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91.
The influence of inborn errors of metabolism on the amino acid content, the structure and growth of human hair has been studied in patients suffering from Phenylketonuria, Cystinosis, Homocystinuria and Tyrosinosis. Examiniation of hairs under the scanning electron microscope reveals defects and abnormalities such as a plicated pattern of the cuticula in patients with Phenylketonuria and Cystinosis. The amino acid content of the hydrolized hair keratin of all patients was within normal range and did not reveal significant changes of phenylalanine, cystine, homocystine, methionine or tyrosine. Disturbance in hair growth was determined by evaluation of standardized hair root samples. The results indicate an increase in hair root atrophy with increasing severity of the disorder of amino acid metabolism.  相似文献   
92.
In the present study the results of a neurological and neurophysiological health examination of 29 aircraft factory workers chronically exposed to jet fuel vapors are presented. The exposed subjects were classified into a heavily exposed and a less heavily exposed group. The examination included a standardized clinical neurological examination, measurements of the conduction velocities in the peripheral nerves, and threshold determinations of vibratory sensations in the extremities. All 13 persons examined in the heavily exposed group and 7 of the 16 in the less heavily exposed group stated that they had repeatedly experienced acute effects (dizziness, respiratory tract symptoms, heart palpitations, a feeling of pressure on the chest, nausea, headache) of the jet fuel vapors in the inhaled air. A high rate of symptoms indicative of neurasthenia and psychasthenia and symptoms and signs indicative of polyneuropathy was observed both in the heavily exposed group and in the two groups combined in comparison with reference groups. Considering the presented facts concerning (a) the acute effects on repeated occasions, (b) the high rates of symptoms indicative of neurasthenia and psychasthenia and symptoms and signs indicative of polyneuropathy, and (c) the differences in the observations made between the two groups with varying degrees of exposure to jet fuel, the authors interpreted the results as indicative of a possible effect of long-term exposure to jet fuel on the nervous system.  相似文献   
93.
94.
The effects of spermidine and spermine at varying concentrations upon the replicative ability of human fibroblasts in cell culture have been studied. The average concentrations of spermidine causing a 50% inhibition of prolifertion (ID50) after 3 days of growth for three normal cell strains and three strains derived from patients with cystic fibrosis (CF) were 4.4 X 10(-6) +/- 1.2 M and 6.2 X 10(-6) +/- 2.1 M, respectively. The values for spermine were 2.0 X 10(-6) +/- 0.5 M for normal and 2.2 X 10(-6) +/- 0.1 M for fibroblasts from cystic fibrosis patients. No significant difference between the replicative ability of normal and CF cell strains was seen over a wide range of polyamine concentrations employed for a period of up to 3 days.  相似文献   
95.
The uni-arterial vascularisation of the lateral bilary duct makes it impossible to systematise the arteries which supply the common bile duct. Only the cystic artery is seen at coelio-mesenteric catheterization. The techniques essential for visualisation of the cystic artery are discussed, on the basis of one hundred coelio-mesenteric arteriograms: frequency of demonstration, origin, course, termination, calibre and length. The frequent finding of opacification of the wall of the gall bladder under normal conditions is stressed.  相似文献   
96.
The in situ microbiota from several aquaculture facilities with active nitrification was examined by transmission electron microscopy of thin sections for the presence of bacteria that contained intracytoplasmic membranes characteristic of the nitrifying bacteria. Colonies of bacteria with the cellular morphology of a species of Nitrosomonas were found to be present in both the culture water and in the biological filter slime of a freshwater chinook salmon (Oncorhynchus tshawytscha) culture system. bacteria in the water possessed the normal nitrosomonas type of ultrastructure, whereas similar bacteria in the slime had an aberrant morphology due to multiple invaginations of the cell wall and cyto-membranes and a significantly greater number of ribosomes. These nitrosomonas-like bacteria lysed during enrichment in commonly used media. Bacteria with the morphology of species of Nitrosomonas and Nitrosococcus were also observed in colonies in the surface slimes of marine culture systems for striped bass (Morone saxatilis) and quahaug (Mercenaria mercenaria).  相似文献   
97.
The per review system for the assessment of research proposals is widely respected by working scientists. Nevertheless two problems associated with the operation of this system by the US National Institutes of Health are identified. First the scientist has no control over which committee will review an application and it may be considered by a quite inappropriate group. Second analysis of the committee composition suggests that in some of the groups several members are not active scientists and therefore not the "peers" of the applicant.  相似文献   
98.
The bioluminescent reaction of adenosine 5'-triphosphate (ATP) with luciferin and luciferase has been used in conjunction with a sensitive photometer (Lab-Line's ATP photometer) to detect significant bacteriuria in urine. This rapid method of screening urine specimens for bacteriuria was evaluated by using 348 urine specimens submitted to the clinical microbiology laboratory at the University of Minnesota Hospitals for routine culture using the calibrated loop-streak plate method. There was 89.4% agreement between the culture method and the ATP assay, with 7.0% false positive and 27.0% false negative results from the ATP assay using 10(5) organisms/ml of urine or greater as positive for significant bacteriuria and less than 10(5) organisms/ml as negative for significant bacteriuria.  相似文献   
99.
The high proportion of seed coat of legume lupins results in big milling lose during kernel flour production, though the seed coat could be value-added as human food. The physicochemical and nutritional properties and antioxidant capacities of seed coats of six Australian sweet lupin cultivars grown at two locations were evaluated. Results showed that genotype, environment and their interaction were significant for seed coat percentage, proximate composition, dietary fibre content, polyphenols and antioxidant capacities. Strong correlations between seed coat lightness and polyphenol content were found. A comparison using multivariate analysis of the seed coat properties showed clear separation based on growing sites. This study indicates the enormous potential of Australian sweet lupin seed coat as an ‘antioxidant dietary fibre’ food source. The results could also benefit to breed varieties with desirable levels of nutrients and phytochemicals.  相似文献   
100.
Commercially available quantum dots have been encapsulated in a poly(methyl methacrylate) film and used as a luminescent downshifting layer on cadmium sulfide/cadmium telluride photovoltaic devices. Application of these films has resulted in a relative improvement to the short‐circuit current of over 4% by I–V measurement, with a significant increase in the contribution of short‐wavelength light resulting in 25% of the current available in this part of the spectrum being captured. The films have been shown to be highly scattering and the associated difficulties this provides to external quantum efficiency measurements have been discussed. A range of optical characterisation techniques, particularly laser beam induced current, have been used to probe the effect the films have on a cadmium sulfide/cadmium telluride device. An alternate methodology for performing external quantum efficiency measurements with the quantum dot films has been proposed. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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