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Haaga  JR; Beale  SM 《Radiology》1986,161(3):829-830
By injecting small amounts of CO2 through a needle, one can move bowel or bladder from the intended path of instruments during interventional procedures. The technique worked well in six of seven cases in the pelvis and retroperitoneum; it was not effective in the mediastinum or midabdomen (n = 6).  相似文献   
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A binding site for tritiated 2-amino-6, 7-dihydroxy-1, 2,3,4-tetrahydronaphthalene (ADTN) has been partially characterized in the rabbit iris root-ciliary body. Binding of ADTN is proportional to protein content and requires at least 60 minutes to reach equilibrium. Binding is saturable, with a Kd of 27 +/- 1 nM and a Bmax of 2.1 +/- .3 pmol/mg protein (mean +/- SEM). Dopamine competes for this site with a Ki of 100 nM and apomorphine with a Ki of 180 nM. This site is not blocked by L-timolol, phenoxybenzamine, or by several DA1 and DA2 antagonists. It appears to be a new type of catecholamine binding site, of a type not observed outside the anterior eye. It is possible that some of the effects of dopamine on intraocular pressure are mediated through this binding site.  相似文献   
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PURPOSE: Flavonoids with two to five hydroxy groups, with or without sugar, and/or methoxy groups were studied on their effects to affect ocular blood flow. METHODS: Colored microsphere technique was used to determine the ocular blood flow in rabbit eyes. RESULTS: Flavonoids with three free hydroxy (OH) groups seemed to produce the optimal effects in increasing ocular blood flow (naringenin and hesperitin, Pfalts and Bauer, Waterbury, CT). Whether the OH groups are below three (naringenin, hesperitin, Pfalts and Bauer, Waterbury, CT) or above four (Quercetin, Pfalts and Bauer, Waterbury, CT), they produced no effects on the ocular blood flow. When OH groups are four (rutin, Aldrich, Milwaukee, WI), it produced mixed effects on ocular blood flow. The attachment of rutinose and/or methoxy group in the structure did not affect the ocular blood flow one way or the other. CONCLUSION: The ocular blood flow is increased significantly by the number of OH group in the molecule, with three the best to increase the ocular blood flow.  相似文献   
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Background. This study is intended to determine the causes of pediatric traumatic brain injuries (PTBI) in children aged 14 years or less, and to identify various types of craniocerebral damage resulting from different mechanisms of injury.Methods. From July 1, 1993 to June 30, 2001, a survey on PTBI was conducted in Taiwan. The data of patients used in this study were collected from 56 major hospitals among the age group of 0-14 years. The items in the traumatic brain injury survey included sex, age, causes of injuries, severity, and the eventual outcome.Results. A total of 5349 cases were identified. The male-to-female ratio was 1.69: 1. The incidence rate was higher in the age groups of 4-9 years and 10-14 years. The main cause of PTBI was traffic injury, which accounted for 2537 of the cases (47.3%), followed by falls, 2160 (40.3%). Of all traffic injuries, motorcycle-related injury had the highest incidence, followed by the pedestrian and bicycle-related injury. This study also showed that 83.2% of the patients had mild injury, 9.8% had moderate injury, and 7.0%, severe injury.Conclusions. The results of this study suggest that it is important to decrease all the risk factors in the environment of homes and public areas as much as possible. Helmet wearing and the development of public transportation are essential for the prevention of head injury.  相似文献   
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Epinephrine (1, 3 and 10 micrograms/kg) was found to increase retinal and choroidal blood flow (22, 49 and 67%) when it was administered intravenously. The increase in retinal and choroidal blood flow coincided well with the increase in systemic blood pressure (44, 65 and 96%, respectively). When epinephrine (2%) was instilled to the eyes topically the retinal and choroidal blood flow decreased (15%) while systemic blood pressure remained unchanged. It is suggested that the decrease in retinal and choroidal blood flow by topical epinephrine could be the cause of epinephrine maculopathy reported previously. L-Timolol (0.25%, topically) did not affect retinal and choroidal blood flow significantly.  相似文献   
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外科医生和手术室人员经常接触手术设备产生的烟气,病人也会暴露于烟气中,特别是腹腔镜手术中产生的烟气滞留于腹腔内这一密闭空间并被吸收.这些烟气是一种与香烟烟气相似的毒性物质,然而对这种毒性物质的影响还未引起足够重视.应该采取必要措施尽可能减少手术中烟气的不良影响.  相似文献   
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