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51.
Kote-Jarai Z Olama AA Giles GG Severi G Schleutker J Weischer M Campa D Riboli E Key T Gronberg H Hunter DJ Kraft P Thun MJ Ingles S Chanock S Albanes D Hayes RB Neal DE Hamdy FC Donovan JL Pharoah P Schumacher F Henderson BE Stanford JL Ostrander EA Sorensen KD Dörk T Andriole G Dickinson JL Cybulski C Lubinski J Spurdle A Clements JA Chambers S Aitken J Gardiner RA Thibodeau SN Schaid D John EM Maier C Vogel W Cooney KA Park JY Cannon-Albright L Brenner H Habuchi T Zhang HW Lu YJ Kaneva R 《Nature genetics》2011,43(8):785-791
Prostate cancer (PrCa) is the most frequently diagnosed male cancer in developed countries. We conducted a multi-stage genome-wide association study for PrCa and previously reported the results of the first two stages, which identified 16 PrCa susceptibility loci. We report here the results of stage 3, in which we evaluated 1,536 SNPs in 4,574 individuals with prostate cancer (cases) and 4,164 controls. We followed up ten new association signals through genotyping in 51,311 samples in 30 studies from the Prostate Cancer Association Group to Investigate Cancer Associated Alterations in the Genome (PRACTICAL) consortium. In addition to replicating previously reported loci, we identified seven new prostate cancer susceptibility loci on chromosomes 2p11, 3q23, 3q26, 5p12, 6p21, 12q13 and Xq12 (P = 4.0 × 10(-8) to P = 2.7 × 10(-24)). We also identified a SNP in TERT more strongly associated with PrCa than that previously reported. More than 40 PrCa susceptibility loci, explaining ~25% of the familial risk in this disease, have now been identified. 相似文献
52.
C. Y. Heah H. Kamarudin A. M. Mustafa Al Bakri M. Bnhussain M. Luqman I. Khairul Nizar C. M. Ruzaidi Y. M. Liew 《矿物冶金与材料学报》2013,20(3):313-322
Kaolin geopolymers were produced by the alkali-activation of kaolin with an activator solution (a mixture of NaOH and sodium silicate solutions). The NaOH solution was prepared at a concentration of 6–14 mol/L and was mixed with the sodium silicate solution at a Na2SiO3/NaOH mass ratio of 0.24 to prepare an activator solution. The kaolin-to-activator solution mass ratio used was 0.80. This paper aimed to analyze the effect of NaOH concentration on the compressive strength of kaolin geopolymers at 80℃ for 1, 2, and 3 d. Kaolin geopolymers were stable in water, and strength results showed that the kaolin binder had adequate compressive strength with 12 mol/L of NaOH concentration. When the NaOH concentration increased, the SiO2/Na2O decreased. The increased Na2O content enhanced the dissolution of kaolin as shown in X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) analyses. However, excess in this content was not beneficial for the strength development of kaolin geopolymers. In addition, there was the formation of more geopolymeric gel in 12 mol/L samples. The XRD pattern of the samples showed a higher amorphous content and a more geopolymer bonding existed as proved by FTIR analysis. 相似文献
53.
Neveen S. Gadallah Ahmed M. Soliman Usama M. Abu El-Ghiet Tarek Y. Elsheikh Hathal M. Al Dhafer 《Journal of Natural History》2018,52(31-32):2071-2096
The family Leucospidae (Hymenoptera: Chalcidoidea) from Saudi Arabia is reviewed. Specimens were mainly collected from the south-western region of the country – Raydah (Abha, Asir), Sajid (Farasan Islands, Jazan) and Wadi Tourabah (Mandaq, Al Baha); and from Egypt – Wadi Khoshb (Sinai Peninsula), as well as a specimen (Leucospis elegans Klug) deposited in the Efflatoun Bey collection, Cairo University, Egypt. The genus Micrapion Kriechbaumer is here recorded for the first time from the fauna of the Arabian Peninsula, with a single species, M. clavaforme. Leucospis arabica Gadallah and Soliman sp. nov. (dorsigera group) is described. Leucospis africana (elegans group) is also newly recorded from the Saudi Arabian fauna, in addition to L. elegans which has been previously recorded. An illustrated key and a list of all leucospid species recorded and expected to occur in Saudi Arabia are provided.
www.zoobank.org/lsid:Zoobank.org:pub:40BEF37F-0D92-4AEF-9990-30C1CFC3A7A7 相似文献
54.
Magdi S. El-Hawagry Mahmoud S. Abdel-Dayem Hathal M. Al Dhafer 《Journal of Natural History》2018,52(21-22):1377-1393
A total of 80 fly species (Insecta: Diptera) belonging to 66 genera, and representing 26 families was identified from three natural areas or ‘Rawdhats’ in the Riyadh Region of the Kingdom of Saudi Arabia (KSA). The Rawdhats surveyed are Al-Harmaliyah (Al Quwayiyah Province), Al-Sabalah (Azulfi Province) and Farshet Sheaal (Al Aflaj Province). One family, one subfamily, 11 genera and 18 species were recorded for the first time from KSA, namely: the family Trixoscelididae; the subfamily Suilliinae (Heleomyzidae); the genera Oligodranes (Bombyliidae), Pseudomphrale (Scenopinidae), Actorthia (Therevidae), Crossopalpus (Hybotidae), Scatella (Ephydridae), Suillia (Heleomyzidae), Trixoscelis (Trixoscelididae), Renocera [Sciomyzidae], Melanophora and Stevenia [Rhinophoridae], Miltogramma [Sarcophagidae]; and the species Eremisca heleni (Efflatoun) and Ommatius tenellus van der Wulp [Asilidae], Oligodranes sp. [Bombyliidae], Pseudomphrale flavoscutellata Kröber [Scenopinidae], Actorthia lacteipennis (Becker), Actorthia sp. and Efflatouniella sinatica Mohammad and Badrawy [Therevidae], Crossopalpus hirsutipes Collin [Hybotidae], Eumerus mucidus Bezzi [Syrphidae], Ephydra riparia Fallén and Scatella sp. [Ephydridae], Suillia apicalis (Loew) [Heleomyzidae], Trixoscelis sp. (Trixoscelididae) and Renocera pallida (Fallén) [Sciomyzidae], Goniurellia longicauda Freidberg [Tephritidae], Melanophora sp. and Stevenia sp. [Rhinophoridae], and Miltogramma sp. [Sarcophagidae]. The zoogeographic affinities of the identified species showed a closer affiliation with the Palaearctic Region (26%) than to the Afrotropical Region (12.5%), while about 16% of the species were of both Afrotropical and Palaearctic affinities. Elements from other regions were apparently absent. The result support the idea that the central Arabian Desert which includes our study area is a transitional zone between the Palaearctic and Afrotropical regions. 相似文献
55.
56.
以冶金热力学为基础,通过实验验证建立了锰矿直接合金化效果与冶炼工艺参数间的定量关系,讨论了各因素对锰的收得率、终点锰含量的定量影响。可用此关系预见具体冶炼条件下的合金化效果。 相似文献
57.
Surfactant-decorated graphite nanoplatelets (GNPs) reinforced aluminum nanocomposites: sintering effects on hardness and wear
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Zeeshan Baig Othman Mamat Mazli Mustapha Asad Mumtaz Sadaqat Ali Mansoor Sarfraz 《矿物冶金与材料学报》2018,25(6):704-715
The exceptional properties of graphene make it ideal as a reinforcement to enhance the properties of aluminum matrices and this critically depends on uniform dispersion. In this study, the dispersion issue was addressed by sonication and non-covalent surface functionalization of graphite nanoplatelets (GNPs) using two types of surfactant: anionic (sodium dodecyl benzene sulfate (SDBS)) and non-ionic polymeric (ethyl cellulose (EC)). After colloidal mixing with Al powder, consolidation was performed at two sintering temperatures (550 and 620℃). The structure, density, mechanical and wear properties of the nanocomposite samples were investigated and compared with a pure Al and a pure GNPs/Al nanocomposite sample. Noticeably, EC-based 0.5wt% GNPs/Al samples showed the highest increment of 31% increase in hardness with reduced wear rate of 98.25% at 620℃, while a 22% increase in hardness with reduced wear rate of 96.98% at 550℃ was observed, as compared to pure Al. Microstructural analysis and the overall results validate the use of EC-based GNPs/Al nanocomposites as they performed better than pure Al and pure GNPs/Al nanocomposite at both sintering temperatures. 相似文献
58.
Al Aqeel AI 《Nature genetics》2007,39(11):1293-1298
Medical genetics involves the application of genetic knowledge and technology to specific clinical and epidemiologic concerns. Using genetics to benefit society requires that empirically verified knowledge be used within an ethical framework that combines appeal to written precedent with sensitivity to the options of individuals and families dealing with choices and necessities within the laws, norms and traditions of their society. Islamic bioethics is derived from a combination of principles, duties and rights, and to a certain extent a call to virtue, ihsan. It emphasizes prevention, and it teaches that the patient must be treated with respect and compassion and that the physical, mental and spiritual dimensions of the illness experience must be taken into account. Strategic planning for the prevention and care of genetic disorders, and for genomic research, within the context of Islamic religion and culture is promising and may provide lessons to the developed world. Islamic bioethics provides fundamental principles for genetic counseling, particularly in regard to consanguinity, which was part of the Arabian culture long before Islam but which was discouraged by the second Islamic khalifa. These fundamental principles are important for implementing many preventive and genomic research programs and for maintaining flexibility to respond to new biomedical technologies. 相似文献
59.
Eeles RA Kote-Jarai Z Giles GG Olama AA Guy M Jugurnauth SK Mulholland S Leongamornlert DA Edwards SM Morrison J Field HI Southey MC Severi G Donovan JL Hamdy FC Dearnaley DP Muir KR Smith C Bagnato M Ardern-Jones AT Hall AL O'Brien LT Gehr-Swain BN Wilkinson RA Cox A Lewis S Brown PM Jhavar SG Tymrakiewicz M Lophatananon A Bryant SL;UK Genetic Prostate Cancer Study Collaborators;British Association of Urological Surgeons' Section of Oncology;UK ProtecT Study Collaborators Horwich A Huddart RA 《Nature genetics》2008,40(3):316-321
Prostate cancer is the most common cancer affecting males in developed countries. It shows consistent evidence of familial aggregation, but the causes of this aggregation are mostly unknown. To identify common alleles associated with prostate cancer risk, we conducted a genome-wide association study (GWAS) using blood DNA samples from 1,854 individuals with clinically detected prostate cancer diagnosed at =60 years or with a family history of disease, and 1,894 population-screened controls with a low prostate-specific antigen (PSA) concentration (<0.5 ng/ml). We analyzed these samples for 541,129 SNPs using the Illumina Infinium platform. Initial putative associations were confirmed using a further 3,268 cases and 3,366 controls. We identified seven loci associated with prostate cancer on chromosomes 3, 6, 7, 10, 11, 19 and X (P = 2.7 x 10(-8) to P = 8.7 x 10(-29)). We confirmed previous reports of common loci associated with prostate cancer at 8q24 and 17q. Moreover, we found that three of the newly identified loci contain candidate susceptibility genes: MSMB, LMTK2 and KLK3. 相似文献
60.
J. Fuska M. Podojil Alžbeta Fusková Z. Vaněk 《Cellular and molecular life sciences : CMLS》1974,30(4):403-404
Zusammenfassung In-vitro-Nachweis der Hemmung der Proteo- und Nukleosynthese in den EAC-Zellen, sowie des Wachstums der HeLa-Zellen mit folgenden Derivaten des Tetrazyklins: Anhydrotetrazyklin, 4, 12-Anhydrodedimethylaminotetrazyklin und 12-Deoxydedimethylaminotetrazyklin. 相似文献