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81.
82.
After filling root canals, the healing process depends on the chemical composition or physical-chemical properties of the material used, among other factors. All root canal sealers, whether solid or plastic, are foreign matter for the body if they remain in permanent contact with apical and periapical tissues. As a result, the first organic reaction that occurs is an attempt to phagocytize the material. During phagocytosis, macrophages release a large number of cell mediators into the area, among which are cytokines that are essential in intercellular communication and in many physiological and pathophysiological processes. One of these cytokines is tumor necrosis factor-alpha (TNF-alpha), which acts through links to specific receptors on the cell membrane initiating a cascade of events leading to induction, activation, or inhibition of numerous cytokine-regulated genes in the cell nucleus. The release of TNF-alpha in a cell culture of mouse peritoneal macrophages incubated with three concentrations (25, 50, and 100 mg/ml) of two endodontic sealers was measured. The solutions containing the calcium hydroxide-based root canal sealer (Sealapex) released fewer units of TNF-alpha than solutions containing the zinc oxide and eugenol-based sealer (Endomethasone).  相似文献   
83.
BACKGROUND: Current outcome results with embryos derived from thawed MII human oocyes are significantly lower than with embryos cryopreserved at the pronuclear stage. Here, we investigated whether freezing-thawing was associated with changes in oocyte mitochondrial polarity (DeltaPsim) that could influence competence by altering ATP levels or the ability of the cytoplasm to regulate intracellular Ca2+. METHODS: Fresh and thawed uninseminated and unfertilized MII oocytes were stained with the DeltaPsim-specific probe JC-1 to detect clusters of high-polarized mitochondria (J-aggregate positive) and with the Ca2+- specific probe Fluo-4 to measure changes in intracellular levels of this cation. ATP content per oocyte was measured directly and cortical granules were visualized with a cortical granule-specific probe. RESULTS: A significant difference between fresh and thawed MII oocytes existed for pericortical J-aggregate fluorescence and for the ability of the cytoplasm to increase free Ca2+ in response to ionophore exposure. No significant difference in ATP contents was measured and cryopreservation was not associated with an apparent release of cortical granules. CONCLUSION: Irreversible loss of high DeltaPsim in thawed oocytes may be associated with defects in Ca2+ signalling after insemination and could have downstream consequences for normal embryogenesis.  相似文献   
84.
Glycogen storage diseases are a rare group of disorders in daily pediatric practice but must be taken into account when a patient presents with poor physical growth, hepatomegaly, hypoglycemia, hypotonia and/or other metabolic disturbances. Early diagnosis allows treatment that might improve the patient's outcome to be started or, at the very least, genetic counseling to be given to the parents. We present a 10-month-old boy who presented with growth retardation, abdominal distention and hepatomegaly and who was finally diagnosed with glycogenosis type IX. Definitive diagnosis was obtained by demonstrating the enzyme defect (phosphorylase beta-kinase) in affected tissues. Enteral nutrition was started using a diurnal high-carbohydrate diet with frequent feedings and nocturnal nasogastric continuous feeding, achieving optimal growth parameters and clinical response.  相似文献   
85.
The efficacies of specific Bothrops atrox-Lachesis and standard Bothrops-Lachesis antivenoms were compared in the north eastern Amazon region of Brazil. The main aim was to investigate whether a specific antivenom raised against the venom of B. atrox, the most important Amazon snake species from a medical point of view, was necessary for the treatment of patients in this region. Seventy-four patients with local and systemic effects of envenoming by Bothrops or Lachesis snakes were randomly allocated to receive either specific (n = 38) or standard (n = 36) antivenoms. In 46 cases (24 in the standard antivenom group, 22 in the other) the snake was identified either by enzyme immunoassay or by examination of the dead snake, as B. atrox in 45, L. muta in one. Patients were similar in all clinical and epidemiological respects before treatment. Results indicated that both antivenoms were equally effective in reversing all signs of envenoming detected both clinically and in the laboratory. Venom-induced haemostatic abnormalities were resolved within 24 h after the start of antivenom therapy in most patients. The extent of local complications, such as local skin necrosis and secondary infection, was similar in both groups. There were no deaths. The incidence of early anaphylactic reactions was 18% and 19%, respectively for specific and standard antivenoms; none was life-threatening. Measurement of serum venom concentrations by enzyme immunoassay (EIA) confirmed that both antivenoms cleared venom antigenaemia effectively. EIA also revealed that one patient had been bitten by Lachesis muta, although the clinical features in this case were not distinctive.  相似文献   
86.
BACKGROUND: Little is known about the perception of mental disorders and stigma in developing countries. The aim of this study was to review the literature on popular perception of mental disorders in Latin America and the Caribbean. METHODS: Electronic search was made on Medline and Lilacs for original articles published from January 1980 to December 2001, using "public attitudes" and "mental disorders" as key words on Medline and "attitudes about health" as well as "stigma" as key words on Lilacs. In addition, a manual search was conducted in the references of the articles obtained in the electronic search and in area periodicals. RESULTS: The search produced 871 articles, ten of which fulfilled the inclusion criteria. Attitudes in relation to the mentally ill are predominantly positive, especially among individuals with a higher educational or socioeconomic level. Schizophrenia is the condition most often identified as mental illness and considered the most serious affliction. Depression and alcoholism are identified as mental illnesses by a smaller portion of the population. The community mostly recommends treatment with health professionals. CONCLUSION: In Latin America and the Caribbean, there is a tendency to share the beliefs of the western medical model and few signs of the presence of elements from traditional medicine or religion. However, the studies exhibited various methodological gaps and problems. New studies, using more appropriate methodology, should be carried out in this region.  相似文献   
87.
The nucleus pretectalis (PT) of birds is an ovoid-shaped visuomotor cell group of the pretectum that receives tectal input and projects back to the optic tectum. We performed immunohistochemical single- and double-labeling to determine the distribution and abundance of neurons containing three calcium-binding proteins, parvalbumin (PV), calretinin (CR), and calbindin (CB), in the PT in chickens at three ages. We found that PV-positive and CR-positive cells co-localize and are largely found in the outer part of PT at all ages. The GluR4 subunit of the AMPA-type glutamate receptor was selectively localized to these neurons. CB-positive neurons, however, were largely absent from the PT in young and adult chickens. The abundance of PV-positive and CR-positive neurons in PT in old birds was indistinguishable from that in the younger birds, but CB-positive perikarya were 10-20-fold more common than in young birds, and were again mainly found in the outer part of PT. The overall abundance of neurons in PT was reduced to about 50% of its former abundance in the old birds, with this loss restricted to the central part of the nucleus. These data indicate that a cell loss process develops in PT as birds age, that parvalbuminergic and calretinergic neurons resist this process, and that this process is associated with increased expression of CB.  相似文献   
88.
Meniere's disease can compromise the quality of life of some patients in a manner so seriously that it can cause social segregation, even from family. Hearing loss, tinnitus, aural pressure, and disturbances in equilibrium added to an emotional instability frequently present in these patients may take them to a progressive state of solitude and depression, marking their lives by personal tragedy and making life a living hell. The clinical picture of Meniere's disease fluctuates, however. Individually, subsidiary examinations become impotent in diagnosing Meniere's disease. To be called Meniere's disease, the cause must be unknown; otherwise it would constitute Meniere's syndrome. Taking all of this into consideration, one would call this an unusual situation, or at least confusing. The lack of an etiologic diagnosis in medicine always creates anxiety for doctors and patients. What is considered to be either a routine or an extended test may change from service to service. The physician does not need to order all tests. What the physician needs is a protocol he or she trusts. Test results can vary, even depending on the moment when they are performed. More important than the number of tests ordered is the strategy by which the tests should be put together at that certain moment. The authors believe that one should have his or her own protocol for diagnosis, always beginning with a detailed history taking being guided by them most of the time. It is the authors' understanding that patients with Meniere's disease should be followed closely by their ear, nose, and throat doctor in episodes of vertigo or fluctuation of their hearing, tinnitus, or aural pressure. Should the patient be experiencing a stable period, a clinical visit along with an audiovestibular workup should be performed at least once a year. By monitoring the course of the disease, clinicians would be able to detect early changes in symptoms and/or test results, giving them the possibility to intervene clinically as early as possible in acute episodes of vestibulocochlear disorganization, protecting the inner ear, and minimizing sequelae from spells of hydrops. The authors believe that only the association of clinical sense and as many subsidiary tests as are useful will lead to a desirable level of certainty in the diagnosis of Meniere's disease, and will allow clinicians to presume bilateral involvement, monitor the development of the disease, intervene in its natural course, and idealize appropriate treatment.  相似文献   
89.
BACKGROUND: The first prospective clinical Flu Vaccination in Acute Coronary Syndromes (FLUVACS) Trial has provided some evidence that flu vaccination together with standard therapy may be useful during the winter season to reduce the risk of death and major cardiac events in patients with acute myocardial infarction. PATIENTS AND METHOD: Information available in the FLUVACS database was analyzed to evaluate the efficacy of flu vaccination in different subgroups. Logistic regression was used to identify features related with better therapeutic results. RESULTS: Flu vaccination was effective in reducing the incidence of the composite endpoint (death, nonfatal myocardial reinfarction or recurrent angina prompting urgent revascularization) in most subgroups at 6 months after inclusion. The regression model showed a greater benefit of flu vaccination in patients with no ST-segment elevation or older than 65 years, nonsmokers and patients with a TIMI risk score higher than 6. CONCLUSIONS: Our data suggest that vaccination for secondary prevention of flu during the acute phase of myocardial infarction may be effective in a broad range of patients with acute coronary artery disease, regardless of their initial clinical risk.  相似文献   
90.
BACKGROUND: Liver disorders are the major manifestations of schistosomiasis mansoni. Factors that account for increased concentrations of cholestasis-indicating enzymes in the hepatosplenic form of the disease are unknown. OBJECTIVE: To assess the correlation between increased gamma-glutamyltransferase serum levels and both the parasitic load and ultrasound alterations in patients with schistosomiasis. PATIENTS AND METHODS: Twenty-five patients with the chronic form of schistosomiasis were assessed for the presence or absence of increased enzymatic levels, for the parasitic load (low x medium/high) and for ultrasound parameters. Furthermore, analysis of prothrombin time and a platelet count were performed. RESULTS: Of the 25 patients, 13 showed increased gamma-glutamyltransferase plasma levels. No significant correlation was found between increased gamma-glutamyltransferase levels and the parasitic load, or between increased enzyme levels and ultrasound alterations. Nor did the prothrombin index or the platelet count differ between the two groups (normal gamma-glutamyltransferase levels and increased gamma-glutamyltransferase levels). CONCLUSION: The parasitic load explains no rise in gamma-glutamyltransferase plasma levels in patients with the chronic form of schistosomiasis, and conventional ultrasound is not a sensitive method to detect the alteration suggested by the increased enzyme level in those patients.  相似文献   
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