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51.
Langerhans cell histiocytosis is currently regarded as a reactive proliferative process of Langerhans cells rather than a malignancy. The disease is characterized by Langerhans cell infiltration of skin, lung, bone and other organs. We report a 74-year-old man with Langerhans cell histiocytosis who had generalized hemorrhagic and crusted papules. He also had diabetes insipidus. Because he did not have any severe constitutional symptoms or failure of vital organs, we applied topical PUVA treatment to his skin lesions, which responded well to the therapy. Diabetes insipidus, however, remained, in spite of X ray radiotherapy for the pituiary lesion.  相似文献   
52.
AE0047, a novel calcium antagonist, has mild and long-acting hypotensive effects. This drug also has more selective dilating action on cerebral arteries than on other systemic ones. We studied the cerebral vasodilatative effects of AE0047 by means of vertebral angiography in anesthetized dogs. Vertebral blood flow (VBF) was significantly increased by 91, 139 and 132% in 10, 30 and 60 min after intravenous administration of AE0047 at 30 micrograms/kg, respectively. No difference in vasodilating action was observed among basilar, posterior communicating, middle cerebral and internal carotid arteries. In basilar artery, the dilatative rate was about 30% between 10 and 60 min after injection of AE0047. Following intravertebral administration of endothelin at 100 pmol/kg, small vessels of the cerebral artery were constricted, and VBF was gradually decreased. AE0047 eliminated the vasoconstriction and increased VBF. Moreover, the vasoconstrictive effect of endothelin was prevented by pre-treatment of AE0047. These results indicate that AE0047 has potent vasodilating and spasmolytic actions on cerebral arteries.  相似文献   
53.
There have only been a few studies of chemo-endocrine therapy compared with endocrine therapy alone in newly diagnosed prostate cancer patients. We assessed the effects of these two therapies by comparing long-term survival rates. One hundred and twenty-nine patients were entered in this study between November 1977 and March 1992. Seventy-seven patients were treated with endocrine therapy alone. Other 52 patients received chemo-endocrine therapy, which included orchiectomy and/or diethylstilbestrol diphosphate (DES-DP) plus Cisplatin, with or without other cytotoxic agents. All patients had bone metastasis at the beginning of the study. There was a significant difference in survival between patients who received endocrine therapy and chemo-endocrine therapy (P = 0.0078). That is, survival rate was superior for the chemoendocrine therapy patients throughout the entire follow-up period. These data suggest that early chemo-endocrine therapy containing Cisplatin, with or without maintenance chemotherapy, is a potentially effective treatment for newly diagnosed metastatic prostate cancer and is worth further investigation via a randomized trial.  相似文献   
54.
We present the fourth known case of endometrial carcinoma, and the second case of endometrial small-cell carcinoma, to be associated with paraneoplastic retinopathy. Initial symptoms were decreased visual acuity and a narrowing of the visual field. Endometrial carcinoma was diagnosed several months later. An antibody to 34-kDa bovine retinal antigen was detected in the patient's serum. Thus, autoimmunity was suspected as the cause of the retinopathy. In patients with endometrial carcinoma with visual disturbance of unknown cause, paraneoplastic retinopathy should be suspected.  相似文献   
55.
The effects of three calmodulin antagonists on rat parotid amylase release were investigated in vitro using a dispersed acinar cell preparation. The potent calmodulin antagonists, trifluoperazine (TFP) and N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide (W-7), inhibited both 1 microM isoproterenol (ISO)- and 1 mM dibutyryl cyclic AMP (DBcAMP)-stimulated amylase release in a dose-dependent manner at concentrations of 25-100 microM. The IC50 values for the ISO-stimulated amylase release were 22 microM with TFP and 42 microM with W-7, and the values for the DBcAMP-stimulated release were 25 microM and 48 microM, respectively. The weak calmodulin antagonist, N-(6-aminohexyl)-1-naphthalenesulfonamide (W-5), caused only slight inhibition at a concentration of 100 microM. These calmodulin antagonists only had a very small effect on the spontaneous release of lactate dehydrogenase. The results suggest that the calcium-calmodulin system may play a role in the exocytotic process of amylase release from the rat parotid gland.  相似文献   
56.
The problem of mixed H2/H control with pole placement is considered for linear time-invariant systems. This is the problem of determining a controller for linear time-invariant systems which minimizes the H2-norm of a certain closed-loop transfor function subject to an H-norm constraint on another closed-loop transfer function and an additional constraint on the location of the closed-loop poles in the complex plane. An optimization problem is posed for the pole-constrained H2/H, problem in such a way that the objective function is expressed as a weighted sum of the actual H2 cost and its upper bound. A necessary condition for the optimization problem is derived via the Lagrange multiplier technique. The condition involves a set of highly coupled equations. By sacrificing the H2 performance, an alternative optimization problem is posed in order to simplify the necessary condition. An iterative algorithm for solving the coupled equations arising in the necessary conditions is proposed and numerical examples are presented.  相似文献   
57.
A 36 year old woman was admitted to our department because of a chest X-ray which showed multiple developing shadows. She underwent bilateral exploratory thoracotomies and a total 5 tumors were resected and pathologically diagnosed as benign metastasizing leiomyoma, the largest of which was positive for the progesterone receptor and negative for the estrogen receptor. A histogram of this tumor using a flow cytometer showed a diploid pattern and 4.6 percent of the S phase which was not more than that of a leiomyoma of the uterus from another patient. Two months later, she underwent a hysterectomy and bilateral salpingo-oophorectomy for treatment of the positive progesterone receptor in the pulmonary lesions. The resected uterine myoma and normal myometrium showed positive estrogen and progesterone receptors. For the subsequent 28 months she has been free of any further symptoms. Benign metastasizing leiomyoma of the uterus is a rare disease and very interesting because of its histological benignity and hormonal dependency. However, according to the literature, it is often confused in entity due to the fact that normal lung tissue also possesses hormone receptors. Considering our data on hormone receptors, it is rational to think that multiple leiomyomatous lesions in the lung should only be diagnosed as benign metastasizing leiomyomas when they possess positive estrogen and progesterone receptors.  相似文献   
58.
Central venous catheterization for pressure monitoring and drug administration is often important in the anesthetic management of infants undergoing cardiovascular surgery. We examined the effects of patient age, weight, and central venous pressure and the experience of the anesthesiologist on the rate of successful catheterization and catheterization time of the internal jugular vein (IJV) in a prospective study. We studied 106 infants undergoing IJV catheterization for cardiovascular surgery over a 7-mo period at our institution. We catheterized the IJV by the high approach. The direct venipuncture or the Seldinger method was used according to the patient's weight. Overall successful catheterization rate was 97.2%, and the average catheterization time was 353 +/- 21 s (mean +/- SEM). Complications included arterial puncture in 12 cases (11.3%), hematoma formation in four cases (3.8%), and catheter malposition in two cases (1.9%), but pneumothorax was not observed. When a patient was younger than 3 mo or weighed less than 4.0 kg, successful catheterization rate decreased significantly to 81.3% and 78.6%, respectively. Catheterization time was inversely correlated with both age and weight, whereas central venous pressure did not affect either successful catheterization rate or catheterization time. We were unable to demonstrate that the experience of the anesthesiologist plays a significant role in the success or complication of the catheterization procedure. Our results indicate that IJV catheterization by the high approach is a reliable and useful technique in infants, and that the weight and age of the patient significantly influence the rate of successful catheterization.  相似文献   
59.
In order to assess the accuracy of electroencephalography (EEG), in children who have undergone cardiac surgery under simple deep hypothermia, the relation between IQ or schoolwork achievement and the duration of circulatory arrest was investigated in 75 such children. Abnormal preoperative EEG's were found in 16 per cent of the children while abnormal postoperative EEG's were found in 17 per cent. The children were divided into 4 groups, according to pre- and postoperative EEG results. Schoolwork achievement scores ranged between 3.0 and 3.2, the difference among the groups being insignificant. Moreover, no significant shift in IQ was found among the groups. Finally, regarding the number of children who were able to go on to a higher level of education, including high school the college or university, again no significant differences were found among the 4 groups. In a comparison with the number of such children in neighboring Nagasaki prefecture able to continue on to a higher level of education, no significant differences were seen either. The findings and statistics of this investigation therefore indicate that pre- and postoperative EEG's are not always a reliable reference for assessing the prognosis of cerebral activity.  相似文献   
60.
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