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141.
Brazil has one of the highest rates of scientific production, occupying the ninth position among countries with genome-sequencing projects. Considering the rapid development of this research area and the diversity of professionals involved, the present study aims to understand the expectations, past experiences and the current scenario of Brazilian research in bioinformatics and genomics. The present research was carried out by analyzing the perceptions of 576 researchers in genomics and bioinformatics in Brazil through content and sentiment analysis techniques. This group of participants is equivalent to 48% of the members of the research community. The results suggest that most researchers have a positive perception of the potential of this research area. However, there is concern about the lack of funding for investing in equipment and professional training. As part of a wish list for the future, researchers highlighted the need for higher funding, formal education, and collaboration among research networks. When asked about genomics and bioinformatics in other countries, the participants recognize that sequencing technologies and infrastructure are more accessible, allowing better data volume expansion.  相似文献   
142.
The aim was to investigate pathogen survival during composting of pig manure solids with and without bulking agents in two trials of 56 days duration, each with four treatments. Salmonella was detected in the sawdust and straw bulking agents but was undetectable in the compost, except in one treatment at day 0. Enteric indicator organisms were reduced by day 7 (P<0.001) and were undetectable in the final compost, except for coliform which were present at 3.66-4.43 log?? CFU/g. Yeasts and moulds were reduced and aerobic spore-formers remained stable in one trial but both increased in the other (P<0.001). Bacillus licheniformis and Clostridium sporogenes were the predominant culturable spore-forming bacteria recovered. Microbial counts were influenced by the bulking agent but only at particular time points (P<0.05). Overall, the pig manure-derived compost complied with EU regulations for processed manure products, as E. coli and Enterococcus were below limits and it was Salmonella-free.  相似文献   
143.
Terror, Edmund Burke argued, is the “common stock of everything that is sublime,” capable of producing delight when held at a certain distance. What puzzled Burke was the question of “how any species of delight can be derived from a cause so apparently contrary to it.” I suggest that we may look for an ethnographic answer to this question among the supporters, hangers-on and diverse admirers of outlaw bikers, who take pleasure in being exposed, albeit at a safe distance, to the sublime splendor of the biker’s power of intimidation. Grounded in ethnographic research among outlaw bikers in central Europe, analysis of popular visual culture and biker literature, this article argues that “sublime experience” is one of the indispensable ingredients of the aesthetics of power of the outlaw bikers.  相似文献   
144.
Diabetes mellitus (DM) is associated with a high risk of health complications, mainly due to excessive free radical (FRs) production that could result in an increased frequency of micronuclei. The consumption of antioxidants, like folic acid (FA), may mitigate the effects of the FRs. In the present study, micronucleated polychromatic erythrocyte (MNPCE) frequencies were determined in blood sampled weekly from the tails of pregnant female Wistar rats and pregnant Wistar rats with experimental diabetes that were given unsupplemented diets and diets supplemented with FA. At birth, the pups were sampled to analyze micronucleated erythrocyte (MNE) and MNPCE frequencies. Moreover micronucleated cells (MNCs) were evaluated in buccal mucosa samples taken from 81 healthy adult subjects, 48 patients with DM, and 30 DM patients who were sampled before and after FA treatment. Increases in MNPCE frequencies were significant only at the first sampling (P<0.01 and P<0.03) in pregnant rats with experimental diabetes. In addition, the pups from the diabetic group and from diabetic group treated with FA had higher frequencies of MNEs (P<0.03 and P<0.001, respectively) and MNPCEs (P<0.009 and P<0.05, respectively) than the controls. No differences were found in diabetic rats and newborn rats born to diabetic mothers treated with FA compared with untreated animals. Patients with DM had a higher frequency of MNCs compared with healthy subjects (P<0.001). Also FA reduced the frequency of MNCs in DM patients (P<0.001). The results of this study indicate that diabetes results in elevated frequencies of micronuclei, and that, at least in humans, FA can protect against the elevation.  相似文献   
145.
Thyroid hormone (T3) plays an important role in gene regulation in the liver. Previous studies have been done in complex systems such as animal models, or in transformed malignant hepatic cell lines in which thyroid hormone receptor (TR) was over-expressed by co-transfection. Therefore, the aim of this study was to characterize T3-responsive genes in a simple system, by using a non-transformed hepatic cell line that is able to express sufficient amounts of endogenous TRs. For this purpose we used the murine non-transformed hepatocyte cell line AML 12. We performed analyses using a cDNA microarray containing 15,000 murine genes. We found 12 genes to be up-regulated and 5 genes to be down-regulated in the presence of T3. For some of the genes not previously known to be regulated by T3, we confirmed the regulation by T3 using real-time PCR. Our data in AML 12 cells provide a simple and physiologically relevant system to study T3 action, without the influence of neoplastic transformation or artificial TR over-expression. Furthermore, our data describe novel T3 responsive genes and provide insight into the role of T3 in important processes such as cholesterol metabolism, bile acid secretion, oncogenesis, among others, that can be tested in future experiments in vivo.  相似文献   
146.
S-nitrosylation of protein cysteine thiol groups has recently emerged as a widespread and important reversible post-translational protein modification, involved in redox signalling pathways of nitric oxide and reactive nitrogen species. S-nitrosoglutathione reductase (GSNOR), member of class III alcohol dehydrogenase family (EC 1.1.1.1), is considered the key enzyme in the catabolism of major low molecular S-nitrosothiol, S-nitrosoglutathione, and hence to control the level of protein S-nitrosylation. Changes of GSNOR activity after exposure to different abiotic stress conditions, including low and high temperature, continuous dark and de-etiolation, and mechanical injury, were investigated in important agricultural plants. Significantly higher GSNOR activity was found under normal conditions in leaves of Cucumis spp. genotype sensitive to biotrophic pathogen Golovinomyces cichoracearum. GSNOR activity was generally increased in all studied plants by all types of stress conditions. Strong down-regulation of GSNOR was observed in hypocotyls of etiolated pea plants, which did not recover to values of green plants even 168 h after the transfer of etiolated plants to normal light regime. These results point to important role of GSNOR during normal plant development and in plant responses to several types of abiotic stress conditions.  相似文献   
147.
Interleukin 6 (IL-6) is a class-I helical cytokine with a broad spectrum of biological activities and a gene structure conserved throughout vertebrates, with five coding exons. IL-6 from European rabbits belonging to the subspecies Oryctolagus cuniculus cuniculus was previously shown to differ from other mammals by extending an additional 27 amino acids. However, in other leporids (Sylvilagus spp and Lepus spp) that diverged from the European rabbit ~12 million years ago this mutation was not present. In this study, we extended the study of IL-6 for the Oryctolagus cuniculus algirus subspecies and five additional lagomorphs’ genera (Brachylagus, Bunolagus, Pentalagus, Romerolagus, and Ochotona). We confirmed the presence of the mutated stop codon in both O. c. cuniculus and O. c. algirus. We found that the typical stop codon is present in Sylvilagus bachmani and Lepus europaeus, in agreement with previous reports, but also in Bunolagus, Brachylagus, and Ochotona. Remarkably, in Pentalagus we detected a deletion of the stop codon causing an extension of IL-6 for 17 extra residues. Our results indicate that the IL-6 extension in those species occurred by two independent events: one occurred between 2 and 8 million years ago in the ancestral of the Oryctolagus subspecies, and the other occurred in a Pentalagus ancestral at a maximum of 9 million years ago. The absence of this IL-6 extension in Bunolagus, sister genus of Oryctolagus, shows that this evolutionary event happened by convergence suggesting some functional relevance.  相似文献   
148.
Artificial evolution experiments typically use libraries of ∼1015 sequences and require multiple rounds of selection to identify rare variants with a desired activity. Based on the simple structures of some aptamers and nucleic acid enzymes, we hypothesized that functional motifs could be isolated from significantly smaller libraries in a single round of selection followed by high-throughput sequencing. To test this idea, we investigated the catalytic potential of DNA architectures in which twelve or fifteen randomized positions were embedded in a scaffold present in all library members. After incubating in either the presence or absence of lead (which promotes the nonenzymatic cleavage of RNA), library members that cleaved themselves at an RNA linkage were purified by PAGE and characterized by high-throughput sequencing. These selections yielded deoxyribozymes with activities 8- to 30-fold lower than those previously isolated under similar conditions from libraries containing 1014 different sequences, indicating that the disadvantage of using a less diverse pool can be surprisingly small. It was also possible to elucidate the sequence requirements and secondary structures of deoxyribozymes without performing additional experiments. Due to its relative simplicity, we anticipate that this approach will accelerate the discovery of new catalytic DNA and RNA motifs.  相似文献   
149.

Background

Patients with cervical dystonia (CD) present with an impaired performance of voluntary neck movements, which are usually slow and limited. We hypothesized that such abnormality could involve defective preparation for task execution. Therefore, we examined motor preparation in CD patients using the StartReact method. In this test, a startling auditory stimulus (SAS) is delivered unexpectedly at the time of the imperative signal (IS) in a reaction time task to cause a faster execution of the prepared motor programme. We expected that CD patients would show an abnormal StartReact phenomenon.

Methods

Fifteen CD patients and 15 age matched control subjects (CS) were asked to perform a rotational movement (RM) to either side as quick as possible immediately after IS perception (a low intensity electrical stimulus to the II finger). In randomly interspersed test trials (25%) a 130 dB SAS was delivered simultaneously with the IS. We recorded RMs in the horizontal plane with a high speed video camera (2.38 ms per frame) in synchronization with the IS. The RM kinematic-parameters (latency, velocity, duration and amplitude) were analyzed using video-editing software and screen protractor. Patients were asked to rate the difficulty of their RMs in a numerical rating scale.

Results

In control trials, CD patients executed slower RMs (repeated measures ANOVA, p<0.10−5), and reached a smaller final head position angle relative to the midline (p<0.05), than CS. In test trials, SAS improved all RMs in both groups (p<0.10−14). In addition, patients were more likely to reach beyond their baseline RM than CS (χ2, p<0.001) and rated their performance better than in control trials (t-test, p<0.01).

Conclusion

We found improvement of kinematic parameters and subjective perception of motor performance in CD patients with StartReact testing. Our results suggest that CD patients reach an adequate level of motor preparation before task execution.  相似文献   
150.
Resolution 19 of the 54th World Health Assembly (WHA-54.19) urged member nations to promote preventive measures, ensure treatment and mobilize resources for control of schistosomiasis and soil-transmitted helminthiases (STH). The minimum target is to attend 75% of all school-age children at risk by year 2010. The Brazilian Ministry of Health (MoH) recommends biennial surveys of whole communities and treatment of the positives through the Schistosomiasis Control Program within the Unified Health System (PCE-SUS). However, by 2004 the PCE-SUS had covered only 8.4% of the 1.2 million residents in the Rainforest Zone of Pernambuco (ZMP). Six of the 43 municipalities still remained unattended. Only three of the municipalities already surveyed reached coverage of 25% or more. At least 154 thousand children in the 7-14 years old range have to be examined (and treated if positive) within the next five years to attend the minimum target of the WHA 54.19 for the ZMP. To make this target feasible, it is suggested that from 2006 to 2010 the PCE-SUS actions should be complemented with school-based diagnosis and treatment, involving health and educational organs as well as community associations to include both children in schools and non-enrolled school-age children.  相似文献   
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