Gas-liquid chromatographic properties of positional isomers of methyl thia, selena, and tellura laurate analogs

Gas-liquid chromatographic analyses of three complete series of synthetic positional isomers of methyl thia, selena, and tellura laurate analogs were carried on a nonpolar (SE-30) and a polar (SP-2330) stationary phase. The average ECL (equivalent chain length) values of the thia, selena, and tellura laurate on SE-30 stationary phase were 13.8, 14.8, and 15.7, respectively, while on SP-2330 the average values for the same series were 17.1, 19.0, and 19.1, respectively. Positional isomers with the heteroatom at the 2-position exhibited the lowest ECL values, while those with the heteroatom at the omega-1 position gave the highest ECL values and were readily separated from the other positional isomers of the same series of analogs by this technique.     

Medullary carcinoma of the thyroid in Norway. Clinical course and endocrinological aspects

A study of the clinical, biochemical and histological findings of 57 patients with medullary thyroid carcinoma (MCT) in Norway, is presented. The diagnosis was established by light and electron microscopy and by measurements of immunoreactive calcitonin (iCT) in serum. The major factor influencing the prognosis was the extension of the disease at presentation. None of the 24 patients with tumour confined to the thyroid gland have died of the disease, and serum iCT was normal in 15 patients. Of 19 patients with regional lymph node metastes only 11 are alive 1 to 14 years after treatment, and of these 9 had increased serum iCt. 14 patients technically inoperable and/or with distant metastases, 12 have died of MCT, 1 are alive with elevated serum iCT. Of 14 patients with raised serum iCT, 8 have no clinical recurrence of the disease from 1 to 15 years after the operation. MCT-associated diseases were found in 8 patients, chronic thyroiditis in 10. Serum iCT was measured in 249 relatives of 42 patients, and abnormal elevations were found in 11 members of 6 families.     

Interface electrochemical corrosion behaviour of alclad Al–Zn–Mg–Cu–Cr Al alloy adhesively bonded with carbon fibre reinforced plastic stiffener

Abstract

Stiffening of Al alloy aircraft structures with carbon fibre reinforced plastic laminate called ‘patches’ is considered as a viable option to enhance fatigue life. Interface so created between the reinforcement and Al alloy structure is potential site for crevice corrosion attack. Therefore, studies were conducted to investigate the interface corrosion behaviour of peak and two-step aged Al–Zn–Mg–Cu–Cr alclad alloy with and without the patch and examine the possibility to control the interfacial attack with the addition of cerium chloride inhibitor exposed to 3·5 wt-% NaCl solution for the durations of 2 and 168 h. Electrochemical impedance spectroscopy revealed that the interface attack was significantly reduced by the addition of 1000 ppm cerium chloride. The response of the peak and two-step aged alloy for such an addition was further investigated and found that the alloy under step aged condition behaves better than that of the peak aged condition.     

Enrichment of Noodles with Soy Flour and Carrot Powder

Noodles were produced from four flour blends of whole wheat, wheat-cassava, wheat-cassava-soy flour and wheat-cassava-carrot flour blends respectively. The flours were analyzed for proximate analysis, functional properties and total carotenoid content. The cooking time of all samples was also determined. Results show that there were significant differences (p < 0.05) between values obtained for moisture content, protein and total carbohydrates (p < 0.05) while values for fat and ash contents of the samples were not significantly different (p > 0.05). The functional properties also showed significant differences (p < 0.05) between the pasting properties except for pasting temperature and the cooking time of the samples. The total carotenoid content of the dried carrot sample was found to be 28.34 mg/100 g dry weight basis, while the noodle sample containing 10% dried carrot sample (CSC4) had a total carotenoid content of 1.80 mg/100 g dry weight basis. The results suggest that noodles made from the different flour blends can compare favourably with conventional noodles made from wheat flour in quality and that carrot flour can be used for noodle enrichment.     

Enhancing the Environmentally Assisted Cracking Resistance of Aircraft Quality Al Alloy of Type AA7075 Stiffened with Polymer Matrix Composite Using Cerium Chloride Inhibitor

This study explores a methodology to raise environmentally assisted cracking resistance of alclad Al–Zn–Mg–Cu (AA7075) alloy, used in aircraft structures, stiffened with polymer matrix composite asymmetric patch in order to suppress growth of fatigue cracks. Fracture mechanics studies of adhesively bonded center-pre-cracked Al alloy specimens having stiffeners were carried out in 3.5 wt% sodium chloride environment to understand the effect of cerium chloride inhibitor on the threshold stress intensity for stress corrosion cracking as well as the second-stage (steady-state) crack growth rate. It was observed that in the peak- and the two-step-aged tempers, the crack growth rate of the alloy reduced by two and a half, and four times, respectively, while the threshold stress intensity increased by 14–15% due to the addition of 1000 ppm of this inhibitor. The study offers a method to enhance significantly life of aging aircrafts stiffened with polymer matrix composite.     

Endocrine response and resistance in breast cancer: a role for the transcription factor Fos

The concentration of the tumor marker CA 19-9 is influenced by the patient's secretor status and Lewis genotype. The aim of this study was to establish novel reference intervals for CA 19-9 in serum based on secretor and Lewis genotypes, to investigate the biological variation of CA 19-9, and to evaluate the utility of Lewis and secretor genotyping on a group of individuals with serologically defined Lewis phenotypes. CA 19-9 was measured in serum of 500 healthy individuals. Secretor and Lewis genotypes were determined by sequencing and PCR-cleavage methods. Significant differences were found between subgroups with different Lewis and secretor genotypes. Genotype-based reference intervals for CA 19-9 are presented. The upper reference limit for all individuals was 28.7 kilounits/L; for secretors and nonsecretors, the upper reference limits were 12.4 and 61.2 kilounits/L, respectively. The analytical imprecision (CVA) was 9.8%, the within-subject variability (CVI) was 15.8%, and the between-subject variability (CVG) was 102.2%. Good agreement was found between Lewis and secretor genotyping and conventional blood grouping. Genotype-based reference intervals may be a way to increase the clinical utility of CA 19-9. On the basis of the calculation of a critical difference for sequential values (significant at P 相似文献   

Pharmacokinetics of moricizine in young patients

Moricizine is a novel phenothiazine antiarrhythmic agent that depresses the activity of ectopic foci, has a low incidence of adverse effects relative to other agents, and is useful in treating pediatric atrial ectopic tachycardia. A study was conducted to determine the pharmacokinetics of moricizine in children after oral administration. Moricizine was isolated from frozen serum obtained from four male patients (ages 7, 8, 9, and 18 years) receiving the drug for supraventricular tachycardia and analyzed by high-performance liquid chromatography with ultraviolet detection according to an established protocol. Peak serum levels were between 400 and 2000 ng/mL. Elimination of moricizine did not follow simple single-compartment pharmacokinetics. In three patients we observed an increase or slower decline in blood level occurring after 4 hours. Because of the paroxysmal nature of the tachycardias, decreases in patient heart rate could not be correlated with moricizine blood level. These results suggest that the pediatric pharmacokinetics of moricizine excretion are complex and may differ from those seen in adults.     

Dynamics of neurotic stuttering in preschool age

The report deals with the clinical picture and dynamics of neurotical stuttering in children of preschool age. The authors studied 65 such patients aged from 3-6 years. Two forms of the disease development were distinguished: benign and unfavourable or protracted. It was possible to detect a connection between speech and neurotic disorders. Factors influencing the unfavourable development of neurotic stuttering were the following: hereditary loading of speech pathology, unfavourable microsocial environment, somatic weakness, expressiveness and stability of neurotic symptoms.     

Rubber seed oil quality assessment and authentication

Physicochemical and instrumental characterization of rubber (Hevea brasiliensis Müll. Arg.) seed oil (RSO) was carried out for the purposes of quality assessment, identification, and authentication. Properties such as color (Lovibond), specific gravity, percent FFA (as oleic acid), acid value, saponification value, iodine value, and viscosity were determined. FA composition and M.W. averages of RSO were determined using GLC and gel permeation chromatography (GPC), respectively. Structural features of RSO were also determined using FTIR, ¹H NMR, and ¹³C NMR spectroscopy. The natural form of RSO is highly acidic (acid value≈43.6 mg KOH/g). The saturated FA are palmitic (17.50%) and stearic (4.82%), and the main unsaturated FA are oleic (25.33%), linoleic (37.50%), and linolenic (14.21%). The oil can be classified as semidrying. GPC shows an unusual peak that is due to a very high M.W. (≈38,800) fraction that is not found in the chromatogram of known vegetable oils and is therefore unique to RSO. FTIR, ¹H NMR, and ¹³C NMR analyses confirmed that RSO is composed mainly of TAG of saturated and unsaturated FA. Functional groups such as carbonyl, olefinic unsaturation, esters, glyceryl, methylene, and terminal methyl that are present in vegetable oils are also present in RSO.