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31.
32.
H J Decker B Wullich J M Whaley G Herrera S M Klauck A A Sandberg D W Yandell B R Seizinger 《Cancer Genetics and Cytogenetics》1992,63(1):25-31
In a previously studied family with inherited renal cell carcinoma (RCC), RCC was shown to segregate with a constitutional balanced t(3;8)(p14.2;q24.1). In addition, we recently showed that in a RCC tumor from this family the constitutional translocation became unbalanced, suggesting a genetic mechanism that may be associated with the primary genetic events of tumorigenesis. We now report that the RCC tumor cells from this case showed additional cytogenetic alterations, possibly related to tumor progression, which include an additional tumor-specific translocation involving band 14 of chromosome 13. Because this band contains the retinoblastoma (RB) gene, we examined the tumor for aberrations in the RB gene using DNA sequence polymorphism analysis and pulsed-field gel electrophoresis (PFGE), but did not detect alterations in the RB gene. 相似文献
33.
Measurements of the turnover of dopamine, noradrenaline and serotonin and their metabolites have been performed in the superior colliculus of adult and aged rats. The turnover of dopamine, noradrenaline and their metabolites after pargyline treatment was significantly lower in aged rats than in adults. On the contrary, the synthesis rate of serotonin (measured by accumulation of 5-hydroxytryptophan after decarboxylase blockade) and the turnover rate of serotonin (after pargyline treatment) did not change during aging. These findings suggest that aging has a different effect on catecholamines and serotonin turnover in the superior colliculus of the aged rats. 相似文献
34.
Cytology is a powerful diagnostic tool but to make definitive diagnoses, the use of ancillary techniques is imperative. By combining immunohistochemistry (IHC) and electron microscopy (EM), cytologic diagnoses can be as precise as those of surgical pathology. In the authors' daily practice of cytopathology they use all ancillary techniques available to them: histochemistry, IHC, EM, flow cytometry, and molecular pathology. IHC is frequently used as an ancillary technique in their daily practice but EM is many times their technique of choice. By the use of EM the authors can make specific final diagnoses, make the diagnosis more definitive, narrow the differential diagnosis, or determine the origin of a neoplasm with unknown primary site. Specimens obtained by fine-needle aspiration as well as all body fluids are suitable for EM. The limiting factor is to obtain the appropriate material with the diagnostic cells for ultrastructural examination. The common diagnostic dilemmas in the everyday practice of cytology are the following: mesothelioma vs. adenocarcinoma, neuroendocrine differentiation or not, the distinction of melanoma from adenocarcinoma and sarcoma, hepatocellular carcinoma vs. adenocarcinoma, and the origin of adenocarcinomas of unknown primary. The authors discuss how they approach these diagnostic problems in their everyday practice and how they incorporate EM in solving them. 相似文献
35.
36.
Guerkov RE Targoni OS Kreher CR Boehm BO Herrera MT Tary-Lehmann M Lehmann PV Schwander SK 《Journal of immunological methods》2003,279(1-2):111-121
Single-cell resolution cytokine ELISPOT assays are increasingly used to gain insights into clonal sizes of type 1 and type 2 effector T cell populations in vivo. However, ELISPOT assays permitting monitoring of regulatory IL-10-producing T cells have so far not been established. Unlike IFN-gamma, IL-2, IL-4, and IL-5 assays performed on PBMC in which the recall antigen-induced cytokine spots are T cell-derived, we show here that in such assays IL-10 is primarily monocyte-derived. T cell-derived IL-10 spots were 80 x 10(3) microm(2) in size, seven times larger than spots produced by monocytes, and B cells produced even smaller spots. Based on spot size gating and the use of B cells as APC, we have established test conditions that permit measurement of cognate IL-10 production by low-frequency antigen-specific T cells. IL-10-producing PPD-specific CD4(+) T cells were detected in frequencies comparable to IFN-gamma-secreting CD4(+) T cells in tuberculosis patients, but not in uninfected healthy control individuals. In contrast, IL-10-secreting CD4(+) T cells specific for a panel of recall antigens could not be detected in frequencies >1/100,000 in healthy individuals whose CD4(+) cells responded to these antigens with type 1 or type 2 cytokine production in the 1:100,000-1:1000 frequency range. Therefore, the induction of IL-10-producing T cells seems to be under tighter control than that of Th1/Th2 cells, apparently confined to states of chronic immune stimulation. Access to low-frequency immune monitoring of IL-10-producing T cells will provide new insights into the role of regulatory T cells in health and disease. 相似文献
37.
Herrera MF Velázquez D Bezauri P Angeles-Angeles A Uscanga LF Robles-Díaz G 《Gaceta médica de México》2003,139(1):21-25
Computarized tomography allows proper identification and evaluation of stage in the majority patients with periampullary tumors. However, 30% of peritoneal metastases cannot be seen in image studies. The aim of the present study was to evaluate the role of laparoscopy with laparoscopic ultrasound in the staging process of pancreatic and ampullary tumor. Diagnostic laparoscopy was performed on 20 patients included in the study Mean age was 58.35 +/- 13.4 years. Twelve were males and eight females. In two patients, laparoscopy showed peritoneal metastases and ultrasound did not show extrapancreatic involvement. In five patients, there was vascular invasion without metastases. In three patients, both peritoneal metastases and vascular invasion were found, and in five there was neither vascular invasion nor metastasis. Laparoscopic findings were confirmed in a but one patient. In 14 of the 16 patients In whom peritoneal lavage was performed, microscopic exam showed a sufficient number of cells to make a diagnosis. We concluded that laparoscopy with ultrasound is useful in staging of patients with duodeno-bilio-pancreatic malignancies. 相似文献
38.
María Gutiérrez Fernández David Carrasco de Andrés Luis Miguel Salmerón Febres Lucas González Herrera Silvia Jiménez Brobeil 《Cirugía espa?ola》2021,99(1):55-61
IntroductionTo analyse the influence of socioeconomic status on the clinical profile of patients undergoing non-traumatic lower-limb amputation.MethodsRetrospective study of 697 lower-limb amputee patients in an Angiology and Vascular Surgery Department during a 5-year period. Patients were classified according to their socioeconomic status (low, medium and high). We analysed demographic (age and gender) and clinical variables (cause of amputation, comorbidity, cardiovascular risk factors and amputation level).ResultsMean age was 70.5 ± 11.9 years, and the median was 72 years. The low socioeconomic status group presented a higher frequency of amputations in men. Cardiovascular risks factors were more frequent in this socioeconomic group, and the difference was statistically significant for diabetes (85.8% low, 69.3% medium, 65% high; P<.01) and obesity (31.4% low, 22.6% medium, 12.5% high, P<.01). Diabetic retinopathy was the only comorbidity with a significant association with low socioeconomic status (21.1% low, 15.3% medium, 12.5% high, P<.03). Regarding the cause for amputation, there was no difference in terms of socioeconomic status. The low socioeconomic level showed a higher frequency of major amputation, which was a significant difference (63.6% low, 41.2% medium, 55% high, P<.04) and a higher predisposition for this amputation level.ConclusionsThe low socioeconomic status has been shown to determine an unfavourable vascular risk profile in lower-limb non-traumatic amputees and a higher predisposition of a major amputation. This socioeconomic level demonstrates a negative influence on these patients’ diabetes, obesity and diabetic retinopathy. 相似文献
39.
Summary Several different fluorescent mitochondrial dyes were tested as vital stains for motor nerve terminals and other cells in frog skeletal muscles. It was found that 3,3diethyloxadicarbocyanine iodide and 4-(4-diethylaminostyryl)-N-methylpyridinium iodide were most useful. Both dyes labelled motor nerve terminals with high reliability. Electrophysiological and morphological control experiments showed that these dyes could be used to repeatedly observe neuromuscular junctions in living animals without affecting synaptic growth or remodelling. The importance of appropriate controls was emphasized by the finding that illumination, if excessively intense or prolonged, can cause physiological and structural damage to nerve terminals. Additional observations indicated that these dyes may be useful for determining the mitochondrial content, and therefore oxidative capacity, of living muscle fibres. It was also found that the fluorescent dyes labelled cells identified as muscle satellite cells, and that these myoblast precursors could be visualized in fixed whole mounts with a nitroblue tetrazolium stain. Both methods were used to study reactive cells that were closely associated with muscle fibres in lesioned muscles. Mitochondrial dyes also labelled the microvasculature, associated axons and other cells. 相似文献
40.
F Prats M Porta Serra H Yazbeck R Herrera J M Gassó 《Gaceta sanitaria / S.E.S.P.A.S》1990,4(20):179-183
OBJECTIVES: To estimate the prevalence of antibodies to human immunodeficiency virus (HIV), antibodies to hepatitis B core antigen (anti-HBc), hepatitis B surface antigen (HBsAg), and antibodies to delta virus (anti-DV). DESIGN: Cross-sectional (prevalence) study. A non-proportional (stratified by length of stay) random sample of 20% of admitted patients was selected. CLINICAL SETTING: The Hospital Psiquiátrico Nuestra Se?ora de Montserrat (Sant Boi de Llobregat, Barcelona, Spain) admits about 670 patients in its short-term, rehabilitation (mid-term) and long-term wards. SUBJECTS: 139 patients were selected: 91% were males, mean age was 55 years, and 10% belonged to an HIV risk group; mean length of hospitalization since last discharge was 13 years. MEASUREMENTS: Blood samples were drawn in October, 1988. Anti-HBc, HBsAg and anti-DV were determined by competitive enzyme immunoassay (EIA). Anti-HIV-1 were determined by sandwich EIA; negativity of results with high absorbency but below the cut-off point was confirmed by Western blot. RESULTS: None of the sampled patients had circulating anti-HIV-1 antibodies. Four cases showing high absorbency (below the "cut-off" point) were ruled out by Western-blot. Overall, the prevalence of anti-HBc was 52.8% (54.4% in long-term wards, 35.0% in mid-term wards, and 13.8% in short-term wards). The prevalence of HBsAg was 2.3%, of anti-DV 1.5%, and of HDAg 0%. CONCLUSIONS: Prevalence of anti-HIV is null in the studied institution. Current efforts to prevent HIV infection must continue; a hepatitis B vaccination program is highly warranted among patients and professionals of the studied hospital. 相似文献