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171.

Background  

Parkinson's disease (PD) is the second most common neurodegenerative disorder. As there is no definitive diagnostic test, its diagnosis is based on clinical criteria. Recently transcranial duplex scanning (TCD) of the substantia nigra in the brainstem has been proposed as an instrument to diagnose PD. We and others have found that TCD scanning of substantia nigra duplex is a relatively accurate diagnostic instrument in patients with parkinsonian symptoms. However, all studies on TCD so far have involved well-defined, later-stage PD patients, which will obviously lead to an overestimate of the diagnostic accuracy of TCD.  相似文献   
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Tomato (Solanum lycopersicum L.) is called ‘the poor man’s orange’ due to its low price and improved nutritional values. An experiment was conducted to study the breeding potential of some exotic tomato lines by assessing various qualitative and quantitative traits conferring yield and quality attributes. Among the qualitative traits, greater variability was observed for growth type, stem hairiness, and fruit shape and size. A determinate growth habit was observed in the genotype AVTO9802 while the genotype AVTO0102 produced yellow color fruits. A significant (p ≤ 0.01) variation was also observed for the studied quantitative traits. Based on yield and traits attributed to yield, the genotypes AVTO0314, GPB0107, GPB0120 and AVTO9802 were selected as promising genotypes. The differences between the genotypic and phenotypic coefficients of variation (GCV and PCV) of the studied quantitative traits were very low. This suggests that the apparent variation was mainly due to the genotypes. The higher GCV and PCV values were observed for the number of primary branches plant−1 (NPB), number of fruits cluster−1 (NFC), individual fruit weight (IFW) and total soluble solids (TSS). High heritability was recorded for all quantitative traits in a broad sense. However, the individual fruit diameter showed the highest heritability (99.56). The highest (102.75) genetic advance (GA) was observed for the number of fruits plant−1 (NFP). High heritability coupled with high GA as percentage of mean were recorded for the traits NFP, NFC, fruit yield plant−1 (FYP) and IFW. FYP showed a significant positive correlation with NFC (0.714***) and a negative correlation with days to the first harvest (−0.539***) and plant height (−0.492**). Principal component analysis revealed that the first four components explained 78.5% of the total variation among the genotypes. Thus, the promising genotypes (AVTO0314, GPB0107, GPB0120, AVTO9802 and AVTO0102) isolated from this study can be used for developing high-yielding and high-quality tomato varieties.  相似文献   
174.
Molecular Biology Reports - The SHANK3 gene encodes a master synaptic scaffolding protein at the excitatory synapse’s postsynaptic density, which is predominantly responsible for constructing...  相似文献   
175.
Since bivalve mussels are able to graze heavily on bacteria, in this paper it is hypothesized that when mussels are cultured with fish, the filtering efficiency of the mussels will keep the bacterial population below a certain threshold and thus assist in reducing the risk of bacterial disease outbreaks. The ability of the filter‐feeding bivalve mussel Pilsbryoconcha exilis to control Streptococcus agalactiae was tested in a laboratory‐scale tilapia culture system. Juvenile Nile tilapia (Oreochromis niloticus), the bivalve mussel as well as the bacteria were cultured at different combinations using four treatments: treatment‐1: mussel and bacteria but no fish, treatment‐2: tilapia and mussel but no bacteria, treatment‐3: tilapia and bacteria but no mussel, and treatment‐4: tilapia, mussels, and bacteria. All treatments were run in three replicates; stocking rates were 10 tilapia juveniles; five mussels; and about 3.5 × 105 colony forming units (CFU) ml?1 of bacteria in 50‐L aquaria with 40‐L volume. The mussel reduced the bacterial population by 83.6–87.1% in a 3‐week period whereas in the absence of the mussel, the bacterial counts increased by 31.5%. Oresence of the mussel also resulted in significantly higher growth and lower mortality of tilapia juveniles than when the mussel was absent. The results of this experiment suggest that the freshwater mussel P. exilis could control the population of S. agalactiae in a laboratory‐scale tilapia culture system. Future studies should focus on the dynamic interactions among fish, mussels, and bacteria as well as on how input such as feed and other organic materials affect these interactions.  相似文献   
176.
In the Americas, areas with a high risk of malaria transmission are mainly located in the Amazon Forest, which extends across nine countries. One keystone step to understanding the Plasmodium life cycle in Anopheles species from the Amazon Region is to obtain experimentally infected mosquito vectors. Several attempts to colonise Ano- pheles species have been conducted, but with only short-lived success or no success at all. In this review, we review the literature on malaria transmission from the perspective of its Amazon vectors. Currently, it is possible to develop experimental Plasmodium vivax infection of the colonised and field-captured vectors in laboratories located close to Amazonian endemic areas. We are also reviewing studies related to the immune response to P. vivax infection of Anopheles aquasalis, a coastal mosquito species. Finally, we discuss the importance of the modulation of Plasmodium infection by the vector microbiota and also consider the anopheline genomes. The establishment of experimental mosquito infections with Plasmodium falciparum, Plasmodium yoelii and Plasmodium berghei parasites that could provide interesting models for studying malaria in the Amazonian scenario is important. Understanding the molecular mechanisms involved in the development of the parasites in New World vectors is crucial in order to better determine the interaction process and vectorial competence.  相似文献   
177.
The vacuolar Na+/H+ antiporter is known to alleviate saline stress by sequestering Na+ in both wild-type Arabidopsis and rice and when over-expressed in many transgenic plants. Here we report on the effect of the NHX1 transgene on the salt tolerance properties it confers to a rice landrace and a commercial cultivar suitable for the dry winter season, but which suffers loss due to seasonal stresses, particularly in the coastal areas. The Nipponbare Na+/H+ antiporter 1.9 kb cDNA was cloned into pCAMBIA1305.1 under the control of the CaMV35S promoter and transformed into tissue-culture-responsive rice landrace Binnatoa (BA). The best-expressing transgenic line at T2 was found to be significantly tolerant at the seedling stage and was advanced to T3. The transgene was then transferred to the tissue-culture recalcitrant farmer-popular commercial rice genotype, BRRIdhan 28 (BR28) by crossing. The data generated both from semi-quantitative RT-PCR and western blot hybridization revealed that the transgene showed similar expression in the crossbred BR28 plants and BA transgenic line. Comparative stress tolerance tests, however, revealed that the BR28 crossbred lines were significantly less tolerant than its transgenic parent BA at both seedling and reproductive stages. A single successful transgenic event may therefore not show the same performance in the recipient genetic background, if introgressed by crossing.  相似文献   
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179.
Cancer cells that escape induction therapy are a major cause of relapse. Understanding metabolic alterations associated with drug resistance opens up unexplored opportunities for the development of new therapeutic strategies. Here, we applied a broad spectrum of technologies including RNA sequencing, global untargeted metabolomics, and stable isotope labeling mass spectrometry to identify metabolic changes in P-glycoprotein overexpressing T-cell acute lymphoblastic leukemia (ALL) cells, which escaped a therapeutically relevant daunorubicin treatment. We show that compared with sensitive ALL cells, resistant leukemia cells possess a fundamentally rewired central metabolism characterized by reduced dependence on glutamine despite a lack of expression of glutamate-ammonia ligase (GLUL), a higher demand for glucose and an altered rate of fatty acid β-oxidation, accompanied by a decreased pantothenic acid uptake capacity. We experimentally validate our findings by selectively targeting components of this metabolic switch, using approved drugs and starvation approaches followed by cell viability analyses in both the ALL cells and in an acute myeloid leukemia (AML) sensitive/resistant cell line pair. We demonstrate how comparative metabolomics and RNA expression profiling of drug-sensitive and -resistant cells expose targetable metabolic changes and potential resistance markers. Our results show that drug resistance is associated with significant metabolic costs in cancer cells, which could be exploited using new therapeutic strategies.  相似文献   
180.
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