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31.
The effect of two different sources of magnesium fertilization, Epsom salt (MgSO4·7H2O) or dolomite (MgCO3·CaCO3), on enzymatic discoloration, phenolic, crude lipid, phospholipid and Mg content, of Katahdin potatoes was studied over a 3 yr. period. Tubers grown in soils receiving either Epsom salt, or dolomite, were compared with control tubers receiving no added magnesium. Tubers from plants receiving Epsom salt discolored the least, were lowest in phenols and highest in crude lipid, phospholipid and Mg contents. However, when dolomite was the source of Mg the tubers discolored more, were higher in phenols, and were lower in Mg content than control tubers. The source of Mg fertilizer was very important in determining the quality of tubers.  相似文献   
32.
A 7-year-old, 46-kg spayed female rottweiler dog was presented with sudden onset of disorientation, bilateral convergent strabismus, and enophthalmos. Diagnostic workup revealed hypothyroid-associated cranial neuropathy. Symptoms abated considerably upon treatment with levothyroxine-sodium (T4) at an initial dose of 800 μg/kg body weight (BW), PO, q12h, which was reduced 3 days later to 600 μg/kg BW, q12h due to severe agitation and panting. Two weeks later the dosage of the levothyroxine-sodium (T4) was reduced to 400 μg/kg BW in the morning and 600 μg/kg BW in the evening. Eight weeks after the initial presentation, the dog had recovered with only mild convergent strabismus in the right eye. This is the first case report of suspected hypothyroid-associated neuropathy resulting in these symptoms.  相似文献   
33.
In a 2-year grow-out trial, triploid Sydney rock oysters, Saccostrea commercialis (Iredale & Roughley), from two initial size grades grew faster (in terms of both mean whole weight and shell height) than the equivalent initial size grades of sibling diploids (P < 0.05). Small size grade triploids caught up with and had significantly heavier (P < 0.05) final whole weights than large size grade diploids after a 2-years grow-out period. The initial size grade had a significant effect on final mean whole weight and shell height for both ploidy types. After the 2-years grow-out trial, the final mean whole weights (but not shell heights) of small and large diploids (35.8 ± 0.6 g and 39.4 ± 0.5 g, respectively) were significantly different (P < 0.05). Small and large triploids grew at a similar rate for the first 18 months despite the significantly (P < 0.05) heavier final mean weight of large grade triploids (48.4 ± 0.8 g and 61.2 ± 0.7 g, respectively). The effect of the initial size grade on subsequent growth of both diploid and triploid oysters which was demonstrated in the present study is of significant commercial value to hatchery and nursery operators as well as growers of single seed oysters. In addition, small-grade triploids appeared to be more valuable in terms of potential growth rate than all diploid grades. There was no significant difference in the final percentage triploidy between small and large grade triploids. A large proportion of diploid/triploid mosaicism was detected in adult oysters.  相似文献   
34.
Outbreaks of respiratory disease constitute a major health problem in herds of finishing pigs and their aetiology often remains unclear. In this study, 16 outbreaks of respiratory disease with acute clinical signs in finishing pigs were investigated to determine which infectious agents were involved. From each herd four diseased and two clinically healthy pigs were examined pathologically and for the presence of viruses, bacteria and mycoplasmas. In addition, paired blood samples from 10 groupmates of the diseased pigs were tested for antibodies against commonly known causal agents of respiratory disease. A clear diagnosis was possible in 12 of the 16 outbreaks. Seven were due to an infection with influenza virus and five were due to an infection with Actinobacillus pleuropneumoniae. A combination of influenza virus and A pleuropneumoniae may have caused one other outbreak, but no clear cause could be established for the other three outbreaks.  相似文献   
35.
1. The requirements of all classes of chickens for molybdenum are 0.03 mg/kg diet or less.

2. Dietary sulphate and tungstate both reduce the availability of dietary molybdate.

3. No evidence was obtained that either the clubbed down, ginger hair syndrome in chicks or the scabby hip syndrome in broilers is due to a simple molybdenum deficiency.  相似文献   

36.
1. Large doses of tungsten, administered to the chick either by injection or by feeding, increased tissue concentrations of tungsten and decreased tissue concentrations of molybdenum and tissue activities of xanthine dehydrogenase.

2. The rate of loss of large doses of tungsten from the liver occurred in an exponential manner with a half‐life of 27 h.

3. When tungsten was administered to chicks fed on a semi‐synthetic diet containing abnormally low concentrations of molybdenum, the activity of hepatic xanthine dehydrogenase was reduced to negligible levels.

4. The alterations in molybdenum metabolism resulting from the administration of large doses of tungsten to the chick appears to be the result of tungsten toxicity and not of molybdenum deficiency.

5. Deaths from tungsten toxicity occurred when tissue concentrations of tungsten were increased to approximately 25 μzg/g liver. At this tissue tungstencon centration the activity of xanthine dehydrogenase was zero.  相似文献   

37.
A 7-year-old female spayed European shorthair cat was presented because of visual reduction and a green reflex in the right eye. Examination revealed a 'D-shaped' pupil in the right eye and a 'reverse-D-shaped' pupil in the left eye. Both eyes showed fibrinous anterior uveitis with exudates in the anterior chamber and precipitates on the posterior surface of the cornea. In both eyes a chorioretinitis was diagnosed which caused partial retinal detachment and peripapillary oedema in the left eye. Histopathology revealed intestinal and ocular lymphosarcoma. The aberrant pupil shapes which persisted after death were due to infiltration of the iris stroma and were not caused neurologically. The observation that in both eyes only the medial parts of the iris were affected could not be explained.  相似文献   
38.
39.
PURPOSE: The purpose of this study was to determine if intravenous hypertonic hydroxyethyl starch (7.5%/6%) (HES) could decrease the intraocular pressure (IOP) in healthy normotensive dogs, and compare its effect with that of mannitol (20%) (experimental study). In addition, the potential IOP-lowering effect of hypertonic HES was evaluated in six dogs with primary glaucoma (clinical study). MATERIAL AND METHODS: Experimental study: eight male ophthalmoscopically and clinically healthy Beagles were included in this study. The IOP of each dog was measured by applanation tonometry in both eyes to obtain control values at 10:00, 10:15, 10:30, 10:45, 11:00 a.m., and then every hour until 6:00 p.m. prior to the first treatment (control period). Each dog received, with at least 2-week intervals and in a random order, an intravenous (IV) infusion of 4 mL/kg hypertonic HES (1.2 g/kg NaCl; 0.96 g/kg HES) and 4 mL/kg mannitol 20% (1 g/kg) over a period of 15 min starting at 10:00 a.m. IOP was measured oculus uterque (OU) at the same time intervals as in the control study. The differences in IOP between the treatment groups and the baseline IOP (before the start of infusion), between oculus sinister (OS) and oculus dexter (OD) and between the same time points of all groups were determined with a Student's t-test for paired samples (P = 0.05). Clinical study: six dogs with primary glaucoma (representing seven eyes) received an IV infusion of 4 mL/kg hypertonic HES over a period of 15 min. IOP was measured before and 15 and 30 min after starting the infusion. RESULTS: Experimental study: no significant difference between IOP of both eyes was found. A significant decrease in IOP from baseline value was recorded at 15, 30, 45, and 60 min after the start of mannitol infusion (mean amplitude in IOP decrease 3.21 mmHg; P < 0.05) and at 15 and 30 min in dogs treated with HES (mean amplitude in IOP decrease 2.43 mmHg; P < 0.05). At 120 and 180 min there was a significantly higher IOP (P < 0.05) in HES treatment group compared to the values of the control group. Clinical study: in 5/7 eyes diagnosed with primary glaucoma a maximum decrease in IOP of an average of 24% from the baseline value (IOP before start of the infusion) was observed (range of decrease 2-21 mmHg). In three of these five cases the maximum decrease was reached at 15 min and in two cases at 30 min. In one case an increase in IOP of 35% (+ 18 mmHg) was seen after 15 min and 26% (+ 13 mmHg) after 30 min. Case 4 showed an increase in IOP of 5% (+ 3 mmHg) after 15 min and a decrease of 6% (- 4 mmHg) after 30 min. CONCLUSIONS: Intravenous hypertonic HES is comparable to intravenous mannitol 20% in lowering the intraocular pressure in healthy normotensive dogs. But this effect lasted half an hour longer after mannitol. In 6/7 eyes with primary glaucoma, hypertonic HES decreased IOP.  相似文献   
40.
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