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91.
92.
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
93.
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
94.
95.
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
96.
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
97.
Patr��cia F N Fa��sca Ana Nunes Rui DM Travasso Eugene I Shakhnovich 《Protein science : a publication of the Protein Society》2010,19(11):2196-2209
Systematic Monte Carlo simulations of simple lattice models show that the final stage of protein folding is an ordered process where native contacts get locked (i.e., the residues come into contact and remain in contact for the duration of the folding process) in a well‐defined order. The detailed study of the folding dynamics of protein‐like sequences designed as to exhibit different contact energy distributions, as well as different degrees of sequence optimization (i.e., participation of non‐native interactions in the folding process), reveals significant differences in the corresponding locking scenarios—the collection of native contacts and their average locking times, which are largely ascribable to the dynamics of non‐native contacts. Furthermore, strong evidence for a positive role played by non‐native contacts at an early folding stage was also found. Interestingly, for topologically simple target structures, a positive interplay between native and non‐native contacts is observed also toward the end of the folding process, suggesting that non‐native contacts may indeed affect the overall folding process. For target models exhibiting clear two‐state kinetics, the relation between the nucleation mechanism of folding and the locking scenario is investigated. Our results suggest that the stabilization of the folding transition state can be achieved through the establishment of a very small network of native contacts that are the first to lock during the folding process. 相似文献
98.
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
99.
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100.