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991.
Observations of monkey behavior were made on free-ranging and corral-enclosedMacaca mulatta. Two sampling techniques were used: focal animal and group observations. Group observations measured frequencies of social
behavior whereas focal observations used time samples which estimated durations of social and nonsocial activities as well
as frequencies of social behavior. Analysis of concordance within and between sampling techniques revealed that short duration
focal time samples provide a reliable estimate of total frequencies of social behaviors derived using group observations and
furthermore, allows the recording of important nonsocial activities not easily recorded in terms of frequencies. Focal time
sampling is advantageous for certain types of studies where the equal distribution of observation time between individuals
is important, particularly in the field where visibility is often limited and individuals can only be observed continuously
for short periods of time.
This work was supported by grants from the H. F. Guggenheim Foundation, Dr.H. C. Robinson, Jr., and USPHS grants MH 24607 and MH 25642. 相似文献
992.
Naohide Yamamoto John W. Philbeck Adam J. Woods Daniel A. Gajewski Joeanna C. Arthur Samuel J. Potolicchio Jr Lucien Levy Anthony J. Caputy 《PloS one》2014,9(5)
Path integration is a process in which observers derive their location by integrating self-motion signals along their locomotion trajectory. Although the medial temporal lobe (MTL) is thought to take part in path integration, the scope of its role for path integration remains unclear. To address this issue, we administered a variety of tasks involving path integration and other related processes to a group of neurosurgical patients whose MTL was unilaterally resected as therapy for epilepsy. These patients were unimpaired relative to neurologically intact controls in many tasks that required integration of various kinds of sensory self-motion information. However, the same patients (especially those who had lesions in the right hemisphere) walked farther than the controls when attempting to walk without vision to a previewed target. Importantly, this task was unique in our test battery in that it allowed participants to form a mental representation of the target location and anticipate their upcoming walking trajectory before they began moving. Thus, these results put forth a new idea that the role of MTL structures for human path integration may stem from their participation in predicting the consequences of one''s locomotor actions. The strengths of this new theoretical viewpoint are discussed. 相似文献
993.
The effect of a variety of structurally diverse antibiotics on C55-isoprenoid-alcohol kinase (EC 2.7.1.66) from Staphylococcus aureus has been examined. Only moenomycin was found to be inhibitory (Ki = 0.2 mM).Moenocinol, The C25 lipid component of moenomycin, did not serve as a substrate of kinase reaction and was less inhibitory than the intact antibiotic.It is concluded that the observed inhibition may be due to the structural similarity between C55-isoprenylmonophosphate and the substituted moenocinol moiety of moenomycin. 相似文献
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M. C. McClellan M. A. Diekman J. H. Abel Jr. Dr. G. D. Niswender 《Cell and tissue research》1975,164(3):291-307
The development of granulosa-lutein cells was studied in 27 normal and 32 superovulated ewes between days 0-4(day 0 began with the preovulatory LH peak in normal animals and the HCG injection in superovulated ewes). The pattern of differentiation was similar in both groups. Following initial hormonal stimulation (0-12 hours after LH or HCG), granulosa cells were approximately 100 mu2 and contained small, pleomorphic nuclei with large amounts of clumped chromatin. Elongate cells lining the basement membrane possessed large, heterogeneous dense bodies, and a well-developed Golgi apparatus. Mitotic figures were observed up to 6 hours prior to ovulation. Sixteen to 20 hours following the LH surge or HCG injection, hypertrophy of granulosa cells was evident. Nuclei contained definitive nucleoli. Blood vessels in the theca interna were abundant and highly dilated. Ovulation occurred approximately 24 hours after the LH peak or HCG injection. Visible signs of luteinization were evident 6-12 hours after ovulation. A slight increase in serum progesterone levels was detected. The second post-ovulatory day was characterized by continuing hypertrophy of granulosa cells and extensive proliferation of smooth endoplasmic reticulum and mitochondria. Nuclei of granulosa cells were larger and possessed extremely large nucleoli. Numerous mitotic figures were apparent within the corpus luteum. Serum progesterone concentrations began increasing at 60-72 hours after hormone stimulation. By the end of the third post-ovulatory day, the corpus luteum consisted of large, pleomorphic, parenchymal cells, interspersed between capillaries and connective tissue elements. Only an occasional mitotic figure was apparent within the corpus luteum at 100 hours. Light microscopic autoradiography of 5, 10, and 15 day corpora lutea taken from ewes pulsed with 3H thymidine at specific times before and after ovulation revealed that granulosa cells did not undergo secondary mitoses following ovulation. In contrast, thecal, mesenchymal and endothelial cells did mitose on day 3. 相似文献
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999.
A micro method for simultaneous determination of galactosyltransferase and 5''-nucleotidase activities in cell fractions. 下载免费PDF全文
Galactosyltransferase and 5'-nucleotidase were assayed in the same reaction mixture, with ovalbumin as exogenous acceptor of (14-C)galactose and with (3-H)AMP as the substrate for the 5'-nucleotidase assay. The substrates and reaction products of either assay had no significant effect on the activity of the other enzyme. 相似文献
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