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31.
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Data from the Cancer Registry of Slovenia were used in a cohort study to determine whether the incidence of second primary cancers in patients with first primary breast cancer differs from the incidence expected in the general population. Special interest was given to long-term survivors. The expected numbers of second primary cancers were calculated by multiplying the number of appropriate person-years at risk by the corresponding age- and calendar-period-specific cancer incidence rates for women in Slovenia. The risk of a second primary cancer was expressed as the standardized incidence ratio (SIR). Of the 8,917 patients newly diagnosed in the period 1961-85 and followed-up to the end of 1994, 547 (6.2 percent) developed second primary cancers, whereas 410 (4.7 percent) were expected (SIR = 1.3, 95 percent confidence interval [CI] = 1.2-1.4). The risk was higher among younger patients. In long-term survivors, the risk was increased significantly for second primary cancer of the breast (SIR = 1.4, CI = 1.1-1.7), lung cancer (SIR = 1.6, CI = 1.1-2.3), melanoma (SIR = 2.7, CI = 1.5-4.4) and non-melanoma skin cancers(SIR = 2.0, CI = 1.6-2.4), corpus uteri cancer(SIR = 1.6, CI = 1.2-2.1), ovarian cancer(SIR = 2.3, CI = 1.7-3.0), and thyroid cancer (SIR = 2.5, CI = 1.2-4.6). Our results confirm the findings of several cohort studies carried out in Europe, the United States, and Japan, indicating that breast cancer patients should be monitored carefully for the occurrence of second primary cancers. 相似文献
33.
R.B. Pearson 《Food chemistry》1982,8(2):85-96
Manufacture of polyvinyl chloride (PVC) in western Europe for all applications is now almost 4 m tonnes and the UK accounts for about 400 kt of this.The aim of this paper is to illustrate the relative importance of PVC as a packaging material where, in the UK for example, for food packaging it accounts for almost 40 kt (10%) of the PVC used.The different types of PVC packaging material—bottles, foil, cling film and cap sealing—and their method of manufacture are described, together with the range of food packaging applications in which they are used. The physical properties of PVC are described and, additionally, its cost and competitiveness with other materials are compared. The chemical nature of PVC compositions arising from the addition of heat stabilisers and plasticisers to achieve the desired properties is also described, with particular reference to heat stability.With the VCM toxicity issue now behind us, and PVC polymer with a maximum level of 1 ppm vinyl chloride monomer (VCM) being supplied for food packaging, PVC must be the most stringently controlled and thoroughly researched material for food packaging. Recent developments in polymerisation technology and polymer manufacture, which have enabled this level to be achieved, are briefly described.The current situation on the global migration issue, on which attention is currently focused, not only for plasticised PVC, but also other packaging materials as well, is briefly reviewed. 相似文献
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MJ Prado AL Nicastri PL Costa T Rockman IL Tersariol HB Nader RT Barros EB Prado 《Canadian Metallurgical Quarterly》1997,30(7):865-872
The aim of the present study was to evaluate renal and liver distribution of two monoclonal immunoglobulin light chains. The chains were purified individually from the urine of patients with multiple myeloma and characterized as lambda light chains with a molecular mass of 28 kDa. They were named BJg (high amount of galactose residues exposed) and BJs (sialic acid residues exposed) on the basis of carbohydrate content. A scintigraphic study was performed on male Wistar rats weighing 250 g for 60 min after i.v. administration of 1 mg of each protein (7.4 MBq), as the intact proteins and also after carbohydrate oxidation. Images were obtained with a Siemens gamma camera with a high-resolution collimator and processed with a MicroDelta system. Hepatic and renal distribution were established and are reported as percent of injected dose. Liver uptake of BJg was significantly higher than liver uptake of BJs (94.3 vs 81.4%) (P < 0.05). This contributed to its greater removal from the intravascular compartment, and consequently lower kidney accumulation of BJg in comparison to BJs (5.7 vs 18.6%) (P < 0.05). After carbohydrate oxidation, there was a decrease in hepatic accumulation of both proteins and consequently a higher renal overload. The tissue distribution of periodate-treated BJg was similar to that of native BJs: 82.7 vs 81.4% in the liver and 17.3 vs 18.6% in the kidneys. These observations indicate the important role of sugar residues of Bence Jones proteins for their recognition by specific membrane receptors, which leads to differential tissue accumulation and possible toxicity. 相似文献
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Heritabilities were estimated for lactation average log, base 2, somatic cell count from cows with four or more tests in each lactation. Estimates were for first, second, and third or later parities (defined by age at calving) individually and for mixed parities. Estimates were from sire components of variance with numbers of sires and daughters of 406 and 22,140; 337 and 8,659; 311 and 6,122; and 310 and 10,217 for mixed, first, second, and third or later parities, respectively.Both sire and error components of variance increased with parity. Heritabilities were .18, .09, .10, and .29, for mixed, first, second, and third or later parities. 相似文献
38.
KR Porter PL Summers D Dubois B Puri W Nelson E Henchal JJ Oprandy CG Hayes 《Canadian Metallurgical Quarterly》1993,48(3):440-446
A polymerase chain reaction (PCR) assay was developed to rapidly detect and identify West Nile (WN) virus. The RNA from seven isolates of WN virus from six countries and four other flaviviruses (Kunjin, Japanese encephalitis, St. Louis encephalitis, and yellow fever viruses) was reverse-transcribed (RT) and amplified by PCR. The nucleotide sequences of the amplified products were determined by a rapid, automated DNA sequencing method. The WN virus RT/PCR assay detected the target gene segment of sequencing method. The WN virus RT/PCR assay detected the target gene segment of isolates from both the African-Middle Eastern group and the Indian group with a sensitivity of approximately 0.05 pg of viral RNA. Kunjin virus was the only other flavivirus tested that produced a band of the appropriate size. Five of seven WN virus isolates showed 92-98% homology in the nucleotide sequence of their PCR products. The sequence of one isolate was virtually identical to the published sequence of the Nigerian isolate (99.5% homology). No correlation was established between the degree of nucleotide homology, geographic location, time of isolation, or source of the isolates. 相似文献
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RW Sidwell DF Smee RP Warren JH Huffman BJ Gilbert RA Burger FC Pearson 《Canadian Metallurgical Quarterly》1993,20(4):279-292
ImuVert, a sterile preparation composed primarily of Serratia marcescens membrane vesicles and ribosomes, was significantly inhibitory to murine cytomegalovirus (MCMV) infections in BALB/c mice. Antiviral activity was manifested as increased survivor number and decreased recoverable virus titers in spleens, lungs and salivary glands. Treatments were intraperitoneal (i.p.) beginning 24 h pre, 4 h post- or 24 h post-virus inoculation and then repeated 4 days later. Doses of 5, 16 or 50 micrograms/mouse were effective; 160 micrograms/mouse, which caused host weight loss in toxicity controls, was not inhibitory to the infection. A single i.p. treatment of mice substantially augmented natural killer (NK) cell activity and increased total B-cells, while reducing total T- and T-helper cells. A late (48 h) decline in T-cell function and transient increases in B-cell function were observed in the treated animals. Serum interferon was not induced. Mice pretreated with anti-asialo GM1 antibody to reduce their NK cell populations, then infected with MCMV and treated with ImuVert were protected to the same degree as normal animals. Severe combined immunodeficient mice infected with MCMV and treated with ImuVert were not protected from the infection. These data suggest ImuVert to act by a mechanism other than NK cell activation in preventing MCMV infections. 相似文献