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2.
The role of caffeine or coffee in causing or promoting the incidence of serious disease is equivocal. Two design factors may account for the discrepancies in reported findings on the effects of coffee drinking: (a) imprecision of measurement and (b) confounding variables. A study of 2,714 white U.S. adults disclosed that, of 32 risk factors analyzed by linear and logistic regression, only sex and cigarette smoking were found to be important potential confounders of caffeine and coffee intake. Partial R2 values of the other 30 risk factors were relatively small and were inconsistent for each sex. It is unlikely that any of these factors could explain any of the reported associations between caffeine or coffee consumption and certain diseases. However, certain weak associations with caffeine or coffee intake should be included in the study design when they are known to be risk factors of a disease under investigation. These factors for men are dietary fat intake, vitamin C intake, and body mass index; and for women are vitamin use, alcohol intake, stress, and perceived health status.  相似文献   
3.
The effects of physiological and pathological concentrations of glucocorticoids were investigated using the glucocorticoid antagonist RU486 and the synthetic glucocorticoid dexamethasone, respectively. The effects of these treatments on the concentrations of glutamine and other amino acids in skeletal muscle and plasma and on the rates of release of glutamine and alanine from incubated preparations of skeletal muscle of the rat were investigated. Dexamethasone treatment increased the concentration of glutamine and the rate of release of this amino acid from incubated soleus muscle preparations. This treatment decreased the concentration of glutamine in both gastrocnemius and EDL muscles, but was without effect on the rate of glutamine release from EDL muscles. In contrast, administration of the glucocorticoid antagonist RU486 decreased the rate of glutamine release from muscle. It is concluded that glucocorticoids have marked effects on the metabolism of glutamine by skeletal muscle per se and that these hormones may be important in the control of the rate of glutamine release from muscle in both physiological and pathological conditions.  相似文献   
4.
Carotid sonography is being performed on more than 5,000 participants in the Cardiovascular Health Study, a prospective, multicenter study of cardiovascular disease in men and women aged 65 years and older. The sonographic methods used to examine and measure the extracranial carotid arteries are described. Initial validation studies were performed on 61 subjects with a mean age of 68.6 years. Analysis of within- and between-sonographer differences and between-reader differences were performed for selected variables. In general, the mean absolute differences for within- and between-sonographer comparisons were small, with even less variability between readers. Variability was less for the common carotid artery than for the internal carotid artery. These data suggest that carotid sonography is a reliable and reproducible method for use in the study of carotid atherosclerosis in population studies.  相似文献   
5.
The author reviews recent research findings examining variations in an assertive outreach model. Mental health system and client characteristics that have influenced program implementation are discussed.  相似文献   
6.
Bonfanti  R; Furie  BC; Furie  B; Wagner  DD 《Blood》1989,73(5):1109-1112
PADGEM protein (PADGEM), also known as GMP140, is a platelet alpha- granule membrane protein that is translocated to the external membrane after platelet activation. Although the biosynthesis of this protein was originally thought to be confined to megakaryocytes, the synthesis of PADGEM in endothelial cells was recently demonstrated (McEver et al: Blood 70:1974a, 1987). We now describe the subcellular localization of this protein in endothelial cells. Immunofluorescence staining of permeabilized human umbilical vein endothelial cells with KC4, a well characterized monoclonal antibody to PADGEM, showed positively stained elongated structures similar in distribution and shape to Weibel-Palade bodies. Their identity as Weibel-Palade bodies was confirmed by double label immunofluorescence using KC4 and a polyclonal antiserum to von Willebrand factor (vWf), a protein known to be specifically stored in these organelles. All Weibel-Palade bodies were found to contain PADGEM. In contrast to strong perinuclear staining produced with anti- vWf antibodies, no significant perinuclear staining was obtained with KC4, indicating that relatively little PADGEM is present in the endoplasmic reticulum and in the Golgi apparatus. In endothelial cells treated with secretagogues that stimulate vWf release the elongated structures positive for PADGEM disappeared, further identifying these structures as Weibel-Palade bodies. This observation extends the parallels between Weibel-Palade bodies and alpha-granules and suggests a possible functional association between vWf and PADGEM.  相似文献   
7.
Cancer risk after evaluation for infertility   总被引:3,自引:0,他引:3  
To evaluate cancer risk by various causes of infertility, the authors conducted a retrospective cohort study among 2,335 women evaluated for infertility at the Mayo Clinic between 1935 and 1964. Most cancers occurred at expected frequencies, with the exception of cancers of the thyroid (standardized incidence ratio (SIR) = 2.6) and other endocrine glands (SIR = 6.7), although analyses were based on small numbers. Patients with progesterone deficiencies (31 per cent of the study subjects) had a 20 per cent higher cancer risk than did those with other causes of infertility, with excesses deriving primarily from cancers of the lung, cervix, ovary, and thyroid and from melanoma. Breast cancer risk, however, was not elevated in either patients with progesterone deficiencies (SIR = 0.9) or patients with other causes of infertility (SIR = 1.0). Examination of other parameters of infertility, including age at evaluation, type of infertility (primary vs. secondary), and years of attempted conception, showed no elevated risks of breast cancer in any subgroup. These results fail to support previous studies that have linked progesterone deficiencies among infertile women to elevated breast cancer risk. However, the data suggest a possible involvement of a progesterone deficiency in the etiology of other cancers, particularly thyroid cancer and melanoma.  相似文献   
8.
This column contains the presidential address presented during the Third Annual Meeting of the American Association of Heart Failure Nurses on June 28, 2007, in San Diego, California, titled "Building the Foundation of Excellence in Heart Failure Nursing."  相似文献   
9.
The assessment of the medical lethality and intent of suicide attempts has been considered an important area of research for those interested in suicide. The current study examined the usefulness of the Risk-Rescue Rating Scale with 109 adolescent suicide attempters and found a restricted range of variability, which, in turn, resulted in poor interrater reliability on a number of items. Results suggest that the Risk-Rescue Rating Scale is of limited usefulness with adolescents, and alternative approaches to assessing lethality and suicidal intent with this age group are discussed.  相似文献   
10.
Community pharmacists contribution to the management of drug problems is considerable. As the use of illicit drugs has increased, pharmacists have come under increasing pressure to offer services to problem drug users. However, there is concern among some pharmacists that offering such services may deter other customers. There is particular concern among some pharmacists about needle exchange services. Only 9.5% of Scottish pharmacies offer needle exchange services compared to 69% which are dispensing methadone (57% of which supervise methadone consumption). Qualitative interviews were used in a purposive sample of 10 pharmacies in Scotland. Eight customers were interviewed in each pharmacy to ascertain pharmacy customers’ views on these services. The majority of customers were supportive of these services. Customers were often unaware that the pharmacy they were interviewed in was offering services for people with drug problems. Pharmacy customers were more knowledgeable about, and more supportive, of needle exchange services than they were of methadone. This was because they believed needle exchange services helped to reduce the amount of discarded needles in public places. Pharmacy customers also recognised that needle exchange helped reduce the spread of disease. These findings should be used to encourage more pharmacists to offer needle exchange services.  相似文献   
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