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901.
BACKGROUND: Carcinoma of the pancreas is the fifth leading cancer in the U.S. and has the poorest survival rate of the major malignancies. Recent studies have reported an increased risk of carcinoma of the pancreas in malignant melanoma-prone kindreds and have suggested a link between malignant melanoma and pancreas carcinoma and mutations in the p16INK4 gene. This study evaluates the risk of carcinoma of the pancreas in a population-based cohort of patients with malignant melanoma. METHODS: The malignant melanoma patients were identified from the Surveillance, Epidemiology, and End Results (SEER) program of the National Cancer Institute. The cohort was followed within the SEER system to ascertain the occurrence of subsequent microscopically confirmed primary carcinoma of the pancreas from January 1973 through December 1993. The time of follow-up was expressed as person-years of observation. Standardized incidence ratios (SIR) and 95% confidence intervals (95% CI) were calculated. RESULTS: There were 43,781 malignant melanoma patients providing 263,528 person-years of follow-up. A nearly 2-fold increased risk of subsequent carcinoma of the pancreas in patients diagnosed with malignant melanoma before age 50 years was observed (SIR = 1.76; 95% CI = 0.80-3.34) and the greatest estimated risk occurred in young white females (SIR = 2.27; 95% CI = 0.73-5.30). CONCLUSIONS: These results provide some evidence in support of observations in recent studies that not only a family history of malignant melanoma but also malignant melanoma diagnosed at an early age may be associated with the subsequent development of carcinoma of the pancreas. Further research with larger numbers of melanoma patients is necessary to explore these potential associations. 相似文献
902.
Effect of long-term bovine somatotropin (sometribove) treatment on nitrogen (protein) distribution in Jersey milk 总被引:1,自引:0,他引:1
Twenty-six Jersey cows were assigned randomly to one of two treatments. Twelve cows received biweekly subcutaneous injection of 500 mg of sometribove, USAN (recombinant methionyl bovine somatotropin), beginning 60 +/- 3 d postpartum and continuing throughout one lactation. Fourteen control animals received injections of placebo carrier. Milk samples were taken biweekly on weeks alternate to injection when differences in milk components were expected to be greatest compared with controls. The milk samples were analyzed for total nitrogen, noncasein nitrogen, and non-protein nitrogen. The average SCC for control and treatment groups was 44,000 +/- 47,000 and 56,000 +/- 65,000. Milk from sometribove-treated cows was significantly lower in total protein (3.92, 4.12%), true protein (3.74, 3.95%), and casein (3.11, 3.34%) than that from control cows on d 8 of the 14 d injection cycle. Casein as a percentage of true protein was lower (83.38, 84.52%), and non-protein nitrogen as a percentage of total nitrogen was higher (4.61, 4.26%) in milk from treated cows. The theoretical yield of Cheddar cheese was ca. .07% less for milk from treated cows than from control cows due to ca. 1% less casein as a percentage of true protein in the former. The differences in nitrogen distribution represent the response during the middle of the injection cycle when milk output was the highest and milk protein the lowest rather than the average response for the injection cycle. The results of the study indicate minimal impact on the cheese manufacturer because in practice milk is commingled from many dairies.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
903.
904.
Two flavonoid compounds, viz. 5,7-dimethyl ether of leucopelargonidin 3-0-alpha-L rhamnoside and 5,3'-dimethyl ether of leucocyanidin 3-0-alpha-D galactosyl cellobioside obtained from the bark of F. bengalensis were evaluated for their antioxidant action in hyperlipidemic rats. The results were compared with the activity of a structurally similar flavonoid, quercetin, a known antioxidant. The Ficus compounds showed significant antioxidant effects which may be attributed to their polyphenolic nature. The methylation of two hydrozyl groups in the Ficus flavonoids might have slowed down their antioxidant action as compared to quercetin. 相似文献
905.
P Friedl F Entschladen C Conrad B Niggemann KS Z?nker 《Canadian Metallurgical Quarterly》1998,28(8):2331-2343
Cell migration may depend on integrin-mediated adhesion to and deadhesion from extracellular matrix ligands. This concept, however, has not yet been confirmed for T lymphocytes migrating in three-dimensional extracellular matrices. We investigated receptor involvement in T cell migration combining a three-dimensional collagen matrix model with time-lapse videomicroscopy, computer-assisted cell tracking and confocal microscopy. In collagen lattices, the migration of CD4+ T cells (1) involved interactions with collagen fibers at the leading edge and uropod likewise, (2) occurred independently of the co-clustering of beta1, beta2, or beta3 integrins with F-actin, focal adhesion kinase, and phosphotyrosine at interactions with collagen fibers, (3) was counteracted by high-affinity beta1 integrin binding induced by antibody TS2/16; however, (4) the migration could not be blocked by a combination of adhesion-perturbing anti-beta1, -beta2, -beta3, and alpha v integrin antibodies. Integrin blocking neither affected cell polarization, interaction with fibers, beta1 integrin distribution, migration velocity, path structure, nor the number of locomoting cells in spontaneously migrating or concanavalin A-activated cells. Hence, T lymphocytes migrating in three-dimensional collagen matrices may utilize highly transient interactions with collagen fibers of low adhesivity, thereby differing from focal adhesion-dependent migration strategies employed by other cells. 相似文献
906.
L Cheng NA Rao KS Keefe CP Avila JC Macdonald WR Freeman 《Canadian Metallurgical Quarterly》1998,29(11):930-932
We describe a case of focal cytomegalovirus iritis in a patient with acquired immunodeficiency syndrome (AIDS) who had CMV retinitis. The autopsy showed histologic evidence of focal iritis in the left eye. This iritis was characterized by infiltration of acute inflammatory cells mixed with cytomegalic cells, which was confirmed by CMV-specific immunohistochemical staining. The case suggested that cytomegalovirus could be a direct causative agent of infectious iritis in AIDS patients. 相似文献
907.
Tony Tsang 《Wireless Networks》2003,9(6):575-584
Quality of Service (QoS) measurement of multimedia applications is one of the most important issues for call handoff and call admission control in mobile networks. Based on the QoS measures, we propose a Generalized Stochastic Petri Net (GSPN) based model, called QoS-GSPN, which can express the real-time behavior of QoS measurement for mobile networks. QoS-GSPN performance analysis methodology includes the formal expression and performance analysis environment. It offers the promise of providing real-time behavior predictability for systems characterized by substantial stochastic behavior. With this methodology we model and analyze the call handoff and call admission control schemes in the different multimedia traffic environments of a mobile network. The results of simulation experiments are used to verify the optimal performance achievable for these schemes under the QoS constraints in the given setting of design parameters. 相似文献
908.
B Khoshnood KS Lee S Wall HL Hsieh R Mittendorf 《Canadian Metallurgical Quarterly》1998,148(8):798-805
Unilateral microinjections of acetylcholine into the rat solitary tract nucleus evoked inhibitory effects in electrical activity of symmetrical portions of the diaphragm and external intercostal muscles. Administration of propranolol exerted excitatory respiratory responses. The findings suggest participation of cholin- and noradrenergic systems in inhibitory mechanisms of respiratory control. Different roles of the right and left solitary tract nuclei in their involvement in formation of efferent impulses to bilateral inspiratory muscles, are discussed. 相似文献
909.
Stabilized water droplet dispersed in supercritical carbon dioxide fluid is demonstrated to be an excellent alternative solvent
system to acetic acid for air oxidation of a number of alkyl aromatic hydrocarbons using Co(II) species at mild conditions. 相似文献
910.