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971.
Background:  Apocrine carcinomas are rare, the immunohistochemical characterizations that are incomplete. The purpose of this study was to determine the immunohistochemical characteristics of mucin core proteins and keratins in apocrine carcinoma, extramammary Paget's disease (EMPD) and apocrine nevus.
Methods:  We report four cases of apocrine carcinomas along with immunohistochemical analyses: (i) an axillary apocrine carcinoma with an apocrine nevus, (ii) an inguinal apocrine carcinoma, (iii) a vulvar apocrine carcinoma with EMPD and (iv) an axillary apocrine carcinoma with EMPD and an apocrine nevus.
Results:  The tumor cells of apocrine carcinomas, EMPD and apocrine nevi displayed a positive reaction to MUC-1 and CK7 and a negative reaction to CK20. Apocrine carcinomas had high molecular weight (HMW) cytokeratin(+)/CK5(+)/CK14(−)/MUC5AC(−), EMPD with underlying apocrine carcinoma had HMW cytokeratin(−)/CK5(−)/CK14(−)/MUCA5AC(−) and the apocrine nevi had HMW cytokeratin(+)/CK5(+)/CK14(+)/MUCA5AC(+).
Conclusion:  The immunohistochemical findings suggest that apocrine carcinomas, apocrine nevi and EMPD with underlying apocrine carcinomas are quite different, even though they are all derived from apocrine glands.  相似文献   
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Neuron-specific γ-enolase in human neurogenic tumors, including gliomas, transplanted gliomas, and permanent human glioma cell lines, was studied quantitatively, using newly established enzyme immunoassay methods, together with immunostaining of the tissue and cell preparations. A significantly high level of γ-enolase was found in some glioblastomas, astrocytomas and oligodendrogliomas as well as medulloblastomas. Glioblastomas transplanted into mice and cultured cell lines derived from the same origins, as well as the permanent human glioma cell lines, also contained γ-enolase, although the contents were low compared with findings in the original tumor tissues. Immunohistochemically, γ-enolase stained intensely in the glioblastomatous cells. Serum γ-enolase concentrations in some patients with gliomas and those of all the transplanted mice were enhanced. The serum γ-enolase levels in the mice correlated well with size of the transplanted tumor tissues. These results indicate that neuron-specific γ-enolase is produced in some neurogenic tumors of nonneuronal origin, therefore, serum γ-enolase may be a useful biomarker for monitoring the extent of disease in patients with gliomas.  相似文献   
976.
This study characterizes the physiological features and limitations of K(+)-free dialysis to detect changes in extracellular concentration of K+ ([K+]e) in the rat hippocampus in vivo. It also demonstrates the effects of Ca(2+)-free perfusate containing Co2+ or Mg2+, which blocks Ca2+ entry into the presynaptic nerve terminal, on the abrupt increase in [K+]e detected by this technique during cerebral ischemia. K(+)-free dialysis for 40 min caused no significant changes in the baseline [K+]e. In contrast, Ca(2+)-free dialysis for 40 min significantly reduced the extracellular Ca2+ concentration. Under this condition, together with addition of Co2+ or Mg2+ to the perfusate, the increase in [K+]e was delayed, and a delay in reaching the maximum level was observed in a dose-dependent manner. These results are consistent with the hypothesis that the initial increase in [K+]e during cerebral ischemia is related to the Ca(2+)-dependent exocytotic release of neurotransmitters from depolarized nerve terminals.  相似文献   
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To assess the roles of substance P in neurologic or psychiatric illnesses, effects of acute or chronic (40- or 80-day dietary) treatment with trihexyphenidyl and carbamazepine alone or in combination with haloperidol on substance P content were investigated in the rat brain. Either acute or chronic trihexyphenidyl administration did not alter substance P content when administered alone and did not prevent the haloperidol-induced substance P decrease in the striatum and substantia nigra when coadministered with haloperidol. Chronic dietary carbamazepine administration dose-dependently increased substance P content in the striatum and substantia nigra, but not in the raphe area, in a haloperidol-reversible manner. Carbamazepine also dose-dependently increased gamma-aminobutyric acid levels in the substantia nigra without altering the striatal dopamine turnover rate. The lack of effect of trihexyphenidyl, an anticholinergic drug used to treat antipsychotic drug-induced extrapyramidal (Parkinson) syndromes, suggests that antipsychotic drug-induced reduction in substance P content is not involved in the extrapyramidal side effects. Since the effects of carbamazepine on substance P content are identical with previously described effects of lithium, an alteration in substance P neurotransmission may be one of the neurochemical bases of common clinical and behavioral effects of carbamazepine and lithium on affective disorders.  相似文献   
980.
A 48-year-old slender woman presented with a rare case of spontaneous intracranial hypotension syndrome manifesting as patulous Eustachian tube. The patient complained of sudden onset of ear fullness and nasal voice as well as typical orthostatic headache. Patulous Eustachian tube was identified by observation of synchronous movement of the tympanic membrane with respiration and swallowing. The diagnosis of spontaneous intracranial hypotension was confirmed by negative cerebrospinal fluid pressure, and typical magnetic resonance imaging and radioisotope cisternography findings. All symptoms completely resolved within a few days after epidural blood patch treatment. Changes in the venous blood distribution led by collapse of the dural sac of the cervical spine in the standing position presumably caused decreased size of the pterygoid venous plexus around the Eustachian tube.  相似文献   
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