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661.
Summary Third and fourth instar larvae and pupae of the facultatively myrmecophilous Palaearctic blue butterflyPolyommatus icarus showed no alteration in developmental time when reared in the presence of two species ofLasius ants. Sex differences were observed in larval growth and pupal weight, with males growing larger and faster. Sex-related
differences also occurred in the costs and benefits of ant-attendance. Male pupal masses tended to be larger in individuals
associated with ants, and their pupal weight loss was not enhanced by ant attendance. This positive developmental effect of
myrmecophily is tentatively attributed to a stimulating influence of ants on caterpillar feeding behavior. In contrast, females
associated with ants tended to lose more weight during the pupal stage. Hence there is evidence for developmental benefits,
rather than costs, of myrmecophily in maleP. icarus immatures, whereas ant attendance appears to be more costly for females during the pupal stage. These findings are discussed
in relation to data on other myrmecophilous lycaenid species. It is suggested that maintaining low-level myrmecophily and
its related organs is a comparatively inexpensive evolutionary stable strategy among this butterfly group. 相似文献
662.
S. Bojanowski A. Fiedler A. Frank E. A. Stadlbauer G. Schilling 《Engineering in Life Science》2007,7(6):593-598
Anaerobic low temperature conversion (LTC) converts organic residues such as animal meal or meat and bone meal (MBM) to bio‐crude, a solid product, containing carbon and phosphorus, reaction water and non‐condensable gases. The yield of bio‐crude increases with the content of volatile solids. The efficiency of the conversion as well as the calorific value of the liquid fuel produced are favorably affected by the partial recycling of inorganic constituents, high amounts of volatile solids and a low percentage of heteroatoms present in the feeding material. Heating values are 32.3 MJ/kg for bio‐crude from animal meal and 19.5 MJ/kg for bio‐crude from MBM. Both bio‐crude and animal fat produced were effectively converted in a vertical reactor construction with a fixed bed of aluminosilicates of the zeolite family or acidic clays, respectively. Products are bio‐fuels of varying chemical qualities. Depending on the reaction temperature and the catalyst type, aliphatic hydrocarbons (T = 400 °C, ~97 %) or alkylbenzenes (T = 550 °C) are the main products. The calorific values of these bio‐fuels are in a range from 40.1 to 41.9 MJ/kg and the kinematic viscosities are between 0.9 and 2.29 mm2/s. The solid products of LTC from different biomass (sludge, animal meal, MBM) contain a significant amount of phosphorus. In the case of the solid product from MBM it was as high as 242 mg P2O5/g. Solubility in citric acid showed that in the case of MBM, 98.8 % of total phosphorus is potentially available to plants. Pot experiments demonstrated a similar plant growth as with other organic fertilizers. 相似文献
663.
In the first phase after on oral glucose load or after sham-feeding of glucose in conscious intact or on the oesophagus fistulated dogs respectively, the peripheral venous plasma insulin concentration increases independently of any blood glucose alteration. After previous intravenous atropin injection, this reflectoric insulin secretion cannot be observed. The N. vagus is involved in the afferent and/or efferent side of the reinforcing mechanism of insulin secretion basing on the entero-insular axis. Additionally the enteral glucose absorption is inhibited. 相似文献
664.
L. Brüggemann S. Sommer E. Fiedler. K. Karbaum C. Albrecht R. Hedlich B. Nagel 《Engineering in Life Science》1990,10(1):79-84
The aim of the project BD1 (Biotechnology Data Bank 1) is to improve the data processing for research in biotechnology. In BD1, data of several classes of objects and methods are compiled. A data file conception consisting of object data files, method data files and feature data files was created, which can be easily extended to further classes, and which allows the combination of different classes of features to the same class of objects. There are two main approaches to use BD1: 1. making available informations on certain biotechnological objects, 2. the identification of unknown objects by means of their feature pattern. The microbiological data base and the possibilities of data base search are presented by example of lactic acid bacteria. 相似文献