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71.
72.
Matthew K. Egbekun John I. Akowe Ruth J. Ede 《Plant foods for human nutrition (Dordrecht, Netherlands)》1996,49(4):301-306
The fresh ripe fruit pulp and syrup, produced using the open pan evaporator, ofVitex doniana were analysed physico-chemically. Results show that the edible pulp of the ripe fruit is fairly rich in vitamin C (18.1 mg/100 ml) but acidic (pH 4.38) and poor in protein (0.82%) and oil (0.56%). The syrup yielded a DE value of 52, total dissolved solids content of 67° Brix and a refractive index of 1.4762 at 20°C. The syrup was moderately visous (2.1 Poiseuille), acid (pH 4.45) but relatively poor in vitamin C (2.8 mg/100 ml) and protein (0.3%). Sensory evaluation showed no significant difference (p0.05) in taste, flavor and overall acceptability betweenV. doniana syrup and honey. Both physico-chemical and sensory results indicate that the syrup was highly desirable and can substitute for other syrups as a nutritive sweetener. 相似文献
73.
The aim of this study was to first evaluate whether the chitosan hydrochloride-genipin crosslinking reaction is influenced by factors such as time, and polymer/genipin concentration, and second, to develop crosslinked drug loaded microspheres to improve the control over drug release. Once the crosslinking process was characterized as a function of the factors mentioned above, drug loaded hydrochloride chitosan microspheres with different degrees of crosslinking were obtained. Microspheres were characterized in terms of size, morphology, drug content, surface charge and capacity to control in vitro drug release. Clarithromycin, tramadol hydrochloride, and low molecular weight heparin (LMWH) were used as model drugs. The obtained particles were spherical, positively charged, with a diameter of 1–10 μm. X-Ray diffraction showed that there was an interaction of genipin and each drug with chitosan in the microspheres. In relation to the release profiles, a higher degree of crosslinking led to more control of drug release in the case of clarithromycin and tramadol. For these drugs, optimal release profiles were obtained for microspheres crosslinked with 1 mM genipin at 50 ºC for 5 h and with 5 mM genipin at 50 ºC for 5 h, respectively. In LMWH microspheres, the best release profile corresponded to 0.5 mM genipin, 50 ºC, 5 h. In conclusion, genipin showed to be eligible as a chemical-crosslinking agent delaying the outflow of drugs from the microspheres. However, more studies in vitro and in vivo must be carried out to determine adequate crosslinking conditions for different drugs. 相似文献
74.
75.
Die Wassererosion, initiiert durch anthropogene Eingriffe durch Bodennutzung, führte zu veränderten Bodenprozessen und einer starken Bodenprofilverkürzung an konvexen und einer Sedimentakkumulation an konkaven Hangbereichen. Die Abtragsbilanz kann durch eine Bodenneubildung nicht annähernd ausgeglichen werden. Der Grad der Veränderung kann durch den Vergleich mit Waldböden der gleichen Genese und Morphologie im Landschaftsausschnitt bestimmt werden, da diese kaum eine Differenzierung zwischen konvexen und konkaven Hangbereichen aufweisen. Der Veränderungsgrad kann durch die Korngrößenzusammensetzung, die Entkalkungstiefe sowie den Gehalt an organischer Bodensubstanz eingeschätzt werden. Die Gehalte an Corg zeigen den Grad der erosionsbedingten Bodendegradierung sehr deutlich. Die Zusammensetzung der leicht abbaubaren OBS differiert viel weniger und wird offenbar durch die aktuelle Nutzung überprägt. An einer weiteren Aufklärung der Veränderung der organischen Bodensubstanz an erosionsbeeinflussten Hängen wird geforscht, weil dieser Parameter als ein wichtiger Indikator für den Zustand und die Degradierung der Böden angesehen werden kann. 相似文献
76.
The course of events from taking a food into the mouth to the perception of the food's flavor involves many steps, from dilution with saliva, mastication, and transportation of the compounds to the olfactory epithelium to transformation into signals that go to the brain. In addition, there are also the effects of the food's structure and properties. In this study, a proton-transfer-reaction mass spectrometer (PTR-MS) was used to investigate how four pectin-containing systems with different structures and strengths affected the release of aroma compounds in a model mouth and in the nose of an assessor. Both the model mouth and the in-nose measurements showed that the strength and structure of pectin-containing systems are important with regard to the quantity of aroma compounds that are released. Mastication and saliva were also shown to have a large influence on how much of the aroma compound is released from the mouth to the nose. 相似文献
77.
Trajectory shifts in the Arctic and subarctic freshwater cycle 总被引:1,自引:0,他引:1
Peterson BJ McClelland J Curry R Holmes RM Walsh JE Aagaard K 《Science (New York, N.Y.)》2006,313(5790):1061-1066
Manifold changes in the freshwater cycle of high-latitude lands and oceans have been reported in the past few years. A synthesis of these changes in freshwater sources and in ocean freshwater storage illustrates the complementary and synoptic temporal pattern and magnitude of these changes over the past 50 years. Increasing river discharge anomalies and excess net precipitation on the ocean contributed approximately 20,000 cubic kilometers of fresh water to the Arctic and high-latitude North Atlantic oceans from lows in the 1960s to highs in the 1990s. Sea ice attrition provided another approximately 15,000 cubic kilometers, and glacial melt added approximately 2000 cubic kilometers. The sum of anomalous inputs from these freshwater sources matched the amount and rate at which fresh water accumulated in the North Atlantic during much of the period from 1965 through 1995. The changes in freshwater inputs and ocean storage occurred in conjunction with the amplifying North Atlantic Oscillation and rising air temperatures. Fresh water may now be accumulating in the Arctic Ocean and will likely be exported southward if and when the North Atlantic Oscillation enters into a new high phase. 相似文献
78.
Mercedes Fernandez-Moreno Alberto Arias-Perez Ruth Freire & Josefina Méndez 《Aquaculture Research》2008,39(5):474-481
Aequipecten opercularis (Queen scallop) and Mimachlamys (Chlamys) varia (Black scallop) are important natural resources occurring in Atlantic and Mediterranean coasts. To develop an optimal sustainable exploitation plan, it is important to study the genetic structure of the different populations. In this study, we used polymerase chain reaction‐restriction fragment length polymorphisms for the determination of the genetic variation and population structure of these two species in different localities. Ten composite haplotypes were generated for A. opercularis and 15 haplotypes for M. varia. Of these, six and four were unique respectively. The analysis of the distribution of the different haplotypes between the localities showed no clear evidence of subdivision in A. opercularis, while in M. varia the results indicated that the two localities analysed should be managed as separate stocks. 相似文献
79.
Jose M Carral Jesús D Celada Maria Sáez-Royuela Ruth Rodríguez Amelia Aguilera & Pedro Melendre 《Aquaculture Research》2006,37(6):632-636
Four desticking procedures for tench eggs (A: tannic acid solution (1 g L−1) for 15 s; B: alcalase enzyme solution (8 mL L−1) for 60 s; C: alcalase enzyme solution (15 mL L−1) for 120 s; D: Woynarovich and Woynarovich (1980) solution for 58 min followed by tannic acid solution (1 g L−1) for 15 s) were tested to obtain data about influence on embryo survival to hatching stage and further survival and growth of the larvae. In the tannic acid and Woynarovich and Woynarovich (1980) treatment (A and D) few eggs stuck together and some were adhered to the incubator walls, whereas in the alcalase treatments (B and C) eggs neither stuck together nor adhered to the incubator walls. Percentages of hatched larvae did not show significant differences (mean values ranged between 47.4% in treatment A to 37.0% in treatment C). Larvae deformities observed were <0.5% in all cases. There were no significant differences among survival and growth rates of the larvae from different egg desticking origin, reaching, after 30 days, mean survival values around 90% and total length and weight of 12.5 mm and 19 mg respectively. 相似文献
80.
Gordon H Copp J Robert Britton Julien Cucherousset Emili García‐Berthou Ruth Kirk Edmund Peeler Saulius Stakėnas 《Fish and Fisheries》2009,10(3):252-282
A popular species for food and sport, the European catfish (Silurus glanis) is well‐studied in its native range, but little studied in its introduced range. Silurus glanis is the largest‐bodied freshwater fish of Europe and is historically known to take a wide range of food items including human remains. As a result of its piscivorous diet, S. glanis is assumed to be an invasive fish species presenting a risk to native species and ecosystems. To assess the potential risks of S. glanis introductions, published and ‘grey’ literature on the species’ environmental biology (but not aquaculture) was extensively reviewed. Silurus glanis appears well adapted to, and sufficiently robust for, translocation and introduction outside its native range. A nest‐guarding species, S. glanis is long‐lived, rather sedentary and produces relatively fewer eggs per body mass than many fish species. It appears to establish relatively easily, although more so in warmer (i.e. Mediterranean) than in northern countries (e.g. Belgium, UK). Telemetry data suggest that dispersal is linked to flooding/spates and human translation of the species. Potential impacts in its introduced European range include disease transmission, hybridization (in Greece with native endemic Aristotle’s catfish [Silurus aristotelis]), predation on native species and possibly the modification of food web structure in some regions. However, S. glanis has also been reported (France, Spain, Turkmenistan) to prey intensively on other non‐native species and in its native Germany to be a poor biomanipulation tool for top‐down predation of zooplanktivorous fishes. As such, S. glanis is unlikely to exert trophic pressure on native fishes except in circumstances where other human impacts are already in force. In summary, virtually all aspects of the environmental biology of introduced S. glanis require further study to determine the potential risks of its introduction to novel environments. 相似文献