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1.
This paper reviews the evidence of inborn temperament individuality in children, which affects the child-caretaker interaction and can be a source of differential treatment approaches. Focus on the dynamic interaction between individual characteristics and environmental demands views the child as a contributor to his or her own development and parent behavior as often reactive rather than the cause of various childhood disturbances.When this article was written, the author was with the Department of Sociology, Social Work, and Anthropology at Utah State University.  相似文献   
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Stomach cancer is the second cause of death in Mexico in patients with malignant tumors. This disease represents a public health problem. A strong association has been described between chronic infection with Helicobacter pylori and gastric cancer. This malignancy is preceded by a series of preneoplastic conditions, including chronic atrophic gastritis (CAG), intestinal metaplasia (IM), and dysplasia. The objective of this study was to establish the prevalence of preneoplastic conditions associated with infection of Helicobacter pylori in the state of Chiapas and its eradication with antibiotics. Persons infected with Helicobacter pylori and with CAG were identified by serology against CagA protein and serologic levels of gastrin. An endoscopy with biopsy was performed at the beginning of the study, and at 6 weeks and 1 year thereafter. A total of 281 people were enrolled and randomly assigned to treatment or placebo group. CAG was found in 59%, IM in 51%, and dysplasia in 13%. In intent-to-treat and per-protocol analysis, Helicobacter pylori was eliminated in 70 and 76%, respectively. These results indicate high frequency of preneoplastic conditions associated with Helicobacter pylori and an excellent eradication rate. They also offer a possible alternative for preventing gastric cancer.  相似文献   
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PURPOSE: In biopsies of patients with locally advanced breast cancer, we investigated the in vivo changes of the gene expression pattern induced by chemotherapy to find genes that are potentially responsible for the efficacy of the drug. EXPERIMENTAL DESIGN: Early cellular responses to chemotherapy-induced damage, both in vivo and in vitro, were investigated by analyzing chemotherapy-induced changes in gene expression profiles. Core biopsies were taken from nine patients with locally advanced breast cancer, before and at 6 hours after initiation of doxorubicin-based chemotherapy. Both samples were cohybridized on the same microarray containing 18,000 cDNA spots. RESULTS: The analysis revealed marked differences in gene expression profile between treated and untreated samples. The gene which was most frequently found to be differentially expressed was p53 up-regulated modulator of apoptosis (PUMA). This gene was up-regulated in eight of nine patients with an average factor of 1.80 (range, 1.36-2.73). In vitro MCF-7 breast cancer cells exposed to clinically achievable doxorubicin concentrations for 6 hours revealed marked induction of PUMA mRNA, as well. CONCLUSIONS: This is the first report describing PUMA mRNA to be up-regulated as a response to chemotherapy in patients. Because PUMA is a known member of the family of BH3-only proapoptotic proteins, this finding suggests PUMA's potential importance for the response to anticancer drugs.  相似文献   
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Obesity and overweight are established risk factors for the development of breast cancer. They are also associated with poor prognosis for higher risk of disease recurrence and lower overall survival (OS). The aim of this study was to evaluate the influence of overweight and obesity in OS in patients with locally advanced breast cancer (LABC) treated with neoadjuvant chemotherapy. This is a retrospective analysis that included 819 patients diagnosed with LABC between January 2004 and December 2008. The patients were treated with neoadjuvant chemotherapy (NAT) based on anthracyclines, taxanes, or both, followed by surgery. For comparison, patients were divided into the normal weight (NW) group or the overweight/obesity (OW/OB) group. The prevalence of overweight/obesity was 74 %. General characteristics of the patients, including age, tumor size, clinical stage, nuclear grade, hormone receptors, and HER2 expression, were similar between both groups. At a median follow-up of 28 months, we found a statistically significant difference in OS between the two groups, achieving a 91.5 % in NW patients versus 85.9 % in the OW/OB group (P = 0.050). Cox multivariate analysis demonstrated that obesity was an independent factor for poor prognosis, with a hazard ratio of 1.79 (95 % CI (Confidence Interval) 1.09–2.96; P = 0.022). This is the first Mexican study that confirms the role of OW/OB as a risk factor for poor outcome among patients with LABC. Obesity in our country is a public health problem and requires strong preventive intervention strategies for its control, especially among patients diagnosed with breast cancer.  相似文献   
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Background: Dobutamine stress echocardiography (DSE) is commonly used for the diagnosis for coronary artery disease (CAD). We previously demonstrated that squatting induces wall motion abnormalities (WMA) in areas subtended by stenotic coronary arteries. Objective: This study was designed to test the hypothesis that dobutamine and squatting stress echocardiography are equally useful for the diagnosis of CAD. Methods: We studied 39 patients who were scheduled to have coronary angiography for the evaluation of chest pain. Each patient had squatting stress echocardiography followed by DSE. For squatting stress echocardiography the echocardiogram in standard views was recorded in the standing position. The procedure was repeated during squatting for 2 minutes. Dobutamine echocardiography was performed using standard protocol. The squatting and dobutamine stress echocardiograms were interpreted by an observer blinded to the results of coronary angiography. Results: During squatting, new or worsening WMA developed in 20 patients. Six patients developed WMA in the left anterior descending artery territory, three in circumflex territory, three in the right coronary artery territory, and eight in multiple coronary territories. The sensitivity, specificity, and accuracy of squatting echocardiography for diagnosis of CAD were 95%, 94%, and 94%, respectively. For DSE, the sensitivity, specificity, and accuracy for the diagnosis of CAD were 85%, 94%, and 90%, respectively. There was no significant difference between squatting and dobutamine stress echocardiography for the diagnosis of CAD (P = 0.702). Conclusion: These data indicate that squatting and dobutamine echocardiography are equally useful in the diagnosis of CAD. In selected patients, squatting echocardiography may be used in place of dobutamine echocardiography for the diagnosis of CAD. (Echocardiography 2012;29:695–699)  相似文献   
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Exposure of mouse cerebellar granule neurons (CGNs) to domoic acid induced cell death, either by apoptosis or by necrosis, depending on its concentration. Necrotic damage predominated in response to domoic acid above 0.1 microM. In contrast, cell injury with apoptotic features (assessed by Hoechst staining and DNA laddering assay) was evident after exposure to lower concentrations of domoic acid (< or = 0.1 microM). The AMPA (alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid)/kainate receptor antagonist 2,3-dihydroxy-6-nitro-sulfamoylbenzo [f] quinoxaline, but not the N-methyl-D-aspartate receptor antagonist MK-801, prevented domoic acid-induced apoptosis. To evaluate the role of oxidative stress in domoic acid-induced apoptosis, experiments were carried out in CGNs isolated from wild-type mice (Gclm (+/+)) and mice lacking the modifier subunit of glutamate-cysteine ligase, the first and rate-limiting step of glutathione (GSH) biosynthesis (Gclm (-/-)). CGNs from Gclm (-/-) mice have very low levels of GSH and were more sensitive to domoic acid-induced apoptosis and necrosis than Gclm (+/+) CGNs. The antioxidant melatonin (200 microM) and the membrane-permeant GSH delivery agent GSH ethyl ester (2.5 mM) prevented domoic acid-induced apoptosis. Domoic acid increased formation of reactive oxygen species but did not affect intracellular GSH levels. Domoic acid also increased cytosolic and mitochondrial calcium levels, increased oxidative stress in mitochondria, and altered mitochondrial membrane potential, which ultimately caused cytochrome c release, activation of caspase-3, and degradation of poly (ADP-ribose) polymerase. These results indicate that low concentrations of domoic acid cause apoptotic neuronal cell death mediated by oxidative stress.  相似文献   
9.
OBJECTIVES: To quantify the surgical infection rate and to identify risk factors associated with surgical site infection. METHODS: We conducted a case-control study of all surgical patients between January 1, 1993, and June 30, 1994. The frequency of surgical site infection per 100 surgeries was calculated. The odds ratio (OR) was estimated by using logistic regression analysis. SETTING: A 130-bed tertiary-care teaching hospital for adult patients with cancer. RESULTS: The study followed 3372 surgeries. Three hundred thirteen patients had a surgical site infection (rate per 100 surgeries: 9. 30). The risk factors associated with surgical site infection were diabetes mellitus (OR = 2.5, 95% confidence interval [CI] = 1.27-4. 91), obesity (OR = 1.76, 95% CI = 1.14-2.7), presence of surgical drains for >5 and <16 days (OR = 1.84, 95% CI = 1.02-3.31), and presence of surgical drains for >/=16 days (OR = 2.14, 95% CI = 1. 0-4.6). The bacteria most frequently isolated were Escherichia coli 38 (21.8% of the total of microorganisms found), Pseudomonas sp 22 (12.6%), Staphylococcus aureus 16 (9.2%), and coagulase-negative Staphylococcus 25 (13.6%). The coexistence of other nosocomial infections was greater among the cases (OR = 1.8, 95% CI = 1.1-3.1) than in the control group. CONCLUSIONS: The surgical site infection rate in our hospital is slightly higher than the rates reported for general hospitals. The risk factors associated with surgical site infection are similar to those previously reported. Diabetes mellitus, obesity, and prolonged presence of a surgical drain increased the risk of infection.  相似文献   
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