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991.
Aim: Electrical burns account for up to 10% of burns admissions worldwide. Although a potentially serious mechanism of injury in children, there exists limited Australian data. This study aimed to describe the epidemiology, presentation, management and complications of electrical burn injuries in children. Methods: We performed a retrospective case note review of all children under 16 years of age with electrical burns admitted to the New South Wales Paediatric Burns Centre over an 8‐year, 2‐month study period between November 1995 and December 2003. Results: Twenty‐two cases were identified. The mean age at presentation was 7.6 years (range 8 months to 14.3 years). Eighty‐six percent of cases were sustained from a Low Voltage (<1000 W) power source and 55% occurred in males. The total body surface area burnt ranged from 0.5% to 35% with an average of 4%. Fourteen children had their burns managed non‐operatively, but eight required various surgical procedures ranging from local debridement and primary closure to full‐thickness skin grafting. The average length of hospital stay was 6 days (range 1–58 days). Complications occurred in 4 of the 22 patients (18%) and included wound infections, acute renal failure because of myoglobinuria, permanent electrocardiogram changes and long‐term paraesthesia. Three patients (14%) suffered continued morbidity because of scarring, amputation and psychological disturbance. There was no mortality. Conclusions: Electrical injury was an infrequent but potentially serious cause of injury in children. Minor injuries were successfully managed non‐operatively. Neurological sequelae, cardiac arrhythmias and renal failure remain serious complications in up to 20% of cases.  相似文献   
992.
993.
The detected phenotypes in many diseases are caused from dysfunction in protein-protein, protein-DNA and receptor-ligand interactions. Therefore, determination of these molecular interactions followed by designing or screening the compounds to target these interactions provides a significant challenge in drug development. This review aims to highlight the yeast two-hybrid system in determination of protein-protein interactions and its possible outcomes in pharmaceutical research. The variations of the basic methodology as one- and three-hybrid systems are also disussed in relation to their potential pharmaceutical applications.  相似文献   
994.
CONTEXT: Asthma is ranked as the ninth most common chronic condition in the U.S., and its annual direct costs from hospital services alone are estimated at $3.1 billion. Hospitalization rates due to asthma reveal several disparities and may be attributed to recent changes in the healthcare delivery system, including the penetration of managed care. OBJECTIVE: To examine the relationship between 7-day hospital readmission and insurance provider among adults with asthma. DDESIGN: A retrospective cohort study that included patients aged 18-64 with a principal diagnosis of asthma, who were discharged from acute nonfederal hospitals in New Jersey between 1 January 1993 and 31 December 1996. In the absence of unique patient identifiers, a linkage system was used to match subsequent readmissions for the same patient to the first admission. MMAIN OUTCOME MEASURE: Seven-day readmission. RESULTS: Results showed a significantly increased risk of 7-day readmission for managed care patients as compared to indemnity patients (OR= 1.67, 1.10-2.53). Shorter lengths of stay were associated with greater odds of readmission (LOS=0: OR=5.17, 2.49-10.75, LOS=1: OR=2.30, 1.30-4.07). CONCLUSIONS: Managed care patients have shorter lengths of stay as compared to indemnity patients, which leads to an increased risk of returning to the hospital within a short period of time. In trying to provide cost-effective patient care, we may be discharging patients prematurely.  相似文献   
995.
996.
997.
This study is concerned with the incidence and type of temporal bone anomalies that might be present in persons who, apart from their deafness, are normal. It also attempts to correlate demonstrated abnormalities with the etiology of deafness. Review of the results will permit a reassessment of the value of roentgenographic studies in the routine evaluation of deaf children. One hundred and four deaf students, 3 to 21 years of age, were studied by physical examination, audiometry, and temporal bone tomography. A pertinent history was requested, and appropriate medical records were obtained. Roentgenographically demonstrable abnormalities of the temporal bones were present in 19 students (18%) or 28 temporal bones (13%). Meningitis was the only entity to which a specific pathologic change could be ascribed. The number of abnormalities found in this population was significant and should re-emphasize the importance of temporal bone tomography in the total evaluation of deaf children.  相似文献   
998.
The perturbations of the cytokine signaling pathway play an important role in lymphoid/hematopoietic tumors. Aberrant promoter methylation is the major mechanism of gene silencing in tumors. We examined 150 lymphoid/hematopoietic tumors or potential premalignant specimens, 55 control specimens and 12 EBV-transformed B lymphoblastoid cultures and 10 lymphoma/leukemia (L/L) or multiple myeloma (MM) cell lines for the methylation (and, in cell lines, of the expression status) of three genes involved in the cytokine signaling pathway. The genes were: SHP1, a protein tyrosine phosphatase; SYK, a protein kinase; and SOCS1, a suppressor of cytokine signaling. Our major findings were: (1) one or more of the three genes was frequently methylated in L/L and MM cell lines and there was good concordance (90-100%) between methylation and loss of gene expression; (2) treatment of L/L cell lines with a demethylating agent resulted in re-expression of SHP1 protein and downregulation of phosphorylated STAT3 in L/L cell lines; (3) all 55 control specimens and the lymphoblastoid cultures were negative for methylation of the three genes; (4) non-Hodgkin's lymphomas (100%), and leukemias (94%) had almost universal methylation of SHP1 and relatively less frequent (<30%) methylation of SOCS1 and SYK; (5) MM and monoclonal gammopathy of unknown significance (MGUS) had infrequent methylation of SHP1 (<20%), and occasional methylation of SOCS1 and SYK; and (6) comparable methylation frequencies for SOCS1 were observed in MM and MGUS, suggesting that SOCS1 methylation is an early event in MM pathogenesis. At least one gene was methylated in 119 of 130 (93%) of the malignant and 12 of 20 (60%) of the MGUS samples. Our findings demonstrate that the perturbations of cytokine signaling via silencing of these three genes are almost universal in lymphoid/hematopoietic tumors but the patterns of gene methylated for L/L and plasma cell dyscrasias are different.  相似文献   
999.
Cryptorchism is one of the few well-described risk factors for testicular cancer. It has been suggested that both conditions are related to increased in utero estrogen exposure. The evidence supporting the "estrogen hypothesis" has been inconsistent, however. An alternative hypothesis suggests that higher in utero androgen exposure may protect against the development of cryptorchism and testicular cancer. In order to examine both hypotheses, we studied maternal hormone levels in two populations at diverse risks of testicular cancer; Black Americans (low-risk) and White Americans (high-risk). The study population of 200 mothers of cryptorchid sons and 200 mothers of noncryptorchid sons was nested within the Collaborative Perinatal Project, a cohort study of pregnant women and their children. Third trimester serum levels of estradiol (total, free, bioavailable), estriol, testosterone (total, free, bioavailable), sex hormone-binding globulin, alpha-fetoprotein, and the ratios of estradiols to testosterones were compared between the case and control mothers. The results found no significant differences in the levels of testosterone (total, free, bioavailable), alpha-fetoprotein, sex hormone-binding globulin, or in the ratios of estrogens to androgens. Total estradiol, however, was significantly lower in the cases versus the controls (P = 0.03) among all mothers and, separately, among White mothers (P = 0.05). Similarly, estriol was significantly lower among all cases (P = 0.05) and among White cases (P = 0.05). These results do not support either the estrogen or the androgen hypothesis. Rather, lower estrogens in case mothers may indicate that a placental defect increases the risk of cryptorchism and, possibly, testicular cancer.  相似文献   
1000.
BACKGROUND: We examined the impact of race, education, and household income on changes in rates of discontinuation and initiation of hormone therapy before and after release of the Women's Health Initiative estrogen plus progestin trial results. METHODS: We conducted an observational cohort study of 221 378 women aged 40-80 years enrolled in five health maintenance organizations to estimate the prevalence and rates of discontinuation and initiation of estrogen plus progestin and estrogen only between September 1, 1999, to June 31, 2002 (baseline), and December 31, 2002 (follow-up). We identified the census block group for each participant by geocoding her 2003 residential address. We categorized women into racial, education, and income groups based on the distribution of these characteristics in her community from year 2000 census data and the distributions of these characteristics within her HMO. RESULTS: There were significant differences in estrogen plus progestin and estrogen only prevalence by race, education level, and household income, and in estrogen plus progestin initiation by race and education level, but not by household income at follow-up. However, there were no differences by community race, education, or household income in change in the prevalence of either hormone therapy use at follow-up or in the rates of hormone therapy discontinuation or initiation from baseline to follow-up. CONCLUSIONS: Given the wide spread media attention to the Women's Health Initiative estrogen plus progestin trial results, our findings suggest comparable dissemination of this information across diverse socioeconomic groups.  相似文献   
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