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101.
This study shows that in The Netherlands there is a changing pattern in incidence of renal replacement therapy over time when adjusted for age and sex. There has been an almost linear increase in crude incidence rates during four decades. However, unlike the situation elsewhere in the Western world, a flattening of the curve has been observed during the last six years. The growing incidence of end-stage renal disease (ESRD) due to especially hypertensive renovascular disease and diabetes mellitus type 2 has been neutralized by a decrease in ESRD due to glomerulonephritis, urologic interstitial nephritis, and diabetes mellitus type 1. The latter observations suggest that renoprotective interventions can be successful on a population level, and thus, provide hope for the future. To battle the increase in ESRD due to atherosclerosis and diabetes mellitus type 2-related renal disease, it is important that screening programs are being developed that enable us to identify in an early phase patients at risk for development of ESRD who may benefit from preventive strategies. Population screening for albuminuria will be helpful in this respect.  相似文献   
102.
The adverse consequences of passive smoking have spurred efforts to reduce environmental tobacco smoke (ETS) exposure among children, particularly in the home. For children with asthma, teaching them to avoid tobacco smoke at home is an important element of patient self-management. This strategy assumes that children can accurately assess household smoking behaviors and the level of their own exposure in the home. This study compared child and parental assessments of household smoking behaviors in an urban, low-income and largely ethnic minority sample of asthmatic children and their parents. While there was general parent-child agreement on the smoking status of household members, there was less agreement on duration of household smoking and the child's exposure to ETS. Objective validation measures (cotinine, nicotine) suggest that parents were better able than their children to assess hours of indoor smoking. Children's assessment of the extent of exposure to ETS may be problematic, with important implications for asthma patient self-management efforts.  相似文献   
103.
PURPOSE: To evaluate the impact of different tabletops with or without a knee support on the position of the rectum, prostate, and bulb of the penis; and to evaluate the effect of these patient-positioning devices on treatment planning. METHODS AND MATERIALS: For 10 male volunteers, five MRI scans were made in four different positions: on a flat tabletop with knee support, on a flat tabletop without knee support, on a rounded tabletop with knee support, and on a rounded tabletop without knee support. The fifth scan was in the same position as the first. With image registration, the position differences of the rectum, prostate, and bulb of the penis were measured at several points in a sagittal plane through the central axis of the prostate. A planning target volume was generated from the delineated prostates with a margin of 10 mm in three dimensions. A three-field treatment plan with a prescribed dose of 78 Gy to the International Commission on Radiation Units and Measurements point was automatically generated from each planning target volume. Dose-volume histograms were calculated for all rectal walls. RESULTS: The shape of the tabletop did not affect the rectum and prostate position. Addition of a knee support shifted the anterior and posterior rectal walls dorsally. For the anterior rectal wall, the maximum dorsal shift was 9.9 mm (standard error of the mean [SEM] 1.7 mm) at the top of the prostate. For the posterior rectal wall, the maximum dorsal shift was 10.2 mm (SEM 1.5 mm) at the middle of the prostate. Therefore, the rectal filling was pushed caudally when a knee support was added. The knee support caused a rotation of the prostate around the left-right axis at the apex (i.e., a dorsal rotation) by 5.6 degrees (SEM 0.8 degrees ) and shifts in the caudal and dorsal directions of 2.6 mm (SEM 0.4 cm) and 1.4 mm (SEM 0.6 mm), respectively. The position of the bulb of the penis was not influenced by the use of a knee support or rounded tabletop. The volume of the rectal wall receiving the same dose range (e.g., 40-75 Gy) was reduced by 3.5% (SEM 0.9%) when a knee support was added. No significant differences were observed between the first and fifth scan (flat tabletop with knee support) for all measured points, thereby excluding time trends. CONCLUSIONS: The rectum and prostate were significantly shifted dorsally by the use of a knee support. The rectum shifted more than the prostate, resulting in a dose benefit compared with irradiation without knee support. The shape of the tabletop did not influence the rectum or prostate position.  相似文献   
104.
PURPOSE: To identify the anatomic structures whose damage or malfunction cause late dysphagia and aspiration after intensive chemotherapy and radiotherapy (RT) for head-and-neck cancer, and to explore whether they can be spared by intensity-modulated RT (IMRT) without compromising target RT. METHODS AND MATERIALS: A total of 26 patients receiving RT concurrent with gemcitabine, a regimen associated with a high rate of late dysphagia and aspiration, underwent prospective evaluation of swallowing with videofluoroscopy (VF), direct endoscopy, and CT. To assess whether the VF abnormalities were regimen specific, they were compared with the VF findings of 6 patients presenting with dysphagia after RT concurrent with high-dose intra-arterial cisplatin. The anatomic structures whose malfunction was likely to cause each of the VF abnormalities common to both regimens were determined by literature review. Pre- and posttherapy CT scans were reviewed for evidence of posttherapy damage to each of these structures, and those demonstrating posttherapy changes were deemed dysphagia/aspiration-related structures (DARS). Standard three-dimensional (3D) RT, standard IMRT (stIMRT), and dysphagia-optimized IMRT (doIMRT) plans in which sparing of the DARS was included in the optimization cost function, were produced for each of 20 consecutive patients with advanced head-and-neck cancer. RESULTS: The posttherapy VF abnormalities common to both regimens included weakness of the posterior motion of the base of tongue, prolonged pharyngeal transit time, lack of coordination between the swallowing phases, reduced elevation of the larynx, and reduced laryngeal closure and epiglottic inversion, contributing to a high rate of aspiration. The anatomic structures whose malfunction was the likely cause of each of these abnormalities, and that also demonstrated anatomic changes after RT concurrent with gemcitabine doses associated with dysphagia and aspiration, were the pharyngeal constrictor muscles (median thickness near midline 2.5 mm before therapy vs. 7 mm after therapy; p = 0.001), the supraglottic larynx (median thickness, 2 mm before therapy vs. 4 mm after therapy; p < 0.001), and, similarly, the glottic larynx. The constrictors and the glottic and supraglottic larynx were, therefore, deemed the DARS. The lowest maximal dose delivered to a stricture volume was 50 Gy. Reducing the volumes of the DARS receiving > or =50 Gy (V(50)) was, therefore, a planning and evaluation goal. Compared with the 3D plans, stIMRT reduced the V(50) of the pharyngeal constrictors by 10% on average (range, 0-36%, p < 0.001), and doIMRT reduced these volumes further, by an additional 10% on average (range, 0-38%; p <0.001). The V(50) of the larynx (glottic + supraglottic) was reduced marginally by stIMRT compared with 3D (by 7% on average, range, 0-56%; p = 0.054), and doIMRT reduced these volumes by an additional 11%, on average (range, 0-41%; p = 0.002). doIMRT reduced laryngeal V(50) compared with 3D, by 18% on average (range 0-61%; p = 0.001). Certain target delineation rules facilitated sparing of the DARS by IMRT. The maximal DARS doses were not reduced by IMRT because of their partial overlap with the targets. stIMRT and doIMRT did not differ in target doses, parotid gland mean dose, spinal cord, or nonspecified tissue maximal dose. CONCLUSIONS: The structures whose damage may cause dysphagia and aspiration after intensive chemotherapy and RT are the pharyngeal constrictors and the glottic and supraglottic larynx. Compared with 3D-RT, moderate sparing of these structures was achieved by stIMRT, and an additional benefit, whose extent varied among the patients, was gained by doIMRT, without compromising target doses. Clinical validation is required to determine whether the dosimetric gains are translated into clinical ones.  相似文献   
105.
OBJECTIVE: To explore effects on serum lipids, pituitary-gonadal axis, prostate and bone turnover of the administration of the mixed oestrogen agonist/antagonist raloxifene in healthy elderly men. PARTICIPANTS: Thirty healthy men aged 60-70 years randomly received raloxifene 120 mg/day (n=15) or placebo (n=15) for 3 months. MEASUREMENTS: In this double-blind, placebo-controlled study, serum gonadotrophins, sex hormones, prostate specific antigen (PSA), a marker of bone turnover, urinary hydroxyproline (OHPro) and cholesterol were measured at baseline and after 3 months. RESULTS: Raloxifene significantly increased serum concentrations of LH and FSH (by 29% and 21%), total testosterone (20%), free testosterone (16%) and bioavailable testosterone (not bound to sex hormone-binding globulin (SHBG; 20%). In parallel with testosterone, 17 beta-oestradiol also increased by 21%. SHBG increased by 7%. Total cholesterol (TChol) decreased significantly, from 5.7 to 5.5 mmol/l (P=0.03). Low-density lipoprotein cholesterol (LDL-c) and high-density lipoprotein cholesterol (HDL-c) showed a trend to decrease. Overall, there was no change in urinary OHPro/creatinine ratio as a marker for bone resorption. However, the raloxifene-induced increases in both serum testosterone and 17 beta-oestradiol were significantly related to a lower OHPro/creatinine ratio. Total PSA increased by 17% without significant changes in free PSA or free/total PSA ratio. Participants reported no side effects and raloxifene was well tolerated. CONCLUSION: In healthy elderly man, raloxifene 120 mg/day for 3 months increased LH, FSH and sex steroid hormones. Potentially beneficial effects were the small but significant decrease in TChol and the trend towards a decrease in LDL-c. Negative effects were the trend towards a decrease in HDL-c and the significant increase in serum PSA. A decrease in markers of bone resorption during raloxifene treatment was found only in men with relatively high increases in serum testosterone and 17 beta-oestradiol. Overall, there were no clear beneficial effects of administration of raloxifene to ageing men in this preliminary investigation.  相似文献   
106.
107.
Phytoestrogens such as isoflavonoids and lignans have been postulated as breast cancer protective constituents in soy and whole-grain cereals. We investigated the ability of isoflavones (IFs) and flaxseed to modulate spontaneous mammary tumor development in female heterozygous Tg.NK (MMTV/c-neu) mice. Two different exposure protocols were applied, either from 4 wk of age onward (postweaning) or during gestation and lactation (perinatal). In the postweaning exposure study, mice were fed IFs or flaxseed in a high-fat diet. In addition, flaxseed in a low-fat diet was tested. Postweaning exposure to IFs and flaxseed tended to accelerate the onset of mammary adenocarcinoma development, although tumor burden at necropsy was not changed significantly. Perinatal IF exposure resulted in enhanced mammary gland differentiation, but palpable mammary tumor onset was not affected. However, tumor burden at necropsy in the perinatal exposure study was significantly increased in the medium- and high-IF dose groups. Comparison of both exposure scenarios revealed a strongly accelerated onset of tumor growth after perinatal high-fat diet exposure compared with the low-fat diet. This study shows that breast cancer-modulating effects of phytoestrogens are dependent both on the background diet and on the timing of exposure in the life cycle.  相似文献   
108.
OBJECTIVE: To quantify the relative contribution of elevated 2-hr glucose, fasting glucose (FPG), and HbA1c to all-cause mortality. STUDY DESIGN AND SETTING: A joint analysis of two prospective studies with baseline glycemia measurements. RESULTS: The multivariate adjusted hazard ratios (HRs) corresponding to a one standard deviation increase in HbA1c were 1.14 (95% CI 1.03-1.25), 1.08 (0.98-1.19) for FPG and 1.15 (1.05-1.27) for 2-hr glucose, respectively. Entering the 2-hr glucose to the model based on the FPG and HbA1c significantly improved the prediction of mortality, whereas neither FPG, nor HbA1c added significant information once 2-hr glucose was in the models. In subjects with FPG <7.0 mmol/L and HbA1c < or = 6.5%, the HR was 1.35 (1.03-1.78) in men with 2-hr glucose > or = 7.8 mmol/L compared with men with 2-hr glucose <7.8 mmol/L. CONCLUSION: Elevated 2-hr glucose was a predictor of mortality independent of the levels of fasting glucose and HbA1c.  相似文献   
109.
Objective: To evaluate the effect of the selective estrogen receptor modulator raloxifene hydrochloride (Evista, Eli Lilly and Company, Indianapolis, IN) on plasma levels of β-endorphin, and to determine whether β-endorphin levels and menopausal symptoms are related.

Design: A randomized, double-blind, placebo-controlled pilot study.

Setting: Endocrinology outpatient department.

Patient(s): Forty postmenopausal women.

Intervention(s): The women received raloxifene, 60 mg/d, or placebo for 3 months. A questionnaire on climacteric symptoms was administered before and after treatment.

Main Outcome Measure(s): Circulating levels of β-endorphin, climacteric symptom score, and correlation with β-endorphin levels.

Result(s): Raloxifene treatment significantly increased levels of β-endorphin and did not significantly affect climacteric symptoms, with the exception of worsening vasomotor symptoms. No significant relation was seen between plasma levels of β-endorphin and climacteric symptoms.

Conclusion(s): Raloxifene modulates plasma levels of β-endorphin without concomitantly relieving climacteric symptoms, as seen with hormone replacement therapy.  相似文献   

110.
OBJECTIVE: In 196 type 1 diabetic subjects and 195 nondiabetic subjects aged 30-55 years, we examined whether C-reactive protein (CRP) is elevated in diabetes and whether CRP is associated with coronary artery calcification (CAC). RESEARCH DESIGN AND METHODS: CRP was measured with a highly sensitive immunoassay. CAC was measured using electron beam computed tomography. RESULTS: CRP was elevated in diabetic women compared with nondiabetic women (median 1.62 vs. 0.85 mg/l, P < 0.001) independently of other factors, but was similar in diabetic and nondiabetic men (median 0.82 vs. 0.81 mg/l). Insulin dose per day was positively correlated with CRP in diabetic women (Spearman's rho = 0.36, P = 0.0003) but much less so in men (rho = 0.16, P = 0.09). Being in the top tertile for CRP was associated with CAC in diabetic and nondiabetic men even after adjustment for other risk factors (adjusted odds ratio [OR] = 4.6 and 4.3, respectively, P = 0.02 for both). In nondiabetic women, being in the top tertile for CRP was associated with CAC (OR 3.1, P = 0.04), but not independently of BMI (OR = 1 after adjustment). Among diabetic women the association was not significant even before adjustment for BMI (OR = 2.6, P = 0.07). CONCLUSIONS: Elevated CRP in diabetic women might reflect a particular sensitivity to insulin levels or might reflect insulin resistance. In general, CRP is an important marker of subclinical atherosclerosis, but the clinical significance of elevated CRP in diabetic women needs to be addressed in prospective studies, since CRP was not clearly associated with CAC in this group.  相似文献   
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