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71.
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The projections of enteric neurons to the circular muscle of the guinea pig gastric corpus were investigated systematically by using the retrogradely transported fluorescent carbocyanine dye 1,1'-didodecyl-3,3,3',3'-tetramethyl indocarbocyanine perchlorate (DiI), applied to the muscle layer or myenteric plexus in vitro. DiI-labeled motor neuron cell bodies were located up to 6.3 mm aboral, 17 mm oral, and up to 20 mm circumferential to the DiI application site. Labeled nerve fibers ran for long distances from the DiI application site toward the greater and lesser curvatures, where they coursed parallel to the bundles of the "gastric sling" muscle. The majority of labeled cells were located toward the lesser curvature of the stomach. Nerve cell bodies that were aboral to the DiI application site were usually small, immunoreactive for choline acetyltransferase, and, thus, were likely to be excitatory motor neurons. Neurons that were located orally were larger, fewer in number, and immunoreactive for nitric oxide synthase and, thus, were likely to be inhibitory motor neurons. Application of DiI directly to the myenteric plexus filled neurons up to 15 mm aborally and up to 21 mm orally but labeled few neurons circumferentially. All nerve cells that were filled from either the circular muscle or the myenteric plexus had Dogiel type I morphological features. These results demonstrate a clear polarity of projection of inhibitory and excitatory motor neurons and a functionally continuous innervation of the circular and gastric sling muscle layers. Nonmotor neurons in the myenteric plexus were demonstrated, but neurons with Dogiel type II morphological features are apparently absent.  相似文献   
73.
Social media has emerged as a significant and effective means of assisting and endorsing activities and communications among peers, consumers and organizations that outdo the restrictions of time and space. While the previous studies acknowledge the role of agents of culture change, it largely remains silent on the role of social media in influencing acculturation outcomes and consumption choices. This study uses self-administered questionnaire to collect data from 514 Turkish-Dutch respondents and examines how their use of social media affects their acculturation and consumption choices. This research makes a significant contribution to consumer acculturation research by showing that social media is a vital means of culture change and a driver of acculturation strategies and consumption choices. This study is the first to investigate the role of social media as an agent of culture change in terms of how it impacts acculturation and consumption. The paper discusses implications for theory development and for practice.  相似文献   
74.
A precise alignment between point-to-point free space optical (FSO) networks is crucial in order to maximize the performance of data transmission. A sway or low-frequency vibration of FSO base station can affect line-of-sight quality and hence may lead to the occurrence of higher BER. Therefore, the work presented in this paper is to demonstrate an improved auto-alignment single-channel FSO transmission system at X-axis detection area. The receiver base station was fed with pulsed signal laser from a tunable laser source with a central wavelength of 1550 nm. The detection mechanism responds from an analog input signal received that corresponds to the X-axis direction of transmitter vibration. The detection performance of the system was observed by using two approaches: auto-searching of artificial intelligence (AI) detection with stop command and without stop command. The obtained results indicate that the bit sequence of the pulsed signal has low loss by implementing the auto-searching of AI detection with stop command features and hence improves the efficiency of the overall FSO transmission system.  相似文献   
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Focal proliferation of smooth muscle cell (SMC) is an integral part of atherosclerotic plaque formation: characterization of regional variation in SMC growth kinetics is therefore important to the understanding of atherogenesis. SMC growth kinetics of rabbit abdominal and thoracic segments were compared. Rabbit aortas were denuded of endothelium and the animals killed after 3H-thymidine and Evans blue injections at 0 to 48 days after denudation. Incorporation of 3H-thymidine into both aortic segments peaked at 48 hours; no detectable incorporation occurred in the first 24 hours. Abdominal segment DNA specific activity (SA, dpm/micrograms DNA) and total kinetic activity (TKA, dpm/0.1 mm internal elastic lamina) at 48 hours were significantly greater than values for the thoracic aorta. Abdominal SA and TKA curves decreased exponentially after the 48-hour peak and parallel thoracic levels after day 7. SA and TKA values for each segment reflected the subsequent SMC intimal growth rates as measured morphometrically. Therefore, both segments share similar growth kinetic characteristics; however, the abdominal response to initimal injury is greater than the thoracic and leads to greater myointimal proliferation. The difference in response to injury in the two segments suggests regional variation in SMC's which are phenotypically similar.  相似文献   
77.
这幢位于瑞士比尔郊区的公寓高三层,由8套大小不同的住宅单元所构成,所处位置能够俯瞰整个小镇,具有极佳的视野。下面的部分是跃层式的二层公寓,上面一层则是普通公寓。楼顶为公共活动区域,设有孩子们的游戏室,其屋顶形式与相邻的建筑风格颇为近似。基地东南向的陡坡非常理想地  相似文献   
78.
The acute intravenous toxicity of tedisamil, a new potassium channel blocker, was assessed by infusing it at various rates (1.5 to 10 mg/kg/min.) to ventilated or spontaneously breathing rats subjected to blockade of their peripheral somatic and autonomic nervous systems. The lethal doses for ventilated rats (including pithed animals) were 2-3 times higher than those for spontaneously breathing animals. In spontaneously breathing rats death appeared to be due to respiratory depression which was possibly of central origin since the lethality of tedisamil was not markedly altered by vagotomy, bilateral carotid artery ligation, nor by autonomic nervous system blockade. On the other hand, in all of the artificially ventilated groups, death occurred at higher doses and was related to direct cardiac actions, possibly involving blockade of cardiac potassium and sodium channels. The cardiovascular responses to infusions of tedisamil included tachyarrhythmias, bradycardia, blood pressure changes, increased QRS width and Q-T interval duration. Arrhythmias occurred at sublethal doses and were eliminated by autonomic blockade and pithing. However, the bradycardia, ECG and blood pressure changes induced by tedisamil infusions were unaltered by the various treatments. Thus tedisamil may induce arrhythmias by actions on the autonomic system.  相似文献   
79.
In Brassica, the recognition of self-related pollen by the stigma is controlled by the highly polymorphic S locus that encodes several linked and coadapted genes and can span several hundred kilobases. We used pulsed-field gel electrophoresis to analyze the structure of different S haplotypes. We show that the S2 and S13 haplotypes of Brassica oleracea contain extensive sequence divergence and rearrangement relative to each other. In contrast, haplotypic configuration is more conserved between B. oleracea S13 and B. campestris S8, two haplotypes that have been proposed to be derived from a common ancestral haplotype based on sequence comparisons. These results support the view that extensive restructuring of the S locus preceded speciation in Brassica. This structural heteromorphism, together with haplotype-specific sequences, may suppress recombination within the S locus complex, potentially providing a mechanism for maintaining the linkage of coadapted allelic combinations of genes over time.  相似文献   
80.
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