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11.
A 28-year-old man complaining of myiodesopsia was given a diagnosis of uveitis. Subsequently he complained facial nerve palsy and enlargement of parotid gland. Heerfordt's syndrome was diagnosed based on the results of several examinations. Facial nerve palsy, enlargement of the parotid gland and uveitis were improved by systemic corticosteroid therapy. At present he is receiving systemic corticosteroid therapy, but numbness in the mouth, thought to be the involvement of the trigeminal nerve, remains. Systemic corticosteroid therapy is usually effective for most cases with Heerford's syndrome. On the other hand, there are some cases with the prolonged peripheral nerve involvement despite systemic corticosteroid therapy, as seen in this case. If peripheral nerve involvement is prolonged, it is necessary to consider small-fibre neuropathy as one possible cause.  相似文献   
12.
The correlation between the extent of peritumoral edema and the proliferative potential or the infiltration of mononuclear cells was studied in 17 gliomas. The peritumoral edema was evaluated on contrast enhanced CT scan as the ratio of the low density area around the tumor to the enhanced high density area. The proliferative potential and the infiltration of mononuclear cells into the tumor were investigated immunohistochemically using monoclonal antibody (MAb) against DNA polymerase alpha and anti-Leu MAb's respectively. There was a significant correlation between the extent of the peritumoral edema and the percentage of DNA polymerase alpha positive cells. The degree of the infiltration of mononuclear cells into the tumor tissue also correlated with the extent of peritumoral edema. In gliomas with high proliferative potential and/or severe infiltration of mononuclear cells, the peritumoral edema may be aggravated by disruption of the blood-brain-barrier and increased vascular permeability.  相似文献   
13.
A case of thrombasthenia (Glanzmann) associated with an intracerebral cavernous angioma in a 32-year-old woman is reported. Since her childhood, the patient had experienced a tendency to develop purpura following minor trauma. But she had not had major bleeding even during pregnancy and delivery. On April 4, 1987, she presented generalized convulsion. A high density mass in the right temporal lobe was demonstrated with CT scan. Carotid angiogram was normal except that the right anterior choroidal artery was stretched. Inhomogeneous signal intensities in T1- and T2-weighted MRI images were seen in the tumor locus. The clinical diagnosis was cavernous angioma which was complicated with intracerebral hemorrhage. The patient had a disorder of platelet function without thrombocytopenia. Her bleeding time was markedly prolonged. Because of this, we did not try surgical excision at first. During the 13-month observation period, however, intracerebral bleeding occurred 5 times. We decided to operate on the patient using fresh blood and platelet transfusion. The postoperative course was uneventful and pathological diagnosis confirmed cavernous angioma. We would like to emphasize possible pitfalls in treating cases of intracerebral angioma with thrombasthenia.  相似文献   
14.
We describe our experience with a patient in whom a traumatic right diaphragmatic hernia developed 4 years after sustaining injury and review cases of delayed diaphragmatic injury reported in Japan. The patient was a 28-year-old man who sustained a severe contusion of the right epigastric region and fractured a right rib in a traffic accident in September 1992. In August 1996, the patient presented with shortness of breath on effort or after meals. A chest roentgenogram revealed intestinal gas in the right side of the thoracic cavity. A right diaphragmatic hernia was diagnosed on the basis of a gastrointestinal series, and the patient was operated on. The hernial orifice extended anteriorly from the central tendon in an 11:00 direction and measured 11 x 6 cm. The small intestine, right side of the colon, and liver were herniated. A total of 297 cases of blunt traumatic diaphragmatic hernia were reported in Japan between 1981 and 1996, including 47 cases (left side, 32 cases; right side, 15 cases) of delayed diaphragmatic hernia, defined as occurring one month or more after injury. Diaphragmatic hernia should be considered as a possible diagnosis in patients with abnormal shadows in the thoracic region who have recently sustained injury or who have a past history of injury.  相似文献   
15.
It has been recently reported that acute immobilization stress almost completely suppresses the luteinizing hormone (LH) release induced by naloxone, a μ-opioid antagonist, in ovariectomized estrogen-primed rats. The present study examined the possible involvement of the pineal gland in the acute immobilization-related suppression of the naloxone-induced LH release. An intraventricular (ICV) injection of 15 μg naloxone produced an abrupt increase in circulating LH concentrations in non-stressed rats. The naloxone-induced LH release was completely eliminated when tested 60 min after the end of a 30 min session of acute immobilization. The same stress conditions did not affect LH-releasing hormone (LHRH)-induced LH release, suggesting that the stress-related suppression of the naloxone-induced LH release was a suprapituitary event. In chronically-pinealectomized rats, but not in sham-pinealectomized rats, naloxone injected 60 min after the end of the stress session evoked a significant increase in serum LH concentrations. However, naloxone injected ICV during the acute immobilization did not elicit LH release in either pinealectomized or sham-operated rats. Under non-stressed conditions, the LH secretory response to naloxone was similar in pinealectomized and sham-operated animals. The same stress (30 min immobilization) significantly increased pineal melatonin content as well as plasma melatonin concentrations in rats bearing intact pineal glands, indicating that stress actually affected the pineal function. These results provide evidence for a role of the pineal in the suppression of the LH response to naloxone after stress, but not during stress.  相似文献   
16.
The gene Bcl11b, which encodes zinc finger proteins, and its paralog, Bcl11a, are associated with immune-system malignancies. We have generated Bcl11b-deficient mice that show a block at the CD4-CD8- double-negative stage of thymocyte development without any impairment in cells of B- or gammadelta T cell lineages. The Bcl11b-/- thymocytes showed unsuccessful recombination of V(beta) to D(beta) and lacked the pre-T cell receptor (TCR) complex on the cell surface, owing to the absence of Tcrb mRNA expression. In addition, we saw profound apoptosis in the thymus of neonatal Bcl11b-/- mice. These results suggest that Bcl11b is a key regulator of both differentiation and survival during thymocyte development.  相似文献   
17.
OBJECTIVE: Saliva secretion is mediated by cAMP and the calcium signaling pathway in salivary acinar cells. The PKA signaling pathway plays an important role in protein secretion through the activation of cAMP, in fluid secretion through the elevation of intracellular calcium and in the activation of cAMP response element-binding protein (CREB), which is involved in these signaling cascades. In this study, we investigated whether the activation of CREB plays a part in the salivary secretion in mice. METHODS: We examined CREB activation by assessing phosphorylation at the serine-133 position using Western blotting. RESULTS: Carbachol (a muscarinic acetylcholine agonist) and isoproterenol (a beta-adrenergic agonist) markedly activated CREB in parotid acinar cells. Carbachol and isoproterenol-induced CREB phosphorylation was blocked by atropine (a muscarinic acetylcholine antagonist) and propranolol (a beta-adrenergic antagonist), respectively. The PKA inhibitor H89 inhibited CREB activation, but the PLC inhibitor U73122 did not. Moreover, carbachol- and isoproterenol-stimulated amylase secretion from parotid acinar cells was inhibited by H89 and adenoviral dominant-negative CREB. CONCLUSION: These results indicate that the muscarinic and beta-adrenergic activation of CREB was mediated through the PKA pathway and that CREB is involved in protein secretion from parotid acinar cells.  相似文献   
18.
An ultrastructural analysis of oral balloon cell nevus of intramucosal type complemented with an immunohistochemical study was performed for the first time. The lesion was composed of large balloon cells with an admixture of small nevus cells and melanophages at the periphery. Balloon cells showed cytoplasmic accumulation of vacuoles of varying sizes and the presence of microgranular and vacuolated melanosomes were found. Residual cytoplasm contained no identifiable organelles. A spectrum of transitional forms between balloon cells and conventional nevus cells with microvacuoles was readily observed. Both cells exhibited intense immunoreactivity to multiple melanocytic markers. Ballooning phenomenon was not evident in melanophages containing a large amount of melanosome complex. It can be inferred, from the present and previous observations, that progressive vacuolization of melanosomes in nevomelanocytes may be responsible for the formation of peculiar ballooning appearance, suggesting an aberrant melanogenesis.  相似文献   
19.
Mice deficient in the plasminogen activator inhibitor-1 gene (PAI-1-/- mice) are relatively protected from developing pulmonary fibrosis from bleomycin administration. We hypothesized that one of the protective mechanisms may be the ability of the plasminogen system to enhance hepatocyte growth factor (HGF) effects, which have been reported to be anti-fibrotic in the lung. HGF is known to be sequestered in tissues by binding to extracellular matrix components. Following bleomycin administration, we found that HGF protein levels were higher in bronchoalveolar lavage fluid from PAI-1-/- mice compared to wild-type (PAI-1+/+) mice. This increase could be suppressed by administering tranexamic acid, which inhibits plasmin activity. Conversely, intratracheal instillation of urokinase into bleomycin-injured PAI-1+/+ mice to activate plasminogen caused a significant increase in HGF within bronchoalveolar lavage and caused less collagen accumulation in the lungs. Administration of an anti-HGF neutralizing antibody markedly increased collagen accumulation in the lungs of bleomycin-injured PAI-1-/- mice. These results support the hypothesis that increasing the availability of HGF, possibly by enhancing its release from extracellular matrix by a plasmin-dependent mechanism, is an important means by which activation of the plasminogen system can limit pulmonary fibrosis.  相似文献   
20.
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