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151.
152.

Background

The effect of tranexamic acid (TXA) on bleeding and improvement of surgical field during functional endoscopic sinus surgery (FESS) is not clear yet. This study was conducted to answer this question.

Methods

This trial was conducted on 60 patients with chronic sinusitis at Beasat Hospital, Hamadan, Iran, from April to November 2013. Thirty patients in the intervention group received three pledgets soaked with TXA 5% and phenylephrine 0.5% for 10 minutes in each nasal cavity before surgery. Thirty patients in the control group received phenylephrine 0.5% with the same way. The amount of bleeding and the quality of surgical field were evaluated at 15, 30, and 45 minutes after the start of surgery using Boezaart grading.

Results

The quality of the surgical field in the intervention group compared to the control group was significantly better in the first quarter (P = 0.002) and the second quarter (P = 0.003) but not in the third quarter (P = 0.163). Furthermore, the amount of bleeding was much less during all periods in the intervention group than in the control group (P = 0.001).

Conclusion

Topical TXA can efficiently reduce bleeding and improve the surgical field in FESS in patients with rhinosinusitis. Based on these findings, topical TXA may be a useful method for providing a suitable surgical field during the first 30 minutes after use.

Trial Registration

Iranian Registry of Clinical Trials IRCT201212139014N15  相似文献   
153.
2,4-Dinitroanisole (DNAN) is a low sensitive melt-cast chemical being tested by the Military Industry as a replacement for 2,4,6-trinitrotoluene (TNT) in explosive formulations. Little is known about the fate of DNAN and its transformation products in the natural environment. Here we report aerobic biotransformation of DNAN in artificially contaminated soil microcosms. DNAN was completely transformed in 8 days in soil slurries supplemented with carbon and nitrogen sources. DNAN was completely transformed in 34 days in slurries supplemented with carbons alone and persisted in unamended microcosms. A strain of Bacillus (named 13G) that transformed DNAN by co-metabolism was isolated from the soil. HPLC and LC–MS analyses of cell-free and resting cell assays of Bacillus 13G with DNAN showed the formation of 2-amino-4-nitroanisole as the major end-product via the intermediary formation of the arylnitroso (ArNO) and arylhydroxylamino (ArNHOH) derivatives, indicating regioselective reduction of the ortho-nitro group. A series of secondary reactions involving ArNO and ArNHOH gave the corresponding azoxy- and azo-dimers. Acetylated and demethylated products were identified. Overall, this paper provides the evidence of fast DNAN transformation by the indigenous microbial populations of an amended soil with no history of contamination with explosives and a first insight into the aerobic metabolism of DNAN by the soil isolate Bacillus 13G.  相似文献   
154.
Polycyclic aromatic hydrocarbons (PAHs) are one of the toxic persistent organic pollutants, have global environmental concern. Seed germination and early seedling development are the initial handicaps for plant establishment in phytoremediation program. Assisted phytoremediation by plant growth regulators may be a potential solution for these problems. Hence, we investigated the effects of seed treatment with various concentrations (0.01, 1.0, 100?nM) of 24-epibrassinolide (EBR) in tomato under graded levels (30, 100, 300???M) of a three-ring PAH namely phenanthrene (PHE). Delayed and decreased seed germination, reduced length and fresh weight (FW) of shoot and root were observed following 10?days of PHE exposure in a dose dependent manner. Chlorophyll fluorescence study suggested a possible photoinhibition and damage to photosynthetic apparatus under PHE exposure. However, seed treatment with EBR improved seed germination and increased length and FW of shoot and root. In addition, EBR remarkably restored the studied chlorophyll fluorescence parameters towards control levels. Different responses in antioxidant enzymes were observed following PHE exposure, while malondialdehyde (MDA) content was increased in a concentration dependent manner. EBR treatment prior to PHE exposure remarkably increased the activities of antioxidant enzymes over PHE alone, but decreased the MDA contents both in shoot and root of young tomato seedlings. Considering all the studied parameters, seed treatment with 1.0?nM EBR was most effective followed by 100 and 0.01?nM for the improvement of germination and seedling growth under PHE stress in tomato.  相似文献   
155.
Close to 50 genetic loci have been associated with type 2 diabetes (T2D), but they explain only 15% of the heritability. In an attempt to identify additional T2D genes, we analyzed global gene expression in human islets from 63 donors. Using 48 genes located near T2D risk variants, we identified gene coexpression and protein-protein interaction networks that were strongly associated with islet insulin secretion and HbA(1c). We integrated our data to form a rank list of putative T2D genes, of which CHL1, LRFN2, RASGRP1, and PPM1K were validated in INS-1 cells to influence insulin secretion, whereas GPR120 affected apoptosis in islets. Expression variation of the top 20 genes explained 24% of the variance in HbA(1c) with no claim of the direction. The data present a global map of genes associated with islet dysfunction and demonstrate the value of systems genetics for the identification of genes potentially involved in T2D.  相似文献   
156.
157.
Biodegradation of the Nitramine Explosive CL-20   总被引:5,自引:2,他引:3       下载免费PDF全文
The cyclic nitramine explosive CL-20 (2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane) was examined in soil microcosms to determine whether it is biodegradable. CL-20 was incubated with a variety of soils. The explosive disappeared in all microcosms except the controls in which microbial activity had been inhibited. CL-20 was degraded most rapidly in garden soil. After 2 days of incubation, about 80% of the initial CL-20 had disappeared. A CL-20-degrading bacterial strain, Agrobacterium sp. strain JS71, was isolated from enrichment cultures containing garden soil as an inoculum, succinate as a carbon source, and CL-20 as a nitrogen source. Growth experiments revealed that strain JS71 used 3 mol of nitrogen per mol of CL-20.  相似文献   
158.
This study describes the dispersal traits and dispersal patterns of 51 perennial plant species belonging to 19 families in an oro-Mediterranean thorn cushion plant formation on the High Atlas, Morocco. Diaspore type, mass, number, antitelechoric mechanisms and dispersal time were studied with respect to growth forms, dispersal modes and spatial dispersal. Species spanned 105 range of diaspore mass, which coincided with those found in other high mountain regions. Diaspore mass was significantly higher in trees and shrubs than in semi-shrubs and perennial herbs. Barochorous and zoochorous species are more likely to have heavy diaspores, whereas anemochorous and ballistic species have a medium diaspore mass and semachorous and ombro-hydrochorous species have low diaspore mass. Diaspore number was significantly higher in trees and shrubs than in semi-shrubs and perennial herbs. The barochorous, ombro-hydrochorous and zoochorous species tended to produce higher diaspore numbers than species with other dispersal modes. Bradyspory was well-developed by trees and large shrubs dispersed by biotic vectors. Synaptospermy was represented by its long dispersal component. Myxospermy was significantly associated with semi-shrubs and perennial herbs with restricted spatial dispersal. It seems that ombro-hydrochory combined with myxospermy and a high number of light seeds is an efficient mechanism that ensures successful establishment of the most typical and endemic thorn cushion plant species, such as Alyssum, Vella and Ormenis. In our study area, the highest dispersal availability was synchronized with the dry summer season (July–August) and the beginning of the rainy months (September). The dispersal peak for the wind-dispersed species, which is the most effective primary dispersal mode, occurs during the dry season, while dispersal for the biotic-dispersed species takes place throughout the year.  相似文献   
159.
Objective:  To assess the diagnostic value of clot examination for satisfactory processing and confirmation of malignancy in serous effusions in routine cytological evaluation and compare the results with those of conventional smear and cell block preparations.
Methodology:  Body cavity fluids ( n  = 600) received in our laboratory were processed according to a pre-designed protocol for the study as follows: Day1: on receipt of the specimen, smears were made and a cell block was prepared from the sediment. Day2: after overnight sample storage of the remaining specimen at 2–8 °C all fluids were examined for the presence of a clot at the bottom of the container. Fluids in which clot had formed were fixed in formalin. The clot was then placed on a lens paper, wrapped and processed routinely. Diagnostic yields were compared.
Results:  In this study, we included 600 cases of serous fluids from pleural, pericardial and peritoneal effusions. In 73% ( n  = 437) of samples, clot formation was seen, while in 27%, ( n  = 163) no clot had formed. Routine smear and cell block preparations showed malignant cells in 9.6% ( n  = 42). However, with the addition of the clot preparation, the number of cases in which atypical/malignant cells were seen increased from 42 to 85 (19.4%), with a P  < 0.001. Special stains and immunohistochemistry (IHC) were also performed on clot preparations in 10 difficult cases.
Conclusion:  Clot preparation from body cavity fluids on the second day can be used as an adjunct to smear and routine cell block preparation to improve the accuracy and yield of the cytological diagnosis and may also be of great help for special studies such as IHC staining.  相似文献   
160.
The aim of this study was to assess the cytotoxicity of chlorhexidine gluconate (CHG) on human blood lymphocytes as a useful ex vivo model for accelerated human toxicity studies. Using biochemical and flow cytometry assessments, we demonstrated that addition of CHG at 1 μM concentration to human blood lymphocytes induced cytotoxicity following 6 h. The CHG‐induced cytotoxicity on human blood lymphocytes was associated with intracellular reactive oxygen species generation, mitochondrial membrane potential collapse, lysosomal membrane injury, lipid peroxidation, and depletion of glutathione. According to our results, CHG triggers oxidative stress and organelles damages in lymphocytes which are important cells in defense against foreign agents. Finally our findings suggest that using of antioxidants and mitochondrial/lysosomal protective agents could be of benefit for the people in the exposure with CHG.  相似文献   
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