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排序方式: 共有193条查询结果,搜索用时 46 毫秒
51.
Cibele Soares Pontes Maria de Fatima Arruda Alexandre Augusto de Lara Menezes & Patrícia Pereira de Lima 《Aquaculture Research》2006,37(10):1001-1006
Lack of information on the daily activity patterns of Litopenaeus vannamei (Boone 1931) might result in inadequate feed management strategies in shrimp farms. In order to provide information to improve feed management in shrimp farms, the daily activity of juvenile shrimp reared in glass aquaria was studied, using L. vannamei (7.57±1.01 g), equivalent to 33 shrimp m?2. Thirty‐two shrimp were observed, half in light and half in dark phase, over 280 h in 15 min h?1 windows. Feed was provided once a day, at 10% of tank biomass. Swimming, exploration of substrate, inactivity and cleaning were recorded through instantaneous focal sampling. During the dark phase, swimming was predominant and alternated with exploration. In the light phase, inactivity was predominant, and again alternated with exploration. Cleaning occurred evenly in both the light and the dark. Substrate exploration, which characterizes the search for food, occurred in both dark and light phases, with a most intense peak 7 h after light phase onset, indicating this as the optimal feed offer. 相似文献
52.
Faruk Bogunić Sonja Siljak-Yakovlev Edina Muratović Fatima Pustahija Safer Medjedović 《Annals of Forest Science》2011,68(1):179-187
• Introduction
The most common representatives of the European mountain pine complex (Pinus mugo s.l.) are P. mugo s.s. and Pinus uncinata. 相似文献53.
G Sarwar H G Botting R W Peace 《Journal of the Association of Official Analytical Chemists》1988,71(6):1172-1175
The amino acid analysis method using precolumn phenylisothiocyanate (PITC) derivatization and liquid chromatography was modified for accurate determination of methionine (as methionine sulfone), cysteine/cystine (as cysteic acid), and all other amino acids, except tryptophan, in hydrolyzed samples of foods and feces. A simple liquid chromatographic method (requiring no derivatization) for the determination of tryptophan in alkaline hydrolysates of foods and feces was also developed. Separation of all amino acids by liquid chromatography was completed in 12 min compared with 60-90 min by ion-exchange chromatography. Variation expressed as coefficients of variation (CV) for the determination of most amino acids in the food and feces samples was not more than 4%, which compared favorably with the reproducibility of ion-exchange methods. Data for amino acids and recoveries of amino acid nitrogen obtained by liquid chromatographic methods were also similar to those obtained by conventional ion-exchange procedures. 相似文献
54.
Fatima Tamtam Barbara Le Bot Tuc Dinh Sophie Mompelat Joelle Eurin Marc Chevreuil Philippe Bonté Jean-Marie Mouchel Sophie Ayrault 《Journal of Soils and Sediments》2011,11(5):852-859
Purpose
Even though sediments may represent a reservoir for antimicrobial agents, little is known about the persistence of these molecules over time or their accumulation. In this study, six antimicrobial agents, oxolinic acid, flumequine, nalidixic acid, norfloxacin, sulphamethoxazole and trimethoprim, were investigated in a sediment core from the Seine River. This work aimed to (1) measure antimicrobial agent contamination levels in the sediment and identify their origins, (2) obtain information on the persistence of these compounds in sediment over long periods (>4 years) and (3) show the existence of a historical record in sediment of river contamination by antimicrobial agents. 相似文献55.
56.
Abubakar M Rajput ZI Arshed MJ Sarwar G Ali Q 《Tropical animal health and production》2011,43(4):745-747
An outbreak resulting in mortality in Sindh Ibex (Capra aegagrus blythi) was investigated. There was a history of about 36 deaths (both young and adult) during the period of 1 month. Disease appeared
in a generalized form, affecting the respiratory and digestive systems. Major lesions were respiratory distress, pustules
on and in the mouth, ocular–nasal discharges, and severe diarrhea. The most significant lesion was the oculonasal discharges
and diarrhea. Deaths were mainly due to blindness, anorexia, diarrhea, and respiratory arrest. Both adult (mortality = 21)
and young (mortality = 15) animals were affected with the disease. Peste des petits ruminants virus (PPRV) antigen was detected
in the spleen, lung, lymph node, and swab samples by immunocapture enzyme-linked immunosorbent assay. Spleen and lung samples
were also tested and found positive for the presence of F-gene of PPRV by polymerase chain reaction. Thirteen of 20 serum
samples from nearby sheep and goats were found positive for antibodies to PPRV. The disease threatened the huge population
of ibex in the wild life park, which was spread over a large area, but vaccination of the domestic population of sheep and
goats in the surrounding villages appeared to control the disease. 相似文献
57.
Shahzad MA Tauqir NA Ahmad F Nisa MU Sarwar M Tipu MA Tipu MA 《Tropical animal health and production》2011,43(3):685-694
The study investigated the performance response of different dietary protein and energy levels of Nili-Ravi buffalo calves. Sixty buffalo calves of 12–15 months of age and similar body weight (140 ± 14 kg) were divided in to 12 groups,
five animals in each group, according to 4 × 3 factorial arrangements. Twelve rations were formulated containing four levels
of crude protein (CP; 10.5%, 12.20%, 13.80%, and 15.55%) each with three levels (1.72, 2.11, and 2.5 Mcal/Kg) of metabolizable
energy (ME). Experiment lasted for 100 days; first 10 days were given for dietary adaptation. Daily feed consumption in calves
fed all experimental diets were statistically significant (p < 0.05) across all treatments. Higher feed intake was observed in buffalo calves fed diets containing 12.20% and 13.85% CP
with 2.11 Mcal/kg ME. Results of dry matter (DM) digestion were significantly different (p < 0.05) across all treatments. There was a quadratic (p < 0.05) response of DM digestibility for levels of dietary protein while, curvilinear (p < 0.05) trend with respect to dietary energy levels. Daily weight gain of buffalo calves did not show any treatment effect.
The outcome of the present study indicate that 12–15-month-old buffalo calves perform adequately well when fed on diets containing
12.2% CP and 2.10 ME Mcal/Kg. 相似文献
58.
Four ruminally cannulated Nili-Ravi buffalo bulls were used in a 4 × 4 Latin Square Design to determine the influence of varying level of ruminally degradable protein (RDP) on dry matter intake (DMI), ruminal characteristics, digestibility, blood pH, blood urea nitrogen (BUN) and nitrogen (N) balance. Four isonitrogenous and isocaloric diets were formulated. The C diet contained 50% RDP while medium, high and very high RDP diets had 66, 82 and 100% RDP of the total crude protein (CP) and were denoted as MRDP, HRDP and VHRDP, respectively. The bulls were fed ad libitum. Nutrients intake decreased linearly with increasing the RDP proportion of total dietary CP. A quadratic effect of RDP on ruminal pH was noticed with increasing level of RDP with quadratic maxima at 66% RDP diet. Increasing level of dietary RDP also had a quadratic effect on total bacterial and protozoal count with maximum microbial count at 82% RDP diet. Increasing dietary RDP resulted in linear increase in DM digestibility. However, neutral detergent fiber digestibility was decreased linearly with increasing the level of dietary RDP. A linear increase in ruminal NH3–N and BUN was noticed due to increasing level of dietary RDP. Higher positive N balance was noticed in bulls fed C diet compared to those fed MRDP, HRDP and VHRDP diets. The findings of this study indicated that buffalo bulls can effectively utilize 13.12% RDP of DM without any adverse effect on rumen and blood parameters. 相似文献
59.
Ninety-three (93) horses were investigated for serum antibodies to Theileria equi (T. equi) and Babesia caballi (B. caballi) using the immunofluorescent antibody test (IFAT). Seventy-seven (82.8%) horses were seropositive; 31 (33.3%) were positive to T. equi compared to 64 (68.8%) to B. caballi while 18 (19.4%) horses were seropositive to both parasites. No significant differences in antibody frequencies among females and males for either T. equi or B. caballi were noted. Differences in seropositivity to B. caballi among age groups were not significant. Antibodies to T. equi were more frequent than to B.caballi in the age group 5 years and over than in the 1-2 and 2-4 years age groups (p<0.05). Unlike T. equi antibodies, B. caballi antibodies in horses in the county of Caroni were significantly less frequent when compared to other counties (p<0.05). Of 18 (19.4%) clinically ill horses, seven (42.9%) had clinicopathological evidence of anemia. Only one-third (6 of 18) horses were positive for the parasite on Wright-Giemsa stained blood smears and anemia was present in only 2. We report here that B. caballi and not T. equi may be the more common agent of piroplasmosis in Trinidad. 相似文献
60.
Frédéric Delarue Sébastien Gogo Alexandre Buttler Luca Bragazza Vincent E. J. Jassey Grégory Bernard Fatima Laggoun-Défarge 《Journal of Soils and Sediments》2014,14(11):1800-1805