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Mouse polyclonal antisera were raised to the Mr 130,000 and Mr 115,000 cell surface glycoproteins, desmocollins, of desmosomes from bovine nasal epithelium. Immunoblotting confirmed that the antisera were specific for the desmocollins. An immunofluorescence study showed that the antisera distinguished between the basal and suprabasal layers of bovine and human epidermis. The antibodies reacted with cultured keratinocytes only after calcium-induced stratification. In epidermis, therefore, there appears to be a difference between the desmocollins of basal and suprabasal cells that may be important in relation to epidermal differentiation. Previous work has shown that polyclonal antisera raised in other animals (guinea pigs and rabbits) against desmocollins, as well as against other desmosomal components, react with all desmosome-containing epithelia. In contrast, an immunofluorescence survey of bovine, rat, and human tissues showed that the present mouse antisera stained only suprabasal skin cells and the arachnoid layer of the meninges, demonstrating that these have common determinants that distinguished their desmocollins from those of all other tissues. The antibodies also stained 11 of 12 meningiomas and, therefore, may be useful as a marker not only for the diagnosis of these tumors but also for investigation of their histogenesis.  相似文献   
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Children with pure depression or depression plus an anxiety-related disorder (n = 14) had a higher drug response rate (57%) and a lower placebo response rate (20%) when compared to children with depression plus a concomitant conduct or oppositional disorder (n = 17) (33% drug response rate and 67% placebo response rate). These findings could explain why studies of prepubertal-onset depression found no differences between drug and placebo treatment assuming that a large percentage of the studies' subjects had concomitant conduct or oppositional disorders. The children with pure depression or depression plus an anxiety-related disorder had different symptom clusters from those with depression plus a concomitant conduct or oppositional disorder. The former had more severe CDRS ratings on sleep, appetite disturbance, depressed feelings, and psychomotor retardation. In contrast, those with a concomitant conduct or oppositional disorder had shorter attention spans and were more likely to disturb other children (based on Conners scale scores).  相似文献   
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Summary Single-chain toxin was investigated in vitro and in vivo for limited proteolysis into the fully active two-chain toxin. Plasmin from serum, elastase and gelatinase from leucocytes, as well as clostripain from C. histolyticum cleaved single-chain toxin and increased by that way its ability to inhibit [3H]noradrenaline release in vitro. Cultured mouse brain generated fragments from 125I-single-chain toxin which were cell-associated. Some of them comigrated in electrophoresis with light and heavy chain after mercaptolysis. When injected i. v. into rats, 125I-single-chain-toxin disappeared from the blood with a half-life of about 11 h without signs of nicking. However, after its injection into the triceps surae muscle both single- and two-chain toxin were found in the ipsilateral ventral horn of the spinal cord. Thus single-chain toxin is subjected to limited proteolysis by enzymes involved in tissue damage, by cultured brain tissue, and during or after its retrograde axonal transport to the spinal cord. Limited proteolysis is necessary for the release of the light chain known to mediate the action of toxin on several systems.  相似文献   
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The exact regional correlation of findings of facial bone scans, planar or SPECT, to dental orthopan X-ray films (OPT) is difficult because of the very different projection techniques. To improve correlative imaging in this regard a projection algorithm was developed that uses SPECT data of the skull for reconstructing an orthopan tomoscintigraphic projection. Fourteen conventional SPECT slices of the upper and lower jaws were obtained during bone scanning. All mandibular slices were superimposed resulting in a horseshoe shaped structure, which was marked by an ROI which was divided into segments. All 14 SPECT slices were then masked by this segmental ROI, thereby marking the teeth-carrying bone in all slices. The information from this horseshoe like ROI is then transformed into lines. Line by line arrangement results in an orthopan projection, the orthopan tomoscintigram. This new display allows 1:1 true scale superimposition with the X-ray OPT and markedly facilitates correlative imaging.  相似文献   
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