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71.
The precise diagnosis of paracoccidioidomycosis, in most cases, is established by direct methods and indirect immunological tests. The latter method is reliant on the identification of the host's humoral responses, which are usually impaired or absent in patients with severe juvenile forms of the disease and in immunocompromised patients. Determining disease activity or assessing treatment responses by measuring antibody levels is difficult, since antibody titer may remain elevated or persist at stationary levels, even in the presence of clinical improvement. Consequently, there is a need for alternative tests aimed at the identification of circulating antigens. A modification of the standard hybridoma production method was used to raise a panel of murine monoclonal antibodies (MAbs) against the yeast form of Paracoccidioides brasiliensis. Of these, MAb PIB, directed against an 87-kDa determinant, was used to develop an inhibition ELISA (inh-ELISA) capable of detecting as little as 5.8 ng of circulating antigen per ml of serum. Sera from 46 patients with paracoccidioidomycosis or other mycoses and sera from healthy individuals were evaluated by the inh-ELISA; overall sensitivity was 80.4% (37 of 46 paracoccidioidomycosis patients tested positive), and specificity compared with that of normal controls from areas of endemicity was 81.4%. The inh-ELISA detected circulating antigen in 100% of patients with the acute form of paracoccidioidomycosis and in 83.3 and 60% of patients with the chronic multifocal and unifocal forms of paracoccidioidomycosis according to the patients' clinical presentation. These results indicate that the inh-ELISA with MAb PIB is effective in the detection of circulating antigen and that this test may be useful for monitoring responses to treatment and establishing disease prognoses.  相似文献   
72.
Because the risk factors for human immunodeficiency virus (HIV) infection and hepatitis B (HBV) are similar and therefore coinfection is not uncommon, a detailed histological and immunohistochemical study of chronic hepatitis B infection in a group of 20 HIV positive Caucasian males (who did not have AIDS) and 30 HIV negative controls were undertaken. Using both the conventional histological classification and the Knodell histological activity index it was shown that HIV negative patients were more likely to have active disease and also more scarring than HIV positive patients. Hepatitis B surface antigen (HBsAg) expression was not significantly different between the two groups but expression of hepatitis Be antigen (HBeAg) and HBV-DNA polymerase was greater in those who were HIV positive. HIV positive patients are therefore more likely to have immunohistochemical markers of active viral replication, although histologically, liver disease is less severe. These findings have important implications for assessing the biopsy specimens in this group of patients and for treatment strategies aimed at improving their immune function.  相似文献   
73.
Lesions of the articular surfaces of the knee have been managed by various techniques over the last 50 years. Surgical management has involved: excising the damaged area, refashioning the underlying bone to produce a fibrous response, and introducing allograft, autograft and synthetic materials to encourage a repair matrix. The techniques and their pitfalls are reviewed and discussed, and suggestions made as to the direction of future studies for the repair of osteochondral lesions in the painful knee.  相似文献   
74.
Shunt surgery in children suffering from portal hypertension (PH) is considered as an immediate and definite mode of prevention of recurrent gastrointestinal hemorrhage. Certain conditions must be met: (a) normal liver; (b) normal veins available within the portal system; (c) a sufficient portosystemic gradient of pressure; and (d) a surgical team with experience in portal venous surgery. In patients in whom PH is an epiphenomenon of severe liver disease, other means of hemostasis for bleeding esophageal varices should be sought. The difficult decision is in the child with specific liver alterations without major hepatocellular dysfunction but in whom the prognosis cannot be precisely foreseen. A few more years will be needed before one can tell if shunt surgery is the best choice for this category of patient.
Resumen La cirugía derivativa (shunts portosistémicos) en los niños que sufren de hipertensión portal es considerada como una forma inmediata y definitiva de prevenir la hemorragia gastrointestinal recurrente. Ciertas condiciones deben existir para su realization: (a) hígado normal; (b) venas disponibles dentro del sistema porta; (c) suficiente gradiente en las presiones portosistémicas; y (d) disponibilidad de un equipo quirúrgico con experiencia en cirugía venosa portal. Otros medios de hemostasis de las várices esofágicas sangrantes deben ser utilizados en aquellos pacientes en quienes la hipertensión portal es un epifenómeno de enfermedad hepática severa. La decisión más difícil se presenta en el niño con alteraciones hepáticas específicas pero sin mayor disfunción hepatocelular en quien no se puede determinar con precisión el pronóstico. Todavía serán necesarios unos años más antes de poder afirmar que la cirugía derivativa representa la mejor escogencia para esta categoría de pacientes.

Résumé La dérivation portale chez les enfants atteints d'hypertension portale constitue une méthode immédiate et définitive de prévention des hémorragies digestives récidivantes. Les conditions les plus favorables sont les suivantes: a) foie normal; b) veines disponibles dans le secteur porte pour l'anastomose; c) gradient de pression suffisant entre le système porte et le système cave et d) équipe entraînée à la chirurgie portale. Lorsque l'hypertension portale est un épiphénomène au cours d'une affection hépatique sévère, d'autres méthodes d'hémostase des varices oesophagiennes rompues doivent être envisagées. La décision du choix thérapeutique à adopter est difficile lorsqu'il existe une atteinte hépatique, sans altération hépatocellulaire majeure, mais de pronostic incertain à long terme. Quelques années encore seront nécessaires avant de pouvoir affirmer que la dérivation représente la meilleure opération pour traiter ce type d'hypertension portale.
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75.
76.
I D Hay  C S Grant  W F Taylor  W M McConahey 《Surgery》1987,102(6):1088-1095
From a multivariate analysis of more than 14,200 patient-years' experience with papillary thyroid carcinoma (PTC), we devised a prognostic scoring system based on patient age, tumor grade, extent, and size (AGES). This scoring system can identify patients at increased risk of PTC mortality and was employed as an adjustment variable for analyzing the role of different types of surgical treatment in 860 PTC patients. Cancer mortality at 25 years in patients with an AGES score of 3.99 or less was 1% after ipsilateral lobectomy (n = 131) and 2% after bilateral resection (n = 603), whether subtotal or total (p = 0.15). Of patients with an AGES score of 4 or more, those who underwent lobectomy alone (n = 30) had a mortality rate from PTC at 25 years of 65%, while those undergoing bilateral resection (n = 86) had a lower rate of 35% (p = 0.06). For patients at minimal risk (score of 3.99 or less) of PTC death, no improvement in survival was demonstrable when patients underwent more than ipsilateral lobectomy. However, in a subgroup (score of 4 or more) identified to be at significant risk of PTC death, the survival after bilateral resection was much higher than after ipsilateral lobectomy alone. In neither the "minimal" nor the "higher" risk subgroup was PTC survival significantly improved by the performance of total thyroidectomy.  相似文献   
77.
Between about ages 40 and 55 years, women experience a transition known as the menopause, which marks the end of their childbearing years. Although the most striking feature of the menopause is the cessation of menstruation, other biologic and psychosocial events occur and can be classified as stressors and "facilitators". For a predisposed group of women the stressors are likely to cause psychiatric disorders. At the same time, the facilitators are opportunities for personal growth and development. Physicians who understand both types of events during this phase of life and who are sensitive to the overall effects of ageing on marital partners can provide comprehensive care to the menopausal patient rather than automatically pursuing drug therapy (substitution hormonal therapy) alone.  相似文献   
78.
79.
Journal of Prevention - Understanding the behaviors that lead to sunburn is an important objective toward developing intervention strategies to reduce risk for skin cancers. Our cross-sectional...  相似文献   
80.
Orthorexia nervosa is a new syndrome that has seen a marked increase in research in the past decade. Very high prevalence estimates in non-clinical populations have fuelled the debate as to whether it is a disorder in its own right, or only a problem when occurring in the context of another mental health or eating disorder. More recent assessment instruments have gone some way to address this issue. However, He et al.'s (2020, International Journal of Eating Disorder) study in older East Asian persons was not supportive of orthorexia nervosa as a disorder. Rather, people with orthorexia nervosa had better physical and mental health and lower or similar levels of eating disorder features such as body dissatisfaction when compared with people who did not have orthorexia nervosa. Albeit that selection bias in participant recruitment may in part explain their findings, the status of orthorexia nervosa is unresolved. Further studies need to employ appropriate instruments that measure psychopathology and function more broadly and investigate people with orthorexia nervosa symptoms in representative populations with longitudinal designs. The last is critical, as the most compelling evidence supporting a disorder is to find an adverse health impact over time that can be avoided by appropriate intervention.  相似文献   
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