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1.
Declining mortality from smoking in the United States.   总被引:2,自引:0,他引:2  
The proportion of Americans who smoke cigarettes has declined 50% since 1965. The effect on mortality of this considerable reduction has received little attention and is described in this study. U.S. national data were used to enumerate current, former, and never-smokers aged 35 years or older in 1987 and 2002. Mortality rate ratios were used to estimate smoking-attributable deaths among these groups, and corresponding age-adjusted smoking-attributable mortality rates (SAMRs) were calculated. There were 402,000 deaths attributable to smoking in 1987 and 322,000 in 2002. The SAMR for men aged 35 years or more was 556 deaths per 100,000 person-years in 1987, accounting for 24% of all male deaths. By 2002 the SAMR declined 41% to 329 and accounted for only 17% of deaths. The SAMR for women in 1987 was 175, accounting for 12% of deaths. By 2002 the SAMR among women had declined 30% to 122, representing 9% of deaths. The U.S. mortality rate attributable to smoking declined about 35% between 1987 and 2002. The impact of smoking on American society will diminish even further in the foreseeable future as smoking prevalence continues its decline among men and women.  相似文献   

2.
Polychlorinated biphenyl (PCB)-contaminated sediment cores taken from five locations in Lake Hartwell, SC, with an increasing distance from the point source were evaluated for the presence of in situ reductive dechlorination of PCBs on the basis of a comparative congener-specific analysis of PCB distribution profiles between historical (1987) and current (1998) sediments from the same sites. A layer of 1998 sediment that was equivalent to 1987 sediment was determined by direct comparison of total PCB depth profiles after correction for any sedimentation that occurred at each location since 1987. Natural capping of contaminated sediments with the continued deposition of new sediments was observed in all locations except the one farthest from the source area. The residual PCB congeners accumulated in the field samples did not vary from site to site. Certain PCB congeners (e.g., 236-24 + 34-34, 245-25, and 23-4 CB) decreased with time and with depth along with an increase in lower chlorinated PCB congeners in all sampling locations. A similarity in distribution profiles between dechlorinated PCBs in laboratory microcosms and in the field samples was observed. These results provide supporting evidence that in situ reductive dechlorination has occurred in the Twelve Mile Creek arm of Lake Hartwell. Several sediment layers, particularlythe sites with highest PCB concentration, showed similar PCB distribution profiles between 1987 and 1998. An additional change in chlorine distribution between 1987 and 1998 at most "equivalent" depths was not observed. The ortho- and para-substituted congeners that accumulated during dechlorination of Aroclor 1254 after nearly 1 yr of incubation in the laboratory were the prominent residual products in all field samples. At a few locations and depths, evidence for dechlorination at surprisingly low concentrations (1-5 ppm) was observed. These results confirm that in situ reductive dechlorination of PCBs is operating at a very slow rate and may have been at a plateau since 1987 for certain depths and certain locations.  相似文献   

3.
采用大肠杆菌(Escherichia coli)表达海洋弧菌(Vibrio sp.)X511的褐藻胶裂解酶基因,以实现对该酶的大量制备及酶学性质研究。通过序列分析,预测该酶的前20个氨基酸为信号肽,去除信号肽后的蛋白质分子质量约为30 254.28 Da,等电点8.75,分子式为C1368H2100N364O401S6 ,对应的基因序列命名为alg1987。按如下方案构建重组菌:设计特异性核酸引物,PCR扩增得到alg1987;将重组质粒pET-30(a)-alg1987导入大肠杆菌Trans5α进行测序;提取阳性pET-30(a)-alg1987质粒导入大肠杆菌BL21,利用异丙基-β-D-硫代半乳糖苷(IPTG)诱导表达。十二烷基硫酸钠聚丙烯酰胺凝胶电泳(SDS-PAGE)检测诱导后的重组菌胞液上清,发现异源表达的褐藻胶裂解酶分子质量大小与预测值相近。对重组菌中的褐藻胶裂解酶进行表达条件优化,结果显示,最适参数为诱导温度16 ℃,诱导时间16 h,诱导剂IPTG浓度0.8 mmol/L。  相似文献   

4.
本文根据沂水县1987~1994年的研究结果,明确了烟青虫各代为害烟草的时期和田间消长规律,分析了影响烟青虫消长规律的因子。根据1987~1994年的资料采用乏晰因子权重法对烟青虫发生期及发生量的测报进行了验证。  相似文献   

5.
The occurrence of aflatoxins in some common food commodities: wheat, gram and maize flours is reported. Of the total 416 collections during three years (1987-1989) 162 were recorded to be aflatoxin-positive. The incidence of aflatoxins was maximum in the samples of 1987. Most of the contaminated samples contained aflatoxins at levels above 20 micrograms/kg. The environmental conditions and traditional agronomic and storage practices relating to aflatoxin incidence are discussed.  相似文献   

6.
Must and wine from grapes harvested in two vintages (1986 and 1987) were anlyzed during vinification for physicochemical and microbiological characteristics. The 1986 vintage would be considered abnormal or poor vintage because of higher rainfall at harvest, and the 1987 one a normal vintage. Low reducing sugars and high volatile acidity at the beginning of the poor fermentation was observed as compared to normal vinification. The yeast population showed atypical evolution through the process since oxidative yeasts were isolated in the first stages of the poor vinification.  相似文献   

7.
Pinot noir character varies significantly with vintage and with maturity within a given vintage. Our objective was to use a gas chromatography-olfactometry technique (Osme) to compare odor profiles of Pinot noir wines from grapes harvested at different maturities, during 1987 and 1988. Odor profiles of Pinot noir wines from those years were very different from each other with only 4 odor-active peaks common to both vintages. Wines made with grapes harvested at the end of the ripening period had more odor-active peaks than wines from earlier harvested fruit. The 1988 wines had more odor-active peaks than the 1987 wines.  相似文献   

8.
Natural (tritium, 14C, 40K, 226Ra) and man-made radionuclides (90Sr, 134Cs, 137Cs) were determined in soil (top 30 cm), vine leaves, grapes and wine in eight locations of the most important viticultural regions in the Federal Republic of Germany. The results obtained in 1983-1985 have been published previously. Part II of this study presents results obtained in 1986 and 1987, i.e. after the reactor accident at Chernobyl in the Soviet Union. The mean content of 137Cs before (after) Chernobyl was 4 (9) Bq/kg dry matter in soil, 0.07 (3) Bq/kg fresh matter in leaves, 0.02 (0.4) Bq/kg in grapes, and 0.008 (0.9) Bq/L in wine. As compared with 1986, distinctly lower levels were found in leaves, grapes and wine in 1987. In 1986 the content of 134Cs was about half that of 137Cs. Owing to its shorter half-life, 134Cs was below the detection limit in many of the 1987 samples. Transfer factors such as from soil to leaves and from soil to grapes for caesium agreed well in 1983-1985 and 1987, but showed considerable deviations in 1986, due to the ubiquitous contamination of the environment. Results of 90Sr determinations confirmed other reports showing this radionuclide to be a very minor contributor to the total radioactivity released at Chernobyl. No effect of the reactor accident on levels of the other radionuclides was detected.  相似文献   

9.
The specific activity of 137Cs and 90Sr from the global fallout, as well as from the fallout after the reactor accident at Chernobyl, was determined in flour, bran and straw from wheat, rye, barley and oats as well in the corresponding soils (Cambisol). The results show that the activity of 137Cs, but not of 90Sr, in the plant material was considerably higher in 1986, and still to some extent in 1987, compared to 1982. For 137Cs an 90Sr, as well as for most cereal samples, the activity in the bran and straw was significantly higher than in the flour. Determination of stable potassium and calcium in all samples revealed that this enrichment is, to a large extent, the result of a comparable enrichment of these elements in brans and straw. The plant/soil concentration ratios, averaged over all cereals, were for 137Cs (1982 and 1987): flour 0.026 +/- 0.018; bran 0.079 +/- 0.042; straw 0.055 +/- 0.027. For 90Sr (1982, 1986, and 1987): flour 0.19 +/- 0.095; bran 0.70 +/- 0.23; straw 2.35 +/- 0.82.  相似文献   

10.
A total of 205 children were under observation (48 children aged 1.5-3 years in a Baby's Home--spring, 1987; 85 children aged 3-6 years in nurseries with 24-hour stay--spring, 1987; 77 children aged 3-6 years in a Children's Home--spring, 1989). As a result of nutrition reorganization in these institutions vitamin consumption increased due to a more rational selection of food products and the vitamin status of children improved. This was more expressed in vitamin excretion levels, than in the incidence rate of microsymptoms of vitamin deficiency. Additional vitaminization with multivitamin compounds is necessary to eliminate vitamin deficiency in preschool children of isolated institutions.  相似文献   

11.
直链淀粉和总淀粉含量是决定小麦品质的重要指标之一,同时又和小麦的保健功能密切相关,小麦优良品种选育和加工研究都需要快速、简便、微量的测定方法。文中以国标GB7648—1987为基础研究出了一种测定小麦种子中直链淀粉、总淀粉含量的新方法——微量分光光度法(MAS)。直链淀粉含量的测定结果表明,在取样10mg、不脱脂、65℃水浴碱溶12h的情况下,10份小麦样品的组内平行实验误差及与国标法测定结果相比的误差皆<2%,在国标允许的误差范围之内。用可溶性淀粉做标准样品绘制标准曲线,即可同时求得总淀粉含量,组内平行试验误差和与国标法相比的组间误差皆<1%,在国标的允许范围之内。研究结果证明,微量分光光度法具有样品用量少(仅为国标法1/10)、无需样品脱脂、碱溶温度低、环境污染小、省时省力、快捷准确、重复性好、便于样品的批量测定等特点。  相似文献   

12.
Radioactivity in total diet samples (1-day rations of adults) has been determined in the Federal Republic of Germany since 1960. Average intake of cesium-137 was 8.9 Bq per day and per person (Bq/d.p) in 1964, 0.15 in 1985, 4.2 in 1986, 7.2 in 1987, and 2.0 in 1988. Cesium-134, not measureable in pre-Chernobyl fallout, averaged 2.0 Bq/d.p in 1986, 3.0 in 1987, and 0.6 in 1988. Intake of strontium-90 was in the same range as in the years preceding the Chernobyl accident. It is estimated that the total effective equivalent dose for adults due to ingestion of Chernobyl-released radionuclides, including iodine-131, will be 0.14 +/- 0.08 mSv.  相似文献   

13.
Zusammenfassung Die spezifische Aktivität von137CS und90Sr aus dem globalen Fallout sowie aus dem Fallout nach dem Reaktorunfall in Tschernobyl wurde in Mehl, Kleie und Stroh von Weizen, Roggen, Gerste und Hafer sowie in den zugehörigen Böden (Braunerde) bestimmt. Dabei zeigte sich, daß in den Pflanzenproben im Vergleich zu 1982 die Aktivität von137Cs, jedoch nicht von90Sr, im Jahr 1986 erheblich, aber auch 1987 noch deutlich erhöht war. Für137Cs and90Sr sowie für die meisten Getreideproben war die Aktivität in den Kleien and im Stroh deutlich höher als in den Mehlen. Die Bestimmung von stabilem Kalium bzw. Calcium in alien Proben zeigte, daß diese Anreicherung zu einem erheblichen Anteil durch eine analoge Anreicherung dieser Elemente in Kleien und Stroh bedingt ist. Die Boden-Pflanze Transferfaktoren betrugen, gemittelt über alle Getreidearten, für137Cs (1982 und 1987): Mehl 0,026±0,018; Kleie 0,079±0,042; Stroh 0,055±0.027. Für90Sr (1982, 1986 und 1987): Mehl 0,19±0,095; Kleie 0,70±0,23; Stroh 2,35±0,82.
Transfer of137Cs and90Sr to flour, bran and straw from wheat, rye, barley and oats during the years 1982, 1986 (reactor accident at Chernobyl) and 1987 by field measurements
Summary The specific activity of137Cs and90Sr from the global fallout, as well as from the fallout after the reactor accident at Chernobyl, was determined in flour, bran and straw from wheat, rye, barley and oats as well in the corresponding soils (Cambisol). The results show that the activity of137Cs, but not of90Sr, in the plant material was considerably higher in 1986, and still to some extent in 1987, compared to 1982. For137Cs an90Sr, as well as for most cereal samples, the activity in the bran and straw was significantly higher than in the flour. Determination of stable potassium and calcium in all samples revealed that this enrichment is, to a large extent, the result of a comparable enrichment of these elements in brans and straw. The plant/soil concentration ratios, averaged over all cereals, were for137CS (1982 and 1987): flour 0.026±0.018; bran 0.079±0.042; straw 0.055±0.027. For90Sr (1982, 1986, and 1987): flour 0.19±0.095; bran 0.70±0.23; straw 2. 35±0.82.
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14.
Analytical values for α-acid content, as measured by lead conductance value, of twelve varieties of hops from the 1987 crop are presented in relation to the district of production. Satisfactory variabilities have been achieved by Fuggle, Progress, Bramling Cross, Northern Brewer, Zenith, Wye Challenger and Omega. Wye Northdown has increased in variability, reaching the upper limit of acceptability despite an increase in sampling rate. Goldings, W.G.V. and Wye Target have continued to show higher than normal variabilities. This year Yeoman has moved in variability above the acceptable limit. The sampling rates have been considered and in view of the unusual growing conditions experienced with the 1987 crop, with hop yields considerably reduced and α-acids increased to very high levels, no changes have been recommended.  相似文献   

15.
Zusammenfassung Natürliche (Tritium,14C,40K,226Ra) und künstliche Radionuklide (90Sr,134Cs,137Cs) wurden in Boden (oberste 30 cm), Weinblättern, Trauben und Wein von 8 Standorten in den wichtigsten deutschen Weinanbaugebieten bestimmt. Ergebnisse der Jahre 1983–1985 wurden bereits veröffentlicht. Im vorliegenden Teil II wird über Ergebnisse aus den Jahren 1986 und 1987, d. h. über Auswirkungen des Reaktorunfalls von Tschernobyl, berichtet. Mittlere137Cs-Gehalte betrugen vor Tschernobyl (nach Tschernobyl) im Boden 4 (9) Bq/kg TM, in Blättern 0,07 (3) Bq/kg FM, in Trauben 0,02 (0,4) Bq/kg FM, im Wein 0,008 (0,9) Bq/L. Im Erntegut 1987 war ein deutlicher Rückgang gegenüber 1986 festzustellen. Die134Cs-Gehalte lagen 1986 etwa bei der Hälfte der137Cs-Gehalte. Auf Grund der kürzeren Halbwertszeit des134Cs erreichte dieses 1987 in vielen Proben nicht mehr die Nachweisgrenze. Während die an Proben der Jahre 1983–1985 und 1987 ermittelten Transferfaktoren Boden-Blatt und Boden-Traube für Cäsium gut übereinstimmten, verursachte die 1986 übiquitär vorhandene Radiocäsiumkontamination in diesem Jahr erhebliche Abweichungen. Ergebnisse der90Sr-Bestimmungen bestätigten, daß dieses einen sehr geringen Anteil des in Tschernobyl freigesetzten Radionuklidgemisches darstellte. Auswirkungen des Reaktorunfalls auf die Gehalte der sonstigen Radionuklide konnten nicht festgestellt werden.
Radioecology of the vine Part 2. Effects of the reactor accident at Chernobyl on radioactivity in soil, leaves, grapes, and wine
Summary Natural (tritium,14C,40K,226Ra) and manmade radionuclides (90Sr,134Cs,137Cs) were determined in soil (top 30 cm), vine leaves, grapes and wine in eight locations of the most important viticultural regions in the Federal Republic of Germany. The results obtained in 1983–1985 have been published previously. Part II of this study presents results obtained in 1986 and 1987, i.e. after the reactor accident at Chernobyl in the Soviet Union. The mean content of137Cs before (after) Chernobyl was 4 (9) Bq/kg dry matter in soil, 0.07 (3) Bq/kg fresh matter in leaves, 0.02 (0.4) Bq/kg in grapes, and 0.008 (0.9) Bq/L in wine. As compared with 1986, distinctly lower levels were found in leaves, grapes and wine in 1987. In 1986 the content of134Cs was about half that of137Cs. Owing to its shorter half-life,134Cs was below the detection limit in many of the 1987 samples. Transfer factors such as from soil to leaves and from soil to grapes for caesium agreed well in 1983–1985 and 1987, but showed considerable deviations in 1986, due to the ubiquitous contamination of the environment. Results of90Sr determinations confirmed other reports showing this radionuclide to be a very minor contributor to the total radioactivity released at Chernobyl. No effect of the reactor accident on levels of the other radionuclides was detected.
  相似文献   

16.
Four sediment cores were collected from Lake Hartwell, SC, in 1987 and 1998 and analyzed for polychlorinated biphenyl (PCB) congeners. Total PCBs ranged from -0 to 58 microg/ g. Positive matrix factorization (PMF) was applied to the data sets to determine PCB source profiles. Two factors were determined for each data set. One factor resembled the original estimated PCB mixture of 80% Aroclor 1016 and 20% Aroclor 1254 and the other factor was a dechlorinated version of the mixture. Evidence of a dechlorination plateau is apparent from the PMF loading solutions because the dechlorinated congener profiles do not change from 1987 to 1998, butthe contribution to the profile from the dechlorinated factor increases from 73% (1987) to 87% (1998). PMF source contributions and plots of PCB concentration versus congener for individual samples provide evidence of enhanced dechlorination at high concentrations. After source apportionment an anaerobic dechlorination model was applied to the dechlorinated source profiles to quantify possible dechlorination pathways. It was found that dechlorination process M, extended to target biphenyl rings with up to six chlorines, provided the best fit for an individual process, and M + Q provides the best fit for combined processes, although M + LP also provides a similarfit. Process LP targets the higher chlorinated congeners and appears to dechlorinate PCBs in the sediments initially.  相似文献   

17.
King P 《Food management》1991,26(3):112-5, 118, 120
The Omnibus Budget Reconcilitation Act of 1987 contains sweeping changes in nursing home regulations aimed at improving residents' quality of life. However, implementing these rules in today's economy has operators of even well-managed nursing homes worried. Here's why.  相似文献   

18.
Summary Zweigelt 1987, a typical Austrian wine treated with wine additives such as sulphur dioxide,l-ascorbic acid and sorbic acid was stored for 77 days. All characteristic wine components were analysed during the storage period. Only changes in colour could be detected. The changes in the amount of anthocyanins and anthocyanidin chlorides were analysed. The results show that Zweigelt 1987 mixed with wine additives such asl-ascorbic acid or sorbic acid resulted in a larger loss in colour than untreated wine. The changes could be measured photometrically but they were invisible to the naked eye. Appropriate use of wine additives did not appear to deterioriate the ruby colour of young red wine during the period tested.
Der Einfluß von Wein-Zusatzstoffen auf Farbe und Farbqualität von jungem Rotwein
Zusammenfassung Österreichischer Wein Zweigelt 1987, welcher für die Versuchsreihe unter authentischen Bedingungen hergestellt worden war, wurde mit Weinbehandlungsmitteln wie Schwefeldioxid, Sorbinsäure undl-Ascorbinsäure versetzt. Die Wechselwirkungen der Farbe des Rotweines mit den zugesetzten Chemikalien wurden während einer Lagerzeit von 77 Tagen studiert. Die Anthocyane und Anthocyanidinchloridmengen wurden bestimmt. Die Ergebnisse zeigen, daß Zweigelt 1987, der mitl-Ascorbinsäure bzw. Sorbinsäure versetzt worden war, etwas größere Farbverluste zeigte als unbehandelter Wein. Abschließend wurde festgestellt, daß die Farbveränderungen zwar photometrisch meßbar sind, aber mit freiem Auge nicht erkannt werden. Eine Verwendung dieser Weinbehandlungsmittel in richtiger Dosierung führt zu keiner Verschlechterung der Farbqualität bei jungem Rotwein über den untersuchten Zeitraum.
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19.
Summary Bavarian cereals and wheat flour from the 1987 harvest were analysed for nivalenol (NIV) and deoxynivalenol (DON) using high performance liquid chromatography (HPLC) and for T-2 toxin and zearalenone (ZEA) by enzyme-linked-immunosorbent as say (ELISA). The study included 190 field samples of wheat, barley, rye and oat with visibly damaged ears, 45 samples of wheat intended for feed production and two series of wheat flour (type 550) and whole wheat flour collected in October 1987 and June 1988. The field samples examined showed a high DON contamination of wheat (87%) with an average of 3.96 mg/kg and a maximum of 43.8 mg/kg. Mean levels between 0.33 mg/kg and 0.27 mg/kg DON could be detected in barley, rye and oat. Of the wheat samples, 58% contained ZEA with a maximum of 1.560 mg/kg. The highest levels of ZEA were detected in samples which also showed high concentrations of DON. The NIV and T-2 toxin levels were comparatively low. Thirty percent of the samples showed NIV concentrations between 0.04 mg/kg and 0.29 mg/kg and 38% contained between 0.005 and 0.60 mg/kg of T-2. In the wheat samples for feed production, only DON was detected with an average of 0.190 mg/kg and a maximum of 0.75 mg/kg. The highest DON levels (0.58 mg/kg) from October 1987 were found in the wheat flour samples which were lower than the highest DON concentration (3.24 mg/kg) detected in the samples collected during June 1988. This fact was probably due to a substantial amount of non-contaminated wheat from 1986. The toxin concentrations in the whole wheat flour were not higher than in the type 550 flour. The regional distribution of the mean DON concentrations showed the highest levels in Middle and Lower-Franconia.
Vorkommen von Fusarium Mykotoxinen in bayerischem Getreide der Ernte 1987
Zusammenfassung Cerealien und Weizenmehle der bayerischen Ernte 1987 wurden mittels hochauflösender Flüssigchromatographie (HPLC) auf Nivalenol (NIV) und Deoxynivalenol (DON) Bowie mit Enzymimmunoassay auf T-2 Toxin und Zearalenon (ZEA) analysiert. Die Untersuchungen umfaßten 190 Feldproben von Weizen, Gerste, Roggen und Hafer, die alle optisch erkennbaren Fusarienbefall aufwiesen, 45 Futterweizenproben Bowie zwei Probenserien von Weizenmehlen der Type 550 und Vollkornweizenmehlen, die im October 1987 und im Juni 1988 gezogenwurden. — Die Untersuchungen der Feldproben ergaben eine hohe DON-Kontamination des Weizens (87%) mit einem durchschnittlichen Gehalt von 3,96 mg/kg und einem Maximalgehalt von 43,8 mg/kg. In Gerste, Roggen und Hafer konnten durchschnittlich zwischen 0,33 mg/kg und 0,27 mg/kg DON-nachgewiesen werden. 58% der Winterweizenproben wiesen Zearalenon mit einem Maximalgehalt von 1,56 mg/kg auf. Die höchsten ZEA-Werte wurden in Proben ermittelt, die gleichzeitig einen hohen DON-Gehalt aufwiesen. Die Konzentrationen von NIV und T-2 Toxin waren vergleichsweise niedrig. 30% der Proben hatten NIV-Gehalte zwischen 0,04 mg/kg und 0,29 mg/kg und 38% enthielten T-2 Toxin zwischen 0,005 mg/kg und 0,06 mg/kg. In den Futterweizenproben konnte DON als einziges Toxin mit einem Gehalt von durchschnittlich 0,19 mg/kg und maximal 0,75 mg/kg festgestellt werden. Die Weizenmehle, die im October 1987 gezogen wurden, wiesen maximal 0,58 mg/kg DON auf. Die Gehalte lagen damit medriger als die der Mehlproben vom Juni 1988, die maximal 3,24 mg/kg und durchschnittlich 0,26 mg/kg DON enthielten. Dieser Sachverhalt könnte auf Anteile von nicht kontaminiertem Weizen der Ernte 86 an den im October gezogenen Mehlproben zurückgeführt werden. Die Toxingehalte der Vollkornmehle waren nicht höher als die der Weizenmehle der Type 550. Die höchsten Durchschnittsgehalte von DON wurden in Mittel- und Unterfranken festgestellt.
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20.
The following article is an edited version of the presentation given by Dr John Gilbert Davis, founder member of the Society, to the Reading Branch of the London, South and Eastern Section at the University of Reading on 12 March 1987.  相似文献   

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