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71.
Doody MM Freedman DM Alexander BH Hauptmann M Miller JS Rao RS Mabuchi K Ron E Sigurdson AJ Linet MS 《Cancer》2006,106(12):2707-2715
BACKGROUND: Studies of atomic bomb survivors and medically exposed populations have demonstrated an increased risk of breast cancer associated with acute or protracted, intermediate-dose or high-dose, ionizing radiation; however, the risks associated with low-dose and low-dose-rate (protracted) exposures are less certain. METHODS: The authors evaluated incident breast cancer risks from 1983 to 1998 according to employment characteristics and a 4-level proxy index for cumulative radiation exposure based on 2 mail surveys among 56,436 U.S. female radiologic technologists who were certified from 1925 to 1980, adjusting for established breast cancer risk factors. RESULTS: During follow-up, 1050 new breast cancer diagnoses were ascertained. Compared with radiologic technologists who began working in 1970 or later, adjusted breast cancer risks for those who first worked in the 1960s, 1950s, 1940s, from 1935 to 1939, and before 1935 were 1.0 (95% confidence interval [CI], 0.8-1.2), 1.2 (95% CI, 0.9-1.6), 1.0 (95% CI, 0.7-1.5), 1.8 (95% CI, 1.0-3.2), and 2.9 (95% CI, 1.3-6.2), respectively. The risk rose with the number of years worked before 1940 (P value for trend = .002) and was elevated significantly among those who began working before age 17 years (relative risk, 2.6; 95% CI, 1.3-5.1; 10 women) but was not related to the total years worked in the 1940s or later. Compared with technologists who had a Level 1 (minimal) proxy index for cumulative radiation exposure, breast cancer risks were 1.0 (95% CI, 0.9-1.2), 1.0 (95% CI, 0.7-1.3), and 1.5 (95% CI, 1.0-2.2), respectively, for technologists who had Level 2, Level 3, and Level 4 (highest) exposure. CONCLUSIONS: Breast cancer risk was elevated significantly in female radiologic technologists who experienced daily low-dose radiation exposures over several years that potentially resulted in appreciable cumulative exposure. The increased risk for total years worked before 1940, but not later, was consistent with decreasing occupational radiation exposures, improvements in radiation technology, and more stringent radiation protection standards over time. 相似文献
72.
B S Levy E Sigurdson J Mandel E Laudon J Pearson 《American journal of epidemiology》1976,103(4):362-368
The recent discovery of over one million asbestos-like fibers per liter of Duluth tap water and the suggestive evidence of a link between certain gastrointestinal (GI) cancers and work exposure to asbestos fibers in the air prompted this study. GI cancer incidence data were gathered for Duluth in the same manner as data previously gathered for comparison cities, Minneapolis and St. Paul. Although some differences in GI cancer incidence occurred among the three cities in 1969-1971, there was no consistent pattern of statistically significant differences observed. The number of GI cancers diagnosed in Duluth residents in 1972 was similar to that in each of the previous three years. This study represents the start of ongoing cancer surveillance in Duluth. 相似文献
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The aim of this work was to study the influence of bacterial cell concentrations and inorganic anions on lysis of Streptococcus mutans BHT by human salivary lysozyme (HSL). HSL was partly purified from saliva by ion exchange chromatography. The bacteria were grown in a synthetic medium containing 3H-thymidine to monitor DNA release. The experiments demonstrated that release 3H-thymidine was dependent on the bacterial cell concentration and an apparent Km-value corresponding to approximately 2.9 × 108 cells/ml was calculated. The influence of I?, Br?, Cl?, F?, HCO3? and SCN? on bacteriolysis was studied. All anions tested were slightly inhibitory on the action of HSL. The inhibition varied from 7 to 76% depending on the ion and ionic strength. The order of addition of HSL and sodium chloride caused different lytic responses. This was reflected by the amount of HSL adsorbed by the bacteria. 相似文献
76.
Regional chemotherapy for colorectal hepatic metastases: Evidence for improved survival with new drug combinations 总被引:1,自引:0,他引:1
E. Sutanto-Ward BS Y. Arisawa MD PhD S. Tremiterra MD Dr. E. R. Sigurdson MD PhD 《Annals of surgical oncology》1996,3(1):36-43
Background: In patients with colorectal hepatic metastases, response rates with hepatic arterial infusion (HAI) FUdR (5-Fluoro-2-deoxyuridine)
are significantly higher than with systemic fluoropyrimidines. We report a novel animal model of intrahepatic therapy for
hepatic metastasis for the study of methods to increase response rates and improve survival.
Methods: BD-IX rats are injected intrasplenically with K12/TRb cells. When hepatic metastases are established, animals are treated
with hepatic or systemic chemotherapy, and the response to treatment, survival, and cause of death is determined.
Results: Significant responses were observed with low- and high-dose HAI FUdR (p=0.03 and 0.001, respectively). Only high-dose FUdR
controlled hepatic disease. HAI FUdR alone did not prolong survival compared with control, but combination systemic FUdR and
HAI FUdR did (p=0.04). Continuous HAI of either 5-fluorouridine or mitomycin C has not previously been reported. There was
no significant difference in response to FUdR, 5-fluorouridine, or mitomycin C. However, combination HA bolus mitomycin C
plus either HAI 5-fluorouridine or HAI mitomycin C showed synergy with improved survival compared with all other treatment
groups (p<0.0001).
Conclusions: The combination of bolus hepatic artery mitomycin C with either HAI mitomycin C or HAI 5-fluorouridine yields significant
response rates, and survival is improved by this novel combination therapy. 相似文献
77.
MP Busch ; EA Operskalski ; JW Mosley ; CE Stevens ; ER Schiff ; SH Kleinman ; H Lee ; M Lee ; M Harris 《Transfusion》1994,34(10):858-864
BACKGROUND: The long-term course of human immunodeficiency virus type 1 (HIV-1)-related disease among seropositive blood donors has not been described. The enrollment and epidemiologic background of HIV-1- infected donors in the Transfusion Safety Study and their immunologic and clinical progression are described. STUDY DESIGN AND METHODS: Through the testing of approximately 200,000 sera from donations made in late 1984 and early 1985, 146 anti-HIV-1-positive donors and 151 uninfected matched donors were enrolled. These two cohorts were followed with 6-month interval histories and laboratory testing. RESULTS: Seropositive donors detected before the institution of routine anti-HIV-1 screening disproportionately were first-time donors and men with exclusively male sexual contacts. The actuarial probability of a person's developing AIDS within 7 years after donation was 40 percent; the probability of a person's dying of AIDS was 28 percent. AIDS developed more often when the donor was p24 antigen-positive at donation. Over a 3-year period, significant decreases occurred in CD4+, CD2+CD26+, CD4+CD29+, and CD20+CD21+ counts, but not in CD8+ subsets, CD20+, or CD14+. CONCLUSION: The high proportions of first-time donations and exclusively homosexual men among seropositive donors suggest that test-seeking may have contributed to the high HIV-1 prevalence in the repository. Implementation of alternative test sites when routine donor screening began in 1985 may have averted many high- risk donations. The disease course in HIV-1-infected donors had the same wide spectrum of immunologic and clinical manifestations as were reported for other cohorts. 相似文献
78.
Henry LR Sigurdson E Ross EA Lee JS Watson JC Cheng JD Freedman GM Konski A Hoffman JP 《Annals of surgical oncology》2007,14(7):2000-2009
Background Recurrence in the pelvis after resection of a rectal or rectosigmoid cancer presents a dilemma. Resection offers the only
reasonable probability for cure, but at the cost of perioperative morbidity and potential mortality. Clinical decision making
remains difficult.
Methods Patients resected with curative intent for isolated pelvic recurrences after curative colorectal surgery from 1988 through
2003 were reviewed retrospectively. Clinical and pathologic factors, salvage operations, and complications were recorded.
The primary measured outcome was overall survival. Univariate and multivariate analyses were conducted to identify prognostic
factors of improved outcome.
Results Ninety patients underwent an attempt at curative resection of a pelvic recurrence with median follow-up of 31 months. Complications
occurred in 53% of patients. Operative mortality was 4.4% (4 of 90). Median overall survival was 38 months, and estimated
5-year survival was 40%. A total of 51 of 86 patients had known recurrences (15 local, 16 distant, 20 both). Multivariate
analysis revealed that preoperative carcinoembryonic antigen level and final margin status were statistically significant
predictors of outcome.
Conclusions The resection of pelvic recurrences after colorectal surgery for cancer can be performed with low mortality and good long-term
outcome; however, morbidity from such procedures is high. Low preoperative carcinoembryonic antigen and negative margin of
resection predict improved survival.
Presented at the Society of Surgical Oncology, 58th Annual Cancer Symposium, Atlanta, GA, March 3–6, 2005. 相似文献
79.
Malik S, Kakar N, Hasnain S, Ahmad J, Wilcox ER, Naz S. Epidemiology of Van der Woude syndrome from mutational analyses in affected patients from Pakistan. Mutations in IRF6 cause Van der Woude syndrome (VWS), one of the most common syndromes associated with cleft lip (CL) with or without cleft palate (CP). The presence of pits on the lower lip of patients is the most characteristic feature of the syndrome. We have identified three novel and seven previously reported IRF6 mutations in 12 of 16 unrelated families segregating VWS from Pakistan. The three newly identified mutations include a frameshift (c.568delG) and two missense mutations c.295G>A (p.G99S) and c.1219T>C (p.S407P). Recent functional studies on IRF6 and the three‐dimensional structure of IRF5 carboxy (C) terminus, a protein encoded by a paralog of IRF6, shed light on the p.S407P substitution. Additionally, the identification of the same mutations responsible for VWS in Pakistan, as reported in other global populations worldwide, marks these residues as mutational hotspots and indicates their essential role in structural stability or function of IRF6. This is the first study of VWS in Pakistan and we estimate that 1 in 100 patients with CL with or without CP (CL/P) are affected in the Pakistani population predominantly from the Punjab area. 相似文献
80.