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71.
On the basis of clinical signs and histological findings eight 9-month-old male rusa deer ( Cervus timorensis ) were diagnosed with sheep associated-malignant catarrhal fever. Following a variable course involving rectal temperatures around 40.5°C, depression, inappetence, diarrhoea, corneal opacity and hypopyon all animals died or were euthanased over a 5-week period. Severe multifocal vasculitis, mainly periglomerular and in the arcuate vessels were consistent histological findings which in the past have been adequate to confirm clinical diagnosis of sheep associated-malignant catarrhal fever. A nested poly-merase chain reaction test has been used to detect a sheep associated-malignant catarrhal fever PRC product, 238 base-pairs in size, in DNA extracted from lymphocyte preparations. The result supported the diagnosis of sheep associated-malignant catarrhal fever in these deer.  相似文献   
72.
SUMMARY A three-year-old neutered female Border Collie was presented with in-appetence, vomiting and diarrhoea. Abdominal radiographs revealed an obstructive pattern but no physical obstruction was evident at laparotomy. A diagnosis of chronic intestinal pseudo-obstruction was made based on histopathological changes in intestinal biopsies. Treatment was unsuccessful and the dog deteriorated progressively until euthanased five weeks after presentation.  相似文献   
73.
Phenylbutazone given during the perisurgical period has been reported to increase the intensity and duration of thiamylal anaesthesia in horses. A possible mechanism of competitive plasma protein binding has been suggested. The purpose of the present study was to experimentally reproduce the phenomenon of increased intensity and/or duration of thiamylal anaesthesia and to determine if there is competitive displacement of plasma protein bound thiamylal by phenylbutazone. Six ponies each received one of three treatments, 11 mg/kg intravenous (i.v.) thiamylal; 8.8 mg/kg i.v. phenylbutazone; and 11 mg/kg i.v. thiamylal with 8.8 mg/kg i.v. phenylbutazone given 9 min later. Thirteen blood samples were collected from 0 time through 600 min following drug administration and plasma drug concentrations quantified by high performance liquid chromatography. The pharmacokinetics of thiamylal and phenylbutazone were best described by three- and two-compartment models, respectively. There were no significant differences in pharmacokinetic parameters for thiamylal in the presence of phenylbutazone. However, there were differences in phenylbutazone pharmacokinetics when preceded by thiamylal administration. Unbound phenylbutazone concentrations were increased at 171, 231 and 351 min when given with thiamylal, accompanied by decreases in per cent bound phenylbutazone (P < 0.05). There were also significant (P < 0.05) changes in per cent plasma protein binding of thiamylal and phenylbutazone between 120 and 360 min, when in combination. No changes in intensity or duration of anaesthesia were observed.  相似文献   
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75.
The theory of fractal geometry is presented with reference to soil structure. Recent work on relating fractal structure to pore structure in soils is reviewed. It is suggested that the connection made in previous work between the fractal dimension and soil moisture retention curves is based on simplified assumptions that complicate the interpretation of results. A simple method for estimating the fractal dimension, D, of natural aggregates which circumvents some of these assumptions is presented. Preliminary results of aggregates from soils under different management systems show that, for the soils examined, D ranged from 2.75 to 2.93. The use of D to quantify heterogeneity in soil is explored.  相似文献   
76.
Normal anatomic variation in the amount of fat within the petrous temporal bone of dogs can result in a magnetic resonance (MR) imaging pseudolesion. Focal hyperintense areas in the region of the hippocampus on T1-weighted, T2-weighted, and fluid-attenuated inversion recovery imaging sequences were noted in a dog being imaged for seizure activity. Further investigation of this region, aided by the use of cadaveric specimens, led to the identification of normal anatomic variability in the amount of fat in the substantia spongiosa of the petrous temporal bone. The presence of normal adipose tissue was confirmed histopathologically. Fat suppression MR imaging sequences can be used to differentiate whether hyperintensity ventral to the hippocampus is a result of a pathologic process, or fat in the substantia spongiosa of the petrous temporal bone.  相似文献   
77.
Data from recent oceanographic cruises show that phytoplankton community structure in the Ross Sea is related to mixed layer depth. Diatoms dominate in highly stratified waters, whereas Phaeocystis antarctica assemblages dominate where waters are more deeply mixed. The drawdown of both carbon dioxide (CO2) and nitrate per mole of phosphate and the rate of new production by diatoms are much lower than that measured for P. antarctica. Consequently, the capacity of the biological community to draw down atmospheric CO2 and transport it to the deep ocean could diminish dramatically if predicted increases in upper ocean stratification due to climate warming should occur.  相似文献   
78.
PAWSEY  R. G.; YOUNG  C. W. T. 《Forestry》1969,42(2):145-164
Evidence from the assessment of two large European larch (Larixdecidua Mill.) provenance experiments replicated on a numberof sites in England, Wales, and Scotland, and from other observations,suggested that: (a) Larch canker was not caused by frost, butwas probably due to primary infection by the fungus Trichoscyphellawillkommii (Hart.) Nannf. (b) Scottish provenances of Europeanlarch were more susceptible to canker and dieback than wereCarpathian provenances, (c) Canker and epidemic dieback of Europeanlarch were unrelated phenomena, although the relative susceptibilityof the provenances examined was similar for both conditions.  相似文献   
79.
80.
SUMMARY Lice were found in samples of baled wool from 198 of 464 flocks treated to eliminate an Infestation in the period July 1988 to June 1990. In 287 flocks the Insecticide was applied as a backline treatment and in 177 flocks a shower dip was used. Of these flocks, 41.5% and 44.6%, respectively, were found to be infested at the following shearing. After adjusting for the accuracy of the test, It was estimated that infestation in 2 consecutive 12-month periods occurred in 52.6% of flocks with a real incidence rate of 27.4%. Using these estimates, it was calculated that in 34.7% of infested flocks treatment did not kill all lice. There were no differences in the proportion of consecutive infestations between flocks treated with any of the 3 chemicals applied as backline treatments. Among flocks treated In a shower dip, 68.4% using coumaphos, 37.8% using diazlnon and 41.5% using cyhalothrin had consecutive Infestations (P < 0.05). The detection of lice in 63.2% of flocks that were treated with magnesium fluosilicate was, in part, attributed to the application of this chemical by one operator.  相似文献   
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