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1.
《Saudi Journal of Biological Sciences》2022,29(12):103450
BackgroundBlood product supply and utilization are understudied in Saudi Arabia. This study evaluates the trends in Saudi blood banks readiness, donors’ demography, and blood product utilization and wastage.Study design and methodsA retrospective, cross-sectional study of records obtained from the Ministry of Health (MOH) was initiated to report trends and statistics on annual whole blood donors and blood product utility from 2010 to 2020. Data collected in 2020 was further characterized for donors’ demographics, laboratory readiness, and staffing.ResultsThe average number of annual blood donors over the last decade (2010–2020) was 325,847.3 ± 43,160. The forecasted blood donation and dispatch trends suggest a significant increase in blood demand (R2 = 0.7582) over annual donation rates (R2 = 0.2356). In 2020, 342,460 nationwide blood donations were registered in governmental donation centers and females constituted a mere 2.5 %. Approximately 60 % of whole blood donation was voluntary, 36% was compensatory, and 4% was part of driving license renewal. The highest blood donation rate per 1,000 inhabitants was observed in Taif (69.8) and Alqonfoda (45.0). Eastern directory and Madinah had the most successful donation campaigns attracting 53% and 50% of total annual donations, respectively. Notably, Tabouk, Hai’l, and Albaha had the highest blood product wastage medians.ConclusionBlood donation rates and impetus, staffing ratios, and laboratory readiness and wastage varied among the various directories. Laboratory managers and medical directors need to increase efforts to refine current guidelines in order to comply with the transformation plan of the health sector. 相似文献
2.
J. L. Wilkens T. Kuramoto 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1998,168(7):483-490
The decapod cardiovascular system consists of a single ventricle that pumps blood into seven arteries; previous work has
shown that the outflow distribution patterns of intact animals are variable. In the present study, flow recordings were made
from pairs of arteries in semi-isolated hearts whilst different cardioactive hormones were infused into the heart. Each hormone
(5-hydroxytryptamine, octopamine, dopamine, proctolin and F1) changed the outflow pattern, heart rate and ventricular pressure
in a unique way. The probable sites of hormone action are the cardioarterial valves located at the origin of each artery except
one, the dorsal abdominal. Outflow from the dorsal abdominal is controlled downstream by valves located at the origin of the
segmental lateral arteries. The responses to a particular hormone were sometimes different between the hearts of American
and Japanese lobsters.
Accepted: 11 May 1998 相似文献
3.
Jerry W. McClure 《Phytochemistry》1974,13(7):1065-1069
Five-day-old etiolated barley shoots respond to brief illumination with red light by increasing their level of PAL ca 50% within 5 hr. When assayed s 相似文献
4.
To evaluate blood lead levels (BLLs) and possible influencing factors among children and adolescents in Lu’an, we collected blood samples of 3266 outpatients aged 1–18 years from January 2012 to December 2014 and BLLs were determined by atomizer absorption spectrophotometer. The results showed that the geometric mean (GM) of BLLs was 29.53 μg/L (95% CI: 29.00–30.06 μg/L) and the prevalence of BLLs ≥50 and 100 μg/L were 17.7% and 0.2%, respectively. The GM BLLs and prevalence of BLLs ≥50 μg/L were increased with age before 7 years old and then slightly decreased, and, contrary to previous studies, they were the highest at Jan–Feb and the lowest at Sep–Oct. From 2012 to 2014, the GM BLLs were significantly increased (P < 0.001) while the prevalence of BLLs ≥50 μg/L was decreased but with no significant difference (P > 0.05). These results suggested that although the BLLs of Lu’an children were lower than most areas of China and several neighboring cities as previously reported, they were still higher than that of developed countries. Meanwhile, the GM BLLs of children and adolescents from Lu’an have a trend of increase in recent years. A lot of future works need to be done to identify the risk factors for lead exposure. 相似文献
5.
Peter W. Wilson Katie E. Osterday Aaron F. Heneghan Anthony D. J. Haymet 《The Journal of biological chemistry》2010,285(45):34741-34745
In this study, we examined the effects that antifreeze proteins have on the supercooling and ice-nucleating abilities of aqueous solutions. Very little information on such nucleation currently exists. Using an automated lag time apparatus and a new analysis, we show several dilution series of Type I antifreeze proteins. Our results indicate that, above a concentration of ∼8 mg/ml, ice nucleation is enhanced rather than hindered. We discuss this unexpected result and present a new hypothesis outlining three components of polar fish blood that we believe affect its solution properties in certain situations. 相似文献
6.
The shikimate/arogenate pathway: Link between carbohydrate metabolism and secondary metabolism 总被引:2,自引:0,他引:2
Roy A. Jensen 《Physiologia plantarum》1986,66(1):164-168
7.
We investigated the synthesis and translocation of amino compounds in Parasponia, a genus of the Ulmaceae that represents the only non-legumes known to form a root nodule symbiosis with rhizohia. In the xylem sap of P. andersonii we identified asparagine. aspartate. glutamine, glutamated significant quantities of a non-protein amino acid. 4-methylglutamte(2-amino-4-methylpentanedioic acid). This identification was confirmed by two methods, capillary gas chromatography (GC) electron ionization (El) mass spectrometry (MS) and reverse phase high pressure liquid chromatography (HPLC) analysis of derivatized compounds. In leaf, root and nodule samples from P. andersonii and P. parviflora we also identified the related compounds 4-methyleneglutamate and 4-methyleneglulamine. Using 15N2 labelling and GC-Ms analysis of root nodule extracts we followed N2 fixation and ammonia assimilation in P. andersonii root nodules and observed Label initially in glutamine and subsequently in glutamate, suggesting operation of the glutamine synthetase/glutamine:2-oxoglutarate aminotransferase (GS/GOGAT) pathway. Importantly, we observed the incorporation of significant quantities of 15N into 4-methylglutamate in nodules, demonstrating the de nova synthesis of this non protein amino acid and suggesting a role in the translation of N in symbioticParasponia. 相似文献
8.
John W. Wright Anita J. Bechtholt Shelley L. Chambers Joseph W. Harding 《Peptides》1996,17(8):1365-1371
The present investigation determined that native angiotensins II and III (ANG II and III) were equipotent as pressor agents when ICV infused in alert rats, whereas native angiotensin IV (ANG IV) was less potent. An analogue of each of these angiotensins was prepared with a hydroxyethylamine (HEA) amide bond replacement at the N-terminus, yielding additional resistance to degradation. These three angiotensin analogues, HEA-ANG II, HEA-ANG III, and HEA-ANG IV, were equivalent with respect to maximum elevation in pressor responses when ICV infused; and each evidenced significantly extended durations of effect compared with their respective native angiotensin. Comparing analogues, HEA-ANG II had a significantly longer effect compared with HEA-ANG III, and HEA-ANG IV, whereas the latter were equivalent. Pretreatment with the AT1 receptor subtype antagonist, Losartan (DuP753), blocked subsequent pressor responses to each of these analogues, suggesting that these responses were mediated by the AT1 receptor subtype. Pretreatment with the specific AT4 receptor subtype antagonist, Divalinal (HED 1291), failed to influence pressor responses induced by the subsequent infusion of these analogues. These results suggest an important role for Ang III, and perhaps ANG IV, in brain angiotensin pressor responses mediated by the AT1 receptor subtype. 相似文献
9.
BackgroundTrace elements are important factors in human reproductive health. Among them, special attention is paid to zinc, which is an essential trace element and is necessary for the normal functioning of the male reproductive system and the process of spermatogenesis. The aim of the study was to investigate the association between seminal and serum zinc concentrations and semen quality and reproductive hormone levels in population of Russian young men.MethodsThe study population consisted of 626 young Russian men (median age 22.5 years), recruited from the general population, regardless of their fertility status. Each participant provided semen and blood sample, information about his lifestyle and ethnicity. Semen quality (sperm concentration, motility and morphology), reproductive hormone levels (testosterone, estradiol, LH, FSH and inhibin B), and serum and seminal zinc concentrations were evaluated. The semen samples were analyzed according to the WHO laboratory manual (WHO, 2010). Serum hormones were measured by enzyme immunoassay, zinc concentrations were determined using spectrophotometry and direct colorimetry without deproteinization.ResultsZinc was present in the seminal plasma in a significantly higher concentration than in the blood serum (median serum Zn concentration was 23.6 μmol/L vs seminal Zn concentration 1571.8 μmol/L). The seminal zinc concentration was positively related to the total sperm count, sperm concentration, progressive motility and normal morphology (Spearman’s test: 0.221; 0.286; 0.269; 0.183, respectively, p < 0.001), while the serum Zn concentration was negatively related to serum testosterone and estradiol levels (r = −0.249 and r = −0.096, respectively, p < 0.001−0.05). It was found that the seminal Zn content in men with normal semen quality was higher compared to men with lowered semen quality (means: 6.37 and 5.03 μmol/ejaculate, respectively, p < 0.001). Similarly, the semen volume, total sperm count, sperm concentration, progressive motility, normal morphology and the serum testosterone level in men with the seminal Zn deficiency were lower than in men with the normal seminal Zn content.ConclusionBased on the results of our population-based study, seminal Zn levels were closely associated with semen parameters in young men, so Zn deficiency may be an important risk factor for lowered semen quality. Seminal Zn determinations should be considered as a useful tool in addition to other parameters in assessing male fertility. 相似文献
10.
Huntington’ disease (HD) is an autosomal dominant neurodegenerative disease characterized by progressive motor, psychiatric, and cognitive deterioration. HD is, together with spinocerebellar ataxias, spinobulbar muscular atrophy and dentatorubral-pallido- luysian atrophy, one of the nine disorders caused by an expansion of glutamine residues in the causative protein where the polyglutamine expansion cause aberrant protein folding. Since an excessive metal’s accumulation in organs may induce protein misfolding and oxidative stress, we have studied the blood concentration of essential (Cr, Co, Cu, Fe, Mn, Mo, Ni, Se, Zn) and nonessential (As, Cd, Sb, Sn, V) trace elements in HD patients.We found increased levels of the essential elements iron, chromium, selenium and zinc and of the nonessential element arsenic in the blood of HD patients.Since alteration in metals homeostasis may contribute to the pathogenesis of neurodegenerative disease and could eventually constitute a target for therapy, we may suggest the utilize of the blood metal profile as a further in vivo tool to study and characterize Huntington disease. 相似文献