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81.
N. M. Durakbasa ÖVE P. H. Osanna ÖVE 《e & i Elektrotechnik und Informationstechnik》1998,115(4):207-212
Inspection, measuring and testing instruments are influencing the quality in modern production. Therefore the confirmation of this equipment is an essential quality requirement for the entire production especially at the increasing demands of micro and nanotechnology. Thereby the large expense of the confirmation can be reduced essentially through computer assistance. For this purpose a special method has been developed at the Department for Interchangeable Manufacturing and Industrial Metrology, with which an increase of the flexibility level and efficiency of a system for the management and confirmation of the inspection, measuring and test equipment can be achieved. 相似文献
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Choline acetyltransferase catalyzes the synthesis of acetylcholine from choline and acetylcoenzyme A (ACoA) in both nervous and non-nervous tissues. Carnitine acetyltransferase occurs in several tissues and transfers acetyl groups from ACoA to carnitine forming acetylcarnitine and exhibits weak choline acetyltransferase activity. Several haloacetylcholines and haloacetylcarnitines were synthesized to develop selective inhibitors of choline acetyltransferase and carnitine acetyltransferase. Acetylcholine is a transmitter for some presynaptic neurons and/or amacrine cells in retina. Selective inhibitors of choline acetyltransferase and carnitine acetyltransferase were used in the evaluation of choline acetyltransferase and carnitine acetyltransferase activities in the rat retina. Choline acetyltransferase and carnitine acetyltransferase activities were assayed by transferring of [14C]acetyl group from [14C]ACoA to choline or carnitine and estimating [14C]-acetylcholine or [14C]acetylcarnitine. This study gave the following results: (a) Bromoacetylcholine (BrACh) was a selective inhibitor of purified choline acetyltransferase (I50, 2.2 microM); (b) (R)-bromoacetylcarnitine [(R)-BrACa] was more potent for inhibiting purified carnitine acetyltransferase (I50, 4 microM) than purified choline acetyltransferase (I50, 46 microM); (c) Rat retinal sonicate gave choline acetyltransferase activity of 98 +/- 6 nmol of ACh formed/mg/10 min. When the carnitine acetyltransferase was completely inhibited by (R)-BrACa, the activity for choline acetyltransferase decreased to 47 +/- 1 nmol, and this decrease was possibly due to the formation of some [14C]acetylcholine by carnitine acetyltransferase. The net retinal choline acetyltransferase activity was 51 nmol acetylcholine/mg protein/10 min; (d) Rat retinal sonicate contained carnitine acetyltransferase activity of 102 +/- 7 nmol acetylcarnitine formed/mg protein/10 min. This was not altered by inhibition of choline acetyltransferase with BrACh. This means that choline acetyltransferase did not use carnitine as a substrate. Choline acetyltransferase and carnitine acetyltransferase activities did not change after dialysis of retinal sonicates at 4 degrees C for 24 hrs. These observations suggest that BrACh and (R)-BrACa are useful for assessing the correct values for choline acetyltransferase and carnitine acetyltransferase activities in retinal tissues. 相似文献
85.
NE Sokolova UM Malikov VL Kuznetsov NA Emel''yanov 《Canadian Metallurgical Quarterly》1998,28(5):500-503
OBJECTIVE: An attempt was made to find out how many operations were performed in Europe in 1995 for congenital heart disease. METHODS: Representatives from the 20 most active European countries which could supply reliable information were contacted. They were asked to contact all surgeons performing significant numbers of operations for congenital heart disease in their country. The numbers of operations on children under and over 1 year operated on with and without cardiopulmonary bypass were collected. No attempt was made to collect more detailed information such as operative mortality as it was felt that many surgeons would be reluctant to give their results and the data would be incomplete. RESULTS: A total of 27,976 operations were recorded, of which 20,318 were performed with cardiopulmonary bypass and 7658 without. The total population of the 20 European countries was 448 million and the mean number of operations performed with cardiopulmonary bypass per million was 45.4. However, the rate varied from 9.1 to 70.1. The percentage of operations on cardiopulmonary bypass performed in the first year of life varied from 9.4% to 44.4%. CONCLUSIONS: The total of nearly 28,000 operations in 1995 is probably an underestimate, but it has been difficult to collect this data at all. Obviously many smaller countries have not been included, and some older patients undergoing operations such as atrial septal defect closure in adult units have been missed. The number of open heart operations per million vary in different countries and this presumably represents differing referral patterns. If their numbers are low in some countries, these results may be helpful in persuading their governments that more resources are needed for congenital heart surgery. It is also interesting to see the variation in the number of operations performed in the first year of life. Those countries with a lower rate may have a backlog of older patients who were previously palliated, or their surgeons may still prefer initial palliation and later correction in some conditions rather than early correction. It is hoped that with better prospective data collection, an assessment can be repeated in 2000. 相似文献
86.
The investigations of authors concerning infants and their families were generalized on the basis of the observations of infants and their parents with some psychological problems in families. The principles of psychotherapeutic work in above-mentioned groups were formulated. Besides the methods of the diagnosis of psychical deviations development in first year infants as well as peculiarities of alterations in mother-baby system and the main forms of psychic disturbances correction in infants were also described. 相似文献
87.
VE Sahini M Dumitrescu E Volanschi L Birla C Diaconu 《Canadian Metallurgical Quarterly》1996,58(3):245-253
Neurones in the ureterovesical ganglion complex provide autonomic innervation to the pelvic ureter, the ureterovesical junction and the bladder trigone. We examined the distribution and peptide co-expression pattern of nitric oxide synthase (NOS) in the human ureterovesical ganglia by combining NADPH-diaphorase histochemistry with immunoreactivity for vasoactive intestinal peptide (VIP), neuropeptide Y (NPY), and calcitonin gene-related peptide (CGRP). Less than 20% of nerve cells in the large ganglia of the ureterovesical complex were stained for NOS activity. In elderly individuals, ganglion cells regularly exhibited conspicuous morphological alterations suggestive of degenerative changes. Most of the NOS-positive cell bodies costained for VIP-immunoreactivity. A minority of NOS-expressing cells also reacted for NPY-immunoreactivity. CGRP-immunoreactivity was present in varicose terminal-like nerve fibres which were found to encircle NOS-containing perikarya. Occasionally, NOS-positive somata were surrounded by plexiform axon terminals which immunostained for VIP or NPY. We conclude that the passage of urine across the ureterovesical junction is under relaxatory control of a local nitric oxide/VIP(NPY) pathway which may be modulated by preganglionic efferent and/or primary afferent input. 相似文献
88.
VA Tyurin YY Tyurina PJ Quinn NF Schor R Balachandran BW Day VE Kagan 《Canadian Metallurgical Quarterly》1998,60(2):270-281
Incubation of mock-transfected PC12 rat pheochromocytoma cells (PC12) for 2 h with increasing concentrations of glutamate caused progressive loss of viability (e.g., 67% with 15 mM glutamate). In contrast, the viability of bcl-2-transfected cells (PC12/bcl-2) was unaffected by glutamate. Neither PC12 nor PC12/bcl-2 cells showed a significant incidence of apoptosis in response to glutamate. Conventional phospholipid analysis by high-performance TLC and phosphorous determination showed no significant changes in the phospholipid composition of either cell line incubated with =15 mM glutamate. Phospholipid peroxidation was quantified in the cells using our newly developed method based on fluorescence-HPLC analysis of metabolically incorporated oxidation-sensitive and fluorescent fatty acid, cis-parinaric acid. Unlike previous studies that measured total phospholipid oxidation, this novel technology permitted quantitation of oxidative stress in different classes of labeled phospholipids (the amount of labeled phospholipids in the cells did not exceed 1% of total phospholipids). Significant peroxidation of phosphatidylcholine and phosphatidylethanolamine occurred in PC12 cells treated with >5 mM glutamate. The peroxyl radical initiator 2,2'-azobis(2,4-dimethylvaleronitrile) caused a pronounced loss of all major phospholipid classes in PC12 cells, but no loss of cell viability. No phospholipid peroxidation was detected in PC12/bcl-2 cells incubated with =15 mM glutamate or with 2, 2'-azobis(2,4-dimethylvaleronitrile). These results directly demonstrate that peroxidation of membrane phospholipids is not responsible for the cytotoxicity of glutamate in PC12 cells. Total cellular thiol, protein thiol and GSH reserves were quantified by a previously described electron paramagnetic resonance spectrometric method. Total thiols were ca. 1.5-fold greater in PC12/bcl-2 than in PC12 cells. Glutamate (=5 mM) caused a progressive and equally significant decrease in total thiols and GSH in both PC12 and PC12/bcl-2 cells. High glutamate concentrations caused oxidation of protein sulfhydryls in PC12 cells, but not in PC12/bcl-2 cells. The results suggest that the changes in cellular milieu caused by bcl-2 gene transfection protect PC12 cells from the toxic effects of glutamate in a manner consistent with prevention of protein sulfhydryl oxidation. 相似文献
89.
90.
GM Tozer VE Prise R Motterlini BA Poole J Wilson DJ Chaplin 《Canadian Metallurgical Quarterly》1998,42(4):849-853
The present study was undertaken to analyse the loss of heterozygosity (LOH) of the three genes, BRCA1, BRCA2 and ATM, and their correlation to clinicopathological parameters in sporadic breast cancer. We studied 59 sets of invasive ductal carcinoma, compared to matched normal control DNA. Microsatellite markers intragenic to BRCA1 (D17S1323, D17S1322, D17S855), BRCA2 (D13S1699, D13S1701, D13S1695) and ATM (D11S2179) were simultaneously used. In addition, one marker telomeric to BRCA2 (D13S1694) and four markers flanking ATM were analysed (D11S1816, D11S1819, D11S1294, D11S1818). Thirty-one per cent of the informative cases showed loss of heterozygosity for the BRCA1 gene, 22.8% for BRCA2 gene and 40% for ATM. LOH of BRCA1 correlated with high grade tumors (p=0.0005) and negative hormone receptors (p=0.01). LOH of ATM correlated with higher grade (p=0.03) and a younger age at diagnosis (p=0.03) in our set of tumors. No correlations were detected between BRCA2 LOH and any of the analysed clinicopathological parameters. However, a correlation was detected between allelic loss of the D13S1694 marker, telomeric to BRCA2, and larger tumor sizes and negative estrogen receptors, favoring the hypothesis of the presence of another putative tumor suppressor gene, telomeric to BRCA2, in the 13q12-q14 region. Only 11 tumors had LOH at more than one of the three genes, most of them (6/11) associated LOH of BRCA1 and ATM. One tumor only combined loss of the three genes BRCA1, BRCA2 and ATM. 相似文献