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61.
Quantitative phytochemical variation was determined from roots and inflorescences of native plant populations in the genus Echinacea. Specimens were collected in situ throughout the natural range of each putative taxon and transplanted to greenhouse cultivation. Ethanolic extracts from individual plants were separated by reversed-phase HPLC to quantify the alkamides, polyenes/ynes, and phenolics, and then grouped by age and taxonomically, according to a recent morphometric taxonomic revision of the genus. Canonical discriminant analysis revealed that cichoric acid, the diene alkamides 1-3 and 7, and ketoalkene 24 were the best taxonomic markers. Mean content for each of 26 phytochemicals revealed useful agronomic information, such as those varieties and organs with the highest accumulations, as well as the optimal age and growth conditions for each variety. The highest amounts of cichoric acid were measured from the older, wild inflorescences of E. pallida var.sanguinea, whereas the highest quantities of the alkamides 1-3 and 7 were present in roots of wild and transplanted E. purpurea. Baseline phytochemical data and chromatographic profiles for all types of wild Echinacea may be used for protection of wild stands, germplasm identification, and crop improvement.  相似文献   
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63.
In this paper we report the development and testing of a fowlpox virus vector system. Insertion sites in non-essential regions within the terminal inverted repeats of the virus have been characterised. Foreign genes inserted into these sites are shown to be present in two copies in the resultant recombinant virus. To test the potential use of this vector as a live vaccine the fusion gene of Newcastle disease virus (NDV) has been inserted into a vaccine strain of fowlpox virus, and inoculated into chickens. The experiments demonstrate the ability of the recombinant to protect chickens against challenge by a virulent strain of NDV and to elicit the formation of anti-fusion protein antibody.  相似文献   
64.
The aim of this study was to test the functional status of uterine oxytocin receptors in cows in vivo around parturition. The animals received consecutive, intra‐arterial injections of 800, 1600 and 3200 mU of oxytocin at three different stages: during late gestation (days 260–274), at 12 h and at 24 h after intramuscular injection of a prostaglandin F analogue at day 275 to induce parturition. Cows (n=6) had been provided with myometrial electrodes and a catheter had been installed in the aorta and in a branch of the uterine vein (UV). Regular blood samples were obtained from the UV from 5 min before until 45 min after each oxytocin injection to measure plasma levels of prostaglandin F (PGF) and oxytocin. Uterine electromyographic (EMG) activity was registered continuously during each experiment. The increase of oxytocin levels in UV plasma after intra‐arterial injections was dose dependent (p < 0.02). Pre‐ and post treatment oxytocin levels at 24 h after induction of parturition were significantly increased (p=0.0313). Both during late pregnancy and at 12 h after induction of parturition, oxytocin caused a significant increase in EMG activity (p=0.022). After the 3200 mU dose the increase was significantly higher than with the other 2 doses (p=0.004). After each dose, EMG activity returned to baseline levels within some 15 min. At 24 h after induction of parturition, the pre‐treatment level of EMG activity had increased. Doses of 800 mU and 1600 mU of oxytocin produced a significant (p=0.022) increment of EMG activity, which was of the same magnitude as during the preceding stages; after 3200 mU of oxytocin the response was significantly higher than before (p=0.008). No significant increases of PGF levels in UV plasma could be measured after oxytocin injections at any of the three stages. It is concluded that the myometrium of the pregnant cow responds in vivo to physiological doses of oxytocin. At 24 h after induction of parturition, when luteolysis has occurred and a parturient pattern of parturient myometrial activity has already started to develop, the response is enhanced. Physiological doses of oxytocin did not evoke a spurt release of PGF in uterine venous blood during the peripartal period.  相似文献   
65.
Sheep antibodies against a pig E-rosette-forming lymphoblastic T lymphoma raised by two intravenous injections of 10(10) cells showed little lymphocytotoxic activity which could be absorbed with red cells, alveolar macrophages or kidney or liver cell homogenates. Bone marrow absorption yielded subpopulation specific antibody which binds to E rosette-forming cells (E.RFC) using either complement-mediated cytotoxicity or indirect antiglobulin rosette formation. In 30 blood lymphocyte preparations from 20 pigs with a range of approximately 20-85% E rosettes the mean E% 43.5 +/- 2.7 agreed with the % antigen+ cells by cytotoxicity mean = 42.6 +/- 2.7 and in each individual sample these figures also agreed closely. In samples of blood lymphocytes enriched and depleted for E rosettes, results of %E+ also agreed closely with % antigen+ cells. This relationship also held for thymocytes and the specific antibodies could be completely absorbed with thymocytes. These data show that the antibody identified peripheral and thymic E.RFC. Bound to lymphocytes the antibody inhibited E rosette-formation with sheep red blood cells (SRBC) in saline (S) and dextran (DS) and with pig RBC in dextran and in Ficoll, but did not affect B cells shown by immunofluorescence, direct antiglobulin rosette formation or Fc rosette-formation, either in saline or dextran, (which include T gamma cells). E rosette inhibition was dependent on antibody concentration, showing single and double sigmoid curves for S and DS rosettes respectively, consistent with differing ease of inhibition of the strong and weak rosette formation. The same spectrum of inhibition of rosette formation by antibody binding followed subsequent incubation with C'6-deficient rabbit serum, but with C'-sufficient serum resulted in loss of cells which require dextran for Fc rosette-formation (T gamma). Thus the serum reveals E rosette-forming T cells and their subpopulations, perhaps by binding to the SRBC receptor.  相似文献   
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67.
The efficacy of emulsifiable concentrate and dust formulations of pirimiphos-methyl and etrimfos were assessed, when admixed with oilseed rape, 1 day after treatment, against susceptible beetle, moth and mite species. The minimum intended doses required to provide complete mortality differed with each pest species. If Maximum Residue Limits are introduced that are equivalent to less than one quarter of the current pesticide application rates, their effective use may be prevented, as control of Acarus siro and Tyrophagus putrescentiae may not be achieved.  相似文献   
68.
Post‐operative pain management by a single subcutaneous (SC) injection of carprofen has been found to be effective in cats and dogs. This clinical study compared the analgesic properties of injectable carprofen and butorphanol in 71 healthy cats (0.5–5 years, mean weight 3.24 ± 0.61 kg) undergoing ovariohysterectomy. Cats were randomly assigned to three groups: Group C received carprofen 4 mg kg?1 SC at intubation and sterile saline 0.08 mL kg?1 SC at extubation; Group B received sterile saline 0.08 mL kg?1 SC at intubation and butorphanol 0.4 mg kg?1 SC at extubation; Group S received sterile saline 0.08 mL kg?1 SC at intubation and extubation. All cats were pre‐medicated with atropine (0.04 mg kg?1 SC), acepromazine (0.02 mg kg?1 SC), ketamine (5 mg kg?1 SC), and induced IV with ketamine (5 mg kg?1) and diazepam (0.25 mg kg?1). Serum biochemistry values were taken at 24 and 48 hours post‐surgically and compared to a pre‐surgical baseline. Behavioral data were collected by a blinded investigator prior to surgery (baseline) and 1, 2, 3, 4, 8, 12, 16, 20, and 24 hours post‐surgery; the data were compiled into composite pain scores on a scale from 0 to 21 and complemented by visual analogue scores (VAS). Scoring was based on changes in behavior, posture, vocalization, and response to interactive stimulation. Cats with pain scores >12 were considered to be moderately painful, received meperidine (4 mg kg?1 IM), and were excluded from further statistical analyses. Sixty of 71 cats completed the study. Anesthetic time was 88.5 ± 21.8 minutes (mean ± SD). Meperidine was given to one cat in C, three in B, and five in S. There were no significant differences in biochemistry values. There were no significant differences in pain scores between C and B at any time period; B and C pain scores were significantly lower than S at 1, 2, 12, 16, and 20 hours post‐operatively, and C lower than S at 3 and 8 hours post‐surgery. Pain scores decreased over the 24‐hour study in all groups; the greatest decrease in each group was between 4 and 8 hours post‐operatively. In this study, carprofen provided post‐surgical analgesia comparable to butorphanol.  相似文献   
69.
The successful outcome of an insemination is a combination of both male and female fertility‐linked factors. We investigated the first service conception rate of cows at artificial insemination (AI) in the smallholder dairy farms in Bangladesh. Frozen straws were prepared from ejaculates of Bos indicus (n = 7) and Bos indicus × Bos taurus (n = 7) AI bulls. Fertility was determined from 6101 first services in cows that were performed by 18 technicians in four regions between April 2004 and March 2005. Pregnancy was diagnosed by rectal palpation between 60 and 90 days post‐insemination. The Asian version of Artificial Insemination Database Application (AIDA ASIA) was used for bulls‐, cows‐ and AI‐related data recording, and later retrieved for analysis. The mean ± SD number of inseminations performed from individual bulls and their conception rates were 436.0 ± 21.6 and 50.7 ± 1.9%, respectively. Logistic regression demonstrated body condition scores (BCS), heat detection signs, months of AI and their interactions had greatest effects (odds ratios: 1.24–16.65, p < 0.04–0.001) on first service conception rate in cows. Fertility differed (p < 0.02–0.001) between the regions, previous calving months, months of AI, BCS, parity and heat detection signs of cows. Inseminations based on mounting activity (n = 2352), genital discharge (n = 3263) and restlessness and/or other signs (n = 486) yielded a conception rate of 53.6%, 48.8% and 50.1%, respectively (p < 0.05). Conception rate between technicians ranged between 43.4% and 58.6% (p < 0.05). The days interval from calving to first service (overall mean ± SD = 153.4 ± 80.6) had relationship (p < 0.001) with BCS, months of previous calving and parity of the cows. Fertility at AI in smallholder farms can be improved by training farmers on nutrition and reproductive management of the cows.  相似文献   
70.
The potential future earnings and therefore value of Thoroughbred foals untested in the racing arena are calculated based on the performance of their forebears. Thus, lineage is of key importance. However, previous research indicates that maternally inherited mitochondrial DNA (mtDNA) does not correspond to maternal lineage according to recorded pedigree, casting doubt on the voracity of historic pedigrees. We analysed mtDNA of 296 Thoroughbred horses from 33 maternal lineages and identified an interesting trend. Subsequent to the founding of the Thoroughbred breed in the 16th century, well‐populated maternal lineages were divided into sub‐lineages. Only six in 10 of the Thoroughbreds sampled shared mitochondrial haplotype with other members of their maternal lineage, despite having a common maternal ancestor according to pedigree records. However, nine in 10 Thoroughbreds from the 103 sub‐lineages sampled shared mtDNA with horses of their maternal pedigree sub‐lineage. Thus, Thoroughbred maternal sub‐lineage pedigree represents a more accurate breeding record than previously thought. Errors in pedigrees must have occurred largely, though, not exclusively, at sub‐lineage foundation events, probably due to incomplete understanding of modes of inheritance in the past, where maternal sub‐lineages were founded from individuals, related, but not by female descent.  相似文献   
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