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41.
An unusual case of malignant melanoma metastatic to the lung and to the ovaries occurred 9 and 11 years, respectively, after the initial, extragenital diagnosis. The primary lesion invaded to Clark's level IV with a thickness of greater than 4 mm, normally grave prognostic indicators. A metastatic lung nodule seen radiographically remained unchanged for two years before discovery of the intraperitoneal disease. The case illustrates the clinical variability and unpredictable biologic behavior of malignant melanoma.  相似文献   
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BACKGROUND: To adequately address the complex health needs of young people, their access to services, and the quality of services received, must be improved. AIMS: To explore the barriers to service provision for young people and to identify the training needs of primary healthcare service providers in New South Wales (NSW), Australia. DESIGN OF STUDY: A cross-sectional, qualitative study of the perspectives of a range of health service providers. SETTING: A range of primary healthcare organisations across NSW. METHODS: Samples of general practitioners (GPs), youth health workers, youth health coordinators, and community health centre staff were drawn from urban and rural clusters across NSW. Focus groups and interviews were used to identify barriers to service provision and the training needs of service providers. Data were tape recorded, transcribed, and analysed. RESULTS: Barriers to service provision among GPs and community health centre staff included inadequate time, flexibility, skills, and confidence in working with young people, and poor linkages with other relevant services. Training needs included better knowledge of and skills in adolescent health requirements, working with adolescents, and working with other services. Barriers to service provision for youth health workers and coordinators included lack of financial resources and infrastructure. There were few linkages between groups of service providers. CONCLUSION: Models of service provision that allow stronger linkages between service providers, sufficient time for consultation with young people, adequate training and support of health professionals, and flexibility of service provision, including outreach, should be explored and evaluated.  相似文献   
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The States of Mind (SOM) model provided a framework for assessing the balance between self-reported positive and negative affects in a sample of 39 outpatients with major depression and 43 healthy control subjects. The SOM model proposes that healthy functioning is characterized by an optimal balance of positive (P) and negative (N) cognitions or affects (P/(P + N) approximately 0.63), and that psychopathology is marked by deviations from the optimal balance. Research thus far has focused on the functional significance of cognitive rather than affective balance. Within this framework, we hypothesized that patients in untreated episodes of major depression would balance their positive and negative affects at the same level where depressed patients in other studies have balanced their positive and negative cognitions--namely, at P/(P + N) approximately 0.37. Points and confidence interval (CI) estimation procedures yielded results (mean = 0.35, 95% CI = 0.30 - 0.40) consistent with this hypothesis in a sample of 39 depressed male outpatients. Correlational analysis indicated that affect balance is inversely related to symptom severity as measured by self-report (Beck) and clinician-rating (Hamilton) scales.  相似文献   
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A case of unilateral haematocolpos correctly diagnosed by ultrasound is described in a 13 year old girl known to have a solitary kidney. The association of renal agenesis with Müllerian abnormalities is well recognised and in this case the ultrasound findings ensured that the correct surgical management was undertaken.  相似文献   
47.
The major afferent pathways to the visual cortex were studied in cats enucleated at postnatal days 0, 15, 30 and 60 using the retrograde tracer wheat germ agglutin conjugated horseradish peroxidase (WGA-HRP). Following enucleation at days 0 and 15, the lateral gyrus was shrunken and cortical thickness was decreased, but the thickness of layer I was increased relative to normal adult cats. The laminar portion of the lateral geniculate complex occupied only half its normal volume, but the pathway from the intralaminar nuclei to visual cortex was doubled in volume. The ipsilateral and contralateral claustrum and ipsilateral medial septal nucleus also provided increased input to visual cortex. The changes in these projection patterns were not as dramatic in the cats enucleated at days 30 and 60. The callosal pathway between areas 17 and 18 was also significantly altered in cats enucleated on the day of birth and at day 15. Callosal cells were found in the infragranular layers throughout area 18. The number of supragranular callosal cells in the medial half of area 18 and in area 17 was reduced to approximately one third the normal adult number, but the mediolateral extent of this zone was not reduced. In the infragranular layers, the callosal cell number was approximately twice that in adult cats, and they occupied at least twice their normal mediolateral extent. Following bilateral enucleation at days 30 and 60, the cell numbers and mediolateral extent of the callosal cell zones approximated those in normal adult cats. Taken together, these results indicate that early deafferantiation of a cortical area can alter the thalamic, extrathalamic and callosal connections of that area.  相似文献   
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Purpose. The objective of this study was to determine the relationship between muscular strength and bone mineral density (BMD) in patients undergoing regular haemodialysis. Methods. The BMD was measured in the lumbar spine (L2L4) and in the proximal femur (femoral neck and trochanter) with dual-energy X-ray absorptiometry (DEXA (Lunar DPX). Muscular strength of the extensors, flexors and abductors muscles of the femur (proximal muscles) and extensors muscles of the back was measured with an isometric cynamometer. Thirty patients, 15 women with a mean age of 33.7 years (18-43) and 15 men with a mean age of 15.5 years (18-65) were included in the study. Results. There was a positive and significant correlation between the BMD of the femoral neck and muscular strength of the flexors (r=0.490, P<0.005), the extensors (r=0.658, P<0.01) and the abductors muscles of the femur (r=0.671, P <0.0008), as well as between the muscular strength of the flexors (r=0.413, P <0.02) and extensors muscles of the femur (r=0.433, P <0.01) with BMD of the trochanter. There was no correlation between the muscular strength of the back extensor muscles and the BMD of the lumbar spine (r=-0.119, P NS). There was no correlation between the BMD and the number of years of haemodialysis therapy (r=-0.032, P NS), the patient's age (r=-159, P NS), or the value of serum PTH (r=0.369, P NS) respectively. However, there was a significant correlation between the BMD of the femoral neck with muscular strength (r=0.602, P <0.05). Conclusion. This study reveals the close relationship that exists between muscular strength of the proximal muscles and the BMD of proximal femur in patients undergoing haemodialysis.  相似文献   
50.
Background: The murine analogue of X-linked hypophosphateaemia is the Hyp mouse; it has chronic phosphate depletion from an inherited defect of renal tubular reabsorption. Phosphate directly regulates the parathyroid (PT) in normal rats and it is of interest whether this regulation is intact in Hyp mice. Methods: Hyp mice were fed either a low-phosphate diet or control diet and PTH mRNA levels were measured. In addition changes in NMR-visible kidney and muscle intracellular phosphate potentials in normal and Hyp mice were determined. Mice were maintained on a low-phosphate (0.02%) or normal-phosphate (0.6%) diet for 24 and 72 h. Results: On the normal diet, Hyp mice had hypophosphataemia, normocalcaemia, and normal PTH mRNA levels. Phosphate deprivation for 72 h led to a profound fall in plasma phosphate, a slight but significant rise in plasma calcium, and a dramatic decrease in PTH mRNA, similar to that of normal mice fed this diet. Changes in kidney and muscle intracellular phosphate measured by NMR spectroscopy were not affected by diet or genotype. Conclusion: Dietary phosphate deprivation decreased Hyp mice PTH mRNA levels and caused no change in intracellular phosphate potentials. Therefore Hyp mice parathyroids' adapt appropriately to phosphate deprivation albeit at a lower threshold compared to normal mice.  相似文献   
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