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61.
Fine grinding of barley grain has traditionally been considered to be a potential risk to rumen function, feed intake and milk yield. These concerns are thought to be reduced by steam-rolling or coarse dry rolling. We hypothesized that finely ground barley grain is as effective in stimulating feed intake and milk production as are dry- and steam-rolled barley grain, and so the objective was to determine effects of feeding either (1) finely ground, (2) steam-rolled, (3) finely dry-rolled, or (4) coarsely dry-rolled barley grain on rumen fermentation, digestibility and milk yield and composition. Eight multiparous midlactation Holstein cows were used in a replicated 4×4 Latin square design experiment with four periods of 21 d. Diets contained 256 g barley grain/kg on a dry matter (DM) basis. Processing method did not affect milk yield and composition, DM intake, rumen pH and volatile fatty acids, fecal and urine pH, and apparent total tract nutrient digestibility. Results suggest that finely ground barley grain is no different than dry-rolled and steam-rolled barley grains in stimulating feed intake and productivity of midlactation cows, when 256 g of dietary DM/kg is barley grain.  相似文献   
62.
Neutron capture therapy (NCT) is a targeted radiotherapy for cancer treatment. In this method, neutrons with a spectra/specific energy (depending on the type of agent used for NCT) are captured with an agent that has a high cross-section with these neutrons. There are some agents that have been proposed in NCT including 10B, 157Gd and 33S. Among these agents, only 10B is used in clinical trials. Application of 157Gd is limited to in-vivo and in-vitro research. In addition, 33S has been applied in the field of Monte Carlo simulation. In BNCT, the only two delivery agents which are presently applied in clinical trials are BPA and BSH, but other delivery systems are being developed for more effective treatment in NCT. Neutron sources used in NCT are fission reactors, accelerators, and 252Cf. Among these, fission reactors have the most application in NCT. So far, BNCT has been applied to treat various cancers including glioblastoma multiforme, malignant glioma, malignant meningioma, liver, head and neck, lung, colon, melanoma, thyroid, hepatic, gastrointestinal cancer, and extra-mammary Paget's disease. This paper aims to review physical, dosimetric and clinical aspects as well as delivery systems in NCT for various agents.  相似文献   
63.

Objective

Rheumatoid arthritis (RA) is one of the most prevalent chronic autoimmune diseases; it typically involves the hands, wrists, ankles, and eventually all joints. Some studies have reported that zinc serum levels are lower in patients with RA than in healthy individuals.

Materials and Methods

Seventy-nine patients with RAwere selected. The patients were all less than 75 years old and were diagnosed by a rheumatologist. Serum zinc levels were measured using the flame photometry method with a blood sample of 5 mL. The relationship between the average serum zinc level and disease activity was analyzed based on the DAS28 scoring scale for different RA groups. The significance threshold was set at p<0.05. Data analyses were implemented in SPSS 22.0.

Results

There was a significant inverse relationship between the serum zinc levels and disease activity. Chi-square tests were used to compare zinc serum levels with respect to disease activity. There were significant differences in zinc levels among three groups of patients with different levels of disease severity, such that disease activity increased as the serum zinc level decreased (p<0.001).

Conclusion

There was a significant inverse relationship between the serum zinc level and RA activity based on the DAS28 score. Therefore, it is recommended that mineral deficiencies should be addressed by optimizing the zinc supply along with other standard medications in order to reduce RA activity.
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64.
65.
This study describes the length–weight and length–length relationships for three cyprinid species from the Bibi‐Sayyedan River (western Isfahan provinces, Iran). The slope parameter (b) values in the length–weight relationship equations were determined as 3.0729 for Alburnus mossulensis Heckel, 1843; 2.8509 for Barbus lacerta Heckel, 1843; and 3.0864 for Chondrostoma regium (Heckel, 1843). This study presents the first LWR and LLR references for these species in the Bibi‐Sayyedan River.  相似文献   
66.
Fusarium mycotoxins such as deoxynivalenol (DON) can occur in cereals conjugated to glucose and probably also to other sugars. These conjugates, which are often referred to as ??masked mycotoxins??, will not be detected with routine analytical techniques. Furthermore, it is suspected that the parent toxin may again be released after hydrolysis in the digestive tracts of animals and humans. Today, our knowledge of the occurrence of these compounds in cereal grains is limited. In this paper, a LC-MS/MS method for the simultaneous determination of DON, deoxynivalenol-3-??-d-glucoside (DON-3-glucoside), 3 acetyl-DON, nivalenol, fusarenon-X, diacetoxyscirpenol, HT-2 toxin, and T-2 toxin in naturally (n?=?48) and artificially (n?=?30) contaminated cereal grains (wheat, barley, oat, rye triticale) is reported. The method has also been applied to whole fresh maize plant intended for production of maize silage (n?=?10). The samples were collected from the harvest years 2006?C2010, The results show that DON-3-glucoside and DON co-occurred in cereal grains and, especially in several of the highly contaminated samples, the concentration of the glucoside can be relatively high, corresponding to over 37?% of the DON concentration. The DON-3-glucoside levels in both the naturally and in the artificially grain inoculated with Fusarium were second only to DON, and were generally higher than those of the other tested trichothecenes, which were found at low concentrations in most samples, in many cases even below the detection limit of the method. This argues for the importance of taking DON-3-glucoside into account in the ongoing discussion within the European Community concerning exposure re-evaluations for setting changed values for the tolerable intake for DON. Our results indicate that, in the naturally contaminated grains and in the Fusarium infested cereal grains (winter and spring wheat, oat, triticale), the concentration level of DON-3-glucoside is positively correlated to the DON content. When the DON concentration is high, then the content of DON-3-glucoside will most probably also be high and vice versa.  相似文献   
67.

Aims

Granulocyte colony stimulating factor (G-CSF), a new neuroprotective agent, binds to its specific receptors in the brain. In this study we hypothesized that at least a part of G-CSF's neuroprotective effect may be mediated through its interaction with other proteins in the brain.

Main methods

Using an immunoprecipitation (IP) kit, at first the antibody of G-CSF was covalently crosslinked to protein A/G agarose. Then the mouse brain or PC12 cell lysate mixed with G-CSF was added to the agarose beads plus antibody. After immunoaffinity isolation of target proteins, gel electrophoresis was performed and protein bands were identified using MALDI-TOF/TOF and MASCOT software.

Key findings

Our data show that G-CSF physically binds to cellular proteins like sodium/potassium-transporting ATPase, beta actin, aldehyde dehydrogenase, regucalcin and glutathione-s-transferase. These proteins are involved in membrane transportation, cell structure, signal transduction, enzymes involve in calcium related cell signaling and redox homeostasis.

Significance

Interaction of G-CSF with these proteins can explain some of its pharmacological effects in the CNS.  相似文献   
68.
Peptic ulcer disease (PUD) is a common illness, affecting a considerable number of people world-wide, and its occurrence can be influenced by environmental and genetic factors. Heat shock proteins (HSPs) function mostly as molecular chaperones, and are induced by various stresses. The A to G transition at position 1267 of the HSPA1B gene was shown to correlate with changes in the level of HSPA mRNA expression. Here, the relation between A1267G polymorphism of the HSPA1B gene and risk of peptic ulcer in the Iranian population was evaluated. One hundred subjects, who underwent gastroscopy, took part in the study. DNA samples extracted from the biopsy tissues were genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). After gastroscopy, peptic ulcer was diagnosed for 50 patients; among them the distribution of AA/AB/BB genotypes was 10, 88, and 2%, respectively. As for the other 50 subjects (without peptic ulcer) included in the control group, the AA/AB/BB genotypes were identified as 40, 52 and 8%, respectively. A significant association was found between the HSPA1B genotype and peptic ulcer (6.76 OR; 95% CI, 2.26–20.2; p = 0.0006). Thus, the HSPA1B A1267G polymorphism may be a marker of susceptibility to peptic ulcer.  相似文献   
69.

Background

Task group number 40 (TG-40) of the American Association of Physicists in Medicine (AAPM) has recommended calibration of any brachytherapy source before its clinical use. GZP6 afterloading brachytherapy unit is a 60Co high dose rate (HDR) system recently being used in some of the Iranian radiotherapy centers.

Aim

In this study air kerma strength (AKS) of 60Co source number three of this unit was estimated by Monte Carlo simulation and in air measurements.

Materials and methods

Simulation was performed by employing the MCNP-4C Monte Carlo code. Self-absorption of the source core and its capsule were taken into account when calculating air kerma strength. In-air measurements were performed according to the multiple distance method; where a specially designed jig and a 0.6 cm3 Farmer type ionization chamber were used for the measurements. Monte Carlo simulation, in air measurement and GZP6 treatment planning results were compared for primary air kerma strength (as for November 8th 2005).

Results

Monte Carlo calculated and in air measured air kerma strength were respectively equal to 17240.01 μGym2 h−1 and 16991.83 μGym2 h−1. The value provided by the GZP6 treatment planning system (TPS) was “15355 μGym2 h−1”.

Conclusion

The calculated and measured AKS values are in good agreement. Calculated-TPS and measured-TPS AKS values are also in agreement within the uncertainties related to our calculation, measurements and those certified by the GZP6 manufacturer. Considering the uncertainties, the TPS value for AKS is validated by our calculations and measurements, however, it is incorporated with a large uncertainty.  相似文献   
70.

Colorectal cancer (CRC) is an increasingly common medical issue affecting millions worldwide, and contribution of the body’s trace elements to CRC is arguable. The concentrations and buffered status of selenium, iron, copper, zinc, and phosphorus in blood and large intestinal tissues of CRC patients are, respectively, variable and vital for cell physiology. The aim of this study was to assess selenium, iron, copper, zinc, and phosphorus variations in blood and colorectal epithelia along with examining the expression of mismatch repair proteins in CRC patients with/without metastasis for potential diagnosis/therapy. Concentrations of selenium, iron, copper, zinc, and phosphorus in blood of healthy versus CRC patients and colorectal epithelia (adenocarcinomatous versus non-adenocarcinomatous/control) were measured in 40 CRC patients (55.87 ± 11.9 years old) with/without metastasis before surgery using ICP-OES. Mismatch repair (MMR) protein expression was analyzed through histopathological/immunohistochemistry assays, which was sparse in 5 CRC patient’s colorectal tissues (12%). Compared with healthy individuals, blood and colorectal tissue’s levels of phosphorus, copper, and iron were significantly higher in the CRC patients, and more pronounced in metastatic CRC patients; conversely, blood and colorectal tissue’s selenium levels were significantly lower in metastatic patients. Unlike blood zinc, cancerous colorectal tissue’s zinc concentration was significantly lower in CRC patients compared to healthy control cohorts. There was no significant difference on the measured elements in samples from CRC patients with MMR compared to CRC patients with MMR+. Receiver operating characteristic analysis revealed a correlation of blood iron, zinc, copper, and phosphorus to CRC, and inappropriately low levels of blood and colorectal selenium correlated with exacerbated metastasis. Altered levels of selenium, iron, copper, zinc, and phosphorus in vivo may impact the pathogenesis and detection of CRC, and their diagnostic/therapeutic potential in CRC would be revealing.

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