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31.
NC Day PJ Shaw AL McCormack PJ Craig W Smith R Beattie TL Williams SB Ellis PG Ince MM Harpold D Lodge SG Volsen 《Canadian Metallurgical Quarterly》1996,71(4):1013-1024
The distribution of voltage-dependent calcium channel subunits in the central nervous system may provide information about the function of these channels. The present study examined the distribution of three alpha-1 subunits, alpha 1A, alpha 1B and alpha 1E, in the normal human hippocampal formation and parahippocampal gyrus using the techniques of in situ hybridization and immunocytochemistry. All three subunit mRNAs appeared to be similarly localized, with high levels of expression in the dentate granule and CA pyramidal layer. At the protein level, alpha 1A, alpha 1B and alpha 1E subunits were differentially localized. In general, alpha 1A-immunoreactivity was most intense in cell bodies and dendritic processes, including dentate granule cells, CA3 pyramidal cells and entorhinal cortex pre-alpha and pri-alpha cells. The alpha 1B antibody exhibited relatively weak staining of cell bodies but stronger staining of neuropil, especially in certain regions of high synaptic density such as the polymorphic layer of the dentate gyrus and the stratum lucidum and radiatum of the CA regions. The alpha 1E staining pattern shared features in common with both alpha 1A and alpha 1B, with strong immunoreactivity in dentate granule, CA3 pyramidal and entorhinal cortex pri-alpha cells, as well as staining of the CA3 stratum lucidum. These findings suggest regions in which particular subunits may be involved in synaptic communication. For example, comparison of alpha 1B and alpha 1E staining in the CA3 stratum lucidum with calbindin-immuno-reactivity suggested that these two calcium channels subunits may be localized presynaptically in mossy fibre terminals and therefore may be involved in neurotransmitter release from these terminals. 相似文献
32.
J Braungart-Rieker MM Garwood BP Powers PC Notaro 《Canadian Metallurgical Quarterly》1998,34(6):1428-1437
This laboratory study examined mothers' and fathers' sensitivity during face-to-face interactions with their infants as well as infants' affective and regulatory responses during mother-infant versus father-infant still face (SF). The degree to which infant gender and temperament as well as parental sensitivity predicted SF responses was also examined. Participants included 94 healthy, primarily White, middle-class 4-month-olds and their parents. Results indicated that mothers and fathers were equally sensitive toward their infants. Infants' affect and regulatory behaviors were also significantly stable across mother- and father-infant SF situations, although several differences in mean levels of regulation emerged. Finally, the extent to which exogenous and endogenous variables predicted infant SF responses differed as a function of which affect or regulatory variable was being examined and with which parent the infant was experiencing SF. 相似文献
33.
MM Lieber 《Canadian Metallurgical Quarterly》1998,73(6):590-596
Although the general approach to management of a sufficient degree of benign prostatic hyperplasia in the past was surgical intervention (transurethral resection of the prostate), the current availability of effective pharmacologic therapy has changed the initial management strategy. At present, two types of drugs are available for treatment of prostatism: (1) selective alpha-adrenergic blocking agents (terazosin, doxazosin, and tamsulosin) and (2) an inhibitor of the 5 alpha-reductase enzyme (finasteride). Pharmacologic blockade of the alpha(1)-adrenoceptors is thought to result in relaxation of the smooth muscle in the prostate and bladder neck, which reduces urethral resistance, improves voiding function, and minimizes the symptoms of prostatism. These effects may be noted by the patient within several weeks after initiation of treatment. The mechanism of action of finasteride is a blocking of the conversion of testosterone to dihydrotestosterone and an associated volume shrinkage of the prostate. On the average, a 25% reduction in prostate volume can be achieved, but a period of 12 months or longer of finasteride therapy is needed for maximal shrinkage and maximal decrease in symptoms of prostatism. The expanding population of middle-aged and elderly men with prostatism of moderate severity will undoubtedly prompt the development of additional pharmacologic options for treatment of prostatism and benign prostatic hyperplasia. 相似文献
34.
An in-vitro effect of nonapeptide neurohormone vasotocin on thyroid and interrenal glands was studied in hybrid of Siberian and Lena sturgeons [correction of salmons] at light microscopy level using morphometric method. At a concentration of 0.1 and 1 nmol/l vasotocin was shown to exert undirectional stimulating effect on the thyroid and interrenal gland functions. In the presence of vasotocin at a concentration of 1 nmol/l in culture media the activity of glands is even more pronounced than under the influence of adenohypophyseal hormones, adrenocorticotropic (8 x 10 ng/ml) and thyrotropic (5 ng/ml). 相似文献
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A new nucleotide analogue was developed for site-specific incorporation of a reactive thiol group into DNA. This creates a unique site for the post-synthetic modification of that nucleotide with a variety of molecular tags, such as photo-cross-linkers and fluorescent or spin-label moieties. 5'-O-(4,4'-Dimethoxytrityl)-5-[S-(2,4-dinitrophenyl)thio]-2'-deoxyuridin e 3'-O-(2-cyanoethyl N,N'-diisopropylphosphoramidite) was synthesized and incorporated at internal positions in several oligonucleotides using automated DNA synthesis and standard phosphoramidite chemistry. The coupling yield of the analogue was comparable to the coupling yield for a standard phosphoramidite, and no significant differences were observed in the overall yields of the dinitrophenyl-labeled oligonucleotides compared to the corresponding unmodified oligonucleotides. Characterization of the dinitrophenyl-modified oligonucleotides included enzymatic degradation, HPLC chromatography, and gel electrophoresis. Deprotection of the mercaptan group with beta-mercaptoethanol yielded an oligonucleotide containing 5-mercaptodeoxyuridine which was then selectively modified, without purification, by reaction with 5-(iodoacetamido)fluorescein. Incorporation of the dinitrophenyl-modified oligonucleotide into double-stranded DNA was achieved using the polymerase chain reaction. CHaracterization of the dinitrophenyl-labeled product by immunodetection with anti-dinitrophenyl antibodies confirmed the stability of the protecting group to the thermocycling and thus established the use of this thiol-protected mercaptodeoxyuridine phosphoramidite for preparation of site-specifically modified DNA. 相似文献
37.
In Escherichia coli, chi is a recombination hotspot that stimulates RecBCD-dependent exchange at and to one side of itself. chi activity is highest at chi and decreases with distance from chi. The decrease in chi activity may be a simple property of the physical distance over which chi can stimulate recombination. Alternatively, the decay in chi activity with distance may reflect the high likelihood that chi-stimulated recombination occurs in a single chi-proximal act, to the exclusion of additional chi-stimulated exchanges more distal to chi. To test the models, we determined if chi activity decreases as a function of physical distance (i.e., DNA base pairs) or genetic distance (homologous DNA base pairs). Our results indicate that chi activity decays as a function of genetic distance. In addition, we found that the sbcB gene product (exonuclease I, a 3'-->5' ssDNA exonuclease) modulates the distance over which chi can act. In contrast, the recJ gene product (a 5'-->3' ssDNA exonuclease) does not alter the decay of chi activity. 相似文献
38.
OBJECTIVE: To examine the relative contribution of psychologic factors and physical symptoms to the variance in fatigue in older women with heart failure. METHODS: Eighty women who had been hospitalized in the previous 12 months for heart failure were interviewed. Fifty-seven women completed second interviews 18 months after the first interview. RESULTS: Fatigue was the most frequently occurring physical symptom at both measurement times, and it significantly increased with time. Other physical symptoms contributed uniquely to the variance in fatigue at both measurement times, but psychologic factors did not. At time 1, sleep difficulties, chest pain, and weakness each explained unique variance in fatigue. At time 2, dyspnea was the only variable that explained unique variance in fatigue (9%). Dyspnea also explained a significant portion of the variance (7%) in time 2 fatigue, when time 1 fatigue was controlled. CONCLUSIONS: Fatigue in older women with heart failure is related more to other physical symptoms than psychologic factors. 相似文献
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This study was designed to: (a) identify the perceptions of retirees about changes in their life patterns during retirement; (b) investigate the kinds of adjustment problems occurring in retirement as a basis for developing prevention oriented pre-retirement programs; and (c) identify extant factors which could demonstrate underlying themes relating to retirement adjustment. A 72-item, multiple response questionnaire was used to gather demographic data, information on use of time, pre-retirement planning, health problems, changing life patterns, and adjustment to retirement. It is the latter which is reported in these findings. The population included 1565 retirees from a designated company living in the south-eastern United States of America, with a response of 764 subjects (48.82%). Findings suggest the respondents were generally healthy and well adjusted; however, numerous adjustment problem areas were identified within the six life patterns. Additional factor analysis (principal components) demonstrated four factors of particular importance: satisfaction with retirement, retirement concerns, spousal relationships, and pre-retirement preparation outcomes. 相似文献