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71.
72.
In patients undergoing chronic hemodialysis (HD) through an arm arteriovenous fistula (AVF), coronary insufficiency can occur if the patient undergoes a coronary artery bypass graft (CABG) using the ipsilateral internal mammary artery (1-4). Therefore, the creation of a new AVF after CABG should avoid using the arm ipsilateral to the side where the internal thoracic artery was used. In cases where coronary syndrome appears when this advice is not followed, treatment should be offered aimed at overcoming the hemodynamic interference between the diminished coronary supply through the left or right internal mammary artery by closure of the existing fistula, with or without temporary central venous line insertion until the maturation of a new fistula. We suggest a different approach by moving only the arterial inflow site of the AVF to the controlateral subclavian artery, but in addition, leaving the well functioning venous outflow tract intact. In cases of left internal mammary steal it is achieved by creating a conduit running from the right subclavian artery to the left cephalic vein; therefore, creating a new arterial inflow source, connected to the existing functioning old venous outflow tract to maintain an immediately functioning new fistula without a coronary steal.  相似文献   
73.
The modern pharmaceutical industry based on synthetic chemistry severed the historical connection between plants, food and medicines. The growing costs of discovering new chemical entity-based drugs through high throughput screening methods may yet again reconnect plants and human health at a new level of technological sophistication. Multi-component botanical therapeutics that comprise functional foods, dietary supplements and botanical drugs hold several advantages over conventional drugs that may earn them a more prominent place in the medicine of the future. They can deliver mixtures of multi-functional molecules with potentiating and synergistic effects and pleiotropic targeting at a reasonable cost and with fewer regulatory constraints. They are well suited for long-term disease prevention in an era of genetic testing and increased life expectancy. They also provide additional vehicles for delivering health and wellness. Technologies that address the needs of discovery, development and manufacturing of multi-component botanical therapeutics are emerging. They include computational and bioinformatics approaches, cell based gene expression and high-content screening systems, and phytochemical elicitation and unique plant cultivation / extraction methods designed to optimize the production of bioactives, standardize overall extract composition and assure batch-to-batch product consistency. Nevertheless, multi-component botanical therapeutics carry risks associated with potential interactions with conventional drugs and adverse reactions, which are difficult to detect and diagnose. They face problems of acceptance by the medical community and pharmaceutical industry, safety and efficacy validation, poor standardization and quality control, and difficulties in identifying active ingredients and determining their complex mode(s) of action. Solving these problems will accelerate the merger of grocery stores with pharmacies and agriculture with chemical manufacturing and provide physicians and patients with broader and more individualized choices for disease prevention and treatment.  相似文献   
74.
Several recent studies, albeit limited in sample number, design and generalizability, have suggested that augmentation of atypical antipsychotic medication (such as clozapine and olanzapine) with sulpiride, a substituted benzamide antipsychotic medication, may play a role in the management of treatment-resistant psychotic conditions. The objective of this study was to investigate any change in clinical symptomatology or side-effect profile in treatment-resistant schizophrenia patients receiving sulpiride in addition to olanzapine. Seventeen patients with treatment-resistant chronic schizophrenia, who were receiving olanzapine monotherapy for at least 6 months before study commencement, were randomized in a 1:1 fashion to receive either adjunctive treatment with sulpiride (study group) or to continue their pre-study treatment with olanzapine with no medication augmentation (control group), each for a period of 8 weeks. Changes in measures of positive and negative symptoms, anxiety, depression and extrapyramidal symptoms were assessed at baseline and at 8 weeks. Study observations indicated no significant differences in the changes in positive or negative symptomatology between patients receiving a combined regimen of olanzapine with sulpiride (600 mg/ day) augmentation and controls. However, a significantly greater improvement of depressive symptomatology (P < 0.05; as assessed by the Hamilton Scale for Depression) was noted in the sulpiride augmentation group. These data indicate improvement in depressive symptomatology with sulpiride augmentation of olanzapine in treatment-resistant chronic schizophrenia patients.  相似文献   
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The Galerkin truncated inviscid Burgers equation has recently been shown by the authors to be a simple model with many degrees of freedom, with many statistical properties similar to those occurring in dynamical systems relevant to the atmosphere. These properties include long time-correlated, large-scale modes of low frequency variability and short time-correlated "weather modes" at smaller scales. The correlation scaling in the model extends over several decades and may be explained by a simple theory. Here a thorough analysis of the nature of predictability in the idealized system is developed by using a theoretical framework developed by R.K. This analysis is based on a relative entropy functional that has been shown elsewhere by one of the authors to measure the utility of statistical predictions precisely. The analysis is facilitated by the fact that most relevant probability distributions are approximately Gaussian if the initial conditions are assumed to be so. Rather surprisingly this holds for both the equilibrium (climatological) and nonequilibrium (prediction) distributions. We find that in most cases the absolute difference in the first moments of these two distributions (the "signal" component) is the main determinant of predictive utility variations. Contrary to conventional belief in the ensemble prediction area, the dispersion of prediction ensembles is generally of secondary importance in accounting for variations in utility associated with different initial conditions. This conclusion has potentially important implications for practical weather prediction, where traditionally most attention has focused on dispersion and its variability.  相似文献   
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Malignant lymphoma is a heterogeneous disease with different clinical features. Among diffuse large B-cell lymphomas (DLBCLs), a unique subtype has been identified recently based on cell surface marker CD5 and clinicopathological features. These de novo CD5(+) DLBCLs account for approximately 10% of all of the DLBCLs and have poorer prognosis. To additionally understand this subtype of DLBCLs at the molecular level and to find genes that are differentially expressed in de novo CD5(+) DLBCLs, CD5(-) DLBCLs, and mantle cell lymphomas, which also have poor prognosis, we performed gene expression profiling using cDNA microarray technology. Data from a total of 9 samples of CD5(-) DLBCLs, 11 samples of de novo CD5(+) DLBCLs, and 10 samples of mantle cell lymphomas were acquired. A series of genes were identified that distinguish these three types of lymphomas. Among DLBCL cases, integrin beta1 and/or CD36 adhesion molecules were overexpressed in most cases of CD5(+) DLBCL. An immunohistochemical confirmation study revealed that integrin beta1 was expressed on lymphoma cells, which may account for the high extranodal involvement and poor prognosis of CD5(+) DLBCLs. In contrast, CD36 was overexpressed on vascular endothelia in CD5(+) DLBCLs, although there was no difference in vascularity detected by von Wilbrand factor antibody between CD5(+) and CD5(-) DLBCLs. Those results suggest that CD5(+) and CD5(-) DLBCLs have different gene expression signatures in both tumor cells and their vascular systems.  相似文献   
79.
Choriocarcinoma is a highly aggressive beta-subunit of human chorionic gonadotropin (betaHCG)-producing germ cell tumor. In men, it is a rare neoplasm and can arise in the testes or in various extragonadal locations such as the retroperitoneum, mediastinum, and pineal body. We present a highly unusual case of a middle-aged man with primary metastatic betaHCG-producing choriocarcinoma of the right thigh along with right lower-extremity venous thrombosis. We comment on prognostic variables as well as discuss several theories to account for the unusual location of his choriocarcinoma.  相似文献   
80.
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