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981.
982.
Eurasian Soil Science - Data on concentrations and distribution of tritium in soils of the “Atomic” Lake excavation explosion area of Semipalatinsk Nuclear Test Site (Kazakhstan, East...  相似文献   
983.
984.
    
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985.
    
OBJECTIVE: To evaluate the clinical, cerebrospinal fluid (CSF), and histopathologic effects of epidural ketorolac. STUDY DESIGN: Blinded, randomized, placebo controlled study. ANIMALS: Twenty-two adult mixed breed dogs with 16 treatment and 6 control dogs, weighing 14.4 to 29.8 kg. METHODS: Dogs were anesthetized and epidural catheters were placed at the lumbosacral space. Catheter placement was evaluated fluoroscopically. Ketorolac (0.4 mg/kg) or placebo (5% ethanol) was administered epidurally over a 52-hour period, with 5 injections given at 12-hour intervals. At 1, 2, 4, or 8 hours after the first and last injection of ketorolac, dogs were anesthetized and CSF was obtained. Control dogs had CSF sampled 1 hour after the first and last ethanol injection. Neurologic function and pain responses were evaluated before and during the study. Selected dogs were then killed and necropsies performed. RESULTS: None of the dogs exhibited any clinical or neurologic abnormalities during the study. No statistical difference was noted in pain response or CSF analysis between treatment and control dogs. Gross necropsy revealed gastrointestinal ulceration of varying degrees in all treatment dogs. Histopathologic analysis of the spinal cord and meninges revealed minimal focal leptomeningeal phlebitis in 2 of 8 treatment dogs and minor subdural inflammation in 1 control dog. No changes to the neural structures were noted in any dogs. CONCLUSIONS: Epidural administration of ketorolac did not cause clinical signs, alteration in CSF values, or pathologic changes to the spinal cord when used for short duration. Gastrointestinal ulceration was common when ketorolac was administered epidurally at 0.4 mg/kg every 12 hours for 5 treatments. CLINICAL RELEVANCE: This study documented the neurologic safety of epidural ketorolac in dogs before an efficacy trial can be performed. Gastrointestinal ulceration may limit use to short duration or a single injection.  相似文献   
986.
    
Reasons for performing study: The equine temporomandibular joint (TMJ) and its surrounding structures can be difficult to investigate in cases with a clinical problem related to the region. Little previous attention has been given either to a computed tomographic (CT) imaging protocol for the joint or an interpretation of the structures displayed in CT images of the normal joint. Objectives: To provide a CT atlas of the normal cross‐sectional anatomy of the equine TMJ using frozen and plastinated sections as anatomical reference. Methods: Eight TMJs from 4 immature pure‐bred Spanish horses were examined by helical CT. Scans were processed with a detailed algorithm to enhance bony and soft tissue. Transverse CT images were reformatted into sagittal and dorsal planes. Transverse, sagittal and dorsal cryosections were then obtained, photographed and plastinated. Relevant anatomic structures were identified in the CT images and corresponding anatomical sections. Results: In the CT images, a bone window provided excellent bone detail, however, the soft tissue components of the TMJ were not as well visualised using a soft tissue window. The articular cartilage was observed as a hyperattenuating stripe over the low attenuated subchondral bone and good delineation was obtained between cortex and medulla. The tympanic and petrous part of the temporal bone (middle and inner ear) and the temporohyoid joint were seen in close proximity to the TMJ. Conclusions: Helical CT provided excellent images of the TMJ bone components to characterise the CT anatomy of the normal joint. Potential relevance: Detailed information is provided that may be used as a reference by equine veterinarians for the CT investigation of the equine TMJ and serve to assist them in the diagnosis of disorders of the TMJ and related structures (middle and inner ear). The study was performed at an immature stage and further studies of mature individuals are required in order to confirm that the clinical interpretation is not affected by changes occurring with age.  相似文献   
987.
It has been revealed that the 70-year-long application of fertilizers to a sugar beet crop rotation in the forest-steppe of the Central Chernozemic Zone has significantly affected the nitrogen status of leached chernozem and increased the content of mineral nitrogen and the mobility of nitrogen compounds. High application rates of mineral fertilizers create a positive nitrogen balance in the crop rotation and could minimize the losses of total nitrogen in the future.  相似文献   
988.
989.
Zusammenfassung Das Holz mehrerer gesunder, kr?nkelnder, absterbender oder bereits abgestorbener Tannen aus 3 in st?rkeren Ma? vom Tannensterben betroffenen bayerischen Wuchsgebieten war teils unmittelbar nach der F?llung, teils nach 3- bis 6-monatiger Lagerung im Wald auf Pilzbefall und m?glicherweise eingetretene Wertminderungen untersucht worden. Mit Ausnahme eines schon vor l?ngerer Zeit abgestorbenen Stammes waren alle H?lzer bei Versuchsbeginn noch frei von Mikroorganismen oder lediglich von Bakterien besiedelt. Nach einer gewissen Lagerzeit hatte neben dem Bl?uepilzCeratocystis piceae und einigen anderen harmlosen holzbewohnenden Ascomyceten oderFungi imperfecti gelegentlich auch der intensiv verf?rbende, das Tannenholz aber nur langsam abbauende Wei?f?uleerregerStereum chailletii die Probeabschnitte befallen. Zwischen dem Holz gesunder und gesch?digter Tannen war weder zum Zeitpunkt der F?llung noch sp?ter ein deutlicher qualitativer Unterschied erkennbar und die Holzdichte bzw.-festigkeitseigenschaften wurden durch eine Waldlagerung von maximal 6 Monaten nicht nennenswert beeintr?chtigt. Auch für die Anf?lligkeit gegenüber holzzerst?renden Pilzen war der Gesundheitszustand der untersuchten Tannen ohne Bedeutung.
Effects of the fir dieback on the wood properties of the affected trees
Summary Several healthy, diseased, dying, or already dead silver firs from each of three Bavarian growth areas considerably afflicted by fir dying were examined, regarding fungal attack and possible changes in their strength properties, immediately after felling as well as after 3 or 6 months of forest storage. At the onset of the investigation all wood samples were still largely free of microorganisms or merely colonized by bacteria, with the exception of one tree that had already died some time ago. After a certain storage period occasionally the white rot fungusStereum chailletii, which strongly discoloures and slowly decomposes fir wood, appeared besides the blue staining fungusCeratocystis piceae and several other harmless wood inhabiting ascomycetes orfungi imperfecti. Wood density and strength properties were not significantly affected during forest storage for several months, and neither immediately after felling nor later a clear difference between the wood of healthy and that of diseased firs was noticeable. Their state of health also had no influence on their reaction towards the attack of wood destroying fungi.
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990.
    
The components of grain yield are altered by adverse growing conditions as the effects of certain environmental factors on crop growth and yield differ depending upon the developmental stages when these conditions occur. Path-coefficient analysis was used to investigate the main processes influencing grain yield and its formation under Mediterranean conditions. Twenty-five durum wheat genotypes, consisting of four Spanish commercial varieties and 21 inbred lines from the ICARDA durum wheat breeding program, were grown during 1997 and 1998 under both rainfed and irrigated conditions in southern Spain. {P}ath-coefficient analysis revealed that under favourable conditions grain yield depended in equal proportion on the three primary yield components (i.e. spikes m−2, grains spike−1, and mean grain weight), whereas in the rainfed experiments, variations in grain yield were due mainly to spikes m−2 and to a lesser extent to grains spike−1. Compensatory effects were almost absent under irrigated treatments; however, under water shortage, spikes m−2 exerted a negative influence on grain spike−1 due mainly to a negative interrelationship between tiller production and apical development. These compensatory effects could partially explain the restricted success in durum wheat breeding observed in water-limited environments of the Mediterranean region. Under rainfed conditions the number of spikes m−2 depended mainly on the ability for tiller production, whereas in the irrigated experiments the final number of spikes was determined mostly by tiller survival.  相似文献   
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