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Sonoelasticity imaging of prostate cancer: in vitro results   总被引:2,自引:0,他引:2  
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Nerve growth factor (NGF), its messenger RNA (mRNA) and its receptor protein and mRNA are found in several brain regions. Little attention has been given to the possibility that the hypothalamus, which controls the endocrine system, may produce NGF and/or express NGF receptors. This would indicate the existence in this brain area of neuronal populations which are either target for NGF-responsive cells or sensitive to NGF, respectively. Blot hybridization of polyadenylated (poly(A)+) RNA to a mouse NGF cRNA probe revealed the presence of NGF mRNA in both the suprachiasmatic region (henceforth, called preoptic area [POA]) and medial basal hypothalamus (MBH) of developing female rats. The mRNA was already detectable on fetal day 18 and reached maximal levels around postnatal day 3 (MBH) and 12 (POA), declining thereafter. This pattern was temporally different than that of areas known to produce NGF, i.e., the neocortex (Cc) and hippocampus (Hc). In agreement with previous reports, NGF mRNA levels in these areas were negligible before birth, became maximal between the second and third week of postnatal life and decreased moderately thereafter. The concentration of NGF protein, measured by a two-site enzyme immunoassay, was 3 times higher in the POA than in the MBH at an infantile age (day 12), increasing 2-fold in the POA of juvenile animals (day 28) but not in the MBH. This developmental pattern was similar to that seen in the Hc, though the NGF concentrations were significantly lower in the POA.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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IL2-PE40 is a chimeric protein composed of human interleukin-2 (IL2) genetically fused to a modified form of Pseudomonas exotoxin lacking the cell recognition domain. IL2-PE40 is cytotoxic for IL2 receptor-bearing lymphocytes in culture and can inhibit activation of T cells in vivo. IL2-PE40 can significantly diminish antigen-stimulated proliferation of lymphocytes sensitized to myelin basic protein. Intraperitoneal administration of IL2-PE40 not only markedly inhibits the clinical manifestations of adoptively transferred relapsing experimental allergic encephalomyelitis but also dramatically reduces both inflammation and demyelination characteristic of the disease.  相似文献   
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C P Caygill  M J Hill  C N Hall  J S Kirkham    T C Northfield 《Gut》1987,28(8):924-928
Of 5018 patients who had undergone gastric surgery at St James Hospital, Balham, at least 25 years ago, death certificates have been received for 2768, whilst 1746 patients are still alive and are flagged (Office of Populations, Censuses and Surveys (OPCS) will notify us of their death and its cause) and only 504 could not be traced. Mortality from cancers of various organs has been determined using a 'years at risk' calculation in five year bands. There was no increase in mortality risk from any cancers during the first 15 postoperative years, but from 20 years after operation there was a significant excess risk not only of cancer of the stomach (4.5-fold), but also of the large bowel (1.6-fold), bronchus (3.9-fold), pancreas (4.0-fold), biliary tract (9.1-fold), oesophagus (2.3-fold), bladder (2.4-fold), breast (4.0-fold), and cancer of all sites (3.3-fold). These findings are consistent with the production in the operated-upon stomach of circulating carcinogens with a 20 year latency period.  相似文献   
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Incestuous child sexual abuse has received increasing attention recently, but relatively little attention has focused on the multigenerational dimensions of this problem. The case presented places incest into a multigenerational context and demonstrates how quickly family relationships may become eroticized in an uncommon form: between sisters.  相似文献   
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While much time has been spent deliberating about the definition of play, little emphasis has been placed on what children themselves perceive as play. The aim of the present study was to examine social context as a cue for children's perceptions of play and learning. Ninety-two children aged between four and six years (mean four years nine months) participated in the study and completed the Activity Apperception Story Procedure. Children were asked to sort photographic stimuli into those they believed depicted play/not play and learning/not learning. Each of the stimuli were identified by independent raters as containing one of the following social cues; teacher absence (solitary activity, parallel activity or cooperative activity) or teacher presence (teacher involved activity or teacher directed activity). Findings revealed that children associated teacher absence with play. More specifically, children made links between play and the presence of peers (parallel and cooperative activity). Findings are discussed in relation to play in the early years curriculum, differences in children's early educational experiences and the importance of understanding children's perceptions of play.  相似文献   
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