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51.
52.
Probiotics and Antimicrobial Proteins - Nowadays, cancer remains a major cause of death affecting millions of people. Currently, the antimicrobial peptides (AMPs) as potent anticancer therapeutic...  相似文献   
53.
In present study, the capabilities of multiple linear regression (MLR) and adaptive neuro-fuzzy inference system (ANFIS) in developing pedotransfer functions (PTFs) for estimating geometric mean diameter (GMD) and mean weight diameter (MWD), from routine soil properties and combination of routine soil properties and fractal dimension of aggregates were evaluated. For this reason 101 samples were collected form the Northwest of Iran and some their properties such as soil texture, pH, cation exchange capacity (CEC), and organic matter (OM), fractal dimension of aggregates between number-diameter (Dn), mass-diameter (Dmt), and bulk density-diameter (Dmy) were determined and used as an input variables for determining of mean weight diameter (MWD) and geometric mean diameter (GMD) by MLR and ANFIS PTFs. Results showed that the application of fractal dimension of aggregates as a predictor in two methods improved the accuracy of PTFs. As well as, results showed that ANFIS have greater potential for determination of the relationships between soil aggregate stability indices and other soil properties in compared with MLR. Therefore using of adaptive neuro-fuzzy inference system (ANFIS) in developing pedotransfer functions is recommended.  相似文献   
54.
The biopharmaceutical industry gains enormous flexibility in production processes by using sterilized preassembled single-use devices. Gamma irradiation is an established sterilization technology that may be restricted in the future by the availability of 60Co as irradiation source and irradiation capacities. X-ray technology is considered an alternative type of radiation for sterilizing SU equipment. In the context of extractables and leachables—one concern connected with the use of single-use process equipment—the effect of X-ray irradiation on the extractables profile of the materials needs to be compared to established gamma irradiation to qualify this alternative technology. An approach is presented to obtain robust and comprehensive extractables data for materials used in SU devices after sterilization either using X-ray or gamma irradiation. A careful selection of the test items and the test design allows a one-to-one comparison of data obtained from a combination of orthogonal analytical techniques. The extractables of a modern SU film material and the copolyester Tritan™ are evaluated. The data presented allow a risk evaluation on the safety of this new sterilization modality for biopharmaceutical applications. It is demonstrated that the extractables profile of a polymer is not affected by the type of irradiation used for sterilization.  相似文献   
55.
A new class of galactooligosaccharides has been identified from the terrestrial cyanobacterium Nostoc commune by MS and NMR techniques. These consist of beta-D-galactofuranosyl-(1-->6)-[beta-D-galactofuranosyl-(1-->6)]n-beta-d-1,4-anhydrogalactitols with n ranging from 2 to 8, corresponding to compounds designated 1 through 7. In total these saccharides amounted to approximately 0.35% of the dry thallus of N. commune, while in several other cyanobacteria they were not detected. Possibly they play some role in protection from damage by heat and desiccation as suggested by experiments with heterologous systems. For example, phosphoglucomutase (EC 2.7.5.1) from rabbit muscle was protected against heat inactivation by these oligosaccharides, and alpha-amylase (EC 3.2.1.1) from porcine pancreas by the oligosaccharides 6 and 7. The homologues of lower molecular mass, however, enhanced heat sensitivity of alpha-amylase. The viability of Escherichia coli was completely abolished by desiccation, whereas in the presence of 4 survival rates were approximately 50% of controls not subjected to desiccation. The newly identified saccharides are compared with known galactofuranose-based oligo- and polysaccharides and possible biological functions of them are discussed.  相似文献   
56.

Background

Recent attention has focused on understanding the role of the brain-renin-angiotensin-system (RAS) in stroke and neurodegenerative diseases. Direct evidence of a role for the brain-RAS in Parkinson's disease (PD) comes from studies demonstrating the neuroprotective effect of RAS inhibitors in several neurotoxin based PD models. In this study, we show that an antagonist of the angiotensin II (Ang II) type 1 (AT1) receptor, losartan, protects dopaminergic (DA) neurons against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) toxicity both in primary ventral mesencephalic (VM) cultures as well as in the substantia nigra pars compacta (SNpc) of C57BL/6 mice (Fig. 1).

Results

In the presence of exogenous Ang II, losartan reduced MPP+ (5 μM) induced DA neuronal loss by 72% in vitro. Mice challenged with MPTP showed a 62% reduction in the number of DA neurons in the SNpc and a 71% decrease in tyrosine hydroxylase (TH) immunostaining of the striatum, whereas daily treatment with losartan lessened MPTP-induced loss of DA neurons to 25% and reduced the decrease in striatal TH+ immunostaining to 34% of control.

Conclusion

Our study demonstrates that the brain-RAS plays an important neuroprotective role in the MPTP model of PD and points to AT1 receptor as a potential novel target for neuroprotection.  相似文献   
57.

Background  

The enormity of the information contained in large data sets makes it difficult to develop intuitive understanding. It would be useful to have software that allows visualization of possible correlations between properties that can be associated with a core data set. In the case of bacterial genomes, existing visualization tools focus on either global properties such as variations in composition or detailed local displays of the features that comprise the annotation. It is not easy to visualize other information in the context of this core information.  相似文献   
58.
Objective: Severe obesity is a clear indication for appropriate, effective weight loss therapy. One option is operative intervention, e.g., gastric banding. Risks of the operation and therapeutic alternatives need to be comprehensibly presented to the patient. The literature has shown that better informed consent is obtained using information presented in a multimedia/video‐based format. The current study developed and evaluated a multimedia program aimed at obtaining informed consent from obese patients before gastric banding. Research Methods and Procedure: An interactive multimedia program was developed with information about preoperative examinations, the operation itself, hospital stay, operative risks, alternative therapies, and the pathophysiology and health risks of obesity. Two groups (Group 1, n = 20, mean age 38 years, informed consent attained with conventional document information; Group 2, n = 20, mean age 37 years, informed consent attained with additional multimedia information) were interviewed regarding comprehensibility of the information presented, personal satisfaction, and anxiety levels during the informed consent process. Results: Group 2 showed significantly better (p < 0.05) understanding of the presented information and higher levels of satisfaction with the informed consent process. Anxiety levels did not significantly differ between the two groups. Discussion: Because patient satisfaction with the informed consent process and understanding of the presented information significantly improved, the multimedia program clearly benefits both surgeons and patients. Personal contact from the surgeon remains essential. High volumes of information presented in multimedia format do not alleviate patient anxiety, and personal contact may be beneficial.  相似文献   
59.
60.
This report describes the isolation of Aeromonas veronii biovar sobria as the causative enteropathogen of diarrhoea in an oncological patient after failure of detection of other infectious agents. The case points out the severe and long course of the infection, the diagnostic dilemma, and the prompt recovery after antibiotic treatment.  相似文献   
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