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排序方式: 共有107条查询结果,搜索用时 31 毫秒
61.
Environmental arsenic (As) contamination, considered as the largest mass poisoning of the human population, has become a serious health concern for the people of South East Asia, including those living in the Bengal delta. An As-resistant strain, KUMAs15, was isolated from the As-contaminated fields in Nadia Ddistrict in West Bengal, India and was evaluated for its possible use in environmental As bioremediation. Molecular identification based on 16S rDNA gene sequencing revealed that the strain belonged to the genus Micrococcus. The strain tolerated high levels of As and oxidized arsenite under the culture condition. The strain also accumulated large quantities of As when exposed to a wide range of environmentally relevant concentrations of inorganic As. Analysis of the aoxB, arsB, and arsC gene expression explained the underlying cause of arsenite oxidation and As accumulation by KUMAs15. The As-resistant strain KUMAs15 of Micrococcus sp. was suggested to be a potential environmental As decontaminant. 相似文献
62.
Quantification of nasal airflow resistance in English bulldogs using computed tomography and computational fluid dynamics
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Eric T. Hostnik Brian A. Scansen Rachel Zielinski Samir N. Ghadiali 《Veterinary radiology & ultrasound》2017,58(5):542-551
Stenotic nares, edematous intranasal turbinates, mucosal swelling, and an elongated, thickened soft palate are common sources of airflow resistance for dogs with brachycephalic airway syndrome. Surgery has focused on enlarging the nasal apertures and reducing tissue of the soft palate. However, objective measures of surgical efficacy are lacking. Twenty‐one English bulldogs without previous surgery were recruited for this prospective, pilot study. Computed tomography was performed using conscious sedation and without endotracheal intubation using a 128 multidetector computed tomography scanner. Raw multidetector computed tomography data were rendered to create a three‐dimensional surface mesh model by automatic segmentation of the air‐filled nasal passage from the nares to the caudal soft palate. Three‐dimensional surface models were used to construct computational fluid dynamics models of nasal airflow resistance from the nares to the caudal aspect of the soft palate. The computational fluid dynamics models were used to simulate airflow in each dog and airway resistance varied widely with a median 36.46 (Pa/mm)/(l/s) and an interquartile range of 19.84 to 90.74 (Pa/mm)/(/s). In 19/21 dogs, the rostral third of the nasal passage exhibited a larger airflow resistance than the caudal and middle regions of the nasal passage. In addition, computational fluid dynamics data indicated that overall measures of airflow resistance may significantly underestimate the maximum local resistance. We conclude that computational fluid dynamics models derived from nasal multidetector computed tomography can quantify airway resistance in brachycephalic dogs. This methodology represents a novel approach to noninvasively quantify airflow resistance and may have utility for objectively studying effects of surgical interventions in canine brachycephalic airway syndrome. 相似文献
63.
Afandi Imane Talba Sophia Benhra Ali Benbrahim Samir Chfiri Rachid Labonne Maylis Masski Hicham Laë Raymond Tito De Morais Luis Bekkali Mohammed Bouthir Fatima Zohra 《International Aquatic Research》2018,10(2):191-205
International Aquatic Research - In the current study, ten elements contents (Fe, Zn, Mn, Cu, Cr, Co, Ni, Cd, Pb and Hg) have been measured in muscle and liver of four pelagic fish species... 相似文献
64.
Solid-substrate fermentation of corn fiber by Phanerochaete chrysosporium and subsequent fermentation of hydrolysate into ethanol 总被引:2,自引:0,他引:2
Shrestha P Rasmussen M Khanal SK Pometto AL van Leeuwen JH 《Journal of agricultural and food chemistry》2008,56(11):3918-3924
The goal of this study was to develop a fungal process for ethanol production from corn fiber. Laboratory-scale solid-substrate fermentation was performed using the white-rot fungus Phanerochaete chrysosporium in 1 L polypropylene bottles as reactors via incubation at 37 degrees C for up to 3 days. Extracellular enzymes produced in situ by P. chrysosporium degraded lignin and enhanced saccharification of polysaccharides in corn fiber. The percentage biomass weight loss and Klason lignin reduction were 34 and 41%, respectively. Anaerobic incubation at 37 degrees C following 2 day incubation reduced the fungal sugar consumption and enhanced the in situ cellulolytic enzyme activities. Two days of aerobic solid-substrate fermentation of corn fiber with P. chrysosporium, followed by anaerobic static submerged-culture fermentation resulted in 1.7 g of ethanol/100 g of corn fiber in 6 days, whereas yeast ( Saccharomyces cerevisiae) cocultured with P. chrysosporium demonstrated enhanced ethanol production of 3 g of ethanol/100 g of corn fiber. Specific enzyme activity assays suggested starch and hemi/cellulose contribution of fermentable sugar. 相似文献
65.
Plasma concentrations of tumor necrosis factor-alpha in cats with congestive heart failure 总被引:4,自引:0,他引:4
Meurs KM Fox PR Miller MW Kapadia S Mann DL 《American journal of veterinary research》2002,63(5):640-642
OBJECTIVE: To determine whether plasma concentrations of tumor necrosis factor-alpha (TNF-alpha) are increased in cats with congestive heart failure (CHF) secondary to cardiomyopathy. ANIMALS: 26 adult cats with CHF and cardiomyopathy and 9 healthy control cats. PROCEDURE: Plasma concentrations of TNF-alpha were measured in cats with CHF and cardiomyopathy. Tumor necrosis factor-alpha was measured by quantifying cytotoxic effects of TNF-alpha on L929 murine fibrosarcoma cells. RESULTS: Concentrations of TNF-alpha were increased (0.13 to 3.6 U/ml) in 10 of 26 cats with CHF but were undetectable in the other 16 cats with CHF and all control cats. In 20 of 26 cats with CHF right-sided heart failure (RHF) was evident; TNF-alpha concentrations were increased in 9 of these 20 cats. The remaining 6 cats had left-sided heart failure (LHF); TNF-alpha concentrations were increased in only 1 of these cats. Age of cats with LHF (mean +/- SD, 12.1+/-6.2 years) was not significantly different from age of the cohort with RHF (10.5+/-5.2 years). Body weight of cats with increased TNFalpha concentrations (5.4+/-1.8 kg) was not significantly different from body weight of cats with CHF that did not have measurable concentrations of TNF-alpha (4.7+/-1.6 kg). CONCLUSIONS AND CLINICAL RELEVANCE: Concentrations of TNF-alpha were increased in many cats with CHF. Cats with RHF were most likely to have increased TNF-alpha concentrations. Increased plasma concentrations of TNF-alpha in cats with CHF may offer insights into the pathophysiologic mechanisms of heart failure and provide targets for therapeutic interventions. 相似文献
66.
Samir El-Shafey M. Fathalla I. Habib S. Al-Dahash 《The Canadian veterinary journal. La revue veterinaire canadienne》1980,21(5):165-167
Ovaries of two goats with persistent corpus luteum were studied by histochemical methods. Lutein cells showed moderate alkaline phosphatase and acid phosphatase activity associated with strong delta 5-3β-hydroxysteroid dehydrogenase and succinic tetrazolium reductase activity. The results are interpreted as an indication that the corpus luteum was functioning. 相似文献
67.
Effects of Rosmarinus officinalis L. essential oils supplementation on digestion,colostrum production of dairy ewes and lamb mortality and growth
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Samir Smeti Margalida Joy Hadhami Hajji José Luis Alabart Fernando Muñoz Mokhtar Mahouachi Naziha Atti 《Animal Science Journal》2015,86(7):679-688
The aim of this study was to evaluate the effect of rosemary essential oils (REO) and the forage nature on ewes' performances, immune response and lambs' growth and mortality. Forty‐eight dairy ewes (Sicilo‐Sarde) were fed oat‐hay or oat‐silage supplemented with 400 g of concentrate during pregnancy and 600 g during postpartum. The experimental concentrate contained the same mixture as the control (barley, soybean meal and mineral vitamin supplement) more 0.6 g/kg of REO. Two groups were obtained with each forage (Hay groups: H‐C and H‐REO; Silage groups: S‐C and S‐REO). REO increased the dry matter (DM) intake, the nitrogen intake and retention being higher with the silage groups (P < 0.05). REO increased solid non‐fat (P = 0.004) and fat contents of colostrum which was higher with hay (P = 0.002). REO decreased lamb mortality (P < 0.05) which averaged 21% for control groups and 6% for H‐REO, while no mortality was recorded with S‐REO. REO dietary supply improved forage intake and tended to ameliorate colostrum production; it could be a natural additive to improve ewes' performances. 相似文献
68.
1. Despite the importance of Llangorse Lake as the largest natural body of fresh water in South Wales, no long‐term limnological project has ever been planned for the lake. 2. A mass of data is available from sampling carried out at intervals since 1961, but these visits were for various reasons and used widely differing levels of expertise. However, from these data some indications of seasonal variations, effects of climate and human interference on the lake system over 30 years have been inferred. 3. Depth soundings revealed the general shallowness of the lake with two deeper basins. Wind action oxygenated the water and stirred up sediments releasing nutrients and resting algal stages into the water column. Periods of thermal stratification were transient in summer. Secchi disc and light readings showed greatest light penetration in April/May. The lake water remained alkaline throughout. Dissolved ammonia values were low in the 1960s, increased in the 1970s and decreased again in the 1980s. Nitrite‐ and nitrate‐nitrogen showed a converse pattern over the years. Phosphate (PO4 P) and silica (SiO2) values were highest in the 1960s, showed a decrease in the 1970s and early‐1980s, and rose again towards the end of the decade, as did the chloride values. Seasonal fluctuations of all nutrients were observed. 4. Diatoms dominated the phytoplankton, with highest production in summer and early autumn. The Cyanobacteria (blue–green algae) produced blooms in the 1960s and 1970s, but Chlorophyta (green algae) increased over the years and dominated in the 1980s after a diversion of sewage from the lake. Diatom production followed a vernal and late summer periodicity common in temperate lakes. Results from diatom stratigraphy of the deep sediment cores indicated a change from epiphytic to planktonic species related to land‐use change and a subsequent increase in soil erosion and turbidity. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
69.
Valadez-Moctezuma Ernestina Samah Samir Zelaya-Molina Lily Xochilt Díaz-Rivera Joaquín Bernardo 《植物病害和植物保护杂志》2020,127(6):753-762
Journal of Plant Diseases and Protection - In Mexico, okra (Abelmoschus esculentus L.) is grown mainly for export, but its production is affected by various pests and diseases. Plants with mosaic... 相似文献
70.