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It was aimed to investigate the compressibility, compactibility, powder flow and tablet disintegration of a new excipient comprising magnesium (Mg) silicate co-processed (5%–85% w/w) onto chitin, microcrystalline cellulose (MCC) and starch as the hydrophilic polymers of interest. Initially, the mechanism of tablet disintegration was studied by measuring water infiltration rate, moisture sorption, swelling capacity and hydration ability. Moreover, the powders compression behavior was carried out by applying Kawakita model of compression analysis in addition to porosity and radial tensile strength measurements. In vitro drug release of compacts made of 400?mg ibuprofen and 300?mg of the hydrophilic polymers containing 30% w/w Mg silicate co-precipitate was investigated in phosphate buffer (pH 7.8). This work demonstrated that the incorporation of Mg silicate to the hydrophilic polymers lead to the improvement of powder flowability, compactibility, stability (with regard to storage conditions), compacts crushing strength, and disintegration time in addition to faster drug release. The overall findings are practically advantageous in the context of finding a low cost and multifunctional co-processed excipient of natural origins.  相似文献   
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Nineteen patients with Fanconi anemia (FA) and bone marrow failure underwent bone marrow transplantation (BMT) from matched siblings. Median age at BMT was 8.7 years. Conditioning consisted of low-dose cyclophosphamide (CY 5 mg/kg x 4 days) and thoracoabdominal irradiation (TAI 400 cGy). Graft-versus-host disease (GVHD) prophylaxis was cyclosporin A (CsA) in 13 patients and CsA plus methotrexate in 6 patients. Antithymocyte globulin (ATG) was added in the pretransplant as well as the post-transplant period. All patients received high-dose acyclovir from day 2 pre-BMT to day 28 post BMT, and intravenous immunoglobulins (IVIG), 500 mg/kg weekly from day 7 pre-BMT to day 90 post BMT. No fungal prophylaxis was given. All patients engrafted, (median, 14 days for an absolute neutrophil count > or =0.5 x 10(9)/l; median, 37 days for platelet count > or =20 x 10(9)/l). Fourteen (74%) patients are alive with sustained engraftment and are transfusion independent. Three (16.6%) patients developed acute GVHD; none developed chronic GVHD. Five (26%) patients developed invasive fungal infections, and two (10%) developed fatal CMV disease. We believe the addition of ATG may have contributed to the increased incidence of severe life-threatening fungal and viral infections in our series.  相似文献   
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Heart transplantation is not yet socially acceptable in the Middle East, and left ventricular assist facilities are not generally available in this region. Therefore, left ventricular volume reduction surgery was attempted in 41 patients with end-stage heart failure (33 males; median age, 36.3 years) in 4 Middle Eastern tertiary referral centers between February 1996 and January 2001. Heart failure was due to idiopathic cardiomyopathy in 21 patients, ischemia in 11, rheumatic valvular disease in 8, and viral myocarditis in 1. Associated procedures were aortic valve replacement in 5 patients, mitral valve repair in 25, mitral valve replacement in 7, tricuspid valve repair in 6, and coronary bypass grafting in 8. Hospital mortality was 31.7%. Five patients were lost to follow-up. The survival rate of hospital survivors at 18 months was 65.2%. Three of the surviving patients did not benefit from the operation. Although our results were somewhat disappointing, this operation remains an option for surgeons working in developing areas of the world. It is hoped that better patient selection and new techniques of left ventricular volume reduction that avoid resection of viable muscle will further improve the outcome of this operation.  相似文献   
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BACKGROUNDThe coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus-2, represents a major challenge to health care systems both globally and regionally, with many opting by cancelling elective surgeries. Cardiac operations in patients diagnosed with COVID-19 have been imperative due to their emergency nature, critical condition of patients awaiting cardiac surgery, and accumulated number of cardiac surgical interventions throughout the last months.CASE SUMMARYHere we describe three COVID-19 positive cases who underwent coronary surgery, on an urgent basis. We did not experience worsening of the patients’ clinical condition due to COVID-19 and therefore a routine post-operative chest X-ray (CXR) was not required. None of the health care providers attending the patients endured cross infection. Further trials would be needed in order to confirm these results.CONCLUSIONWhile the pandemic has adversely hit the health systems worldwide, cardiac surgical patients who concomitantly contracted COVID-19 may undergo a smooth post-operative course as a routine post-operative CXR may not be required.  相似文献   
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Congestive chronic heart failure (CHF) is a progressive disorder in which a complex interaction of haemodynamic, neurohormonal and metabolic disturbances leads to subsequent immune activation. The greatest attention has been given to the concept that the progression of heart failure is due to neurohormonal abnormalities and this has led to substantial therapeutic benefits for CHF. The aim of this review is to describe a number of the interactions between neurohormonal pathways and metabolic problems relevant in CHF. Besides the renin-angiotensin-aldosterone-system, steroid and thyroid hormones, growth factors, insulin and inflammatory cytokines (e.g. tumour necrosis factor-alpha [TNF-alpha]) are considered. TNF-alpha is potentially a key molecule with enormous interactive opportunities within a regulatory network of energy metabolism, immune function and neuroendocrine and hormonal function. The most dramatic metabolic problem in heart failure patients is the development of cardiac cachexia. Currently, no specific therapy exists and the prognosis is poor. There are promising approaches (counteracting TNF-alpha or applying anabolic growth factors) but these are not without risk and are expensive, and their application may, therefore, be limited to certain subgroups of patients. In the future, it will not be enough to monitor cardiac function and symptomatic status in heart failure patients. Rather, the patients' metabolic status may need to be taken, as well as an assessment of peak oxygen consumption, body composition and hormonal status.  相似文献   
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Background

There is still some controversy regarding the ethical issues involved in live donor liver transplantation (LDLT) and there is uncertainty on the range of perioperative morbidity and mortality risks that donors will consider acceptable.

Methods

This study analysed donors’ inclinations towards LDLT using decision analysis techniques based on the probability trade-off (PTO) method. Adult individuals with an emotional or biological relationship with a patient affected by end-stage liver disease were enrolled. Of 122 potential candidates, 100 were included in this study.

Results

The vast majority of participants (93%) supported LDLT. The most important factor influencing participants’ decisions was their wish to improve the recipient''s chance of living a longer life. Participants chose to become donors if the recipient was required to wait longer than a mean ± standard deviation (SD) of 6 ± 5 months for a cadaveric graft, if the mean ± SD probability of survival was at least 46 ± 30% at 1 month and at least 36 ± 29% at 1 year, and if the recipient''s life could be prolonged for a mean ± SD of at least 11 ± 22 months.

Conclusions

Potential donors were risk takers and were willing to donate when given the opportunity. They accepted significant risks, especially if they had a close emotional relationship with the recipient.  相似文献   
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