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991.
Calprotectin is an abundant neutrophil cytosolic protein released during neutrophil activation or death. The use of plasma calprotectin concentration as a marker of pulmonary inflammation was tested in 31 children with cystic fibrosis, none of whom was acutely unwell or pyrexic. Twenty three were receiving antibiotics, 21 had positive sputum cultures, but none of the traditional tests clearly diagnosed ongoing infection. Plasma calprotectin was significantly higher in the cystic fibrosis group than in matched controls. Sixteen children with cystic fibrosis had values above the control range (320-1570 micrograms/l). Their chest radiograph Northern score, an index of accumulated pulmonary involvement, and their plasma copper, an index of acute phase response, both correlated with plasma calprotectin. Plasma gamma-glutamyltransferase also correlated weakly with plasma calprotectin: thus, hepatic pathology may be a confounding variable. However, the data still suggested that plasma calprotectin is a better index of inflammation than the traditional indices in general use.  相似文献   
992.
A double-blind randomized trial of 50 μg folic acid or placebo given from 2 weeks to 6 months to 130 infants of birthweight less than 2·5 kg has been conducted. While only 62 of the babies completed the 6-month follow-up, no significant difference was found between either group in respect of changes in weight, haemoglobin, serum folate, red cell folate, or evidence of infection. It is concluded that infants in this series were receiving adequate amounts of folic acid in their normal diet and did not require supplements.  相似文献   
993.
Computed tomography was performed on 14 unconscious Kenyan children recovering from cerebral malaria (seven of whom had another scan 12-120 days later) to elucidate the cause of intracranial hypertension and neurological sequelae. Brain swelling, defined as a loss of cerebrospinal fluid spaces, was documented in six children, while a further two had conspicuously small ventricles only. There was severe intracranial hypertension in the two children with definite brain swelling in whom intracranial pressure was monitored. There was no evidence of acute hydrocephalus or vasogenic oedema. Four children with brain swelling also had widespread low density areas suggestive of ischaemic damage. The patterns of damage were not uniform but were consistent with a critical reduction in cerebral perfusion pressure (which was documented in the two in whom this was monitored), hypoglycaemia, or status epilepticus. All four had serious neurological sequelae. These data suggest that brain injury in cerebral malaria may be due in part to secondary systemic and intracranial factors as well as to the direct effect of intravascular sequestration.  相似文献   
994.
In the present study, the vasodilator actions of methanandamide and capsaicin in the rat isolated mesenteric arterial bed and small mesenteric arterial segments were investigated. Methanandamide elicited concentration-dependent relaxations of preconstricted mesenteric arterial beds (pEC(50)=6.0+/-0.1, E(max)=87+/-3%) and arterial segments (pEC(50)=6.4+/-0.1, E(max)=93+/-3%). In arterial beds, in vitro capsaicin pre-treatment blocked vasorelaxation to 1 and 3 microM methanandamide, and reduced to 12+/-7% vasorelaxation to 10 microM methanandamide. Methanandamide failed to relax arterial segments pre-treated in vitro with capsaicin. In arterial beds from rats treated as neonates with capsaicin to cause destruction of primary afferent nerves, methanandamide at 1 and 3 microM did not evoke vasorelaxation, and relaxation at 10 microM methanandamide was reduced to 26+/-4%. Ruthenium red (0.1 microM), an inhibitor of vanilloid responses, attenuated vasorelaxation to methanandamide in arterial beds (pEC(50)=5.6+/-0.1, E(max)=89+/-1%). Ruthenium red at 1 microM abolished the response to 1 microM methanandamide, and greatly attenuated relaxation at 3 and 10 microM methanandamide in arterial beds. In arterial segments, ruthenium red (0.15 microM) blocked vasorelaxation to methanandamide, but not to CGRP. In arterial segments, the vanilloid receptor antagonist capsazepine (1 microM) inhibited, and the calcitonin gene-related peptide (CGRP) receptor antagonist CGRP(8 - 37) (3 microM) abolished, methanandamide-induced relaxations. CGRP(8 - 37), but not capsazepine, attenuated significantly relaxation to exogenous CGRP. These data show that capsaicin and ruthenium red attenuate vasorelaxation to methanandamide in the rat isolated mesenteric arterial bed and small mesenteric arterial segments. In addition, CGRP(8 - 37) and capsazepine antagonize responses to methanandamide in mesenteric arterial segments. In conclusion, vanilloid receptors on capsaicin-sensitive sensory nerves play an important role in the vasorelaxant action of methanandamide in the rat isolated mesenteric arterial bed and small mesenteric arterial segments.  相似文献   
995.
Patients with severe thalassaemia major suffer endocrine and other abnormalities before their eventual death from iron overload due to repeated blood transfusions. The endocrine status of 31 thalassaemic patients aged 2-5 to 23 years was investigated. Exact data were available on the rate and duration of blood transfusion in all of them and in many the liver iron concentration was also known. Although the patients were euthyroid, the mean serum thyroxine level was significantly lower, and the mean thyrotrophic hormone level significantly higher, compared with the values found in normal children. Forty oral glucose tolerance tests with simultaneous insulin levels were performed in 19 children, of whom 5 developed symptomatic diabetes and one had impaired tolerance. Previous tests on all 6 patients were available and some showed raised insulin levels possibly due to insulin resistance. 2 patients had clinical hypoparathyroidism and are described. The parathyroid hormone levels determined by radioimmunoassay in 25 patients were below the mean for the age group in all and outside the reference range in 16. Nonfasting plasma calcium levels were not reduced. Puberty was delayed in some patients. Concentrations of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) measured in urine from 7 girls and 5 boys showed considerable variation. In the boys there was an overall tendency for FSH and LH excretion to be low with regard to age, but with respect to puberty rating FSH exretions were normal or low and LH normal or raised. The girls showed a tendency for LH but not FSH excretion to be raised in relation to puberty rating. The severity of the endocrine changes was related to the degree of iron loading and is discussed in relation to previous work in which the iron loading has rarely been accurately indicated nor parathyroid status assessed.  相似文献   
996.
997.
OBJECTIVE: To compare the efficacy and toxicity of topical vaginal 5-fluorouracil (5-FU) maintenance therapy against the effects of observation after standard treatment for high-grade cervical dysplasia in human immunodeficiency virus (HIV)-infected women and to evaluate the association between baseline CD4 count and time to recurrence. METHODS: In a phase III unmasked, randomized, multicenter, outpatient clinical trial, 101 HIV-positive women either received 6 months of biweekly treatment with vaginal 5-FU cream (2 g) or underwent 6 months of observation after standard excisional or ablative cervical treatment for cervical intraepithelial neoplasia (CIN). Papanicolaou smears and colposcopy were scheduled at regular intervals during the ensuing 18 months, with the primary end point being the time at which CIN of any grade recurred. RESULTS: Thirty-eight percent of women developed recurrence: 14 (28%) of 50 in the 5-FU therapy group and 24 (47%) of 51 in the observation group. Treatment with 5-FU was significantly associated with prolonged time to CIN development (P = .04). Observation subjects were more likely to have high-grade recurrences, with 31% developing CIN 2-3 compared with 8% in the 5-FU treatment arm (P = .014), and disease recurred more quickly in observation subjects as well. Baseline CD4 count was related significantly to time to recurrence (P = .04), with 46% of subjects with CD4 counts less than 200 cells/mm3 developing recurrence compared with 33% of subjects with CD4 counts at least 200 cells/mm3. Disease recurred more slowly in subjects who had received antiretroviral therapy than in antiretroviral therapy-naive subjects. There were no instances of grade 3 or 4 toxicity, and compliance with 5-FU treatment was generally good. CONCLUSION: Adjunctive maintenance intravaginal 5-FU therapy after standard surgery for high-grade lesions safely and effectively reduced recurrence of cervical intraepithelial neoplasia in HIV-infected women.  相似文献   
998.
Identifying outstanding clinical nurses: the 'star' shines in oncology   总被引:1,自引:0,他引:1  
Abstract There are some oncology nurses who are special. They are ‘good’ nurses but they are more, somehow they ‘shine’. They are ‘stars’. Many nurses will identify the same nurse as a ‘star’ but what makes a nurse a ‘star’? Twelve semistructured interviews were conducted in which oncology nurses were asked to describe an oncology nurse who stood out in terms of clinical practice. The ‘star’ nurse was easily and readily recalled and described by participants. Analysis revealed 21 grouped themes relating to the ‘star’ nurse. Each theme was allocated to one of four headings: ‘Nurses’ ways of Being; Doing; Knowing; and Giving and Receiving’ ( Stiles, 1990 ). The ‘star’ nurse is professional, committed and caring; delivers excellent nursing care both basic and technical; is knowledgeable; has advanced communication skills, and establishes strong relationships with clients and peers. From this, it is clear that caring and psycho-social aspects of care are only part of the make up of the ‘star’ nurse, and that the complexity of the ‘star’ nurse has not been highlighted in the literature.  相似文献   
999.
1000.
Type 2 diabetes is characterised by insulin resistance and progressive beta-cell dysfunction (which leads to hyperglycaemia), the risk of progressive worsening of glycaemic control and an increased risk of both macrovascular and microvascular complications. Existing treatment strategies target deficient insulin secretion and insulin resistance, but do not generally address the underlying progressive beta-cell dysfunction that is common to Type 2 diabetes. Traditionally, Type 2 diabetes is first treated with medical nutrition therapy (reduced food intake and increased physical activity), followed by stepwise addition of oral antidiabetes therapies and, ultimately, exogenous insulin, as required. Unfortunately, these approaches have not been shown to delay the need for additional therapies, nor do they generally prevent or delay the inexorable decline in beta-cell function. Patients with Type 2 diabetes commonly experience deterioration in glycaemic control, and may have substantial weight gain due to the diabetes therapies that contribute to worsening obesity. In addition, insulin-providing therapies, such as sulfonylureas and exogenous insulin, carry the risk of hypoglycaemia, and cannot fully address the complex hormonal irregularities that characterise Type 2 diabetes, including the role of glucagon hypersecretion. New therapeutic approaches are being developed that couple durable glycaemic control with improved control of body weight. These approaches include development of the incretin mimetics, which are a novel class of agents that share several of the glucoregulatory effects of incretin hormones, such as glucagon-like hormone-1. Deficiency of glucagon-like hormone-1 secretion is known to be present in those with abnormal glucose tolerance. Agents that manipulate the physiological actions of incretin hormones, such as glucagon-like hormone-1, may significantly benefit patients with Type 2 diabetes.  相似文献   
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