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71.
Michela Candelma Luisa Dalla Valle Sabrina Colella Alberto Santojanni Oliana Carnevali 《Fish physiology and biochemistry》2018,44(3):895-910
Teleosts have many spawning strategies and the hormonal control of gametogenesis is not well defined among the species or even, between sexes. To increase the knowledge of gonadotropin hormones, we studied the trend by gene expression of gonadotropin receptors in the follicles and testis at different maturity stages in the European hake (Merluccius merluccius), a multiple-spawning species. With this aim, fshr and lhr were sequenced, characterized, and their gene expression was quantified in oocytes and in testes at different maturity stages. The deduced amino acid sequences were used to phylogenetic studies and evidenced that both receptors are phylogenetically closed to other gadoid species. The gene expression of both receptors was poorly expressed in primary follicles, increased in vitellogenic follicles and to later decrease in hydrated oocytes. In testis, highest levels of lhr were detected during spermiation, while levels of fshr were constant. For the first time, a histological analysis was performed in European hake testes showing an unrestricted lobular testis. To better elucidate the mechanisms involved in the oogenesis of the European hake, the expression of estrogen receptor and cyp19a was also investigated displaying high levels in all classes of follicles. All these data allow to increase the knowledge on reproductive physiology of an important socioeconomical species and it seeks to shed more light on the role of the receptors here studied during gametogenesis of multiple-spawning fish. 相似文献
72.
White yam (Dioscorea rotundata) is an important tuber crop of West Africa and the Caribbean, and one of the key limiting factors in its production is the availability of good quality planting material. The Adaptive Yam Minisett Technique (AYMT) was designed to help overcome this constraint. The paper presents an analysis of agronomic and economic data collected across four years (2013 to 2016) of AYMT plots planted in two areas within the middle-belt of Nigeria. Of the 136 plots that were established, 11% were lost to flooding and damage from Fulani cattle. Mean yield was 13.16 t/ha, 17,747 tubers/ha and the mean tuber weight was 0.73 kg. Plot yield declined with an increase in planting time, while plots owned by female farmers were on average planted later than those owned by their male counterparts; this helps explain the effect of gender noted in a previous study. Differences in yield were also noted between the two areas, which could also partly be explained by differences in planting time. The plots were profitable, with a mean cost over the four years of Naira 915,196/ha, revenue of Naira 3,197,786/ha and gross margin of Naira 2,282,591/ha (equivalent to US$4,039, US$14,319 and US$10,280 respectively). The main factor influencing costs and revenue was year, with no effect of gender. There is a need for more research on planting time in AYMT and how it interacts with factors, such as yam variety. 相似文献
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Granum Espen Pérez-Bueno María Luisa Calderón Claudia E. Ramos Cayo de Vicente Antonio Cazorla Francisco M. Barón Matilde 《European journal of plant pathology / European Foundation for Plant Pathology》2015,142(3):625-632
European Journal of Plant Pathology - One of the most important soilborne diseases affecting avocado (Persea americana Mill.) crops is white root rot, caused by the fungus Rosellinia necatrix. In... 相似文献
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Isidro A. Prez M. Luisa Snchez M. ngeles García Beatriz de Torre 《Agricultural and Forest Meteorology》2009,149(10):1686-1692
CO2 is one of the most important gases linked to climate change. However, its ambient concentrations in a clean atmosphere have scarcely been investigated. In this paper a close relationship between CO2 concentrations and meteorological variables was proposed to establish atmospheric conditions linked to high CO2 values. A detailed 3-year campaign was carried out in a rural area with a CO2 continuous analyser and a RASS sodar for meteorological variables. Daily and yearly CO2 cycles were obtained. In addition, semi-hourly medians and quartiles were fitted to straight lines during the night time and daily maxima and minima were parameterised by means of a second order cylindrical model. Six meteorological variables were considered: wind speed, wind direction and temperature at one level and differences between them at two levels. Intervals were proposed from the highest CO2 concentrations during the night to build up a binary system of 64 meteorological classes. Analysis of both CO2 medians and meteorological classes enabled simplification of the system to four groups. The first group, characterised by high temperatures and drainage flow, was associated with detrended median concentrations above 15 ppm. Two groups of moderate concentrations were linked to thermal inversions and no prevailing wind directions. The final group corresponded to low concentrations associated with less than three meteorological variables with values linked to high concentrations. Only high directional shear and low wind speed were relevant in this group. This 4-group system was successfully used with the whole dataset. 相似文献
78.
Oliveiro Caetano de Freitas Neto Sonia Luisa Silva Lages Adriano Oliveira Torres Carrasco Angelo Berchieri Junior 《Tropical animal health and production》2009,41(8):1607-1614
We analyzed ostriches from an equipped farm located in the Brazilian southeast region for the presence of Salmonella spp. This bacterium was investigated in 80 samples of ostrich droppings, 90 eggs, 30 samples of feed and 30 samples of droppings
from rodents. Additionally, at slaughter-house this bacterium was investigated in droppings, caecal content, spleen, liver
and carcasses from 90 slaughtered ostriches from the studied farm. Also, blood serum of those animals were harvested and submitted
to serum plate agglutination using commercial Salmonella Pullorum antigen. No Salmonella spp. was detected in any eggs, caecal content, liver, spleen, carcass and droppings from ostriches and rodents. However,
Salmonella Javiana and Salmonella enterica subsp. enterica 4, 12: i:- were isolated from some samples of feed. The serologic test was negative for all samples. Good sanitary farming
management and the application of HACCP principles and GMP during the slaughtering process could explain the absence of Salmonella spp. in the tested samples. 相似文献
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80.
Trevor Daly Marvin A. Jiwan Nora M. O’Brien S. Aisling Aherne 《Plant foods for human nutrition (Dordrecht, Netherlands)》2010,65(2):164-169
Herbs are a rich source of bioactive phytochemicals such as carotenoids, which are known to exert various positive biological
effects. However, there is very limited information in the literature regarding the content and bioavailability of carotenoids
from commonly consumed herbs. Therefore, the objectives of the present study were first, to determine the carotenoid content
of eight herbs namely basil (Ocimum basilicum), coriander (Coriandrum sativum), dill (Anethum graveolens), mint (Metha L.),
parsley (Petroselinum crispum), rosemary (Rosmarinus officinalis), sage (Salvia officinalis), and tarragon (Artemisia dracunculus
L.); and second, to assess carotenoid bioaccessibility from these herbs using a simulated human in vitro digestion model.
Carotenoid bioaccessibility is defined as the amount of carotenoids transferred to micelles after digestion when compared
with the original amount present in the food. The content of individual carotenoids varied significantly among the herbs tested.
Carotenoid bioaccessibility varied from 0 to 42.8%. Basil and coriander, and their respective micelles, contained the highest
levels of β-carotene, β-cryptoxanthin, and lutein + zeaxanthin. Our findings show that herbs are rich sources of carotenoids
and that these foods can significantly contribute to the intake of bioaccessible carotenoids. 相似文献