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951.
Terribile D  Palumbo F  Nardone L 《Rays》2002,27(4):291-294
Sentinel lymph node biopsy was shown to be an accurate procedure in the study of axillary lymph nodes; it allowed a marked decrease in surgery-related morbidity of breast cancer and axillary dissection could be avoided. Other parameters as molecular markers, nuclear grading, patient age, tumor size, are not able to predict the axillary lymph node status and consequent local therapeutic approach similar to those provided by sentinel lymph node biopsy. The extent of sentinel lymph node metastatic involvement, the extracapsular spread, the size of primary tumor and peritumoral lymphatic/vascular infiltration are the four characteristics shown to be significant, if considered in association and not separately as predictors of the extent of axillary involvement in presence of a positive sentinel lymph node. However, so far, specific studies did not confirm concordant and reproducible results. Therefore, apart from controlled studies, axillary dissection is always required in presence of a metastatic sentinel lymph node.  相似文献   
952.
PURPOSE: We report the case of a male newborn with Ohtahara syndrome and right hemimegalencephaly who presented epileptic negative myoclonus in the first days of life. METHODS: Prolonged polygraphic studies were performed, as well as MRI and a full clinical examination. RESULTS: EEG showed a constant and nonreactive pattern of burst suppression. There were several kinds of electro-clinical seizures (generalized myoclonia, short atonias, typical spasm and tonic spasms) at the beginning of the EEG's burst. The periods of EMG silence, lasting less than 300 ms, were associated with stereotyped EEG transients. CONCLUSIONS: Epileptic negative myoclonus can be observed also in neonatal age. The short transient impairment of motor function observed in the newborn seems linked to the slow component of spike-wave discharge, but its mechanism is still not clear.  相似文献   
953.
954.
It was the aim of this study to compare in vitro closure time (PFA-100), reflecting platelet-related primary hemostasis, to more platelet-specific tests like whole blood electrical aggregometry and platelet surface antigen expression in healthy volunteers. In vitro closure time was measured using a PFA-100. Platelet surface antigen expression (CD63, CD62-P, CD42b, CD36, CD31) was determined in accordance with the consensus protocol for flow-cytometric characterisation of platelet function. Platelet aggregometry was performed using a whole blood electrical aggregometer (ADP and arachidonic acid as agonists). Analysis of the obtained data revealed only a few significant correlations between the different platelet function tests used. This finding can be explained by the various aspects of platelet function being focused by these tests in different extents. Whenever platelet function is analysed, the investigator should be aware of the specific and limited evidence of the method used. For screening purposes, it may be useful to introduce a platelet function index, referring to basal platelet activity, platelet adhesion and platelet aggregation at low and high shear stress forces.  相似文献   
955.
We developed the sliding window correlation procedure in order to examine populations for possible heterogeneity in the ways two variables are related with each other. This procedure involves computing correlation coefficients (R) for overlapping successive segments of the covariate scores. The distribution of resulting Rs reveals fluctuations in the degree and direction of R over the sample of ranked scores. This procedure is applied to behavioral data of aged rats, which were rank-ordered according to water maze performance, and correlated with open field exploration and conflict behavior in a light/dark chamber. Results revealed correlation coefficients of varying magnitudes and opposing directions for different segments of the population, which were obscured by overall correlation analysis. E.g. for the superior learners, the Rs were highest between maze learning ability, increased open field exploration and reduced anxiety in the conflict test, whereas for the intermediate learners the Rs were highest for maze learning ability related with reduced exploration and increased anxiety. Thus, the sliding window correlation distribution can be applied in conjunction with overall correlation analysis to provide information about the potential presence and locations of subgroups within a population, especially if overall correlation analysis does not yield significant results.  相似文献   
956.
A continuing flow of new scientific developments concerning coeliac disease in the last decade asks for the formulation of a new concept of pathophysiology and clinical approach of the coeliac condition. Immunogenetic studies have shown a correlation of the disease to the HLA region on the short arm of chromosome 6. Immunological research has led to the concept of a T-cell driven immunologic response of the small intestine, with the identification of highly sensitive and specific antibodies, and in addition the understanding of the histopathology of coeliac disease has changed dramatically, initiated by the proposition of a spectrum of gluten sensitive enteropathy by Marsh in 1992. Clinical studies report a significant change in patient characteristics and epidemiology. The incidence of the disease has shifted to a majority of adult coeliacs and the disease may present with less severe symptoms of malabsorption while screening studies suggest an overall prevalence of up to 1 in 200-300. In the present paper (an update on histopathology) we specifically describe the work of our group in Arnhem, concerning the identification and validation of the spectrum of intestinal histopathology in gluten sensitive enteropathy, i.e. lymphocytic enteritis (Marsh I lesion), lymphocytic enteritis with crypthyperplasia (Marsh II lesion), and villous atrophy, subdivided in partial villous atrophy (Marsh IIIA), subtotal villous atrophy (Marsh IIIB) and total villous atrophy (Marsh IIIC). Special attention is given to a subgroup of "refractory coeliacs", including the identification of (pre-) malignant aberrant T-cells in the intestinal mucosa of these patients. The new data on immunogenetics, epidemiology, histo-pathology and patient characteristics point to a significant change of views on coeliac disease.  相似文献   
957.
958.
Urticaria has been observed occasionally in association with lymphoproliferative disorders. We report the case of a 56-year-old man with acute urticaria associated with a small cell carcinoma of the lung. Following surgical treatment, the patient remained free of the urticaria.  相似文献   
959.
BACKGROUND: Somatotropic effects are described in the skin. Indeed, acromegaly is in part clinically recognized by cutaneous coarsening. The actual changes in tensile properties associated with the cutaneous manifestations are largely unknown. OBJECTIVES: To study the relationships between the skin tensile properties and the severity of acromegaly as assessed by serum levels of growth hormone (GH) and insulin-like growth factor 1 (IGF-1). PATIENTS AND METHOD: Assessments were made in 13 patients with acromegaly treated by somatostatin agonists combined or not with surgery. A total of 39 age- and sex-matched healthy subjects served as controls. Skin tensile properties were measured on the forearm and nape of the neck using a computerized suction device. RESULTS: Significant differences were yielded between the skin tensile properties in patients and normal subjects. The highest IGF-1 values in the patients' medical records were positively correlated with both skin distensibility and biologic elasticity. The most recent IGF-1 serum levels were negatively correlated with the visco-elastic ratio. No correlations were yielded between any of the biomechanical parameters and GH levels, disease duration and treatment dosages, respectively. CONCLUSION: The skin in acromegaly appears to be functionally more redundant and elastic than normal skin. The biomechanical changes appear quite different from those observed in other diseases with collagen deposition such as diabetes mellitus and scleroderma.  相似文献   
960.
BACKGROUND: Patients with Parkinson disease characteristically exhibit an increased echogenicity of the substantia nigra (SN) on transcranial sonography, a new neuroimaging technique. The same echo feature of the SN can be identified in 9% of healthy adults. OBJECTIVE: To evaluate the relevance of the echogenic SN in healthy adults. DESIGN: In the first part of the study, 10 healthy subjects younger than 40 years with a distinct SN hyperechogenicity underwent extensive neurological, motor, neuropsychological, and fluorine 18-dopa positron emission tomographic ([18F]-dopa PET) examinations. Results were compared with those of 10 subjects with a low echogenic SN. In the second part of the study, the postmortem brains of 20 patients without extrapyramidal disorders during their lifetime were sonographically examined with a particular focus on SN echogenicity. Subsequently, one half of the brain was prepared for heavy metal analysis, the other for a histological examination. RESULTS: Healthy subjects with SN hyperechogenicity exhibited a significant reduction of the [18F]-dopa uptake, especially in the putamen (Wilcoxon matched pair test: left side, P =.006; right side, P =.009), whereas their neuropsychological and motor performance were normal. Postmortem studies showed that the echogenicity of the SN correlated with its iron content. CONCLUSIONS: Increased echogenicity of the SN, characteristically seen in Parkinson disease, is related to a functional impairment of the nigrostriatal system (even in young healthy adults) that can be revealed by [18F]-dopa PET studies. Substantia nigra hyperechogenicity is related to a higher tissue iron level, which is known to enhance the cells' generation of reactive oxygen specimens. Therefore, we hypothesize that transcranial sonography may identify a susceptibility marker for the development of nigral injury that can be detected early in life, prior to the onset of Parkinson disease.  相似文献   
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