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141.
Leukocyte alkaline phosphatase: electrophoretic variants associated with chronic myelogenous leukemia 总被引:1,自引:0,他引:1
Starch-gel electrophoresis of leukocyte alkaline phosphatases, rendered soluble by treating normal leukocytes with butanol, revealed three electrophoretic variants of the enzyme. The phosphatases in similarly prepared extracts of leukemia cells differed from the normal isozymes in electrophoretic. mobility. A single variant was detected in one case of untreated leukemia; a similar component and three additional ones were seen in leukemia treated with 6-mercaptopurine. 相似文献
142.
Tissue concentrations of nitrogen (N) and phosphorus (P) were measured in water hyssop (Bacopa monnieri) subjected to four progressive levels of flooding: well-drained Control, Intermittently Flooded, Partially Flooded, and Continuously Flooded. Soil redox potential (Eh), measured at two levels in the mesocosms decreased under flooding. Flooding increased biomass and decreased root growth and N and P concentrations in shoots, with the decreases being most pronounced in the Partially Flooded and Continuously Flooded treatments. The decreased uptake of N and P under flooding underscores the need to better understand how wetland plants function in nutrient-rich environments subjected to variable flooding. Additionally, the apparent decreased translocation of N and P from the root to the shoot in flooding conditions may be indicative of an overall decrease in mineral transport, which would have implications for the design and management of remediation systems. 相似文献
143.
Nitrate Toxicity to Five Species of Marine Fish 总被引:2,自引:0,他引:2
Richard H. Pierce Jason M. Weeks James M. Prappas 《Journal of the World Aquaculture Society》1993,24(1):105-107
144.
Remotely sensed mesoscale oceanography and the distribution of Illex argentinus in the South Atlantic 总被引:1,自引:0,他引:1
In this study, we consider the influence of mesoscale oceanographic processes around the Falkland Islands (Islas Malvinas) in the South-west Atlantic, during the period in which the commercial squid fishery for Illex argentinus operates. Spatially referenced fishery data and satellite-derived advanced very high resolution radiometry (AVHRR) sea surface temperature (SST) data were examined using geographic information system (GIS) techniques. The distribution and relative abundance of I. argentinus in the Falkland Islands fishery was examined for the period 1989–96. Three consistent areas of high abundance were observed to the north-east (shelf-break region) and north-west (shelf region) of the islands, and close to the northern coast of East Falkland. Areas of high sea surface temperature gradients (thermal gradients) extracted from remotely sensed satellite images were used as an indicator of mesoscale oceanographic activity and compared with the location of the fishery. I. argentinus were found to be associated with areas of thermal gradients, commonly seen at the interface of Falkland Current and Patagonian shelf waters. The techniques used in this analysis allow the overlay and analysis of physical oceanographic and fishery data with potential applications in fisheries management and operational fisheries oceanography. 相似文献
145.
- The short-beaked common dolphin is one of the most numerous cetacean species in the North-East Atlantic and plays a key functional role within the ecosystem as a top predator. However, in 2013, its conservation status for the European Marine Atlantic, under Article 17 of the Habitats Directive, was assessed as ‘Unfavourable-Inadequate’. Of key concern for this species is fishery bycatch, with pollution also being an issue. There are, however, major knowledge gaps concerning the extent of the effects of such pressures on the species.
- Implementation of national observer bycatch programmes and bycatch mitigation measures under EC Regulation 812/2004 has been important. The responsibility for this is currently being transferred to the EU fisheries Data Collection Framework and Technical Measures Framework, the potential advantages and disadvantages of which are discussed. Collection of data and samples through national stranding schemes in some countries has enabled assessments of life-history parameters, dietary requirements, and the effects of stressors such as pollutants.
- Nevertheless, in order to improve the conservation status of the North-East Atlantic population, a number of key actions are still required. These include the implementation of a species action plan, finalization of a management framework procedure for bycatch, and coordination between member states of monitoring programmes. It is important that there is monitoring of the state of the common dolphin population in the North-East Atlantic management unit through regular surveys spanning the range of the management unit, as well as continued assessment of the independent and interactive effects of multiple stressors. Above all, conservation status would be improved through application and enforcement of existing legislation in European waters.
- This paper provides a summary of the current state of our knowledge of common dolphins in the North-East Atlantic along with recommendations for conservation management that may also be relevant to the species in the Mediterranean Sea.
146.
Paleoclimate records indicate that the strength of the Asian summer monsoon is sensitive to orbital forcing at the obliquity and precession periods (41,000 and 23,000 years, respectively) and the extent of Northern Hemisphere glaciation. Over the past 2.6 million years, the timing (phase) of strong monsoons has changed by approximately 83 degrees in the precession and approximately 124 degrees in the obliquity bands relative to the phase of maximum global ice volume (inferred from the marine oxygen isotope record). These results suggest that one or both of these systems is nonstationary relative to orbital forcing. 相似文献
147.
EM Woodward M Christoffersen J Campos DW Horohov KE Scoggin E Squires MHT Troedsson 《Reproduction in domestic animals》2013,48(4):554-561
The first objective of this study was to evaluate intrauterine nitric oxide (NO) and endometrial inducible NO synthase (iNOS) in mares susceptible or resistant to persistent breeding‐induced endometritis (PBIE) within 24 h after breeding. Mares susceptible (n = 6) or resistant (n = 6) to PBIE were inseminated over five cycles, and uterine secretions and endometrial biopsies were collected before and 2, 6, 12 and 24 h after insemination. Uterine secretions were analysed for NO and biopsies were analyzed for iNOS expression. A second experiment evaluated the effect of treatment with dexamethasone or mycobacterial cell wall extract (MCWE) on uterine NO production and endometrial iNOS mRNA expression. Six susceptible mares were inseminated over three cycles with (i) killed spermatozoa without treatment (control), (ii) killed spermatozoa with 50 mg of dexamethasone IV or (iii) MCWE IV 24 h prior to insemination with killed spermatozoa. Six resistant mares were inseminated with killed spermatozoa as a control. Six hours after breeding, uterine biopsies and secretions were collected and evaluated for NO and iNOS mRNA. In Experiment 1, resistant mares had an increase in iNOS mRNA expression 2 h post‐breeding compared to baseline (p = 0.045), 12 h (p = 0.014) and 24 h (p = 0.001). Susceptible mares had higher expression 2 h compared to 6 h (p = 0.046). No differences were observed in mRNA or protein expression of iNOS between resistant and susceptible mares. Resistant mares had a relatively steady amount of total intrauterine NO over 24 h, while susceptible mares had an increase over time, with a significantly higher increase in total NO than resistant mares at 6 (p = 0.04) and 12 h (p = 0.032). In Experiment 2, no differences were observed for iNOS mRNA expression. Susceptible mares had increased NO when compared to resistant mares (p = 0.008) and MCWE decreased NO (p = 0.047). 相似文献
148.
Jeryl C. Jones Thomas J. Tucker Joshua C. Tan Bess J. Pierce Judy L. Foxworth Benjamin Long Tisha A.M. Harper Daniel Moreno 《Journal of Veterinary Behavior: Clinical Applications and Research》2013,8(5):309-315
An improved understanding of the early behavioral indicators of lumbosacral disease in working dogs may allow earlier interventions and help reduce premature retirement because of disability. However, recognition of early behavioral indicators can be challenging in stoic, high-drive working dogs because they often mask clinical signs. The purpose of this feasibility study was to develop a technique for visualizing canine skeletal movements during working tasks and to describe veterinary clinical specialist opinions on the utility of the visualization technique. Three detection-trained police dogs with a recent history of working task deficits and suspected lumbosacral disease were recruited for the study. Conventional and motion capture video recordings were acquired as dogs performed walking and search high working tasks. Whole-body computed tomography (CT) scans were acquired using clinical multislice CT scanners. Image data from motion capture recordings and whole-body CT scans were analyzed and merged. Three-dimensional (3D) computer animation video clips of skeletal movements were created for each dog and each task, using multiple viewing angle perspectives. Interactive meetings with veterinary clinical specialist reviewers were used to refine point placements for the final renderings. Veterinary clinical specialists reviewed final 3D animation movie clips and recorded their opinions on the utility for the visualization technique. Veterinary clinical specialists reported that the computer animations helped them recognize behavioral characteristics that they had not initially noticed in physical examinations. Potential applications for this visualization technique include creating educational training aids for veterinary students, owners, and handlers; assisting veterinarians in planning rehabilitative treatments; and assisting researchers in developing computer models for biomechanical analyses. Future controlled prospective studies are needed in a large number of normal and affected working dogs to improve accuracy of the visualization technique and test the effect of the technique on observer performance. 相似文献
149.
José L. Chávez Francis J. Pierce Todd V. Elliott Robert G. Evans 《Precision Agriculture》2010,11(1):1-10
Continuous move irrigation systems have been modified since the 1990s to support variable rate irrigation. Most of these systems
used PLC (Programmable Logic Controllers) technology that performed well for on-site control but were very expensive to add
remote, real-time monitoring and control aspects that have been made possible by wireless sensor networks and the Internet.
A new approach to the monitoring and control of continuous move irrigation systems is described. This system uses a Single
Board Computer (SBC) using the Linux operating system to control solenoids connected to individual or groups of nozzles based
on prescribed application maps. The main control box houses the SBC connected to a sensor network radio, a GPS (Global Positioning
System) unit, and an Ethernet radio creating a wireless connection to a remote server. A C-software control program resides
on the SBC to control the on/off time for each nozzle group using a “time on” application map developed remotely. The SBC
also interfaces with the sensor network radio to record measurements from sensors on the irrigation system and in the field
that monitor performance and soil and crop conditions. The SBC automatically populates a remote database on the server in
real time and provides software applications to monitor and control the irrigation system through the Internet. 相似文献
150.
Rebecca L. Pierce BVetMed Andrew T. Fischer DVM Diplomate ACVS Barton W. Rohrbach VMD MPH Dipolmate ACVPM Andreas Klohnen DVM Diplomate ACVS 《Veterinary surgery : VS》2010,39(5):609-615
Objective: To compare incidence of postoperative complications and survival of horses that had surgery for enterolithiasis of the ascending (AC) or descending (DC) colon. Study design: Case series Animals: Horses (n=236) that had celiotomy for AC (n=97) or DC (n=139) enterolithiasis. Methods: Medical records (1999–2005) were reviewed for signalment, presenting clinical signs, surgical findings, postoperative complications, and short‐term survival until discharge. Information on performance and survival ≥1 year was obtained by telephone or mailed questionnaire. Results: Number of postoperative complications did not differ between groups (P=.76). The most frequently identified short‐term complications for all horses were incisional problems, gastric ulceration, ileus, diarrhea, fever, and anorexia. Horses with DC enteroliths had a significantly higher incidence of anorexia (P=.04) and fever (P=.01). The most common complications after hospital discharge were incisional problems, laminitis, weight loss, and colic. Although more DC horses were euthanatized intraoperatively (P=.02), no differences were detected for horses that survived until discharge (P=.18) or ≥1 year after discharge (P=.47). Conclusions: Number or type of postsurgical complications or survival after surgery was not influenced by enterolith location and horses have a favorable prognosis for long‐term survival after enterolith removal, regardless of site of obstruction in the colon. Clinical Relevance: Incidence of postoperative complications and survival are not affected by the site of enterolith obstruction in the colon. 相似文献