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991.
Propagation of subtropical eucalypts is often limited by low production of rooted cuttings in winter. This study tested whether changing the temperature of Corymbia citriodora and Eucalyptus dunnii stock plants from 28/23°C (day/night) to 18/13°C, 23/18°C or 33/28°C affected the production of cuttings by stock plants, the concentrations of Ca and other nutrients in cuttings, and the subsequent percentages of cuttings that formed roots. Optimal temperatures for shoot production were 33/28°C and 28/23°C, with lower temperatures reducing the number of harvested cuttings. Stock plant temperature regulated production of rooted cuttings, firstly by controlling shoot production and, secondly, by affecting the ensuing rooting percentage. Shoot production was the primary factor regulating rooted cutting production by C. citriodora, but both shoot production and root production were key determinants of rooted cutting production in E. dunnii. Effects of lower stock plant temperatures on rooting were not the result of reduced Ca concentration, but consistent relationships were found between adventitious root formation and B concentration. Average rooting percentages were low (1–15% for C. citriodora and 2–22% for E. dunnii) but rooted cutting production per stock plant (e.g. 25 for C. citriodora and 52 for E. dunnii over 14 weeks at 33/28°C) was sufficient to establish clonal field tests for plantation forestry.  相似文献   
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Extract

It is with considerable regret that we record the death, as result of a car accident, of David Stewart Christopher, aged 35, on 11th December, 1985. David was born in Te Awamutu and attended the local Kihikihi Primary School and Te Awamutu College. David was a skilled sportsman, being a member of the 1st XV and 1st XI at College. David left school without completing his University Entrance and worked on his father's farm for a year before completing the exam by correspondence. David then gained his veterinary degree at Massey University, completing this in 1974.  相似文献   
995.
MicroRNAs (miRNAs) are important regulators of gene expression and are known to play a key role in regulating both adaptive and innate immunity. Bovine alveolar macrophages (BAMs) help maintain lung homeostasis and constitute the front line of host defense against several infectious respiratory diseases, such as bovine tuberculosis. Little is known, however, about the role miRNAs play in these cells. In this study, we used a high-throughput sequencing approach, RNA-seq, to determine the expression levels of known and novel miRNAs in unchallenged BAMs isolated from lung lavages of eight different healthy Holstein–Friesian male calves. Approximately 80 million sequence reads were generated from eight BAM miRNA Illumina sequencing libraries, and 80 miRNAs were identified as being expressed in BAMs at a threshold of at least 100 reads per million (RPM). The expression levels of miRNAs varied over a large dynamic range, with a few miRNAs expressed at very high levels (up to 800,000 RPM), and the majority lowly expressed. Notably, many of the most highly expressed miRNAs in BAMs have known roles in regulating immunity in other species (e.g. bta-let-7i, bta-miR-21, bta-miR-27, bta-miR-99b, bta-miR-146, bta-miR-147, bta-miR-155 and bta-miR-223). The most highly expressed miRNA in BAMs was miR-21, which has been shown to regulate the expression of antimicrobial peptides in Mycobacterium leprae-infected human monocytes. Furthermore, the predicted target genes of BAM-expressed miRNAs were found to be statistically enriched for roles in innate immunity. In addition to profiling the expression of known miRNAs, the RNA-seq data was also analysed to identify potentially novel bovine miRNAs. One putatively novel bovine miRNA was identified. To the best of our knowledge, this is the first RNA-seq study to profile miRNA expression in BAMs and provides an important reference dataset for investigating the regulatory roles miRNAs play in this important immune cell type.  相似文献   
996.
An approximately 8‐year‐old male castrated Dutch rabbit was evaluated for a 6‐day history of respiratory signs, which began as sneezing and progressed to tachypnea with anorexia. On physical examination, tachypnea and pale mucous membranes were noted. Thoracic radiographs revealed a soft tissue pulmonary mass, fine‐needle aspirates of which confirmed a neoplasia with malignant features suspicious for a histiocytic sarcoma. The rabbit was discharged and due to a rapidly deteriorating condition, the owner declined chemotherapy with Lomustine and elected euthanasia of the rabbit. The affected lung was submitted for histopathology. Histologic sections of the lung were characterized by clusters of histiocytic cells and multinucleated giant cells with occasional invasion of blood and lymphatic vessels. The histologic diagnosis was histiocytic sarcoma. To the authors' knowledge, this is the first case report of histiocytic sarcoma in a rabbit. Based on the clinical and radiologic findings in this case, histiocytic sarcoma should be included in the list of differentials for rabbits presenting with respiratory signs and evidence of a pulmonary mass.  相似文献   
997.
Interest is growing in the relocalization of staple crops, including wheat, in western Washington (WWA), a nontraditional wheat-growing area. Commercial bakers are potentially important food chain intermediaries in the case of relocalized wheat production. We conducted a mail survey of commercial bakers in WWA to assess their interest in sourcing wheat/flour from WWA, identify the characteristics of bakeries most likely to purchase wheat/flour from WWA, understand the factors important to bakers in purchasing regionally produced wheat/flour, and identify perceived barriers to making such purchases. Sixty-one percent of survey respondents were interested in purchasing WWA wheat/flour. Bakers who used retail strategies to market their products were more likely to be interested in WWA wheat/flour compared to those not using retail methods. Bakers’ current purchases of Washington wheat/flour were not related to their interest in purchasing WWA flour. The most important factors bakers would consider in purchasing regionally produced wheat/flour were consistency of flour quality, quality of flour, and reliability of supply. Cost was the most frequently mentioned barrier to the purchase of regionally produced wheat/flour. Our results are relevant for other areas attempting to reconnect grain producers, commercial bakers, and consumers in mutually beneficial ways.  相似文献   
998.
Molothrus属的5种牛鹂中,褐头牛鹂(Molothrus ater)是唯一一种在北美广泛分布和常见的寄生性繁殖的牛鹂。褐头牛鹂主要见于开阔地和林缘,为泛性寄生且进化历史较晚,因此其与宿主之间的协同进化适应远不如其他鸟类巢寄生系统。由于褐头牛鹂能广泛寄生各种潜在的宿主鸟类,很可能导致一些濒危鸟类的灭绝,这引起了人们对这一寄生牛鹂的高度关注,而如何控制这一鸟类,也成为保护生物学的一个热点问题。  相似文献   
999.
Although the importance of coenzyme Q10 (CoQ10) in health and disease and its critical role in cellular bioenergetics have been well established in various species, there is a total lack of information on the role of CoQ10 in horses. Therefore, the present study was undertaken first to ascertain the occurrence of CoQ10 and/or possibly other homologs of coenzyme Q (CoQ) in horse serum, and then to examine the response to CoQ10 supplementation on serum CoQ10 concentration. The study was carried out with 2-year-old Thoroughbred horses. Total CoQ (reduced and oxidized forms) in serum was assayed by high-performance liquid chromatography. The data show that horse serum contains CoQ as CoQ10, at a much lower concentration as compared with that of humans and several other species. There is no evidence for the presence of coenzyme Q9 or other homologs of CoQ. On supplementation with CoQ10 at 800 mg a day (1.47 mg/kg body weight), there was a significant increase in serum CoQ10 concentration, approximately 2.7-fold at 60 days. CoQ10 supplementation at this dosage was found to be safe and well tolerated. Additional studies are needed to examine whether maintaining higher serum CoQ10 concentrations is of potential health benefit to the horses, as assessed by selected biochemical markers and also in terms of performance.  相似文献   
1000.
This study examined the immunological responses of pregnant cattle and their foetuses following an experimental challenge with live Neospora caninum tachyzoites at day 210 of gestation. Animals were bled prior to and weekly throughout the experiment and sacrificed at 14, 28, 42 and 56 days post inoculation (dpi). At post mortem examination, samples of lymph nodes and spleen were collected from both dam and foetus for immunological analysis. Subcutaneous (sc) inoculation over the left prefemoral (LPF) lymph node of pregnant cattle at day 210 of gestation, led to the vertical transmission of parasites by 14 dpi, however no foetal deaths were observed in the infected animals. Foetuses from infected dams mounted Neospora-specific humoral and cell-mediated immune (CMI) responses by 14 dpi. These responses involved anti-Neospora IgG, antigen-specific lymphocyte proliferation, and the production of the cytokines IFN–γ, interleukin (IL)-4 and IL-10. There was also evidence of innate immunity during the response against Neospora from infected dams, with statistically significant (p < 0.05) increases in mean expression of toll like receptors (TLR)-2 on 56 dpi in maternal spleen, LPF, right prefemoral (RPF), left uterine (LUL) and right uterine (RUL) lymph nodes and TLR-9 in retropharyngeal (RLN), LPF and RPF lymph nodes from 28 dpi. Statistically significant (p < 0.05) increases in mean TLR-9 were detected in spleen samples from foetuses of infected dams, compared to the foetuses from control animals. Our results show that vertical transmission of the parasite occurred in all infected dams, with their foetuses showing effective Neospora-specific cell mediated, humoral and innate immune responses.  相似文献   
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