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1.

Background  

This article addresses the problem of interoperation of heterogeneous bioinformatics databases.  相似文献   

2.

Background

Telomeres are tandem repeats of TTAGGG at the end of eukaryotic chromosomes that play a key role in preventing chromosomal instability. The aim of the present study is to determine telomere length using fluorescence in situ hybridisation (FISH) on cytological specimens.

Methods

Aspiration samples (n = 41) were smeared on glass slides and used for FISH.

Results

Telomere signal intensity was significantly lower in positive cases (cases with malignancy, n = 25) as compared to negative cases (cases without malignancy, n = 16), and the same was observed for centromere intensity. The difference in DAPI intensity was not statistically significant. The ratio of telomere to centromere intensity did not show a significant difference between positive and negative cases. There was no statistical difference in the signal intensities of aspiration samples from ascites or pleural effusion (n = 23) and endoscopic ultrasound‐guided FNA samples from the pancreas (n = 18).

Conclusions

The present study revealed that telomere length can be used as an indicator to distinguish malignant and benign cells in cytological specimens. This novel approach may help improve diagnosis for cancer patients.  相似文献   

3.
Wang L  Lin Y  Yang L  Yu P  Xie Z  Luo Y 《Biotechnology letters》2011,33(5):943-946

Purpose of work  

This study was to demonstrate the degradation effectiveness and application potential of Candida tropicalis JH8.  相似文献   

4.

Aims

Virus detection has often been difficult due to a low concentration in water. In this study, we developed a new procedure based on concentration of virus particles on an innovative support: poly‐l ‐lysine dendrigrafts (DGL), coupled with directed nucleic acid extraction and real‐time PCR quantification.

Methods and Results

This method was evaluated using the bacteriophage MS2 as a model virus. This virus exhibited the size and structural properties of human pathogenic enteric viruses and has often been used to assess new supports of concentration. Moreover, this bacteriophage is also a faecal contamination indicator. In this study, many water filtration conditions were tested (volume of water, concentration, etc.), and more than 80% of bacteriophage were recovered after filtration on polymer, in most conditions. We demonstrated that the method was linear (slope = 0·99 ± 0·04 and Y intercept when x = ?0·02 ± 0·28), valid (as manipulators, tested concentrations, volumes of sample and batch of polymer did not have any influence on concentration) and sensitive (allowing to concentrate up to 16 600‐fold 1 l of sample and to detect and quantify down to 750 GC l?1 and 7500 GC l?1, respectively).

Conclusions

To conclude, this support exhibits high interest to retain viruses and to allow to detect low concentration of virus in water.

Significance and Impact of the Study

This study gives valuable advance in the methods of concentration and diagnosis of virus in water.  相似文献   

5.

Background  

This study was undertaken to determine the optimal cut-off value for FSH to predict the presence of spermatogenesis in patients with non-obstructive azoospermia.  相似文献   

6.

Aims

This study aimed to characterize the impact of lytic and temperate bacteriophages on the genetic and phenotypic diversity of Mannheimia haemolytica from feedlot cattle.

Methods and Results

Strictly lytic phages were not detected from bovine nasopharyngeal (n = 689) or water trough (n = 30) samples, but Myoviridae‐ or Siphoviridae‐like phages were induced from 54 of 72 M. haemolytica strains by mitomycin C, occasionally from the same strain. Phages with similar restriction fragment length polymorphism profiles (RFLP ≥70% relatedness) shared common host serotypes 1 or 2 (< 0·000 1). Likewise, phages with similar RFLP tended to occur in genetically related host bacteria (70–79% similarity). Host range assays showed that seven phages from host serotypes 1, 2 and 6 lysed representative strains of serotypes 1, 2 or 8. The genome of vB_MhM_1152AP from serotype 6 was found to be collinear with P2‐like phage φMhaA1‐PHL101.

Conclusions

Prophages are a significant component of the genome of M. haemolytica and contribute significantly to host diversity. Further characterization of the role of prophage in virulence and persistence of M. haemolytica in cattle could provide insight into approaches to control this potential respiratory pathogen.

Significance and Impact of the Study

This study demonstrated that prophages are widespread within the genome of M. haemolytica isolates and emphasized the challenge of isolating lytic phage as a therapeutic against this pathogen.  相似文献   

7.

Background  

This study was performed to examine whether patients with type 2 diabetes have cognitive deficits associated with the prefrontal cortex (PFC).  相似文献   

8.

Introduction  

This study was undertaken to determine whether the anti-osteoarthritis drug pentosan polysulfate (PPS) influenced mesenchymal precursor cell (MPC) proliferation and differentiation.  相似文献   

9.

Background  

This study attempted to replicate Luminex experimental results for large numbers of beads per classifier using multiplexed assays and routine instrument use conditions.  相似文献   

10.

Background  

This cross-sectional and prospective study used a variety of psychological inventories to evaluate the relationship between psychosocial factors and the glycemic control of patients with type 2 diabetes.  相似文献   

11.

Background  

This study assesses the behavioural and socio-economic factors associated with avoiding mosquitoes and preventing malaria in urban environments in Kenya.  相似文献   

12.

Background  

This paper presents results of a pursuit of a repeatable and objective methodology of analysis of the electroencephalographic (EEG) time series.  相似文献   

13.

Aims

This work aims to demonstrate the presence of several genes and factors associated with virulence in strains isolated from the environment at Pueblo Viejo Lagoon, State of Veracruz, Mexico.

Methods and Results

In this study, we investigated the production of V. vulnificus virulence factors, as cytolysin (haemolysin), RTX toxin, metalloprotease, siderophores, capsular polysaccharide, adhesion structures (like type IV pili), and polar and lateral flagella, involved in swimming and swarming (or, at least, the presence of genes encoding some of them) in 40 strains of V. vulnificus isolated from water and food. The results indicate that strains of environmental origin possess potential virulence characteristics.

Conclusions

Caution should be exercised when consuming raw shellfish (especially by those more susceptible risk groups).

Significance and Impact of the Study

This is the first work focused on the evaluation of V. vulnificus virulence factors in Mexico.  相似文献   

14.

Background

The physiological mechanisms that allow for sleeping in a vertical position, which is primordial for arboreal primates, have not been studied yet.

Methods

A non‐invasive polysomnographic study of 6 spider monkeys (Ateles geoffroyi) was conducted. The relative beta power of the motor cortex and its linear relation with muscle tone in the facial mentalis muscle and the abductor caudae medialis muscle of the tail during wakefulness and sleep stages were calculated.

Results

A strong negative linear relationship (= ?.8, = .03) was found between the relative power of the beta2 band in the left motor cortex and abductor caudae medialis muscle tone during delta sleep.

Conclusions

The left motor cortex, through beta2 band activity, interacts with abductor caudae medialis muscle tonicity during delta sleep. This interaction takes part in the mechanisms that regulate the sleep postures.  相似文献   

15.

Background  

This study aimed to investigate the long-term mortality and recurrence rate of stroke in first-time stroke patients with symptomatic isolated middle cerebral artery disease (MCAD) under medical management.  相似文献   

16.

Background  

This study aimed at investigating a potential effect caused by coccidia on the immune response to vaccine- and very virulent infectious bursal disase virus (vvIBDV) in SPF chickens.  相似文献   

17.

Aim

Reconstruct the long‐term ecosystem dynamics of the region across an elevational gradient as they relate to climate and local controls. In particular, we (1) describe the dominant conifers' history; (2) assess changes in vegetation composition and distribution; and (3) note periods of abrupt change versus stability as means of better understanding vegetation responses to environmental variability.

Location

Greater Yellowstone Ecosystem (GYE; USA).

Time period

16.5 ka bp ‐present.

Major taxa studied

Juniperus, Picea, Abies, Pinus, Pseudotsuga.

Methods

The vegetation reconstruction was developed from 15 pollen records. Results were interpreted based on modern pollen–vegetation relationships estimated from a suite of regression‐based approaches.

Results

Calibrated pollen data suggest that late‐glacial vegetation, dominated by shrubs and Juniperus, lacks a modern counterpart in the area. Picea, Abies and Pinus expanded at 16 ka bp in association with postglacial warming and co‐occurred in mixed‐conifer parkland/forest after 12 ka bp . This association along with Pinus contorta forest, which was present after 9 ka bp , has persisted with little change at middle and high elevations to the present day. This stability contrasts with the dynamic history of plant communities at low elevations, where shifts between parkland, steppe and forest over the last 8,000 years were likely driven by variations in effective moisture and fire.

Main conclusions

The postglacial vegetation history of the GYE highlights the dynamic nature of mountain ecosystems and informs on their vulnerability to future climate change: (1) most of the conifers have been present in the area for >12,000 years and survived climate change by adjusting their elevational ranges; (2) some plant associations have exhibited stability over millennia as a result of nonclimatic controls; and (3) present‐day forest cover is elevationally more compressed than at any time in history, probably due to the legacy of the Medieval Climate Anomaly and the Little Ice Age.  相似文献   

18.

Background  

Real-time forecasting of epidemics, especially those based on a likelihood-based approach, is understudied. This study aimed to develop a simple method that can be used for the real-time epidemic forecasting.  相似文献   

19.

Background  

Digital watermarking is a technique of hiding specific identification data for copyright authentication. This technique is adapted here for interleaving patient information with medical images, to reduce storage and transmission overheads.  相似文献   

20.

Aim

This study provides regional estimates of forest cover in dry African ecoregions and the changes in forest cover that occurred there between 1990 and 2000, using a systematic sample of medium‐resolution satellite imagery which was processed consistently across the continent.

Location

The study area corresponds to the dry forests and woodlands of Africa between the humid forests and the semi‐arid regions. This area covers the Sudanian and Zambezian ecoregions.

Methods

A systematic sample of 1600 Landsat satellite imagery subsets, each 20 km × 20 km in size, were analysed for two reference years: 1990 and 2000. At each sample site and for both years, dense tree cover, open tree cover, other wooded land and other vegetation cover were identified from the analysis of satellite imagery, which comprised multidate segmentation and automatic classification steps followed by visual control by national forestry experts.

Results

Land cover and land‐cover changes were estimated at continental and ecoregion scales and compared with existing pan‐continental, regional and local studies. The overall accuracy of our land‐cover maps was estimated at 87%. Between 1990 and 2000, 3.3 million hectares (Mha) of dense tree cover, 5.8 Mha of open tree cover and 8.9 Mha of other wooded land were lost, with a further 3.9 Mha degraded from dense to open tree cover. These results are substantially lower than the 34 Mha of forest loss reported in the FAO's 2010 Global Forest Resources Assessment for the same period and area.

Main conclusions

Our method generates the first consistent and robust estimates of forest cover and change in dry Africa with known statistical precision at continental and ecoregion scales. These results reduce the uncertainty regarding vegetation cover and its dynamics in these previously poorly studied ecosystems and provide crucial information for both science and environmental policies.  相似文献   

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