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151.
Abdulla Ahmado Hamed I. Khouja Graham J. Kemp Diane F. Guilland-Cumming R. Graham G. Russell Alan Bevington 《Cell biochemistry and function》1993,11(1):25-34
Uptake of orthophosphate (Pi) by osteoblast-like cells is known to be stimulated by parathyroid hormone (PTH), but effects on intracellular [Pi] have not been investigated. Here we show in rat osteoblast-like cells (UMR 106-06) that PTH (10?11 to 10?7 M ) increases both 32Pi uptake and cellular [Pi] by up to 50 per cent. 1,25 Dihydroxyvitamin D3 (1,25D) (10?12 to 10?6 M ) and salmon calcitonin (CT) (10?12 to 10?6 g ml?1) also increased cellular [Pi] (by up to 60 per cent), but the percentage increases in total cellular 32Pi uptake were smaller. The effects of 1,25D were transient (observable at 80 min and 6 h but not 24 h), and were also observed with 24,25 dihydroxy- and 25 hydroxyvitamin D3. Transient degradation of organic phosphorus pools to Pi might contribute to this increased [Pi]. These pools remain to be identified but were not shown to be phospholipids. Foetal bovine serum also affected cellular [Pi]. Care is therefore needed in distinguishing direct hormonal effects on cellular [Pi] from indirect effects arising from changes in the rate of cell growth. 相似文献
152.
新疆平茶渍属地衣生态分布与地理区系成分分析 总被引:2,自引:0,他引:2
根据多年的实地调查资料和前人研究资料,对新疆平茶渍属(Aspicilia)地衣的种类以及它们的分布区、区系特征进行了初步研究。结果表明,分布在新疆的平茶渍属地衣共有33种,主要分布在天山、阿勒泰山、昆仑山和准噶尔盆地。根据它们对环境的适应特征和选择性,将新疆平茶渍属地衣的地理区系划分为广布种、环极北极高山种、环极低北极及北方种、北美东部种、中亚种、中国特有种、分布范围不清楚的种等7种类型。同时把新疆平茶渍属地衣的地理分布区域划分为欧亚森林植物亚区、亚洲荒漠植物亚区、青藏高原亚区等三种分布区域。研究还发现分布在阿勒泰山、天山、昆仑山和准噶尔盆地的平茶渍属主要生长在岩石上面,生长基物比较单一。 相似文献
153.
Hernández-Quintero JD MH Reyes-Valdés DV Mendoza-Rodríguez M Gómez-Martínez R Rodríguez-Herrera 《Phyton》2015,84(1):107-112
The genus Dasylirion is a group of plants typically present in the Chihuahuan Desert, perennial, with a dioecious sexual behavior and commonly called sotoles. This genus has been little studied from the biological point of view, and the bases of its reproductive response remain unknown. In this work we studied the chromosome number and meiotic response of Dasylirion cedrosanum in the county of Saltillo, Coahuila, located at the North East of Mexico. For the preparation of mitotic chromosomes, we used a technique based on enzymatic treatment with pectolyase and cellulase, as well as staining with acetocarmin dye. For the study of meiosis, male flower buds were collected, fixed and stained for analysis with the same dye. As a result, the gametic (n = x = 19) and somatic chromosome (2n = 38) numbers of D. cedrosanum are reported for the first time, being consistent with previous findings in other Dasylirion species, which points to a constant ploidy level across the genus. Variation was observed in the morphology and size of the somatic chromosomes, with types ranging from submetacentric to subtelocentric, and sizes oscillating in a range of 4.43 µm, with an average total length of 112.38 µm for the diploid chromosome complement. This shows that the chromosome complement of D. cedrosanom would belong to a 3B classification of Stebins, with a medium variation between chromosome lengths and low chromosome asymmetry. This variation indicates the feasibility of constructing a chromosome ideotype for this species. The meiotic chromosome pairing showed a chromosome behavior consistent with a disomic inheritance characteristic of a diploid species, with prevalence of ring and chain bivalents, typically without pairing abnormalities. Bivalent configurations in all cases were symmetrical.The normal and symmetrical meiotic pairing indicates a balanced production of gametes, and suggests the absence of heteromorphic sex determination. 相似文献
154.
Shahid B. Khan Salim Javed Shakeel Ahmed Junid N. Shah Abdulla Ali Al Hammadi Eissa Ali Al Hammadi 《Zoology in the Middle East.》2017,63(3):194-201
Greater Flamingo (Phoenicopterus roseus) monitoring was undertaken in the United Arab Emirates from 2003 to 2015 at 36 permanent sites to find key wintering and breeding sites. Bul Syayeef Marine Protected Area with monthly mean of 6553 (±3594) flamingos followed by Al Wathba Wetland Reserve with 1228 (±1190) flamingos topped the list. In addition, Shahama Wetland and Al Aryam Mudflats in Abu Dhabi Emirate form a complex of four nearby sites that hold the majority of nearly 15,000–20,000 birds wintering in the country. Lagoons (Khors) in the northern emirates are the other key wintering sites, that suffer habitat destruction and high disturbance. Breeding has been sporadic and infrequent since the first breeding attempt in 1993. Greater Flamingos have bred successfully only in the Abu Dhabi Emirate on 10 occasions at three sites with the highest eight breeding attempts at Al Wathba and one each at Shahama and Bul Syayeef. A total of 1,972 young have fledged with a high overall breeding success of 43%. The highest number of 801 young fledged at Bul Syayeef in 2009 followed by 420 at Al Wathba in 2015 and 350 at Shahama in 2007. Successful breeding occurred both in summer and winter seasons, breeding attempts were more (58%) in summer compared to winter. Flamingos have bred regularly at Al Wathba Wetland Reserve since 2011, this was made possible due to the provision of an artificial island to aid nesting and better control of predators. Breeding is successful at sites that maintain higher bird numbers and are free from disturbance. 相似文献
155.
Ghada Al-Kafaji Ghazi Al-Mahroos Haifa Abdulla Al-Muhtaresh Mohamed Abdalla Sabry Rima Abdul Razzak Abdel Halim Salem 《Biomarkers》2017,22(3-4):268-278
Circulating microRNAs (miRNAs) have been shown as promising biomarkers for various diseases. We investigated the predictive potential of circulating endothelium-enriched miR-126 in type 2 diabetes patients (T2D) without chronic complications and T2D patients with coronary artery diseases (CAD). The expression levels of circulating miR-126, determined by quantitative real time PCR, were decrease in peripheral blood of T2D patients and T2D with CAD compared with healthy controls. MiR-126 strongly associated with T2D and CAD, negatively correlated with LDL in CAD patients and differentiated between T2D patients, T2D patients with CAD and healthy subjects. Circulating miR-126 may serve as a biomarker for predicting patients with T2D and diabetic CAD. 相似文献
156.
Heparinized blood samples were taken from male immature and mature camels of the Sha'alah breed, housed at the University Animal farm, during the rutting and non-rutting period. Other blood samples were also collected from camels slaughtered at defined seasons (summer, autumn, winter and spring) and from the Buraydah slaughter-house. In addition, specimens from the testes were also taken to confirm the difference between the immature and the mature animals during the non-rutting and rutting seasons. The plasma obtained from the collected blood samples was used for estimation of the following hormones, Melatonin (MLT), Follicle Stimulating Hormone (FSH), Leutinizing Hormone (LH), Testosterone and Prolactin (PRL) using the radioimmunoassay technique. Specimens of testes tissue were fixed in calcium formol, processed for histological examination using standard procedures and stained with H&E. The results clearly differentiated the samples as immature and mature during the non-rutting and rutting seasons. Commercially available human radioimmunoassay (RIA) kits for MLT, FSH, LH, testosterone and PRL were adapted for quantitation of these hormones in serum from the one-humped camel (Camelus dromedarius). Serum samples from 40 camels were assayed in order to determine possible differences between various groups in the concentrations of MLT, FSH, LH, testosterone and PRL in these animals. Among the camels, serum concentrations of melatonin, FSH, LH, testosterone and prolactin reflected age and seasonal differences. Immature camels had overall significantly lower levels in MLT, FSH, LH, testosterone and PRL. Mean FSH and LH levels from confirmed non-rutting (sexually inactive) camels were 0.22 ± 0.08 and 0.37 ± 0.18 ng/mL, respectively. Although rutting (sexually active) camels had higher FSH and LH levels, the differences were not statistically significant (P less than 0.07). Our observations indicate that these RIAs can reliably detect serum MLT, FSH, LH, testosterone and PLT from camels and represent the first quantitation of melatonin in Camilidae in correlation with FSH, LH, testosterone and prolactin. 相似文献
157.
158.
BACKGROUND: Benzo(a)pyrene (BaP), anthracene (ANTH) and chrysene (CHRY) are polynuclear aromatic hydrocarbons (PAHs) implicated in renal toxicity and carcinogenesis. These PAHs elicit cell type-specific effects that help predict toxicity outcomes in vitro and in vivo. While BaP and ANTH selectively injure glomerular mesangial cells, and CHRY targets cortico-tubular epithelial cells, binary or ternary mixtures of these hydrocarbons markedly reduce the overall cytotoxic potential of individual hydrocarbons. METHODS: To study the biochemical basis of these antagonistic interactions, renal glomerular mesangial cells were challenged with BaP alone (0.03 - 30 microM) or in the presence of ANTH (3 microM) or CHRY (3 microM) for 24 hr. Total RNA and protein will be harvested for Northern analysis and measurements of aryl hydrocarbon hydroxylase (AHH) and ethoxyresorufin-O-deethylase (EROD) activity, respectively, to evaluate cytochrome P450 mRNA and protein inducibility. Cellular hydrocarbon uptake and metabolic profiles of PAHs were analyzed by high performance liquid chromatography (HPLC). RESULTS: Combined hydrocarbon treatments did not influence the cellular uptake of individual hydrocarbons. ANTH or CHRY strongly repressed BaP-inducible cytochrome P450 mRNA and protein expression, and markedly inhibited oxidative BaP metabolism. CONCLUSION: These findings indicate that antagonistic interactions among nephrocarcinogenic PAHs involve altered expression of cytochrome P450s that modulate bioactivation profiles and nephrotoxic/ nephrocarcinogenic potential. 相似文献
159.
Abdulla YH 《BioEssays : news and reviews in molecular, cellular and developmental biology》2001,23(5):456-462
Amyloid beta precursor protein (APP) and prion protein (PrP) are cell membrane elements implicated in neurodegenerative diseases. Both proteins undergo endoproteolysis. Evidence is adduced from the literature hinting that the process in the two proteins could be related, their functions may overlap and their distributions coincide. It is proposed that PrP catalyses its own cleavage, the C-terminal fragment functions as an alpha secretase and the N-terminal segment chaperones the active site; the alpha secretase releases anticoagulant and neurotrophic ectodomains from APP. The proposals explain some features of spongiform encephalopathies. 相似文献
160.
Performance of monolayered cervical smears in a gynecology outpatient setting in Kuwait 总被引:6,自引:0,他引:6
Luthra UK Chishti M Dey P Jolly SV Abdulla M Das DK Sugathan TN Ajrawi MT George J George SS Aziz AA al-Juwaiser A Karim FA Mallik MK Sheikh ZA Khan S 《Acta cytologica》2002,46(2):303-310
OBJECTIVE: To compare ThinPrep (TP) Papanicolaou smears (Cytyc Corp., Box-borough, Massachusetts, U.S.A.) with matching conventional Papanicolaou (CP) smears for specimen adequacy, cytologic quality, diagnostic accuracy and screening time. STUDY DESIGN: In this prospective study of 1,024 women a split-sample, matched-pair design in favor of CP slides based on single-blind criteria was followed with a smear on a glass slide for CP and the remaining material collected in Preserv-Cyt solution (Cytyc) for a TP smear. A Cytobrush (Medscand, Hollywood, Florida, U.S.A.) was used for smear preparation for CP. TP smears were processed in ThinPrep 2000 (Cytyc). Smears were stained with Papanicolaou stain and were interpreted according to the Bethesda system. RESULTS: The number of satisfactory but limited (SBL) cases with TP were 77 (7.5%) as compared to 127 (12.4%) with the CP method. This reduction in SBL smears with the TP method and consequent increase in satisfactory smears were highly significant (P < .001) by McNemar's test. As regards unsatisfactory smears in discordant pairs, although the number of unsatisfactory smears was higher with TP (41 cases) as against CP (27 cases), the difference was not statistically significant (P < .05). The split-sample method showed a high correlation between the CP and TP diagnoses. TP smears had a significant advantage over CP smears in the reduction in the number of ASCUS and AGUS cases (14 vs. 29) (P < .05) and increased the pickup rate of LSIL, 6 vs. 1. Time taken to screen the TP smears was half that of CP smears. No cases of LSIL or HSIL were missed on TP smears. CONCLUSION: The liquid-based processor significantly improved the adequacy and quality of smears, resulting in fewer recall cases for SBL smears, leading to more definitive diagnoses in atypical cases, increasing the pickup rate of LSILs and reducing the screening time. A machine handling multiple specimens automatically would decrease cost and be an asset to a cytopathology laboratory. 相似文献