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991.
The in vitro exposure of rat bronchial smooth muscle to the acetylcholinesterase inhibitor soman (0-[1,1,2-trimethylpropyl]-methylphosphonofluoridate) reduced the potassium (51 mM) evoked release of 3H-acetylcholine (3H-ACh). Exposure to 1.0 and 100 microM soman for 15 min inhibited the acetylcholinesterase (AChE) activity completely and reduced the potassium evoked release by 23.1% and 34.4% respectively. In the presence of scopolamine (0.3 microM), however, there was a large enhancement (87.0%) of potassium evoked release during soman inhibited (100%) AChE-activity. Furthermore, soman (1.0 microM) did not reduce the spontaneous release of 3H-ACh. The results indicate that the presynaptic effect of soman is due to the enhanced concentration of ACh following AChE-activity inhibition in the synaptic region. This induces a stimulation of presynaptic muscarinic receptors and thereby modulation of the ACh release only during evoked release.  相似文献   
992.
Urinary excretion of N-acetyl-beta-glucosaminidase (NAG) is an early marker of nephrotoxicity. NAG activity was assayed by the fluorimetric method of Leaback and Walker in 17 patients treated (22 courses) with carboplatin (CBDCA, 220-550 mg/m2) before infusion and 24, 48, 72 and 96 h after. Increased excretion of NAG, a sensitive index of renal tubular damage, was observed following 10 of the 22 courses. A transient increase in plasma creatinine and/or abnormal proteinuria was observed in 6 cases. Impaired renal function prior to therapy seems to be a predisposing factor to the nephrotoxicity.  相似文献   
993.
Since the beginning of this century, trans- naso-sphenoidal resection of the pituitary fossa tumors has been widely used clinically. It has more merits than other operative approaches used before. In China it has been adopted by both ENT doctors and neurosurgeons since 1959.1 In order to afford some relevant anatomical data, we measured 137 adult sagittal plane skulls with distinct landmarks.  相似文献   
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This report describes four siblings affected with familial intrahepatic cholestasis detected in early infancy. In the two male siblings, biliary cirrhosis and fatal hepatocellular carcinoma later developed, whereas the female siblings have had persistent hepatomegaly and recurrent episodes of cholestasis. Sequential biopsies show that this rare disorder of unknown etiology must be added to the many causes of giant cell transformation of the liver in infancy. Its oncogenic risk, particularly in males, has not been generally appreciated.  相似文献   
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Molecular probes that are tightly linked to and flank the Duchenne muscular dystrophy (DMD) locus, have been used to characterize DMD mutations and diagnose female carriers. Deletions within the Xp21 region were identified for 8 of 71 families studied. Using both DNA and CK studies, accurate (96 to 98%) carrier or noncarrier diagnoses were made for 51 of 75 females at risk in 24 families with a single affected male. DNA studies resulted in an alteration of predicted risk in 40% of the cases. Recombinant diagnostic methods are useful for carrier detection in families with one or more affected males.  相似文献   
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