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1.
In order to satisfy the energy demands of the electromobility market, further improvements in cathode materials are receiving much attention, especially high energy density cathode materials for Li-ion batteries (LIBs). In this work, the self-propagating combustion (SPC) method is use to synthesise undoped LiNi0.6Co0.3Ti0.1O2 (LNCT), novel nano-sized Al-doped LiNi0.6Co0.3−xAlxTi0.1O2 (LCA) and LiNi0.6−xCo0.3AlxTi0.1O2 (LNA) (x = 0.01) cathode materials. LNCT, LCA and LNA were annealed at 700 °C for 24 h. Following the synthesis, the phase, chemical structure and purity of the materials were analysed using X-ray diffraction (XRD). Based on the XRD results, all materials exhibit a single-phase structure with rhombohedral layered structure. Based on the HRTEM and EDX results, all samples exhibit polyhedral-like shapes, while the Al-doped samples display smaller crystallite sizes compared to the undoped sample. As for the electrochemical performances, the initially discharged capacity of LCA (238.6 mA h g−1) is higher than that of LNA (214.7 mA h g−1) and LNCT (150.5 mA h g−1). However, LNA has a lower loss of capacity after the 50th cycle compared to the LCA sample, which makes it a more excellent candidate for electrochemical applications. The main reason for the excellent electrochemical behaviour of LNA is due to lower cation mixing. Furthermore, Rietveld refinements reveal that the LNA sample has a longer atomic distance of Li–O and shorter TM–O in the cathode structure, which makes Li+ ion diffusion more efficient, leading to excellent electrochemical performance. These findings further proved the potential of the novel nano cathode material of LiNi0.6−xCo0.3AlxTi0.1O2 (LNA) to replace the existing commercialized cathode materials for rechargeable Li-ion batteries.

Al substitute into Ni site increase Li–O and reduce M–O atomic distance lead to excellent cycleability with high energy density.  相似文献   
2.
Primary hyperaldosteronism, one cause of which is aldosterone-producing adenomas (APAs), may account for ≤5% to 10% of cases of essential hypertension. Germline mutations have been identified in 2 rare familial forms of primary hyperaldosteronism, but it has been reported recently that somatic mutations of the KCNJ5 gene, which encodes a potassium channel, are present in some sporadic nonsyndromic APAs. To address this further we screened 2 large collections of sporadic APAs from the United Kingdom and Australia (totalling 73) and found somatic mutations in the selectivity filter of KCNJ5 in 41% (95% CI: 31% to 53%) of the APAs (30 of 73). These included the previously noted nonsynonymous mutations, G151R and L158R, and an unreported 3-base deletion, delI157, in the region of the selectivity filter. APAs containing a somatic KCNJ5 mutation were significantly larger than those without (1.61 cm [95% CI: 1.39-1.83 cm] versus 1.04 cm [95% CI: 0.91-1.17 cm]; P<0.0001) but with substantial overlap in size between genotypes. The APAs carrying a mutation, but not those without, also consistently lacked a postural aldosterone response, suggesting a physiologically distinct subtype. Hence, somatic KCNJ5 mutations are not restricted to large APAs (>2 cm), and their frequency in our unselected series suggests they are common and could be important in the molecular pathogenesis of many sporadic cases of APA.  相似文献   
3.
Antigen challenge of isolated perfused kidneys of sensitized guinea-pigs consistently released a large proportion of their histamine content, and caused a reduction in renal perfusate flow rate (RPFR) which could not simply be due to the released histamine, since much larger amounts of exogenous histamine were needed to produce a comparable effect. Reduction in RPFR by histamine was blocked by mepyramine but not by cimetidine, i.e. it is mediated by an H1-receptor mechanism.  相似文献   
4.
Pyoderma gangrenosum (PG) is an uncommon, chronic, painful, ulcerative skin disease of unknown origin, often associated with systemic diseases including inflammatory bowel disease, rheumatoid arthritis; monoclonal gammopathy, hepatitis and myeloproliferative disorders. The mainstay of therapy for PG has been high-dose corticosteroids but not all patients have a favourable outcome. Other systemic agents have also been used such as cyclosporine, azathioprine, cyclophosphamide and tacrolimus. However, all these systemic therapies can be complicated by serious side effects. In this paper, we report a series of four patients with pyoderma gangrenosum treated successfully with topical cyclosporine. No side-effects were observed in any of the patients and there was minimal systemic absorption of the topical cyclosporine.  相似文献   
5.
ABSTRACT: BACKGROUND: The role of dietary factors in the pathophysiology of acne vulgaris is highly controversial. Hence, the aim of this study was to determine the association between dietary factors and acne vulgaris among Malaysian young adults. METHODS: A case-control study was conducted among 44 acne vulgaris patients and 44 controls aged 18 to 30 years from October 2010 to January 2011. Comprehensive acne severity scale (CASS) was used to determine acne severity. A questionnaire comprising items enquiring into the respondent's family history and dietary patterns was distributed. The subjects were asked to record their food intake on two weekdays and one day on a weekend in a three day food diary. Anthropometric measurements including body weight, height and body fat percentage were taken. Acne severity was assessed by a dermatologist. RESULTS: Cases had a significantly higher dietary glycemic load (175 +/- 35) compared to controls (122 +/- 28) (p < 0.001). The frequency of milk (p < 0.01) and ice-cream (p < 0.01) consumptions was significantly higher in cases compared to controls. Females in the case group had a higher daily energy intake compared to their counterparts in the control group, 1812 +/- 331 and 1590 +/- 148 kcal respectively (p < 0.05). No significant difference was found in other nutrient intakes, Body Mass Index, and body fat percentage between case and control groups (p > 0.05). CONCLUSIONS: Glycemic load of diet and frequencies of milk and ice cream intake were positively associated with acne vulgaris.  相似文献   
6.
This study evaluated implementing a school-based intervention to promote healthier dietary habits in the school environment among Malaysian adolescents using qualitative methods. This qualitative study was conducted in four secondary schools in Perak and Selangor (two urban and two rural schools) that received the intervention (either training or training and food subsidy). A total of eight focus groups (68 students aged 15 years old) and 16 in-depth interviews were conducted with canteen operators, school convenience shop operators, school teachers and school principals in each school. Thematic analysis was used to analyse the qualitative data to identify suitable themes. We found several initiatives and changes by the schools’ stakeholders to change to a healthy school canteen programme. The stakeholders also noticed the students’ food preferences that influence healthy food intake in canteens and convenience shops. The food vendors and school administrators also found that subsidising healthy meals might encourage healthy eating. Among barriers to implementing healthy school initiatives were the student’s perception of healthy food and their eating habits, which also affect the food vendors’ profit if they want to implement a healthy canteen. The school-based intervention has the potential to promotes healthier eating among school adolescents. Continuous training and monitoring of canteen operators and convenience shops are needed, including building partnerships and educating the students on healthy eating to cultivate healthy eating habits.  相似文献   
7.
8.
The pathogenesis of cisplatin-induced renal failure is related to reduced renal blood flow due to severe tubular damage and enhanced renovascular resistance. It is also known that alpha(1)-adrenoceptors, the major subtype of alpha-adrenoceptors in renal vasculature play the pivotal role in regulating renal hemodynamics. With this background, we have hypothesized that the altered renal hemodynamics and enhanced renovascular resistance in cisplatin-induced renal failure might be caused by the altered alpha-adrenergic responsiveness with a possible involvement of alpha(1)-adrenoceptors in the renal vasculature. In a unique experimental approach with anesthetized rats, this study has therefore examined if there is any shift in the renovascular responsiveness to renal nerve stimulation and a series of alpha-adrenergic agonists in Wistar Kyoto (WKY) and spontaneously hypertensive (SHR) rats with cisplatin-induced renal failure in comparison with their body weight-matched normal controls. Thirty-two male rats of both WKY (n=16) and SHR (n=16) origin with body weight 236+/-7.9 g received cisplatin (5mg/kg i.p.). The renal failure was confirmed in terms of significantly reduced renal blood flow, reduced creatinine clearance, increased fractional excretion of sodium, increased kidney index (all P<0.05) and tubular damage. After 7 days of cisplatin, the overnight fasted rats were anesthetized (sodium pentobarbitone, 60 mg/kg i.p.) and renal vasoconstrictor experiments were done. The changes in the vasoconstrictor responses were determined in terms of reductions in renal blood flow caused by electrical renal nerve stimulation or intrarenal administration of noradrenaline, phenylephrine and methoxamine. It was observed that in the cisplatin-treated renal failure WKY and SHR rats there were significant (all P<0.05) reductions in the renal blood flow along with significantly (P<0.05) higher renal adrenergic responsiveness as compared with their non-renal failure controls. The data showed that in the renal failure WKY and SHR rats, the altered renal hemodynamics might be caused by an augmented renal adrenergic responsiveness. The results obtained further led us to suggest that the augmented renal adrenergic responsiveness in the cisplatin-induced renal failure rats were possibly mediated by the alpha(1)-adrenoceptors.  相似文献   
9.
A comparison was made between collagenase-dispersed guinea-pig atrial and ventricular tissues. Heparin containing cells were stained with alcian blue at pH 2.2, and counted by an automated technique (Technicon H6000). The cells were challenged with the specific antigen (ovalbumin), with antisera to guinea-pig IgG (non-subclass specific), IgG1 and IgG2, and the calcium ionophore A23187. Histamine release was measured by an automated spectrofluorometric technique, and leukotriene C4 was measured by radioimmunoassay.All of the following parameters were higher in the atrial than in ventricular cells (mean ratio and SEM of atrial: ventricular mast cell parameters in parenthesis): 1) Histamine content/g wet tissues (3.32±0.71:1) (p<0.05), 2) Absolute mast cell number as a proportion of total cell count (3.75±1.64:1), 3) Histamine release induced by antigen (significant in one out of four experiments), anti-IgG (significant in three out of four experiments), anti-IgG1 (significant in two out of four experiments), and anti-IgG2 (higher but not statistically significant).Ionophore A23187 gave an inconsistent histamine release pattern: significantly higher release from atria in five treatments (different concentrations in different experiments), and higher ventricular release in three.Significantly more leukotriene C4 was released by antigen and the ionophore A23187 (mean of 3–5 treatments), but not with anti-IgG.  相似文献   
10.

Purpose

We tested the accuracy of the diagnosis and the value of each step of the diagnostic process in a group of patients undergoing reinvestigation of interstitial cystitis (IC).

Materials and Methods

A total of 61 patients with a provisional diagnosis of IC underwent systematic reinvestigation by a pathway involving a thorough history and physical examination, a rigorous search for urinary infection, frequency volume records, urodynamics and cystoscopy under general anesthesia. Abnormalities detected in the course of this pathway were treated before proceeding with further investigation.

Results

The diagnosis of IC was confirmed or considered possible in only 34 cases (55%). Common alternative diagnoses included recurrent urinary tract infections, detrusor overactivity and vaginal candidiasis. Of 5 male patients only 1 was confirmed to have IC. The original diagnosis was overturned by history and physical examination (including urine cultures) in 11 cases, by urodynamic investigation in 11 and by cystoscopy in 5.

Conclusions

While IC remains a diagnosis of exclusion, active exclusion of all possible causes of similar symptoms using a thorough investigative algorithm is imperative. Urodynamic investigation, together with a thorough history and physical examination, remains an important component of the diagnostic pathway.  相似文献   
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