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91.
Relatively nonmyelotoxic drugs and drug combinations were investigated for their ability to eliminate malignant cells from human bone marrow. In vitro 90% inhibitory concentration (IC90) doses were established on granulocyte macrophage colony-forming units (GM-CFU) in culture of bone marrow by using the GM-CFU assay for the following drugs: 4- hydroperoxycyclophosphamide (4-HC), Adriamycin, L-asparaginase, bleomycin, hydrocortisone, VP-16, spirogermanium, Taxol, and vincristine. The leukemic cell kill efficiency of these drugs at IC90 doses was compared with that of 4-HC on acute lymphoid leukemia (ALL) cell lines by using the limiting-dilution assay. Under these conditions, no single drug was superior to 4-HC. To increase the in vitro effect in leukemic cell kill, combinations of vincristine with hydrocortisone, Adriamycin, VP-16, and 4-HC were investigated. Vincristine at 1 to 5 micrograms/mL increased the marrow cytotoxicity of hydrocortisone, Adriamycin, and VP-16, but it was protective (subadditive) with 4-HC. Vincristine and 4-HC in combination was additive to supraadditive on ALL cell lines, increased the leukemic cell kill by one to two logs above 4-HC alone at IC90 doses (P less than .05), and was not affected by the addition of excess marrow cells. The recommended doses for chemopurging in clinical studies are vincristine, 1 to 5 micrograms/mL, plus 4-HC, 5 micrograms/mL.  相似文献   
92.
Little information is available about the potential role of brain (type B) natriuretic peptide in patients with acute myocardial infarction. We therefore analyzed peptide levels, measured at discharge from our coronary care unit, in 56 patients admitted with a diagnosis of acute myocardial infarction. We examined peptide concentrations in the light of different features in our patients, and found a significant association between natriuretic peptide levels and the two most important prognostic factors: left ventricular ejection fraction, and the severity and extent of coronary disease. Type B natriuretic peptide was a good predictor of these features, and we conclude that concentration of type B natriuretic peptide, measured at discharge from the coronary care unit, provides important clinical and prognostic information in patients with acute myocardial infarction.  相似文献   
93.
The pump's outflow connector of the Novel Left Ventricular Assist System I (Novel LVAS I) has been redesigned to be sutured to the infrarenal abdominal aorta either as a procedure of choice (due to its simplicity) or as an alternative in the presence of an unhealthy descending thoracic aorta. The implantation of the Novel Left Ventricular Assist System II (Novel LVAS II) requires only a single passage of the pump's inflow connector through the diaphragm. Of still greater importance, the Novel LVAS II enables a considerably shorter (20- or 22-mm) Dacron vascular graft as the outflow connector to the abdominal infrarenal aorta. The electrocardiogram-synchronized Novel LVAS II possibly ensures the most effective approach to the perfusion of visceral organs and kidneys, while avoiding both excessive mechanical stress on the blood and anatomical and functional damage to the native left ventricle.  相似文献   
94.

Objective

To provide practical recommendations for the evaluation and treatment of metabolic bone disease in human immunodeficiency virus (HIV) patients.

Participants

Members of scientific societies related to bone metabolism and HIV: Grupo de Estudio de Sida (GeSIDA), Sociedad Española de Endocrinología y Nutrición (SEEN), Sociedad Española de Investigación Ósea y del Metabolismo Mineral (SEIOMM), and Sociedad Española de Fractura Osteoporótica (SEFRAOS).

Methods

A systematic search was carried out in PubMed, and papers in English and Spanish with a publication date before 28 May 2013 were included. Recommendations were formulated according to GRADE system (Grading of Recommendations, Assessment, Development, and Evaluation) setting both their strength and the quality of supporting evidence. Working groups were established for each major part, and the final resulting document was later discussed in a face-to-face meeting. All the authors reviewed the final written document and agreed with its content.

Conclusions

The document provides evidence-based practical recommendations on the detection and treatment of bone disease in HIV-infected patients.  相似文献   
95.
The epoxidation reaction of R-carvone 8 with peracetic acid 9 has been studied within the molecular electron density theory at the B3LYP/6-311(d,p) computational level. The chemo- and stereoisomeric reaction paths involving the two C–C double bonds of R-carvone 8 have been studied. DFT calculations account for the high chemoselectivity involving the C–C double bond of the isopropenyl group and the low diastereoselectivity, in complete agreement with the experimental outcomes. The Baeyer–Villiger reaction involving the carbonyl group of R-carvone 8 has also been analysed. A bonding evolution theory analysis of the epoxidation reaction shows the complexity of the bonding changes taking place along this reaction. Formation of the oxirane ring takes place asynchronously at the end of the reaction by attack of anionic oxygen on the two carbons of the isopropenyl C–C double bond.

The epoxidation reaction of R-carvone 8 with peracetic acid 9 has been studied within the molecular electron density theory at the B3LYP/6-311(d,p) computational level.  相似文献   
96.
97.
This study evaluated the safety and efficacy of a sirolimus, corticosteroid, and cyclosporine reduction regimen in an open‐label, 12‐month trial of 420 de novo renal allograft recipients at 49 European transplant centers. One month post‐transplantation, 357 patients were randomized to receive standard‐dose cyclosporine (sCsA, n = 179) or reduced‐dose cyclosporine (rCsA, n = 178). All patients also received sirolimus and corticosteroids. The primary end points were the rate of biopsy‐confirmed acute rejection (BCAR) and renal function, as measured by serum creatinine. Baseline demographic and donor characteristics were similar between groups. BCAR rates at 12 months were not significantly different: 11.2% for rCsA patients and 16.2% for sCsA patients. Mean serum creatinine (±SEM) was significantly lower (1.75 ± 0.10 vs. 1.97 ± 0.07 mg/dl, < 0.001), and creatinine clearance (±SEM; Nankivell method) was significantly higher (57.8 ± 1.78 vs. 49.5 ± 2.46 ml/min, < 0.001) in patients receiving rCsA versus sCsA at 1 year, respectively. Patient and graft survival exceeded 98% in both groups. No significant differences in infection or malignancy were noted between groups. The rCsA with sirolimus and corticosteroid regimen resulted in excellent 12‐month patient and graft survival, a low incidence of BCAR, and improved renal function in renal allograft recipients. Sirolimus administered with rCsA and corticosteroids provided adequate immunosuppression while reducing the potential for the nephrotoxic effects of cyclosporine. These findings may help to improve long‐term renal allograft outcomes.  相似文献   
98.
Transplant recipients receiving immunosuppressive therapy are at increased risk of active cytomegalovirus (CMV) infection and disease. Without appropriate prophylaxis, as many as 80% of solid organ transplant recipients may experience CMV infection. In addition to the direct effects of CMV, infection may be associated with a range of indirect effects, including an increase in risk of other infections, as well as a higher incidence of rejection, graft loss and death. The indirect effects of CMV infection can vary depending on the transplanted organ. For example, CMV-infected kidney transplant recipients may be at increased risk of cardiovascular disease and diabetes, while CMV infection in liver transplant recipients may potentiate hepatitis C infection and increase the risk of post-transplant lymphoproliferative disease. Indirect effects result from a number of pathological processes, including immune modulation and immunosuppression, generation of cytotoxic, pro-inflammatory responses, and smooth muscle proliferation. Prophylactic treatment with antiviral medication can reduce the risk of CMV disease, thereby improving graft survival and overall outcomes, particularly in kidney and heart transplant recipients. Antiviral prophylaxis should be considered for all patients at risk of CMV infection after solid organ transplantation. In this paper we review the main indirect effects of CMV infection in solid organ transplant recipients, and the impact of CMV prophylaxis on these effects.  相似文献   
99.
100.
A new series of oligomethylene bis(nitrophenylureylbenzamide) receptors were synthesized varying the relative position of the urea and amide groups (ortho4 and meta8) and the length of the oligomethylene chain (C2 to C8). An anion recognition study was performed with TBAX salts (X = AcO, BzO, F, H2PO4, and HP2O73−) by UV-vis and 1H NMR. The flexibility of these receptors allows a cooperative effect of both ureylbenzamide units in the receptors. Noteworthy, the ortho position favored the 1 : 1 stoichiometry in the complexes with the carboxylates. The formation of 2 : 1 receptor–anion complexes with both types of receptors 4 and 8 and with hydrogen pyrophosphate and high log K values obtained were very significant in this work. The NMR studies evidenced the formation of supramolecular complexes, even in a competitive solvent, such as DMSO.

Synthesis and supramolecular interaction of new oligomethylene bis(4-nitrophenylureylbenzamide) receptors with different anions.  相似文献   
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