3226
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Yang ZY, Zhang LJ, Wang M. [Preliminary evaluation of the combination of Chinese herbal medicine (destagnation) and radiotherapy for esophageal cancer]. ZHONGHUA ZHONG LIU ZA ZHI [CHINESE JOURNAL OF ONCOLOGY] 1987; 9:48-9. [PMID: 3297588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
From May 1973 to March 1979, a prospective randomized clinical trial on 425 patients with esophageal cancer was conducted. 194 patients were allotted into the destagnation plus radiotherapy group, the other 231 into radiotherapy only group. The result shows that the combination of destagnation and radiotherapy does not give a result superior to radiotherapy alone. However, destagnation does not increase either hematogenous, lymphatic metastasis, perforation or hemorrhea of the esophageal cancer.
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3227
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Yin WB, Zhang HX, Zhang LJ, Yang ZY, Zhang ZX, Miao YJ, Wang M, Gu XZ, Cao DX, Jia YQ. [Carcinoma of esophagus treated by 8MV X-ray and checked by simulator]. ZHONGHUA ZHONG LIU ZA ZHI [CHINESE JOURNAL OF ONCOLOGY] 1986; 8:474-6. [PMID: 3107956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
From January 1, 1978 to December 31, 1983, 570 patients with carcinoma of esophagus were treated by 8 MV X-ray and checked by the Philips simulator. In order to assess their value, a series of 3,798 patients reported previously was used for comparison. To further evaluate the effect of 8 MV X-ray and simulator separately, a series of 154 patients was treatment by non-8 MV X-ray during the same period. The results showed that the 1 and 3 year survival rates of 8 MV X-ray series were better than the 3,798 series (P less than 0.01). It means that after the use of simulator and 8 MV X-ray the survival rates were improved. As compared to the radiation other than 8 MV X-ray, there was no difference between 8 MV X-ray and non-8 MV X-ray series, which means that the improvement may have been due to the better localization by the simulator. Having more importance, no radiation myelitis was found after the use of simulator. The sex, age, length, location, X-ray type, NSD and causes of failure were compared in these groups.
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3228
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Zhang LJ, Yin WB, Yang ZY, Zhang ZX, Miao YJ, Wang M. [Superior sulcus cancer of the lung--report on 45 patients]. ZHONGHUA ZHONG LIU ZA ZHI [CHINESE JOURNAL OF ONCOLOGY] 1986; 8:458-60. [PMID: 3582117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
From 1960 to 1980, 45 patients with superior sulcus cancer of the lung were seen in our hospital. 39 were male and 6 were female. The youngest was 28 years old and the eldest was 75. The presenting symptoms and signs were back and shoulder pain in 32 patients, compression of the brachial plexus in 17, Horner's syndrome in 12, supraclavicular mass in 11, superior cava vena obstruction in 4, shadow in the apex in 45, destruction of the rib in 19 (10 in the second rib), destruction of the adjacent vertebra in 8 (5 in T3) and destruction of the clavicle in 1. In 18 patients proved by pathology and cytology, 8 were adenocarcinoma, 3 squamous cell carcinoma, 3 undifferentiated and 4 unclassified carcinoma. 27 patients were diagnosed by X-ray films. 40 patients were admitted for treatment. 3 recieved chemotherapy alone and all of them died in one year. Of the 6 treated by radiation plus chemotherapy, 3 survived for one year but all died in two years. 2 were treated by radiation plus operation and none survived for more than 3 years. 29 were treated by radiation only. The 1, 3 and 5 year survival rates were 51%, 13.7% and 6.9%. Destruction of the rib or the adjacent vertebral body was irrelative to the prognosis but the presence of supraclavicular mass reduced the survival rate. Cause of death was local recurrence in 48% (13/27) and distant metastasis in 48% (13/27). The authors suggest that radical en bloc resection together with radiation the worth further study.
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3229
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Desigan G, Wang M, Wofford B, Dunn GD, Vaughan S. Occult gastric cancer manifested by progressive shortness of breath in a young adult. South Med J 1986; 79:1173-6. [PMID: 3018944 DOI: 10.1097/00007611-198609000-00037] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
We have reported a case of occult, diffuse gastric cancer in a young adult with progressive shortness of breath and bilateral pulmonary interstitial infiltrates. Progressive shortness of breath may be the first or only manifestation of occult gastric cancer caused by either lymphangitic carcinomatosis or microscopic tumor emboli to the lungs. Widespread recognition of this syndrome, a high index of suspicion, and prompt lung biopsy are necessary to make the correct diagnosis. With progress in chemotherapy for malignant diseases, early diagnosis and specific treatment may improve the prognosis of this condition.
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3230
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Wu YS, Wang M, Song RF. [Vasorelaxant activities of atriopeptin III and blood activator no. II]. ZHONG XI YI JIE HE ZA ZHI = CHINESE JOURNAL OF MODERN DEVELOPMENTS IN TRADITIONAL MEDICINE 1986; 6:546-8, 517. [PMID: 2947729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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3231
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Mullen BJ, Wang M. Activities of cerebral dihydropteridine reductase and tyrosine hydroxylase in chronic uremia in rats. J Nutr 1986; 116:1298-305. [PMID: 2875142 DOI: 10.1093/jn/116.7.1298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
The effect of chronic uremia on activities of cerebral dihydropteridine reductase (DHPR) and tyrosine hydroxylase (TH) and content of norepinephrine and dopamine was investigated in the male Sprague-Dawley rats. The uremic animals were fed diets containing either 8% or 18% casein ad libitum, and sham-operated pair-fed and ad libitum fed animals were used as controls. There were no significant differences in TH activity between the groups fed the two levels of protein. Uremic rats had lower activity of TH than pair-fed controls, and pair-fed controls had lower activity than ad libitum-fed animals. DHPR activity and norepinephrine and dopamine content did not differ among the groups. Our study suggests that the chronic uremic condition or restricted feeding causes a decrease in brain TH activity which is not mediated by decreased DHPR activity. Further, this decreased enzyme activity does not result in depressed catecholamine content, indicating the presence of a highly regulated mechanism controlling catecholamine levels.
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3232
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Wang M. Changes in psychophysiological and conditioning variables during chlormethiazole-medicated and unmedicated ethanol withdrawal: preliminary report. Acta Psychiatr Scand Suppl 1986; 329:146-52. [PMID: 3463147 DOI: 10.1111/j.1600-0447.1986.tb10552.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Autonomic lability during ethanol withdrawal in chlormethiazole-medicated and unmedicated groups was investigated using electrodermal measures. Vulnerability to Pavlovian aversive conditioning was also assessed. Ethanol withdrawal was associated with increased autonomic arousal and aversive conditioning, suggesting an increased risk of phobia acquisition. Chlormethiazole administered during ethanol withdrawal may protect against such developments.
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3233
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Abstract
Light microscopic studies have indicated that most microtubule-directed transport is either saltatory or resolute in nature. The latter form of transport is an intriguing phenomenon, because it commonly involves the unidirectional bulk motion of an organelle(s) such as chromosomes in dividing cells or pigment granules in chromatophores. We have investigated the ultrastructural and biochemical basis for the resolute transport of pigment in chromatophores. Light and EM studies of erythrophores in situ have clearly shown that when the microtubules were completely removed with nocodazole, resolute transport continued and was stimulated by aggregating and dispersing agents. Light and electron microscopic studies of cultured erythrophores permeabilized with digitonin indicated that resolute motion was produced by a cytomatrix of 3 to 7 nm filaments. Immunofluorescent analysis with several monoclonal antibodies raised against MAP-2 further demonstrated that MAP-2 was an important component of the contractile cytomatrix that powers pigment aggregation and dispersion. We conclude that a microtubule-associated cytomatrix normally produces resolute pigment transport in chromatophores.
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3234
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Schaap P, Wang M. Interactions between adenosine and oscillatory cAMP signaling regulate size and pattern in Dictyostelium. Cell 1986; 45:137-44. [PMID: 3006924 DOI: 10.1016/0092-8674(86)90545-3] [Citation(s) in RCA: 96] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
We present evidence for the hypothesis that in multicellular structures of Dictyostelium, production of adenosine by hydrolysis of cAMP near the tip region prevents both generation of competing tips and differentiation of prespore cells near the tip, and thus establishes a "prestalk" region. We demonstrate that adenosine affects the immunological prespore specific staining pattern in slugs in a manner opposite to cAMP:cAMP induces an increase of prespore antigen; adenosine induces a decrease. When endogenous adenosine is removed from slugs, prespore vacuoles are synthesized throughout the prestalk region. Adenosine was found to inhibit the induction of prespore differentiation by cAMP in an apparently competitive manner. It was also found that adenosine specifically increased the amount of tissue controlled by one tip, probably by inhibiting generation of competing oscillators. Removing endogenous adenosine from slugs resulted in a decrease of tip dominance.
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3235
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Ding MX, Fu HL, Wang M, Zhai ZH, Xiang DL, Zhou QS. [Electron microscopic study of the morphogenesis of goat pox virus]. WEI SHENG WU XUE BAO = ACTA MICROBIOLOGICA SINICA 1986; 26:25-30. [PMID: 3604206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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3236
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Wang M, Cahill AL, Perlman RL. Phorbol 12,13-dibutyrate increases tyrosine hydroxylase activity in the superior cervical ganglion of the rat. J Neurochem 1986; 46:388-93. [PMID: 2867124 DOI: 10.1111/j.1471-4159.1986.tb12980.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Phorbol 12,13-dibutyrate (PDBu) increased the production of 3,4-dihydroxyphenylalanine (DOPA) in the superior cervical ganglion of the rat. This effect occurred without a detectable lag and persisted for at least 90 min of incubation. The action of PDBu was half-maximal at a concentration of approximately 0.1 microM; at high concentrations, PDBu produced about a twofold increase in DOPA accumulation. PDBu increased DOPA production in decentralized ganglia and in ganglia incubated in a Ca2+-free medium. The action of PDBu was additive with the actions of dimethylphenylpiperazinium, muscarine, and 8-Br-cyclic AMP, all of which also increase DOPA accumulation, and was not inhibited by the cholinergic antagonists hexamethonium (3 mM) and atropine (6 microM). Finally, PDBu did not increase the content of cyclic AMP in the ganglion. Thus, the action of PDBu does not appear to be mediated by the release of neurotransmitters from preganglionic nerve terminals, by the stimulation of cholinergic receptors in the ganglion, or by an increase in ganglionic cyclic AMP. PDBu also increased the incorporation of 32Pi into tyrosine hydroxylase. PDBu activates protein kinase C, which in turn may phosphorylate tyrosine hydroxylase and increase the rate of DOPA synthesis in the ganglion.
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3237
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Wang M, Hatlevoll R. [Medulloblastoma. Postoperative treatment]. TIDSSKRIFT FOR DEN NORSKE LEGEFORENING 1986; 106:216-8. [PMID: 3952710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
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3238
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Chung FL, Wang M, Carmella SG, Hecht SS. Effects of butylated hydroxyanisole on the tumorigenicity and metabolism of N-nitrosodimethylamine and N-nitrosopyrrolidine in A/J mice. Cancer Res 1986; 46:165-8. [PMID: 3940189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Female A/J mice were maintained on NIH-07 diet or on NIH-07 diet containing butylated hydroxyanisole (BHA, a mixture of 2- and 3-tert-butyl-4-hydroxyanisole), 5 mg/g, for 1 week prior to and during 10 weeks of treatment with N-nitrosodimethylamine (NDMA) or N-nitrosopyrrolidine (NPYR), administered in the drinking water. Twenty weeks after nitrosamine treatment ended, mice were sacrificed and lung adenomas were counted. BHA inhibited NDMA tumorigenesis but enhanced NPYR tumorigenesis. Treatment of A/J mice for three weeks with BHA (5 mg/g) added to semisynthetic diet increased whole lung microsomal alpha-hydroxylation of NDMA and NPYR, as measured by aldehyde production, and increased lung and hepatic glutathione-S-transferase activities. No evidence was found for formation of S-methylglutathione in incubations with NDMA and hepatic supernatants obtained from BHA treated or control mice. Four h after gavage of NDMA, levels of 7-methylguanine in the lung DNA of mice treated with BHA were higher than in the lung DNA of control mice, but levels of O6-methylguanine in the two groups were the same. The results of this study indicate that BHA treatment increases the microsomal metabolic alpha hydroxylation of both NDMA and NPYR, but has differential effects on their tumorigenic activities.
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3239
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Desigan G, Wang M, Dunn GD, Halter S, Vaughan S. Intramucosal gastric carcinoma in a patient with familial polyposis coli. Am J Gastroenterol 1986; 81:19-22. [PMID: 3942120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Upper gastrointestinal polyps commonly occur in patients with familial polyposis coli; but the occurrence of gastric carcinoma is very rare in this disorder. We report a case of intramucosal gastric carcinoma in a patient with familial polyposis coli and multiple gastrointestinal adenomatous polyps.
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3240
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Abstract
Rectal varices are not hemorrhoids and they are dilated submucosal veins connecting the middle and inferior hemorrhoidal veins. These rectal varices may occur in patients with portal hypertension because of the formation of portosystemic shunts. Like esophageal varices, the rectal varices may also bleed massively. Herein we report a case of such bleeding which was successfully controlled with endoscopic sclerotherapy to the rectal varices.
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3241
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Yu SL, Wang M, Ke CZ, Liu YI, Cao LS, Gao Y, Wu XG, Fu RZ, Wang YS. Evaluation of the effects of tetrandrine on experimental myocardial ischemic and infarct size by cardiothermography. ACTA ACADEMIAE MEDICINAE WUHAN = WU-HAN I HSUEH YUAN HSUEH PAO 1985; 5:153-61. [PMID: 4069497 DOI: 10.1007/bf02911172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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3242
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Desigan G, Wang M, Alberti-Flor J, Dunn GD, Halter S, Vaughan S. De novo carcinoma of the rectum: a case report. Am J Gastroenterol 1985; 80:553-6. [PMID: 4014105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
There is strong evidence in the literature to suggest that most of the colorectal carcinomas arise from adenomatous polyps. Yet, rare carcinomas may arise de novo and we are reporting such a case of intramucosal rectal carcinoma occurring in a 47-year-old healthy man.
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3243
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Wang M, Patel J, Casey TT, Kieffer R, Dunn GD. Metastatic squamous cell carcinoma from the esophagus occurring as small bowel obstruction. South Med J 1985; 78:884-6. [PMID: 3925568 DOI: 10.1097/00007611-198507000-00030] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Metastatic tumors of the small bowel from extra-abdominal sites are rare. The primary tumors that have been reported are malignant melanoma, breast cancer, bronchogenic carcinoma, embryonal myosarcoma, and seminoma. We have presented a case of small bowel obstruction due to metastasis from esophageal cancer.
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3244
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Wang M, McGrew W, Wofford B, Patel J, Dunn GD. Merkel cell tumor with liver metastases: presentation as fulminant hepatic failure. Am J Gastroenterol 1985; 80:376-80. [PMID: 3993638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
This report demonstrates that hepatic metastases can present with fulminant hepatic failure and that liver enzyme abnormalities may not become prominent until there has been massive replacement of the liver. The CT scan of liver may not demonstrate diffuse liver metastases as seen in this patient. Merkel cell tumor or trabecular neuroendocrine skin tumor is a previously unreported cause for the development of the syndrome of hepatic failure due to liver metastases.
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3245
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Schaap P, Wang M. cAMP induces a transient elevation of cGMP levels during early culmination of Dictyostelium minutum. CELL DIFFERENTIATION 1985; 16:29-33. [PMID: 2985287 DOI: 10.1016/0045-6039(85)90604-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Oscillatory cAMP signals very likely organize the cell movement which leads to fruiting body construction in Dictyostelium minutum [Schaap, P., Konijn, T.M. and Van Haastert, P.J.M.: Proc. Natl. Acad. Sci. USA 81, 2122-2126 (1984)]. Stimulation with cAMP induces a transient elevation of cGMP in cells at the early culmination stage, which peaks at 12-18 s. A half maximal cGMP response is induced by 10(-7) M cAMP and saturation of the response is reached at 10(-5) M cAMP. No cGMP accumulation was induced by stimulation of vegetative or aggregative cells of D. minutum by cAMP. Since the transient increase of cGMP is most likely involved in the transduction of chemotactic signals, our results indicate that cAMP signals organize fruiting body formation by inducing chemotaxis inside the aggregate.
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3246
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Ehlers CL, Reed TK, Wang M, Lebrun CJ, Koob GF. EEG effects of subcutaneous and intracerebroventricular injections of arginine vasopressin in the rat. Psychopharmacology (Berl) 1985; 87:430-3. [PMID: 3936102 DOI: 10.1007/bf00432508] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Several studies have suggested that arginine vasopressin (AVP) may act centrally as a neurohormone or neuromodulator to produce electrophysiological and behavioral effects. However, there are few reports of EEG effects of AVP in unanesthetized, behaving animals. In the present study the EEG effects of "behaviorally relevant" subcutaneous (SC) doses of AVP (6 micrograms/kg) known to raise blood pressure were compared to "behaviorally relevant" intracerebroventricular (ICV) doses (0.1-1.0 ng) and multiple "toxic" ICV doses (1.0 microgram) of AVP. Central injections of toxic doses of AVP produced behavioral arrest, bodily barrel rolling, and EEG slowing, but did not induce electrographic signs of seizure activity. Comparison of the spectral characteristics of the EEG revealed some similarities in the distribution of power between SC and the 1.0 ng ICV dose; whereas ICV doses of 0.1 and 0.5 ng produced power distributions that were different from those seen following saline or SC doses of AVP. The similarities in EEG activity between SC injections and the 1.0 ng ICV dose suggest a common brain state may be induced by the two routes of administration in those dose ranges.
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3247
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Guo YJ, Yang DY, Wang P, Wang M, Zhu JM. [A simple and rapid method for concentrating influenza viruses]. ZHONGGUO YI XUE KE XUE YUAN XUE BAO. ACTA ACADEMIAE MEDICINAE SINICAE 1984; 6:468-9. [PMID: 6242553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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3248
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Guo YJ, Wang M, Wang P, Zhu JM, Hu SY, Yuan GQ, Li GC. [Detection of antibody to type B influenza virus in pig populations in China]. ZHONGGUO YI XUE KE XUE YUAN XUE BAO. ACTA ACADEMIAE MEDICINAE SINICAE 1984; 6:326-9. [PMID: 6241081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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3249
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Guo YJ, Yang DR, Wang P, Wang M. [Extraction of the core and matrix proteins and preparation of antisera from type A influenza virus]. ZHONGGUO YI XUE KE XUE YUAN XUE BAO. ACTA ACADEMIAE MEDICINAE SINICAE 1984; 6:381-3. [PMID: 6241095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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3250
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Schaap P, Wang M. The possible involvement of oscillatory cAMP signaling in multicellular morphogenesis of the cellular slime molds. Dev Biol 1984; 105:470-8. [PMID: 6090245 DOI: 10.1016/0012-1606(84)90304-x] [Citation(s) in RCA: 36] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The involvement of pulsatile chemoattractant emission and signal relay in aggregation and multicellular morphogenesis of a variety of cellular slime mold species was investigated. The species differ from each other in the developmental stage when pulsatile signaling first becomes evident. In D. discoideum, D. mucoroides, and D. purpureum pulsatile signal emission starts in the preaggregative field. In D. vinaceo-fuscum, D. mexicanum, P. violaceum, and P. pallidum the aggregation centers shifts from continuous to pulsatile secretion of chemoattractant during the aggregation process. In D. minutum pulsatile signaling starts after the completion of aggregation and slightly before the onset of culmination. Tip formation is a consequence of continued attraction of amoebae inside the aggregate to the center of signal emission. The occurrence of pulsatile signaling at an early stage of development is correlated with the capacity of the tip (signaling center) to organize a relatively large number of cells into a single fruiting body. Several lines of evidence suggest that cAMP is probably involved in the coordination of morphogenetic movement in the multicellular stage of all investigated species.
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