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61.
Intracranial subdural hematoma is a rare, but potentially lethal complication of neuraxial procedures. Considering the high frequency of neuraxial techniques in the obstetric population, parturients are more susceptible to this fearful complication. The diagnosis is often masked and delayed because it shares similar clinical characteristics with posdural puncture headache, with headache being the most common symptom. This case report describes a timely diagnosis and successful management of an intracranial subdural hematoma, after unintentional dural puncture during labour epidural analgesia. Postpartum headache following epidural analgesia, remains a clinical challenge for the caring team, requiring a close follow-up and awareness for non-benign causes that require prompt management, avoiding devastating consequences.  相似文献   
62.
Transplantation of any organ has some inherent risk of disease transmission, such as infection and malignancy. The present study aims to describe 2 cases of choriocarcinoma transmission after kidney and liver transplantation originating from the same patient. The donor was a 17-year-old woman who died of cerebral hemorrhage. Both organ recipients died of metastatic choriocarcinoma few months after the transplantation, within days after starting chemotherapy. Retrospective hCG (human chorionic gonadotropin hormone) analysis in donor's blood stored at the time of donation had a result of 9324 mIU/mL. Despite its rarity, clinicians should be aware of the risk of transplant-related choriocarcinoma from female donors in childbearing age. In some cases, hCG dosage should be performed before donation.  相似文献   
63.

Although adolescents living on the street tend to have unprotected sex with many partners and substance abuse, little is known about this reality in Brazil. To estimate the prevalence and factors associated with risky sexual behavior among children and adolescents living on the street in Porto Alegre and Rio Grande. A cross-sectional study was carried out using the Respondent-Driven Sampling (RDS) sampling method to quickly and efficiently access populations of difficult access. Poisson regression with robust adjustment of variance was used in the multivariate analysis. The sample consisted of 231 participants aged 10–21 years. Most were male and aged 16- 21 years. More than half (66.7%) of the respondents did not have a school bond, and 64.5% did not live with the family. Half of the sample had been living on the street for at least four years, spending 15 h or more on the street. Most (86.6%) responded that they had already used illicit drugs in their lives, and unprotected sex prevalence was 61.9%. The variables independently associated with unprotected sex were years living on the street, hours spent on the street, having a steady partner, illicit drug use, and sexual intercourse without a condom under the influence of drugs. The high prevalence of unprotected sex points to the need for intervention policies for this population to prevent the main risk factors.

  相似文献   
64.
An estimated 400 million people are infected by parasites of the genus Ascaris and the existing control measures are inefficient. Vaccine development using B cell antigens is a promising strategy for increased protection against this parasite. The present study aimed at developing a chimeric protein capable of conferring protection against infection by Ascaris sp. For this purpose, we performed B-cell epitope predictions on previously described vaccine candidate proteins from Ascaris suum and the corresponding peptides were used to construct a chimeric protein. Female BALB / c mice were immunized subcutaneously in three doses at 10 day intervals with a vaccine formulation comprised of the chimeric protein together with monophosphoryl lipid A (MPLA). Control groups included protein alone, MPLA, or PBS. After challenge infection, animals vaccinated with chimeric protein plus MPLA showed a reduction of 73.54% of larval load in the lung compared to control group animals. Animals immunized with chimeric protein plus MPLA also display higher IgG response and a reduction in lung inflammation. Our study highlights how chimeric proteins containing more than one B cell epitope can enhance immune protection against helminthic infection and offer new approaches to the development of Ascaris vaccines.  相似文献   
65.
The placebo effect is a most curious phenomenon, which has been known since ancient times. After World War II, it became an important methodological tool in the conduction of clinical trials. The so-called "placebo-reactors" show special sensitivity to these inert substances. In general, 35.5 plus minus 2.2% of patients affected by various conditions proved to react positively to placebos. Several aspects of placebos seem to play a relevant potentiating action on such effects. In this context, surgical rather than clinical seems to be a more efficient placebo. Despite a clearcut role of the limbic system, emphasis has been placed on psychological aspects of the possible pathophysiologic mechanisms.  相似文献   
66.
The authors studied a sample of students entering the first grade in the Osasco public school system in order to determine both the prevalence of anemia and nutritional status. Osasco is part of the Greater S o Paulo Metropolitan Area. Diagnosis of anemia was made through the hemoglobin concentration of blood from digital puncture. World Health Organization (WHO) levels were used to define anemia. Nutritional Status assessment. was made through weight/age and height/age indices, using Z score distribution and the National Center for Health Statistics (NCHS) reference levels. Prevalence of anemia was 51%. Prevalence levels varied according to the schools' geographic location: 56.9% in peripheral neighborhoods and 41.7% in central areas. Children with illiterate parents had a higher prevalence of this condition. Risk of anemia was higher for children who were over eight years of age when entering the first grade. Acute malnutrition was not found. Prevalence was higher than expected and points to the urgent need to establish an anemia control program for schoolchildren in this population.  相似文献   
67.
The authors investigated the joint effects of tobacco and alcohol consumption on the risk of squamous cell carcinomas of the upper aero-digestive tract (UADT) using data from a hospital-based case-control study conducted in southern Brazil, 1986-1989. A total of 784 cases of cancers of the mouth, pharynx, and larynx and 1,578 non-cancer controls matched on age, sex, hospital catchment area, and period of admission were interviewed about their smoking and drinking habits and other characteristics. Using logistic regression, evidence was found for interaction between the cumulative exposures for smoking and alcohol on UADT cancer risk. The joint effects for pharyngeal cancers exceeded the levels expected under a multiplicative model for moderate smokers (p = 0.007). There was little statistical evidence, however, for interaction on cancers of the mouth (p = 0.28) or larynx (p = 0.95). Among never smokers, heavy drinkers had 9.2 times (95% confidence interval 1.7, 48.5) greater risk of cancers of mouth, pharynx, and supraglottis than never drinkers, with a dose-response trend (p = 0.013) with cumulative consumption. The authors conclude that the interaction occurring in the pharynx between smoking and alcohol on UADT cancers is not uniform, with varying effects depending on the level of smoking exposure. Alcohol may act as both a promoter for tobacco and as an independent risk factor.  相似文献   
68.
69.
In widespread informal gold mining in the Amazon Basin, mercury is used to capture the gold particles as amalgam. Releases of mercury to the environment have resulted in the contamination of freshwater fish with methylmercury. In four comparable Amazonian communities, we examined 351 of 420 eligible children between 7 and 12 years of age. In three Tapajós villages with the highest exposures, more than 80% of 246 children had hair-mercury concentrations above 10 microg/g, a limit above which adverse effects on brain development are likely to occur. Neuropsychological tests of motor function, attention, and visuospatial performance showed decrements associated with the hair-mercury concentrations. Especially on the Santa Ana form board and the Stanford-Binet copying tests, similar associations were also apparent in the 105 children from the village with the lowest exposures, where all but two children had hair-mercury concentrations below 10 microg/g. Although average exposure levels may not have changed during recent years, prenatal exposure levels are unknown, and exact dose relationships cannot be generated from this cross-sectional study. However, the current mercury pollution seems sufficiently severe to cause adverse effects on brain development.  相似文献   
70.
This paper discusses issues related to the regulation and rational use of thalidomide in Brazil, by means of a historical approach comprising three different stages. The first part is a historical review of the controversial drug since it was first synthesized, then marketed and subsequently banned during the 1950s and 60s, until the present, when an apparently irreversible process of rehabilitating the drug is under way. Brazilian experience with the use of thalidomide is described, emphasizing legal, political, and institutional work led by two social movements, the Brazilian Association of People with Thalidomide Syndrome (ABPST) and the Movement for Reintegration of People with Hansen's Disease (Morhan). The article describes the results and analyzes an active search of new cases in what is a second generation of thalidomide syndrome in Brazil. Finally, based on clinical and scientific evidence of thalidomide's therapeutic efficacy, the growth of social movements struggling both for and against authorization of the drug, and a restrictive regulation proposed by the Ministry of Health, the article discusses the implementation of policies for the regulation and rational use of thalidomide in Brazil.  相似文献   
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