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11.
AIM: To investigate the effects of early dexamethasone administration on activation of circulating neutrophils and monocytes in preterm infants with respiratory distress syndrome requiring treatment with surfactant. METHODS: Neonates (n = 30) with respiratory distress were randomized to receive dexamethasone (DEX group, 29.1 +/- 1.2 wk, 1223 +/- 156 g, n = 15) from the first postnatal day, or to serve as controls (control group, 29.2 +/- 1.4 wk, 1250 +/- 148 g, n = 15). Dexamethasone was given as a 4 d course (0.5 mg kg(-1) on postnatal days 1 and 2, and 0.25 mg kg(-1) on days 3 and 4). Polymorphonuclear leucocyte (PMN) and monocyte surface expression of CD11b, L-selectin and CD14 was quantified with flow cytometry, and plasma macrophage-inflammatory protein-1alpha (MIP-1alpha) with an enzyme-linked immunosorbent assay. Blood samples were collected on days 1, 2-3 and 5-7. RESULTS: In the DEX group 1/15, and in the control group 7/15 developed bronchopulmonary dysplasia (p < 0.04). PMN CD11b (median 100, range 70-190 vs 154, 96-213, p=0.01), monocyte CD14 (235, 102-433 vs 355, 219-533, p=0.01) and plasma MIP-1alpha (20 ng l(-1), 20-32 vs 37 ng l(-1), 20-70, p = 0.005) were lower in the DEX group at days 2-3. All adhesion molecule expression and plasma MIP-1alpha levels were comparable at days 5-7, with the exception of monocyte L-selectin expression levels, which remained lower in the DEX group. CONCLUSION: In preterm infants with respiratory distress syndrome, early dexamethasone causes downregulation of PMN and monocyte activation. This may attenuate pulmonary inflammation and improve pulmonary outcome.  相似文献   
12.
A novel putative tumor suppressor gene, pHyde, was recently cloned from rat prostate. The rat gene has been shown to inhibit prostate cancer cell proliferation both in vitro and in vivo. However, the role of human pHyde in prostate cancer has not been studied before. Here, we analyzed human prostate cancer cell lines (LNCaP, DU145, PC-3, 22Rv1), xenografts (LuCaP 23.1, 35, 41, 49, 58, 69, 70 and 73) and clinical prostate carcinomas for genetic alterations and expression of pHyde. The expression of pHyde in normal human tissues as well as in prostate cancer was studied by Northern analysis and real-time quantitative RT-PCR. It was ubiquitously expressed in all normal tissues analyzed. Although, the expression was significantly (p=0.007) lower in poorly differentiated than in well and moderately differentiated carcinomas, there were no differences in the expression levels between benign prostate hyperplasia, untreated primary and recurrent hormone-refractory prostate carcinomas (p=0.607). Altogether, missense mutations were detected in 2 out of 68 samples studied ( approximately 3%) by denaturing high-performance liquid chromatography (DHPLC) and sequencing. One of the samples with the mutation also exhibited a loss of a gene copy by fluorescence in situ hybridization (FISH). This was the only sample that exhibited a genetic alteration in both alleles, suggesting that the human pHyde is not a classical prostate tumor suppressor gene. The reduced expression of the gene found in some tumors warrant further studies.  相似文献   
13.
目的:探讨寻找干细胞移植治疗急性心肌梗死的最佳移植治疗时间,指导临床应用,提高临床疗效。方法:应用计算机检索medline2000-01/2006-05文章,检索词为:"stem cell transplantation and/or acute myocardialinfarction(AMI)and/or chronic heart failure or ischemic cardiomyopathy",限定文章语言种类为English;同时计算机检索中国期刊全文数据库,相同时间的文章,检索词:"干细胞移植治疗,干细胞移植与急性心肌梗死,干细胞移植治疗与心力衰竭或慢性缺血性心肌病",限定文章语言种类为中文。共检索到300余篇与主题有关的文献,其中12篇有价值的文章见参考文献。移植时间取平均值,并按射血分数值和P值进行列表、作图。对干细胞移植时间与射血分数值之间的关系进行分析。结果:在急性心肌梗死后2~5d和9d以后进行干细胞移植治疗疗效较24h内及6~8d为好。结论:干细胞移植治疗急性心肌梗死的移植时间与临床疗效之间可能存在一定的相关性。经冠脉注入干细胞比经静脉或经心内膜下注入可以更好地改善左室功能,但还需要进一步的临床资料证实。  相似文献   
14.
Background:  Permanent teeth pulp exposures have traditionally been treated with calcium hydroxide pulp capping. The aim of this study was to investigate the response of human pulp tissue which were mechanically exposed to a new material, Propolis and compare it with two existing and commonly used pulp capping agents (mineral trioxide aggregate and Dycal).
Methods:  Thirty-six intact human premolars were mechanically exposed. Teeth were divided into six groups of 6 teeth each and were capped with Propolis, mineral trioxide aggregate and Dycal. Final restoration was done with posterior composite resin using light cured glass ionomer cement as a liner. The teeth were then extracted on the 15th or the 45th day and processed for histological evaluation.
Results:  Differences in inflammatory response and dentine bridge formation of the exposed pulp to the three different materials were statistically calculated using chi-square test and were found to be non-significant. There was more pulp inflammation in teeth treated with Dycal than with Propolis and MTA on the 15th as well as on the 45th day. Propolis and MTA showed bridge formation in more teeth, and the bridges were in closer proximity to pulp capping material than teeth treated with Dycal on the 45th day.
Conclusions:  The response of pulps to Propolis as a pulp capping agent was comparable to MTA and Dycal.  相似文献   
15.
Purpose: To assess whether a young man with multiple disabilities and minimal motor behaviour would learn to control environmental stimulation using chin movements and a mechanical microswitch. Method: The study was carried out according to an ABAB design in which A represented baseline and B intervention phases. The chin movements controlled the stimulation only during the intervention phases. A 2-month post-intervention check was conducted. Results: The man increased the frequency of his chin movements, thus increasing the level of environmental stimulation, during the intervention phases. This performance was maintained at the post-intervention check. Conclusion: The use of chin movements is a practical strategy for enabling individuals with minimal motor movements to control environmental stimulation. Future research should examine whether similar types of movements may enable some individuals to control voice-output communication devices.  相似文献   
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17.
Purpose: To assess the effectiveness of a computer system used as a microswitch for word utterances of two adults with multiple disabilities. The system combined a new control software programme with a commercially available speech recognition programme. Method: Nine word utterances were targeted for each participant. The participant's emission of those utterances triggered the occurrence of related (favourite) stimuli during the intervention and the post-intervention check. Results: Intervention data showed that (1) the participants increased the frequencies of the target utterances and (2) the computer system recognized about 80% of those utterances correctly, providing the participants with high levels of favourite stimulation. The post-intervention check showed comparable data with both participants. Conclusions: The computer system proved an adequate microswitch for word utterances. Based on this evidence, microswitch programmes could be extended beyond the use of conventional motor responses.  相似文献   
18.
OBJECTIVES: The basic phases of constructing compact questionnaire scales for health-promotion interventions are demonstrated in the case of attitudes towards two modes of physical activity, outdoor aerobic exercise (OAE) and everyday commuting activity (ECA). The scales were to show good psychometric properties and to provide adequate indicators of attitude. METHODS: Behaviours and criteria were specified for both OAE and ECA. The items describing the emotional (affect) and cognitive (outcome-expectations) aspects of attitude towards OAE and ECA behaviours were selected on the basis of a pilot study. The scales under development were used in a Finnish population survey on health, personal resources and physical activity (n = 1,516). Item analyses were completed for purposes of refining the scale; principal component analyses and factor analyses were used to establish the dimensional structure of the scales. Evidence of discriminatory validity was provided by comparing the scale scores of the different groups of respondents with regular, with sub-criterion, and without any OAE and ECA behaviours, respectively. RESULTS: The purported psychometric properties were met in the case of the affective and, less obviously, the positive outcome-expectation scales. The negative expectation scales need to be reconstructed with additional items. CONCLUSIONS: The psychometric properties of the affective scales and the positive expectation scales allow conclusions to be drawn regarding group differences in attitudes towards OAE or ECA behaviours. These scales are ready to be cross-validated in a new sample. Test-retest reliability should also be established.  相似文献   
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20.
Bogdanova NV, Antonenkova NN, Rogov YI, Karstens JH, Hillemanns P, Dörk T. High frequency and allele‐specific differences of BRCA1 founder mutations in breast cancer and ovarian cancer patients from Belarus. Breast cancer and ovarian cancer are common malignancies in Belarus accounting for about 3500 and 800 new cases per year, respectively. For breast cancer, the rates and age of onset appear to vary significantly in regions differentially affected by the Chernobyl accident. We assessed the frequency and distribution of three BRCA1 founder mutations 5382insC, 4153delA and Cys61Gly in two hospital‐based series of 1945 unselected breast cancer patients and of 201 unselected ovarian cancer patients from Belarus as well as in 1019 healthy control females from the same population. Any of these mutations were identified in 4.4% of the breast cancer patients, 26.4% of the ovarian cancer patients and 0.5% of the controls. In the breast cancer patients, BRCA1 mutations were strongly associated with earlier age at diagnosis, with oestrogen receptor (ER) negative tumours and with a first‐degree family history of breast cancer, although only 35% of the identified BRCA1 mutation carriers had such a family history. There were no marked differences in the regional distribution of BRCA1 mutations, so that the significant differences in age at diagnosis and family history of breast cancer patients from areas afflicted by the Chernobyl accident could not be explained by BRCA1. We next observed a higher impact and a shifted mutational spectrum of BRCA1 in the series of Byelorussian ovarian cancer patients where the three founder mutations accounted for 26.4% (53/201). While the Cys61Gly mutation appeared underrepresented in ovarian cancer as compared with breast cancer cases from the same population (p = 0.01), the 4153delA mutation made a higher contribution to ovarian cancer than to breast cancer (p < 0.01). BRCA1 mutations were significantly enriched among ovarian cancer cases with a first‐degree family history of breast or ovarian cancer, whereas the median age at ovarian cancer diagnosis was not different between mutation carriers and non‐carriers. Taken together, these results identify three BRCA1 founder mutations as key components of inherited breast and ovarian cancer susceptibility in Belarus and might have implications for cancer prevention, treatment and genetic counselling in this population.  相似文献   
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