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91.
Epstein Leonard H.; Temple Jennifer L.; Neaderhiser Brad J.; Salis Robbert J.; Erbe Richard W.; Leddy John J. 《Canadian Metallurgical Quarterly》2007,121(5):877
[Correction Notice: An erratum for this article was reported in Vol 122(1) of Behavioral Neuroscience (see record 2008-01943-025). In the original article, the n values (and corresponding percentages) for the number of people with the A1/A1 & A1/A2 and A2/A2 genotypes were reversed in Table 2. The corrected table appears in the erratum, with the revised numbers appearing in bold font.] The authors measured food reinforcement, polymorphisms of the dopamine D? receptor (DRD?) and dopamine transporter (DAT1) genes, and laboratory energy intake in 29 obese and 45 nonobese humans 18-40 years old. Food reinforcement was greater in obese than in nonobese individuals, especially in obese individuals with the TaqI A1 allele. Energy intake was greater for individuals high in food reinforcement and greatest in those high in food reinforcement with the TaqI A1 allele. No effect of the DAT1 genotype was observed. These data show that individual differences in food reinforcement may be important for obesity and that the DRD? genotype may interact with food reinforcement to influence energy intake. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
92.
EH Hopman FJ Voorhorst P Kenemans CJ Meyer TJ Helmerhorst 《Canadian Metallurgical Quarterly》1995,58(2):206-209
The purpose of this work was to study intraobserver and interobserver variation in the interpretation of colposcopic images of cervical intraepithelial neoplasia (CIN). Twenty-three experienced colposcopists were asked to assess colposcopic images presented on slides and to select the biopsy site. Eleven cases were independently interpreted twice with an interval of 2-3 months by all observers. No information about the cytological classification was available. In each case the "majority assessment" was considered as the standard, being "no CIN" in 2 cases, CIN I in 4 cases, CIN II in 3 cases, and CIN III in 2 cases. Intraobserver concordance was 66.7%, the kappa value was 0.54. Interobserver agreement was found to be 52.4 and 51.0% in the first and second sessions, respectively, while the mean kappa values were 0.41 and 0.33, respectively. In selecting the site for biopsy, 77.4% of all observers agreed while the same site was selected in 85.3% of cases by the individual colposcopist in the two sessions. Overall, CIN I and II interpretations revealed lower levels of agreement than no CIN or CIN III interpretations. It is concluded that observer variability in interpreting colposcopic images and selecting the site for biopsy is in the same range as observer variation in other subjective diagnostic tests such as cytology and histopathology. This variation should be taken into account in the colposcopical management of patients with abnormal cytology. 相似文献
93.
This study examined the relationship of several maternal variables to the duration of exclusive breast-feeding and the total duration of breast-feeding, along with attitudes, perceptions, and beliefs about breast-feeding among women living in poor neighborhoods of Managua, Nicaragua. The field work was carried out in December 1992 and January 1993 using qualitative and quantitative methods. A structured questionnaire was administered in interviews with 556 mothers of children under 12 months of age, and meetings of four directed discussion groups were held, in which a total of 20 women participated. At one week of age, almost all the children of the mothers who were surveyed had been breast-fed, but only 45% had been exclusively breast-fed. At 12 weeks old, 30% were already completely weaned. The discussion groups revealed the coexistence of positive opinions about both breast-feeding and bottle-feeding. However, exclusive breast-feeding was considered harmful for the mother, and breast milk was not thought to be sufficient nourishment for the child. Previous experience was strongly related to the duration of exclusive breast-feeding and to total breast-feeding duration. Attitudes, social support, and work situation were important factors influencing the total length of time women breast-fed a child. In general, the results obtained through the interviews and in the discussion groups were in agreement and showed that the elements needed to promote exclusive breast-feeding were social support, a favorable community environment, and policies that dealt with problems faced by working mothers. The complementary research methods were useful for obtaining information about the relative importance of different factors that determine the duration of breast-feeding and for understanding that practice in greater depth from the mother's point of view. 相似文献
94.
MC Huysmans C Longbottom H Hintze EH Verdonschot 《Canadian Metallurgical Quarterly》1998,32(5):330-336
We investigated the lipid metabolism in primary cultured hepatocytes to elucidate the causes of hyperlipidemia, increased cholesteryl esters, and decreased triglyceride levels in the livers of daunomycin-nephrotic rats. The incorporation of 14C-palmitate into phospholipids and triglycerides in primary cultured hepatocytes and medium was similar in daunomycin-nephrotic and control rats. The incorporation of 14C-acetate into phospholipids, triglycerides, cholesterol, cholesteryl esters, and total fatty acids in primary cultured hepatocytes was increased in daunomycin-nephrotic rats. The radioactivity of phospholipids, triglycerides, cholesterol, cholesteryl esters, and very-low-density lipoprotein lipids in medium was increased in the hepatocytes of daunomycin-nephrotic rats using 14C-acetate as a precursor. The increased cholesterogenesis and the increased secretion of triglycerides synthesized from acetate by hepatocytes may be due to an increased cholesteryl ester content and a decreased triglyceride content in the livers of daunomycin-nephrotic rats. The increased secretion of lipids synthesized from acetate by hepatocytes may be due to increased accumulation of lipids in serum and very-low-density lipoprotein in daunomycin-nephrotic rats. 相似文献
95.
DJ Sugarbaker RM Flores MT Jaklitsch WG Richards GM Strauss JM Corson MM DeCamp SJ Swanson R Bueno JM Lukanich EH Baldini SJ Mentzer 《Canadian Metallurgical Quarterly》1999,117(1):54-63; discussion 63-5
OBJECTIVES: Our aim was to identify prognostic variables for long-term postoperative survival in trimodality management of malignant pleural mesothelioma. METHODS: From 1980 to 1997, 183 patients underwent extrapleural pneumonectomy followed by adjuvant chemotherapy and radiotherapy. RESULTS: Forty-three women and 140 men (age range 31-76 years) had a median follow-up of 13 months. The perioperative mortality rate was 3.8% (7 deaths) and the morbidity, 50%. Survival in the 176 remaining patients was 38% at 2 years and 15% at 5 years (median 19 months). Univariate analysis identified 3 prognostic variables associated with improved survival: epithelial cell type (52% 2-year survival, 21% 5-year survival, 26-month median survival; P =.0001), negative resection margins (44% at 2 years, 25% at 5 years, median 23 months; P =.02), and extrapleural nodes without metastases (42% at 2 years, 17% at 5 years, median 21 months; P =.004). Using the Cox proportional hazards, the relative risk of death was calculated for nonepithelial cell type (OR 3.0, CI 2.0-4.5; P <.0001), positive resection margins (OR 1.7, CI 1.2-2.6; P =.0082), and metastatic extrapleural nodes (OR 2.0, CI 1.3-3.2; P =.0026). Thirty-one patients with 3 positive variables had the best survival (68% 2-year survival, 46% 5-year survival, median 51 months; P =.013). A previously published staging system using these variables stratified survival (P <.05). CONCLUSIONS: (1) Multimodality therapy including extrapleural pneumonectomy is feasible in selected patients with malignant pleural mesotheliomas, (2) pre-resectional evaluation of extrapleural nodes may select patients for radical therapy, (3) microscopic resection margins affect long-term survival, highlighting the need for further investigation of locoregional control, and (4) patients with epithelial, margin-negative, extrapleural node-negative resection had extended survival. 相似文献
96.
A 1 wt% lysozyme solution was used as a model fluid to test a previously formulated mathematical model for the initial chemical reaction fouling rate of a heat transfer surface. The experimental results showed that, at a given wall temperature, a maximum initial fouling rate existed over a range of fluid velocities. The maximum rate and the fluid velocity at which it occurred both increased as the wall temperature increased. These observations were consistent with the model. Quantitatively, the average absolute percent deviation between the experimental results and the optimum model predictions was 23,3%. The decrease in initial fouling rate with increasing velocity at high fluid velocities was even greater than predicted by the model. 相似文献
97.
Thoracotomy patch leads used for implantable cardioverter defibrillators (ICDs) are generally safe and effective. We describe two patients in whom a late complication of patch lead migration occurred years after the original implants, causing a bronchopleural fistula in one and lingular lobe collapse in the other patient. We conclude that patch migration is a late but possible complication of extrapericardial ICD leads, and should be suspected in patients who present with hemoptysis, atypical pneumonia, or lung collapse after the initial ICD surgery. 相似文献
98.
The energy equation was solved exactly for fully developed steady laminar flow in a circular pipe of two immncible Newton liquids with a concentric cylindrical interface between them, assuming invariant physical properties of the liquids, uniform heat flux at the wall and fully developed temperature profiles. It is shown that, even if the viscosity of the annular liquid is orders of magnitude smaller than that of the core liquid, the improvement in heat transfer to the core liquid by infection of the annular liquid cannot exceed a factor of 1 8 相似文献
99.
The hybrid search algorithm for constraint satisfaction problems described here first uses local search to detect crucial substructures and then applies that knowledge to solve the problem. This paper shows the difficulties encountered by traditional and state-of-the-art learning heuristics when these substructures are overlooked. It introduces a new algorithm, Foretell, to detect dense and tight substructures called clusters with local search. It also develops two ways to use clusters during global search: one supports variable-ordering heuristics and the other makes inferences adapted to them. Together they improve performance on both benchmark and real-world problems. 相似文献
100.
The vector form of the Ergun equation was used to numerically predict gas phase streamlines, residence time distributions, chemical conversions and pressure drops in the annulus of a side-outlet spouted bed with an internal draft tube. By varying the position of the side-outlet, it was demonstrated that there exists an optimum location for this outlet at which conversion is a maximum and which shows a greatly improved gas phase residence time distribution in the annulus compared with a conventional spouted bed unit. 相似文献