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131.
132.
LT is a practical therapeutic alternative for unresectable hepatoblastoma; however, deciding when to perform LT is difficult. The aim of this study was to optimize the timing of LT for hepatoblastoma using pretransplant trends in AFP levels. Trends in pretransplant AFP levels and their influence on post‐transplant outcomes were retrospectively evaluated. All patients who underwent living donor LT for hepatoblastoma in our institution since 2002 were included. Variables analyzed included history of prior tumor resection, pretransplant AFP responses to chemotherapy, metastatic disease at diagnosis, and post‐transplant chemotherapy. Eight patients (seven boys and one girl; median age, 35 months; range, 15 months‐12 years) were transplanted. The overall post‐transplant recurrence‐free survival rate was 62.5% (5/8) with a mean follow‐up of 77 months. Patients with post‐transplant recurrence showed a 0.573 log increase in AFP levels after the last chemotherapy session before LT. This was significantly higher than the 0.279 log decrease observed in patients without post‐transplant recurrence (= .024). Because the AFP response cannot be accurately predicted before each cycle of chemotherapy, it may be appropriate to perform LT when AFP levels do not decrease after the last cycle and before they are found to be elevated again.  相似文献   
133.
Non-African Burkitt's lymphoma is presented in a 29-year-old, unmarried woman, who developed tumors in both breasts and ovaries, ascites and pleural effusion. Assessment of B cells in the tumor cells, derived from ascites, pleural effusion and tumor tissue is 90%, surface IgM being consisted of 86%, in an average. Histologically, the tumor tissue demonstrates prominent, so-called starry-sky effect, and cytologically, tumor cells are poorly-differentiated lymphocytoid ceUs in their features.  相似文献   
134.
135.
Nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3), members of the neurotrophin family, bind to and activate TrkA, TrkB and TrkC, respectively, members of the Trk receptor tyrosine kinase family, to exert various effects including promotion of differentiation and survival, and regulation of synaptic plasticity in neuronal cells. Many reports have suggested that different neurotrophins show distinct biological functions, although molecular mechanisms by which neurotrophins exert their different functions remain unclear. In the present study, we found distinct usages of phospholipase Cgamma (PLCgamma) and Shc in intracellular signaling stimulated by neurotrophins. BDNF stimulated much stronger interactions of PLCgamma with Trk than NGF and NT-3 in PC12 cells stably expressing TrkB and cultured cerebral cortical neurons, respectively, although BDNF, NGF and NT-3 induced similar levels of tyrosine phosphorylation of Trk. Furthermore, the cultured cortical neurons showed large PLCgamma-dependent increases in intracellular Ca(2+) levels in response to BDNF compared with NT-3. In Shc signaling, NGF, but not BDNF, displayed interactions between Trk and Shc in a phenylarsine oxide (PAO; an inhibitor of tyrosine phosphatase)-dependent manner in TrkB-expressing PC12 cells. These results indicated that neurotrophins stimulate distinct kinds of interactions between Trk and PLCgamma and between Trk and Shc. These differences may lead to the distinct biological functions of neurotrophins.  相似文献   
136.
We report a 52-year-old Japanese woman who developed dyskinesia, epilepsy, and gait disturbance. She was well until 35 years of age, when she noted the onset of gait disturbance. She also noted abnormal involuntary movements in her limbs. She also noted dysarthria at age 38. A neurologist examined her at age 41. The neurologist found cerebellar ataxia and dyskinesia. The atrophy of the brain stem and the cerebellum was on CT. She started to have generalized convulsion with loss of consciousness. Dementia became apparent at age 40. In October, 1993, she became psychotic in which she behaved violently taking off her clothes shouting as "Fire". She was treated with major tranquilizers and became quiet. However, choreic movements became prominent. Her subsequent course was complicated with dysphagia, dementia, convulsion, and frequent bouts of pneumonia. She expired on January 24, 2000 after developing pneumonia. Her father and one sibling had similar motor disturbances. She was discussed in a neurological CPC. The chief discussant arrived at conclusion that the patient had dentatorubral-pallidoluysian atrophy. Most of the participants agreed with this diagnosis. Postmortem examination revealed that entire brain looked smaller than normal including the brain stem and the cerebellum. The cerebellar dentate nucleus showed loss of neurons and gliosis; glumose degenerations were also seen. The external segment of the pallidum showed neuronal loss and gliosis. The subthalamic nucleus showed gliosis without neuronal loss. A demyelinated focus was found in the pons; the lesion looked similar to central pontine myelinolysis. The cerebral white matters were unremarkable. Other areas were unremarkable. The pathological diagnosis was dentatorubral-pallidoluysian atrophy. The pathologic lesion which might explain her dementia was not apparent.  相似文献   
137.
The present study examines the effects of long-term electrical stimulation of the auditory nerve on the morphology of neurons in the cochlear nucleus in young, sensorineural deaf animals. Kittens, systemically deafened using kanamycin and ethacrynic acid, received bilateral cochlear implants and were stimulated unilaterally for periods of up to four months. After sacrifice, cross-sectional areas of neuron somata were measured with an image-analysis system and compared using nonparametric statistics. The areas of cell somata within the anteroventral cochlear nucleus (AVCN) on the stimulated side were significantly larger than those of corresponding somata on the control, unstimulated side (P less than 0.001). However, there was no statistically significant difference among dorsal cochlear nucleus (DCN) neurons. These results indicate that long-term electrical stimulation of the auditory nerve can at least partially negate some effects of early postnatal auditory deprivation at the level of the cochlear nucleus.  相似文献   
138.
Acute mediastinal hemorrhage is rarely caused by a rupture of mediastinal neoplasms. We herein report a 70-year-old man who presented with mediastinal parathyroid adenoma manifested by the sudden onset of mediastinal bleeding. Preoperatively, he showed no symptoms or complications associated with hypercalcemia. No particular findings were found in the thorax except for a small nodule in the upper mediastinum. The nodule was resected through a collar incision, and pathohistology showed a parathyroid adenoma, with an intracapsular hemorrhage. Received: July 17, 2001 / Accepted: March 5, 2002  相似文献   
139.
We report herein a rare case of a functional mediastinal parathyroid cyst. A mediastinal tumor was detected by a chest X-ray film and subsequent computed tomography (CT) scan in a 68-year-old woman who was asymptomatic. Biochemical examination revealed that her serum calcium and intact-parathyroid hormone (i-PTH) levels were above the normal range. The findings of chest CT and magnetic resonance imaging suggested a cystic mass. The mass, which adhered tightly to its surrounding structures, was resected through a median sternotomy. The patient had an uneventful postoperative course, and her serum calcium and i-PTH levels rapidly returned to within the normal range. Received: March 21, 2001 / Accepted: September 11, 2001  相似文献   
140.
Six newborn infants with intrauterine supraventricular tachyarrhythmias (five cases of atrial flutter and one of supraventricular tachycardia) are described. Transplacental digitalisation was attempted in three cases. Supraventricular tachycardia associated with hydrops fetalis, detected in a fetus at a gestation of 31 weeks, was successfully converted to normal sinus rhythm eight days after the mother began treatment with digoxin. The serum concentration of digoxin in cord blood almost equalled the maternal concentration in three cases. In the remaining three cases treatment with digitalis was effective in converting tachyarrhythmias to sinus rhythm after delivery. With maintenance digoxin therapy, the prognosis of fetal tachyarrhythmias seems to be good, once conversion to sinus rhythm has been accomplished.  相似文献   
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