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Iron deficiency is a major complication of regular blood donation as a result of regular iron loss from each donated blood unit. Ninety-two regular blood donors and 95 first time blood donors attending a hospital-based blood transfusion centre were assessed as to their haematological and iron status by blood counts and serum ferritin levels as an indicator of iron stores. All donors had passed the haemoglobin-screening test using a copper sulphate method prior to blood donation. Ferritin levels were found to be significantly lower among regular blood donors (47.8 mmol/L) as compared to first time blood donors (94.2 mmol/L). Iron deficiency as observed by low ferritin levels was seen in 7.4% of all first time donors as compared to 17.4% in regular donors. Male first time donors showed a low prevalence of iron deficiency but the prevalence significantly increased with regular blood donation. Female first time and regular blood donors however did not show any significant differences in prevalence of iron deficiency, with both groups exhibiting prevalence rates similar to male regular donors. The association between haemoglobin levels and iron deficiency was poor and the copper sulphate-screening test was found insensitive to anaemia with many donors passing the test and donating blood despite being anaemic. It is concluded that a high prevalence of iron deficiency is present among regular male blood donors and all female donors. Besides, the use of the copper sulphate screening test as a sole criterion for anaemia screening should be reviewed. Ferritin measurements should be included in the routine assessment of blood donors especially among regular blood donors.  相似文献   
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Metal-free organic polymer photocatalysts have attracted dramatic attention in the field of visible light-induced hydrogen evolution reaction (HER). Herein, we showed a polymeric O-linked heptazine polymer (OLHP) decorated with S, N co-doped graphene quantum dots (S,N-GQDs) as a photosensitizer to generate hydrogen upon quantum dot sensitization. Both of these heptazine-based systems show effective photosensitization with strong π–π interactions and enhanced photocatalytic H2 generation (24 times) as metal-free systems. Electrochemical impedance and optical measurements show effective charge transfer kinetics with decreased charge recombination, which is responsible for the enhanced photocatalytic activity. As a result, a significant high apparent quantum yield (AQY) with highest value of 10.2% was obtained for our photocatalyst OLHP/S,N-GQD10.

A polymeric O-linked heptazine polymer (OLHP) decorated with S, N co-doped graphene quantum dots (S,N-GQDs) as a photosensitizer to utilize visible light (λ > 420 nm) for hydrogen generation.  相似文献   
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Background and Objectives Appropriate screening for irregular red‐cell antibodies is essential for ensuring transfusion compatibility and for antenatal management of mothers at risk of haemolytic disease of the foetus and newborn. Screening for all relevant antibodies is, however, limited by screening cells that do not express antigens present in the patient and donor population. Technology to artificially incorporate antigens into red cells is currently available and may be an option for customizing screening cells. Materials and Methods We sought to identify retrospectively the changing patterns of alloantibody prevalence in our multiethnic population on change of screening cells. Antibody screening records of 143 501 patients tested from 2004 to 2010 were retrieved and divided into two groups: period‐1 (2004–2008) and period‐2 (2009–2010). During period‐1, standard screening cells were used while in period‐2, MUT+Mur+ KODE? transformed red cells (kodecytes) were used. Results Four per cent of samples tested during period‐2 were positive on antibody screening compared to 3·2% in period‐1. Specific antibodies, excluding anti‐D, were identified in 1·66% and 1·52% of patients in period‐2 and ‐1, respectively. When confined to antibodies of clinical significance only, period‐2 showed higher alloantibody prevalence of 1·16% as compared to 0·66% in period‐1. Antibodies to glycophorin variants of MNS (vMNS) were more commonly detected while antibodies to Lewis antigens declined during period‐2. Conclusion Antibodies to vMNS antigens are common in South and East Asian populations and are often missed when using standard screening cells. Use of specifically engineered screening cells to express red‐cell antigens artificially is beneficial in detecting the diverse alloantibodies present in our population.  相似文献   
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Prior studies have suggested that intravenous diltiazem reduces the probability of spontaneous conversion of atrial fibrillation (AF) to sinus rhythm in the electrophysiology laboratory and in patients with postoperative AF. Whether diltiazem exerts the same effect in patients presenting to the emergency department (ED) with spontaneous AF is unclear. Fifty patients presenting to the ED with new-onset or paroxysmal AF and a rapid ventricular rate (>100 beats per minute) were randomly assigned to receive intravenous diltiazem or esmolol during the first 24 hours of presentation. Conversion to sinus rhythm occurred in 10 patients (42%) in the diltiazem group compared with 10 patients (39%) in the esmolol group (P = 1.0). Diltiazem does not decrease the likelihood of spontaneous conversion of AF to sinus rhythm in the ED setting.  相似文献   
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Objective

To evaluate the toxicity, predatory efficiency of Delonix elata (D. elata) and Mesocyclops aspericornis (M. aspericornis) against dengue vector, Aedes aegypti (Ae. aegypti).

Methods

A mosquitocidal bioassay was conducted at different concentration of plant extract followed by WHO standard method. The probit analysis of each tested concentration and control were observed by using software SPSS 11 version package. The each tested concentration variable was assessed by DMRT method. The predatory efficiency of copepod was followed by Deo et al., 1988. The predator, M. aspericornis was observed for mortality, abnormalities, survival and swimming activity after 24 h treatment of plant and also predation on the mosquito larvae were observed.

Results

D. elata were tested for biological activity against the larvae, and pupae of Ae. aegypti. Significant mortality effects were observed in each life stage. The percentage of mortality was 100% in first and second instars whereas 96%, 92% in third and fourth instars. Fitted probit-mortality curves for larvae indicated the median and 90% lethal concentrations of D. elata for instars 1-4 to be 4.91 (8.13), 5.16 (8.44), 5.95 (7.76) and 6.87 (11.23), respectively. The results indicate that leaf extract exhibits significant biological activity against life stages. The present study revealed that D. elata is potentially important in the control of Ae. aegypti. Similar studies were conducted for predatory efficiency of Copepod, M. aspericornis against mosquito vector Ae. Aegypti. This study reported that the predatory copepod fed on 39% and 25% in I and III instar larvae of mosquito and in combined treatment of D. elata and copepod maximum control of mosquito larval states and at 83%, 80%, 75% and 53% in I, II, III and IV instars, respectively.

Conclusions

The combined action of plant extract and predatory copepod to effectively control mosquito population and reduce the dengue transmitting diseases.  相似文献   
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Opinion statement Glioblastomas (GBMs) are among the most aggressive of all known human tumors. The median survival times remain in the 12- to 15-month range despite aggressive surgery, radiation, and chemotherapy. Through molecular and genetic profiling efforts, underlying mechanisms of resistance to these therapies are becoming better understood. The present standard of care has been shaped by the recently reported phase III study by the European Organisation for Research and Treatment of Cancer and the National Cancer Institute of Canada, which found that the addition of temozolomide (TMZ) to radiation therapy significantly improved outcome compared with radiation alone. However, careful examination of these data reveals that not all GBM patients benefited from the addition of TMZ to radiation therapy. A companion correlative study found that GBM patients with tumors with MGMT promoter methylation appeared to derive the greatest benefit from the addition of TMZ to radiation therapy. Although this finding is provocative, it should be kept in mind that this study was performed retrospectively and that prospective validation is required before MGMT methylation can be used for clinical stratification purposes. However, this study does show promise for the tailoring of future treatments according to the molecular and genetic profiles of an individual's tumor rather than using the “one-glove-fits-all≓ approach that is currently being followed. As more effective “smart drugs≓ are developed, molecular and genetic profiling will assume even greater importance in this regard.  相似文献   
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