard and Peking ducks, indicating that Peking ducks originated from wild mallard ducks.  相似文献   
95.
通过树脂吸附、离子交换、薄层层析、高效液相色谱系统以及紫外、质谱等分离、纯化和鉴别的方法,从哈茨木霉T2-16菌株发酵液中分离得到一种对豆科作物生长具促进作用的肽类物质。用该肽类物质对豇豆土著根瘤菌进行处理后,用AFLP技术研究了该物质对供试根瘤菌遗传稳定性和在土壤中竞争结瘤能力的影响。结果表明,传代次数和培养温度(28℃~36℃范围)对供试根瘤菌的遗传性状无明显影响,其AFLP指纹未发生明显变化;但经木霉肽类代谢产物处理后,根瘤菌竞争结瘤能力得到提高,为对照根瘤菌的1.53倍。  相似文献   
96.
Q. Wang  J. Pi  J. Shen  A. Pan  L. Qu 《Animal genetics》2018,49(4):326-328
Rumplessness in Hongshan chickens has been reported as a novel sex‐linked characteristic. Re‐sequencing data suggest that a pseudogene on the Z chromosome, LOC431648, is affiliated with this phenotype. In this study, we chose 23 rumpless and 25 normal Hongshan chickens to localize the potential variation by means of a genome‐wide association study using a high density microarray. A region on the Z chromosome was found to be closely associated with rumplessness in Hongshan chickens. The region, located in gene LINGO2, was approximately 3 Mb away from pseudogene LOC431648. The function of this gene has not yet been studied in birds. Differential expression of the candidate genes in the tail feather follicles was not detected by q‐PCR, which suggests that the rumplessness trait could be attributed to other genetic mechanisms.  相似文献   
97.
It was recognized that Geotrichum candidum Link which was selected as the efficient lipase producer formed lipase only in the presence of substrate or its relating compounds such as oils or fatty acids in a cultivation medium. From the experimental results obtained by the cultivation of the microorganism and also by using of washed cells, it seemed that lipase was formed inducibly. It is likely that the produced lipase is localized around the cell wall and membrane and it is released from the cells after a certain period from the inducible synthesis.  相似文献   
98.

Aim

To evaluate how the establishment risk of freshwater fish species from the aquarium trade will change under a climate change scenario forecast for the year 2050.

Location

North America.

Methods

In order to estimate changes in the magnitude of risk across geography and across different species in the aquarium pathway, we considered an integrated approach to modelling the probability of establishment, which simultaneously included proxies of propagule pressure, environmental variables, species traits and interactions between environment and traits. We then used the parameters of our model to predict how the risk of establishment will change under a scenario of climate change forecast for the year 2050.

Results

Our joint model performed better than submodels, suggesting that combining all components is worthwhile. The most predictive factors were precipitation, maximum temperature tolerance, maximum fish length and minimum temperature. Our joint model forecasted a 40% increase in the average risk of establishment by 2050 in the United States. In contrast to our expectations, the absolute establishment risk associated with this pathway remained very low for the entire suite of species in the aquarium trade in northern regions, such as Quebec, Canada. Instead, Florida, which has one of the highest current risks of establishment, was also forecasted to have the greatest absolute risk increase.

Main conclusions

Our methodology for risk assessment allows invasive species management strategies to consider entire suites of species at a time and to forecast establishment risk for each species and location. While the aquarium pathway is likely to become more important for the United States, the Quebec government should prioritize other pathways of introduction in its exotic invasive species strategy. Our approach can be extended to be applied to different sets of species pertaining to the same or different pathways.
  相似文献   
99.
‘Ana‐aosa’, one of the most common marine green algae in Japan, was described as Ulva pertusa Kjellman in 1897 from Hakodate in northern Japan. Ulva pertusa was considered to be a temperate species, with its native distributional range restricted to northeastern Asia. Although this species has been reported from various regions outside northeastern Asia, these records have been explained as non‐indigenous populations. Recently, on the basis of genetic data and nomenclatural priority, U. pertusa was synonymized with U. australis Areschoug, a species described in 1851 from specimens collected in South Australia. Based on genetic studies, Australian populations identified as U. pertusa had been considered to have originated from Japan. However, the published genetic data on U. australis in Australia have been based only on recent collections and no historical specimens have been examined. We tested the hypothesis that native (true) U. australis is an independent species of very similar morphology to U. pertusa, but that its natural domination of shoreline habitats has been suppressed by introduced populations of U. pertusa from Asia. In the present study, we extracted DNA from the type specimen of U. australis housed in the Swedish Museum of Natural History (S) and obtained DNA sequences of the chloroplast rbcL gene and the nuclear rDNA ITS2 region. Our results show that U. australis and U. pertusa are genetically virtually identical, confirming that U. pertusa is a synonym of U. australis. This suggests that the introduction of U. australis to Australia occurred by the middle of the 19th century, when the type was collected and before there was a direct shipping route between Japan and Australia. We speculate that the introduction of U. australis to Australia occurred as a secondary introduction from non‐indigenous populations in northeastern Asia, but not directly from Japan.  相似文献   
100.
In response to the over‐representation of Australian Indigenous women in the criminal justice system, culturally relevant and gender‐specific bail programs operate in several Queensland Indigenous sentencing courts or Murri Courts. Queensland Murri Courts are a specialist criminal law practice, which includes Elders and respected persons of Community Justice Groups in the sentencing process of Indigenous peoples. This paper explores the role of one gender‐specific bail program, Women's Yarning or Talking Circles, in one Southeast Queensland Murri Court. Women's Yarning Circles aspire to create an Indigenous‐centred space outside of court proceedings where defendants and Community Justice Group members of the same gender can build a rapport. Gender‐specific bail programs aim to recognise the intricacies of an Indigenous woman's intersectional identity and the diverse needs of each defendant that comes before the Murri Court.  相似文献   
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