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991.
992.
The decision for nonoperative treatment of abdominal stab wounds is usually based on clinical examination findings. It is important, however, to identify patients who may suffer occult injuries and, therefore, be benefited from further diagnostic evaluation. Isolated penetrating gallbladder injuries may produce minimal symptoms initially. A high index of suspicion and appropriate selection of imaging studies may lead to early identification. Hepato-iminodiacetic acid scan can be used as the definitive diagnostic imaging test in such occasions. 相似文献
993.
Unauthorized immigrants arriving in Western countries increasingly are being subjected to stringent restrictions while their residency claims are assessed. The present study was a investigation of premigration exposure to organized violence and postmigration stressors in 40 individuals seeking asylum who were attending a community welfare center in Sydney, Australia. Almost 80% reported exposure to premigration trauma such as witnessing murders, having their lives threatened, being separated from family members, and brainwashing; 25% had been tortured. Asylum seekers reported a marked decline in socioeconomic status. Common ongoing sources of severe stress included fears of being repatriated, barriers to work and social services, separation from family, and issues related to the process of pursuing refugee claims. More than one third had problems obtaining health services in Australia--the same number who reported similar difficulties in their home countries. Although based on a selective and culturally heterogeneous sample, the results suggest that salient aspects of the asylum-seeking process may compound the stressors suffered by an already traumatized group. 相似文献
994.
Tarsiers and extinct tarsier-like primates have played a central role in views of primate phylogeny and evolution for more than a century. Because of the importance of tarsiers in so many primatological problems, there has been particular interest in questions about the origin of tarsier specializations and the biogeography of early tarsioid radiations. We report on a new fossil of rare Afrotarsius that shows near identity to modern Tarsius in unique specializations of the leg, which provides information about the locomotor behavior and clarifies the phylogenetic position of this previously controversial primate. These specializations constitute evidence that Afrotarsius is a tarsiid, closely related to extant Tarsius; hence, it is now excluded from being a generalized sister taxon to Anthropoidea. 相似文献
995.
996.
GC Vitale 《Canadian Metallurgical Quarterly》1997,173(1):21-5; discussion 26
997.
Although activation of one seven-transmembrane receptor can influence the response of a separate seven-transmembrane receptor, e. g., the phenomenon of synergism, the underlying mechanism(s) for this signaling process is unclear. The present study investigated communication between two receptors that exhibit classical synergism, e.g., human platelet thrombin and thromboxane A2 receptors. Activation of thrombin receptors caused an increase in ligand affinity of thromboxane A2 receptors. This effect (i) was shown to be specific, since a similar increase in ligand affinity was not caused by ADP or A23187; (ii) did not require cytosolic components, e.g., kinases, proteases, phosphatases, etc., because it occurred in isolated platelet membranes; (iii) was G protein-mediated because it was blocked by an Galphaq C terminus antibody; and (iv) was associated with a net increase in Galphaq coupling to thromboxane A2 receptors. Collectively, these data provide evidence that seven-transmembrane receptors that share a common Galpha subunit can communicate with each other via a redistribution of their G proteins. Thus, activation of thrombin receptors increases Galphaq association with thromboxane A2 receptors thereby shifting them to a higher affinity state. This signaling phenomenon, which modulates receptor-ligand affinity, may serve as a molecular mechanism for cellular adaptive processes such as synergism. 相似文献
998.
Narratives of sexual abuse are always social constructions. They are shaped by developmental and relational factors, as well as by historical events. Because psychodynamic therapy places highest value on subjective, inner truth, it is poorly adapted to the task of determining "historical" truth as required by the legal system. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
999.
1000.
S Birch A Gafni B Markham M Marriott D Lewis P Main 《Canadian Metallurgical Quarterly》1998,15(4):233-242
Of the 7,713 subjects aged 50 and over in a multistage random sampling national survey of Thailand, 4,480 Thai elders aged 60 and over were interviewed in a study which aimed to determine rate, characteristics and the associated factors of falls in the last six months. Eight hundred and thirty-six elders (18.7%) had one or more falls. Female elders (21.5%) fell more often than their male counterparts (14.4%). There was no association between age and falls among Thai elder population. Most of the falls occurred outside (65%) and during the day time (85%). Multiple regression analysis showed that independent factors associated with falls among male elder were a bad or fairly bad health, reported hypertension, problems with walking in the house, problems with crouching and a lack of electricity in the house. Independent factors associated with falls among female elders were a bad or fairly bad health, joint problems, illness which made her unable to have normal activities during the last year, problems with crouching, going to buy food everyday, very lonely feeling, having less than 3 meals a day, a lack of electricity in the house and living in a Thai style house or hut. This study revealed that environmental and intrinsic health factors which affected balance and gait were the main factors associated with falls among Thai elders. Nutritional status as a contributing factor to falling among elderly women was also suggested. 相似文献