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351.
Ammad Ahmad Farooqi Ali Naqi Muhammad Zahid Qureshi Aamir Rana Ammara Khan Asma M. Riaz Syed Muhammad Faheem Afzal Nabeelah Rasheed Shahzad Bhatti 《Cell biochemistry and function》2012,30(7):611-617
Research on prostate cancer progression has focused extensively on the concept of miRNA, which can operate either as promoters or as suppressors of carcinogenesis. Moreover, recent genetic studies and emerging functional work show that strikingly similar and overlapping pathways are involved in prostate carcinogenesis. Unswervingly, these elements constitute a recently explored ‘network of networks’ that dynamically reorganizes during DNA damage and is responsible for positively or negatively regulating genome organization and integrity. We consider these facets of convergence and discuss how insights from diametrically opposed interactions of ataxia–telangiectasia mutated and mitrons can inform us about, and possibly help us to get a step closer to personalized medicine. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
352.
Platelet‐derived growth factor (PDGF) signalling in cancer: rapidly emerging signalling landscape 下载免费PDF全文
Platelet‐derived growth factor (PDGF)‐mediated signalling has emerged as one of the most extensively and deeply studied biological mechanism reported to be involved in regulation of growth and survival of different cell types. However, overwhelmingly increasing scientific evidence is also emphasizing on dysregulation of spatio‐temporally controlled PDGF‐induced signalling as a basis for cancer development. We partition this multi‐component review into recently developing understanding of dysregulation PDGF signalling in different cancers, how PDGF receptors are quantitatively controlled by microRNAs. Moreover, we also summarize most recent advancements in therapeutic targeting of PDGFR as evidenced by preclinical studies. Better understanding of the PDGF‐induced intracellular signalling in different cancers will be helpful in catalysing the transition from a segmented view of cancer biology to a conceptual continuum. 相似文献
353.
354.
The epifaunal assemblage was evaluated at three different depths (5, 15 and 25 m) in the inshore waters of Pazhayar, Parangipettai
and Cuddalore apart from 5 m depth near SIPCOT covering totally 10 stations (11°21′ N to 11°42′ N; 79°46′49″ E to 79°52′34″
E) in the southeast coast of India, Bay of Bengal. The occurrence of as many as 112 species belonging to 6 groups was recorded.
Among these, gastropods constituted the largest component (42.85%) with 48 species. Bivalves came next with the percentage
contribution of 24.10% with 27 species. Crustaceans and polychaetes contributed with 16.96% (19 species) and 6.25% (7 species),
respectively. Others contributed with 9.82% (11 species). The maximum number of species was recorded in Cuddalore transect
(65 species) and the minimum in SIPCOT (20 species). The maximum abundance was recorded in SIPCOT (1363 ind./haul) but the
diversity was found to be lower here than in the other stations. The bivalve, Scapharca inaequivalvis was abundant only in this station whereas the large sized polychaetes, Epidiopatra hupferiana monroi and Sternaspis scutata were found only in the Pazhayar transect during all the seasons. Multivariate analyses were done to define assemblages. The
total number of species estimated by various extrapolators varied from 112 species to 169.73 species. The cluster analysis
revealed the gradual change in species composition with increase in depth. In the principal coordinate analysis (PCO) the
first two axes explained 49.8% of the total variability in the case of biota and 98.3% of the total variability in the case
of environmental variables. The distance based linear model (DISTLM) was used to find out the relationship between the abundance
of epifauna and environmental variables. Depth explained about 23.7% of the variability while temperature and pH explained
17.5 and 10.6%, respectively. The best solution suggested all the nine environmental variables to combinedly explain about
92.49% of the total variability 相似文献
355.
Oliver D. Howes Thomas Whitehurst Ekaterina Shatalina Leigh Townsend Ellis Chika Onwordi Tsz Lun Allenis Mak Atheeshaan Arumuham Oisín OBrien Maria Lobo Luke Vano Uzma Zahid Emma Butler Martin Osugo 《World psychiatry》2021,20(1):75-95
The idea that a longer duration of untreated psychosis (DUP) leads to poorer outcomes has contributed to extensive changes in mental health services worldwide and has attracted considerable research interest over the past 30 years. However, the strength of the evidence underlying this notion is unclear. To address this issue, we conducted an umbrella review of available meta‐analyses and performed a random‐effects meta‐analysis of primary studies. MEDLINE, Web of Science, PsycINFO and EMBASE were searched from inception to September 3, 2020 to identify relevant meta‐analyses of studies including patients with schizophrenia spectrum disorders, first‐episode psychosis, or affective and non‐affective psychosis. Thirteen meta‐analyses were included, corresponding to 129 individual studies with a total sample size of 25,657 patients. We detected potential violations of statistical assumptions in some of these meta‐analyses. We therefore conducted a new random‐effects meta‐analysis of primary studies. The association between DUP and each outcome was graded according to a standardized classification into convincing, highly suggestive, suggestive, weak, or non‐significant. At first presentation, there was suggestive evidence for a relationship between longer DUP and more severe negative symptoms (beta=–0.07, p=3.6×10–5) and higher chance of previous self‐harm (odds ratio, OR=1.89, p=1.1×10–5). At follow‐up, there was highly suggestive evidence for a relationship between longer DUP and more severe positive symptoms (beta=–0.16, p=4.5×10–8), more severe negative symptoms (beta=–0.11, p=3.5×10–10) and lower chance of remission (OR=2.16, p=3.0×10–10), and suggestive evidence for a relationship between longer DUP and poorer overall functioning (beta=–0.11, p=2.2×10–6) and more severe global psychopathology (beta=–0.16, p=4.7×10–6). Results were unchanged when analysis was restricted to prospective studies. These effect sizes are clinically meaningful, with a DUP of four weeks predicting >20% more severe symptoms at follow‐up relative to a DUP of one week. We conclude that DUP is an important prognostic factor at first presentation and predicts clinically relevant outcomes over the course of illness. We discuss conceptual issues in DUP research and methodological limitations of current evidence, and provide recommendations for future research. 相似文献
356.
The present study investigated the spawning behaviour of the spiny eel, Macrognathus pancalus, and its relationship with the environment (photoperiod and temperature). The results show that M. pancalus breeds during February to September with peak spawning during February/March and July/August, indicating two main breeding periods. Initiation of breeding occurs during increasing day lengths in early spring (February/March), and regression during decreasing day lengths in autumn (September/October). The breeding status confirmed by gonadosomatic index (GSI) and ovarian histology showed six stages of ovarian maturation (viz. stage I: chromatin nucleaolar; II: perinucleolar; III: cortical alveolar; IV: vitellogenesis; V: ripe; and VI: partially spent), with predominance of one or more stages at a particular time of the year. Males also followed a similar seasonal pattern in gonadal maturation as reflected by their GSI. Results show that M. pancalus is a seasonal breeder with bimodal spawning activity. The breeding pattern suggests an influence of prevailing day length conditions at this latitude. 相似文献
357.
Kashif Rashid Muhammad Akhtar Kaiser Latif Cheema Irfan Rasool Muhammad Afzal Zahid Amer Hussain Zeeshan Qadeer Muhammad Jahanzaib Khalid 《Saudi Journal of Biological Sciences》2021,28(1):1063
The effect of fertilizer on yield and yield related traits studied in two consecutive years at two different locations. Three different doses of fertilizer (NPK) applied at the rate of 9:23:0, 18:46:12 and 27:69:25 respectively on sixteen chickpea, genotypes (Desi and Kabuli advance lines and commercial varieties). Data recorded for days to 50% flowering, plant height, primary and secondary branches, pods per plant, 100-grain weight and grain yield (kg/ha). In Desi chickpea highest grain yield (kg/ha) in both years was produced by advance line D-12026 and in Kabuli advance line K-70005 at Faisalabad location. Grain yield kg/ha had significant positive correlation with all the considered parameters except days to 50% flowering and days to 50% maturity. The treatment comparison manifested that fertilizer doses 9:23:0 enhanced grain yield. The high dose of fertilizer is not recommendable. The grain yield of Desi and Kabuli chickpea at two locations Pulses Research Institute (PRI) Faisalabad and GBRSS (Gram Breeding Research Sub Station) Kallurkot had significant variation. The grain yield (kg ha−1) was significant high in research area of PRI, Faisalabad in both years. The NPK 9:23:0 found operative dose of fertilizer for chickpea. 相似文献
358.
ZA Muchlisin Musri Musman MN Siti Azizah 《Reproductive biology and endocrinology : RB&E》2010,8(1):49
Background
Rasbora tawarensis is an endemic freshwater fish in Lake Laut Tawar, Aceh Province, Indonesia. Unfortunately, its status is regarded as critical endangered with populations decreasing in recent years. To date no information on the spawning activities of the fish are available. Therefore, this study provides a contribution to the knowledge on reproductive biology of R. tawarensis especially on spawning seasons as well as basic information for conservation of the species. 相似文献359.
The main objectives of this study were to investigate the intra-specific and inter-specific phytochemical diversity and classification of nine important medicinal plant species from Tabuk region (KSA), namely (Pulicaria undulata L., Pulicaria incisa Lam., Artemisia herba-alba Asso., Artemisia monosperma Delile, Artemisia judaica L. and Achillea fragrantissima Forssk. from Asteraceae family, Ducrosia flabellifolia Boiss. from Apiaceae family, Thymus vulgaris L. and Lavandula coronopifolia Poir. from Lamiaceae family); to evaluate the antibacterial potentials of the plant extracts, and to inspect the possible associations between phytochemical diversity and contents of different phytochemical classes with the antibacterial activities of plant extracts. GC/MS technique was used to identify phytochemicals in the plant extracts. The standard disk diffusion technique was used to conduct the antibiotic susceptibility against four pathogenic bacterial species (two Gram positive: Staphylococcus aureus and Bacillus subtilis and two Gram negative species: Pseudomonas aeruginosa and Escherichia coli. A total of 160 different phytochemicals belonging to 30 compound classes were separated and identified. A. fragrantissima had the highest phytochemical diversity and P. incisa had the lowest one. Phytochemical beta diversity was 6.2362. Ethanol outperformed other extraction solvents in terms of antibacterial activity, while Pulicaria undulata and T. vulgaris ranked highest among plants in this regard. Gram positive bacterial species were more sensitive to plant extracts compared to Gram negative species. Phytochemical diversity and antibacterial activity of plant extracts against E. coli and P. aeruginosa were positively correlative, terpenoid and benzene & substituted derivative contents exhibited significant (p<0.05) positive correlations with the antibacterial activity against E. coli, terpenoid contents also showed positive correlation with activity against P. aeruginosa; benzene & derivative showed positive correlation with activity against the rest of bacterial species, 相似文献
360.