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51.
Objective : To describe the obstetric and perinatal factors, in particular the method of delivery, associated with development of a subgaleal haematoma (SGH) and to determine the outcome of survivors with this type of birth trauma. Methodology : Perinatal and obstetric data were retrospectively reviewed for 37 infants admitted to the neonatal unit of the sole tertiary paediatric referral hospital in Western Australia with an SGH, over a 24 year period from 1970 to 1993. These data were compared to data for all Western Australian births. The long-term outcome was obtained through medical and private paediatric records for 26 of these infants. Results : All except one of the neonates had instrumental deliveries; 89% had a vacuum extractor applied to the head at some stage of delivery compared to 10% of the general population of births in Western Australia. There was also a significantly increased risk of failure of attempted vacuum extraction. Of the cases where a vacuum extraction was attempted, 45% also had forceps applied to the head. Coagulopathy was associated with the severity of the SGH. There was also a high frequency of occurrence (40%) of associated head trauma such as intracranial haemorrhage, skull fracture and cerebral oedema, as well as neonatal encephalopathy (73%). The occurrence of these associated features did not correlate significantly with the severity of SGH. Minor complications of SGH included jaundice and facial bruising. There was an excess mortality associated with SGH; however, the long-term outcome for neonatal survivors with this disorder was good. None of the cases studied subsequently developed cerebral palsy or intellectual disability, and minor neurological sequelae only were documented in four infants. Conclusions : SGH is an uncommon type of birth trauma, and is associated with delivery or attempted delivery by vacuum extraction. The most commonly associated clinical problems were hypovolaemia and coagulopathy. The long-term outcome for neonates with this condition is good. 相似文献
52.
Ajona D Castaño Z Garayoa M Zudaire E Pajares MJ Martinez A Cuttitta F Montuenga LM Pio R 《Cancer research》2004,64(17):6310-6318
The complement system is important in immunosurveillance against tumors. However, malignant cells are usually resistant to complement-mediated lysis. In this study, we examine the expression of factor H, an inhibitor of complement activation, and factor H-like protein 1 (FHL-1), its alternatively spliced form, in lung cancer. We also evaluate the potential effect of factor H/FHL-1 in the protection of lung cancer cells against the activation of the complement cascade. By Northern blot analysis we demonstrate a high expression of factor H and FHL-1 in most non-small cell lung cancer cell lines, although neuroendocrine pulmonary tumors (small cell lung carcinoma and carcinoid cell lines) had undetectable levels. Western blot analysis of conditioned medium showed the active secretion of factor H and FHL-1 by cells that were positive by Northern blot. Expression of factor H/FHL-1 mRNA was also shown in a series of non-small cell lung cancer biopsies by in situ hybridization. Interestingly, many cultured lung cancer cells were able to bind fluorescence-labeled factor H to their surfaces. Deposition of C3 fragments from normal human serum on H1264, a lung adenocarcinoma cell line, was more efficient when factor H/FHL-1 activity was blocked by specific antibodies. Blocking factor H/FHL-1 activity also enhanced the release of anaphylatoxin C5a and moderately increased the susceptibility of these cells to complement-mediated cytotoxicity. In summary, we demonstrate the expression of factor H and FHL-1 by some lung cancer cells and analyze the contribution of these proteins to the protection against complement activation. 相似文献
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Understanding diet and energy balance as risk factors for breast, colon,
and other cancers requires information on the contribution of each factor
and of interactions among factors to cancer risk. Rodent models for breast
cancer provide extensive data on effects of dietary fat and calories,
energy balance, body weight gain, and physical activity on tumor
development. Analyses of the combined data from many studies have shown
clearly that quality and quantity of dietary fat and energy balance
contribute independently to increased mammary gland tumorigenesis. These
findings were seen in female rats fed diets high in fat (35-40% of
calories) compared to rats fed control diets, with approximately 10% of
calories as fat (Fay and Freedman, 1997, Breast Cancer Res. Treat. 46,
215-223). The methods used permit comparison of experimental and
epidemiological data, and they may be useful in extrapolating between
species and developing public health recommendations. In addition to the
contributions of lifetime-diet composition, intake, energy balance, and
physical activity to cancer risk, there are questions about the timing and
duration of alterations in these factors and about the "dose-response"
characteristics of cancer risk to the factors. Endocrine mechanisms may be
significant in mammary gland tumor risk, but experimental and
epidemiological data indicate that cancers at other sites, such as colon
and liver, also are influenced by the factors listed. Other diet and
lifestyle factors that influence energy, or specifically fat, metabolism
may also affect risk for cancers that are promoted by increased intake of
fat and calories. Studies of separate and interactive effects of dietary
fat, black tea, weight gain, and mammary gland tumorigenesis (Rogers, et
al, 1998, Carcinogenesis 19, 1269-1273) have been analyzed. Using
adjustment of carcinogenesis endpoints for body weight, tumor burden, and
latency, they were found to be related to weight gain within treatment
groups in 2 of 3 experiments.
相似文献
55.
Background
Postal questionnaires are an economical and simple method of data collection for research purposes but are subject to non-response bias. Several studies have explored the effect of monetary and non-monetary incentives on response. Recent meta-analyses conclude that financial incentives are an effective way of increasing response rates. However, large surveys rarely have the resources to reward individual participants. Three previous papers report on the effectiveness of lottery incentives with contradictory results. This study aimed to determine the effect of including a lottery-style incentive on response rates to a postal health survey.Methods
Randomised controlled trial. Setting: North and West Birmingham. 8,645 patients aged 18 or over randomly selected from registers of eight general practices (family physician practices). Intervention: Inclusion of a flyer and letter with a health questionnaire informing patients that returned questionnaires would be entered into a lottery-style draw for £100 of gift vouchers. Control: Health questionnaire accompanied only by standard letter of explanation. Main outcome measures: Response rate and completion rate to questionnaire.Results
5,209 individuals responded with identical rates in both groups (62.1%). Practice, patient age, sex and Townsend score (a postcode based deprivation measure) were identified as predictive of response, with higher response related to older age, being female and living in an area with a lower Townsend score (less deprived).Conclusion
This RCT, using a large community based sample, found that the offer of entry into a lottery style draw for £100 of High Street vouchers has no effect on response rates to a postal health questionnaire. 相似文献56.
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