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Twenty-five euthyroid patients who underwent cardiac surgery with fentanyl-oxygen anesthesia were studied. The authors confirm that some thyroid hormones undoubtedly take part in a non-specific pool of reactions caused by surgical stress. For one or more days, all the patients had total triiodothyronine (TT3) and free triiodothyronine (FT3) levels clearly below the normal values, with a parallel increase in reverse triiodothyronine (rT3, biologically inactive). Changes in total (TT4) and free thyroxine (FT4), although significant, were smaller and hard to interpret. The most important changes occurred on the first postoperative day. Of seven patients who before the operation had a TT3 value below the lower normal limit, six had at discharge a mean TT3 level significantly above it. Serum TT3 concentrations could be a reliable prognostic index. High-dose fentanyl anesthesia probably does not affect thyroid hormone response to surgical stress. To date, the mechanisms which cause reduction of serum triiodothyronine have not been fully discovered and it is not known for certain whether this reduction is beneficial to the human organism.  相似文献   
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We describe a patient with acute B-lymphocyte lymphoblastic leukemia who developed laboratory changes (not detectable free thyroxine, TSH 66 microIU/ml) suggesting severe primary hypothyroidism. Histological examination at autopsy showed massive leukemic infiltration of the thyroid gland: the progressive reduction of thyroid hormone levels with concomitant increase in TSH levels observed over a three-month period from the onset of the hemopathy suggests a cause-effect relationship between leukemic infiltration of the thyroid gland and hypothyroidism.  相似文献   
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Clericuzio-type poikiloderma with neutropenia is a well-defined nosological entity, but despite a remarkable number of clinical reports, no long term follow-up data has been presented to date regarding patients with this rare condition.Here we describe the results of clinical follow-up of three siblings, one male (Patient 1) and two females (Patients 2 and 3), subsequent to their first clinical and then molecular diagnosis of Clericuzio-type poikiloderma with neutropenia syndrome due to mutation of USB1gene. Patient 1 always expressed the most severe phenotype, while patients 2 and 3 showed an intermediate and mild phenotype, respectively, as observed since their first clinical evaluation. None of the patients developed skin cancer and/or myelodysplastic disorders considering the peripheral haematological findings. Lens opacity, never reported before, was found in two of the three patients.The long term follow-up observations confirm the stability over time of the pronounced intra-familial heterogeneity of clinical manifestations observed prior to and upon molecular diagnosis. We conclude that prolonged follow-up is an adjunct tool to monitor intra-familial variability of PN clinical spectrum which may favour surveillance of more serious complications of the disease among siblings, when a patient-specific clinical expressivity is present.  相似文献   
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The surface-spreading synaptonemal complex (SC) technique was employed to analyze spermatocytes and oocytes of rainbow trout in order to visualize the process of autosome and sex chromosome synapsis in this species. The structure of lateral elements (LEs) of the SC and the chromosome synapsis process at the stages of leptotene, zygotene and pachytene are described. Comparative analysis of SCs of spermatocytes and oocytes showed a difference in the synaptic process, i.e. in spermatocytes all LEs were synapsed before the appearance of centromeric regions in the biarmed elements, while in the oocytes some fully synapsed LEs, including the centromeric region of the biarmed elements, were found together with fully or partially unsynapsed LEs. In males the sex chromosome synapsis starts only after all autosomes have synapsed. Irregular synapses involving three or four LEs were found in 3.4% of the cells analyzed in mid or late zygotene. Multivalents were found in males and females. Some aspects of initial meiotic development and their implications in rainbow trout cytogenetics, genetics and evolution are discussed.  相似文献   
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LCx was compared to other assays in measuring human immunodeficiency virus type 1 (HIV-1) CRF02 viremia. LCx showed significant but low correlation with the other methods. Values of <2.60 log(10) cp/ml were observed in 29.6% of specimens with LCx and in only 14.8% with bDNA and PCR, suggesting suboptimal performance of LCx with CRF02.  相似文献   
8.
Peripheral blood lymphocytes from a total of 111 patients and 40 healthy individuals were studied for gamma interferon (IFN-gamma) expression on their surfaces by indirect immunofluorescence assay and flow cytometry, with a new anti-IFN-gamma monoclonal antibody (IGMB-14) as a specific reagent. Of 64 patients with proven acute viral infections, 59 had a significantly higher percentage of lymphocytes expressing IFN-gamma on their membranes than healthy individuals did. On the other hand, only 3 (8.9%) of 34 patients with proven bacterial infections had an increased percentage of IFN-gamma-expressing lymphocytes. None of the eight patients with other infections and none of the five with systemic lupus erythematosus showed an increased percentage of IFN-gamma-positive lymphocytes. The percentage of IFN-gamma-expressing lymphocytes during a viral infection was found to be related to different stages of the disease. Finally, some applications of this rapid IFN-gamma assay method in viral diseases are discussed.  相似文献   
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Spermatogenesis of 'corvina' P. squamosissimus starts from a stem cell that gives rise to germ cells. These cells are enveloped by Sertoli cells, forming cysts. The germ cells in the cysts are all at the same stage of development and are interconnected by cytoplasmic bridges. Spermatogonia are the largest germ cells. In the cysts, these cells differentiate into primary spermatogonia and secondary spermatogonia. The primary spermatogonia are isolated in the cyst and give rise to the secondary spermatogonia. After several mitotic divisions, they produce spermatocytes I, which can be identified by synaptonemal complexes in the nucleus. The spermatocytes I enter the first phase of meiosis to produce the spermatocytes II. These are not very frequently seen because they rapidly undergo a second phase of meiosis to produce spermatids.  相似文献   
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