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The first direct one-pot approach for the synthesis of N-substituted amidoximes from secondary amides or the intermediate amides has been developed. Through the Ph3P–I2-mediated dehydrative condensation, a variety of N-aryl and N-alkyl amidoximes (R1(C Created by potrace 1.16, written by Peter Selinger 2001-2019 NOH)NHR2, where R1 or R2 = aryl, alkyl, or benzyl) were readily afforded under mild conditions and short reaction times. The synthetic application of the obtained amidoximes has also been demonstrated through the formation of 1,2,4-oxadiazolones via base-mediated carbonylative cyclization with 1,1′-carbonyldiimidazole.

Ph3P–I2 mediated one-pot synthesis of N-substituted amidoximes via imidoyl iodide was developed. The synthesis of 1,2,4-oxadiazol-5-ones was also demonstrated.  相似文献   
3.
Experimental and data analysis approaches in multidimensional gas chromatography (MDGC) comprising comprehensive multiple heart-cut (H/C) and comprehensive two dimensional GC (GC × GC) were developed with an example application illustrated for analysis of a technical glycol precursor sample. The GC × GC system employed a long 1D (30 m) and a short 2D (5 m) column with a flow modulator and a Deans switch (DS) as a splitter; meanwhile. The H/C system was applied solely as a DS located between long 1D (30 m) and 2D (60 m) columns without use of cryogenic trapping devices. The effects of injection time and 2D column flow in GC × GC and the impacts of H/C window and number of injections (total analysis time) in H/C analysis were investigated. The analysis performance for each condition was evaluated according to peak capacity and number of separated compounds. The continuum between the two techniques was then established via the relationship between analysis time and analysis performance. The separation performances were improved with longer analysis time so that the suitable condition was selected within this compromise. Under the selected conditions, volatile compounds in the technical glycol precursor sample were identified according to the match between the experimental MS spectra and first dimensional retention indices (1I) with that from the NIST2014 database and literature. An hour analysis with GC × GC resulted in a total peak capacity of 798, number of separated peaks of 61 and average MS match score of 887 ± 35; meanwhile, the corresponding numbers were improved to be 9198, 107 and 898 ± 24, respectively, with the 25 h comprehensive H/C analysis.

Experimental and data analysis approaches in MDGC comprising comprehensive H/C and GC × GC were developed with an example application illustrated for analysis of a technical glycol precursor sample.  相似文献   
4.
The weight, height and body mass index (BMI), including waist/hip ratio, serum leptin and hematological parameters of 48 male and 166 female overweight (BMI > or = 25.00) Thai volunteers who came for a physical check-up at the Out-patient Department, General Practice Section, Rajvithi Hospital, Bangkok during the period March-October 1998, were investigated. There were statistically significantly higher levels of serum leptin, mean corpuscular mean corpuscular hemoglobin concentration (MCHC) and mean corpuscular volume (MCV) in the overweight than in the control subjects. The median serum leptin concentration in overweight subjects was 19.6 (2.0-60.0 ng/ml) compared with 9.0 (range 1.0-30.0 ng/ml) in the control subjects (p < 0.001). The medians of leptin in overweight and obese males were significantly higher than those of overweight and obese females. 66.7% (32 out of 48) of overweight and obese males were found to have elevated leptin levels, while 87.3% (145 out of 166) were found in overweight and obese females. Anemia was found in 18.7% of female overweight and obese subjects, using hemoglobin as an indicator. Significant associations were found between weight, height, BMI, waist, hip, waist/hip ratio, hemoglobin, hematocrit, and serum leptin in both male and female overweight subjects. A negative correlation was found between serum leptin and hemoglobin, and hematocrit in both overweight and obese subjects.  相似文献   
5.
A marine actinomycete strain C1-2 was taxonomically characterized as the genus Streptomyces, based on whole-genome sequence analysis. The highest average nucleotide identity (ANI) value (98.96%) and digital DNA–DNA hybridization (DDH) value (90.4%) were observed between Streptomyces sp. C1-2 and Streptomyces griseoaurantiacus. Thus, Streptomyces sp. C1-2 could be identified as S. griseoaurantiacus. Genome analysis revealed that Streptomyces sp. C1-2 contained 22 biosynthetic gene clusters (BGCs) for secondary metabolites, where among them, 54% have low similarities with known BGCs. The chemical investigation led to the isolation of three new manumycin-type derivatives and two known analog antibiotics named SW-B and cornifronin B. All compounds showed antioxidant activity with the half-maximal inhibitory concentration (IC50) values in a range of 50.82 ± 0.8–112.04 ± 1.0 μg/mL with no cytotoxicity against Vero cells. This is the first report of the antioxidant property of manumycin-type derivatives. Moreover, two known compounds exhibited antifungal activity against Phytophthora capsici, Fusarium oxysporum f. sp. cucumerinum, and Magnaporthe grisea, with the minimum inhibitory concentration (MIC) values in a range of 125–500 μg/mL.  相似文献   
6.
Porcine reproductive and respiratory syndrome (PRRS) virus infection often lead to infertility in gilts and sows. Nevertheless, the impact of PRRS virus on the endometrial function has not been fully elucidated. The present study aimed to determine the effect of PRRS virus infection on the expression of oestrogen receptor (ER) α in the endometrium of gilts. Uterine tissues from 54 gilts were classified into two groups according to PRRS virus detection using immunohistochemistry (26 positive and 28 negative samples). The reproductive status was classified as prepubertal, luteal and follicular phases. The expression of ERα in the epithelium, subepithelium and glandular tissue layers of the endometrium was determined by immunohistochemistry. ERα immunostaining was detected in 22.2, 13.5 and 33.6 % of the cells in the epithelial, subepithelial and glandular tissue layers, respectively. The ERα immunostaining in the glandular layer of the endometrium in follicular-phase gilts was higher than that in prepubertal gilts (46.1 and 15.2 %, respectively, P?=?0.011). The ERα immunostaining in the glandular layer of the endometrium was positively correlated with body weight (r?=?0.138, P?=?0.020) and average daily gain (r?=?0.169, P?=?0.005) of the gilts. The ERα immunostaining in all tissue layers of the endometrium with PRRS virus detection did not differ significantly compared to that without PRRS virus (P?>?0.05). However, in prepubertal gilts, the ERα immunostaining cells in the epithelial layer of PRRS virus negative (9.5 %) tended to be lower than PRRS virus positive (26.3 %, P?=?0.196) uterine tissues. This tendency indicates some impact of PRRS virus infection on the ERα expression in prepubertal gilts.  相似文献   
7.
For a group of 73 males and 247 females, being health-conscious and from the lower middle class of Bangkok, with various degrees of the nutritional status defined by the new criteria for Asians, the relationship of anthropometric indicators and the plasma lipid status to fasting glucose, fasting plasma insulin, and the homeostasis model assessment for insulin-resistance (HOMA-IR) has been studied. For assessing differences among groups either the Mann-Whitney U-test or the Kruskal-Wallis analysis of variance for multiple comparisons were applied. Multivariate regression models were computed to assess variation of glucose, insulin, and the HOMA-IR due to the nutritional status and serum lipids. A significant increase in fasting plasma glucose for both sexes and for females for the HOMA-IR models could be observed for the group with a body-mass index (BMI) range of 23 to less than 25. Insulin concentrations and HOMA-IR correlated for both sexes, especially with BMI and hip circumference, while the variation of fasting plasma glucose is less dependent on anthropometric nutritional indicators in comparison to insulin and HOMA-IR. Only the lipid status of females weakly correlated with insulin and HOMA-IR.  相似文献   
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9.
This study aimed to 1) compare levels of high sensitivity c-reactive protein (hs-CRP), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-alpha) between overweight Thais and apparently healthy controls, and 2) investigate the association between serum hs-CRP, IL-6, and TNF-alpha levels and other biochemical parameters. A total of 180 health-conscious adults aged 25-60 years, who resided in Bangkok, participated in this study. No significant difference was found in age and sex between the overweight subjects and controls. Serum levels of hs-CRP, IL-6, TNF-alpha, glucose, lipid profile, body mass index (BMI), waist circumference (WC), hip circumference (HC) and waist hip ratio (WHR) were determined in these volunteers. The mean levels of white blood cells (WBC), uric acid, total cholesterol (TC), triglyceride (TG), and hs-CRP were significantly higher in the overweight subjects than those in the controls, whereas high density lipoprotein-cholesterol (HDL-C) values were significantly higher in the controls than the overweight subjects (p < 0.05). Hs-CRP levels were significantly positively correlated with levels of TG, BMI, WC, HC and WHR. HDL-C levels were significantly negative correlated with hs-CRP levels. In conclusion, the prevalence of elevated serum hs-CRP levels was higher in overweight subjects than controls. However, more data in larger and other population groups are needed to confirm this study.  相似文献   
10.
Socio-demographic, anthropometric assessment, dietary pattern, lifestyle of 384 Thai elderly (55 males and 329 females) aged 60–94 years, who were members of an informal social activity group, were investigated. The 3-day dietary record was determined with the help of food models by random sampling of the group (seven males and 25 females). Most of the males investigated were married (88.9%), whereas 42.9% of the females were widowed. Nearly all of the elderly investigated lived with their relatives. Only 3% of the elderly had never attended school. More elderly males than females smoked or had smoked in the past, and this applies also to their drinking habits. The health situation of the individuals investigated seemed to be satisfactory. The most frequent diseases found among the elderly were chronic diseases, such as hypertension, hyperlipidemia and diabetes mellitus. No statistically significant difference in body mass index (BMI), arm circumference (AC), and hip circumference was found between males and females. Weight, height, mid-arm muscle circumference (MAMC), arm span, waist, waist/hip ratio and blood pressure of the males were significantly higher than those of the females. Tricep skin-fold thickness (TSF) and subscapular skin-fold thickness (SST) were lower for males than for females. A total of 54.5% of the males and 50.5% of the females were found to be over-nourished. Less than 2% of all the individuals investigated were undernourished. No significant differences were observed for all nutrients between the males and females. Intake of dietary energy from food for males and females was 69.8 and 75.5%, respectively, compared with the Thai RDA. When calculating the intake of macro-nutrients as percentage of total calorie intake, about 17% of the total calorie intake was attributed to fat, 13% to protein and 70% to carbohydrate for the males. For the females, the figures were 17, 15, and 68%, respectively. Intake of calcium, phosphorus, vitamin B1, B2 and niacin seem to be inadequate for both sexes.  相似文献   
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