排序方式: 共有11条查询结果,搜索用时 234 毫秒
1.
Fidelis Akunke Atuo Samuel T Ivande Zingfa J Wala Shiiwa Manu Timothy J O’Connell 《Ostrich》2016,87(2):101-112
The Grey-necked Picathartes Picathartes oreas is a globally threatened bird species in Africa with a wild population of less than 10,000 individuals. The Nigerian population, which has been poorly studied, is restricted to the forest of Cross River. This study re-assessed the distribution, breeding population, habitat use and current threats of the Grey-necked Picathartes by revisiting the 91 breeding sites identified during the first and only survey of the species in 1987. We estimated a breeding population of 164 individuals across 82 breeding sites. Only 72 breeding sites were found in the localities where 91 had been registered in 1987. Thirteen (18%) of these 72 sites were no longer active and showed evidence of human disturbance. The occurrence of Grey-necked Picathartes’ nest sites was positively predicted by higher number of emergent trees, larger rocks and negatively related to disturbance matrices. Similarly, larger colony sizes were associated with high canopy cover and rock height. Also, the probability of finding an active nest within a breeding colony was significantly predicted by increased canopy, tree density and ground cover. Human threats included farming, wire snares, egg and juvenile removal, bush burning, and hunter’s camps. These threats, though specific to the Grey-necked Picathartes, threaten the integrity of the Cross River forest habitats. 相似文献
2.
Zheng G Zhang Z Dowell C Wala E Dwoskin LP Holtman JR McIntosh JM Crooks PA 《Bioorganic & medicinal chemistry letters》2011,21(8):2476-2479
A series of azaaromatic quaternary ammonium analogs has been discovered as potent and selective α9α10 nicotinic acetylcholine receptor (nAChR) antagonists. The preliminary structure-activity relationships of these analogs suggest that increased rigidity in the linker units results in higher potency in inhibition of α9α10 nAChRs and greater selectivity over α7 nAChRs. These analogs represent a new class of analgesic for the treatment of neuropathic and tonic inflammatory pain. 相似文献
3.
Kperkouma Wala Agbélessessi Y. Woegan Wiyao Borozi Marra Dourma Abalo Atato Komlan Batawila Koffi Akpagana 《African Journal of Ecology》2012,50(3):355-366
Protected areas constitute strategy for biodiversity conservation. Unfortunately, these sanctuaries of biodiversity are submitted to a high human pressure in Togo. This study carried out in the Alédjo protected area, aimed to make an analysis of various forms of human footprints and their impact on its plant resources. Methodological approach was based on forest inventory completed by inquiries. Ninety‐four wooded species belonging to 35 families were counted. Floristic data analysis showed that seven species: Isoberlinia doka Craib & Stapf, Daniellia oliveri (Rolfe) Hutch. & Dalz., Berlinia grandiflora (Vahl) Hutch. & Dalz., Pterocarpus erinaceus Poir., Zanha golungensis Hiern, Khaya senegalensis (Desv.) A. Juss., Pentadesma butyracea Sabine was prominent. Five vegetation types were identified: riparian forests, dry forests, open forests, savanna woodlands, tree/shrub savannas with variable structural characteristics. The diversity indices in these plant communities are well significant and indicate a good distribution of species in the area. Several human activities such as fuel wood, fruits and medicinal plants gathering, carbonization, pasture were found within the protected area. Local authorities and associations are involved in the management of the protected area, but the participation of local populations needs to be improved. 相似文献
4.
Wala Ahmad Amro Wael Al-Qaisi Fawzi Al-Razem 《Journal of Genetic Engineering and Biotechnology》2018,16(1):99-103
The isolation of polyclonal antibodies from the serum of immunized mammals has significantly contributed to scientific research and diagnosis. The fact that recent technologies allow the production of antibodies in the yolk of eggs laid by hens, has led to the development of an alternative method for antibody generation that is less stressful to animals. As hens are kept under almost all their natural conditions, antibodies are isolated from the collected eggs; this technology is expected to become an interesting alternative to the conventionally serum-based techniques that eventually require to sacrifice the animal.Here we present a modified protocol for the isolation of IgY antibodies from immunized chickens and provide comparison between two chicken breeds in relative to IgY yield per egg. Our results show the possibility of generating large quantities of highly pure IgY from chicken eggs and also show large differences in the yield of IgY production between the two studied breeds. The results of this work indicate that IgY technology can be used for the production of primary antibodies for immunological work and disease diagnosis. 相似文献
5.
Najla Al Shaye Hussein Migdadi Asma Charbaji Shatha Alsayegh Shaza Daoud Wala AL-Anazi Salem Alghamdi 《Saudi Journal of Biological Sciences》2018,25(6):1007-1015
Genetic diversity among seven Saudi tomato landraces collected from different regions of the country was assessed using SDS-PAGE and molecular (sequence-related amplified polymorphism- SRAP) markers. A total of 19 alternative protein bands with different mobility rates were identified within a molecular weight range of 9.584–225?KDa, with 53% polymorphism. Specific protein bands were observed in the “Hail 548” and “Qatif 565” landraces. Genetic similarity based on Jaccard’s coefficient ranged from 0.53 to 1.00, with an average of 0.72. For molecular evaluation, 143 amplicons (fragments) were generated using 27 SRAP primer pair combinations, of which 88 were polymorphic across all the landraces. The PIC values ranged from 0.46 to 0.90, with an average of 0.76. All landraces showed an average of 0.66 similarity coefficient value. The UPGMA dendrogram supported by principal coordinate analysis (PCoA) revealed clusters of the landraces that almost corresponded to their geographical origin. Thus, seed storage protein profiling based on SDS-PAGE and SRAP markers can efficiently be used to assess genetic variability among tomato germplasms. The information obtained in the analysis will be of great interest in the management of ex situ collections for utilization in breeding programs or for direct use in quality markets. 相似文献
6.
Guillaume Gaullier Simona Miron Sabrina Pisano Rémi Buisson Yann-Va? Le?Bihan Carine Tellier-Lebègue Wala Messaoud Pierre Roblin Beatriz G. Guimar?es Robert Thai Marie-Josèphe Giraud-Panis Eric Gilson Marie-Hélène Le?Du 《Nucleic acids research》2016,44(4):1962-1976
Telomere integrity is essential to maintain genome stability, and telomeric dysfunctions are associated with cancer and aging pathologies. In human, the shelterin complex binds TTAGGG DNA repeats and provides capping to chromosome ends. Within shelterin, RAP1 is recruited through its interaction with TRF2, and TRF2 is required for telomere protection through a network of nucleic acid and protein interactions. RAP1 is one of the most conserved shelterin proteins although one unresolved question is how its interaction may influence TRF2 properties and regulate its capacity to bind multiple proteins. Through a combination of biochemical, biophysical and structural approaches, we unveiled a unique mode of assembly between RAP1 and TRF2. The complete interaction scheme between the full-length proteins involves a complex biphasic interaction of RAP1 that directly affects the binding properties of the assembly. These results reveal how a non-DNA binding protein can influence the properties of a DNA-binding partner by mutual conformational adjustments. 相似文献
7.
Peter MacPherson Emily L. Webb Wala Kamchedzera Elizabeth Joekes Gugu Mjoli David G. Lalloo Titus H. Divala Augustine T. Choko Rachael M. Burke Hendramoorthy Maheswaran Madhukar Pai S. Bertel Squire Marriott Nliwasa Elizabeth L. Corbett 《PLoS medicine》2021,18(9)
BackgroundSuboptimal tuberculosis (TB) diagnostics and HIV contribute to the high global burden of TB. We investigated costs and yield from systematic HIV-TB screening, including computer-aided digital chest X-ray (DCXR-CAD).Methods and findingsIn this open, three-arm randomised trial, adults (≥18 years) with cough attending acute primary services in Malawi were randomised (1:1:1) to standard of care (SOC); oral HIV testing (HIV screening) and linkage to care; or HIV testing and linkage to care plus DCXR-CAD with sputum Xpert for high CAD4TBv5 scores (HIV-TB screening). Participants and study staff were not blinded to intervention allocation, but investigator blinding was maintained until final analysis. The primary outcome was time to TB treatment. Secondary outcomes included proportion with same-day TB treatment; prevalence of undiagnosed/untreated bacteriologically confirmed TB on day 56; and undiagnosed/untreated HIV. Analysis was done on an intention-to-treat basis. Cost-effectiveness analysis used a health-provider perspective. Between 15 November 2018 and 27 November 2019, 8,236 were screened for eligibility, with 473, 492, and 497 randomly allocated to SOC, HIV, and HIV-TB screening arms; 53 (11%), 52 (9%), and 47 (9%) were lost to follow-up, respectively. At 56 days, TB treatment had been started in 5 (1.1%) SOC, 8 (1.6%) HIV screening, and 15 (3.0%) HIV-TB screening participants. Median (IQR) time to TB treatment was 11 (6.5 to 38), 6 (1 to 22), and 1 (0 to 3) days (hazard ratio for HIV-TB versus SOC: 2.86, 1.04 to 7.87), with same-day treatment of 0/5 (0%) SOC, 1/8 (12.5%) HIV, and 6/15 (40.0%) HIV-TB screening arm TB patients (p = 0.03). At day 56, 2 SOC (0.5%), 4 HIV (1.0%), and 2 HIV-TB (0.5%) participants had undiagnosed microbiologically confirmed TB. HIV screening reduced the proportion with undiagnosed or untreated HIV from 10 (2.7%) in the SOC arm to 2 (0.5%) in the HIV screening arm (risk ratio [RR]: 0.18, 0.04 to 0.83), and 1 (0.2%) in the HIV-TB screening arm (RR: 0.09, 0.01 to 0.71). Incremental costs were US$3.58 and US$19.92 per participant screened for HIV and HIV-TB; the probability of cost-effectiveness at a US$1,200/quality-adjusted life year (QALY) threshold was 83.9% and 0%. Main limitations were the lower than anticipated prevalence of TB and short participant follow-up period; cost and quality of life benefits of this screening approach may accrue over a longer time horizon.ConclusionsDCXR-CAD with universal HIV screening significantly increased the timeliness and completeness of HIV and TB diagnosis. If implemented at scale, this has potential to rapidly and efficiently improve TB and HIV diagnosis and treatment.Trial registrationclinicaltrials.gov .In a randomised trial, Peter MacPherson and colleagues investigate the costs, timeliness, and completeness of computer-aided X-ray screening for tuberculosis and HIV testing in adults with cough in Malawi. NCT03519425相似文献
8.
Ben Kridis-Rejeb Wala Ben Ayed-Guerfali Dorra Ammous-Boukhris Nihel Ayadi Wajdi Kifagi Chamseddine Charfi Slim Saguem Ines Sellami-Boudawara Tahia Daoud Jamel Khanfir Afef Mokdad-Gargouri Raja 《Molecular biology reports》2020,47(9):6507-6516
Molecular Biology Reports - Male Breast Cancer (MBC) is a rare and aggressive disease that is associated with genetic factors. Mutations in BRCA1 and BRCA2 account for... 相似文献
9.
Nawal Al-Henhena Rozaida Poh Yuen Ying Salmah Ismail Wala Najm Shaden A. M. Khalifa Hesham El-Seedi Mahmood Ameen Abdulla 《PloS one》2014,9(11)
Andrographis paniculata is a grass-shaped medicinal herb, traditionally used in Southeast Asia. The aim of this study was to evaluate the chemoprotective effects of A. paniculata on colorectal cancer. A. paniculata ethanol extract was tested on azoxymethane (AOM)-induced aberrant crypt foci (ACF) in vivo and in vitro. A. paniculata treated groups showed a significant reduction in the number of ACF of the treated rats. Microscopically, ACF showed remarkably elongated and stratified cells, and depletion of the submucosal glands of AOM group compared to the treated groups. Histologically, staining showed slightly elevated masses above the surrounding mucosa with oval or slit-like orifices. Immunohistochemically, expression of proliferating cell nuclear antigen (PCNA) and β-catenin protein were down-regulated in the A. paniculata treated groups compared to the AOM group. When colon tissue was homogenized, malondialdehyde (MDA) and nitric oxide (NO) levels were significantly decreased, whereas superoxide dismutase (SOD) activity was increased in the treated groups compared to the AOM group. A. paniculata ethanol extract showed antioxidant and free radical scavenging activity, as elucidated by the measure of oxidative stress markers. Further, the active fractions were assessed against cell lines of CCD841 and HT29 colon cancer cells. 相似文献
10.
Wala Ghandour Julia A. Hubbard Janet Deistung Martin N. Hughes Robert K. Poole 《Applied microbiology and biotechnology》1988,28(6):559-565
Summary Growth of Escherichia coli in chloridefree medium in batch culture is inhibited completely at concentrations of AgNO3 greater than 2.5x10-6 M. Incubation of non-growing cells in HEPES buffer (pH 7.4) at increasing levels of Ag+ results in the progressive saturation of two types of binding site. At one site, the Ag+ is not released by washing with 0.1 M nitric acid, and is probably intracellular. Silver bound to the second site is released by acid-washing, but not by buffer washing, and is assumed to be surface-bound. The amounts of Ag+ taken up from solution at the two sites is 1.6x10-7 and 4.6x10-7 mol (mg dry weight)-1, respectively. Total accumulation of silver is 67 mg (g dry weight)-1, similar to literature values found for silver-resistant bacteria. Binding of Ag+ at intracellular sites (observed at low [Ag+]) appears to be independent of pH. Addition of AgNO3 to growing cells in mid-exponential phase of growth in concentrations that will inhibit growth results in substantially decreased accumulation of silver. Growth yield in chemostat culture is diminished in the presence of added Ag+, but this effect is moderated by added Cu2+, which may protect copper sites from Ag+ or compete with Ag+ for other sites at which Ag+ exerts toxic effects. Very small amounts of Cu2+ are found in cell samples from the chemostat compared to the substantial amounts of Ag+ taken up, but uptake of Cu2+ is decreased at higher [Ag+]/[Cu2+]ratios. 相似文献