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Since 1975, our experience in the treatment of biliary atresia with Kasai's technique has improved little by little, achieving 65% favourable outcome in the last five years. We define "good results" as the complete restoration of biliary flow and normalization of bilirrubin levels. The long-term evolution of these good results can be diverse. The objective of the present work is to analyze the outcome of patients in our series in whom a favourable initial response was achieved, as well as evaluating their present situation and future perspectives. The authors present a total of 17 patients operated by Kasai's technique since 1985, that constitutes the group with good results in our series. The controls were based on general analysis, liver function and periodic ultrasound explorations. All received a standardized medical treatment consisting of vitamin supplements (A, D3, E, K) minerals (zinc, calcium, phosphate, iron) ursodexoxicolic acid, luminal,as well as close control of calorie intake. In two patients the levels of bilirrubine were progressively increased with time, stabilizing at between 5/6 mgs/100 ml, with progressive hepatic hardening, appearance of splenomegalia, indirect signs of portal hypertension and a slight deterioration of hepatic function. One received a transplant at age 12 with Quick levels below 50%. The other, aged 16, continues with an acceptable hepatic function and good quality of life under recommendation of transplant. Eleven patients with ages ranging from fourteen months to seventeen years presented slight and firm hepatomegalia, moderate portal hypertension, GOT 71 +/- 8 mg/100 ml, GPT 97 +/- 11 mg/100 ml and normal bilirrubine levels. From this group, 3 patients, all under five years of age, experienced bleeding from esophageal varices which were controlled by sclerosis and medical treatment (propanolol and isosorbide dinitrate). Recently, one three year-old patient developed a hepatocarcinoma of rapid, mortal evolution. Since then, the determination of alfa-feto protein in follow-up controls has been introduced. Four other patients of 5, 6, 14, 16, years of age are completely assymptomatic with an excellent clinical evolution. In our experience,the patients that overcome the third year after surgery without serious complications seem destined to reach puberty with a good quality of life. However, some cases show signs of hepatic fibrosis and portal hypertension, 77% in our series. Only 23% of patients with a favorable initial evolution appear to present a complete normalization of their hepatic lesion in the long term.  相似文献   
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In vitro subculturing of the yeastlike form of Paracoccidioides brasiliensis strain IVIC Pb9 leads to the disappearance of alpha-1,3-glucan as a main component of its cell wall. However, the addition of fetal calf serum to the growth medium induces the synthesis of this polysaccharide. It is suggested that the synthesis of alpha-1,3-glucan in the cell wall of the yeastlike form of P. brasiliensis is induced by external factors.  相似文献   
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Summary Background. In patients presenting brain metastases as the first manifestation of a previously undiagnosed primary tumour (UDP) histopathological confirmation of the diagnosis can be obtained by either direct surgical sampling of the brain lesion or paraclinical search for an accessible primary tumour. The sequence of the diagnostic work-up and the timing of an eventual neurosurgical intervention are a matter of debate and are mainly influenced by the distribution of primary tumours in UDP patients. The aim of this study was to verify the hypothesis that the distribution of primary tumours differs between UDP patients and the rest of the patients with brain metastases (DP), and to propose a diagnostic work-up specifically tailored to the UDP population.Methods. Retrospective study on 342 patients admitted to the Lausanne University hospital between 1983 and 1998 with the diagnosis of cerebral metastases.Findings. UDP patients represented 36% of the whole group. Primary tumour location was significantly different between the two groups (p=0.001). Although the lung was the most frequent primary tumour location in both groups (UDP: 60%, DP: 43%), in UDP 14% only of the primaries were found outside of the lung and as much as 26% remained unknown despite thorough investigations.Conclusions. Our study confirmed the hypothesis that the relative frequency of primary tumours differs between DP and UDP patients. This difference therefore mandates a diagnostic strategy specifically tailored for UDP patients: if a radiological lung investigation clearly remains the best initial step in the work-up of these patients, extensive paraclinical investigations without a clear clinical suspicion should probably not be undertaken if this first survey fails to disclose the primary tumour as only 14% of the patients will actually benefit from it. In this situation, a neurosurgical procedure should probably be considered the most appropriate next step to be taken in order to provide a definitive diagnosis without unnecessary delays.  相似文献   
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OBJECTIVE: To determine the effects of a multidisciplinary weight reduction program on body composition and energy expenditure (EE) in severely obese adolescents. RESEARCH METHODS AND PROCEDURES: Twenty-six severely obese adolescents, 12 to 16 years old [mean BMI: 33.9 kg/m(2); 41.5% fat mass (FM)] followed a 9-month weight reduction program including moderate energy restriction and progressive endurance and resistance training. Body composition was assessed by DXA, basal metabolic rate by indirect calorimetry, and EE by whole-body indirect calorimetry with the same activity program over 36-hour periods before starting and 9 months after the weight reduction period. RESULTS: Adolescents gained (least-square mean +/- SE) 2.9 +/- 0.2 cm in height, lost 16.9 +/- 1.3 kg body weight (BW), 15.2 +/- 0.9 kg FM, and 1.8 +/- 0.5 kg fat-free mass (FFM) (p < 0.001). Basal metabolic rate, sleeping, sedentary, and daily EE were 8% to 14% lower 9 months after starting (p < 0.001) and still 6% to 12% lower after adjustment for FFM (p < 0.05). Energy cost of walking decreased by 22% (p < 0.001). The reduction in heart rate during sleep and sedentary activities (-10 to -13 beats/min), and walking (-20 to -25 beats/min) (p < 0.001) resulted from both the decrease in BW and physical training. DISCUSSION: A weight reduction program combining moderate energy restriction and physical training in severely obese adolescents resulted in great BW and FM losses and improvement of cardiovascular fitness but did not prevent the decline in EE even after adjustment for FFM.  相似文献   
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As an environmental protection point of view, the potential toxicity of chitosan on aquatic animal health, alone or associated with copper must be investigated. Fish possess defence mechanisms to counteract the impact of toxics. The non-cellular and non-specific immune defences (total immunoglobulin, ceruloplasmin, lysozyme and potential killing activity of phagocytic cells) can be modulated by the potential environmental pollutants but also by natural stimulants such as bacteria, viruses or parasites. In this study, we investigate the potential toxicity of copper (0.1 and 0.25 mg/L) or chitosan (75 and 150 mg/L) and the combination copper and chitosan (0.1 and 75 mg/L, respectively) on two groups of carp: healthy or parasitised by Ptychobothrium sp. Fish exposed to water-soluble chitosan for 96 h had significantly high levels of natural antibodies in plasma. Moreover, activities of lysozyme and ceruloplasmin were also increased in plasma after the same treatment. The exposition of fish to copper have shown apparently contradictory effects on the immune parameters measured but, significant increase of this bacteriolytic activity was observed, particularly in head kidney after 4 days of treatment of fish with copper. The two products may induce separately an acute, short and local inflammatory acute phase response by stimulating some components of the innate immune response of healthy fish. The mixture seems to reduce the impact of the each product due to the physical and chemical properties of chitosan to complex with copper. The responses of humoral immune factors of treated carp was modulated by the presence of the parasite, as shown by the high elevation of lysozyme activity observed in parasitised carps after exposition to copper and by increases in natural antibodies levels observed in parasitised carp treated with the copper-chitosan mixture. This could indicate an additive effect on the stress response mediated by parasite. It occurred a greater stress response in the parasitised group than healthy group exposed to the same treatment evoking an additive effect. So, it is important to specify the health status of organisms to understand responses of immunological markers in fish.  相似文献   
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Three new cyanobiphenyl polysiloxanes presenting long thioether spacers have been carried out. This type of spacer leads to very stable liquid‐crystalline polymers at room temperature and remove the crystallinity phenomenon. Dielectric analysis results show that the thioether spacer brings much more molecular flexibility to the system.

Example of an “interdigitated” structure observed by X‐ray analysis.  相似文献   

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