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Opportunistic fungal infections are becoming more frequent complications during cancer therapy, after organ transplantation and in AIDS infections, especially after better control of bacterial infections in immunocompromised patients. Periods of prolonged neutropenia with neutrophil count less than 0.5 x 10(9)/L longer than 7 days, are the most important risk factors for the development of systemic fungal infections. Especially susceptible are the patients during treatment of acute leukemia, or after bone marrow transplantation. The most frequent causing agents of systemic fungal infections are Candida and Aspergillus species, than Cryptococcus neoformans and Mucor. Some other unusual species such Fusarium, Trichosporon, non-albicans Candida species of Candida are becoming more frequent, and is frequently resistant to conventional therapy. The difficulties in early and precise diagnosis of fungal infections, and the lack of adequate and efficient drugs are responsible for the high mortality of immunocompromised patients, even in potentially curable diseases. The recognition of risk factors, introduction of prophylactic measures, application of empirical antifungal therapy, are the procedures for the reduction of morbidity and mortality of invasive fungal infections. Fluconazole administration in prevention of systemic fungal infections, has become the standard approach, especially after bone marrow transplantation, while the oral itraconazole solution, has even more extended activity. Fluconazole appears successful also in the treatment of systemic Candidiasis. Conventional amphotericin-B is still the "gold standard" in the treatment of fungal infections. The new lipid formulations of amphotericin-B, intravenous itraconazole, has an identical efficacy, but are less toxic than conventional amphotericin-B. Several new promising agents are in the stage of clinical investigation like voriconazole, caspofungin, mycafungin and some other.  相似文献   
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Left Bochdalek hernia is a serious and complex condition with high mortality. In most cases, it presents in the neonatal period and is seldom found later in life when symptomatology, usually after an asymptomatic period, is quite different and the prognosis excellent. The embryological development of left Bochdalek hernia suggests the presence of abdominal content in the left pleural cavity before birth. The type of clinical presentation and the prognosis depend on the time of visceral herniation. This study presents two cases of left Bochdalek hernia with delayed presentation. In both cases, after surgical reposition of the hernia, a small congenital diaphragmatic defect was found hidden between the rims of diaphragm. This indicates the possibility for the abdominal content to enter the left pleural cavity at the time of presentation.  相似文献   
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Variation of the photoactivation rate across radiation fields of three different bremsstrahlung beams of two medical accelerators has been measured, making use of the photonuclear reactions in natural indium probes: 115In(y,y')115mIn and 115In(y,n)114mIn. The third nuclear reaction, 115In(n,y)116mIn, was used to detect the presence of neutrons in the photon beam and to estimate the spatial distribution of thermal and fast neutrons in the patient plane as a function of collimator opening.  相似文献   
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Anatomical variations in the dimensions of different brain structures have been correlated with clinical syndromes. This study on the parameters of normal and abnormal cavum septi pellucidi (CSP) can be of clinical significance. We obtained 479 brains from autopsied persons (310 males and 169 females, 377 normal or asymptomatic and 102 abnormal or symptomatic persons, aged 22-89 years) and observed that 110 brains (75 males and 35 females) had CSP. These cava were classified into two groups depending on the past medical histories of the autopsied person: 40 asymptomatic and 70 symptomatic cava. We have defined symptomatic cava as those in autopsied persons who had known past medical history of psychiatric or neurological disease. Asymptomatic cava were in autopsied persons who had no known past medical history of psychiatric or neurological disease. The CSP parameters (length, width, depth) of the symptomatic and asymptomatic groups were measured and were statistically analyzed. Analysis showed that the cava in the symptomatic group were significantly longer and wider. Discriminant function analysis was used to derive a mathematical formula to classify CSP into an asymptomatic or symptomatic group based on length and width measurements of the cavum.  相似文献   
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