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61.
Sulfated cholecystokinin octapeptide (CCK-8) was administered either intraperitoneally or into the cerebral ventricle of fully conscious mice, and locomotor activity was quantified. CCK-8 administered by either route suppressed locomotor activity. Subcutaneously administered selective CCK-A receptor antagonist, L-364,718 (1 mg/kg), reversed the inhibitory effect of centrally as well as peripherally administered CCK-8, but the selective CCK-B receptor antagonist, L-365,260 (1 mg/kg), did not. These results demonstrate that centrally as well as peripherally administered CCK-8 suppresses locomotor activity in mice through an interaction with CCK-A, but not CCK-B, receptors. 相似文献
62.
Benson Okita‐Ouma Rajan Amin Frank Van Langevelde Nigel Leader‐Williams 《African Journal of Ecology》2010,48(3):791-799
Density‐dependent feedback mechanisms provide insights into the population dynamics and interactions of large herbivores with their ecosystem. Sex ratio also has particularly important implications for growth rates of many large mammal populations through its influence on reproductive potential. Therefore, the interrelationships between density‐dependent factors, comprising density, sex ratio and underlying growth rates (r) were examined for the Eastern black rhino (Diceros bicornis michaeli) living in three rhino sanctuaries in Kenya using four population models. The exponential and logistic models gave similar results and the former were accepted because they better portrayed the actual situation on the ground. Sex ratios in all sanctuary populations were positively correlated with r but interpreted with realization of other factors also affecting r. We caution that the results of population models should be interpreted alongside ground‐truthed observations. We recommend that future translocation strategies should take into account sex and age structures of the donor population, while future studies of density dependence should take into account both biotic and abiotic factors. 相似文献
63.
Control of ventilation in extreme-altitude climbers 总被引:4,自引:0,他引:4
Masuyama S.; Kimura H.; Sugita T.; Kuriyama T.; Tatsumi K.; Kunitomo F.; Okita S.; Tojima H.; Yuguchi Y.; Watanabe S.; et al. 《Journal of applied physiology》1986,61(2):500-506
Ten climbers who participated in the Nepal-Japan Kangchenjunga Expedition (altitude, 8,478-8,586 m) in 1984 were examined for their hypercapnic and isocapnic hypoxic ventilatory responses (HCVR and HVR) at sea level before and after the expedition. Five climbers who reached an altitude higher than 8,000 m, [designated high-performance climbers (HPC)] exhibited significantly higher HVR than five climbers who did not [low-performance climbers (LPC)]. On the other hand, no significant difference in HCVR was seen between HPC and LPC. Our results were in agreement with the findings reported by Schoene et al. (J. Appl. Physiol. 56: 1478-1483, 1984) obtained in the American Medical Research Expedition to Everest in 1981. Significant depression in HVR in five climbers was found even 35-40 days after the expedition, which was accompanied by decreased arterial partial pressure of CO2 and increased pH at rest. Hence, the effect of altitude acclimatization in the climbers exposed to extreme altitude may have still persisted at the time of the postexpedition study. Our results confirmed that HRV evaluated at sea level may be used as an indicator of a climber's capability at great high altitude. 相似文献
64.
Ethical Obligations in the Face of Dilemmas Concerning Patient Privacy and Public Interests: The Sasebo Schoolgirl Murder Case 下载免费PDF全文
A murder case that had some features in common with the Tarasoff case occurred in Sasebo City, Japan, in 2014. A 15‐year‐old high school girl was murdered and her 16‐year‐old classmate was arrested on suspicion of homicide. One and a half months before the murder, a psychiatrist who had been examining the girl called a prefectural child consultation centre to warn that she might commit murder, but he did not reveal her name, considering it his professional duty to keep it confidential. Article 134 of the Japanese Criminal Law states that doctors should not disclose patient information obtained in clinical practice without a legitimate reason, but the Japanese Supreme Court has not specified what constitutes a legitimate reason. Mass media and commentators suggested that the murder could have been prevented if the psychiatrist had disclosed the girl's name to the authorities or had isolated her coercively in a psychiatric ward. However, the authors disagree with such claims. This article discusses obligations imposed on concerned individuals and third party members in cases involving ethical dilemmas regarding patient confidentiality and information disclosure. It is concluded that everyone should fulfill their obligations to prevent such tragedies and one should judge the appropriateness of others’ actions based not on the consequences of their actions, but on the processes used to decide on a course of action and their commitment. It is necessary for us to establish a society in which concerned parties can do what they think is ethically best without fearing ungrounded charges. 相似文献
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67.
Microsatellite polymorphism in the human heme oxygenase-1 gene promoter and its application in association studies with Alzheimer and Parkinson disease 总被引:16,自引:0,他引:16
Teiko Kimpara A. Takeda Koichi Watanabe Yasuto Itoyama Shuntaro Ikawa Minro Watanabe Hiroyuki Arai Hidetada Sasaki Susumu Higuchi Naoshi Okita Sadao Takase Hiroshi Saito Kazuhiro Takahashi Shigeki Shibahara 《Human genetics》1997,100(1):145-147
Oxidative stress has been suggested to be involved in the pathogenesis of neurodegenerative diseases, such as Alzheimer disease
(AD) and Parkinson disease (PD). Heme oxygenase-1 (HO-1), a key enzyme in heme catabolism, also functions as an antioxidant
enzyme. Here, we show that a (GT)n repeat in the human HO-1 gene promoter region is highly polymorphic, although no particular alleles are associated with AD
or PD. This newly identified genetic marker should allow us to study the possible involvement of HO-1 in certain human diseases.
Received: 5 November 1996 / Accepted: 18 February 1997 相似文献
68.
Formation of wheat protein bodies: Involvement of the Golgi apparatus in gliadin transport 总被引:1,自引:0,他引:1
Developing wheat (Triticum aestivum L.) endosperm was examined using ultrathin sections prepared from tissues harvested at 5, 9, 16 and 25 d after flowering. Protein bodies were evident by 9 d and displayed a variety of membranous structures and inclusions. The Golgi apparatus was a prominent organelle at all stages, and by 9 d was associated with small electron-dense inclusions. By immunocytochemical techniques, gliadin (wheat prolamine) was localized within these vesicles and in homogeneous regions of protein bodies, but not in the lumen of the rough endoplasmic reticulum. The protein bodies appear to enlarge by fusion of smaller protein bodies resulting in larger, irregular-shaped organelles. The affinity of the Golgi-derived vesicles for gliadin-specific probes during the period of maximal storage-protein synthesis and deposition indicates that this organelle includes the bulk, if not all, of the gliadin produced. The involvement of the Golgi apparatus in the packaging of gliadins into protein bodies indicates a pathway which differs from the mode of prolamine deposition in other cereals such as maize, rice and sorghum, and resembles the mechanism employed for the storage of rice glutelin and legume globulins.Abbreviations ER
endoplasmic reticulum
- IgG
immunoglobulin G
- DAF
days after flowering 相似文献
69.
ADPglucose pyrophosphorylase has been extensively purified from potato (Solanum tuberosum L.) tuber tissue to study its structure. By employing a modified published procedure (JR Sowokinos, J Preiss [1982] Plant Physiol 69: 1459-1466) together with Mono Q chromatography, a near homogeneous enzyme preparation was obtained with substantial improvement in enzyme yield and specific activity. In single dimensional sodium dodecyl sulfate polyacrylamide gels, the enzyme migrated as a single polypeptide band with a mobility of about 50,000 daltons. Analysis by two-dimensional polyacrylamide gel electrophoresis, however, revealed the presence of two types of subunits which could be distinguished by their slight differences in net charge and molecular weight. The smaller potato tuber subunit was recognized by antiserum prepared against the smaller spinach leaf 51 kilodalton ADPglucose pyrophosphorylase subunit. In contrast, the anti-54 kilodalton raised against the spinach leaf subunit did not significantly react to the tuber enzyme subunits. The results are consistent with the hypothesis that the potato tuber ADPglucose pyrophosphorylase is not composed of a simple homotetramer as previously suggested, but is a product of two separate and distinct subunits as observed for the spinach leaf and maize enzymes. 相似文献
70.
Comparison of the primary sequences of two potato tuber ADP-glucose pyrophosphorylase subunits 总被引:1,自引:0,他引:1
Paul A. Nakata Thomas W. Greene Joseph M. Anderson Brian J. Smith-White Thomas W. Okita Jack Preiss 《Plant molecular biology》1991,17(5):1089-1093
Near-full-length cDNA clones to the small and large subunit of the heterotetrameric potato tuber ADP-glucose pyrophosphorylase have been isolated and characterized. The missing amino terminal sequence of the small subunit has also been elucidated from its corresponding genomic clone. Primary sequence comparisons revealed that each potato subunit had less identity to each other than to their homologous subunit from other plants. It also appeared that the smaller subunit is more conserved among the different plants and the larger subunit more divergent. Amino acid comparisons of both potato tuber sequences to theEscherichia coli ADP-glucose pyrophosphorylase sequence revealed conserved regions important for both catalytic and allosteric function of the bacterial enzyme. 相似文献