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1.
There is a sharp difference in how one views TCR structure–function–behaviour dependent on whether its recognition of major histocompatibility complex‐encoded restriction elements (R) is germline selected or somatically generated. The generally accepted or Standard model is built on the assumption that recognition of R is by the V regions of the αβ TCR, which is not driven by allele specificity, whereas the competing model posits that recognition of R is allele‐specific. The establishing of allele‐specific recognition of R by the TCR would rule out the Standard model and clear the road to a consideration of a competing construct, the Tritope model. Here, the case for allele‐specific recognition (germline selected) is detailed making it obvious that the Standard model is untenable.  相似文献   
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The sonographic appearance of prostatic carcinoma was correlated with the corresponding histopathologic studies in 57 patients after transperineal biopsy. In 21 cases the lesions observed were less than or equal to 2 cm (circumscribed) and in 36 were greater than 2 cm (diffuse). Within the first group there was a prevalence of hypoechoic forms (61,9%). While isoechoic and hyperechoic foci were observed in 14.3% and 23.8%. In diffuse prostatic carcinoma, mixed echogenicity was observed in 50% of patients, hypoechoic in 27.8% and isoechoic in 22.2%. The variations in the appearance of prostatic cancer indicate that sonographic texture is related to the size and histopathologic features of the neoplastic growth.  相似文献   
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Sixteen patients with lacunar alterations of the squamous occipital bone were studied in various radiographic projections; in many cases tomography and technetium 99m bone scan studies were also performed. In 7 cases lacunae in the cerebral fossa were observed, with an average diameter of 3 cm. These defects were due to a thinning of the inner table of the theca. In 9 cases smaller lacunae were demonstrated bilaterally, which were more radiolucent, isolated or confluent, located in the area corresponding to the internal occipital protuberance at the ridges of the cruciform eminence. The latter were representative of diploic venous lakes, as best demonstrated in lateral projection. This kind of lacunae are considered as anatomic variants, because no bone destruction is demonstrable, as confirmed by technetium scintigraphy.  相似文献   
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Immunoglobulin A and G (IgA, IgG) serum concentrations were detected in children with nonallergic/intrinsic (36 children) or allergic/extrinsic asthma (43 children) and in age-matching control children (40 children). Asthmatic children with allergic asthma had lower IgA (1.36+/-0.54 g/L) and higher IgG (10.48+/-2.77 g/L) levels than the age-matching control children group (1.63+/-0.69 vs. 9.01+/-2.32 g/L). Children with nonallergic/intrinsic asthma had lower IgA (1.03+/-0.41 g/L) ( p = 0.004) and IgG (8.38+/-1.93 g/L) (p = 0.001) levels than the allergic/extrinsic asthma group (1.36+/-0.54 vs. 10.48+/-2.77 g/L). Low IgA levels were found in children with nonallergic/intrinsic asthma and high IgG levels were found in those children with allergic/extrinsic childhood asthma. The hypothesis is that the increased incidence of asthma in the population may be caused by a decrease in childhood infections (hygiene hypothesis). Frequent infections in early life boost the immune system, stimulating Th1-type response in young children and reducing the risk of atopic diseases. Our hypothesis is that low IgA (and/or IgG) levels in our patients might be responsible for infection development among those children with nonallergic/intrinsic asthma. These infections stimulate the normal development of immune system in young children, reducing risk of atopy, so that those children do not get allergic/extrinsic childhood asthma. Intrinsic childhood asthma=nonallergic (nonatopic) childhood asthma. Extrinsic childhood asthma=allergic (atopic) childhood asthma.  相似文献   
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Organization of management of the wounded and sick has been presented at the joint training of the military medical and public health services under conditions of defense of big cities in daily light, in winter, under unfavourable meteorological conditions. The aim of the training was to check organization and preparedness of all structures of General National Defense in removing consequences after the nuclear plant accident during combat for defense of a big city. General conditions of training, casualty assessment, distribution of casualties according to the spatial distribution of radiation and radioactive contamination are given. Health institutions, military medical units and institutions, and other participants in health protection as well as their tasks are reported. Protective measures which should be applied at the level of "N" nuclear plant and organization in the defense of a big city are recommended.  相似文献   
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Archival material from 47 patients with primary squamous cell carcinoma of the head and neck (SCCHN) was studied immunohistochemically for the presence of nm23-H1 protein. Our data indicate that nm23-H1 protein expression is a common event in SCCHN and that there is a trend toward correlation of increased expression of nm23-H1 with increasing tumor size (p = 0.072). The results also show that when adjusting for age and cause of death, there tended to be an inverse relationship between overall survival and the expression of nm23-H1 gene in the primary tumor (p = 0.088).  相似文献   
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