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91.
Following administration of phenothiazines for schizophrenia, a 25-year-old patient developed a malignant neuroleptic syndrome followed by bilateral periarticular ossification of the knees, with severely limited motion. Two years later, the patient regained useful motion after bilateral excision of the ossified tissue and intensive physiotherapy. No recurrence of ossification was observed 3 years after operation, and the patient has maintained almost normal motion.  相似文献   
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Background: Mitochondrial adenosine triphosphate-sensitive potassium (mitoKATP) channels play a pivotal role in mediating cardiac preconditioning. The effects of intravenous anesthetics on this protective channel have not been investigated so far, but would be of importance with respect to experimental as well as clinical medicine.

Methods: Live cell microscopy was used to visualize and measure autofluorescence of flavoproteins, a direct reporter of mitoKATP channel activity, in response to the direct and highly selective mitoKATP channel opener diazoxide, or to diazoxide following exposure to various anesthetics commonly used in experimental and clinical medicine. A cellular model of ischemia with subsequent hypoosmolar trypan blue staining served to substantiate the effects of the anesthetics on mitoKATP channels with respect to myocyte viability.

Results: Diazoxide-induced mitoKATP channel opening was significantly inhibited by the anesthetics R-ketamine, and the barbiturates thiopental and pentobarbital. Conversely, urethane, 2,2,2-trichloroethanol (main metabolite of [alpha]-chloralose and chloral hydrate), and the opioid fentanyl potentiated the channel-opening effect of diazoxide, which was abrogated by coadministration of chelerythrine, a specific protein kinase C inhibitor. S-ketamine, propofol, xylazine, midazolam, and etomidate did not affect mitoKATP channel activity. The significance of these modulatory effects of the anesthetics on mitoKATP channel activity was substantiated in a cellular model of simulated ischemia, where diazoxide-induced cell protection was mitigated by R-ketamine and the barbiturates, while urethane, 2,2,2-trichloroethanol, and fentanyl potentiated myocyte protection.  相似文献   

95.
Both dopamine D1 and D2 receptors are present in rat retina. D1 receptors are positively coupled to adenylyl cyclase, while D2 receptors are negatively coupled. After intraocular administration of the neurotoxin 6-hydroxydopamine (6-OHDA) there is depletion of retinal dopamine by about 90%, as well as a decrease of the number of D1 and D2 receptor binding sites. Following the 6-OHDA lesion, there is an enhancement of the D1 receptor-stimulated accumulation of cyclic-AMP and a loss of D2 receptor-inhibited accumulation of cyclic-AMP. Our results suggest that some of the retinal D2 receptors are coupled to adenylyl cyclase and some are not.  相似文献   
96.
Q Guo  Z Guo 《中西医结合杂志》1989,9(8):472-4, 452
The effect of the traditional Chinese medicinal herbs enema and enteric-coated capsules in the treatment of ulcerative colitis (UC) were compared in 260 cases. The immune complexes and the dynamic change of autoantibodies were monitored in 28 out of the 260 cases before and after treatment. The following results were observed. (1) There was no significant difference in the total effective rate between the enema group and the oral capsule group (93.3% and 87.5% respectively), but the recovery rates of purulent hemafecia, mucusfecia and erosion accompanying colitis, etc. in the former group were higher than those in the latter (P less than 0.01). (2) The circulating immune complexes were found 43 times above the normal range in 17 cases with positive rate 60.7%, and tended to decrease as the condition became better after treatment. Antinuclear antibodies were determined by the indirect fluorescent immune method and the indirect enzyme labelling method and the positive rates were 53.6% and 64.7% respectively, both being much higher than those in the controls (P less than 0.01).  相似文献   
97.
A goal for the obstetrician and neonatologist is to screen for risk factors associated with intraventricular hemorrhage (IVH) in the low-birthweight infant. Perinatal events that lead to neonatal metabolic and cardiovascular derangements seem to provoke IVH, and conflicting reports have implicated labor as being contributory. A fetal heart rate (FHR) abnormality during premature labor may be a predictor of subsequent neonatal IVH. For this reason, 5 years of FHR tracings at two university medical centers were reviewed for inborn infants who were delivered after premature labor and weighed less than or equal to 2000 gm. Sixty-four infants developed IVH, but pre-existing labor with a discernible FHR pattern was recorded in only 38 (59%) cases. Interpretations were reassuring in 17 (45%) cases, suspicious in 7 (18%) cases, and ominous in 14 (37%) cases. This proportion of FHR patterns was not significantly different from a matched group of premature infants without IVH during the same period. Interpretations of intrapartum FHR patterns of low-birthweight infants are limited, especially before 30 weeks gestation, and not useful in predicting neonatal IVH.  相似文献   
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The cementoblastoma is a rare benign tumor of odontogen origin that interests the roots of the teeth especially the lower molars. The evolution is often silent, the radiological exam is not specific, the diagnosis of certainty is histological. The surgical treatment assures the recovery without aftermath. The authors report a case of cementoblastoma at a patient of 37 years for which he has benefited of a resection by vestibular way and debate diagnosis and therapeutic modes of this affection.  相似文献   
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