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991.
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The anatrophic nephrolithomty procedure described by Smith and Boyce is a safe, effective method to remove dendritic renal calculi. Two major departures from their surgical technique have simplified the procedure in our hands. Our experience with 56 consecutive cases treated with the simplified technique is reported.  相似文献   
996.
A neuropathological examination was made of 15 cats anesthetized with alpha-chloralose, subjected to a stepwise reduction in mean arterial pressure by graded hemorrhagic hypotension. Five animals were sacrificed by perfusion-fixation at a mean arterial pressure of 75 mm Hg, 5 at a mean pressure of 35 mm Hg and 5 at 25 mm Hg. Ischemic brain damage was seen in only 5 animals, one sacrificed at a mean arterial pressure of 35 mm Hg and 4 at a pressure of 25 mm Hg. It was maximal in the selectively vulnerable areas and included the boundary zones between the major arteries of the cerebral hemispheres, the Ammon's horn and the thalamus.  相似文献   
997.
Two migrant farm labor camps were observed during two summer harvesting seasons. A part of the observations consisted of interviews with 104 farm laborers, with 16 of them being interviewed intensively. Migrant farm workers were exploited by the crew boss and the farm owner, and they in turn exploited each other. Consequently, many workers left farm work. Those who remained in the camps adapted their attitudes and their views to the conditions. Though they had a begrudging respect for the crew boss, they showed an overriding concern with exploitation. They conveyed a numbness about life, themselves, and their place in society; this numbness was combined with self-criticism and an attempt to maintain some self-respect. They expressed distrust for and suspicion of others, and though they could not articulate it very well, they felt great fear and anxiety. In order to diagnose and treat disorder in migrant farm workers, psychiatrists must understand the exploitive social setting of migrant farm work and the adaptations of workers to that setting.  相似文献   
998.
Seventy-five patients with hemoptysis were treated with bronchial artery embolization (BAE). The procedure was performed with Hexabrix (sodium methylglucamine ioxaglate), Mikaelson catheters, and Gelfoam particles. Angiographic evaluation of the bronchial artery anatomy revealed ten different configurations, which are described. The embolization attempt failed in three cases (4%); eight additional patients (10.7%) were excluded from the series because of inadequate data. In the remaining 64 patients, 41 underwent BAE alone and 23 underwent either chemotherapy or surgery in addition to embolization. Immediate control of hemoptysis was achieved in 49 of 64 patients (76.6%). Long-term control of hemoptysis was achieved in 46 of the 56 patients included in the long-term follow-up (82.1%). Eight of the 64 patients were lost to follow-up, which ranged from one to 47 months (mean 24.8 months). Hemoptysis recurred in 12 of 56 patients (severe in 10, mild in 2) (21.4%). Twelve patients died (21.4%), five of them due to hemoptysis (8.9%). None of the patients who died of hemoptysis had responded to initial BAE. It is concluded that BAE is an effective treatment for immediate control of life-threatening hemoptysis, allowing long-term control of bleeding in the majority of patients.  相似文献   
999.
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The ratio (expressed in log10 units) of the equieffective concentrations of (+)- and (-)-noradrenaline has been measured in a variety of isolated tissues in the presence of cocaine (1 x 10(-5) M), tropolone (3 x 10(-5) M) and (+/-)-propranolol (5 x 10(-7) to 5 x 10(-5) M). The values obtained fall into 3 distinct and statistically different groups. Firstly, a high group comprising (mean +/- s.e.) mouse vasdeferens (2-78 +/- 0-04), rabbit duodenum (2-91 +/- 0-07) and ileum (2-86 +/- 0-05). Secondly a middle group comprising rabbit vas deferens (2-54 +/- 0-04), bladder neck muscle (2-56 +/- 0-07) and spleen 2-50 +/- 0-02), guinea-pig vas deferens (2-55 +/- 0-10) and bladder neck muscle (2-48 +/- 0-13) and rat deferens (2-40 +/- 0-08) and thirdlya low group comprising the bladder detrusor muscle from both the rabbit (2-08 +/- 0-08) and the guinea-pig (2-07 +/- 0-04). Under the same conditions measurement of pA2 values for phentolamine and piperoxan against noradrenaline gave the following values in rat vase deferens (8-22 +/- 0-07 and 6-72 +/- 0-03 respectively) and mouse vas deferens (8-31 +/- 0-05 and 6-53 +/- 0-07 respectively). The results are discussed in relation to other findings conderning the nature of the alpha-adrenoreceptor in these tissues. In spite of the absence of any significant difference between the potency of the alpha-adrenoreceptor blocking agents in the two species it is suggested that alpha-adernoreceptors may not belong to a single homogenous population but may vary in their characteristics from tissue to tissue.  相似文献   
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