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Alberto Barros M. Carmo Tavares Sérgio Castedo M. Salomé Pereira M. Purificação Tavares M. Almeida e Costa 《Human genetics》1987,75(4):388-390
Summary A double balanced reciprocal translocation involving four chromosomes, t(1;19;6;14) (1p11; 19p11; 6q25; 14q21), was found in the phenotypically normal husband in a couple referred because of repeated abortions. Reciprocal translocations, t(6;14), had been transmitted by his mother, his father being apparently homozygous for a translocation comprising pairs 1 and 19-t(1;19)(1;19). The genetic consequences of this complex chromosomal rearrangement are analyzed. 相似文献
24.
The erythrocyte-mediated reduction of selenite has been reproduced by the addition of reduced glutathione to plasma at levels comparable to those present in the erythrocyte. The reaction has been followed by chromatography and ultraviolet (UV) absorption spectroscopy (in the absence of plasma). The first detectable compound, selenium diglutathione, is very unstable in physiological conditions. The product of the reaction does not contain glutathione and is able to react and incorporate selenium into plasma proteins without the participation of hemoglobin or glutathione reductase. A saturable low molecular weight compound is also able to bind selenium, which may be relevant in the initial distribution and excretion of selenium after selenite administration. 相似文献
25.
Shifts in Methanogenic Subpopulations Measured with Antibody Probes in a Fixed-Bed Loop Anaerobic Bioreactor Treating Sulfite Evaporator Condensate 总被引:3,自引:3,他引:0 下载免费PDF全文
Alberto J. L. Macario Everly Conway de Macario Ulrich Ney Siegfried M. Schoberth Hermann Sahm 《Applied microbiology》1989,55(8):1996-2001
A fixed-bed loop, high-rate anaerobic bioreactor treating sulfite evaporator condensate was sampled when it reached steady state and afterwards following perturbations during a 14-month period. By using immunotechnology, it was observed that shifts in methanogenic subpopulations occurred in association with perturbations, such as restarting and relocating the biomass into a different tank. Methanogens related to Methanobacterium bryantii MoHG and Methanobrevibacter smithii ALI were numerous throughout the observation period, while Methanosarcina mazei S6 and Methanosarcina thermophila TM1 were found in the early and late samples, respectively. Also, Methanobacterium formicicum was more numerous at the top portion of the bioreactor, while Methanobrevibacter arboriphilus AZ and DC were at the bottom. Sample formalinization required for prolonged storage proved suitable for antigen preservation. 相似文献
26.
Armando Menendez-Pelaez Alberto Martinez-Telleria Jose A. Vega Carmen Coalla Russel J. Reiter 《The Histochemical journal》1989,21(3):125-130
Summary Monoamine oxidase (MAO) and alcohol dehydrogenase (AD) activities were studied histochemically in the Syrian hamster Harderian gland using tryptamine as substrate and Nitroblue Tetrazolium as the final electron acceptor. No dark: light-related changes were observed. Male type I secretory cells showed an intense MAO reaction. Female type I cells exhibited a moderate MAO activity. Both male and female glands showed a moderate/intense AD-positive reaction. Male type II cells were lacking MAO and AD activities. MAO activity found in the hamster Harderian glands corresponded mainly to MAO type A since treatment with chlorgyline (0.01, 0.1 and 0.5mm) totally inhibited it. The possible role of these two enzymes in Harderian gland indolalkylamine metabolism is discussed. 相似文献
27.
A Piovesan M Panarelli M Terzolo G Osella C Matrella P Paccotti A Angeli 《Chronobiology international》1990,7(3):263-265
We monitored the circadian profiles of cortisol, systolic and diastolic blood pressure (SBP and DBP) and heart rate (HR) in 33 matched normotensive subjects, 32 patients with essential hypertension and 16 patients with Cushing's Syndrome (8 pituitary adenomas, 6 adrenal adenomas and 2 adrenal carcinomas). Each subject underwent serial blood drawings at 4-hr intervals along the 24-hr cycle. BP and HR were automatically recorded every 30 min. Data were analyzed by conventional statistics and by chronobiological procedures (cosinor rhythmometry). Both the control subjects and essential hypertensives showed a circadian profile of BP and HR characterized by a peak in the early afternoon and a clear nocturnal fall (rhythm detection: P less than 0.001). The rhythmicity of BP was disrupted in patients affected by Cushing's Syndrome, whereas the 24-hr oscillation of HR was preserved (P less than 0.001). Our data are compatible with the view that glucocorticoids are involved in the control of BP circadian rhythm, whereas HR is not under their control. 相似文献
28.
L. Dogliotti A. Berruti T. Buniva M. Torta A. Bottini M. Tampellini M. Terzolo R. Faggiuolo A. Angeli 《The Journal of steroid biochemistry and molecular biology》1990,37(6):983-987
A number of studies performed in vitro and on experimental animals supported the view that pineal gland inhibits neoplastic growth. Data in humans are scanty and controversial. In the present study we measured serum melatonin (MT), prolactin (PRL) and growth hormone (GH) concentrations, at 08.00 and 24.00, in 132 cancer patients and in 58 healthy control subjects. The patients were stratified according to histology and stage of disease as follows: 30 stage I–II and 45 stage III–IV breast cancer (BC); 39 stage III–IV lung cancer; 18 advanced gastrointestinal (GI) cancer. We also measured MT levels, at the same time-points, in 20 women with primary BC before and after radical mastectomy. Finally, we evaluated the circadian rhythm of serum MT in 18 patients with advanced cancer. On the whole, the patients with advanced tumors showed serum MT levels significantly higher than controls, without any correlation with PRL and GH values. When looking at stage III–IV vs stage I–II BC patients, significantly higher MT levels have been found in the former group. The surgical removal of the primary BC was not associated with any changes in MT values at both time points considered. A highly significant rhythm of serum MT was recorded in advanced cancer patients and the rhythmic parameters were substantially superimposable on those of the control subjects. 相似文献
29.
Dr. Concepción Calvo Ana García de la Paz Victoria Bejar Emilia Quesada Alberto Ramos-Cormenzana 《Current microbiology》1988,17(1):49-53
Thirty-eight strains ofDeleya halophila species were examined for production of phage after mitomycin C induction. Thirty-two of them were able to inhibit growth of some other strains. Phage F9-11, isolated fromD. halophila strain F9-11, showed an isometric head and a noncontractile tail. The effects of salt concentrations variation on the stability and replication of this phage were established. Its replication was possible at a wide range of marine salt concentrations, from 2.5% to 15% (wt/vol). Stability seems to be influenced by osmolarity of medium rather than by NaCl level. The euryhaline character showed by F9-11 phage is evoked as an important factor for the survival of this phage in its environment. 相似文献
30.
Maria Di Bello Valeria Lucchini Stefania Chiari Roberto Colleoni Nicoletta Colombo Alberto Mantovani Paola Allavena 《Cancer immunology, immunotherapy : CII》1988,27(1):63-68
Summary Expression of HLA-DR antigens by purified preparations of human ovarian carcinoma cells freshly isolated from surgical specimens was examined in parallel with the capacity of tumor cells to elicit a blastogenic response from autologous lymphocytes in mixed lymphocyte-tumor culture (MLTC) assay. Of 21 tumor preparations, 11 (52%) reacted with monoclonal antibodies 279 and/or 949 specific for a monomorphic determinant of HLA-DR antigens, with heterogeneous positivity, ranging between 30% and 95%. In this series of patients positive MLTC occurred in 8/21 individual experiments. The HLA-DR expression was proportionally similar in tumors giving positive MLTC (4/8=50%) and negative MLTC (7/13=53%). The lack of correlation between DR expression on tumor cells and stimulatory activity in autologous MLTC and the fact that DR-negative tumors could induce lymphocyte stimulation, support the hypothesis that blastogenesis occurs upon recognition of tumor-associated antigens, different from DR molecules, possibly tumor-specific antigens. 相似文献