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91.
92.
A severe case of Vogt-Koyanagi-Haradi's disease was treated with a combination therapy of cyclosporin A and steroid. The therapy was successful and showed no side effects.  相似文献   
93.
We have shown previously that activin A increases the number of immunoreactive follicle-stimulating hormone (FSH) cells. To further investigate the action of activin A, we examined its effects on anterior pituitary cells fractionated by centrifugal elutriation. Before activin A treatment, FSH cells were widely distributed among various fractions; a higher proportion of FSH cells was found in larger cell fractions (fractions 5-9), and a lower proportion in smaller cell fractions (fractions 2-4). After culture of the cells in each fraction with activin A (10 ng/ml) for 72 h, the number of FSH cells in fraction 4 only was significantly (P less than 0.05) higher by 225% than that in cells cultured without activin A. The amount of FSH secreted into the medium was minimal or undetectable in fractions 1-4. However, FSH secretion tended to be, or was significantly (P less than 0.01 in fraction 9), stimulated by activin A in fractions 5-9, in which the numbers of FSH cells were not significantly affected. These results suggest a dual mode of action of activin A on FSH: activin A increases the number of FSH cells in a specific type(s) of middle-sized cell fraction, and stimulates FSH secretion at least from larger cells without affecting the number of FSH cells.  相似文献   
94.
Magnetic resonance cholangiopancreatography (MRCP) was performed in 35 patients to evaluate the feasibility of its use as a postsurgical imaging technique after resection of the pancreas. The surgical procedures performed were: pancreatoduodenectomy in 22 patients, segmental pancreatectomy in 1, distal pancreatectomy in 7, and pyroluspreserving pancreatoduodenectomy in 5. The pancreatic duct was shown in its entirety in 24 of the 35 patients (68.6%) and was partially visualized in 8 patients (22.9%), but the intrahepatic and extrahepatic bile ducts were visualized completely in all patients. Furthermore, MRCP was able to demonstrate lesions in 3 of 6 patients who had shown clinical evidence of recurrence. The visualization of the pancreatic and bile duct system was satisfactory despite anatomical changes brought about by resection of the pancreas. Thus, we conclude that MRCP is an appropriate follow-up screening test for patients with suspected abnormalities of the biliary and pancreatic duct system.  相似文献   
95.
We reviewed 12 cases of infarcts in the territory of the anterior choroidal artery (AChA) on CT and/or MRI. In each case vascular occlusion in the region was verified angiographically. Although the extent of the lesion on CT/MR images was variable, all were located on the axial images within an arcuate zone between the striatium anterolaterally and the thalamus posteromedially. The distribution of the lesions on mutiplanar MRI conformed well to the territory of the AChA demonstrated microangiographically. The variability of the extent of the infarcts may be explained by variations in the degree of occlusive changes in the AChA or the development of collateral circulation through anastomoses between the AChA and the posterior communicating and posterior cerebral arteries. The extent of the lesion appeared to be closely related to the degree of neurological deficit.  相似文献   
96.
Phosphorylation of the rat brain ryanodine receptor was studied using a monoclonal antibody, Ry-1, against the cardiac ryanodine receptor. A large polypeptide with the same SDS-PAGE mobility as that of the canine cardiac receptor was detected in rat brain membranes by immunoblotting. The brain ryanodine receptor was solubilized from the microsomal membranes with 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonic acid (CHAPS), and more than 85% of the solubilized receptor was immunoprecipitated by Ry-1. Immunoprecipitated receptors were phosphorylated by cAMP-dependent protein kinase. The ryanodine receptor was also expressed in cultured fetal rat brain neurons and was phosphorylated by treating the cells with dibutyryl cAMP. The number of cells showing a caffeine-induced Ca2+ transient was increased significantly in the phosphorylating condition. These results suggest that the Ca channel activity of the brain ryanodine receptor is regulated by cAMP-dependent phosphorylation.  相似文献   
97.
MR angiography (MRA) was performed in 50 consecutive subjects (mean age, 59 years), who had been referred for abdominal MRA, on a 1.5-T superconductive unit that used a body phased-array coil. Three breath-hold three-dimensional sequences were evaluated both in phantom and clinical studies: (a) standard fast three-dimensional gradient-echo sequence (TR = 15, TE = 6; imaging time, 32 seconds), (b) ultrafast three-dimensional gradient-echo sequence (TR = 8.2, TE = 3; imaging time, 18 seconds), and (c) ultrafast magnetization-prepared (MP) rapid acquisition gradient echo (RAGE) (TR = 5.8, TE = 2.9, inversion time [TI] = 20; imaging time, 15 seconds). The initial 30 patients were randomized into three groups by three separate sequences. For the remaining 20 patients, ultrafast-gradient-echo and ultrafast MP-RAGE sequences were performed. Conventional angiography was performed on 36 patients. Signal measurements of the phantom and clinical images of the aorta, visceral branches of the aorta, iliac arteries, inferior vena cavae, and portal veins were performed. The overall image quality and background fatty tissue contrast of the vessels were rated subjectively. Comparison of images between MRA and conventional angiography also was performed. The contrast between the vessels and background fatty tissue was significantly higher in the ultrafast MP-RAGE sequence in both quantitative and qualitative analysis, and image-quality ultrafast MP-RAGE was superior to the other two sequences (P < .01). The aorta and iliac arteries could be visualized in all pulse sequences, and abnormalities of these vessels were diagnosed correctly. The renal artery was visualized more clearly with the two ultrafast sequences.  相似文献   
98.
A rabbit cervix preparation designed to evaluate the effects of locally administered substances and those of prelabor contractility on cervical ripening is described. In one experiment, one of the two cervices was exposed to prostaglandin E2 gel and the contralateral cervix was exposed to plain gel. In another experiment, one cervix was completely isolated from prelabor contractility, whereas the contralateral cervix remained intact. Cervical ripening was assessed by measurement of the stretch modulus and rate of creep 2 days later. Treatment with prostaglandin E2 gel and exposure to prelabor contractility resulted in significant unilateral cervical changes, suggesting that at least part of the prostaglandin E2 effect is locally mediated and that spontaneous prelabor contractility may play a role in cervical preparation for labor. Furthermore, because of its simplicity, this animal preparation can be useful in the investigation of the effects of other locally administered substances on cervical ripening.  相似文献   
99.
Summary Histological, ultrastructural and morphometrical observations on Clarke's column were carried out in 18 patients with sporadic amyotrophic lateral sclerosis (ALS) and 15 age-matched control subjects. Of the 18 ALS patients 6 had been on a respirator before death. Bunina bodies were found in the neuronal cytoplasm in 7 of the 12 non-respirator-supported ALS patients and in 3 of the 6 respirator-supported patients. The number of spheroids was significantly higher in the non-respirator-supported patients (P<0.01) than in the control subjects; however, the number in the respirator-supported patients was about equal to that in the controls. The number of neurons in Clarke's column in the non-respirator-supported ALS patients was not reduced, but in the respirator-supported patients they tended to disappear with time after respiratory support. These findings suggest that Clarke's column neurons are also involved primarily in the disease process in sporadic ALS. However, they may begin to disappear only after the patients require respiratory support.Supported in part by a research grant for CNS degenerative diseases from the Ministry of Health and Welfare, Japan  相似文献   
100.
We present a patient with vertebrobasilar insufficiency, with vertigo and horizontal nystagmus, induced by turning the head to the right. Angiography demonstrated transient occlusion of the left vertebral artery at the atlantoaxial joint during rotation of the head. The pathogenesis and angiographic findings are discussed.  相似文献   
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