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排序方式: 共有243条查询结果,搜索用时 156 毫秒
91.
Portes KF Ikegami CM Getz J Martins AP de Noronha L Zischler LF Klassen G Camargo AA Zanata SM Bevilacqua E Nakao LS 《Journal of molecular histology》2008,39(2):217-225
Quiescin Q6/sulfhydryl oxidases (QSOX) are revisited thiol oxidases considered to be involved in the oxidative protein folding,
cell cycle control and extracellular matrix remodeling. They contain thioredoxin domains and introduce disulfide bonds into
proteins and peptides, with the concomitant hydrogen peroxide formation, likely altering the redox environment. Since it is
known that several developmental processes are regulated by the redox state, here we assessed if QSOX could have a role during
mouse fetal development. For this purpose, an anti-recombinant mouse QSOX antibody was produced and characterized. In E13.5, E16.5 fetal tissues, QSOX immunostaining was confined to mesoderm- and ectoderm-derived tissues, while in P1 neonatal tissues it
was slightly extended to some endoderm-derived tissues. QSOX expression, particularly by epithelial tissues, seemed to be
developmentally-regulated, increasing with tissue maturation. QSOX was observed in loose connective tissues in all stages
analyzed, intra and possibly extracellularly, in agreement with its putative role in oxidative folding and extracellular matrix
remodeling. In conclusion, QSOX is expressed in several tissues during mouse development, but preferentially in those derived
from mesoderm and ectoderm, suggesting it could be of relevance during developmental processes.
Kelly F. Portes, Cecília M. Ikegami have contributed equally to this work. 相似文献
92.
The global threat of terrorism raises questions about preparedness and risk communication in the context of public health and security. Although experts discriminate between chemical, biological, radiological, nuclear, and explosive (CNRNE) terrorist events, little is known about how the Canadian public represents these forms of terrorism. A stratified random sample of 1502 Canadians participated in a telephone survey on CBRNE terrorism. A word association technique was used to assess first words or images that came to mind while thinking about different types of terrorist scenarios. Content analysis of this data revealed a number of potential uncertainties and misconceptions regarding different types of terrorism scenarios. Despite most frequently providing agents in response questions surrounding chemical or biological terrorism, respondents frequently confounded agents of biological and chemical nature. Similarly, different aspects of nuclear events were not consistently distinguished. Most notably, however, a sizable proportion of respondents had difficulty providing word associations to the different types of terrorist events or only provided vague responses that closely mirrored the scenario in question. Finally, images regarding the potential impacts of scenarios were infrequent. Implications for risk communication and preparedness are discussed; in particular, the need to provide the public with more detailed information regarding the nature of different forms of CBRNE terrorism and how to best prepare for a potential event. 相似文献
93.
Joel G Ray Loralie J Langman Marian J Vermeulen Jovan Evrovski Erik L Yeo David EC Cole 《Trials》2001,2(3):141-9
Background
Women may be at increased risk for venous thromboembolism (VTE) as compared with men. We studied the effects of genetic and biochemical markers of thrombophilia in women, in conjunction with other established risk factors for VTE. 相似文献94.
The agricultural sector, and particularly the horticultural production, has a singular importance in agriculture, considering that it ranks second on agricultural products, nationally and worldwide. Fungal diseases are one of the major causes of vegetable loss during storage, reducing their nutritional value, quality and sale price. Vegetables are usually exposed to diverse treatments with chemical products before storage; as a result, fungal populations develop an increased resistance over time becoming more difficult to control. Because of this, research efforts toward finding more suitable chemicals to control fungal diseases are needed. Natural extracts may be an alternative solve this problem. In the present investigation the fungicidal activity of aqueous and ethanol extracts of Agave scabra was evaluated on the growth of Botrytis cinerea, Mucor sp., Aspergillus niger, Fusarium sp. and Penicillium sp., whose strains were isolated from potato and tomato. To assess their effects, the agar-dilution and agar-well techniques were performed. The ethanol extract was more effective against Botrytis cinerea and Mucor sp. when the agar-well method was used. However, when using the agar-dilution method the ethanol extract of Agave scabra inhibited the growth of Botrytis cinerea, Mucor sp. and Penicillium sp. 相似文献
95.
96.
New Zealand rabbits were infected on day 1 and challenged on days 15, 30, and 60 with 1,000 Schistosoma mansoni cercariae/animal/infection. Challenged and control rabbits were perfused 60 days after each infection, corresponding to days 75, 90, and 120 after the first exposure. No decrease in number of adult schistosomes occurred in animals reinfected 15 days after primary infection, but, when the rabbits were challenged 30 and 60 days after the first infection, worm burden reduction of 61.4% and 92.6%, respectively, was observed as compared to infection controls. These data indicate that rabbits submitted to reinfection are able to kill the worms from their primary infection, besides being protected against challenge parasites. 相似文献
97.
S M Jethmalani G Viswanathan C Bandyopadhyay J M Noronha 《Indian journal of experimental biology》1989,27(12):1052-1055
Acute (after 4 hr) and short-term (after 7 days) effects of ingesting heated and unheated groundnut, coconut and safflower oils on plasma lipids, lipoproteins and postheparin lipopolytic activity (PHLA) were studied in rats. All heated oils were characterized by increases in carbonyl value, peroxide value and free fatty acid (FFA) content, except heated coconut oil which showed a decrease in FFA content. Heating procedure also did not alter to an appreciable extent their fatty acid compositions. Acute and short-term effects of feeding heated and unheated oils showed no significant differences in rat plasma levels of total cholesterol (TC), total triglycerides, total phospholipids, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol + very-low-density lipoprotein cholesterol, TC/HDL-C ratio and PHLA. Inspite of certain changes in some of the indices of thermal alteration of these heated oils, consumption of such heated oils by rats did not have any significant effect on various plasma parameters in these animals. 相似文献
98.
Ribonucleotide reductase has been shown to be associated with the DNA-membrane complex in Escherichia coli TAU- cells. The membrane-bound enzyme has been released in a soluble form using a combined treatment of 1% sarcosyl (pH 8.0) and 1% sodium deoxycholate (pH 6.5). Allotropic differences in the modulatory effects of ATP, Mg2+, EDTA and dithiothreitol on the membrane-bound and solubilized enzyme activity are discussed. 相似文献
99.
Positive selection and sequence rearrangements generate extensive polymorphism in the gamete recognition protein bindin 总被引:27,自引:12,他引:15
Bindin is a gamete recognition protein of sea urchins that mediates
species-specific attachment of sperm to an egg-surface receptor during
fertilization. Sequences of bindin from closely related urchins show fixed
species-specific differences. Within species, highly polymorphic bindin
alleles result from point substitution, insertion/deletion, and
recombination. Since speciation, positive selection favoring allelic
variants has generated diversity in bindin polypeptides. Intraspecific
bindin variation can be tolerated by the egg receptor, which suggests
functional parallels between this system and other flexible recognition
systems, including immune recognition. These results show that polymorphism
in mate recognition loci required for rapid evolution of sexual isolation
can arise within natural populations.
相似文献
100.
The molecular evolution of the alcohol dehydrogenase and alcohol dehydrogenase-related genes in the Drosophila melanogaster species subgroup 总被引:5,自引:0,他引:5
The DNA sequences of the Adh genes of three members of the Drosophila
melanogaster species subgroup have been determined. This completes the Adh
sequences of the eight species of this subgroup. Two species, D. yakuba and
D. teissieri, possess processed Adh pseudogenes. In all of the species of
the subgroup, a gene of unknown function, Adhr, is located about 300 bp 3'
to Adh. Although this gene is experiencing a higher rate of synonymous
substitution than Adh, it is more constrained at the amino acid level.
Phylogenetic relationships between all eight members of the melanogaster
subgroup have been analyzed using a variety of methods. All analyses
suggested that the D. yakuba and D. teissieri pseudogenes have a single
common ancestor, rather than evolving independently in each species, and
that D. melanogaster is the sister species to D. simulans, D. sechellia,
and D. mauritiana. The evolutionary relationships of the latter three
species remain equivocal.
相似文献