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An unusual case of heteropagus twinning.   总被引:1,自引:0,他引:1  
A 3-day-old boy baby presented with a cystic umbilical swelling covered mostly by skin and partly by amnion. On the surface, an early embryo-like structure was attached (facial features and limb buds). The deeper aspect of it was composed of large cystic and tubular structures and solid organs resembling liver and spleen. It was labeled as acardiac amorphous parasitic twin, the first of its kind to be reported.  相似文献   
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The effect of increasing haemoglobin by erythropoietin therapy on exercise capacity was investigated in 11 regular haemodialysis patients, previously transfusion dependent. Exercise work load increased from a median of 100 W (95% confidence limit, 25-135) to 120 (45-180; p < 0.05) following erythropoietin, and the duration of the exercise test from 13 (3.5-20) to 15.5 min (4-22; p < 0.05). Resting blood lactate concentration decreased from 0.8 (0.6-1.6) to 0.3 mmol/l (0.3-0.4), p < 0.05, following treatment with erythropoietin, as did blood lactate concentration at maximal exertion from 2.0 (1.0-4.1) to 1.8 mmol/l (0.5-2.8; p < 0.05). In association with the increase in haemoglobin from a median of 6 (5.1-6.8) to 11.1 g/dl (11-11.9) following erythropoietin therapy, patients were able to achieve greater exercise capacity both in terms of maximum work load and duration of exercise in association with a reduced resting arterial lactate and a similar exercise-induced lactate production. This suggests that treatment had improved muscle function in terms of lactate production and/or utilisation. This was probably due to the increase in tissue oxygen delivery, as there was an increase in the median arterial oxygen content from 79 (65-85) to 150 ml O2 (144-157) following erythropoietin treatment.  相似文献   
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Dengue is a mosquito-borne viral disease caused by four antigenically distinct serotypes of dengue viruses (DENVs). This disease, which is prevalent in over a hundred tropical and sub-tropical countries of the world, represents a significant global public health problem. A tetravalent dengue vaccine capable of protecting against all four DENV serotypes has been elusive so far. Current efforts are focused on producing a tetravalent vaccine by mixing four monovalent vaccine components. In this work, we have utilized a discrete carboxy-terminal region of the major DENV envelope (E) protein, known as domain III (EDIII), which mediates virus entry into target cells and contains multiple serotype-specific neutralizing epitopes, to create a chimeric tetravalent antigen. This antigen derived by in-frame fusion of the EDIII-encoding sequences of the four DENV serotypes was expressed using a replication-defective recombinant human adenovirus type 5 (rAdV5) vaccine vector. This rAdV5 vector induced cell-mediated immune responses and virus-neutralizing antibodies specific to each of the four DENVs in mice. Interestingly, anti-AdV5 antibodies did not suppress the induction of DENV-specific neutralizing antibodies. We observed that anti-AdV5 antibodies in the sera of immunized mice could promote uptake of a rAdV5-derived reporter vector into U937 cells, suggesting that pre-existing immunity to AdV5 may in fact facilitate the uptake of rAdV5 vectored vaccines into antigen presenting cells. This work presents an alternative approach to developing a single component tetravalent vaccine that bypasses the complexities inherent in the currently adopted four-in-one physical mixture approach.  相似文献   
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The effect of mammalian insulin was studied in a freshwater fish, Clarias batrachus, at both high and low ambient temperatures. The hormone produced a significant but delayed, yet recoverable, lowering of blood glucose, a concurrent decrease in liver glycogen, and an increase in the glycogen content of muscles. The decrease in brain glycogen occurred during advanced hypoglycemia. Hypoglycemic seizures developed intermittently in most of the fishes whose plasma glucose and brain glycogen levels had been considerably depleted. Necrobiotic changes in the pancreatic islets, including degranulation and atrophy, and necrosis of B cells, were seen in the treated fish. In some cases damage to A cells and the acinar tissue was also observed. With the restitution of normal glucose and glycogen values, the islet cells also seemed to have recuperated. Changes in glycemia, glycogen, and the islets were more pronounced in the fishes held at 24 degrees C than in those at 10 degrees C, indicating that the ambient temperature plays an important role in blood glucose homeostasis as well as insulin.  相似文献   
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Human adenoviruses (AdV) have been implicated in a wide variety of diseases and are ubiquitous in populations worldwide. These agents are of concern particularly in immunocompromised patients, children, and military recruits, resulting in severe disease or death. Clinical diagnosis of AdV is usually achieved through routine viral cell culture, which can take weeks for results. Immunofluorescence and enzyme-linked immunosorbent assay-based techniques are more timely but lack sensitivity. The ability to distinguish between the six different AdV species (A to F) is diagnostically relevant, as infections with specific AdV species are often associated with unique clinical outcomes and epidemiological features. Therefore, we developed a multiplex PCR-enzyme hybridization assay, the Adenoplex, using primers to the fiber gene that can simultaneously detect all six AdV species A through F in a single test. The limit of detection (LOD) based on the viral 50% tissue culture infective dose/ml for AdV A, B, C, D, E, and F was 10(-2), 10(-1), 10(-1), 10(-2), 10(-1), and 10(-2), respectively. Similarly, the LOD for the six DNA controls ranged from 10(2) to 10(3) copies/ml. Twelve common respiratory pathogens were tested with the Adenoplex, and no cross-reactivity was observed. We also validated our assay using clinical specimens spiked with different concentrations of AdV strains of each species type and tested by multiplex PCR and culture. The results demonstrated an overall sensitivity and specificity of Adenoplex of 100%. This assay can be completed in as few as 5 h and provides a rapid, specific, and sensitive method to detect and subtype AdV species A through F.  相似文献   
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