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1.
This study examined differences between 3 matched samples of White (n?=?2,306) and African American (n?=?2,306), White (n?=?1,176) and Hispanic (n?=?1,176), and White (n?=?466) and Asian (n?=?466) children on the Naglieri Nonverbal Ability Test (NNAT; J. A. Naglieri, 1997a). The groups were selected from 22,620 children included in the NNAT standardization sample and matched on geographic region, socioeconomic status, ethnicity, and type of school setting (public or private). There was only a small difference between the NNAT scores for the White and African American samples (d ratio?=?.25) and minimal differences between the White and Hispanic (d ratio?=?.17) and between the White and Asian (d ratio?=?.02) groups. The NNAT was moderately correlated with achievement for the total sample and correlated similarly with achievement for the White and ethnic minority groups. The median correlation of NNAT with reading was .52 and NNAT with math was .63 across the samples. Results suggest that the NNAT scores have use for fair assessment of White and minority children. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

2.
Adults with autosomal dominant polycystic kidney disease (ADPKD) who have overt proteinuria (>300 mg/d) have higher mean arterial pressures, lower creatinine clearances, larger renal volumes, and a more aggressive course of renal disease than ADPKD patients without proteinuria. This study examines the relationship between proteinuria and microalbuminuria and similar factors in ADPKD children. A total of 189 children from 81 ADPKD families was included in the analysis. The ADPKD children (n = 103) had significantly greater urine protein excretion rates than the non-ADPKD children (n = 86) (3.9+/-0.3 versus 2.8+/-0.2 mg/m2 per h, P < 0.001). Children with severe renal cystic disease (> 10 cysts; n = 54) had greater protein excretion than those with moderate disease (< or = 10 cysts; n = 49) (4.4+/-0.5 versus 3.3+/-0.2 mg/m2 per h, P < 0.05). The ADPKD children had significantly greater albumin excretion rates than the non-ADPKD children (32+/-6 versus 10+/-2 mg/m2 per 24 h, P < 0.001), and a higher percentage of ADPKD children had significant microalbuminuria (>15 mg/m2 per 24 h in boys and >23 mg/m2 per 24 h in girls) than their unaffected siblings (30% versus 10%, P < 0.05). Thirty percent of ADPKD children had albuminuria and 23% had overt proteinuria. For all ADPKD children, there was no correlation between proteinuria and hypertension. However, there was a significant correlation between urinary protein excretion and diastolic BP among children diagnosed after the first year of life (r = 0.23, P < 0.05). Therefore, proteinuria and albuminuria occur early in the course of ADPKD and may be markers of more severe renal disease.  相似文献   

3.
Hematocrits (PCV) were measured at 29 and 106 d of age (PCV1 and PCV2, respectively) in male and female White Plymouth Rocks. Four lines were used, two of which had undergone 40 generations of divergent selection for 8-wk BW (HWS, LWS), and two respective sublines (HWR, LWR), in which selection had been relaxed for five generations. At both ages, males and females did not differ for PCV in lines HWR, LWR, and LWS. For line HWS there was an age by sex interaction that resulted from an age effect for males but not for females, and from a sex effect at each age. At both ages, PCV was higher for the HW than the LW lines. Initially, there was no difference between the selected and their respective relaxed lines, but by 106 d, HWR chickens had a higher PCV than HWS chickens. In lines HWR and LWR, PCV increased with age. There was a negative correlation in HWS males for PCV1 with 28 and 56 d BW. The HWR males also had a negative correlation for PCV1 with BW at 28 d, but not between PCV2 and BW. The correlation for PCV1 with PCV2 was high and positive for HWR males and females.  相似文献   

4.
A study on the venom yield of snakes from Argentina over a three year period was carried out on adult specimens of Bothrops alternatus (n = 74); Bothrops neuwiedii (n = 127); Bothrops ammodytoides (n = 30); Bothrops moojeni (n = 14); Bothrops jararaca (n = 14); B. jararacussu (n = 6); Crotalus durissus terrificus (n = 120) and Micrurus spp. (n = 6) as well as with 12 specimens of newborn C. d. terrificus kept in captivity. While for each species there was a positive correlation between venom yield and number of snakes milked, the correlation with the snake's body weights after individual milkings was even better, suggesting that the size of the snakes is more important in determining the venom yield than the number of snakes milked or the specimen's sex. Individual milkings indicated that, in addition to the snake size, when the amount of venom is normalized per 100 g body weight there is a species specific difference in venom yield. It follows the order B. jararacussu > B. moojeni approximately = B. jararaca approximately = B. alternatus > B. neuwiedii> Micrurus spp approximately = B. ammodytoides> C. d. terrificus. Although the venom yield per 100 g body weight of newborn C. d. terrificus specimens is 2-fold higher than that of adults, no correlation was observed between venom yield and body weight.  相似文献   

5.
A systematic study of the microstructure/fracture toughness/processing correlation of metal-ceramic composites in the Ti-B-Cu porosity system is presented. The composites are produced by the combustion synthesis process. Fracture surfaces indicate both ductile and brittle regions. The composites are made up of Ti as the only ductile phase and TiB, TiB2, Ti2Cu, and Ti3Cu4 as brittle phases. Density measurements and scanning electron microscopy (SEM) indicate that the samples contain distributed porosity. Ductile phase toughening is responsible for the increase in fracture toughness to a maximum value of 9.9 MPa(m)1/2. Samples with large amounts of porosity do not benefit from this toughening process even though they containin situ formed whiskers. The fracture toughness of the composite is modeled by considering the additive influence of the ductile phase reinforcement (Ashby model) and the residual porosity (exponential model). Microstructural constants required for the model are evaluated from the comparison. A correlation between the mechanical properties and the combustion temperature is established. Formerly with the Department of Materials Science and Engineering, University of Cincinnati  相似文献   

6.
Previous analyses have suggested that the database of 755 studies of the validity of the General Aptitude Test Battery (GATB) demonstrates a small but consistent positive correlation with criteria relevant to job performance. Critics have noted that some of the validity studies conducted were not included in the database and have speculated that these studies may have found negligible or even negative validities, so that the extant database is subject to selection bias. The authors use a mathematical model to estimate the magnitude of possible selection and its effects on the mean and variance of GATB validities. Although evidence of selection is found for some GATB scales and composites, the estimated effect of selection is probably too small to influence conclusions about the validity of the GATB. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

7.
Facial composite research has generally focused on the investigative utility of composites—using composites to find suspects. However, almost no work has examined the diagnostic utility of facial composites—the extent to which composites can be used as evidence against a suspect. For example, detectives and jurors may use the perceived similarity of a suspect to a composite as evidence to determine the likelihood of a suspect's guilt. However, research in social cognition and models of cognitive coherence suggest that these similarity judgments may be biased by evaluators' preexisting beliefs of guilt. Two studies examined how preexisting beliefs of guilt influence similarity ratings between a suspect and a facial composite. Study 1 (n = 93) demonstrated that mock-investigators' beliefs in a suspect's guilt inflated their subsequent similarity ratings. Study 2 (n = 49) demonstrated that mock-jurors' beliefs in a defendant's guilt predicted their similarity ratings. These findings highlight a problem of using facial composites as evidence against a suspect, and demonstrate the malleability of similarity judgments. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

8.
We tested the efficacy of an estrus control system designed to provide optimal control of follicular development. In Exp. 1, postpartum cows (n = 133) and yearling heifers (n = 57) were fed either .5 mg x female(-1) x d(-1) of melengestrol acetate (MGA) or the carrier for MGA from d -13 to d 0 (d 0 = last day of MGA feeding). All females received 25 mg of PGF2alpha (i.m.) on d -13 and 0. On d -6, cows and heifers fed MGA were administered an i.m. injection of progesterone (200 mg; MGA/P4), and those fed the corn carrier (2XPGF2alpha) received no progesterone. Beginning on d 1, females were bred by AI from d 1 to at least d 5. During the estrus synchronization period (d 1 to d 5), more (P < .05) postpartum cows were observed in estrus (70.1 vs 42.4%), the timing of estrus was more (P < .05) precise, conception rate was similar, and pregnancy rate was higher (P < .05) in the MGA/P4 than in the 2XPGF2alpha treatment. More (P < .05) cows that were anestrous at the beginning of the breeding season were in estrus during the synchronization period in the MGA/P4 (55.8%) than in the 2XPGF2alpha (28.6%) treatment. In heifers, estrus was synchronized in over 90% of females, and neither conception nor pregnancy rate during the synchronization period differed between treatments. In Exp. 2, postpartum cows (n = 122) and heifers (n = 84) received treatments (MGA/P4 or 2XPGF2alpha) as described for Exp. 1 with one exception. In the MGA/ P4 treatment, progesterone was administered on d -7 rather than d -6. Females were bred by AI from d 1 to 5. The estrus response and conception rate during the synchronization period did not differ between treatments for either cows or heifers. We conclude that the progestin-based estrous synchronization system used in this study effectively synchronized an estrus of normal fertility in cyclic cows and induced a majority of anestrous cows to reinitiate estrous cycles.  相似文献   

9.
The authors propose a procedure to determine (a) predictor composites that result in a Pareto-optimal trade-off between the often competing goals in personnel selection of quality and adverse impact and (b) the relative importance of the quality and impact objectives that correspond to each of these trade-offs. They also investigated whether the obtained Pareto-optimal composites continue to perform well under variability of the selection parameters that characterize the intended selection decision. The results of this investigation indicate that this is indeed the case. The authors suggest that the procedure be used as one of a number of potential strategies for addressing the quality-adverse impact problem in settings where estimates of the selection parameters (e.g., validity estimates, predictor intercorrelations, subgroup mean differences on the predictors and criteria) are available from either a local validation study or meta-analytic research. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

10.
High-volume-fraction SiC-Al-based composites have been fabricated by squeeze casting. The effect of particle-size distribution and squeeze-cast parameters on the metal-matrix composites (MMCs) was investigated. The results showed that bulk density of the composites was 2.855 to 3.067 g/cm3 with the various component mixtures of SiC particulates, i.e., the SiC volume fraction was 51.6 to 74.4 pct. The young’s modulus of the composites was between 220 and 226 GPa. The maximum four-point bending strength and fracture toughness reached 478 MPa and 9.42 MPa(m)−1/2, respectively. The coefficient of thermal expansion (CTE) of the composites was from 5 to 8 × 10−6/K, depending on the volume fraction of SiC.  相似文献   

11.
1. Reference values for the plasma creatinine were established using the alkaline picrate method with the Greiner Selective Analyzer GSA II in relation to the Cr 51-EDTA Clearance. Individuals with normal GFR between 93 to 159 ml/min/1.73 m2 had creatinine values in men (n = 65) from 53.7 to 119.5 mumol/l (0.61 to 1.35 mg/100 ml) and in women (n = 59) from 37.7 to 107 mumol/l (0.42 to 121 mg/100 ml). 2. The creatine determinations with the GSA II were compared to those on the Technicon Analyzer, the Beckman Creatinine Analyzer, the Gemsaec-Fast Analyzer and to the enzymatic creatinine method. A good correlation (r = 0.9780-0.984) was observed. 3. With the GSA II and the enzymatic method, bilirubin showed a minor interference which was more marked with the Beckman analyzer.  相似文献   

12.
Describes 2 studies with 41 and 20 undergraduates, respectively, on the self-peer rank of need for achievement (n Ach) and correlation with academic success. It was found that (a) when Ss use their peers as reference points, they are able to give self-reports of their levels of n Ach which are predictive of academic success; (b) these judgments of motivation are independent of achievement-success information; (c) when Ss are given a common standard, the level of accuracy of the predictions is higher than reported previously; and (d) the correlations between judgments of motivation and measures of performance are relatively independent of correlations between measures of ability and measures of performance. It is concluded that n Ach is not, as traditionally considered, an unconscious characteristic and that the self-peer rank method may be a useful adjunct to assessment procedures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

13.
BACKGROUND: The outcome of the Fontan operation largely depends on the selection of patients because this procedure is a physiological correction. Among the several selection criteria for the Fontan operation, the importance of adequate size of the pulmonary artery remains controversial. In this series, in order to clarify whether the pulmonary artery size is indispensable or not as one of the selection criteria for the Fontan operation, we considered the physiological meaning of pulmonary artery size and investigated how it influenced postoperative hemodynamics of the Fontan operation. METHODS AND RESULTS: In congenital heart disease of decreasing pulmonary blood flow, 40 patients were examined for this analysis. Pulmonary artery indexes (cross-sectional area of the right and left pulmonary arteries divided by body surface area) were measured as the expression of pulmonary artery size, and the relations of pulmonary artery index (PAI) to pulmonary vascular resistance (Rp) and compliance (Cp) were studied. There was no significant correlation between PAI and Rp, whereas a significant correlation was found between PAI and Cp (r = .71, P = .001). Furthermore, Cp influenced postoperative hemodynamics of the Fontan operation by affecting the peak central venous pressure (pCVP) and total impedance, which was the afterload to the ventricle. Impedance increased abruptly when PAI was < approximately 100 mm2/m2. CONCLUSIONS: The smaller pulmonary artery size causes more disadvantageous hemodynamics after the Fontan operation, with resultant effects of the rise in pCVP and the increase in afterload to the single ventricle.  相似文献   

14.
Leptin is the protein product of the ob gene, an adipocyte-specific gene, recently discovered in mice. Plasma leptin levels were determined in six normals, twenty-one subjects with impaired glucose tolerance, and forty-nine untreated NIDDM subjects. They increased with the augmentation of obesity (body mass index, BMI kg/m2) and were higher in females than in males: in BMI less than 25 kg/m2 the values of plasma leptin were 2.24 +/- 0.25 ng/ml (n=29) in males and 3.01 +/- 0.39 ng/ml (n=13) in females (P<0.054), respectively, in BMI between 25 kg/m2 and 30 kg/m2 they were 3.14 +/- 0.31 ng/ml (n=10) in males and 10.66 +/- 2.86 ng/ml (n=7) in females (P<0.0018) and in BMI higher than 30 kg/m2 their levels were 8.98 +/- 1.5 ng/ml (n=11) and 11.74 +/- 2.2 ng/ml (n=6) (P<0.23), respectively. The severity of diabetes mellitus judged from the fasting plasma glucose level had no influence on the plasma leptin levels during OGTT, but the leptin levels decreased significantly during a tolerance test (P<0.001), and similar results were also seen during a breakfast test. The fasting plasma leptin in the male with FBS less than 140 mg/dl had a significant correlation with the fasting plasma IRI level, but this correlation disappeared after taking obesity into consideration. Thus the plasma leptin was chiefly dependent on the body weight and gender and had no special relation to diabetic severity.  相似文献   

15.
PURPOSE: To determine the toxicities, pharmacokinetics, and recommended doses of the topoisomerase I inhibitor, topotecan, in patients with varying degrees of renal excretory dysfunction. PATIENTS AND METHODS: Fourteen patients with normal renal function [creatinine clearance (CrCl) > or = 60 mL/min] and 28 patients with varying degrees of renal dysfunction were treated with topotecan 0.4 to 2.0 mg/m2/d as a 30-minute infusion for 5 consecutive days every 3 weeks. Plasma and urine samples were obtained to determine the disposition of topotecan. RESULTS: In patients with mild renal dysfunction (CrCl = 40 to 59 mL/min), dose-limiting hematologic toxicity was observed in three of eight patients receiving topotecan 1.0 mg/m2/d and in two of five patients receiving topotecan 1.5 mg/m2/d. In patients with moderate renal dysfunction (CrCl = 20 to 39 mL/min), dose-limiting hematologic toxicity was observed in three of eight patients who received topotecan 0.5 mg/m2/d, and in two of four patients receiving topotecan 1.0 mg/m2/d; these events were more frequently observed in extensively pretreated patients. Pharmacokinetic analyses showed significant correlations between CrCl and the plasma clearance of both total topotecan [Spearman's correlation coefficient (r2) = 0.65, P = .00001] and topotecan lactone (r2 = 0.65, P = .00003). Mean systemic plasma clearance of total topotecan was significantly reduced in patients with mild (P = .04) and moderate (P = .00006) renal dysfunction. There was no evidence of changes in the pharmacodynamic relationship between topotecan exposure (AUC) and myelotoxicity. CONCLUSION: Dose adjustments are required in patients with moderate, but not mild, renal impairment. For patients with moderate renal dysfunction, the recommended starting dose of topotecan is 0.75 mg/m2/d for 5 days every 3 weeks. Moreover, extensively pretreated patients need further dose reductions.  相似文献   

16.
Investigated the use of an elaborative process by young children in the performance of verbally presented arithmetic addition problems of the form m?+?n?=?——. Kindergartners at 3 developmental levels of number conservation performed best under concrete-plus-verbal prompt condition. When performance on items where m?>?n was compared with m?n, conservers and nonconservers performed differently under an imaginal-plus-verbal as compared to a verbal-only prompt condition. A static rather than dynamic verbally described relation between stimulus sets resulted in more correct responses for 2 of 9 developmental level?×?prompt condition groups. The results suggest that an elaborative process may be used by kindergarten children in the solution of addition word problems. (31 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

17.
Conditions favoring left-handed Z-DNA such as high salinity (> 4 ), high negative DNA supercoiling, and GC-rich DNA [statistically favoring d(CG)n repeat sequences], are all found in the extremely halophilic archaeum (archaebacterium) Halobacterium halobium. In order to identify and study Z-DNA regions of the H. halobium genome, an affinity chromatography method with high Z-DNA selection efficiency was developed. Supercoiled plasmids were incubated with a Z-DNA-specific antibody (Z22) and passed over a protein A-agarose column, and the bound plasmids were eluted using an ethidium bromide gradient. In control experiments using mixtures of pUC12 (Z-negative) and a d(CG)5-containing (Z-positive) pUC12 derivative, up to 4,000-fold enrichment of the Z-DNA-containing plasmid was demonstrated per cycle of the Z-DNA selection procedure. The selection efficiency was determined by transformation of Escherichia coli DH5alpha with eluted plasmids and blue-white screening on X-gal plates. Twenty recombinant plasmids containing Z-DNA-forming sequences of H. halobium were isolated from a genomic library using affinity chromatography. Z-DNA-forming sequences in selected plasmids were identified by bandshift and antibody footprinting assays using Z22 monoclonal antibody. Alternating purine-pyrimidine sequences ranging from 8 base pairs (bp) to 13 bp with at least a 6-bp alternating d(GC) stretch were found in the Z22 antibody binding regions of isolated plasmids. The distribution of Z-DNA-forming sequences in the Halobacterium salinarum GRB chromosome was analyzed by dot-blot hybridization of an ordered cosmid library using the cloned H. halobium Z-DNA segments as probe. Among the 11 Z-DNA segments tested, five were found to be clustered in a 100-kilobase pair region of the genome, whereas six others were distributed throughout the rest of the genome.  相似文献   

18.
The immune-mediated graft-versus-leukemia effect is important to prevent relapse after allogeneic progenitor cell transplantation. This process requires engraftment of donor immuno-competent cells. The objective of this study was to assess the feasibility of achieving engraftment of allogeneic peripheral blood or bone marrow progenitor cell after purine analog containing nonmyeloablative chemotherapy. Patients with advanced leukemia or myelodysplastic syndromes (MDS) who were not candidates for a conventional myeloablative therapy because of older age or organ dysfunction were eligible. All patients had an HLA-identical or one-antigen-mismatched related donor. Fifteen patients were treated (13 with acute myeloid leukemia and 2 with MDS). The median age was 59 years (range, 27 to 71 years). Twelve patients were either refractory to therapy or beyond first relapse. Eight patients received fludarabine at 30 mg/m2/d for 4 days with idarubicin at 12 mg/m2/d for 3 days and ara-c at 2 g/m2/d for 4 days (n = 7) or melphalan at 140 mg/m2/d (n = 1). Seven patients received 2-chloro-deoxyadenosine at 12 mg/m2/d for 5 days and ara-C 1 at g/m2/d for 5 days. Thirteen patients received allogeneic peripheral blood stem cells and 1 received bone marrow after chemotherapy. Graft-versus-host disease (GVHD) prophylaxis consisted of cyclosporine and methyl-prednisolone. Treatment was generally well tolerated, with only 1 death from multiorgan failure before receiving stem cells. Thirteen patients achieved a neutrophil count of greater than 0.5 x 10(9)/L a median of 10 days postinfusion (range, 8 to 17 days). Ten patients achieved platelet counts of 20 x 10(9)/L a median of 13 days after progenitor cell infusion (range, 7 to 78 days). Eight patients achieved complete remissions (bone marrow blasts were < 5% with neutrophil recovery and platelet transfusion independence) that lasted a median of 60 days posttransplantation (range, 34 to 170+ days). Acute GVHD grade > or = 2 occurred in 3 patients. Chimerism analysis of bone marrow cells in 6 of 8 patients achieving remission showed > or = 90% donor cells between 14 and 30 days postinfusion, and 3 of 4 patients remaining in remission between 60 and 90 days continued to have > or = 80% donor cells. We conclude that purine analog-containing nonmyeloablative regimens allow engraftment of HLA-compatible hematopoietic progenitor cells. This approach permits us to explore the graft-versus-leukemia effect without the toxicity of myeloablative therapy and warrants further study in patients with leukemia who are ineligible for conventional transplantation with myeloablative regimens either because of age or concurrent medical conditions.  相似文献   

19.
采用真空热压法在不同温度下制备了体积分数为12%的WCp/2024Al复合材料,试验中所用WC原始粉末的平均粒径分别为2μm和8μm.利用XRD、SEM、EDS等方法对增强颗粒与基体金属之间的界面反应进行了研究.结果表明,界面反应的主要产物为WAl12,但是当制备温度较高时,界面反应产物中出现少量Al5W,并且WCp(2μm)/2024Al复合材料界面反应的起始温度低于WCp(8μm)/2024Al复合材料.硬度测试结果表明,界面反应发生后,复合材料的硬度提高,最高比例达50%.  相似文献   

20.
Although not an AIDS-defining malignancy, anal cancer is an evolving problem in HIV-infected patients. Treatment-tolerance to radiotherapy as well as to chemotherapy is supposed to be reduced in patients with HIV-infection. From January 1995 to January 1997, four patients with epidermoid cancer of the anal canal and a long history of HIV-infection but without symptoms of AIDS or repeated severe infections were treated with radiotherapy (n = 1) or radiochemotherapy (n = 3). External beam radiotherapy with 45 Gy to the tumor and pelvic as well as inguinal lymphatic drainage was administered. In tumors larger than T2 N0 lesions an additional boost of 9 Gy was given. Chemotherapy consisted of 5-fluorouracil 1000 mg/m2/24 h, d 1-4 two cycles and Mitomycin C either 1 x 15 mg/m2, d 1 in the first, or 2 x 10 mg/m2, d 1, in the first and fifth week of radiotherapy. Acute reactions were mild to moderate in all patients and all but one treatment could be given as scheduled (1 patient with a delay of 4 days). No excessive acute reactions were seen. Because of the short follow-up, late reactions and local control are not yet evaluable.  相似文献   

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