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排序方式: 共有1526条查询结果,搜索用时 15 毫秒
71.
Jon B. Christianson Karen M. Volmar Jeffrey Alexander Dennis P. Scanlon 《Journal of general internal medicine》2010,25(11):1235-1241
BACKGROUND
Public reporting of provider performance can assist consumers in their choice of providers and stimulate providers to improve quality. Reporting of quality measures is supported by advocates of health care reform across the political spectrum. 相似文献72.
MacIntosh DL Kabiru C Scanlon KA Ryan PB 《Journal of exposure analysis and environmental epidemiology》2000,10(2):196-205
Semi-quantitative food checklists and duplicate beverage samples were collected from up to 80 individuals in Maryland in 1995-1996 in as many as six approximately equally spaced sampling cycles as part of a pilot longitudinal exposure investigation. The duplicate beverage samples were homogenized and analyzed for arsenic (As), cadmium (Cd), chromium (Cr) and lead (Pb) using inductively coupled plasma mass spectrometry (ICP-MS). Metal concentrations (microg/kg) and weights of the duplicate beverage samples (kg/day) were used to derive average daily exposure (microg/day) for each metal. Mixed models and generalized linear models were used to evaluate temporal and population variability of the beverage consumption rates, the log-transformed metal concentrations in the beverage samples, and the associated exposures. The mean number of beverage servings consumed per day was 3.4 (SD 1.9). The temporal variability of the total beverage consumption rates was found to be significant (p = 0.0476). As, Cd, Cr, and Pb were present at quantifiable levels in 93.5, 76.0, 93.5, and 96.7% of the beverage samples, respectively. The mean concentration in the samples was 2.0 (SD 4.4) microg/kg for As, 0.9 (1.6) for Cd, 29.2 (138.5) for Cr, and 2.0 (2.4) for Pb. The mean log-transformed concentrations for As, Cr and Pb and exposure for As varied by as much as a factor of 3 across sampling cycles and were statistically significantly different (p<0.05). Concentrations and exposures of all four metals varied significantly among participants. These findings are discussed with respect to the data collection methods, results from comparable studies, and implications for exposure and risk assessment. 相似文献
73.
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75.
Nesby-O'Dell S Scanlon KS Cogswell ME Gillespie C Hollis BW Looker AC Allen C Doughertly C Gunter EW Bowman BA 《The American journal of clinical nutrition》2002,76(1):187-192
BACKGROUND: Recent reports of rickets among African American children drew attention to the vitamin D status of these infants and their mothers. African American women are at higher risk of vitamin D deficiency than are white women, but few studies have examined determinants of hypovitaminosis D in this population. OBJECTIVE: We examined the prevalence and determinants of hypovitaminosis D among African American and white women of reproductive age. DESIGN: We examined 1546 African American women and 1426 white women aged 15-49 y who were not pregnant and who participated in the third National Health and Nutrition Examination Survey (1988-1994). Hypovitaminosis D was defined as a serum 25-hydroxyvitamin D concentration < or =37.5 nmol/L. Multiple logistic regression was used to examine the independent association of dietary, demographic, and behavioral determinants of hypovitaminosis D. RESULTS: The prevalence of hypovitaminosis D was 42.4 +/- 3.1% ( +/- SE) among African Americans and 4.2 +/- 0.7% among whites. Among African Americans, hypovitaminosis D was independently associated with consumption of milk or breakfast cereal <3 times/wk, no use of vitamin D supplements, season, urban residence, low body mass index, and no use of oral contraceptives. Even among 243 African Americans who consumed the adequate intake of vitamin D from supplements (200 IU/d), 28.2 +/- 2.7% had hypovitaminosis D. CONCLUSIONS: The high prevalence of hypovitaminosis D among African American women warrants further examination of vitamin D recommendations for these women. The determinants of hypovitaminosis D among women should be considered when these women are advised on dietary intake and supplement use. 相似文献
76.
Three new prodrugs for suicide gene therapy using carboxypeptidase G2 elicit bystander efficacy in two xenograft models 总被引:4,自引:0,他引:4
Friedlos F Davies L Scanlon I Ogilvie LM Martin J Stribbling SM Spooner RA Niculescu-Duvaz I Marais R Springer CJ 《Cancer research》2002,62(6):1724-1729
Three new prodrugs, [prodrug 1: 4-[bis(2-iodoethyl)amino]-phenyloxycarbonyl-L-glutamic acid; prodrug 2: 3-fluoro-4-[bis(2-chlorethyl)amino]benzoyl-L-glutamic acid; and prodrug 3: 3,5-difluoro-4-[bis(2-iodoethyl)amino]benzoyl-L-glutamic acid] have been assessed for use with a mutant of carboxypeptidase G2 (CPG2, glutamate carboxypeptidase, EC 3.4.17.11,) engineered to be tethered to the outer tumor cell surface (stCPG2(Q)3) as the activating enzyme in suicide gene therapy systems. All three of the prodrugs produce much greater cytotoxicity differentials between stCPG2(Q)3- and control beta-galactosidase (beta-gal)-expressing breast carcinoma MDA MB 361 and colon carcinoma WiDr cells (70- to 450-fold) than was previously observed (19- to 27-fold) with 4-[(2-chloroethyl)(2-mesyloxyethyl)amino]benzoyl-L-glutamic acid (CMDA). Prodrug 1 is the most effective antitumor agent in xenografts in mice inoculated with 100% stCPG2(Q)3-expressing MDA MB 361 cells, whereas prodrugs 2 and 3 are most effective when the percentage of stCPG2(Q)3-expressing cells is 50% or 10%. In nude mice bearing xenografts arising from inocula of 100% stCPG2(Q)3-expressing WiDr cells, prodrug 2 is the most effective antitumor agent. All three of the prodrugs produced histological evidence of substantial bystander cell killing in WiDr xenografts in which only 10% or 50% of the cells inoculated were expressing stCPG2(Q)3. We conclude that all three of the prodrugs are more effective therapeutically with stCPG2(Q)3 than is the previously described prodrug CMDA and, also, that the optimal choice of prodrug varies among different tumor types and that prodrugs, optimized for their bystander effect, are effective when only low percentages of cells in a tumor express CPG2. 相似文献
77.
Smith JC Evans LM Wilkinson I Goodfellow J Cockcroft JR Scanlon MF Davies JS 《Clinical endocrinology》2002,56(4):493-501
OBJECTIVES: Hypopituitary adults with growth hormone deficiency (GHD) have an increased cardiovascular mortality, although the mechanisms remain unclear. Endothelial dysfunction, characterized by reduced nitric oxide (NO) bioavailability, is a key early event in atherogenesis and is associated with increased vascular smooth muscle tone and arterial stiffening. DESIGN AND PATIENTS: In a randomized, double-blind, placebo-controlled study, we investigated the effects of GH replacement on endothelial function and large-artery stiffness in 32 GHD adults (19 males, 13 females) (age range 19-64 years) over a 6-month period. Thirty-two age- and sex-matched healthy controls were also studied. MEASUREMENTS: Endothelial function was assessed using ultrasonic wall tracking to measure flow-mediated dilatation (FMD) of the brachial artery. Large artery stiffness was assessed by pulse wave analysis of the radial artery pressure waveform, allowing determination of the corresponding central arterial pressure waveform and derivation of the augmentation index. Fasting lipid profiles, glucose and insulin were also measured. RESULTS: At baseline, FMD (mean +/- SD) was impaired in GH-deficient subjects vs. controls (3.4 +/- 2.3 vs. 5.7 +/- 2.0%, P < 0.0001), although endothelium-independent dilatation was similar. The augmentation index was higher in GH-deficient subjects vs. controls (23 +/- 12 vs. 14 +/- 14%, P < 0.01). GH-deficient subjects had higher LDL cholesterol (4.1 +/- 0.8 vs. 3.5 +/- 0.8 mmol/l, P < 0.01) and lower HDL cholesterol (1.1 +/- 0.3 vs. 1.4 +/- 0.4 mmol/l, P < 0.01). In GH-deficient subjects, there were inverse correlations between LDL cholesterol and FMD (r = -0.40, P < 0.05) and between FMD and the augmentation index (r = - 0.58, P < 0.01). Regression analysis identified FMD as an independent predictor of the augmentation index (P < 0.0001). In comparison with baseline, GH replacement resulted in an increase in FMD (5.0 +/- 2.6 vs. 2.8 +/- 1.9%, P < 0.01). There were decreases in central aortic systolic pressure (117 +/- 15 vs. 123 +/- 17 mmHg, P < 0.01), diastolic pressure (82 +/- 10 vs. 86 +/- 8 mmHg, P < 0.01) and the augmentation index (22 +/- 8% vs. 26 +/- 10%, P < 0.05) despite unchanged brachial pressure indices. LDL cholesterol also decreased (3.5 +/- 0.8 vs. 4.2 +/- 0.8 mmol/l, P < 0.01). There were no significant changes in the placebo group. CONCLUSIONS: Adult GHD is associated with endothelial dysfunction and increased large-artery stiffness. An improvement in endothelial function and a reduction in arterial stiffness following GH replacement suggests an important therapeutic role for GH in reducing cardiovascular risk associated with adult GHD. 相似文献
78.
F Haque ST Fazal SA Ahmad SZ Abbas S Naseem 《Journal of Medical Imaging and Radiation Oncology》2006,50(1):63-65
Primary osteogenic sarcoma of the skull is an exceedingly rare condition. An adult male patient is described, who had a painless swelling in the right forehead that had rapidly enlarged in the previous 6 months. Radiological investigations showed a large destructive mass lesion involving the right side of the frontal bone with extension into the frontal sinus, causing marked extradural compression of brain parenchyma. Histopathological examination confirmed the lesion to be primary osteogenic sarcoma. 相似文献
79.
Expression of differential nitric oxide synthase isoforms in human normal gastric mucosa and gastric cancer tissue 总被引:10,自引:2,他引:10
The present study investigated the expression and distribution of three
isoforms of nitric oxide synthase (NOS) in different anatomical regions of
the human stomach and in gastric neoplastic tissues by immunohistochemistry
using specific antibodies. Intracellular localization of individual
isoenzymes of NOS was detected in normal gastric mucosa. Gastric cancer
tissues had a marked reduction of all three NOS isoforms expression. The
expression of the endothelial NOS, neuronal NOS and inducible NOS in the
tumor tissue was significantly lower than in normal gastric mucosa (P =
0.01, P = 0.02, P < 0.01, respectively). In the tumor tissue the
expression of inducible NOS was significantly lower than the expression of
both constitutive forms of NOS (P < 0.01). There was a tendency to
higher expression of both constitutive forms of NOS in earlier stages T2 of
the tumor compared to advanced T4 tumor. In contrast, the expression of
inducible NOS was higher than in the advanced T4 tumor than in the earlier
stages T2 of the tumor. The mapping of the expression of endothelial NOS,
neuronal NOS and inducible NOS in human stomach showed higher expression of
NOS isoforms in the distal third than in the proximal third of the stomach
(P = 0.03, P = 0.04, P = 0.01, respectively). We conclude that there is
greater expression of NOS in the stomach corpus and in antrum than in the
proximal third of the normal human stomach mirroring the anatomical
predilection of common pathological changes in this part of the human
stomach. Furthermore, there was loss of the expression of individual
isoenzymes in gastric neoplasms.
相似文献
80.
Grasman KA Scanlon PF Fox GA 《Archives of environmental contamination and toxicology》2000,38(2):244-253
The objectives of this study were (1) to describe variation in hematological values found in adult and prefledgling herring
gulls (Larus argentatus) over a large geographic area, (2) to investigate relationships between hematological variables and other physiological indices,
and (3) to examine potential associations between exposure to organochlorines and hematological variables. During 1991–93,
we sampled 160 breeding adult gulls from 13 colonies and 101 4-week-old gulls from 11 colonies. All colonies were in the Great
Lakes ecosystem, except for two colonies on Lake Winnipeg and the Atlantic coast. The hematological values measured in this
study were similar to published values for herring gulls and related species. Significant intersite differences were found
in hematological variables. Sex had little or no influence on leukocyte variables. Adults had lower total leukocyte counts
and higher heterophil to lymphocyte ratios than chicks. PCV was lower in adult females than males. In adults, total leukocyte
and total heterophil numbers were negatively associated with liver activity of ethoxyresorufin-O-deethylase (EROD) and concentrations of highly carboxylated porphyrins (HCPs), two biomarkers of organochlorine exposure.
Total leukocyte and total heterophil numbers were positively associated with liver concentrations of DDE (1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene), and total lymphocytes were associated positively with PCB (polychlorinated biphenyl) and HCP concentrations.
The heterophil to lymphocyte ratio was negatively associated with liver EROD activity and HCPs. In chicks, there was a positive
association between the heterophil to lymphocyte ratio and HG-TEQs (dioxin toxicity equivalents calculated using herring gull–specific
equivalency factors). PCV was associated with some measures of contaminant exposure in adults and chicks. Additional research
is needed to elucidate causal relationships between hematological indices and such factors as contaminants, disease, and nutrition.
Received: 11 March 1999/Accepted: 26 August 1999 相似文献