全文获取类型
收费全文 | 402篇 |
免费 | 10篇 |
专业分类
林业 | 28篇 |
农学 | 6篇 |
43篇 | |
综合类 | 8篇 |
农作物 | 12篇 |
水产渔业 | 32篇 |
畜牧兽医 | 269篇 |
园艺 | 1篇 |
植物保护 | 13篇 |
出版年
2022年 | 25篇 |
2021年 | 30篇 |
2020年 | 4篇 |
2019年 | 6篇 |
2018年 | 11篇 |
2017年 | 4篇 |
2016年 | 13篇 |
2015年 | 22篇 |
2014年 | 34篇 |
2013年 | 24篇 |
2012年 | 22篇 |
2011年 | 33篇 |
2010年 | 14篇 |
2009年 | 11篇 |
2008年 | 24篇 |
2007年 | 29篇 |
2006年 | 23篇 |
2005年 | 27篇 |
2004年 | 21篇 |
2003年 | 8篇 |
2002年 | 14篇 |
2001年 | 4篇 |
2000年 | 2篇 |
1999年 | 2篇 |
1998年 | 1篇 |
1997年 | 2篇 |
1993年 | 1篇 |
1984年 | 1篇 |
排序方式: 共有412条查询结果,搜索用时 281 毫秒
11.
The relationship between commuting distances and where people work has been studied for urban contexts in both developed countries and developing countries. However, few studies have examined the situation in rural areas, and none look at commuting distances to non‐farm workplaces in rural areas of developing countries. This paper investigates how commuting distance, and thus accessibility, to local non‐farm work influences non‐farm employment and out‐migration from rural villages in Northeast Thailand. The main issues examined are: (i) the distance that rural residents travel to work in local non‐farm jobs; and (ii) the influence that local non‐farm employment has on the number of outmigrants from rural villages. The study finds: (i) distance between villages and non‐farm work sites impact the number of villagers who are employed in regular wage work; (ii) beyond 20 km villagers are less likely to travel to non‐farm employment using their own means of transportation; and (iii) employment in regular wage work decreases outmigration. The findings from this study contribute to the debates over the drivers of rural out‐migration, rural livelihood changes, and agrarian changes that are taking place in Southeast Asia. 相似文献
12.
Nguyen Vu SON James Kenn CHAMBERS Makoto NAKATA Yasutsugu MIWA Hiroyuki NAKAYAMA Kazuyuki UCHIDA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(2):208
This report described the histopathological and immunohistochemical features of cutaneous mast cell tumor (MCT) in six hedgehogs. The hedgehogs presented single cutaneous mass with ulcer and crusting. Histologically, the neoplastic lesions were characterized by the proliferation of well-differentiated mast cells (3 cases), and atypical mast cells (3 cases) with one atypical histiocytic morphology. Immunohistochemically, tumor cells were positive for KIT and mast cell tryptase, and were negative for Iba-1. In well-differentiated MCT, all patients were clinically improved and survived more than 365 days after surgical excision, whereas an atypical histiocytic MCT showed aggressive behavior with re-recurrence, and the animal died 115 days after surgery. These findings suggest that, compatible with other animals, well-differentiated MCT has a better prognosis in hedgehogs. 相似文献
13.
Michiru Akamatsu Ryosuke Hirozumi Yuko Cho Yuta Kudo Keiichi Konoki Yasukatsu Oshima Mari Yotsu-Yamashita 《Marine drugs》2022,20(3)
Saxitoxin and its analogues, paralytic shellfish toxins (PSTs), are potent and specific voltage-gated sodium channel blockers. These toxins are produced by some species of freshwater cyanobacteria and marine dinoflagellates. We previously identified several biosynthetic intermediates of PSTs, as well as new analogues, from such organisms and proposed the biosynthetic and metabolic pathways of PSTs. In this study, 12β-deoxygonyautoxin 5 (12α-gonyautoxinol 5 = gonyautoxin 5-12(R)-ol) was identified in the freshwater cyanobacterium, Dolichospermum circinale (TA04), and 12β-deoxysaxitoxin (12α-saxitoxinol = saxitoxin-12(R)-ol) was identified in the same cyanobacterium and in the marine dinoflagellate Alexandrium pacificum (Group IV) (120518KureAC) for the first time from natural sources. The authentic standards of these compounds and 12α-deoxygonyautoxin 5 (12β-gonyautoxinol 5 = gonyautoxin 5-12(S)-ol) were prepared by chemical derivatization from the major PSTs, C1/C2, produced in D. circinale (TA04). These standards were used to identify the deoxy analogues by comparing the retention times and MS/MS spectra using high-resolution LC-MS/MS. Biosynthetic or metabolic pathways for these analogues have also been proposed based on their structures. The identification of these compounds supports the α-oriented stereoselective oxidation at C12 in the biosynthetic pathway towards PSTs. 相似文献
14.
Uchida Y Ike K Kurotaki T Takeshi M Imai S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(3):401-403
Djungarian hamsters were examined for the susceptibility to Neospora caninum infection. After 29 Djungarian hamsters were intraperitoneally inoculated with 5 x 10(6) N. caninum tachyzoites of JPA1 strain, some animals showed symptoms such as ataxia, and many tissue cysts were detected in the brain and a cyst in the muscular tunics of stomach. Especially, more than 100 cysts per head were observed after 5 weeks post inoculation. It is suggested that the Djungarian hamster is a model useful to examine neosporosis. 相似文献
15.
Kawakami E Morita Y Hori T Tsutsui T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(7):543-549
Cross sections of the testes and the caput, corpus and cauda epididymides removed from 12 dogs were stamped on glass slides, and the sperm on the slides were stained with 6 different FITC-lectins (Con A, DBA, PNA, PSA, SBA, and WGA) to examine the characteristics of the surface glycoproteins (GPs) on canine epididymal sperm. The corpus epididymal sperm were washed three times by centrifugation, and their lectin-binding characteristics were investigated. The washed sperm from the corpus and cauda epididymides were incubated for 24 hr, and the fertilizing capacity of the sperm was evaluated by calculating the percentages of actively motile sperm (%MO), hyperactivated sperm (%HA), and acrosome-reacted sperm (%AR), and the number of canine zona-pellucida (ZP)-binding sperm. The testicular sperm did not stain with SBA lectin, but the SBA lectin fluorescence was observed on the surface of the entire heads of the caput epididymal sperm. Although all of the entire heads or acrosomal regions of the corpus epididymal sperm stained with all 6 FITC-lectins, the heads and acrosomal regions of the cauda epididymal sperm did not stain with DBA or SBA lectins. Washing the sperm from the corpus epididymis resulted in loss of the fluorescence of the FITC-DBA and -SBA lectins. The mean %MO, %HA, %AR, and ZP-binding number of the cauda epididymal sperm after 24 hr of incubation were higher than the values for the corpus epididymal sperm. All of the mean values for the washed sperm from the corpus and cauda epididymides were higher than the values for the unwashed sperm from the corpus and cauda, and with the exception of %AR, the values from the washed sperm from the corpus epididymis were significantly higher (P<0.05, 0.01). The results indicate that DBA- and SBA-lectin-binding GPs on the surface of canine epididymal sperm are associated with the fertilizing capacity and may be decapacitation factors. 相似文献
16.
Kenji UCHIDA Masahiro HIRATA Hidemasa MOTOSHIMA Tadasu URASHIMA Ikichi ARAI 《Animal Science Journal》2007,78(6):650-658
The traditional fermented dairy products were collected from three nomadic families in Donto‐Govi prefecture in Mongolia (central Mongolia), and those microbiota were analyzed. These samples consist three of ‘airag’, two of ‘tarag’, two of ‘isgelen tarag’ and ‘qoormog’, and some cheeses. In airag, Lactobacillus (L.) helveticus, L. kefiri, and Saccharomyces (S.) dairensis were common, and L. paracasei, L. plantarum, L. farciminis, S. cerevisiae, Issachenkia (I.) orientalis, Kluyveromyces (K.) wickerhamii were also found. In tarag, isgelen tarag and qoormog, L. helveticus, L. kefiri, L. fermentum, L. paracasei and L. acetotolerance were found. L. delbrueckii subsp. bulgaricus was also found in one tarag and one qoormog samples. Randomly amplified polymorphic DNA (RAPD) analysis showed that there were diversity in each L. helveticus family and products, and there were common strains found in airag and tarag in the same family. 相似文献
17.
Kaoru Hanada Fumiyoshi Fukumoto Manabu Kusunoki Mitsuro Kameya-Iwaki Yuko Tanaka Toru Iwanami 《Journal of General Plant Pathology》2006,72(6):383-386
An undescribed spherical virus ca. 30 nm in diameter was isolated from gladiolus (Gladiolus spp.) plants in Japan. The virus had a moderate host range within eight families. Purified virus preparations contained two
large RNA components and one coat protein with mobility similar to Cycas necrotic stunt virus (CNSV) from cycas (Cycas revolute). The virus was serologically closely related to CNSV. Its nucleotide sequence of the coat protein gene had 89% common identity
with that of CNSV. These results indicated that the virus isolated from gladiolus is a new strain of CNSV.
The nucleotide sequence data reported are available in the DDBJ/EMBL/Gen Bank databases under the accession number AB237656. 相似文献
18.
In a previous study, it was found that there are sex differences in goats with respect to the levels of cortisol secretion induced by transportation stress. We also found that treatment of castrated male goats with dihydrotestosterone (DHT) suppressed the increase in plasma cortisol concentration following transportation, but did not suppress the secretion of adrenocorticotropic hormone (ACTH). This suggests that androgen might block ACTH ‐ induced cortisol secretion. In order to examine this hypothesis, the effects of androgen on ACTH‐induced cortisol secretion in goats were investigated. First, castrated male goats were treated with testosterone (T), DHT or cholesterol (cho) for 21–25 days. Cho was used as a control for T and DHT treatment. Then, plasma cortisol concentrations were compared among the hormonal treatments after ACTH injection. Subsequently, the distribution of androgen receptors in the caprine adrenal gland was investigated. There were no differences in the basal cortisol concentrations among the hormonal treatments. However, plasma cortisol concentrations after ACTH injection were significantly lower in T ‐ and DHT ‐ treated goats than in cho ‐ treated goats. Androgen receptors were present in 60% of the cells in the zonae fasciculata and reticularis of the adrenal cortex, the regions that secrete glucocorticoids. These results suggest that androgen may act directly on the adrenal cortex to suppress cortisol secretion induced by ACTH. 相似文献
19.
Toshiyuki Usami Shu Ishigaki Hiroko Takashina Yuko Matsubara Yoshimiki Amemiya 《Journal of General Plant Pathology》2007,73(2):89-95
Japanese isolates of Verticillium dahliae, a causal agent of wilt disease in many plants, are classifiable into pathotypes based on their pathogenicity. Because these
pathotypes are morphologically indistinguishable, establishing a rapid identification method is very important for the control
of this pathogen in Japan. For cloning DNA fragments that are useful for identification and specific detection of V. dahliae pathotypes, we performed random amplified polymorphic DNA (RAPD) analyses using various isolates. One polymerase chain reaction
(PCR) product, E10-U48, was specific to isolates pathogenic to sweet pepper. The other product, B68-TV, was specific to race
1 of isolates pathogenic to tomato. The specificity of these sequences was confirmed by genomic Southern hybridization. Further
analyses revealed that the region peripheral to B68-TV obtained from the genomic DNA library includes the sequence specific
to all isolates pathogenic to tomato (races 1 and 2). Moreover, sequence tagged site (STS) primers designed from B68-TV and
its peripheral region showed race-specific and pathotype-specific amplification in a PCR assay. The probes and primers obtained
in this study are likely to be useful tools for the identification and specific detection of pathotypes and races of V. dahliae.
The nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under accession number AB095266. 相似文献
20.