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1.
Little is known about Mg induced Ca deficiency in alkaline conditions, and the relationship between Mg induced Ca deficiency and Na induced Ca deficiency. Dilute nutrient solutions (dominated by Mg) were used to investigate the effect of Ca activity ratio (CAR) on the growth of mungbeans (Vigna radiata (L.) Wilczek cv. Emerald). At pH 9.0, root growth was reduced below a critical CAR of 0.050 (corresponding to 90% relative root length). Root growth was found to be limited more in Mg solutions than had been previously observed for Na solutions. Using a CAR equation modified with plasma membrane binding constants (to incorporate the differing antagonistic effects of Mg and Na), new critical CAR values were calculated for both Na (0.56) and Mg (0.44) dominated solutions. This modified CAR equation permits the calculation of CAR irrespective of the dominant salt present.  相似文献   
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M. Albert Menzies 《CMAJ》1965,93(14):743-747
Various forms of collaboration between the disciplines of public health and psychiatry are briefly reviewed and the 25-year-old mental health program of the Vancouver Health Department is described. The public health nurse has prime responsibility in all children with emotional disorders. She is supported by a psychiatric team which provides active treatment and educational and consultative help for the nurse and the school. During the year 1963, six social workers had 2357 contacts with nurses and school personnel but only 1049 treatment interviews. Of 401 children referred to the psychiatric team, 138 received active clinic treatment, 141 remained under supervision by the public health nurse, and 122 were referred elsewhere. In addition, 1330 children were identified as “mental hygiene cases” in the caseload of the 170 public health nurses in the community. By close co-ordination, the public health nurse and the psychiatric team can enhance each other''s contributions to community mental health.  相似文献   
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The combination of ipilimumab and nivolumab is a highly active systemic therapy for metastatic melanoma but can cause significant toxicity. We explore the safety and efficacy of this treatment in routine clinical practice, particularly in the setting of serine/threonine‐protein kinase B‐Raf (BRAF)‐targeted therapy. Consecutive patients with unresectable stage IIIC/IV melanoma commenced on ipilimumab and nivolumab across 10 tertiary melanoma institutions in Australia were identified retrospectively. Data collected included demographics, response and survival outcomes. A total of 152 patients were included for analysis, 39% were treatment‐naïve and 22% failed first‐line BRAF/MEK inhibitors. Treatment‐related adverse events occurred in 67% of patients, grade 3–5 in 38%. The overall objective response rate was 41%, 57% in treatment‐naïve and 21% in BRAF/MEK failure patients. Median progression‐free survival was 4.0 months (95% CI, 3.0–6.0) in the whole cohort, 11.0 months (95% CI, 6.0‐NR) in treatment‐naïve and 2.0 months (95% CI, 1.4–4.6) in BRAF/MEK failure patients. The combination of ipilimumab and nivolumab can be used safely and effectively in a real‐world population. While first‐line efficacy appears comparable to trial populations, BRAF‐mutant patients failing prior BRAF/MEK inhibitors show less response.  相似文献   
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Background

Latent tuberculosis infection (LTBI) is a reservoir for new TB cases. Isoniazid preventive therapy (IPT) reduces the risk of active TB by as much as 90%, but LTBI screening has limitations. Unlike tuberculin skin testing (TST), interferon-gamma release assays are not affected by BCG vaccination, and have been reported to be cost-effective in low-burden countries. The goal of this study was to perform a cost-effectiveness analysis from the health system perspective, comparing three strategies for LTBI diagnosis in TB contacts: tuberculin skin testing (TST), QuantiFERON®-TB Gold-in-Tube (QFT-GIT) and TST confirmed by QFT-GIT if positive (TST/QFT-GIT) in Brazil, a middle-income, high-burden country with universal BCG coverage.

Methodology/Principal Findings

Costs for LTBI diagnosis and treatment of a hypothetical cohort of 1,000 adult immunocompetent close contacts were considered. The effectiveness measure employed was the number of averted TB cases in two years. Health system costs were US$ 105,096 for TST, US$ 121,054 for QFT-GIT and US$ 101,948 for TST/QFT-GIT; these strategies averted 6.56, 6.63 and 4.59 TB cases, respectively. The most cost-effective strategy was TST (US$ 16,021/averted case). The incremental cost-effectiveness ratio was US$ 227,977/averted TB case for QFT-GIT. TST/QFT-GIT was dominated.

Conclusions

Unlike previous studies, TST was the most cost-effective strategy for averting new TB cases in the short term. QFT-GIT would be more cost-effective if its costs could be reduced to US$ 26.95, considering a TST specificity of 59% and US$ 18 considering a more realistic TST specificity of 80%. Nevertheless, with TST, 207.4 additional people per 1,000 will be prescribed IPT compared with QFT.  相似文献   
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The phytotoxicity of Mn is important globally due to its increased solubility in acid or waterlogged soils. Short‐term (≤24 h) solution culture studies with 150 µM Mn were conducted to investigate the in situ distribution and speciation of Mn in apical tissues of hydrated roots of cowpea [Vigna unguiculata (L.) Walp. cv. Red Caloona] using synchrotron‐based techniques. Accumulation of Mn was rapid; exposure to 150 µM Mn for only 5 min resulting in substantial Mn accumulation in the root cap and associated mucigel. The highest tissue concentrations of Mn were in the root cap, with linear combination fitting of the data suggesting that ≥80% of this Mn(II) was associated with citrate. Interestingly, although the primary site of Mn toxicity is typically the shoots, concentrations of Mn in the stele of the root were not noticeably higher than in the surrounding cortical tissues in the short‐term (≤24 h). The data provided here from the in situ analyses of hydrated roots exposed to excess Mn are, to our knowledge, the first of this type to be reported for Mn and provide important information regarding plant responses to high Mn in the rooting environment.  相似文献   
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Irisin was first identified in muscle cells. We detected irisin immunoreactivity in various organs of the crested porcupine (Hystrix cristata). In the epidermis, irisin immunoreactivity was localized mainly in stratum basale, stratum spinosum and stratum granulosum layers; immunoreactivity was not observed in the stratum corneum. In the dermis, irisin was found in the external and internal root sheath, cortex and medulla of hair follicles, and in sebaceous glands. Irisin immunoreactivity was found in the neural retina and skeletal muscle fibers associated with the eye. The pineal and thyroid glands also exhibited irisin immunoreactivity.  相似文献   
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