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101.
L W Cook F W Zach J R Fleeker 《Journal of the Association of Official Analytical Chemists》1982,65(2):215-217
A procedure based on steam distillation is described for the determination of residues of the thiocarbamate herbicides diallate and triallate. The herbicides are steam-distilled directly from aqueous suspensions of milk and plant samples and trapped in hexane. After column cleanup on either activated Florisil or silica cartridges, samples are quantitated by gas-liquid chromatography. Recoveries of diallate and triallate from milk, lettuce, peas, corn, canarygrass seed and straw, and flax straw ranged from 77 to 96%. 相似文献
102.
Amy M. Treonis Roger Cook Lorna Dawson Susan J. Grayston Tony Mizen 《Biology and Fertility of Soils》2007,43(5):541-548
We studied the effects of the root endoparasitic nematode Heterodera trifolii on rhizodeposition and the root architecture of white clover (Trifolium repens). Rhizosphere solutions were collected from the root systems of plants growing with and without H. trifolii (200 juveniles per inoculated plant) in sand-based microlysimeters. The organic carbon (C) content of these solutions was
analyzed, and they were applied to plant-free soils to investigate microbial responses. Although plant biomass was unaffected
by nematodes, the architecture of the root systems was significantly altered, with a decrease in overall root length and an
increase in the density of lateral branches from the primary root. The presence of nematodes reduced the concentration of
organic compounds in the rhizosphere solutions but only on the final sampling date (75 days). Analysis of microbial signature
phospholipid fatty acids revealed no change in the structure of the microbial communities in soils to which rhizosphere solutions
were applied. However, these microorganisms did respond with changes in substrate utilization patterns (community-level physiological
profiles). Microbes in soils that received rhizosphere solutions from the nematode-infected clover showed lower utilization
of most substrates but higher utilization of oligosugars. These responses appear to be related to changes in roots and rhizodeposition
associated with nematode infection of clover roots. The results of this study suggest that root herbivory can negatively impact
carbon-limited soil microbial communities via changes in root architecture that moderate rhizodeposition. 相似文献
103.
Nadine Lamberski J Rachel Reader Lizette F Cook Eileen M Johnson David G Baker Linda J Lowenstine 《Journal of zoo and wildlife medicine》2002,33(2):151-156
A juvenile, female North American opossum (Didelphis virginiana) died of verminous pneumonia caused by Didelphostrongylus haysei despite aggressive treatment with oral fenbendazole, corticosteroids, and antibiotics. This prompted a retrospective study of lungworm infection in opossums, during which 19 additional necropsy reports from opossums were reviewed. Including the subject of this report, a total of 11 (55%) of these cases included a diagnosis of lungworm infection. This diagnosis was considered to have contributed to death in eight out of the 11 cases (73%). Histologically, 10 of the 11 (91%) opossums had granulomatous bronchopneumonia with small to moderate numbers of adult nematodes in the airways and parenchyma. Four of the 11 (36%) opossums had free larvae within the parenchyma or terminal airways. Inflammation was usually associated with larvae, degenerating parasites, and nonintact adult nematodes. Superimposed bacterial pneumonia was evident in three animals, and sections of lung examined from all the opossums were characterized by moderate to severe smooth-muscle hyperplasia in airways, including terminal respiratory bronchioles and alveolar ducts. Nine animals had prominent medial smooth-muscle hyperplasia in small- and medium-sized arterioles. Lesions in other organs, particularly in liver, heart, and gastrointestinal tract, were frequently identified. Three animals had concomitant septicemia or bacterial bronchopneumonia (or both), which contributed to the cause of death. Seven animals had gastric nematodosis (Physaloptera sp.), although three of them had been treated with a 14-day course of fenbendazole. 相似文献
104.
TG McEvoy 《Reproduction in domestic animals》2003,38(4):268-275
Assisted reproductive technologies, as applied to domestic animals, can exert both novel and wide‐ranging influences on the development, viability and welfare of offspring. Some of the changes are evident immediately or soon after the time at which a manipulative procedure is carried out, while other changes may not be evident until later in development or, perhaps, may remain undetected throughout an animal's lifetime. The present review explores some of the consequences – in terms of foetal, placental, neonatal and post‐natal effects – of exposing embryos of cattle, sheep and other species to in vitro culture per se or, during culture, to physically invasive technologies including gene injection and nuclear transfer. The innate sensitivity of oocytes and recently fertilized eggs to their in vitro environment is illustrated by an examination of the later developmental repercussions resulting from apparently innocuous choices related to in vitro culture medium formulations. In contrast, an inherent resilience and paradoxical readiness to resume development following the traumas of nuclear transfer procedures is also in evidence. The extent to which assisted reproductive technologies will succeed, where relevant, in the domestic animal sector will be influenced by our appreciation of embryo requirements, for both short‐ and long‐term developmental fitness, during their earliest developmental stages. Evidence of species‐specific needs is testimony to the challenges ahead. Ultimately, our ability and inclination to resolve the limitations associated with current procedures will probably be greatly enhanced if predictive indicators (genetic, epigenetic or functional markers) of later developmental fitness can be identified. 相似文献
105.
Evaluation of pudendal reflexes and effects of pudendal branch conditioning on those reflexes was carried out in 2 studies. In the first study of pudendal reflexes, 20 adult male and female mixed-breed cats underwent surgical isolation of the anal branch, urethral branch, and distal trunk (consisting primarily of the dorsal nerve of the penis/clitoris) of the pudendal nerve. Reflexes were tested in all possible ipsilateral and contralateral test-response combinations. Latency values and effects of increasing stimulus rate on response amplitude were recorded. Reflexes were detected in all combinations, with response latencies between 6.3 and 13.0 ms. Response amplitudes were diminished at stimulus rates of 3 to 5 Hz, and responses were apparently abolished at 4 to 16 Hz, suggesting that pudendal reflexes are polysynaptic. In the second study of conditioning effects, 9 adult male and female mixed-breed cats underwent preparation similar to that for study 1. A train of conditioning stimuli was applied to branches of the pudendal nerve prior to attempting to induce reflex responses, as performed in study 1. Conditioning completely abolished reflex responses for a period of 70 to 130 ms. Reflex responses were diminished in amplitude, compared with those observed during preconditioning trials, for 180 to 300 ms after conditioning. 相似文献
106.
Annual surveys of winter wheat diseases in England and Wales provide information on the relative severity of the leaf and stem-base disease complex. Septoria tritici was the most damaging disease during the 5-year period 1985–1989 causing annual losses estimated to be 0.329 Mt compared with 0.251 Mt and 0.231 Mt for eyespot and mildew, the next most damaging winter wheat diseases. Annual losses during the period averaged 1.078 Mt excluding losses attributable to the fusarium diseases, for which no satisfactory yield loss relationships are available. Sowing date and length of break from cereals exert a strong influence on incidence of eyespot and losses attributable to the disease and, on the basis of these surveys, growing all winter wheat crops after a 1-year break would prevent national losses of 100 kt annually. 相似文献
107.
Cardiomyopathy and woolly haircoat syndrome of Poll Hereford cattle: electrocardiographic findings in affected and unaffected calves 总被引:1,自引:0,他引:1
Electrocardiograms were recorded from 4 calves with cardiomyopathy and woolly haircoat syndrome (CWH), a lethal autosomal recessive trait of Poll Hereford cattle and from 9 unaffected calves. Electrocardiograms of calves with CWH were characterised by multifocal ventricular premature contractions which occurred singly, in pairs, in runs and as episodes of ventricular tachycardia. Bigeminal rhythms were recorded occasionally. The frequency of ventricular premature contractions ranged from 5 to 120.min-1. Ventricular premature contractions in calves with CWH were attributed to myocardial degeneration and fibrosis which were observed grossly and microscopically. Electrocardiograms in unaffected calves were characterised by normal sinus rhythm and by variation in the morphology of wave forms between animals. The durations of the various wave forms were less than those previously recorded from adult cattle. 相似文献
108.
Escherichia coli numbers and histopathological changes were studied in the respiratory tract of line 151 chickens intranasally inoculated with infectious bronchitis virus (IBV) and/or virulent E. coli; this line is highly susceptible to IBV. Chickens inoculated with IBV alone showed increased numbers of E. coli in the trachea and had tracheitis, airsacculitis, and bronchiolitis. One of 17 chickens inoculated with IBV alone died with fibrinopurulent serositis. Chickens inoculated with IBV and E. coli had more severe and persistent respiratory lesions than those inoculated with IBV alone. E. coli was isolated from tracheas of chickens inoculated with IBV and E. coli more frequently than from chickens inoculated with IBV alone. In this group, 14 of 27 chickens died with tracheal plugs or with fibrinopurulent serositis. There was neither increased numbers of E. coli nor significant lesions in the respiratory tract of the group inoculated with E. coli alone. These results suggest that IBV may facilitate E. coli invasion into the lower respiratory tract of the chicken. 相似文献
109.
S L Ihle R W Nelson J R Cook 《Journal of the American Veterinary Medical Association》1988,192(1):71-72
Hypercalcemia caused by primary hyperparathyroidism was believed to be responsible for seizures in a dog. A diagnostic evaluation showed no primary causes of seizures. After surgical excision of the adenomatous parathyroid gland, phenobarbital treatment was discontinued, without recurrence of seizures. 相似文献
110.
Immune and bone properties of chicks consuming corn contaminated with a Fusarium that induces dyschondroplasia 总被引:1,自引:0,他引:1
A study was conducted to contrast the dyschondroplasia-inducing capability of several species of Fusarium with that of the natural fungi found in poultry diets and litter. Day-old broiler chicks were fed pure corn cultures of specific fungal isolates for 3 weeks. Humoral immunity to sheep red blood cells (SRBC), body weight, valgus and varus leg deformities, incidence of dyschondroplasia, and mechanical properties of the tibiotarsi were examined. F. equiseti #15 was the only fungal isolate to induce dyschondroplasia to any significant degree, which confirmed previous work in Minnesota. This isolate also suppressed growth rate and humoral immunity, although dyschondroplasia sometimes did occur without associated immunosuppression and growth depression. Bone strength of the tibiotarsal diaphysis was normal, and gross lesions of valgus and varus leg deformities did not appear to be related to the incidence of dyschondroplasia in the 3-week-old chicks. 相似文献