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In the forest zone of Cameroon, small-scale family farmers practicing traditional slash and burn practices achieve a clear field by piled burning of the branches and trunks of cleared vegetation. Plant growth inhibition on ash patches, and the risk of nutrient loss from these areas, was evaluated on field plots on which 0.5 t m–2 or 1.0 t m–2 of wood was piled and burnt, and in laboratory studies. The ash produced by burning was strongly alkaline, and laboratory bio-assessment studies showed that the saline, high pH conditions produced in ash patches prevented germination and plant growth for up to two wet seasons, as is observed in the field. Field and laboratory studies demonstrated rapid release (1 wet season) of K and S from the ash and the loss of a substantial portion of these nutrients from the soil profile by leaching. In contrast, leaching carries Mg from the ash gradually (3 to 4 wet seasons), while Ca, Cu, Zn and P are leached slowly. The nutrients contained in ash patches are considered at risk of loss both through leaching (K and S) and by erosion of ash (Ca, Mg, Cu, Zn and P). Farmers should be encouraged to spread ash patches prior to cultivation in order to exploit the nutrient content of ash and to lessen the risk of nutrient loss.  相似文献   
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OBJECTIVE: The aim of the study was to determine the pattern of health care utilization of people aged 55-74 years with arthritic pain in the knee or hip. DESIGN: People with current pain were identified in a population-based study. A filter model was used to describe the pattern of health care utilization of people who presented as patients at different levels (GPs or specialist) of the health care system in the Netherlands. SETTING: The study was carried out in the district of Ommoord in Rotterdam in an age- and gender-representative sample of 831 (response 83%; n = 691) people. STUDY PARTICIPANTS: A group of 186 people with current pain was identified. They completed a questionnaire and were interviewed. MAIN OUTCOME MEASURES: Background variables, illness-related variables (including radiological osteoarthritis), and self-reported diagnoses were described and compared for attenders and non-attenders of GPs and specialists. A reference group of patients of GPs was used to determine the validity and generalizability of the findings. RESULTS: Eighty-two per cent consulted a GP (passed filter 1). In 69% of the GP attenders, 'arthritis' was identified (passed filter 2), and 65% of them attended a specialist (passed filter 3). People who did not pass the various filters were different from those who did with respect to the body mass index (lower; OR 1.24), the chronicity of pain (less chronic pain; OR 4.9) and attendance of a physiotherapist (lower; OR 5.6). The chronicity of pain seems of more importance in determining the health care utilization pattern than the severity of pain, the level of disability or the presence of radiological osteoarthritis. We suggest that health promotion interventions could increase the self-management ability of patients and could lower costs.  相似文献   
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Spermine decreased distinctly the activity of Ca2+ -phospholipid-dependent protein kinases, whereas not affected the protein kinase A activity. Content of cytosol estradiol receptors was drastically decreased in rat uterine in presence of the polyamine. The data obtained and literature data suggest that activation of estradiol receptors appears to occur after phosphorylation by means of Ca2+ - dependent protein kinases, which are regulated via phosphoinositide-involving mechanism, i.e. these receptors acquire the ability to bind hormones.  相似文献   
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If genetic testing for breast and ovarian cancer predisposition is to become available within a public health care system there needs to be a rational and cost-effective approach to mutation analysis. We have screened for BRCA1 mutations in 230 women with breast cancer, all from the Wessex region of southern England, in order to establish the parameters on which to base a cost-effective regional mutation analysis strategy. Truncating mutations were detected in 10/155 (6.5%) consecutive cases selected only for diagnosis under the age of 40 (nine of these ten women had a strong family history of breast or ovarian cancer), 3/61 (4.9%) bilateral-breast cancer cases (all three mutations occurring among women for whom the first cancer was diagnosed under 40 years) and 8/30 (26.6%) breast cancer cases presenting to the genetics clinic (for whom a strong family history of breast and/or ovarian cancer was present). Ten different mutations were detected in 17 families, but three of these accounted for 10/17 (59%) of the families. The cost of screening the population for mutations in the entire BRCA1 gene is unacceptably high. However, the cost of screening a carefully selected patient cohort is low, the risk of misinterpretation much less and the potential clinical benefits clearer.  相似文献   
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Testicular germ cell tumour is said to be a model for curable neoplasm. However, the prognosis of primary extragonadal germ cell tumour does not appear to be as promising. Though similar in histology, the biology of primary extragonadal germ cell tumour is different as exemplified by the patients in this review. Eight patients with primary mediastinal germ cell tumours were treated with intensive cisplatin-based chemotherapy. All, except one, had non-seminomatous components. The poor prognosis of mediastinal germ cell tumour is due to a combination of poor treatment results with the cisplatin-based regimen and the development of non-germ cell and haematological malignancies.  相似文献   
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In the department of microsurgery of A.A. Vishnevsky Central Hospital the transplantation and transposition of the at the gunshot injuries of the extremities have begun to execute since 1990. For this time 94 surgical interventions have been conducted at 88 wounded: 57 transplantations and 37 transpositions of the bloody tissues. The transplantation and transposition of the vascularized complexes of tissues with application of microsurgical technique is the effective method of the treatment of the wounded in the extremities. In the conditions of the local armed conflicts it is necessary to provide deployment of the department of microsurgery at stages of the specialized medical care.  相似文献   
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