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71.
Claudio Oliveira Fausto Foresti Marcos Guilherme Rigolino Yara Aiko Tabata 《Chromosome research》1995,3(3):182-190
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
72.
Laura A Hawryluck William RC Harvey Louise Lemieux-Charles Peter A Singer 《BMC medical ethics》2002,3(1):3-9
Background
Intensivists must provide enough analgesia and sedation to ensure dying patients receive good palliative care. However, if it is perceived that too much is given, they risk prosecution for committing euthanasia. The goal of this study is to develop consensus guidelines on analgesia and sedation in dying intensive care unit patients that help distinguish palliative care from euthanasia.Methods
Using the Delphi technique, panelists rated levels of agreement with statements describing how analgesics and sedatives should be given to dying ICU patients and how palliative care should be distinguished from euthanasia. Participants were drawn from 3 panels: 1) Canadian Academic Adult Intensive Care Fellowship program directors and Intensive Care division chiefs (N = 9); 2) Deputy chief provincial coroners (N = 5); 3) Validation panel of Intensivists attending the Canadian Critical Care Trials Group meeting (N = 12).Results
After three Delphi rounds, consensus was achieved on 16 statements encompassing the role of palliative care in the intensive care unit, the management of pain and suffering, current areas of controversy, and ways of improving palliative care in the ICU.Conclusion
Consensus guidelines were developed to guide the administration of analgesics and sedatives to dying ICU patients and to help distinguish palliative care from euthanasia. 相似文献73.
74.
D B Oliveira 《Journal of immunological methods》1986,91(1):99-105
By taking advantage of the cross-reaction for human F liver protein (F antigen) of a monoclonal antibody raised to mouse F antigen, human F antigen has been immunopurified in bulk. The molecular weight is 44 000. Using this material as a standard, affinity-purified polyclonal anti-F antibody on a solid phase and radiolabelled monoclonal anti-F antibody to detect bound protein, a capture immunoradiometric assay capable of detecting down to 1 ng X ml-1 of F antigen has been developed. Using this assay, the average level of F antigen in normal mouse serum (CBA strain) is 16 ng X ml-1 (360 pM) and in human serum 10 ng X ml-1 (250 pM). 相似文献
75.
Rocha AM Rocha GA Santos A de Oliveira CA Queiroz DM 《Journal of clinical microbiology》2003,41(1):447-448
We validated a commercial enzyme-linked immunosorbent assay for the detection of anti-CagA antibodies in Brazilian patients with Helicobacter pylori infection. The test presented high sensitivity (97.4%) and specificity (88.9%) when employed in patients without gastric carcinoma. However, in gastric carcinoma patients, the test was neither sensitive nor specific enough to detect cagA-positive H. pylori infection. 相似文献
76.
Neves NA Carvalho LP De Oliveira MA Giraldo PC Bacellar O Cruz AA Carvalho EM 《Clinical and experimental immunology》2005,142(1):167-171
To determine whether there is an association between atopy and recurrent vaginal candidiasis (RVC) and to evaluate the type-2 immune response in patients with RVC. Evaluation of immediate hypersensitivity skin tests to aeroallergens, measurement of total IgE and Candida albicans specific IgE and levels of IL-5 in 44 women with RVC and 26 with sporadic vaginal candidiasis (SVC). Statistical analyses were performed by Mann-Whitney test and chi(2) test with Yates correction. History of atopy (68%) and positive skin test (42%) were higher (P < 0.05) in RVC than in patients with SVC. No significant difference was found in total IgE, C. albicans specific IgE and IL-5 levels. There was a strong association between atopy and RVC, but type-2 immune response to C. albicans antigen was absent or similar in the two groups of patients. 相似文献
77.
Pinheiro PS Rodrigues RJ Silva AP Cunha RA Oliveira CR Malva JO 《Neuroscience letters》2003,336(2):97-100
Alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors have been identified mostly as postsynaptic receptors mediating fast glutamatergic synaptic transmission. However, neurochemical studies based on the modulation of neurotransmitter release have suggested the existence of presynaptic AMPA receptors. We have used a recently described technique that allows a high-purity fractionation of the pre- and postsynaptic proteins of synaptic junctions to evaluate the distribution of the different AMPA receptor subunits in rat hippocampal synapses. Surprisingly, we found very high levels of GluR1- and GluR2/3-like immunoreactivity in the presynaptic fraction, but also in the postsynaptic and extrasynaptic fractions. GluR4-like immunoreactivity was much less abundant but was still detected, predominantly in the postsynaptic fraction. This methodology appears to be far more sensitive than the classical immunogold electron microscopy to determine the localization of synaptic receptors. 相似文献
78.
RC Curran 《Journal of clinical pathology》1983,36(2):239-240
79.
80.
Andreo JC Oliveira JA Navarro JA Roque DD Roque JS Buchain RL 《Okajimas folia anatomica Japonica》2002,79(1):33-41
Samples of the anterior and posterior regions of the masseter and temporal muscles and of the anterior belly of the digastric muscle of 4 adult male tufted capuchin monkeys (Cebus apella) were removed and stained with HE and submitted to the m-ATPase reaction (with alkaline and acid preincubation) and to the NADH-TR and SDH reactions. The results of the histoenzymologic reactions were similar, except for acid reversal which did not occur in fibers of the fast glycolytic (FG) type in the mandibular locomotor muscles. FG fibers had a larger area and were more frequent in all regions studied. No significant differences in frequency or area of each fiber type were detected, considering the anterior and posterior regions of the masseter and temporal muscles. The frequency of fibers of the fast oxidative glycolytic (FOG) and slow oxidative (SO) types and of FOG area differed significantly between the anterior belly of the digastric muscle and the mandibular locomotor muscle. The predominance of fast twitch (FG and FOG) fibers and the multipenniform and bipenniform internal architecture of the masseter and temporal muscles, respectively, are characteristics that permit the powerful bite typical of tufted capuchin monkeys. 相似文献