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81.
J. J. Bautista‐Romero S. S. González‐Peláez L. Campos‐Dávila D. B. Lluch‐Cota 《Zeitschrift fur angewandte Ichthyologie》2012,28(2):269-271
Length–weight relationships (LWR) were estimated for 34 fish species belonging to 25 genera and 17 families, specimens were collected near the mouth of the Río Verde, Oaxaca, Mexico. All r2 values are statistically significant (P > 0.0001). The values of ‘b’ ranged from 2.55 and 3.3, within the usual range (2.5–3.5). This study provides the first LWR references for six species, and new maximum length records for eight species. 相似文献
82.
The glutamine synthetase (EC 6.3.1.2) from the haloarchaeon Haloferax mediterranei has been purified and characterized in order to understand the ammonium assimilation in haloarchaea. Based on sodium dodecyl sulfate polyacrylamide gel electrophoresis and gel-filtration chromatography, the enzyme consists of eight subunits of 51.7 kDa, suggesting that this enzyme belongs to the glutamine synthetase type II. The purified enzyme has been characterized with respect to its optimum temperature (45 degrees C) and pH value (8.0). The optimal NaCl or KCl concentrations for the reaction were 0.5 and 0.25 M, respectively. The effect of l-methionine-d, l-sulphoximine and different divalent metal ions has also been tested. The glutamine synthetase presented here is unusual; it shows the typical characteristic of eukaryotic and soil bacteria glutamine synthetases. 相似文献
83.
84.
A new species of Acritopappus, A. buiquensis, is described and illustrated from Pernambuco State, Brazil. This is the second record for the genus in the State. The position
of A. buiquensis in the genus is discussed. 相似文献
85.
F. Pérez-Pomares S. Díaz V. Bautista C. Pire G. Bravo J. Esclapez B. Zafrilla María-José Bonete 《Extremophiles : life under extreme conditions》2009,13(4):633-641
Three different amylolytic activities, designated AMY1, AMY2, and AMY3 were detected in the cytoplasm of the extreme halophilic
archaeon Haloferax mediterranei grown in a starch containing medium. This organism had also been reported to excrete an α-amylase into the external medium
in such conditions. The presence of these different enzymes which are also able to degrade starch may be related to the use
of the available carbohydrates and maltodextrins, including the products obtained by the action of the extracellular amylase
on starch that may be transported to the cytoplasm of the organism. The behavior of these intracellular hydrolytic enzymes
on starch is reported here and compared with their extracellular counterpart. Two of these glycosidic activities (AMY1, AMY3)
have also been purified and further characterized. As with other halophilic enzymes, they were salt dependent and displayed
maximal activity at 3 M NaCl, and 50°C. The purification steps and molecular masses have also been reported. The other activity
(AMY2) was also detected in extracts from cells grown in media with glycerol instead of starch and in a yeast extract medium.
This enzyme was able to degrade starch yielding small oligosaccharides and displayed similar halophilic behavior with salt
requirement in the range 1.5–3 M NaCl.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
86.
Ernest J. Harris Renato C. Bautista Roger I. Vargas Eric B. Jang Avraham Eitam Luc Leblanc 《BioControl》2010,55(5):593-599
Field experiments and surveys were conducted to evaluate the efficacy of releasing Fopius arisanus (Sonan) and Psyttalia fletcheri (Silvestri) parasitoids for suppression of Bactrocera cucurbitae (Coquillett) infesting wild Coccinia grandis L. In 2003 and 2004, P. fletcheri releases combined with natural emergence from wild fly populations resulted in better fly suppression, compared to the control site. While P. fletcheri developed freely on melon fly, F. arisanus was less successful at producing its own progeny, yet causing mortality and a twofold decrease in pupae recovered from ivy gourds. Concurrent releases of both parasitoids exerted a compounded suppressive effect on the melon fly population 2–3 times higher than during the pre-release phase. A similar, less obvious, pattern occurred in 2004, due to reduction of the ivy gourd fruit canopy. In 2005, only P. fletcheri was released, with greatly reduced impact, due to ivy gourd destruction and by growers leaving crop culls in fields, producing large numbers of melon flies unaffected by parasitoid releases. 相似文献
87.
Background
Nepal is small in size but rich in bio-cultural diversity. The rugged terrain of the country is home to a number of unique assemblages of fauna, some of which are endemic. Not only faunal resources the country also harbors some very ancient populations whose interrelationship with these diverse faunal resources is very intimate and thus demands scientific study. Animals play important role in both material and spiritual spheres of their life. There are more than hundred groups of such populations in the country and the group Tamang is one of these. The present paper studies Tamang-animal relationships in central Nepal. There is a growing trend of scientific ethnozoological studies all across the globe, but this field is yet in its infancy in Nepal. The country is losing important fauna as well as ancient human cultures at the advent of development processes. As a result, ethnozoological knowledge is also teetering on the brink of extinction.Methods
Ethnozoological data were collected by applying different participatory approaches techniques such as semi-structured interviews, participatory rural appraisal, key informant interviews and focus group discussions. Quantitative data were obtained by employing a household level questionnaire survey. Data were collected from the period of September 2004 to August 2005. Most of the animals were identified up to the species level with the help of standard taxonomic keys.Results
The Tamang community treasures knowledge on various uses of 41 genera belonging to 28 families. Out of total number of animals, 14.6% belong to the Invertebrate group and the rest to the Vertebrate group. Of the total uses 58% fall in the food and medicinal use category, 16% in the magico-religious use category, 18% in the category of omen indication, and 2% each in the categories such as weather forecasting, trophy, ethnomusical and taboos.Conclusions
The Tamang maintain strong ties with animals both at a material as well as spiritual level. While some animals are the sources of important traditional medicines, others are omen indicators and weather forecasters. High priority should be given in conservation of those animals which are of high consensus value to the community. 相似文献88.
Using a conditioning paradigm, the olfactory sensitivity of four spider monkeys and four pigtail macaques for a homologous series of carboxylic acids (n-propionic acid to n-heptanoic acid) was investigated. With only few exceptions, the animals of both species significantly discriminated concentrations <1 p.p.m. from the odorless solvent and in several cases individual monkeys even demonstrated thresholds <1 p.p.b. The results showed (i). both primate species to have a well-developed olfactory sensitivity for carboxylic acids, which for some substances matches or even is markedly better than that of species such as the rat or the dog and (ii). a significant correlation between perceptibility in terms of olfactory detection thresholds and carbon chain length of the carboxylic acids in both species tested. These findings lend further support to the growing body of evidence suggesting that between-species comparisons of the number of functional olfactory receptor genes or of neuroanatomical features are poor predictors of olfactory performance, and that general labels such as 'microsmat' or 'macrosmat'-which usually are based on allometric comparisons of olfactory brain structures-are inadequate to describe a species' olfactory capabilities. 相似文献
89.
90.
Bautista James A. Chynwat Veeradej Cua Agnes Jansen Frans Jos Lugtenburg Johan Gosztola David Wasielewski Michael R. Frank Harry A. 《Photosynthesis research》1998,55(1):49-65
The spectroscopic and photochemical properties of the synthetic carotenoid, locked-15,15-cis-spheroidene, were studied by absorption, fluorescence, circular dichroism, fast transient absorption and electron spin resonance spectroscopies in solution and after incorporation into the reaction center of Rhodobacter (Rb.) sphaeroides R-26.1. HPLC purification of the synthetic molecule reveals the presence of several di-cis geometric isomers in addition to the mono-cis isomer of locked-15,15-cis-spheroidene. In solution, the absorption spectrum of the purified mono-cis sample was red-shifted and showed a large cis-peak at 351 nm compared to unlocked all-trans spheroidene. Molecular modeling and semi-empirical calculations reveal how geometric isomerization and structural factors affect the room temperature spectra. The spectroscopic studies of the purified locked-15,15-mono-cis molecule in solution reveal a more stable manifold of excited states compared to the unlocked spheroidene. Reaction centers of Rb. sphaeroides R-26.1 in which the locked-15,15-cis-spheroidene was incorporated show no difference in either the spectroscopic properties or photochemistry compared to reaction centers in which unlocked spheroidene was incorporated or to Rb. sphaeroides wild type strain 2.4.1 reaction centers which naturally contain spheroidene. The data suggest that the natural selection of a cis-isomer of spheroidene for incorporation into native reaction centers of Rb. sphaeroides wild type strain 2.4.1 is more determined by the structure or assembly of the reaction center protein than by any special quality of the cis-isomer of the carotenoid that would affect its ability to participate in triplet energy transfer or carry out photoprotection. 相似文献