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91.
This research note offers a brief summary of recent cartographic work in the province of Lao Cai in northern Vietnam, with a specific focus on the districts of Sa Pa and Bac Ha. By providing a representation of topography in digital format, which enables a connection between demographic and physical variables, the long term aim is to illustrate the relationship between ethnicity and topography. 相似文献
92.
Tour guides as tourist products in Dalat,Vietnam: Exploring market freedoms in a communist state 下载免费PDF全文
This paper investigates how tour guides position themselves in Vietnam's transition from a command economy to market socialism. The case study of the Dalat Easy Riders motorcycle guides demonstrates that tour guides take advantage of, personify and contribute to the economic, political and social transitions in the country. Relatedly, we argue that Vietnam's transition (known as ??i m?i) is a key component of the Easy Riders' promotional narratives. In sum, we analyse how tour guides become tourist products in a transitional society. 相似文献
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为查明越南松树枯死的原因,对越南南部的林同省,中部的承天-顺化省,北部的广宁省的思茅松、马尾松和南亚松枯死症状和原因进行了调查,分别从枯死、濒死、健康松树木质部中抽取52份样品,用于线虫分离镜检。调查发现松树在感病后,树冠部分针叶失去光泽,逐渐褪绿变黄,进而褐红干枯,最后整个树冠变为褐色或红褐色,全株枯死,针叶下垂且当年不落;随着病程的发展,松脂分泌逐渐减少,直至停止;树干上有天牛产卵刻槽,死亡的松树上有天牛的羽化孔。在抽取的松树样品中分离鉴定到了泰国伞滑刃线虫(Bursaphelenchus thailandae BrasschBrassch-Bidasak,2002),为病原的确定和防治工作提供初步的依据。 相似文献
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Land-use impacts on surface runoff and soil detachment within agricultural sloping lands in Northern Vietnam 总被引:1,自引:0,他引:1
P. Podwojewski D. Orange P. Jouquet C. Valentin Van Thiet Nguyen J.L. Janeau Duc Toan Tran 《CATENA》2008,74(2):109-118
Two consecutive years of investigation on soil surface features, surface runoff and soil detachment within 1-m2 microplots on 40% slope highlighted the effects of land-use change, vegetation cover and biological activity on the water pathways in Northern Vietnam. Three replicate plots were set up on each of five land-uses: cassava (CAS), grass fodder of Bracharia ruziziensis (BRA), a 3-year old fallow (FAL), tree stands of Acacia mangium and Venicia montana (FOR), and a fallow with regrowth of Eucalyptus regularly cut (EUC). The second year, two of the microplots under FAL and EUC were treated with herbicide (FALh, EUCh), one of them was burnt (FALh+b, EUCh+b). The highest yearly surface runoff coefficient of 16%, and soil detachment rate of 700 g m− 2 yr− 1 in average with a maximum of 1305 g m− 2 yr− 1 have been recorded under CAS. On FALh and FALh+b, runoff ratios were 8.7 and 13.5%, respectively and detachment rates were 86 and 389 g m− 2. On FAL and BRA the yearly runoff ratio varied from 5.9 to 9.8% but the detachment rate was limited at 24 to 35 g m− 2. FOR and EUC annual runoff was ≤ 3.1% and annual soil detachment ≤ 71 g m− 2. These values were very low compared to the values reported on steep slopes in Laos within similar climate and vegetation cover.The runoff and detachment rates underlined the importance of rainfall intensities, soil physical properties, soil surface features, soil vegetation cover and biological activity. The annual surface runoff was highly correlated to the soil surface crusting. CAS and BRA plots were prone to crusting especially after weeding at the onset of the rainy season, when the soil surface was still uncovered. Soil bioturbation (earthworm casting activity) was the second factor that explains local variation of surface runoff and soil detachment. The continuous production of earthworms casts on soil surface, especially on FOR and EUC microplots, induced a marked surface roughness and reduced the surface runoff. The production of casts was very limited in FAL and completely absent in CAS microplots. So it is evident that our results confirm the deleterious effects of cassava on soil and water conservation. 相似文献
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Non‐Typhoidal Salmonella Colonization in Chickens and Humans in the Mekong Delta of Vietnam 下载免费PDF全文
N. V. Trung J. J. Carrique‐Mas N. H. Nghia L. T. P. Tu H. H. Mai H. T. Tuyen J. Campbell N. T. Nhung H. N. Nhung P. V. Minh T. T. B. Chieu T. Q. Hieu N. T. N. Mai S. Baker J. A. Wagenaar N. T. Hoa C. Schultsz 《Zoonoses and public health》2017,64(2):94-99
Salmonellosis is a public health concern in both the developed and developing countries. Although the majority of human non‐typhoidal Salmonella enterica (NTS) cases are the result of foodborne infections or person‐to‐person transmission, NTS infections may also be acquired by environmental and occupational exposure to animals. While a considerable number of studies have investigated the presence of NTS in farm animals and meat/carcasses, very few studies have investigated the risk of NTS colonization in humans as a result of direct animal exposure. We investigated asymptomatic NTS colonization in 204 backyard chicken farms, 204 farmers and 306 matched individuals not exposed to chicken farming, in southern Vietnam. Pooled chicken faeces, collected using boot or handheld swabs on backyard chicken farms, and rectal swabs from human participants were tested. NTS colonization prevalence was 45.6%, 4.4% and 2.6% for chicken farms, farmers and unexposed individuals, respectively. Our study observed a higher prevalence of NTS colonization among chicken farmers (4.4%) compared with age‐, sex‐ and location‐ matched rural and urban individuals not exposed to chickens (2.9% and 2.0%). A total of 164 chicken NTS strains and 17 human NTS strains were isolated, and 28 serovars were identified. Salmonella Weltevreden was the predominant serovar in both chickens and humans. NTS isolates showed resistance (20–40%) against tetracycline, chloramphenicol, sulfamethoxazole‐trimethoprim and ampicillin. Our study reflects the epidemiology of NTS colonization in chickens and humans in the Mekong delta of Vietnam and emphasizes the need of larger, preferably longitudinal studies to study the transmission dynamics of NTS between and within animal and human host populations. 相似文献
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Dung Thi LE Son Vu NGUYEN Mari OKAMOTO Nanako YAMASHITA-KAWANISHI Tung Duy DAO Vuong Nghia BUI Haruko OGAWA Kunitoshi IMAI Takeshi HAGA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(8):1273
The detection of bovine foamy virus (BFV) in Vietnamese cattle was performed using conventional PCR targeting pol and gag genes. Out of 243 tested samples, ten (4.1%) and eight (3.3%) samples were positive for BFV gag and pol DNA, respectively. The prevalence of bovine leukemia virus (BLV) estimated by detection of proviral DNA using nested PCR targeting env gene was 26.7% (65/243). The results of nucleotide sequence alignment and the phylogenetic analysis suggested that Vietnamese BFV strains showed high homology to isolates belonging to either European or non-European clades. There was no significant correlation between BLV and BFV. This study provides information regarding BFV infection and confirms the existence of two BFV clades among Vietnamese cattle for the first time. 相似文献