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991.
Both entrepreneurship and foreign direct investment (FDI) are frequently identified as being sources of local and regional economic growth. However, the relationship between the two is not always clear, with a negative competition effect and a positive demand effect potentially present. China provides an interesting case to study with its large state-owned sector, combined with a recent history of successfully attracting considerable FDI. This study examines the relationship between self-employment and different elements of foreign influence (FI) at a provincial level. The results imply that foreign investment reduces the level of self-employment, whilst the number of foreign enterprises and foreign exports have positive effects. The results therefore show the importance in considering multiple perspectives in terms of FI. It appears that policies that attract individual large investments suppress the development of domestic enterprise as predicted by the competition effect, but where more foreign enterprises are present, and a cluster starts to develop, a demand effect appears to take over. This means that provincial government policy may need to be more nuanced to avoid economies being highly reliant on a limited number of what might be quite footloose larger foreign employers.  相似文献   
992.
  • 1. Assessments of anthropogenic impacts on cetaceans are often constrained by limited data on the extent to which these species use particular areas.
  • 2. Timing porpoise detectors (T‐PODs) are autonomous data recorders for detecting cetacean echolocation clicks, potentially providing cost‐effective opportunities for monitoring cetacean occurrence.
  • 3. The performance of T‐PODs was assessed in three areas off the Scottish east coast, where the relative occurrence of bottlenose dolphins and harbour porpoises was known to differ. Land‐based observations in one area compared visual and acoustic detections of dolphins, while direct hydrophone recordings of dolphin echolocation clicks were compared with T‐POD detections during boat surveys.
  • 4. Land‐based surveys recorded 89 groups of dolphins within 900 m of the T‐POD. All groups spending >30 min in the area were detected on the T‐POD, and the probability of detection declined in relation to distance from the recording site.
  • 5. The number of dolphin clicks recorded on the independent hydrophone system was significantly related to the number detected by a T‐POD. Between pairs of T‐PODs, there was also significant correlation with the numbers of clicks recorded in each hour, both for channels set to detect bottlenose dolphins and for channels set to detect harbour porpoises.
  • 6. Year‐round deployments of paired T‐PODs detected significant geographical variation in detections for both bottlenose dolphins and harbour porpoises. This pattern reflected published data from visual surveys, where dolphins occurred most regularly within the Moray Firth Special Area of Conservation, and porpoises were sighted more regularly in offshore waters.
  • 7. T‐PODs do not detect all cetaceans in the area, and care must be taken when interpreting data from mixed species communities. Nevertheless, these results confirm that T‐PODs provide an effective method for monitoring the occurrence of bottlenose dolphins and harbour porpoises, and provide excellent potential for collecting baseline data from poorly studied areas and monitoring long‐term temporal change in key areas of interest. Copyright © 2009 John Wiley & Sons, Ltd.
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Groupers are popular aquaculture species in South-East Asia, but their cultivation is affected by infectious disease outbreaks. Mucosa-associated lymphoid tissues provide a first-line defence against pathogens; however, few studies are available relating to cellular or proteomic responses of mucosal immunity in grouper. Skin, gill and intestine were sampled from brown-marbled grouper Epinephelus fuscoguttatus (Forsskål, 1775) at 4 and 96 hr post-infection (hpi) and 7 days post-infection (dpi) following intraperitoneal infection with Vibrio harveyi, and stained with haematoxylin/eosin and Alcian Blue/periodic acid–Schiff. Skin mucus was analysed by 2D-gel electrophoresis, and proteins modulated by the bacterial infection identified. In the infected fish, significant increases in sacciform cells in skin and increased levels of nucleoside diphosphate kinase in mucus were detected at 4 hpi. At 96 hpi, goblet cells containing acidic mucins significantly increased in the intestine, while those containing mixed mucins increased in skin and gills of infected fish. Proteasome subunit alpha type-I and extracellular Cu/Zn superoxide dismutase levels also increased in mucus. Rodlet and mast cells did not appear to respond to the infection. Mucosal tissues of grouper appeared actively involved in response to Vibrio infection. This information may help future research on improving grouper health, production and vaccine development.  相似文献   
996.
Marine heatwaves are increasingly affecting marine ecosystems, with cascading impacts on coastal economies, communities, and food systems. Studies of heatwaves provide crucial insights into potential ecosystem shifts under future climate change and put fisheries social-ecological systems through “stress tests” that expose both vulnerabilities and resilience. The 2014–16 Northeast Pacific heatwave was the strongest and longest marine heatwave on record and resulted in profound ecological changes that impacted fisheries, fisheries management, and human livelihoods. Here, we synthesize the impacts of the 2014–2016 marine heatwave on US and Canada West Coast fisheries and extract key lessons for preparing global fisheries science, management, and industries for the future. We set the stage with a brief review of the impacts of the heatwave on marine ecosystems and the first systematic analysis of the economic impacts of these changes on commercial and recreational fisheries. We then examine ten key case studies that provide instructive examples of the complex and surprising challenges that heatwaves pose to fisheries social-ecological systems. These reveal important insights into improving the resilience of monitoring and management and increasing adaptive capacity to future stressors. Key recommendations include: (1) expanding monitoring to enhance mechanistic understanding, provide early warning signals, and improve predictions of impacts; (2) increasing the flexibility, adaptiveness, and inclusiveness of management where possible; (3) using simulation testing to help guide management decisions; and (4) enhancing the adaptive capacity of fishing communities by promoting engagement, flexibility, experimentation, and failsafes. These advancements are important as global fisheries prepare for a changing ocean.  相似文献   
997.
The primary purpose of this experiment was to assess the possible beneficial effects of recombinant equine somatotropin (reST) administration on wound healing in adult geldings. The effects of the 21-d reST treatment on carbohydrate and lipid metabolism and on endogenous ST characteristics were monitored as well. Single, full-thickness skin incisions (7.62 x 7.62 cm) were made in the pectoral region of all geldings on d 0. Treated geldings received reST at 20 microg/kg BW i.m., and control geldings received vehicle (10 mM sodium borate) at equivalent volumes daily from d 0 (immediately after surgery) through d 20. Tracings of the wounds were made with acetate transparencies, and wound areas were calculated via a digital analyzer. In addition to once-daily blood samples collected at specified days throughout the treatment period, an i.v. glucose tolerance test was performed on d 16, and three assessments of endogenous ST secretion were performed in the 2 d immediately following the end of treatment: epinephrine administration during the morning of d 21, an exercise test during the afternoon of d 21, and i.v. aspartic acid infusion on d 22. There was no effect (P > . 1) of reST treatment on wound healing as assessed by changes in wound areas. Daily plasma ST, IGF-I, glucose, and insulin concentrations were higher (P < .05) and urea-nitrogen concentrations were lower (P < .001) in geldings receiving reST relative to controls. Glucose, NEFA, and insulin concentrations were all higher (P < .01) in reST-treated geldings before glucose infusion on d 16, and the responses to glucose were greater (P < .05) as well. Epinephrine administration increased (P < .02) ST concentrations in control geldings on d 21 but not in reST-treated geldings; a similar suppressive effect of reST treatment was observed for the ST response to exercise (P < .001). After aspartic acid infusion on d 22, reST-treated geldings had a much smaller (P < .001) ST response than did control geldings. In conclusion, reST administered to geldings at 20 microg/kg BW i.m. caused hyperglycemia, hyperinsulinemia, insulin insensitivity, mobilization of fatty acids, and an apparent negative feedback on the pituitary's ST response to various stimuli known to induce ST secretion. However, there was no beneficial effect of reST treatment with the wound model used in this experiment.  相似文献   
998.
ABSTRACT: Cycling (n = 16) and noncycling (n = 24), early postpartum, suckled beef cows of three breeds were assigned randomly to three treatments: 1) 100-microg injection of GnRH plus a 6-mg implant of norgestomet administered on d -7 before 25 mg of PGF2alpha and implant removal on d 0 (GnRH+NORG); 2) 100 microg of GnRH given on d -7 followed by 25 mg of PGF2alpha on d 0 (GnRH); or 3) 2 mL of saline plus a 6-mg implant of norgestomet administered on d -7 followed by 25 mg of PGF2, and implant removal on d 0 (NORG). All cows were given 100 microg of GnRH on d +2 (48 h after PGF2alpha). Blood sera collected daily from d -7 to d +4 were analyzed for progesterone and estradiol-17beta, and ovaries were monitored daily by transrectal ultrasonography to assess changes in ovarian structures. Luteal structures were induced in 75% of noncycling cows in both treatments after GnRH, resulting in elevated (P < .01) progesterone on d 0 for GnRH+NORG-treated cows. Concentrations of estradiol-17beta (P < .01) and LH (P < .05) were greater on d +2 after GnRH for cows previously receiving norgestomet implants. Pregnancy rates after one fixed-time AI at 16 h after GnRH (d +2) were greater (P < .05) in GnRH+NORG (71%) than in GnRH (31%) and NORG (15%) cows. Difference in pregnancy rate was due partly to normal luteal activity after AI in over 87% of GnRH+NORG cows and no incidence of short luteal phases. The GnRH+NORG treatment initially induced ovulation or turnover of the largest follicle, induction of a new follicular wave, followed later by increased concentrations of estradiol-17beta and progesterone. After PGF2alpha, greater GnRH-induced release of LH occurred in GnRH+NORG cows before ovulation, and pregnancy rates were greater after a fixed-time AI.  相似文献   
999.
A study was conducted to investigate the persistent nematocidal activity of two avermectins against experimentally-induced infections of Ascaris suum in swine. Seventy-two nematode-free cross-bred pigs of similar bodyweight were randomly allotted to nine treatment groups of eight pigs each. Eight of the groups were treated with injectable solutions containing 300 microg of doramectin/kg (IM) or 300 microg of ivermectin/kg (SC) either 0 (same day), 7, 14, or 21 days prior to an oral challenge of 50000 embryonated A. suum eggs. The ninth group (control) was challenged in parallel without any avermectin treatment. At 41 or 42 days after challenge, pigs were euthanatized and adult and larval stages of A. suum were collected from the gastrointestinal tract of each pig and counted. Both avermectins significantly (P < 0.0002) reduced nematode counts when given on the day of challenge (0 days prior), and the efficacy was 100% and 97.5% for doramectin and ivermectin, respectively. Doramectin given 7 days prior to challenge significantly (P < 0.0001) reduced nematode counts, and the efficacy was 98.4%. For all other avermectin-treatment groups, nematode counts were not significantly reduced compared to those in control pigs. These data indicated that anthelmintic activity of ivermectin against A. suum persisted for less than 7 days and the activity of doramectin persisted for more than 7, but less than 14 days.  相似文献   
1000.
Two Santa Gertrudis cattle from a herd of 105 aborted within a 24-hour period. Bacteroides fragilis was isolated from tissues of each aborted fetus. Histopathologic lesions included placentitis and bronchopneumonia in which gram-negative, rod-shaped organisms were visible. The diagnostic workup failed to reveal other causes of abortion. Anaerobes are rarely implicated in bovine abortions, and no other report was found that described abortion in cattle due to B. fragilis.  相似文献   
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