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81.
Dao Ha Viet Takata Yoshinobu Omura Takuo Sato Shigeru Fukuyo Yasuwo Kodama Masaaki 《Fisheries Science》2009,75(2):507-512
Previously we reported that a significant level of domoic acid, a causative toxin for amnesic shellfish poisoning, was detected
in bivalves belonging to a genus Spondylus from various tropical Asian countries. These findings indicate that causative plankton species for domoic acid widely distribute
in these areas. In the present study, we monitored seasonal change of domoic acid level of Spondylus versicolor in association with that of plankton samples in Nha Phu Bay, Khanh Hoa, Vietnam from December 2004 to October 2005. The toxicity
of S. versicolor showed distinct seasonal variation. During the period when domoic acid level of S. versicolor was increasing, a significant level of domoic acid was detected in the plankton samples, showing the correlation between
these two parameters. These findings show that plankton causative for domoic acid occurred in the bay, and S. versicolor accumulate domoic acid during a bloom of the toxic plankton by food web transfer. 相似文献
82.
Nguyen Thi Hue Linh Setsuko Nagai Noriko Nagasaka Seika Okane Yousuke Taoka 《Fisheries Science》2018,84(6):1051-1062
This study aimed to evaluate the effect of Lactococcus lactis K-C2 on the growth performance, microbial diversity, and release of free amino acids in the intestinal tract and the edible parts of young amberjack, Seriola dumerili. Fish were fed a diet with or without strain K-C2 (2?×?1010 cfu/g feed) for 25 days. The results indicated that the growth performance of fish in the treated group was significantly higher than those in the control group (p?<?0.05). The amount of five amino acids (aspartate, sarcosine, taurine, alanine, and arginine) in the gut content and 13 of 21 amino acids in the edible parts of fish in the treated group were significantly higher (p?<?0.05) than those in the control group. Sphingomonas, Propionibacterium, and Mycobacterium were observed in gut microflora of fish in both the control and treated groups. Staphylococcus and Kocuria were detected in one sample from the control and treated groups; Acinetobacter and Acidobacteria were found in one sample from the control group. L. lactis was only found in one sample in the treated group. In conclusion, the dietary administration of probiotic L. lactis stimulated growth, reduced feed consumption, and improved the nutritional value of cultured amberjack. 相似文献
83.
The potential of informal institutions for marine fisheries management—A case study of a coastal commune in Vietnam 下载免费PDF全文
Dang Bach Nguyen Salim Momtaz Nhung Thi Hong Pham 《Fisheries Management and Ecology》2018,25(4):275-286
The potential of informal institutions for sustainable management of marine fisheries was examined. The study is based on both primary data collected through two group discussions and interviews and secondary information, including material related to fishing gear operation and whale worship. It shows that informal institutions, including fisher groups, fishing community norms, fisher's knowledge and whale worship have potential to strengthen institutional, ecological, social and community aspects of sustainable fisheries development. Although these informal institutions are not able to fix completely all the problems faced by formal institutions, they are able to complement and consolidate formal institutions to manage marine fisheries effectively. The findings of this study suggest it is imperative that formal institutions should be improved simultaneously with informal institutions to enhance current management for sustainable marine fisheries development. 相似文献
84.
85.
Thi Thu Hang Ngo Hossein Azadi Huu Cuong Tran Philippe Lebailly 《Aquaculture International》2018,26(2):451-468
Clam farmers have experienced different types of risks that have been further exacerbated by the rapid expansion of clam farming areas, increased growing densities, and increased market difficulties in recent years in the Thaibinh Province of Vietnam. Most farmers have been seriously affected by production risk, market risk, and financial risk, while a number of others have met with success in almost all of their clam-raising cycles. This study applied a differentiating comparative analysis method and multiple discriminant analysis method to discuss the differences in risk management strategies between and among clam farming households and the impacts of those differences on their success/failure rates. In general, the tactics are related to increase in farm size, the application of technical innovations, diversifying livelihood activities, and accessing secure financial sources all provided better conditions for clam growth, diminished losses, and led to speedier recovery from shocks. To support farmers in managing risks, several government interventions are needed: (1) better re-zoning of clam farming areas in parallel with an increase in the farm size of each household, (2) promoting sustainable linkages between the farmers and the formal financial market and output market, and (3) investing more funding into research and extension related to sustainable clam farming practices and to the improvement of farmers’ skills in cooperative works and management. 相似文献
86.
87.
Pil Birkefeldt Møller Pedersen Kasper Hansen Do Thi Thanh Houng Mark Bayley Tobias Wang 《Aquaculture Research》2014,45(3):427-438
The Asian swamp eel Monopterus albus is normally considered a freshwater species, but can also occasionally be found in brackish water. It is an obligate air‐breather with highly reduced gills, making its osmoregulation physiology interesting because the gills normally represent the primary site of osmoregulation in teleosts. Being a popular fish for human consumption, the swamp eel is cultured extensively in freshwater ponds in the Mekong Delta of Vietnam. However, very little is known about its salinity tolerance, which is becoming topical due to the increasing salt‐water intrusions into tropical deltas. We therefore studied how increased salinity affects survival, growth, blood pressure, heart rate, blood osmolality and plasma ions. All eels survived prolonged exposure to 5 and 10 g L?1, although plasma osmolality increased significantly at 10 g L?1. Further elevation to 15 and 20 g L?1 was associated with significantly elevated mortality, with a corresponding increase in plasma osmolality and ion con‐centrations. Our results show that swamp eels thrive in 0–10 g L?1 with an optimum growth between 0 and 9 g L?1, indicating that utilization of low saline brackish waters for aquaculture is possible. 相似文献
88.
Mass selection for small‐sized cysts in Artemia franciscana produced in Vinh Chau salt ponds,Vietnam
Nguyen Thi Hong Van Nguyen Van Hoa Peter Bossier Patrick Sorgeloos Gilbert Van Stappen 《Aquaculture Research》2014,45(10):1591-1599
Unidirectional mass truncation selection for small‐sized cysts was carried out on brine shrimp (Artemia franciscana Kellogg 1906), Vinh Chau strain, Vietnam, through cyst sieving and then culturing the selected individuals (<5% of the population) under field and laboratory conditions over two successive generations (F1 and F2). The results showed that at both culture scales, the cyst size of the selected line was smaller (P < 0.05) compared with the control (non‐selected) line, illustrating that there was a response to selection. The cyst size decreased about 3% per generation and the accumulated gain on the target trait was in the range 5.82–6.07% at the end of the selection process compared with the base population. The realized heritability estimation (h2) for cyst size was 0.23 ± 0.06 and 0.74 ± 0.19 in the field trials and 0.34 and 0.51 in the laboratory test for the F1 and F2 generation respectively. The variations found between the respective trials may be explained as the result of environmental interaction with the selection process, but the results show that a selection program for small‐sized cysts in Artemia by mass selection is possible. 相似文献
89.
Thai Khanh Phong Dang Thi Tuyet Nhung Takashi Motobayashi Dang Quoc Thuyet Hirozumi Watanabe 《Water, air, and soil pollution》2009,202(1-4):3-12
The fate and transport of tricyclazole and imidacloprid in paddy plots after nursery-box application was monitored. Water and surface soil samples were collected over a period of 35 days. Rates of dissipation from paddy waters and soils were also measured. Dissipation of the two pesticides from paddy water can be described by first-order kinetics. In the soil, only the dissipation of imidacloprid fitted to the simple first-order kinetics, whereas tricyclazole concentrations fluctuated until the end of the monitoring period. Mean half-life (DT50) values for tricyclazole were 11.8 and 305 days, respectively, in paddy water and surface soil. The corresponding values of imidacloprid were 2.0 and 12.5 days, respectively, in water and in surface soil. Less than 0.9% of tricyclazole and 0.1% of imidacloprid were lost through runoff during the monitoring period even under 6.3 cm of rainfall. The pesticide formulation seemed to affect the environmental fate of these pesticides when these results were compared to those of other studies. 相似文献
90.
Tran Thi Thu Hong Thai Thi Thuy Volkmar Passoth Jan Erik Lindberg 《Livestock Science》2009,125(2-3):232-237
Gut environment and microflora, digestibility, and performance were studied in weaned piglets in Central Vietnam fed a dry control diet (CO), a naturally fermented liquid diet (FE), and a liquid diet with inclusion of rice distiller's residue (RDR). Digesta samples were collected at the start (day 0) and at the end of experiment (day 42). Diet FE had a lower pH than diet RDR, contained more organic acids, had the lowest counts of E. coli and total coliforms (P < 0.05), and the highest counts of lactic acid bacteria (LAB) (P < 0.05). Piglets fed diets FE and RDR had lower pH (P < 0.05), and higher concentrations of organic acids in the stomach, ileum and mid-colon (P < 0.05) than piglets fed diet CO. Counts of LAB in stomach and ileum were higher in animals fed diets FE and RDR than CO (P < 0.05), while the number of E. coli and total coliforms along the gastrointestinal tract was reduced. The ileal digestibility of crude protein and organic matter was improved in piglets fed diet RDR (P < 0.05) compared with piglets fed diet CO. Piglets fed diet RDR had a higher weight gain (P < 0.05) and a better feed utilization (P < 0.05) than piglets fed the other diets. The present findings support the contention that fermented diets and/or fermented feedstuffs can be used for dietary manipulation to improve gut health and animal performance. 相似文献