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11.
A 46-year-old man presented with sore throat. Laryngoscopic findings revealed a smooth yellow mass occupying the anterior portion of the false vocal fold on the left side. The authors performed biopsy under general anesthesia. The histopathological diagnosis was ectopic salivary gland. Because salivary glands are usually not found under the false vocal fold mucosa, ectopic salivary gland of the larynx was diagnosed.It is necessary to consider the possibility of ectopic salivary gland for mass lesions if swelling of the provisional vocal cord is found.  相似文献   
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Abstract: A simple high-performance liquid chromatographic method that allowsthe determination of 10 biogenic amines and related compounds for crude brain extracts has been developed. The compounds that can be quantified comprise norepinephrine, epinephrine, 3,4-dihydroxyphenylacetic acid, 3-methoxy-4-hydroxyphenylglycol, dopamine, 5-hydroxyindole-3-acetic acid, homovanillic acid, 3-methoxytyramine, 5-hydroxytryptamine and tryptophan. The detection system involves a three electrode-coulometric determination followed by fluorometric determination. This method is highly selective and sensitive, and in the present study, the usefulness of this methodology was confirmed by applying it to the determination of the levels of these various substances in 11 rat brain regions.  相似文献   
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Abstract: The relationships between the side effects of maprotiline (MPT) andthe serum concentration of MPT and desmethylmaprotiline (DMPT) were investigated with 27 blood samplings in 15 depressed inpatients. There were significant correlations between the side effects and serum levels of MPT and DMPT. Mild side effects frequently occurred at levels of more than 130 ng/ml of MPT and 70 ng/ml of DMPT. At more than 220 ng/ml of the MPT levels and 110 ng/ml of DMPT levels, severe side effects occurred. Nearly sigmoidalserum level/side effect response curves occurred with both compounds.  相似文献   
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We examined the brain activation induced by a complex finger movement task using functional magnetic resonance imaging (fMRI) with echo planar imaging (EPI). Imaging planes were set up for the observation of non-primary motor areas. Among five normal males examined, four subjects naive to the task showed activations in contralateral primary and supplementary motor areas and the ipsilateral superior anterior part of the cerebellar hemisphere. Also, the bilateral premotor areas and the contralateral ventrolateral nucleus of thalamus were occasionally activated. No changes were observed in the putamen and globus pallidus. The subject accustomed to the task showed activation in the narrow areas of the contralateral primary motor and supplementary motor and premotor areas but not in the cerebellum. These results suggest that fMRI has nearly the same degree of detectability to that of positron emission tomography (PET) in regard to motor functions.  相似文献   
15.
Endogenous cannabinoids (endocannabinoids) act as retrograde inhibitory messengers in various regions of the brain. We have recently reported that endocannabinoids mediate short-term retrograde suppression of excitatory synaptic transmission from the neocortex to medium spiny (MS) neurons, the major projection neurons from the striatum. However, it remains unclear whether endocannabinoids modulate inhibitory transmission in the striatum. Here we show that depolarization of MS neurons induces transient suppression of inhibition that is mediated by retrograde endocannabinoid signalling. By paired recording from a fast-spiking (FS) interneuron and an MS neuron, we demonstrated that FS-MS inhibitory synapses undergo endocannabinoid-mediated retrograde suppression. We verified that GABAergic inhibitory terminals immunopositive for parvalbumin (PV), a marker for FS interneurons, expressed CB1 receptors. These PV-CB1 double-positive terminals surrounded dopamine D1 receptor-positive and D2 receptor-positive MS neurons; these constitute direct and indirect pathways, respectively. These results suggest that endocannabinoid-mediated retrograde suppression of inhibition influences information flow along both direct and indirect pathways, depending on the activity of MS neurons.  相似文献   
16.
The rat neostriatum has a mosaic organization composed of striosome/patch compartments embedded in a more extensive matrix compartment, which are distinguished from each other by the input-output organization as well as by the expression of many molecular markers. The matrix compartment gives rise to the dual γ-aminobutyric acid (GABA)ergic striatofugal systems, i.e. direct and indirect pathway neurons, whereas the striosome compartment is considered to involve direct pathway neurons alone. Although the whole axonal arborization of matrix striatofugal neurons has been examined in vivo by intracellular staining, that of striosome neurons has never been studied at the single neuron level. In the present study, the axonal arborizations of single striosome projection neurons in rat neostriatum were visualized in their entirety using a viral vector expressing membrane-targeted green fluorescent protein, and compared with that of matrix projection neurons. We found that not only matrix but also striosome compartments contained direct and indirect pathway neurons. Furthermore, only striatonigral neurons in the striosome compartment projected directly to the substantia nigra pars compacta (SNc), although they sent a substantial number of axon collaterals to the globus pallidus, entopeduncular nucleus and/or substantia nigra pars reticulata. These results suggest that striosome neurons play a more important role in the formation of reward-related signals of SNc dopaminergic neurons than do matrix neurons. Together with data from previous studies in the reinforcement learning theory, our results suggest that these direct and indirect striosome-SNc pathways together with nigrostriatal dopaminergic neurons may help striosome neurons to acquire the state-value function.  相似文献   
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Interstitial cells of Cajal (ICC) are believed to lnitlate the basic contractile activity of the gastrointestlnal tract. Interstitial cells of Cajal express c-kit receptor tyroslne kinase and are deficient in Ws/Ws mutant rats with a small deletion of the c-kit gene . As Ws/Ws rats show remarkable bile reflux to the stomach, the contraction pressure of the pylorus was compared between Ws/Ws and control +/+ rats. The contraction pressure of the pylorus was measured using a mlcrotransducer, which was Inserted through a pln-hole in the anterlor wall of the stomach under anesthesla. The magnitude of bile reflux was estimated by measurlng the content of bile acids In the stomach. The c-kit messenger RNA-expressing cells were detected by in sltu hybrldlzatlon. Frequency and the maxlmum pressure of the contractlon were comparable between Ws/Ws and +/+ rats, but the duration of the contractlon was significantly shorter In Ws/Ws rats than In +/+ rats. The number of c-kit messenger RNA-expresslng ICC in the pylorus of Ws/Ws rats was 1.7% that of +/+ rats. The bile reflux observed in Ws/Ws rats was attributed to the decrease in the duration of the pyloric contraction, which appeared to result from the deficlency of c-kit messenger RNA-expressing ICC.  相似文献   
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