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991.
992.
Karin Nuernberg Jaroslav Slamecka Jozef Mojto Jozef Gasparik Gerd Nuernberg 《European Journal of Wildlife Research》2011,57(4):795-803
The aim of this investigation was to characterise the fatty acid composition within intramuscular fat (IMF) of two muscles
(breast and thigh) from 28 pheasants, ten wild ducks and 27 black coots from Slovakia. A high variability for all single fatty
acids (FA) and the total fat concentration in muscles of wild birds was identified. Black coots deposited the highest fat
in breast muscle whereas wild ducks and pheasants accumulated more lipids in thigh muscle. In general, the content of polyunsaturated
fatty acids (PUFA) of the IMF in wild bird muscles was high, and the saturated FA concentration was lower compared with muscles
of domestic farm animals. The ratio between PUFA and saturated fatty acids (PSQ) ranked between 0.6 and 1.2, and the ratio
of n-6/n-3 fatty acid was favourably low in black coot and wild pheasants (3.2 and 2.9, respectively). Farmed pheasants had increased
IMF and more saturated and n-6 fatty acids deposited in thigh muscle but not in breast muscle. 相似文献
993.
Joel D. A. Tyndall Peter Timms Kenneth W. Beagley John A. Allan Charles W. Armitage Lynne Turnbull Cynthia B. Whitchurch Melisa Merdanovic Michael Ehrmann James C. Powers Jozef Oleksyszyn Martijn Verdoes Matthew Bogyo Wilhelmina M. Huston 《Molecular microbiology》2013,89(4):676-689
The mechanistic details of the pathogenesis of Chlamydia, an obligate intracellular pathogen of global importance, have eluded scientists due to the scarcity of traditional molecular genetic tools to investigate this organism. Here we report a chemical biology strategy that has uncovered the first essential protease for this organism. Identification and application of a unique CtHtrA inhibitor (JO146) to cultures of Chlamydia resulted in a complete loss of viable elementary body formation. JO146 treatment during the replicative phase of development resulted in a loss of Chlamydia cell morphology, diminishing inclusion size, and ultimate loss of inclusions from the host cells. This completely prevented the formation of viable Chlamydia elementary bodies. In addition to its effect on the human Chlamydia trachomatis strain, JO146 inhibited the viability of the mouse strain, Chlamydia muridarum, both in vitro and in vivo. Thus, we report a chemical biology approach to establish an essential role for Chlamydia CtHtrA. The function of CtHtrA for Chlamydia appears to be essential for maintenance of cell morphology during replicative the phase and these findings provide proof of concept that proteases can be targeted for antimicrobial therapy for intracellular pathogens. 相似文献
994.
Jia Sheng Jianhua Gan Alexei S. Soares Jozef Salon Zhen Huang 《Nucleic acids research》2013,41(22):10476-10487
Unlike DNA, in addition to the 2′-OH group, uracil nucleobase and its modifications play essential roles in structure and function diversities of non-coding RNAs. Non-canonical U•U base pair is ubiquitous in non-coding RNAs, which are highly diversified. However, it is not completely clear how uracil plays the diversifing roles. To investigate and compare the uracil in U-A and U•U base pairs, we have decided to probe them with a selenium atom by synthesizing the novel 4-Se-uridine (SeU) phosphoramidite and Se-nucleobase-modified RNAs (SeU-RNAs), where the exo-4-oxygen of uracil is replaced by selenium. Our crystal structure studies of U-A and U•U pairs reveal that the native and Se-derivatized structures are virtually identical, and both U-A and U•U pairs can accommodate large Se atoms. Our thermostability and crystal structure studies indicate that the weakened H-bonding in U-A pair may be compensated by the base stacking, and that the stacking of the trans-Hoogsteen U•U pairs may stabilize RNA duplex and its junction. Our result confirms that the hydrogen bond (O4…H-C5) of the Hoogsteen pair is weak. Using the Se atom probe, our Se-functionalization studies reveal more insights into the U•U interaction and U-participation in structure and function diversification of nucleic acids. 相似文献
995.
996.
Dana Cholujova Jana Jakubikova Branislav Czako Michaela Martisova Luba Hunakova Jozef Duraj Martin Mistrik Jan Sedlak 《Cancer immunology, immunotherapy : CII》2013,62(3):437-445
Dendritic cells (DCs) and natural killer (NK) cells are central components of innate immunity for controlling tumor growth. The therapeutic effects of certain anti-myeloma drugs are partially mediated by targeting the innate immune response. In addition, novel types of natural compounds have been developed that efficiently modulate the activity of both the cellular and humoral compartments of immunity. MGN-3 is known as an activator of natural killer cells, inducer of apoptosis and cytokine production, and modulator of dendritic cell maturation and differentiation in vitro. We have performed a randomized, placebo-controlled study to examine the effects of MGN-3 on innate immune system parameters in 48 multiple myeloma patients. We performed immunophenotypic analysis of peripheral blood samples, determined NK cell activity, and assessed the cytokine profiles of plasma before and during 3 months of treatment. The results demonstrate a clear increase in NK activity in MGN-3-treated patients compared to the placebo group, an increased level of myeloid DCs in peripheral blood, and augmented concentrations of T helper cell type 1-related cytokines. The present study suggests that MGN-3 may represent an immunologically relevant product for activating innate immunity in multiple myeloma patients and warrants further testing to demonstrate clinical efficacy. 相似文献
997.
Juraj Galko Bjørn Økland Troy Kimoto Slavomír Rell Milan Zúbrik Andrej Kunca Jozef Vakula Andrej Gubka Christo Nikolov 《Biologia》2018,73(4):361-370
A warmer climate may potentially have a strong effect on the health status of European oak forests by weakening oak trees and facilitating mass reproduction of wood boring insects. We did a laboratory experiment in Slovakia to study the response of major pest beetles of oak and their parasitoids to different temperature regimes as background for predicting climatic effects and improving management tools of European oak forests. With higher temperatures the most important oak pest Scolytus intricatus emerged much earlier, which indicate that completion of a second generation and increased damage further north in European oak forests may be possible. Lower temperatures gave longer larval galleries and more offspring per parents but still lower beetle production due to semivoltine life cycle. For buprestids and longhorn beetles warmer temperatures resulted in more emerging offspring and a shift towards earlier emergence in the same season, but no emergence in the first season indicated that a change to univoltine populations is not likely. Reduced development success of parasitoids at the highest temperatures (25/30 °C) indicates a loss of population regulation for pest beetle populations. A warmer climate may lead to invasion of other population-regulating parasitoids, but also new serious pest may invade. With expected temperature increases it is recommended to use trap trees both in April and in June, and trap trees should be removed within 2 months instead 1 year as described in the current standard. 相似文献
998.
Jana Teleky Oleg Melnik Teodor Tóth Dušan Rajský Jozef Kremeň Eva Petrovová Slávka Flešárova 《Biologia》2018,73(4):379-387
Like in most European countries, the population of the European beaver (Castor fiber) in Slovakia became extinct in the nineteenth century. Thanks to reintroduction of beavers in neighboring states, after a long break the beaver returns also to the territory of Slovakia. This has particularly affected the present distribution of beavers in the Slovak Republic. The first aim of the work was to find phylogenetic similarities of the northeastern Slovak population with the Ukrainian and Polish ones comparing their adult skulls and mandibles on the basis of craniometric measurements. A total of 28 measurements were taken on each skull and mandible. The statistical evaluation showed that the most similar were the Slovak and Ukrainian skulls, while in 8 cranial parameters the Ukrainian and Polish populations were found to be significantly different. The second aim was related to their ability to fell trees. The enamel thickness of incisors in the jaw and mandible were compared within the Slovak sample by measuring for 18 teeth, which were previously scanned by the X-Ray Computer Tomography. The results showed that the average thickness of incisors enamel in the mandible was 0.34 mm, while the incisors of the maxilla had enamel approximately 0.29 mm thick. 相似文献
999.
Fourteen West Tatra lakes were studied, of which one could be considered to be recently anthropogenically acidified and eight
others classified as acidification-endangered. In the anthropogenically acidified lake, the zooplankton assemblage has been
substantially altered (three mountain-lake crustacean species have been eliminated). Several littoral macrobenthic species
sensitive to acidification have either been eliminated from the acidified and acidification-endangered lakes or occur only
sporadically. The effect of acidification has so far not been observed on the benthic fauna of the lakes medial which is probably
due to the higher pH below the surface of sediment. In comparison with the High Tatra, acid depositions have had a less pronounced
effect on the lakes of the West Tatra. 相似文献
1000.
G. E. Hollway Graeme K. Suthers Eric A. Haan Elizabeth Thompson David J. David Jozef Gecz John C. Mulley 《Human genetics》1997,99(2):251-255
Five autosomal dominant craniosynostosis syndromes (Apert, Crouzon, Pfeiffer, Jackson-Weiss and Crouzon syndrome with acanthosis
nigricans) result from mutations in FGFR genes. Fourteen unrelated patients with FGFR2-related craniosynostosis syndromes were screened for mutations in exons IIIa and IIIc of FGFR2. Eight of the nine mutations found have been reported, but one patient with Pfeiffer syndrome was found to have a novel G-to-C
splice site mutation at –1 relative to the start of exon IIIc. Of those mutations previously reported, the mutation C1205G
was unusual in that it was found in two related patients, one with clinical features of Pfeiffer syndrome and the other having
mild Crouzon syndrome. This degree of phenotypic variability shows that the clinical features associated with a specific mutation
do not necessarily breed true.
Received: 4 June 1996 / Revised: 3 September 1996 相似文献