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61.
Hypothyroidism developed in a neonate following the excision of a large cervical teratoma. This finding supports the observation that cervical teratomas commonly arise from thyroid tissue. Thyroid function tests should be performed routinely in all patients in whom identifiable residual thyroid tissue is not demonstrated at the conclusion of the operation. Accepted: 19 December 1997  相似文献   
62.
Persistent hyperinsulinemic hypoglycaemia of infancy (PHHI) is the most frequent cause of hypoglycaemia in infancy. Clinical presentation is heterogeneous, with variable onset of hypoglycaemia and response to diazoxide, and presence of sporadic or familial forms. Underlying histopathological lesions can be focal or diffuse. Focal lesions are characterised by focal hyperplasia of pancreatic islet-like cells, whereas diffuse lesions implicate the whole pancreas. The distinction between the two forms is important because surgical treatment and genetic counselling are radically different. Focal lesions correspond to somatic defects which are totally cured by limited pancreatic resection, whereas diffuse lesions require a subtotal pancreatectomy exposing to high risk of diabetes mellitus. Diffuse lesions are due to functional abnormalities involving several genes and different transmission forms. Recessively inherited PHHI have been attributed to homozygote mutations for the beta-cell sulfonylurea receptor (SUR1) or the inward-rectifying potassium-channel (Kir6.2) genes. Dominantly inherited PHHI can implicate the glucokinase gene, particularly when PHHI is associated with diabetes, the glutamate dehydrogenase gene when hyperammonaemia is associated, or another locus.  相似文献   
63.
OBJECTIVE: To estimate the prevalence of Huntington disease (HD) in New South Wales on Australian Census Day (6 August) 1996. DESIGN: Survey of records of the Huntington Disease Service and major hospitals, and of neurologists, psychiatrists, clinical geneticists and genetic counsellors. SUBJECTS AND SETTING: All patients in NSW who, on Census Day 1996, either had a definite diagnosis of HD (motor signs of chorea or ataxia and family history of HD or positive DNA test result) or would have had signs and later received a definite diagnosis (assessed 1 April 1997 to 1 July 1999). MAIN OUTCOME MEASURES: Prevalence (HD patients per 100,000 population); patient characteristics; year and basis of diagnosis. RESULTS: 380 patients with definite HD were identified, giving a prevalence of HD in NSW in 1996 of 6.29 per 100,000 population (95% CI, 5.68-6.96). A third of HD patients were aged 60 years or older. Diagnosis was confirmed by DNA testing for 171 patients (45%), including 30 (8%) with no recorded family history. Average numbers of new diagnoses per year were 11.8 (1984-1988), 21.8 (1989-1993) and 28.6 (1994-1998). Estimated number of people with a 50% risk of inheriting the HD mutation was 25.2 per 100,000 population. Estimated incidence of HD in 1996 was 0.65 per 100,000 population. CONCLUSIONS: Prevalence of HD in NSW is similar to estimated prevalence in other Australian and Western populations. Increasing numbers of cases are being diagnosed, and the 18 chronic care beds currently designated for HD patients in NSW are unlikely to be sufficient.  相似文献   
64.
PURPOSE: Long-term brain metastases survivors are at risk for neurologic morbidity after whole-brain radiotherapy (WBRT). Retrospective radiosurgery (RS) reports found no survival difference when compared with WBRT. Before RS alone was evaluated with delayed WBRT in a phase III trial, the feasibility of RS alone was tested prospectively. PATIENTS AND METHODS: Patients with renal cell carcinoma, melanoma, or sarcoma; one to three brain metastases; and performance status of 0 to 2 were enrolled. Exclusion criteria were leptomeningeal disease; metastases in medulla, pons, or midbrain; or liver metastases. On the basis of tumor size, patients received 24, 18, or 15 Gy RS. At recurrence, management was discretionary. The primary end point was 3- and 6-month intracranial progression. RESULTS: Between July 1998 and August 2003, 36 patients were accrued; 31 were eligible. Median follow-up was 32.7 months and the median survival was 8.3 months (95% CI, 7.4 to 12.2). Three- and 6-month intracranial failure with RS alone was 25.8% and 48.3%. Failure within and outside the RS volume, when in-field and distant intracranial failures were scored independently, was 19.3% and 16.2% (3 months) and 32.2% and 32.2% (6 months), respectively. Approximately 38% of patients experienced death attributable to neurologic cause. There were three grade 3 toxicities related to RS. CONCLUSION: Intracranial failure rates without WBRT were 25.8% and 48.3% at 3 and 6 months, respectively. Delaying WBRT may be appropriate for some subgroups of patients with radioresistant tumors, but routine avoidance of WBRT should be approached judiciously.  相似文献   
65.
The aims were to determine the median survival and prognostic factors of patients with central nervous system (CNS) metastases managed with whole‐brain radiation therapy (WBRT), and to explore selection criteria in recently published clinical trials using aggressive interventions in CNS metastases. A retrospective audit was performed on patients managed with WBRT for CNS metastases. Potential prognostic factors were recorded and analysed for their association with survival duration. The proportion of patients with these factors was also compared with those of patients managed under three recently reported studies investigating aggressive interventions, such as radiosurgery and chemotherapy for CNS metastases. Seventy‐three patients were treated with WBRT for cerebral metastases over a 12‐month period. The median survival of the population was 3.4 months (95% confidence interval: 2.7–4.1), with 6‐ and 12‐month survival rates of 30 and 18%, respectively. Significant prognostic factors for prolonged median survival were Eastern Cooperative Oncology Group status 0–2 (P = 0.015), Medical Research Council neurological functional status 0–1 (P = 0.006), and Recursive Partitioning Analysis Class 2 versus Class 3 (P = 0.020). On multivariate analysis, younger patient age (P = 0.02) and better performance status (P < 0.01) were associated with improved outcome. When comparing these characteristics with selected published studies, our study cohort demonstrated a higher proportion of patients with poor performance status, a greater number of metastases per patient and a higher incidence of extracranial disease. This reflects the selected nature of patients in these published studies. Central nervous system metastases confer a poor prognosis and, for the majority of patients, aggressive interventions are unlikely to improve survival. The use of potentially toxic and expensive treatments should be reserved for those few in whom these studies have shown a potential benefit.  相似文献   
66.
The nicotine-derived tobacco-specific nitrosamine, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), is one of the most potent and abundant procarcinogens found in tobacco and tobacco smoke and is considered to be a causative agent for several tobacco-related cancers. Glucuronidation of the major metabolite of NNK, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), has been implicated as an important mechanism for NNK detoxification. To characterize NNAL metabolism by N-glucuronidation in humans, high-pressure liquid chromatography was used to detect glucuronide conjugates of NNAL formed in human liver microsomes in vitro. In addition to peaks corresponding to the O-glucuronides of NNAL (NNAL-O-Gluc), a second series of peaks were observed in human liver microsomes that were identified by liquid chromatography-mass spectrometry to be NNAL N-glucuronides (NNAL-N-Gluc). Microsomes prepared from liver specimens from individual subjects (n = 42) exhibited substantial variability in the levels of NNAL-N-Gluc (49-fold variability) and NNAL-O-Gluc (49-fold variability) formed in vitro. This variability was likely not due to differences in tissue quality, as substantial variability (5-fold) was also observed in the ratio of NNAL-N-Gluc/NNAL-O-Gluc formation, with a mean ratio of 1.7 in the 42 specimens. Liver microsomes from smokers (n = 14) exhibited no significant difference in the levels of either NNAL-N-Gluc or NNAL-O-Gluc formation, or in the ratio of NNAL-N-Gluc/NNAL-O-Gluc formation, as compared with liver microsomes from never smokers (n = 28). Overexpressed UDP-glucuronosyltransferase (UGT) 1A4 exhibited significant levels of N-glucuronidating activity (V(max)/K(m) = 3.11 microl. min(-1). g(-1)) in vitro; no NNAL-N-glucuronide formation was detected for the 11 other overexpressed UGT enzymes tested in these studies. These results demonstrate the importance of N-glucuronidation in the metabolism of NNAL and the role of UGT1A4 in this pathway.  相似文献   
67.
Post partum thyroiditis occurs in 50% of TPO AB+ve women and is characterised by transient hyperthyroidism followed by transient hypothyroidism during the first six months, post partum. A third of the latter group develop permanent hypothyroidism. The syndrome is seen in 5-9% of women and post partum thyroid dysfunction (PPTD) reoccurs in 75% of women in a subsequent pregnancy. An increase in depressive symptomatology is seen in women with PPTD as well as in ante TPO Ab+ve women without PPTD. The immunology of PPT is associated with the presence of TPO antiboides with those IgG subclasses best able to activate the complement cascade. The HLA-DR frequencies seen in PPT suggest that PPT may be related to Hashimoto's thyroiditis. TPO Ab driven complement fixation is seen in PPT and complement activation relates to the extent and progression of thyroid damage. Recent studies have shown an increase in both Th2 and Th1 cytokine release from lymphocytes in ante partum women destined to develop PPTD. More data are required on the cellular immune changes both ante partum and post partum in PPT.  相似文献   
68.
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70.
There has been significant progress towards the goal of eliminating vertical transmission of HIV by 2015. However, a question that remains is how we can most effectively prevent late postnatal transmission of HIV through infant feeding. Guidelines published by the World Health Organization in 2010 have been widely adopted. These guidelines place strong emphasis on exclusive breastfeeding, in some countries over‐turning a prior emphasis on formula feeding. Where available, provision of antiretroviral treatment for HIV‐positive mothers or prophylaxis for infants offers additional protection against vertical transmission through infant feeding. However, merely changing guidelines is not sufficient to change practice, particularly with regard to culturally sanctioned forms of feeding, such as mixed feeding. This commentary highlights structural, social and contextual barriers to effective implementation of the guidelines and suggests ways to address some of these barriers.  相似文献   
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