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81.
Sleep-induced changes in the trigeminal neuron responses to electrical stimulation of the cat tooth pulp were studied. Two parameters were adopted: One was the evoked spike number at two times the threshold intensity (2 X T response magnitude), which would reveal the level shifting of the neuronal response by the sleep-regulatory system. Another was the rate of change in the response intensity when the stimulus was raised to a level of 0.7 time the arousal threshold during light slow wave sleep (sensitivity gradient), which would reflect the influences of the pain-modulatory system driven by strong noxious inputs. It was found that during sleep the two indexes tended to show a correlated change; the neurons which came to have a greater 2 X T response magnitude tended to have a smaller sensitivity gradient than during wakefulness, and vice versa. It was suggested that two contrasting populations of tooth pulp neurons might be differentiated, and that the sleep-regulatory system and the pain-modulatory system would have differential but correlated controls over these two kinds of neurons.  相似文献   
82.
83.
Summary Unit activites of secondary vestibular neurons that selectively responded to stimulation of the anterior semicircular canal nerve (ACN) were recorded extracellularly in the anesthetized cat. Axonal pathways and projections in the spinal cord of the ACN-activated neurons were examined by recording their antidromic responses to stimulation of the lateral and medial vestibulospinal tracts (LVST and MVST), and the bilateral neck extensor motoneuron pools in the C1segment (C1dorsal rami [DR] motoneuron pools). In order to determine whether the neurons had ascending axon collaterals to the extraocular motoneurons, the contralateral (c-) inferior oblique (IO) motoneuron pool was also stimulated. Twenty-seven neurons sent their axons to the ipsilateral (i-) C1DR motoneuron pool via the LVST without any projection to the extraocular motoneuron pool. All the cells except one were located in the ventral part of the lateral vestibular nucleus. This pathway produced monosynaptic EPSPs with short time-to-peak and short half-width in C1DR motoneurons (16/16 motoneurons). Eight neurons sent axons to the i-C1DR motoneuron pool via the MVST without any to the extraocular motoneuron pool. Cell somata were located in the descending nucleus or in the ventral part of the lateral nucleus. These neurons did not produce postsynaptic potentials (PSPs) in any C1DR motoneurons. All thirty-five neurons sending axons to the c-C1DR motoneuron pool have ascending axon collaterals to the c-IO motoneuron pool.  相似文献   
84.
An 18-year-old woman with abdominal pain was diagnosed as having splenic cysts by computed tomography scan. She had high serum levels of CA19-9 (2886.8 U/mL; normal value, <35 U/mL), CA125 (131.1 U/mL; normal value, <35 U/mL) and soluble IL-2 receptor (1490 U/mL; normal range, 220-530 U/mL). The resected spleen weighed 1050 g, was 14 x 28 cm, and had more than 10 macroscopic cysts up to 10.3 x 9.5 cm. There were numerous microscopic cysts in the spleen and several on the splenic capsule. The levels of CA19-9 and CA125 in the cyst fluid were 2165550 U/mL and 160400 U/mL, respectively. After the surgery, the serum levels of the tumor markers decreased gradually. The inside of the largest cyst was mainly covered by granulation tissue with a focal lining of epithelial cells, and the other macroscopic cysts had stratified squamous epithelium. The microscopic splenic cysts and cysts on the splenic capsule were lined by either attenuated single-layered or multilayered epithelial cells. The lining epithelial cells of these cysts were positive for epithelial membrane antigen and cytokeratins. CA19-9 and CA125 were detected in the lining cells of the splenic cysts. In the present case, it is suspected that the splenic cysts were derived from the capsular lining cells that showed migration from the capsule or formed microcysts on the splenic capsule, as in the case of ovarian inclusion cysts.  相似文献   
85.
We previously generated a strain of transgenic mice carrying the human renin gene, hRN8-12, in the background of C57BL/6j. In this study, we discovered that hRN8-12 male mice, but not females, developed obesity starting at 15 weeks of age. The body weight of 60-week-old male transgenic mice was 2 times higher than that of age-matched wild-type mice. Interestingly, male mice heterozygous for the human renin gene showed moderate weight gain compared with transgenic and wild-type mice. Obese hRN8-12 mice exhibited hyperglycemia, hyperinsulinemia, hyperleptinemia, and hyperlipidemia, and increase in weight in the adipose tissue, liver, heart, and kidneys. Histological analysis demonstrated that fatty hRN8-12 mice developed hypertrophy of pancreatic islets and fatty liver. These results suggested that hRN8-12 mice are associated with obesity dependent on the transgene dosage and should be a genetic model for late-onset obesity.  相似文献   
86.
A 10-year-old child was diagnosed as subacute necrotizing lymphadenitis. After a steroid hormone (predonine) administration for 17 days, he showed total cholesterol(TC) 420 mg/dl, triglyceride(TG) 839 mg/dl, and LDL-cholesterol 241 mg/dl. The hyperlipidemia seemed to be a side effect of the steroid at the onset. However, the lipoprotein fraction by the agarose gel and polyacrylamide gel (PAG) electrophoresis showed type III of the WHO classification, that is, presence of broad band as well as appearance of mid band, small dense-LDL and the disrupted type of LDL band. In addition, there were hyperlipidemia (high levels of the TC, TG, LDL-cholesterol) in 4 persons out of 6 family members, and LDL pattern of the PAG electrophoresis, 4 persons showed the nodular type. They have higher possibility of combined-type familial hyperlipiemia from the above results, and it seemed to be the case in which the hyperlipidemia was exacerbated by the steroid administration.  相似文献   
87.
Summary In a study of 277 patients with breast carcinomas, the PAP immunoperoxidase method for demonstrating endogenous estrogen was correlated with the sucrose density gradient (SDG) assay and with histologic and clinical features. The results from the PAP method and SDG assay agreed in 59 of 84 patients (82.1%) on whom both methods were performed. Histologically, the PAP method was positive in 7 of 7 patients with non-invasive carcinomas, in 164 of 233 patients (70.4%) with common invasive ductal carcinoma, and in 21 of 22 of those with special histological types of invasive carcinomas not including Paget's disease, medullary or apocrine carcinoma, where only 5 of 14 were positive. Clinically, 15 of 18 patients with positive endogenous estrogen showed a response to endocrine therapy as opposed to 1 of 9 patients with a negative endogenous estrogen. The mean survival was 31.2 and 15.6 months, respectively for patients with positive and negative endogenous estrogen. Remission for longer than 2 years was seen more often in patients with positive endogenous estrogen. These results suggest a clinical utility of the present PAP method which, therefore, deserves a further trial as an alternative to histochemical methods aiming at the estrogen receptors.This work was supported by Grants-in Aid for Scientific Research from the Ministry of Education, Science, and Culture of Japan (No. 56480119).This paper was presented at the 72nd Annual Meeding of International Academy of Pathology (United States-Canadian Division), Atlanta, Georgia, March 1, 1983.  相似文献   
88.
The endometrium is a highly regenerative tissue that plays a crucial role in implantation. We examined the clonal constitution of glandular cells as well as the luminal epithelium of this unique tissue. Using collagenase-based digestion techniques with microscopic manipulation, we isolated individual human endometrial glands and examined their clonality using a polymerase chain reaction-based assay for nonrandom X chromosome inactivation with an X-linked androgen receptor gene. Most of the glands analyzed were composed of monoclonal populations of epithelial cells and one of the glands exhibited a loss of heterogeneity in the androgen receptor gene. In addition, adjacent glands within a 1-mm(2) area shared clonality, suggesting that clonality of the luminal epithelium is regionally defined. The clonality of endometrium was further confirmed in a study of female mice that harbor the green fluorescent protein gene on either the maternal or paternal X chromosome. Fluorescent microscopy of uterine sections revealed that individual endometrial glands consisted completely of either fluorescent or nonfluorescent cells and that the surface epithelium exhibited a clear boundary between these cell types. These findings suggest that single or multiple stem cells with uniform clonality exist on the bottom of each endometrial gland and genetic alterations occurring in such cells may play a critical role in endometrial carcinogenesis. The possible association between area-specific X inactivation of the endometrial surface and the endometrial receptivity of embryo implantation remains to be clarified.  相似文献   
89.
90.
The proliferative capacity of brain-tumor cells was analyzed in vitro and in situ using monoclonal antibody (MAb) against deoxyribonucleic acid (DNA) polymerase alpha. For the in vitro studies, two cultured human glioma cell lines were investigated using MAb against DNA polymerase alpha, the MAb Ki-67, a serum against proliferating cell nuclear antigen (PCNA/cyclin), bromodeoxyuridine (BUdR), and an anti-BUdR MAb. During exponential growth of the cells, the percentage of polymerase alpha-positive cells (the "polymerase alpha score") ranged from 72.0% to 77.1%, the Ki-67-positive cells (the "Ki-67 score") ranged from 43.4% to 59.4%, the PCNA/cyclin-positive cells from 30.9% to 41.4%, and the BUdR labeling index from 28.6% to 39.3%. For the in situ studies, tissue from 60 human brain tumors and from two normal human brains was investigated and the polymerase alpha scores and Ki-67 scores were compared. In normal brain tissue, no immunostaining was found by either method. In brain tumors, both the polymerase alpha scores and the Ki-67 scores correlated with the histological grade of malignancy. Polymerase alpha scores were generally higher than Ki-67 scores in the same specimen, especially in malignant brain tumors. These findings suggest that immunostaining of DNA polymerase alpha is a convenient and important new method by which to estimate the cellular proliferation rate of brain tumors. Polymerase alpha scores may be closer to the growth fraction of the individual tumor than the MAb Ki-67 or other scores.  相似文献   
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