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31.
Radioimmunoassay techniques were used to detect antibodies to the acetylcholine receptor (AAChR) in 164 patients with adult-onset myasthenia gravis. AAChR levels above 0.6 nM/l were considered pathological and were found in 67% of the patients with an average value of 58.99 +/- 125.02 nM/l (0.6-900.0). Correlation, with clinical functional status, the histopathological thymus alterations and the different therapeutics used did not disclose any statistically significant differences.  相似文献   
32.
CONTEXT AND OBJECTIVE: Adverse drug reactions are a significant problem in patients on antiretroviral therapy (ART). We determined liver enzyme elevation frequencies in HIV-infected children and adolescents receiving ART, and their association with risk factors. DESIGN AND SETTING: Cross-sectional study, at the Pediatrics Immunodeficiency Division, University Hospital, Universidade Estadual de Campinas. METHODS: Medical records of 152 children and adolescents (54.6% male; median age 7.48 years) were analyzed, with a mean of 2.6 liver enzyme determinations per patient. Clinically, patients were classified in categories N (6), A (29), B (78) and C (39). Serum levels of aspartate aminotransferase and alanine aminotransferase were evaluated. Hepatotoxicity was scored as grade 1 (1.1-4.9 times upper limit of normality, ULN), grade 2 (5.0-9.9 times ULN), grade 3 (10.0-15.0 times ULN) and grade 4 (> 15.0 times ULN). To assess hepatotoxicity risk factors, odds ratios (OR) and adjusted odds ratios (aOR) for age, gender, TCD4+ cell count, viral load and medication usage were calculated. RESULTS: We observed grade 1 hepatotoxicity in 19.7 % (30/152) patients. No cases of grade 2, 3 or 4 were detected. There was a significant association between hepatotoxicity and use of sulfonamides (OR, 3.61; 95% confidence interval (CI), 1.50-8.70; aOR, 3.58; 95% CI, 1.44-8.85) and antituberculous agents (OR, 9.23; 95% CI, 1.60-53.08; aOR, 9.05; 95% CI, 1.48-55.25). No toxicity was associated with ART. CONCLUSIONS: One fifth of patients experienced mild hepatotoxicity, attributed to antituberculous agents and sulfonamides. Our results suggest that ART was well tolerated.  相似文献   
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We report a postpartum acute myocardial infarction that occurred during the first week after cesarean section delivery. We also calculated the rate of postpartum myocardial infarction as related to all women with myocardial infarctions seen in our hospital.(Am J Obstet Gynecol 1997;177:1553-5.)  相似文献   
35.
Current newborn screening programs in California and most of the U.S. depend for diagnosis of congenital primary hypothyroidism on demonstrating an elevated thyrotropin (TSH) level in infants with the lowest 5% to 10% of thyroxine (T4) levels by filter-paper bloodspot test. The diagnosis of primary congenital hypothyroidism based on low T4 with high TSH fails to distinguish between transient hypothyroidism, ectopic or hypoplastic thyroid, athyrosis, dyshormonogenesis, and transient hyperthyrotropinemia. We screened 166,300 newborn infants for primary congenital hypothyroidism for 6.5 years and confirmed the diagnosis in 46 cases; none of these patients had a goiter. Thyroid scintigraphy was performed in 40 with technetium-99m (Tc-99m) in the first eight cases tested and iodine-123 (I-123) in 29 of the last 32 cases. Fifteen infants were athyroid and seven had ectopic or hypoplastic glands; in 18 the thyroid gland appeared normal (present, normal location). Congenital hypothyroidism represents a spectrum of diseases from transient underactivity to complete absence of the thyroid gland. We recommend that, before starting treatment, a specific anatomic and functional diagnosis be confirmed by thyroid scintigraphy and other thyroid function tests.  相似文献   
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Ischemia negatively affects mitochondrial function by inducing the mitochondrial permeability transition (MPT). The MPT is triggered by oxidative stress, which occurs in mitochondria during ischemia as a result of diminished antioxidant defenses and increased reactive oxygen species production. It causes mitochondrial dysfunction and can ultimately lead to cell death. Therefore, drugs able to minimize mitochondrial damage induced by ischemia may prove to be clinically effective. We analyzed the effect of carvedilol, a beta-blocker with antioxidant properties, on mitochondrial dysfunction. Carvedilol decreased levels of TBARS (thiobarbituric acid reactive substances), an indicator of oxidative stress, which is consistent with its antioxidant properties. Regarding cell death by apoptosis, although ischemia did increase caspase-8-like activity, there were no changes in caspase-3-like activity, which is activated downstream of caspase-8; this may indicate that the apoptotic cascade is not activated by 60 minutes of ischemia. We conclude that carvedilol protects ischemic mitochondria by preventing oxidative mitochondrial damage, and, by so doing, it may also inhibit the formation of the MPT pore.  相似文献   
38.
OBJECTIVE: The 5-year project in the province of Sofala was designed to improve access, quality and utilization of emergency obstetric care (EmOC) by strengthening rural hospitals and health centers and ultimately the health system's capacity to respond to emergencies more quickly and effectively. METHODS: Implementation consisted of attention to infrastructure, human resource development, transportation and communication systems, and management. Specific management aspects that were targeted for improvement included: supportive supervision, logistics for supplies, equipment and drugs, record keeping, monitoring and evaluation, and quality improvement techniques such as maternal death audits. RESULTS: Access to EmOC improved with an increase in the number of fully functional EmOC facilities from 4 to 18. The number of women with obstetric complications who were admitted for treatment in participating facilities tripled, and the proportion of those women dying declined by half. CONCLUSIONS: Close collaboration and partnership with the provincial health directorate make the sustainability of many results likely while the replication of much of the Sofala model to other provinces is promising for the national strategy to reduce maternal mortality.  相似文献   
39.
The human foot is a complex mechanical structure consisting of bones, ligaments and joints. They act together to provide a robust system capable of absorbing and dissipating the intermitted pressure that is subjected to its plantar surface during walking to prevent soft tissue breakdown. Current studies suggest that plantar foot pressure may lead to soft tissue breakdown (e.g. neuropathic ulceration) and hence research has so far concentrated on investigating the mechanical effects of plantar foot pressure on the foot’s integrity. This has been possible through the widely available pressure and force platforms as well as in-shoe pressure systems. However, to understand how plantar foot pressure causes soft tissue breakdown it is vital to investigate both the physiological–mechanical interactions between the skin and plantar foot pressure. This review suggests that with the current advances in technology, the physiological response of skin blood flow to mechanical plantar foot pressure should be investigated and correlated further, both during static and dynamic loading, by developing a new system capable of either measuring both variables simultaneously or by synchronising two systems in real time.  相似文献   
40.
Solitary thyroid nodule: diagnosis and management   总被引:1,自引:0,他引:1  
Thyroid nodules are common. Most are benign lesions since clinically important thyroid carcinoma is a relatively rare disease. The most sensitive and specific test for the diagnosis of thyroid cancer is fine-needle aspiration biopsy, but its diagnostic accuracy depends upon whether or not one excises all suspicious nodules, thus including them as correctly diagnosed. Nevertheless, fine-needle aspiration biopsy is the most sensitive, specific, and cost-effective test for thyroid cancer. Therapy depends upon the cause of the thyroid nodule.  相似文献   
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