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A series of five experiments were conducted to explore suitable conditions for storing of goldfish embryos in a chilled state. The factors studied were embryo stage, storage temperature, physiological saline solutions and goldfish artificial coelomic fluid (GFACF) medium, antibiotics (penicillin and streptomycin), antioxidants (vitamin E, vitamin C), buffer (Hepes, Tris) and BSA (bovine serum albumin). First, goldfish embryos at eight developmental stages were incubated in aerated and dechlorinated tap water at 0°C for 24 h. Result shows that early developmental stages were most sensitive to chilling. Heartbeat‐stage goldfish embryos were chilled at 0, 4 or 8°C for up to 72 h in water, and chilled storage was possible only for up to 18, 24 and 48 h at 0, 4 and 8°C, respectively, without a decrease in viability. Chilling of goldfish embryos at 8°C in GFACF medium and Dettlaff's solution instead of water and other physiological saline solutions prolonged their viability (p < 0.01). Nevertheless, viability of chilled embryos in GFACF medium was slightly, but non‐significantly, higher than in Dettlaff's solution. Supplementation of the GFACF medium with antibiotics, Hepes or BSA increased the viability of chilled embryos, but the tested vitamin E analogue Trolox, vitamin C or Tris concentration had no effect on embryo viability. The outcome of this series of experiments shows that heartbeat‐stage goldfish embryos could be chilled for 60 h in GFACF supplemented with 25 mm Hepes, 100 U/ml penicillin, 10 μg/l streptomycin and 1 g/l BSA in such a way that embryonic development does not proceed, and viability is not lost.  相似文献   
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The goal of this study was to investigate the use of Jatropha curcas seed meal (JCSM) in different levels as acaricide in diet of rabbits experimentally infested by Hyalomma marginatum marginatum then determining animal performance, anti-tick feeding and its effects on haemogram of rabbits. Thirty healthy mixed-breed rabbits were randomly divided into five equal groups. The first group was kept as a control fed soya bean meal (20%) as a source of protein. Groups from the second to the fifth fed diets contained 2.5%, 5%, 7.5% and 10% of JCSM instead of soya bean meal as a source of protein, respectively. Feeding and watering were given freely throughout the study. Animal performance for treatment groups were recorded from the 1st week up to the 6th week. Then each group divided into two subgroups, and the ticks were introduced to all of one subgroup and the other kept as control, following them until dropped at the end of the 8th week for all groups of the experiment. Feeding and reproductive performance of the adult tick females were determined. Blood samples were collected and analysed for haematological examination at the 0, 6th and 8th weeks post-treatment from all animals. Result revealed that rabbits received diets containing 5%, 7.5% and 10% had significantly (P < 0.05) lower growth performance than control and 2.5% JCSM groups. Feed intake and body weight gain decreased with increasing the level of JCSM in the diet. The result of anti-tick feeding observed that the highest percentage (60–90%) of rejection was recorded in 10% of JCSM group then the other treated groups (20–30%). Egg mass and reproductive index per female were marked increase (P < 0.001) in groups 2.5%, 5% and 7.5% of JCSM. Macrocytic normochromic anaemia was development after 8 weeks of treatment, which changed to microcytic normochromic anaemia after challenge of ticks in groups received 5%, 7.5% and 10% JCSM. Leukopenia, neutopenia and lymphopenia were noticed (P < 0.05) in all treated groups which more drop in the group received 7.5% JCSM. Also, monocytosis was recorded in 7.5% and 10% JCSM groups. In conclusion, JCSM could be use in the treatment of ectoparasites at level less than 10% in diet. Further investigations should be done to detoxification the Jatropha seed meal to decrease the level of its toxicity.  相似文献   
25.
The effects of three levels of a widely used tea nursery fertilizer mixture containing ?, ?,ρ?, Mg and SO4 and hormones on growth and apical dominance were studied using free-growing plants of two vigorous TRI clones.

At the highest level of fertilizer (F2) the plants showed earlier bud-break and an increase in the number and duration of active phases, with a reduction of the dormant phases. These resulted in more growth and dry matter accumulation and in more lateral shoot growth than was obtained with lower levels of fertilizer (FO and Fl). Leaf production on both main and side shoots was increased at the higher levels of nutrition. The results showed that vigorous clones may benefit from higher levels of fertilizer application than the presently recommended rates.

Gibberellic acid (200 ppm) alone or with benzyl adenine (25 ppm) tended to cause earlier bud-break at FO and Fl but not at F2. The percentage bud-break obtained at F2 was, however, similar to that obtained at FO and Fl with the above hormones. GA3 or GA3+BA also increased the height of the plant, the response persisting for at least a month starting a fortnight from the first application. Neither BA (25 ppm) applied alone nor IAA (200 ppm) stimulated bud-break, but IAA increased the height of the plants at the higher levels of fertilizer used. There was an interaction between fertilizer and hormones during the period when the hormones were effective in increasing height.

A relationship was found between the growth of the shoots, natural and induced, and that of the roots. The active plant had about twice the amount of feeder roots as the dormant plant.  相似文献   
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The present study was conducted to evaluate the effect of different concentrations of salts on seed germination and seedling growth of Prosopis juliflora. The experiment was carried out in Forestry Laboratory at Sari Agricultural Sciences and Natural Resources University, Iran. The collected seeds were treated with boiling water and H2SO4 then left to germinate in controlled growth chamber. Seed were grown under salinity levels 100, 200 and 300 mM of CaCl2, NaH2PO4, KNO3 and KH2PO4. Germination parameters and various seedling growth variables such as root and stem length, seedlings fresh and dry weight were measured after 56 days. Results showed that germination percentage significantly decreased as the salinity level of medium increased. Salinity treatments at 100 mM enhanced the percentage of seeds germination and significantly improved the germination index and seeds stamina. In this study, the best treatment was 100 mM salinity for biomass production of seedlings. For Prosopis juliflora, 100 mM salinity significantly enhanced both germination and biomass production.  相似文献   
27.
Pecan trees cv. ‘Moneymaker’ and seedling trees growing in Northern Egypt were sprayed with dinitrocresol mineral oil emulsion, to test its effect on male and female flower bud growth, flowering and fruiting. The treatments had a stimulating effect on growth of male and female flower buds. The treated trees flowered from 1 to 3 weeks earlier than the control. Fruit drop was greatly reduced and, consequently, fruit yield was remarkably increased.  相似文献   
28.
Field experiments were conducted using the biological agentBacillus thuringiensis to control the clearwing moth,Synanthedon myopaeformis (Lep. Aegeriidae) in apple orchards at Alexandria governorate during 1995, 1996 and 1997. Three bacterial varieties ofB. thuringiensis showed significant influence on the reduction of borer infestation. Four applications with the sporic concentration 12×107 spores/ml of each ofB. th. var.kurstaki, B. th. var.alesti andB. th. var.thuringiensis induced 82.5, 51.1 and 42.1% reduction of infestation, respectively. Methods of application showed highly significant effect on infestation level. Sparying after scraping was the best method (80.0%, reduction) followed by painting after scraping (71.5%, reduction) then spraying alone (59.7%, reduction) or painting alone (43.0%, reduction). A control programme was carried out using three applications of the biomaterial, Delfin at the rate of 200 g/100 I.w. during mid-March, early June and mid-August resulted in 88.5–91.4% reduction of infestation.  相似文献   
29.
Growth suppression and delayed puberty may be major concerns for Inhaled Corticosteroids (ICS) treatment in children. Thus, we aimed to assess the effect of long-term ICS on growth and pubertal status in 30 asthmatic children and adolescents in comparison to 20-matched healthy subjects. Auxological measurements, Tanner staging and bone age assessment were performed. Measurements of basal and Lutenizing hormone releasing hormone (LHRH) stimulated follicle stimulating hormone (FSH) and Lutenizing hormone (LH) were done for patients only. In addition, pelvic ultrasound for measurements of uterine length and right ovarian volume was done for females aged > 11 years. Patients' height, bone age and their Standard Deviation Scores (SDSs) were significantly lower, while weight SDSs were significantly higher than controls. ICS at doses > 400 microg/day negatively affected height and its SDS (OR: 8.5, 95% CI: 2.15-33.8), whereas the use of ICS for > 1 year significantly affected all auxological parameters with a particular risk on height SDS (OR: 9, 95% CI = 3.10-10.64) and weight for height SDS (OR: 6.82, 95% CI: 1.36-34.27). Significantly lower stimulated gonadotropins were encountered at doses > 400 microg/day, while a duration > 1 year was associated with significantly lower basal and stimulated gonadotropins. Logistic analysis revealed that the use of ICS for > 1 year carried the highest risk of association with low stimulated FSH (OR: 5.80, 95%, CI: 1.54-33.70) and LH (OR: 8.31, 95% CI: 1.83-50.47). In conclusion, ICS at doses > 400 microg/day carry a significant risk of retarding height of asthmatic children while their continuous use for > 1 year carries significant risks of short stature, weight gain and delayed puberty.  相似文献   
30.
ObjectiveInvestigate the effects of administration of meloxicam and carprofen on the mobility of hens with and without keel fractures.Study designWithin each of two experiments a ‘blinded’ randomised cross over design whereby birds received either the test drug (carprofen or meloxicam) or saline.AnimalsTwo groups of Lohman Brown hens with and without keel bone fractures.MethodsThe first group (n = 63) was treated with carprofen 25 mg kg−1 and saline subcutaneously, twice. The second group (n = 40) was treated with meloxicam (5 mg kg−1) and saline subcutaneously. The latency of birds to fly down from perches 50, 100 and 150 cm above the ground was measured after each treatment. Data from experiment 1 and 2 were analysed separately; the effects of drug treatment compared with saline on landing time for birds with and without keel bone fractures were evaluated using MLwiN.ResultsIn both experiments latency to fly down from perches was longer in hens with keel fractures and there was a significant interaction between perch height and fracture status. For carprofen, at the 50 cm, 100 cm and 150 cm perch heights, birds with fractures took (mean ± SD) 2.5 ± 2.9, 6.8 ± 9.7 and 11.5 ± 13.2 seconds respectively to fly down compared with 1.3 ± 0.5, 2.3 ± 1.2 and 4.2 ± 3.1 seconds for birds without fractures. For meloxicam, at the 50 cm, 100 cm and 150 cm perch heights, birds with fractures took 2.9 ± 2.5, 49.8 ± 85.4 and 100.3 ± 123.6 seconds respectively compared with 0.7 ± 0.5, 2.5 ± 7.1 and 3.0 ± 4.6 seconds to fly down for birds without fractures. There was no significant effect of carprofen or meloxicam treatment.Conclusion and clinical relevanceThese data provide further confirmation that keel fractures reduce the willingness of birds to move from perches.  相似文献   
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