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81.
Lichtman R Varney Burst H Campau N Carrington B Diegmann EK Hsia L Thompson JE 《Journal of Midwifery & Women's Health》2003,48(6):455-463
A group of expert educators, each with more than 20 years of experience in midwifery education, was asked to contribute a "pearl (or pearls) of wisdom" for clinical teaching. Despite minimal instructions regarding what type of wisdom was being solicited, remarkable similarities emerged from the educators' contributions. Themes included the need for self-evaluation to become a competent preceptor, the role-modeling function of the preceptor, the development of critical thinking in students, the need to appreciate students' varying learning styles and individual ways of functioning, and the use of positive reinforcement. Although these may seem like universally accepted concepts in clinical teaching, one contributor related stories she heard from students about "hazing" behaviors that have a negative impact on learning. This points to the need for ongoing education about being an educator, another theme echoed in several of the contributions. 相似文献
82.
K S Wong T Y Lin Y C Huang S H Hsia P H Yang S M Chu 《Archives of disease in childhood》2002,87(4):312-315
AIMS: To review the clinical presentation, radiographic findings, and outcome of therapy in children with septic pulmonary embolism. METHODS: Retrospective analysis of patients in a tertiary paediatric facility in northern Taiwan. RESULTS: Ten children were identified with septic pulmonary emboli in a four year retrospective chart review between 1998 and 2001. Seven were immunocompetent, two were premature infants, one had beta thalassemia major. Seven had community acquired staphylococcal infections and bacteraemia, of which six were methicillin resistant Staphylococus aureus (MRSA) isolates. Five had soft tissue infections, two bone infections, one suppurative otitis media, one catheter related infection, and one unknown foci of infection. Multiple and bilateral nodular pulmonary parenchymal lesions were common on plain chest radiographs, but chest computed tomography scans showed the additional findings of a "vessel sign" and central cavitations, confirming the existence of septic pulmonary embolism. CONCLUSIONS: Community acquired MRSA infections occurred in seven patients with septic pulmonary embolism but without predisposing high risk factors. Critically ill children with skin, soft tissue, or bone infections, when associated with septic pulmonary embolism in an area with a high rate of MRSA, should be empirically treated with glycopeptides (such as vancomycin or teicoplanin) before susceptibility results are known, in order to minimise morbidity and avoid mortality. 相似文献
83.
Curcumin decreases the DNA adduct formation,arylamines N-acetyltransferase activity and gene expression in human colon tumor cells (colo 205) 总被引:1,自引:0,他引:1
The effects of curcumin on the N-acetyltransferase (NAT) activity, AF-DNA adduct formation and NAT gene expression were examined using the human colon tumor cell line (colo 205). Various concentrations of curcumin were added to the cytosols or to the medium of human colon tumor cells. The NAT activity was determined by high performance liquid chromatography assaying for the amounts of acetylated 2-aminofluorene (AAF) and p-aminobenzoic acid (N-Ac-PABA) and nonacetylated 2-aminofluorene (AF) and p-aminobenzoic acid (PABA). The NAT activity in the human colon tumor cells and cytosols was suppressed by curcumin in a dose-dependent manner. The results demonstrated that gene expression (NAT1 mRNA) in human colon tumor cells was inhibited by curcumin. The apparent values of Km and Vmax of NAT of human colon tumor cells were also decreased by curcumin in cytosols. Curcumin may act as a noncompetitive inhibitor. After the incubation of human colon tumor cells with AF with or without curcumin cotreatment, the cells were recovered and DNA was prepared, hydrolyzed to nucleotides, the adducted nucleotides were extracted into butanol and AF-DNA adducts analyzed by HPLC. The results also demonstrated that when curcumin was added to the media a decrease in AF-DNA adduct formation was seen in the human colon tumor cells. The finding of AF-DNA adduct formation in cultured human colon tumor cells suggests the usefulness of cultured cells for assessing arylamine-induced DNA damage. 相似文献
84.
BACKGROUND: The effects of paclitaxel on the in vivo distribution and the levels of N-acetylation of 2-aminofluorene (AF) and AF-DNA adducts in Sprague-Dawley (SD) rats were studied. METHODS AND RESULTS: For in vivo examination, pretreatment with paclitaxel (50 mg/kg) 48 hours prior to the administration of AF (50 mg/kg) resulted in a 28% and 43% decrease, respectively, in the urinary and fecal recovery of N-acetyl-2-aminofluorene (AAF), and a 22% decrease in the metabolic clearance of AF to AAF. Paclitaxel did not affect the Michaelis-Menten parameters for N-acetyltransferase (NAT) activity in blood, liver, lung, colon and bladder. Similarly, the Km value for AF in the examined tissues was not affected by paclitaxel. However, the Vmax value estimate of liver NAT activity was significantly decreased after paclitaxel pretreatment. Following exposure of rats to AF with and without pretreatment with paclitaxel, DNA-AF adducts were examined in the target tissues, liver, colon and bladder, and also in non-target tissues, lung and circulating leukocytes. The DNA-AF adducts in the liver, bladder, lung, colon and leukocytes were decreased by pretreatment with paclitaxel. CONCLUSION: This is the first finding to show that paclitaxel affects AF distribution and N-acetylation and DNA adduct in SD rats in vivo. 相似文献
85.
Genotypic analysis of esophageal squamous cell carcinoma by molecular cytogenetics and real-time quantitative polymerase chain reaction 总被引:4,自引:0,他引:4
Yen CC Chen YJ Lu KH Hsia JY Chen JT Hu CP Chen PM Liu JH Chiou TJ Wang WS Yang MH Chao TC Lin CH 《International journal of oncology》2003,23(4):871-881
We performed an integrated cytogenetic study using a combination of comparative genomic hybridization (CGH), spectral karyotyping (SKY) and fluorescence in situ hybridization (FISH) to analyze chromosomal aberrations associated with 8 human esophageal squamous cell carcinoma (EC-SCC) cell lines, and used real-time quantitative PCR (Q-PCR) to study the copy number changes of two candidate genes of chromosome 3q, PIK3CA and TP63, in 20 primary tumors of EC-SCC. The pooled CGH results revealed frequent gain abnormalities on chromosome arms 1p, 1q, 3q, 5p, 6p, 7p, 7q, 8q, 9q, 11q, 12p, 14q, 15q, 16p, 16q, 17q, 18p, 19q, 20q, 22q, and Xq, while frequent losses were found on 3p, 4, 5q, 6q, 7q, 9p, and 18q. SKY detected 195 translocations, 13 deletions and 2 duplications. Among the 374 breakpoints, most clustered at the centromeric regions, such as 8q10, 13q10, 7q10, 9q10, 14q10, 15q10, 16q10, 21q10, and 22q10, but also at other regions, including 3q (3q21, 3q22, 3q25), 7p (7p22, 7p14, 7p12), 7q (7q21, 7q31, 7q32), 8q (8q21.1, 8q23), 11q (11q21, 11q24), 13q (13q14) and 18q (18q21). There was a good correlation between the number of aberrations identified by CGH and SKY (r=0.667; p=0.035). Combined CGH and SKY analyses indicated that chromosomes 3, 7, 9, 11, 14, 16, 18, 19, 20, and 22 harbored higher frequency of chromosomal aberrations than expected. FISH using BAC clones containing oncogene PIK3CA and TP63 found that both genes were amplified in 6 and 5 cell lines, respectively. Q-PCR analysis of primary tumors revealed amplification of PIK3CA and TP63 in 100% and 80% of the cases. Average copy number of PIK3CA per haploid genome was greater than that of TP63 (6.27 vs 2.73), and the difference showed statistical significance (p<0.001). Combination of CGH, SKY and FISH could reveal detailed chromosomal changes associated with esophageal cancer cells, and Q-PCR could assess the change of the candidate genes in clinical samples in a high throughput way. 相似文献
86.
Wang AG Hsu WM Hsia WW Liu JH Yen MY 《Journal of pediatric ophthalmology and strabismus》2001,38(3):166-171
PURPOSE: To investigate the orbital invasion and metastatic pattern in retinoblastoma, and to analyze the correlation with other pathologic and prognostic factors. METHODS: Pathologic and admission records of 45 patients with a pathologically confirmed diagnosis of retinoblastoma during the past 20 years were reviewed. Clinical risk factors and pathologic findings were analyzed for association with tumor invasion/metastasis using chi-square, Fisher's exact, and Student's t tests. RESULTS: Clinical risk factors such as exophthalmos, cataract, and pseudohypopyon were significantly correlated with tumor invasion/metastasis. The pathologic finding of choroid involvement was highly predictive of tumor invasion/metastasis. Delayed enucleation (>3 months) also was significantly correlated with tumor invasion/metastasis. CONCLUSION: Tumor invasion/metastasis is strongly associated with various ocular, pathologic, and treatment outcome factors. Identification of these risk factors may help plan treatment regimens. 相似文献
87.
The fact that vitamin C (ascorbic acid) exhibits a protective effect in certain types of cancer is well documented. Our previous studies demonstrated that human bladder tumor cell line (T24) has N-acetyltransferase (NAT) activity in cytosols and intact cells. The present studies examined the inhibition of arylamine NAT activity and carcinogen (2-aminofluorene)-DNA adduct formation by ellagic acid (EA) in human bladder tumor cell lines (T24 and TSGH 8301). Two assay systems were performed, one with cellular cytosols (9,000 g supernatant), the other with intact bladder tumor cell suspensions. NAT activity and 2-aminofluorene-DNA adduct formation in T24 and TSGH 8301 cells was inhibited by EA in a dose-dependent manner in both systems, i.e.. the greater the concentration of EA in the reaction the greater the inhibition of NAT activity (dose- and time-course dependent effects). The data also indicated that EA decreased the apparent Km and Vmax of NAT enzymes from T24 and TSGH 8301 cells in cytosols. NAT activity and 2-aminofluorene-DNA adducts in T24 is higher than in TSGH 8301. This report is the first to demonstrate that EA affects human bladder tumor cell NAT activity. 相似文献
88.
Jainn-Jim Lin Kuang-Lin Lin Huei-Shyong Wang Shao-Hsuan Hsia Chang-Teng Wu 《European journal of paediatric neurology》2008,12(1):32-37
OBJECTIVE: Encephalitis is an acute infection of brain parenchyma characterized clinically by fever, headache, and an altered level of consciousness. There may also be focal or multifocal neurologic deficits, and focal or generalized seizure activity. Here we report an analysis of status epilepticus (SE) related presumed encephalitis in a series of children. METHODS: We retrospectively reviewed cases of SE related presumed encephalitis treated in the pediatric intensive care unit, between February 2002 and June 2006. Factors evaluated included age, sex, clinical symptoms, seizure type, presence of SE or refractory status epilepticus (RSE), initial electroencephalogram (EEG) finding, neuroimaging study, cerebrospinal fluid (CSF) and outcome. RESULTS: There were 46 patients (19 girls and 27 boys), aged 8 months to 16 years. Twenty (43.4%) of 46 children developed RSE. The major clinical symptoms included fever (100%), upper respiratory symptoms (56.5%) and altered level of consciousness (45.6%). The initial seizure type was categorized as focal (23.9%), generalized (34.8%), primary focal and secondary generalized (41.3%). Initial EEG revealed a focal (30.8%), or multifocal (19.2%) epileptiform discharge in the SE group and a focal (5%), or multifocal (70%) or generalized (25%) epileptiform discharge in the RSE group. The time of follow-up for this study was 6 months to 51 months. In the SE group, 4 died, 16 developed epilepsy and/or neurologic deficits, and 6 returned to baseline. In the RSE group, 6 died, 13 developed epilepsy and/or neurologic deficits, and none returned to baseline. All survivors were discharged on antiepileptic medications. CONCLUSIONS: Our data indicated that children of SE related presumed encephalitis had a high mortality and morbidity. Outcome was related to multifocal or generalized abnormalities of the initial EEG and presence of RSE. 相似文献
89.
Background
Increasing activity levels in adolescents with obesity requires the development of exercise programs that are both attractive to adolescents and easily reproducible. The aim of this study was to develop a modular aerobic training program for adolescents with severe obesity, with a focus on variety, individual targets and acquiring physical skills. We report here the effects on aerobic fitness from a pilot study. Furthermore, we examined the feasibility of the modified shuttle test (MST) as an outcome parameter for aerobic fitness in adolescents with severe obesity. 相似文献90.
复方葆春袋泡茶质量标准研究 总被引:3,自引:0,他引:3
目的:制订复方葆春袋泡茶质量标准。方法:双波长薄层扫描法测定了五味子乙素的量,对淫羊藿,五味子,女贞子进行了薄层色谱鉴别。结果;加样回收率平均为97.15%(RSD=1.2%,n=5),标准曲线r=0.9991,重复性RSD=1.4%(n=6)精密度RSD=2.3%(n=6),结论,方法稳定,可靠,可作为该制剂的质量控制方法之一。 相似文献