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41.
Smith R Thomas JS 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2002,31(1):26-32
Background — Thrombocytopenia is a common disorder in dogs and development of an objective diagnostic assay to measure platelets newly released from bone marrow into the blood would provide a noninvasive way to predict megakaryocytopoiesis. Reticulated platelets are newly released platelets with increased concentrations of RNA that can be detected by flow cytometric analysis of blood stained with thiazole orange (TO).
Objectives — The goals of this study were to establish a reproducible method to quantitate reticulated platelets in dogs, to establish a reference interval for reticulated platelet percentages in healthy dogs, and to determine whether the percentage of reticulated platelets was nonspecifically increased in nonthrombocytopenic dogs with clinical disease.
Methods — Blood samples were obtained from healthy dogs and from nonthrombocytopenic dogs presented for a variety of disorders. An aliquot of whole blood was stained with TO and a phycoerythrin-labeled monoclonal antibody to platelet CD61, then analyzed by flow cytometry.
Results — The coefficients of variation were 7.8% to 15.6% (intra-assay precision) and 6.1% to 19.5% (interassay precision). Overnight storage for 18 to 26 hours, under variable conditions, resulted in an increase in the percentage of platelets staining with TO. The reference interval for reticulated platelets in the healthy control group was 0–4.3% (0–12,095/μL). No significant differences were found in the mean percentage of reticulated platelets or absolute concentration of reticulated platelets between control and affected dogs.
Conclusions — These studies demonstrate a reliable, noninvasive diagnostic assay for measurement of reticulated platelets in whole blood and provide a baseline for assessment of the clinical utility of the assay. 相似文献
Objectives — The goals of this study were to establish a reproducible method to quantitate reticulated platelets in dogs, to establish a reference interval for reticulated platelet percentages in healthy dogs, and to determine whether the percentage of reticulated platelets was nonspecifically increased in nonthrombocytopenic dogs with clinical disease.
Methods — Blood samples were obtained from healthy dogs and from nonthrombocytopenic dogs presented for a variety of disorders. An aliquot of whole blood was stained with TO and a phycoerythrin-labeled monoclonal antibody to platelet CD61, then analyzed by flow cytometry.
Results — The coefficients of variation were 7.8% to 15.6% (intra-assay precision) and 6.1% to 19.5% (interassay precision). Overnight storage for 18 to 26 hours, under variable conditions, resulted in an increase in the percentage of platelets staining with TO. The reference interval for reticulated platelets in the healthy control group was 0–4.3% (0–12,095/μL). No significant differences were found in the mean percentage of reticulated platelets or absolute concentration of reticulated platelets between control and affected dogs.
Conclusions — These studies demonstrate a reliable, noninvasive diagnostic assay for measurement of reticulated platelets in whole blood and provide a baseline for assessment of the clinical utility of the assay. 相似文献
42.
Christy A McKnight Annabel G Wise Roger K Maes Christopher Howe Annabel Rector Marc Van Ranst Matti Kiupel 《Journal of zoo and wildlife medicine》2006,37(2):193-196
A 5-yr-old female Egyptian fruit bat (Rousettus aegyptiacus) had a small raised pigmented mass removed from the lateral canthus of the left eye. Six additional variably sized, raised, smooth to cauliflower-like skin masses were observed randomly distributed throughout the left wing membranes. Four masses were removed and diagnosed microscopically as basosquamous carcinomas and papillomas. Additional masses, removed 6 mo and 1 yr later, showed bony invasion and squamous differentiation. Immunohistochemistry detected positive intranuclear staining for bovine papillomavirus antibody in all samples. Polymerase chain reaction done on DNA extracts from formalin-fixed, paraffin-embedded tumor tissue amplified a 450 base-pair segment analogous to the L1 region of human papillomavirus types 96 and 5. Basic Local Alignment Search Tool analysis of sequenced amplicons suggests a novel chiropteran papillomavirus. To our knowledge, this is the first report of papillomavirus-associated carcinoma in a chiropteran species. 相似文献
43.
44.
Nickolee Zollinger Roger Kjelgren Teresa Cerny-Koenig Kelly Kopp Rich Koenig 《Scientia Horticulturae》2006
Although low water use landscaping is becoming common in arid regions, little is known about drought tolerance and drought responses of many ornamental plants, especially herbaceous perennials. Drought responses were assessed for six herbaceous ornamental landscape perennials in a 38 l pot-in-pot system in northern Utah over a 2-year period. The first year was an establishment period. During the second year, drought responses were evaluated for established Echinacea purpurea (L.) Moench, Gaillardia aristata Pursh, Lavandula angustifolia P. Mill., Leucanthemum × superbum (J.W. Ingram) Berg. ex Kent, ‘Alaska’, Penstemon barbatus Roth var. praecox nanus rondo, and Penstemon × mexicali Mitch. ‘Red Rocks’. Plants were irrigated at frequencies of 1 (control), 2, or 4 weeks between June and September, simulating well-watered conditions, moderate drought, or severe drought. Osmotic potential (Ψs), gas exchange, visual quality, leaf area, and dry weight were assessed. In a confined root zone, P. barbatus showed the greatest tolerance to all levels of drought, avoiding desiccation by increasing root:shoot ratio and decreasing stomatal conductance as water became limiting. L. angustifolia and P. × mexicali showed tolerance to moderate drought conditions, but died after exposure to the first episode of severe drought. Neither G. aristata nor L. superbum were able to regulate shoot water loss effectively. Instead, both species displayed drought avoidance mechanisms, dying back when water was limiting and showing new growth after they were watered. Compared to control plants, G. aristata shoot dry weight was reduced by 50% and 84%, and L. superbum shoot dry weight was reduced by 47% and 99% for the 2- and 4-week irrigation intervals, respectively. Root dry weights were affected similarly for both species. E. purpurea exhibited poor visual quality at all irrigation intervals, in particular wilting severely in both drought treatments, but regaining turgor when watered again. P. barbatus is recommended for ornamental landscapes that receive little or no supplemental irrigation, while E. purpurea is not recommended for low water landscapes because of low visual quality under even mild drought. 相似文献
45.
Protocol: a highly sensitive RT-PCR method for detection and quantification of microRNAs 总被引:5,自引:0,他引:5
Erika Varkonyi-Gasic Rongmei Wu Marion Wood Eric F Walton Roger P Hellens 《Plant methods》2007,3(1):12
MicroRNAs (miRNAs) are a class of small non-coding RNAs with a critical role in development and environmental responses. Efficient
and reliable detection of miRNAs is an essential step towards understanding their roles in specific cells and tissues. However,
gel-based assays currently used to detect miRNAs are very limited in terms of throughput, sensitivity and specificity. Here
we provide protocols for detection and quantification of miRNAs by RT-PCR. We describe an end-point and real-time looped RT-PCR
procedure and demonstrate detection of miRNAs from as little as 20 pg of plant tissue total RNA and from total RNA isolated
from as little as 0.1 μl of phloem sap. In addition, we have developed an alternative real-time PCR assay that can further
improve specificity when detecting low abundant miRNAs. Using this assay, we have demonstrated that miRNAs are differentially
expressed in the phloem sap and the surrounding vascular tissue. This method enables fast, sensitive and specific miRNA expression
profiling and is suitable for facilitation of high-throughput detection and quantification of miRNA expression. 相似文献
46.
南方菜豆花叶病毒(SBMV)主要有2株系:菜豆株系(SBMV-B)和豇豆株系(SBMV-C),血清学方法不能予以区分。根据已报道的核酸序列设计了2对特异引物,进行RT-PCR扩增并克隆到载体Bluescript中,序列测定予以证实后利用随机引物法合成放射性cDNA探针,再进行体外转译合成地高辛UTP标记的RNA探针。2种探针均可分别特异地检测Northernblot膜上的SBMV-B和SBMV-C。RNA探针检测SBMV-B和SBMV-C灵敏度分别为:0.1μg和0.01μg。 相似文献
47.
Tropical Animal Health and Production - 相似文献
48.
49.
Tissue DT Lewis JD Wullschleger SD Amthor JS Griffin KL Anderson OR 《Tree physiology》2002,22(15-16):1157-1166
Trees exposed to elevated CO2 partial pressure ([CO2]) generally show increased rates of photosynthesis and growth, but effects on leaf respiration are more variable. The causes of this variable response are unresolved. We grew 12-year-old sweetgum trees (Liquidambar styraciflua L.) in a Free-Air CO2 Enrichment (FACE) facility in ambient [CO2] (37/44 Pa daytime/nighttime) and elevated [CO2] (57/65 Pa daytime/nighttime) in native soil at Oak Ridge National Environmental Research Park. Nighttime respiration (R(N)) was measured on leaves in the upper and lower canopy in the second (1999) and third (2000) growing seasons of CO2 fumigation. Leaf respiration in the light (R(L)) was estimated by the technique of Brooks and Farquhar (1985) in the upper canopy during the third growing season. There were no significant short-term effects of elevated [CO2] on R(N) or long-term effects on R(N) or R(L), when expressed on an area, mass or nitrogen (N) basis. Upper-canopy leaves had 54% higher R(N) (area basis) than lower-canopy leaves, but this relationship was unaffected by CO2 growth treatment. In August 2000, R(L) was about 40% of R(N) in the upper canopy. Elevated [CO(2)] significantly increased the number of leaf mitochondria (62%), leaf mass per unit area (LMA; 9%), and leaf starch (31%) compared with leaves in ambient [CO(2)]. Upper-canopy leaves had a significantly higher number of mitochondria (73%), N (53%), LMA (38%), sugar (117%) and starch (23%) than lower-canopy leaves. Growth in elevated [CO2] did not affect the relationships (i.e., intercept and slope) between R(N) and the measured leaf characteristics. Although no factor explained more than 45% of the variation in R(N), leaf N and LMA were the best predictors for R(N). Therefore, the response of RN to CO2 treatment and canopy position was largely dependent on the magnitude of the effect of elevated [CO2] or canopy position on these characteristics. Because elevated [CO2] had little or no effect on N or LMA, there was no effect on R(N). Canopy position had large effects on these leaf characteristics, however, such that upper-canopy leaves exhibited higher R(N) than lower-canopy leaves. We conclude that elevated [CO2] does not directly impact leaf respiration in sweetgum and that barring changes in leaf nitrogen or leaf chemical composition, long-term effects of elevated [CO2] on respiration in this species will be minimal. 相似文献
50.
Evaluation of existing on-farm agroforestry plots should provide useful supplementary information for the design of improved agroforestry systems, in both research and development projects. Such evaluation has been little used, however, largely due to the methodological difficulties of surveying highly variable on-farm plots, and difficulties in identifying key variables for measurement. This paper describes a set of methods and tools used in evaluating plots of alley-cropping and tree borders around crop fields established by farmers working with the CARE Agroforestry Extension Project in western Kenya. Details of survey design, sampling, and implementation are discussed, and suggestions made for carrying out agroforestry surveys in other projects. A condensed version of the questionnaire is appended. 相似文献