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A case-control study of squamous cell carcinoma of the upper aerodigestive tract conducted in Heidelberg and Giessen (FRG) provided information on occupational factors in 200 patients and 800 controls (adjusted to sex, age and area of living; 4:1 matched design). The number of subjects exposed to wood dusts, organic chemicals, coal products or to cement was significantly elevated in the tumour group. An increased risk for head and neck cancer was observed after exposition to wood dust (RR = 2,2), organic compounds (RR = 2,4), coal products (RR = 2,7) and especially to cement (RR = 4,4). The cancer risk due to cement exposition showed a positive correlation to the duration of exposition and remained significantly elevated after adjustment for alcohol and tobacco consumption. 相似文献
3.
Leslee J. Shaw Romalisa Miranda-Peats Piotr Slomka John Friedman Sean W. Hayes Daniel S. Berman Gary V. Heller Marcin Dada William E. Boden Paul Casperson Robert A. O’Rourke Ronald Schwartz William S. Weintraub David J. Maron Spencer King Koon Teo Pamela Hartigan 《Journal of nuclear cardiology》2006,13(5):685-698
Background Stress gated myocardial perfusion single photon emission computed tomography (gSPECT) is increasingly used before and after
intercurrent therapeutic intervention and is the basis for ongoing evaluation in the Department of Veterans Affairs clinical
outcomes utilizing revascularization and aggressive drug evaluation (COURAGE) trial.
Methods and Results The COURAGE trial is a North American multicenter randomized clinical trial that enrolled 2287 patients to aggressive medical
therapy vs percutaneous coronary intervention plus aggressive medical therapy. Three COURAGE nuclear substudies have been
designed. The goals of substudy 0 are to examine the diagnostic accuracy of the extent and severity of inducible ischemia
at baseline in COURAGE patients compared with patient symptoms and quantitative coronary angiography and to explore the relationship
between inducible ischemia and the benefit from revascularization when added to medical therapy. Substudy 1 will correlate
the extent and severity of provocative ischemia with the frequency, quality, and instability of recurrent symptoms in postcatheterization
patients. Substudy 2 (n _ 300) will examine the usefulness of sequential gSPECT monitoring 6 to 18 months after therapeutic
intervention. Together, these nuclear substudies will evaluate the role of gSPECT to determine the effectiveness of aggressive
risk-factor modifications, lifestyle interventions, and anti-ischemic medical therapies with or without revascularization
in reducing patients’ ischemic burdens.
Conclusions The unfolding of evidence on the application of gSPECT in trials such as COURAGE defines a new era for nuclear cardiology.
We hope the evidence that emerges from the COURAGE trial will further establish the role of nuclear imaging in the evidence-based
management of patients with stable coronary disease.
The COURAGE trial was supported by the Cooperative Studies Program of the Department of Veterans Affairs Office of Research
and Development in collaboration with the Canadian Institutes of Health Research. Unrestricted research grants were obtained
from Merck & Co; Pfizer Pharmaceuticals; Bristol-Myers Squibb Medical Imaging; Astellas Pharma; Kos Pharmaceuticals; Data
Scope; Astra Zeneca Pharmaceuticals; Astra-Zeneca-Canada; Schering-Plough Coorporation, Ltd; Sanofi-Aventis, Inc; First Horizon;
and GE Healthcare. All industrial funding for this trial was directed through the Department of Veterans Affairs. Additional
funding for this substudy was provided by grants to the Department of Veterans Affairs and Canadian Institutes of Health Research
from Astellas Pharma and Bristol-Myers-Squibb Medical Imaging. 相似文献
4.
In newly diagnosed adult patients with epilepsy followed prospectively on monotherapy, carbamazepine and phenytoin were associated with a fall in plasma uric acid, but sodium valproate and phenobarbitone were associated with a rise in plasma uric acid. The mechanisms and significance of these findings are discussed. 相似文献
5.
The distribution of the pituitary antidiuretic hormone throughout the vertebrate series 总被引:1,自引:0,他引:1
Heller H 《The Journal of physiology》1941,99(2):246-256
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Dramatic progress in the understanding and treatment of erectile impotence has occurred over the past decade. Most cases have an organic cause that is related to vascular (arterial or venous) supply, innervation, or the hormonal milieu of the penis. Multifactorial causes of organic impotence are common and include diabetes mellitus, alcoholism, renal failure, and liver failure. Medications may cause impotence by a variety of mechanisms. The history and physical examination, along with simple laboratory tests, are the mainstay of evaluation and may be performed appropriately by family physicians. Successful new forms of nonsurgical treatment include penile self-injection with papaverine (sometimes with phentolamine) and penile-suction devices. Penile prostheses have been improved greatly in recent years. The patient may select among semirigid, multicomponent inflatable, and self-contained inflatable devices. New surgical treatments include penile arterial revascularization (for atherosclerosis) and ligation of the dorsal vein of the penis (for venous leak). 相似文献
9.
Twin study of genetic and environmental effects on lipid levels 总被引:4,自引:0,他引:4
D L O'Connell R F Heller D C Roberts J R Allen J C Knapp P L Steele D Silove 《Genetic epidemiology》1988,5(5):323-341
A study of 106 pairs of monozygotic (MZ) and 94 pairs of dizygotic (DZ) twins tested the hypothesis that part of the previously described genetic influence on blood lipid levels can be ascribed to closer similarities among MZ than among DZ twin pairs in environmental factors that affect lipid levels. Participants were adult twin volunteers (age 17-66; 64 male and 136 female pairs) who were selected from the NH & MRC Twin Registry or were respondents to advertisements. They completed a 4-day weighed food diary from which mean nutrient intake was derived. Information on lifestyle and demographic variables was obtained by questionnaire and a nonfasting blood sample was taken for measures of total, low-density lipoprotein (LDL) cholesterol, and high-density lipoprotein (HDL) cholesterol and the HDL2 and HDL3 subfractions. Height and weight were measured, and body mass index (BMI) was calculated (kg/m2). Estimates of the heritability of sex-adjusted lipid levels were 0.72 for total cholesterol, 0.79 for HDL cholesterol, 0.69 for HDL2, 0.20 for HDL3, 1.06 for LDL cholesterol, and 0.44 for sex-adjusted BMI. In all cases except for HDL3, genetic variance was statistically significant. After adjusting for the effects of environmental variables in three different ways, the estimates of heritability were somewhat lower for total cholesterol, HDL2, and BMI, and those for HDL cholesterol (borderline) and LDL cholesterol (definitely) remained statistically significant but were decreased. A genetic influence on HDL3 was not found. Adjusted heritability estimates obtained from one method of analysis were 0.35 for total cholesterol, 0.49 for HDL, 0.04 for HDL2, -0.34 for HDL3, 0.66 for LDL, and 0.32 for BMI. These results suggest that the assumptions made in the classical twin study approach are not appropriate when examining genetic effects on lipid levels or BMI, or indeed on any biological variable that may be affected by environmental factors that tend to be more similar in MZ twins than in DZ twins. In these circumstances, more complex models may be needed to differentiate between genetic and environmental influences. 相似文献
10.