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71.
Fifty-two patients with radiation enteropathy secondary to radiation for abdominal or pelvic malignant neoplasms are described. This series (1977 to 1984) is compared with a series of 50 patients from the same institution over an earlier period (1961 to 1977). Intestinal obstruction was the principal complication in both series; 96% of the patients underwent either intestinal resection or anastomotic bypass of the affected segment. Changes that have occurred since the last report are as follows: changes in source of radiation energy (linear accelerator); less evidence of mucosal damage; increased serosal reaction ("serosal peel"); and increased use of elemental diets, parenteral nutrition, and long intestinal tubes in surgical management. Since postoperative radiation injury occurs most frequently in the pelvis, new developments for the exclusion of small bowel from the pelvis during radiation are reviewed. Changes in fractionation of radiation dosage should also be considered in patients with enteric symptoms during radiation therapy.  相似文献   
72.
"Jelly-bump" deposits, which are composed mainly of lipids, on high water content, extended-wear hydrogel lenses, are a clinically significant problem of unknown etiology. The authors explored the effect of nutrition on the frequency of deposition of these jelly bumps. Forty-three patients were included in this masked case-control study from five contact lens practices in North America. Thirty patients were lipid-depositor cases and 13 were controls. Tear specimens were drawn and analyzed for potassium by atomic-absorption spectrophotometry. Detailed dietary histories were conducted and diet nutrient composition was computed. Patients with diminished tear-potassium concentrations have an increased risk of jelly-bump deposition. Elevated intake of protein, alcohol, and cholesterol also appeared to be correlated significantly with increased jelly-bump deposition. The authors found that diabetics and the use of diuretics, anticholinergics, sympathomimetics, were associated with tear-film potassium depletion and lipid deposit formation.  相似文献   
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75.
Torque and antitorque running sutures as described by Eisner are commonly used in penetrating keratoplasty. We tested the rotational effect of three different 16-bite running suture patterns on eight cadaver eyes, with the following results: (1) the torque pattern rotates the corneal graft counterclockwise by 0.7 +/- 0.1 mm at the wound or 11 degrees; (2) the antitorque pattern rotates the corneal graft clockwise by 0.7 +/- 0.1 mm at the wound or 11 degrees; (3) an intermediate "no torque" pattern, the bites of which form an isosceles triangle, produces no rotational effect. We recommend the use of a "no torque" pattern to minimize corneal graft rotation.  相似文献   
76.
R W Hart 《Neurotoxicology》1990,11(2):181-187
The global marketplace is changing rapidly. Never in history has the opportunity to capture new markets with new products and new generations of products been greater. However, never has the chance of losing established markets been higher. We are failing to develop new products despite the fact that Americans have paid for the science from which the world's new technologies were developed. There are many reasons for our failure to turn scientific leads into products. One of the most obvious is that we overestimate the risk of new technologies. Present policy uses a conservatively biased risk assessment process to estimate risk. This process uses many assumptions to bridge gaps in our scientific knowledge about risk. If we wish to be competitive, we must bring safe, inexpensive new products to the marketplace faster. We must seek ways of making our policies more effective while still protecting public health. Risk assessment sets the standards for product development, product approval, and environmental release. A slight miscalculation in "safety levels" can result in tens of billions of dollars in cost added to products. These added costs have a major and direct impact on the competitiveness of U.S. products in the global marketplace where differences in consumer acceptance can be calculated in a few percentage points difference in price.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
77.
Summary The anti-inflammatory activity of hamamelis distillate has been evaluated with respect to drug concentration (0.64 mg/2.56 mg hamamelis ketone/100 g) and the effect of the vehicle (O/W emulsion with/without phosphatidylcholine (PC) in an experimental study. The effects were compared with those of chamomile cream, hydrocortisone 1% cream and 4 base preparations. Erythema was induced by UV irradiation and cellophane tape stripping of the horny layer in 24 healthy subjects per test. Skin blanching was quantified by visual scoring and chromametry. Drug effects were compared with one another and with an untreated control area, as well as with any action due to the vehicle.UV-induced erythema at 24 h was suppressed by low dose hamamelis PC-cream and hydrocortisone cream. Hydrocortisone appeared superior to both hamamelis vehicles, hamamelis cream (without PC) and chamomile cream. The latter preparation was also less potent than hamamelis PC-cream. Erythema 4 to 8 h after the stripping of the horny layer was suppressed by hydrocortisone (P0.05). Inflammation was also less pronounced following low dose hamamelis PC-cream and chamomile cream. Hamamelis PC-cream, however, appeared less potent than hydrocortisone. In general, visual scoring was more discriminatory than chromametry.The results have demonstrated an anti-inflammatory activity of hamamelis distillate in a PC-containing vehicle. A fourfold increase of drug concentration, however, did not produce an increase in activity.  相似文献   
78.
In this paper Reactive Dissociative Psychosis (RDP) is seen as a post-traumatic stress response and as a subcategory of Brief Reactive Psychosis (BRP). A review of the literature and the evolution of RDP from Hysteria and Hysterical Psychosis are given. Issue is taken with defining the duration of BRP as Brief. The authors argue that long-standing psychotic symptoms may be traumatically induced. The dissociative aspects of RDP as its key feature and the concomitant implications for accurate diagnosis are proposed. The usefulness of applying hypnosis in RDP treatment is summarized in a case study from Janet and detailed in a case from the authors' practice.This article was accepted for publication under the Editorship of Charles Charles R. Figley.  相似文献   
79.
Mohler J  Hart SC 《Air medical journal》1994,13(11-12):479-482
INTRODUCTION: Traditional methods of determining blood pressure may be unreliable (auscultation or palpation) or unavailable (direct arterial cannulation) in the air medical environment. The authors investigated the combination of a pulse oximeter with a standard sphygmomanometer (blood pressure) cuff as an alternative method. METHOD: The pulse oximeter is applied to a finger on the same upper extremity on which a standard blood pressure cuff had been applied. A baseline blood pressure was obtained by palpation or an automated blood pressure device. One minute later, the systolic blood pressure (SBP) was determined by inflating the blood pressure cuff until the pulsatile display on the pulse oximeter was obliterated. This was taken as the systolic blood pressure. RESULTS: Complete data were obtained on 116 patients, with 223 data pairs. The SBP as obtained by the baseline method was strongly correlated with the SBP obtained by the pulse oximeter display obliteration method (r = 0.90, p < 0.001). CONCLUSION: The obliteration of the wave form display on a pulse oximeter is an accurate, convenient, inexpensive and readily available alternative method of determining SBP.  相似文献   
80.
Information on academic and geographic career patterns was obtained through a survey of 93 urban and rural hospital administrators in the State of Washington in 1990 (90 percent response rate). A greater proportion of urban than rural administrators had advanced degrees (93 versus 74 percent). While the most common career pathways were "always urban" (39 percent) and "always rural" (20 percent), there was little support for the presumption that hospital administrators use rural positions as stepping stones into urban careers.  相似文献   
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