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In the United States, renal cell carcinoma (RCC) incidence and the prevalence of obesity, an established risk factor for RCC, have been increasing for several decades. RCC is more common among older individuals. We sought to quantify the contribution of excess adiposity to the rising incidence of RCC among individuals 60 years or older. National Institutes of Health-American Association of Retired Persons Diet and Health Study data (n = 453 859 participants, enrolled in 1995-1996, age at enrollment 50-71 years) were used to estimate multivariable-adjusted hazard ratios (HRs) for RCC across body mass index categories and HRs associated with smoking. Population attributable fractions (PAFs) were calculated using estimated HRs and annual overweight/obesity prevalence from the National Health Interview Survey (1985-2008). PAF estimates were combined with RCC incidence from Surveillance, Epidemiology and End Results-13 to calculate annual percent changes in RCC incidence attributable (and unrelated) to overweight/obesity. We found that between 1995 and 2018, among individuals aged 60 years and older, PAF for overweight/obesity increased from 18% to 29% for all RCCs. In comparison, the PAF for smoking declined from 12% to 9%. RCC incidence increased 1.8% per year (95% confidence interval [CI] 1.5%-2.1%) overall, while RCC incidence attributable to overweight/obesity increased 3.8% per year (95%CI 3.5%-4.2%) and RCC incidence unrelated to overweight/obesity increased 1.2% per year (95% CI 0.9%-1.4%). In conclusion, overweight/obesity appears to have contributed importantly to the rising incidence of RCC in the United States since the mid-1990s. Public health interventions focused on reducing overweight and obesity could help substantially in curbing this trend.  相似文献   
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166Ho-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetramethylene-phosphonate (DOTMP) is a tetraphosphonate molecule radiolabeled with 166Ho that localizes to bone surfaces. This study evaluated pharmacokinetics and radiation-absorbed dose to all organs from this beta-emitting radiopharmaceutical. METHODS: After two 1.1-GBq administrations of 166Ho-DOTMP, data from whole-body counting using a gamma-camera or uptake probe were assessed for reproducibility of whole-body retention in 12 patients with multiple myeloma. The radiation-absorbed dose to normal organs was estimated using MIRD methodology, applying residence times and S values for 166Ho. Marrow dose was estimated from measured activity retained after 18 h. The activity to deliver a therapeutic dose of 25 Gy to the marrow was determined. Methods based on region-of-interest (ROI) and whole-body clearance were evaluated to estimate kidney activity, because the radiotracer is rapidly excreted in the urine. The dose to the surface of the bladder wall was estimated using a dynamic bladder model. RESULTS: In clinical practice, gamma-camera methods were more reliable than uptake probe-based methods for whole-body counting. The intrapatient variability of dose calculations was less than 10% between the 2 tracer studies. Skeletal uptake of 166Ho-DOTMP varied from 19% to 39% (mean, 28%). The activity of 166Ho prescribed for therapy ranged from 38 to 67 GBq (1,030-1,810 mCi). After high-dose therapy, the estimates of absorbed dose to the kidney varied from 1.6 to 4 Gy using the whole-body clearance-based method and from 8.3 to 17.3 Gy using the ROI-based method. Bladder dose ranged from 10 to 20 Gy, bone surface dose ranged from 39 to 57 Gy, and doses to other organs were less than 2 Gy for all patients. Repetitive administration had no impact on tracer biodistribution, pharmacokinetics, or organ dose. CONCLUSION: Pharmacokinetics analysis validated gamma-camera whole-body counting of 166Ho as an appropriate approach to assess clearance and to estimate radiation-absorbed dose to normal organs except the kidneys. Quantitative gamma-camera imaging is difficult and requires scatter subtraction because of the multiple energy emissions of 166Ho. Kidney dose estimates were approximately 5-fold higher when the ROI-based method was used rather than the clearance-based model, and neither appeared reliable. In future clinical trials with 166Ho-DOTMP, we recommend that dose estimation based on the methods described here be used for all organs except the kidneys. Assumptions for the kidney dose require further evaluation.  相似文献   
4.
Animal models have traditionally provided the basis for preliminary investigation of new techniques prior to trials taking place in human subjects. The timing of when to proceed with human trials is difficult, as the accuracy of preclinical models can only be determined with hindsight. This review outlines the progression from transplantation in animal models to man. Now that many transplant procedures are well established, it is possible to assess the predictive value and limitations of animal models. These results are of great importance in the current debate about composite tissue allotransplantation (CTA) and in particular facial transplantation. This progression of CTA from animal models to man is outlined and compared with early renal, cardiac, and liver transplants. There is some evidence to suggest that animal models may have been misleading in CTA and that this has effectively delayed the transition to humans. The role for animal models in facial transplantation, which is currently making the step to clinical trials, is discussed.  相似文献   
5.
An exaggerated fall in blood pressure has been reported with the combination of an alpha 1-blocker and a calcium antagonist. This study investigated, in a placebo-controlled, randomized crossover trial, the clinical usefulness of the combination of prazosin (2 mg b.i.d.) and verapamil (160 mg b.i.d.). Therapeutic efficacy was monitored at regular outpatient visits: average supine and erect blood pressures were, respectively, 175/99 and 176/103 mm Hg with placebo, 160/91 and 164/96 mm Hg with single drug treatment, and 152/84 and 152/89 mm Hg with combination therapy. This significant and clinically useful reduction in blood pressure had an overall magnitude of approximately 28/18 mm Hg (supine) and 29/19 mm Hg (erect). Further measurements were made during a series of intensive study days, and the most important additional finding was a pharmacokinetic interaction that resulted in increased peak concentrations and bioavailability of prazosin. In conclusion, the combination of prazosin and verapamil proved effective in the treatment of 12 patients with essential hypertension who had been poorly responsive to conventional treatment with a beta-blocker and thiazide diuretic.  相似文献   
6.
This study examined longitudinal health and intelligence data to determine whether sensory or motor deficits account for some of the age-related intellectual changes that are commonly seen from midlife onward. Although sensory and motor functioning did not account for the age-related decrements in performance on speeded, visual perceptual tasks found for this sample in previous work, we did find that hearing deficits added error variance to performance estimates on two verbal subtests of the Wechsler scales.  相似文献   
7.
The rejection of sponge matrix allografts across H-2 barriers has generally been found to contain specifically sensitized cytotoxic T cells to donor alloantigen. There is one exception: sponge matrix allografts that differ only with respect to class II alloantigens do not contain specifically sensitized cytotoxic T cells. We therefore investigated the capacity of infiltrating cells removed from sponge matrix allografts to generate delayed hypersensitivity reactions after exposure to fresh alloantigen in a footpad assay. Cells infiltrating class I and II allografts were equally capable of eliciting delayed footpad reactions when injected with specific donor alloantigen into the footpads of naive responder strain mice. Allosensitized T-lymphocyte clones of helper or cytotoxic type were also capable of initiating delayed-type hypersensitivity (DTH) reactions in vivo. We conclude that rejecting allografts across class I or II alloantigenic barriers are infiltrated by cells capable of effecting DTH reactions, in addition to their capacity to exert specific helper or specific cytotoxic reactions. The results also support that both helper and cytotoxic T cells can participate in allospecific DTH reactions.  相似文献   
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An interview study investigating attitudinal and other factors influencing the selection of primary medical care (PMC) agency is described. It focuses on adult patients excluding those with trauma of medical/surgical emergencies and was conducted in part of the Western Region of Melbourne in late 1983, the period immediately prior to the introduction of Medicare. It is based on a cross-sectional survey of in-hours attenders of eight general practices (GP), the Western Region (Community) Health Centre (WRCHC) and the general clinic of the casualty department at the Western General Hospital (WGH). Attenders of these different services differed significantly in their socio-demographic characteristics. WGH attenders were significantly younger and had migrated from non-English speaking countries significantly more often. Male attenders at the WGH had significantly lower socioeconomic status. 71 per cent being not in the workforce. The most commonly stated reasons for attendance at particular services generally were “closeness to home, work”, “recommendation” and “good service”. Reasons given by attenders at the different clinics generally were similar. However GP attenders offered “good service” significantly more often as a reason for choice; WGH attenders offered “cheap/economic reasons” significantly more often and “recommendation” significantly less so. WRCHC attenders offered “workers' compensation” significantly more often. Thirty per cent of attenders overall had attended other than their current clinic during their past three to four illness episodes. While a large majority of patients still attend GP for PMC it is concluded that a pluralist model recognising the legitimacy of different PMC arrangements and multiple use of them by individuals best meets community need. This is likely to be even more true under Medicare. It is concluded that instrumental factors and social networks are important in the selection of PMC, particularly given the limited knowledge of respondents about health services. It is also concluded that cost and economic factors have been given undue weight in selection of primary medical care agency. The use of the WGH casualty department by groups not in the work force, given no real financial advantage in doing so, requires further study.  相似文献   
10.
Eight normotensive subjects received single and multiple doses of cromakalim (1 mg) and placebo in a randomised double-blind cross-over study to examine general tolerance to cromakalim and its effects on blood pressure (BP), heart rate (HR), and pressor responses to norepinephrine (NE) and angiotensin II (AII). In a second study, 10 hypertensive patients whose BP control was unsatisfactory with atenolol 50-100 mg received additional treatment with placebo followed by cromakalim 1 mg daily for 4 weeks. Assessments were made of BP, HR, apparent hepatic blood flow and renal blood flow (RBF), pulmonary function, and the pharmacokinetics of atenolol. Cromakalim was generally well tolerated in both normotensive and hypertensive subjects. In the normotensive group, cromakalim produced a reflex increase in HR without any detectable decrease in BP: average (placebo-subtracted) increases in HR at 4 h were 16 beats/min with subjects in an erect position after the single dose and 14 beats/min after 7 days. Cromakalim had no effect on pressor responses to NE and AII. Addition of cromakalim to atenolol was associated with modest further reductions in BP between 0.5 and 3 h after drug administration, with maximal reductions of 21/14 mm Hg (subjects in supine position) 2 h after the first dose. Cromakalim had no effect on apparent liver blood flow and RBF, pulmonary function, and the steady-state pharmacokinetics of atenolol. Single and multiple 1-mg doses of cromakalim are well tolerated but are associated with only modest vasodilator activity.  相似文献   
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