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1.
We studied the trigeminal and facial motor nuclei of the hagfish by the retrograde HRP method. We distinguished 4 components in a single column of the motor nuclei of the trigeminal nerve and the facial nerve, viz., the pars magnocellularis of the trigeminal motor nucleus (mVm), the anterior part of the pars parvocellularis of the trigeminal motor nucleus (mVp1), the posterior part of the pars parvocellularis of the trigeminal motor nucleus (mVp2) and the facial motor nucleus (mVII). Although in Nissl preparations only the mVm could be distinguished from the rest of the nucleus, the boundaries of the other 3 components were clearly demarcated in HRP preparations. Intramuscular injections into two representative antagonistic jaw muscles revealed that there was no apparent topological organization of the neurons pertaining to the opening and closing muscles in the mVm and mVp1, but both antagonistic muscles were innervated bilaterally. Although the hagfish does possess a cartilaginous jaw, the organization pattern of the motor nuclei of the jaw muscles seems to be the most primitive of all living vertebrates.  相似文献   
2.
Four of 82 patients with Guillain-Barré syndrome (GBS) and 1 of 12 with multifocal motor neuropathy (MMN), who previously had had Mycoplasma pneumoniae infections, had serum antibody to galactocerebroside (Gal-C). Two patients with GBS without mycoplasma infection also had anti-Gal-C antibody, whereas none of the normal or the disease controls had it. As Gal-C is a major glycolipid antigen in myelin, anti-Gal-C antibody may function in the pathogenesis of autoimmune demyelinative neuropathies. Mycoplasma pneumoniae appears to be an important preceding infectious agent in autoimmune neuropathies with anti-Gal-C antibody. © 1995 John Wiley & Sons, Inc.  相似文献   
3.
A 52‐year‐old Japanese woman who presented with gastrointestinal (GI) bleeding underwent a proximal gastrectomy for a gastrointestinal stromal tumor (GIST) with a foveolar hyperplasia at the apex of the tumor, 4.5 cm in size, located in the upper body of the stomach. Although GIST are often asymptomatic and are found only incidentally, clinical symptoms such as bleeding, abdominal pain, or obstruction, occasionally lead to a premorbid diagnosis. When submucosal tumors present GI bleeding, the source of the bleeding usually is an ulceration of the mucosa over the tumor. However, in the present study, it was thought that the bleeding originated from the region of foveolar hyperplasia.  相似文献   
4.
We recorded neurons sensitive to depth movement from the inferior parietal lobule (area 7a) of alert behaving monkeys, and studied their response to changing sizes of retinal images and to changing binocular disparity. The size of the stimulus was changed by changing both the height and width of a slit in the same way, and the disparity change was produced by varying distances between a pair of polarized stimuli on a screen. Of 227 purely visual neurons recorded from 11 hemispheres of 7 monkeys, 32 neurons responded to the change of either the size or disparity, or both. Some of the neurons sensitive to size change could be activated by changing length on only one axis, but the optimal stimulus for most of them was a uniform change of size in all directions. The neurons sensitive to disparity change responded weakly to monocular stimuli, but showed clear selectivity in the direction of change of disparity when binocular stimuli were applied. We also found a group of depth movement sensitive neurons that responded maximally to the simultaneous change of size and disparity. This type of neurons may signal real depth movement by integrating the signals of size change and disparity change.  相似文献   
5.
6.
Serum levels of CA-50, SLX and ST-439 were measured in 213 patients with lung cancer (92 adenocarcinomas, 63 squamous cell carcinomas, 37 small cell carcinomas and 21 large cell carcinomas) and 87 patients with benign lung disease. The overall positive rates in patients with lung cancer were 12.8% for CA-50, 29.7% for SLX and 25.3% for ST-439. The positive rates for CA-50, SLX and ST-439 in adenocarcinoma patients were 22.8%, 42.4% and 38.0%, respectively. Of the patients with benign lung disease, 4.8% were false positive for CA-50, 15.3% for SLX and 3.6% for ST-439. In the patients with adenocarcinoma of the lung, the combination assay of CEA and ST-439 had a highly accurate rate (61.9%).  相似文献   
7.
The effect of gamma-aminobutyric acid (GABA) on the human internal anal sphincter was investigated. Cumulative applications of GABA produced concentration-dependent contractions (10(-8)-10(-5) M) of the isolated human sphincter. Pretreatment with bicuculline (GABAA antagonist) turned them to relaxation. Muscimol, a GABAA agonist, induced concentration-dependent contractions (10(-8)-10(-5) M); however, baclofen (GABAB agonist, 10(-8)-10(-5) M) promoted concentration-dependent relaxation of the strips. These results suggested that both excitatory GABAA receptors and inhibitory GABAB receptors exist in the internal anal sphincter. Oral administration of sodium valproate (1600 mg/day), a GABA transaminase inhibitor, enhanced the anal canal resting pressure in 10 normal volunteers. Anal manometry showed a significant elevation in tonus without affecting amplitudes or frequencies. These results indicated that endogenous GABA, which was increased by sodium valproate, produced elevations in the anal canal resting pressure through its specific receptors in the human internal anal sphincter.  相似文献   
8.
Protein kinase C (PKC) activity was examined in the cytosolic and particulate fractions of homogenates obtained from 12 papillary thyroid carcinomas, 12 follicular thyroid adenomas, and the adjacent normal thyroid tissue. Particulate PKC activity was elevated significantly in thyroid carcinomas compared with normal thyroid tissue (P < 0.01) and adenomas (P < 0.05). By contrast, cytosolic PKC activity of carcinomas and adenomas was lower significantly than that of normal thyroid tissue (P < 0.01). The percentage of particulate PKC activity in carcinoma and adenoma was higher than in normal thyroid tissue (carcinoma, P < 0.001; adenoma, P < 0.01). The average particulate PKC activity of carcinomas more than 3 cm in diameter was significantly lower than that of carcinomas less than or equal to 3 cm in diameter (P < 0.05). The average cytosolic PKC activity of carcinomas more than 3 cm also was lower significantly than that of smaller carcinomas (P < 0.05). These results suggest that alterations in PKC activity may be important in the development of papillary thyroid cancer.  相似文献   
9.
Five patients with acromegaly and five patients with prolactinoma undergoing general anaesthesia were studied. Concentrations of plasma growth hormone in patients with acromegaly and concentrations of plasma prolactin in patients with prolactinoma were measured before anaesthesia, when 250 mg levodopa was administered orally, and after anaesthesia when dopamine was infused intravenously at a rate of 5 micrograms/kg.min. There was no difference in hormonal (growth hormone or prolactin) response to either treatment in the anaesthetized and the awake states. These findings indicate that the functioning of dopamine receptors in the anterior pituitary is not affected by anaesthesia.  相似文献   
10.
The results of treating 12 consecutive patients with unresectable colorectal hepatic metastases with a hepatic arterial infusion of high-dose Adriamycin, 100–120 mg/m2, using hepatic venous isolation (HVI) and charcoal hemoperfusion (CHP) are reported herein. Adriamycin was administered over 5–15 min under extracorporeal drug elimination by HVI-CHP. HVI was percutaneously accomplished by either the double-balloon technique using a Fogarty occlusion catheter (8/22F) or a balloon-tipped catheter (16F). During the infusion, isolated hepatic venous blood was filtered by CHP and pumped into the left axillary vein. There were no lethal complications, and good hemodynamic tolerance to HVI-CHP was confirmed. Tumor liquefaction accompanied by a sharp decrease in serum carcinoembryonic antigen levels by more than 50% of pretreatment levels was observed in 6 of the 12 patients 1 month after treatment. Apart from chemical hepatitis, which developed in 11 (92%) of the patients, the Adriamycin toxicities were well controlled following the development of nausea and vomiting in 2 patients (17%), leukopenia <2,000/mm3 in 3 (25%), and gastric ulcer in 1 (8%). These results indicate that this method is a safe and useful procedure for otherwise hazardous high-dose intraarterial chemotherapy in patients with unresectable hepatic tumors.  相似文献   
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