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11.
12.
A yearly pattern in the occurrence of uterine cervical cancer (UCC), obtained from cytological examinations reported as type V (cases concluding a malignant alteration), has been previously shown for data obtained in the Monterrey Metropolitan Area (state of Nuevo Leon, Mexico) for a span of 10 years (1978-1987), with a peak of relative incidence in the month of February being high stable for consecutive years. With the aim of extending and validating those results, we analyzed the monthly totals of positive detected cases of UCC in the states of Nuevo Leon, Chihuahua, Coahuila, and Tamaulipas (covering most of Northern Mexico) during the same period. To eliminate bias due to the seasonal variation in the number of screening smears, data were first expressed in relation to the number of cytological examinations done the same month. The least-squares fit of a 1-year cosine curve to the data of relative incidence in the four states reveals a statistically significant yearly pattern (p = .008), with a maximum of relative incidence in February almost double that during the rest of the year. Results indicate that the relative incidence of UCC is higher than the yearly average during the winter, with secondary peaks in May and October. In view of the nonsinusoidal waveform in the incidence of UCC, we undertook a multiple-component analysis, allowing several cosine functions to be simultaneously fitted to the data. Results indicate that the yearly pattern in the relative incidence of UCC can be represented by a model that includes two components with periods of 12 and 4 months (p = .004). The same model can be documented as statistically significant independently for each of the four states. These results, summarizing over 2200 positive cases of UCC detected in more than 1,100,000 screening smears, are in full agreement with those found previously for part of the state of Nuevo Leon and reveal a highly stable and predictable yearly pattern of variation in the relative incidence of UCC in Northern Mexico. 相似文献
13.
Klaus Fröhlich Öve Gerfried Zeichen 《e & i Elektrotechnik und Informationstechnik》1998,115(4):226-226
Ohne Zusammenfassung 相似文献
14.
L Fr?yland DK Asiedu H Vaagenes A Garras O Lie GK Totland RK Berge 《Canadian Metallurgical Quarterly》1995,36(12):2529-2540
The mechanism behind the hypolipidemic effect of tetradecylthioacetic acid (CMTTD, a non-beta-oxidizable 3-thia fatty acid) was studied in hamsters fed a high cholesterol diet (2%), which resulted in hyperlipidemia. Treating hyperlipidemic hamsters with CMTTD resulted in a progressive hypocholesterolemic and hypotriacylglycerolemic effect. Decreased plasma cholesterol was followed by a 39% and 30% reduction in VLDL-cholesterol and LDL-cholesterol, respectively. In contrast, the HDL-cholesterol content was not affected, thus decreasing the VLDL-cholesterol/HDL-cholesterol and LDL-cholesterol/HDL-cholesterol ratios. 3-Hydroxy-3-methylglutaryl- (HMG) CoA reductase activity and its mRNA level were unchanged after CMTTD administration. Also, the LDL receptor and LDL receptor-related protein (LRP-4) mRNAs were unchanged. The decrease in plasma triacylglycerol was accompanied by a 45% and 56% reduction in VLDL-triacylglycerol and LDL-triacylglycerol, respectively. The hypolipidemic effect of CMTTD was followed by a 1.4-fold increase in mitochondrial fatty acid oxidation and a 2.3-fold increase in peroxisomal fatty acid oxidation. CMTTD treatment led to an accumulation of dihomo-gamma-linolenic acid (20:3n-6) in liver, plasma, very low density lipoprotein, and heart. Noteworthy, CMTTD accumulated more in the heart, plasma, and VLDL particles compared to the liver, and in the VLDL particle alpha-linolenic acid (18:3n-3) decreased whereas eicosatetraenoic acid (20:4n-3) increased. In addition, linoleic acid (18:2n-6) and the total amount of polyunsaturated fatty acids decreased, the latter mainly due to a decrease in n-6 fatty acids. The present data show that CMTTD was detected in plasma and incorporated into VLDL, liver, and heart. The relative incorporation (mol%) of CMTTD was heart > VLDL > liver. In conclusion, CMTTD causes both a hypocholesterolemic and hypotriacylglycerolemic effect in hyperlipidemic hamsters. 相似文献
15.
Maurus Biedermann Konrad Grob Dieter Fr?hlich Werner Meier 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1992,195(5):409-416
Summary On-line coupled liquid chromatography-gas chromatography-flame ionisation detection (LC-GC-FID) enables efficient and unambiguous determination of irradiation for some fat-containing foods (e.g. meat). Other products, however, contain interfering components or are contaminated, e.g., with mineral oil. Since more selective detection by mass spectrometry has limited success, the determination was improved by a more selective isolation of some key components among the fat degradation products, e.g. the dienes or trienes, by LC-LC-GC-FID. Applications are shown for soup mixes, some spices, fish, and shrimps.
Nachweis der Bestrahlung fetthaltiger Lebensmittel durch direkt gekoppelte LC-GC und LC-LC-GC
Zusammenfassung Die Bestrahlung einiger fetthaltiger Lebensmittel, z. B. Fleisch, kann mit direkt gekoppelter LC-GC-FID rationell und eindeutig nachgewiesen werden. In anderen Proben wird die Analyse aber durch Inhaltsstoffe des Produktes oder durch Verunreinigungen (z. B. mit Mineralöl) gestört. Da selektivere Detektion durch Massenspektrqmetrie wenig verspricht, wurde der Nachweis durch selektivere Isolierung von Schlüsselkomponenten unter den Bestrahlungsprodukten, z. B. der Diene oder Triene, mittels LC-LC-GC yerbessert. Anwendungen werden gezeigt für Suppenpulver, einige Gewürze, Fisch und Garnelen.相似文献
16.
B Quinting JM Reyrat D Monnaie G Amicosante V Pelicic B Gicquel JM Frère M Galleni 《Canadian Metallurgical Quarterly》1997,406(3):275-278
Changes in motor function were assessed in male rats after injecting graded doses (100, 200, 400, and 800 mg/kg, IP) of ammonium chloride and ammonium acetate. The effects were correlated with the concentrations of ammonia and glucose in the brain and blood. Spontaneous motor activity and motor coordination were inhibited after injecting 100 and 200 mg/kg, whereas with 400 and 800 mg/kg the animals exhibited convulsive movements. A dose-dependent increase was found in the concentrations of ammonia and glucose in both blood and brain. These were restored, 25 min after treatment, to control levels in the blood and not in the brain. A correlation was found between the time courses of inhibitory motor events and a rise in brain ammonia levels. Convulsant action of ammonium salts was accompanied by a marked elevation of ammonia and glucose concentration in the brain. The findings suggest that detoxication of diffused ammonia is a rate-limiting process in the brain and that ammonia, at toxic concentrations, decreases glucose utilization in the brain, resulting in an inhibition of motor function. A very high concentration of ammonia in the brain, although inhibiting glucose utilization, produces clonic convulsions probably by activating directly the motor neurons. 相似文献
17.
Frédéric Debode Eric Janssen Gilbert Berben 《European Food Research and Technology》2007,226(1-2):273-280
In this paper, four different physical treatments (microwaves, heating by conduction, sonication and pressure autoclaving)
were performed to degrade a pure DNA extract, and their influence on GMO quantification was studied. The aim was to check
the hypothesis that processing of agrofood products results in a similar degradation rate for both the transgenic target and
the specific target. Indeed we could observe that even if the used physical treatments could lead to a significant increase
of C
t values for both transgenic and specific targets, the resulting ΔC
t remained stable. So, the main conclusion of the study is that the aforementioned hypothesis seems valid and thus a physical
degradation of DNA will not affect the relative quantitation of the GMO content, provided that both the specific and transgenic
targets have very similar size. A second important issue of the experiments performed was that DNA is a very robust molecule
as it is extremely difficult to reach a mean size below 100 bp. The study also gives evidence of the importance of using small
targets. 相似文献
18.
K. Fröhlich 《e & i Elektrotechnik und Informationstechnik》2002,119(1):15-21
It is discussed to what extent tools, provided by modern information technology, reasonably improve the performance of high voltage circuit breakers in transmission systems of electric power. Controlled switching, properly applied, has a high potential to increase life expectancy of the breaker itself and of the adjacent equipment. Power quality can also be improved. The technical advantage of controlled switching is beyond doubt, although the economic benefits are not easily quantified. In terms of breaker intelligence, another very important aspect is condition diagnosis. In particular a model based diagnosis seems to point to the future. Condition diagnosis giving maintainance requirements and pre-warning of impending failures should facilitate the tasks of the operating personnel. As a conclusion it can be stated that more intelligence of circuit breakers would be useful. 相似文献
19.
Floccia Caroline; Goslin Jeremy; Girard Frédérique; Konopczynski Gabrielle 《Canadian Metallurgical Quarterly》2006,32(5):1276
The processing costs involved in regional accent normalization were evaluated by measuring differences in lexical decision latencies for targets placed at the end of sentences with different French regional accents. Over a series of 6 experiments, the authors examined the time course of comprehension disruption by manipulating the duration and presentation conditions of accented speech. Taken together, the findings of these experiments indicate that regional accent normalization involves a short-term adjustment mechanism that develops as a certain amount of accented signal is available, resulting in a temporary perturbation in speech processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
20.
De Fruyt Filip; Van Leeuwen Karla; Bagby R. Michael; Rolland Jean-Pierre; Rouillon Frédéric 《Canadian Metallurgical Quarterly》2006,18(1):71
Structural, mean- and individual-level, differential, and ipsative personality continuity were examined in 599 patients treated for major depression assigned to 1 of 6 forms of a 6-month pharmaco-psychotherapy program. Covariation among traits from the Five Factor model remained invariant across treatment, and patients described themselves as slightly more extraverted, open to experience, agreeable and conscientious, and substantially more emotional stable after treatment. Trait changes were only to a small extent explained by changes in depression severity. There was evidence for differential, individual-level, and ipsative stability, with stable personality profiles in terms of shape and to a lesser extent in terms of scatter and elevation. Traits remain relatively stable, except for emotional stability, despite the depressive state and the psychopharmacological interventions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献