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931.
OBJECTIVE: To identify socioeconomic, gynecological-obstetric and fetal factors associated with perinatal mortality. METHODS: A matched case-control study was carried out. Cases were newborns (born live or dead) that were born and died between 28 weeks gestation and 7 days of life. Controls were live newborns between 28 weeks gestation and 7 days of life. A total of 99 cases and 197 controls were studied. Data were obtained from the corresponding medical charts. Statistical analysis was performed using Stata 6.0 software. RESULTS: Mean maternal age was 24.82 years and mean newborn age was 37.78 weeks gestation with an average birth weight of 2,760 grams. Factors associated with perinatal mortality were: father's occupation as a farmer (adjusted odds ratio (OR)=3.31; 95% CI=1.26-8.66); high obstetric risk index (adjusted OR=10.57; 95% CI=2.82-39.66), cesarean birth (adjusted OR=2.75; 95% CI=1.37-5.51), five or more prenatal visits (adjusted OR=4.43; 95% CI=1.86-10.54) and preterm fetal maturity indices (PEG, APG, GEG) (adjusted OR=9.20; 95% CI=4.39-19.25). CONCLUSIONS: The risk factors associated with perinatal mortality found in the study are consistent with the findings reported in the international literature. These results show that prevention and control measures should be implemented to identify at risk pregnant women in order to lower perinatal mortality.  相似文献   
932.
Secretory immunoglobulin A (sIgA) is a primary factor responsible for preventing attachment of enteropathogens to gut epithelium in breastfeeding infants. We compared the frequency of sIgA to major surface antigens of enterohemorrhagic Escherichia coli (EHEC) in milk of 123 women from the United States and Mexico to determine whether regional differences existed in the frequency of antibodies to these surface antigens. In both groups of women, milk commonly has sIgA against various EHEC lipopolysaccharides, EspA, EspB, intimin, and less frequently against Shiga toxin. The study suggests that persons living in the United States are exposed to attaching/effacing enteropathogens more frequently than is generally assumed. The low frequency of antibodies to Stx1 (in 12% of Mexican and in 22% of U.S. samples) suggests that the rare appearance of hemolytic uremic syndrome in adults is not due to neutralization of toxin at the gut level. Only anti-EspA is found in most milk samples from both populations of women. EspA may represent a useful target for an immunization strategy to prevent EHEC disease in humans.  相似文献   
933.
PURPOSE: To describe an unusual case of idiopathic retinal vasculitis, aneurysms, and neuroretinitis (IRVAN) syndrome with rapid dynamics in the number and appearance of the aneurysms. DESIGN: Observational case report. METHODS: Clinical and angiographic data of the patient were reviewed. RESULTS: In the course of only 6 months, preexisting retinal aneurysms resolved while new ones appeared. Changes were observed in the shape and size of preexisting lesions. The resolution of lesions in eyes previously untreated by laser is reported for the first time. CONCLUSIONS: Vascular lesions in IRVAN syndrome may show an unusually rapid turnover. The resolution of aneurysms is a part of the natural course of the disease and may occur without previous retinal laser photocoagulation.  相似文献   
934.
935.
PURPOSE: To evaluate the human leucocyte antigen (HLA) class 1 (HLA-A and HLA-B) and HLA class 2 (HLA-DRB1 and HLA-DQB1) allele profiles in the susceptibility to cytomegalovirus retinitis (CMV-R) in patients with AIDS. METHODS: Cytomegalovirus retinitis was clinically diagnosed by indirect binocular ophthalmoscopy. Human leucocyte antigens class 1 were typed using a complement-dependent microlymphocytotoxicity assay, and HLA class 2 alleles were identified using amplified DNA hybridized to sequence-specific oligonucleotide primers. RESULTS: The frequencies of HLA class 1 antigens and HLA class 2 alleles observed in patients and controls were similar; however, HLA-A31 antigen was over-represented in patients with AIDS, independent of the presence of CMV-R. CONCLUSION: There was no association between HLA molecules/alleles and CMV-R in Brazilian patients with AIDS. However, the results support the role of the HLA system in the susceptibility to developing AIDS.  相似文献   
936.
Chronic liver disease is a considerable burden on society, being one of the three main causes of death in certain regions of Africa and Asia. Liver transplant is the only treatment option for cirrhosis, which is the end stage of many chronic liver diseases. This article reviews the preventable causes of cirrhosis and the preventive strategies which could be implemented in order to avoid the catastrophic consequences of cirrhosis. With small variations around the world, 70 to 80% of the end stage liver diseases are caused by excessive alcohol consumption and by viral hepatitis, both of which are potentially preventable. Excessive alcohol consumption has important public health consequences because of its involvement not only with cirrhosis, but also with motor vehicle accidents, unemployment, domestic violence etc. Among the viral causes, Hepatitis Virus B and C have the greatest impact on public health. Effective vaccine is available for Hepatitis Virus B and must be put in use. While a vaccine for Hepatitis Virus C is awaited, effective preventive strategies should be undertaken to avoid the preventable cases of end stage liver disease.  相似文献   
937.
Hepatitis C is the main cause of cirrhosis and hepatocellular carcinoma and the leading indication of liver transplantation. The aim of this article was to review specific epidemiological, clinical and therapeutic aspects of hepatitis C and their implication for the hepatologists belonging to liver transplantation services. These specific aspects were reviewed in the literature mainly using Medline. Data regarding the epidemiological, clinical and therapeutic aspects of hepatitis C are discussed, with emphasis on their consequences for the liver transplantation team. Hepatitis C is a challenge for hepatologists and for the liver transplantation team. The burden we observe today is the late consequence of infection that occurred in the past. Measures for early recognition of complications of liver disease are recommended. HCV treatment should always be performed before liver transplantation if possible, but if not, HCV recurrence should be recognized and treated early after transplantation.  相似文献   
938.
939.
Esophageal resection has undergone refinements over recent years, with improved outcomes. However, in-hospital mortality remains above 10% in developed countries and is below 5% in only a select group of hospitals. Morbidity remains high even in high-volume hospitals. We reviewed risk factors in esophageal resection. Pulmonary complications occur mainly in older patients and in those with pulmonary dysfunction, especially %FEV1 or hypoxia. Liver cirrhosis, squamous cell cancer, low patient volume, and cervical anastomoses also increase complication rates. Neoadjuvant chemoradiotherapy, which may be effective in squamous cell tumors, can also increase morbidity. The main cause of morbidity and mortality are pleuropulmonary complications. Also significant are anastomotic leak and esophageal conduit necrosis. A complex procedure such as esophageal resection is better served in specialized teams.  相似文献   
940.
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