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The study was aimed at finding out the influence exerted by the genital afferents on the medial preoptic area (mPOA), which plays a pivotal role in the regulation of male sex behavior. To fulfil this objective, the effects of stimulation of the dorsal penile nerve (DPN) on the activity of 82 mPOA neurons were studied. The base line firing rates of the mPOA neurons, studied by extracellular recording, ranged between 0.5 and 38.5 Hz (mean 7.18 +/- 7.91). The stimulation of the DPN (20 Hz, 0.4 msec. 70 microA) influenced 79.69% of the neurons studied. Though increased firing was the predominant influence produced (50%), decreased firing was also seen in a few (29.69%). The excited and inhibited neurons were randomly distributed within the mPOA. Neurons located in the lateral and posterior hypothalamus were not affected by the DPN stimulation. The stimulation parameters used in this study did not produce any change in the systemic arterial pressure and heart rate. The results provide electrophysiological evidence of afferent inputs from the male sex organ to the mPOA, which is an important area controlling male sex behavior.  相似文献   
73.
There have been 28 previously reported cases of neuroblastoma associated with congenital heart disease. Because many of these have been defects of the conotruncal region, it has been proposed that abnormal neural crest cell migration or maturation may be a factor that links these normally disparate pathologic conditions. Most neuroblastomas in these cases have been detected at autopsy or by radiologic studies conducted in the evaluation of the cardiac anomalies. Recently, we discovered an occult posterior mediastinal neuroblastoma in a patient undergoing a unifocalization procedure for tetralogy of Fallot with pulmonary atresia and major aortopulmonary collaterals. The tumor was resected, and the patient has demonstrated no evidence of residual or metastatic neuroblastoma.  相似文献   
74.
A procedure has been developed for determining the concentrations of superoxide anion radical (SOAR) in aprotonic fluids by using semiconductor chemical sensors. SOAR life in pure solutions is 6.3 hours. Supplements of biological fluids (blood, urine, plasma) increase the rate of SOAR death. There is a great difference in the reaction rate of SOAR with biological fluids in apparently healthy and ill individuals. It is suggested that the above procedure opens vistas both for studies of vital activity and for diagnosis of abnormalities.  相似文献   
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In the gynecological department of Rostov Oncological Institute endolymphatic polychemotherapy with a preliminary determination of tumor sensitivity to chemotherapy was employed in 54 patients with cervical cancer, 3 of them in stage III and IV having contraindications to radiotherapy. A combination of chemical substances and the dosage of single administration were as follows: thio-TEPA--100--150 mg + methotrexate 75--100 mg; thio-TEPA--100--150 mg + 5-fluoruracil--1000 mg; cyclophosphane--2000 mg + methotrexate--75--100 mg; cyclophosphane--1600 mg + methotrexate--75--100 mg + 5-fluoruracil--750 mg. Lymphoinfusion was made in the lower extremity, and after 7--10 days it was repeated in the second one. Visual disappearance of the tumor was noted in 17 patients, lessening of the tumor size by two-thirds--in 16, a 1/2 decrease--in 20. Among 23 patients in stage III after the treatment parametrial infiltrations disappeared entirely in 11 cases and only in pelvic walls--in 12. In 40 cases an extensive extirpation of the uterus with adnexa was performed. In all cases degenerative changes in tumor tissues were observed, whereas in 7 cases no tumor cells were found.  相似文献   
77.
The author discusses some modern problems concerning the clinical pictures of dementia which have a certain theoretical and practical significance. The paper contains some results related to the dynamics of syndromes in acquired dementia and of the most frequently seen variants in the development of such conditions. The possibility of diagnosing dementia corresponding to the phases of mental disorders are discussed. The dynamics of dementia syndromes are considered from the point of view of their nosological specificity.  相似文献   
78.
Expression of alpha-D-mannosidase in man-hamster somatic cell hybrids   总被引:1,自引:0,他引:1  
Two types of alpha-D-mannosidase isozymes are present in human white blood cells, human diploid fibroblasts, and HeLa cells. One of these (the S isozyme) constitutes the major alpha-D-mannosidase of the human cells, has a pH optimum of 4.4, and is associated with lysosomes. The other (the F isozyme) is most active at pH 6, is acid labile, and is located in the soluble portion of the cytoplasm. The expression of human lysosomal alpha-D-mannosidase was examined in man-hamster hybrid clones, and was found to be concordant with that of phosphohexose isomerase in 54 of 55 primary clones. A locus specifying human lysosomal alpha-D-mannosidase has therfore been assigned to chromosome 19.  相似文献   
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We have shown that 8S and U2 fractions of low molecular weight nuclear RNA lmwn RNA) have tow stable conformational states with different electrophoretic mobilities. We have shown also that fractions UIa and UIb are conformational isomers. Fractions 8S and U2 are present only in one conformational state during electrophoresis, while UI RNA is always represented by both conformations. The conformation of lmwn RNAs is dependent upon conditions of isolation of nuclei and of extraction of RNA. It may change during storage of water solution of RNA at -20 degrees. Conformational changes discovered are not the result of degradation. Only one of two stable conformations of any lmwn RNA may be physiologically active, as it is the case of 5S rRNA and tRNAS. One ought to keep this in mind while studying the functions of low molecular weight nuclear RNAs.  相似文献   
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