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71.
Seventeen displaced intraarticular calcaneal fractures treated operatively were matched with 17 nonoperatively treated displaced intraarticular calcaneal fractures among Workers' Compensation Board patients. Matching criteria included type of fracture, age, year of injury, and occupation. After follow-up averaging 6.3 years and 5.4 years, respectively, no significant differences existed between the two groups in heel pain, subtalar motion, and return to work. However, in those fractures treated operatively, the overall clinical result was better when an anatomic reduction of the subtalar joint was achieved.  相似文献   
72.
AIMS: To study the pattern of expression and prognostic importance of c-erbB-2 protein in cervical carcinoma. METHODS: Sixty two cases of stage IB/IIA cervical carcinoma, representing the three main tumour types, were investigated immunohistochemically for the presence of c-erbB-2 protein expression, using a monoclonal antibody (CB11) to its internal domain. Follow up of at least five years' duration was available in all cases. RESULTS: Definite membrane staining was seen in 38.7% of cases. There was a strong correlation with poor survival (p less than 0.0001) particularly. For those with adenocarcinomas, this was the case when nodal metastases were present. In contrast, for squamous carcinomas and adenosquamous carcinomas, the association with a poor prognosis was most apparent in those patients without lymph node metastases. CONCLUSIONS: These findings raise the possibility that immunostaining for c-erbB-2 protein could be used as a prognostic marker and may help identify those patients for whom early adjuvant treatment might be beneficial.  相似文献   
73.
Morbidity and death during liver resection in children are due to hemorrhage and the consequences of massive transfusion. To overcome these problems, a new rapid method of blood transfusion was used in four children (8 to 35 months, 8.6 to 13 kg) undergoing extensive hepatic resection for tumor (tumor weight, 440 to 1625 gm). The rapid infusion device consisted of a roller pump and a bubble oxygenator-warmer circuit primed with washed packed red cells resuspended in fresh-frozen plasma and calcium-free balanced salt solution (Plasmalyte). The infusate was warmed, oxygenated, and buffered before it was administered. An average of 5130 ml per patient of this reconstituted blood was infused at an average rate of 122 +/- 45 ml/min, with peak infusion rates sometimes as great as 1 L/min. Cardiac output, pulmonary artery wedge pressure, body temperature, urine output, blood gases, blood chemistries, and coagulation factors remained unchanged during and after these massive transfusions. Blood transfusion at rapid rates required during pediatric liver resection can be accomplished safely if the storage lesion of the bank blood is previously corrected.  相似文献   
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This study describes ultrastructural changes in the pigmented hooded Lister rat retina, 3–12 months following X-irradiation with single doses of between 200 and 2000 cGy. The extreme radiosensitivity of the photoreceptor cells was underlined by the continued manifestation of fine structural changes and cell death up to 6 months post-radiation in animals receiving doses above 500 cGy. The retinal pigment epithelial (RPE) cells were more radioresistant than photoreceptors and RPE cell loss was only observed at doses of more than 1500 cGy. One year after irradiation with 1500 cGy the retinal vasculature showed capillary occlusion with some evidence of recanalisation. Telangiectasia was observed in the large retinal veins. Although the inner retinal neurones and glia1 cells showed no evidence of direct radiation damage, the nerve fibre layer adjacent to occluded retinal vessels demonstrated ultrastructural evidence of ischaemic neuropathy and retinal oedema. At doses above 1500 cGy the choriocapillaris showed platelet aggregation and capillary loss.  相似文献   
77.
We all work in a multigenerational workforce. With extremes in generations, skills are needed to foster understanding among staff. There are many myths and realities about the age-related generations. While there are challenges in working in a multigenerational workforce, the generational differences tend to be exaggerated while the similarities are overlooked. A better understanding of these generations allows us to prevent communication breakdown and to close the communication gaps where they exist, creating a unit of harmony rather that discontent.  相似文献   
78.
The effectiveness of prophylactic desmopressin acetate in reducing hemorrhage after cardiopulmonary bypass operations is controversial. We conducted a prospective, randomized, placebo-controlled, double-blind trial to determine its effectiveness and safety in such patients. Eighty-three evaluable patients undergoing valvular heart operations were randomized to receive desmopressin (0.3 microgram/kg) (41) or placebo (42) after cardiac bypass. Demographic characteristics were similar in both groups. There was no significant difference in total 24-hour blood loss between groups (desmopressin 1064.8 +/- 647.1 ml versus placebo 844.4 +/- 507.6 ml; p greater than 0.05), or in the requirement for red blood cell, platelet, or fresh frozen plasma transfusion, or for reexploration for control of hemorrhage. Neither was there a difference in the occurrence of thrombotic complications between groups. Analysis of factor VIII activity, von Willebrand factor, or von Willebrand factor multimers failed to show significant correlations with blood loss or differences between groups except for factor VIII activity, which was significantly higher in the desmopressin group 1 hour after operation than in the placebo group. A detailed comparative analysis of similar trials to determine the reasons for different outcomes suggests that desmopressin should not be used routinely as a prophylactic agent to reduce postsurgical hemorrhage, but that it may be beneficial when used in patients who already manifest excessive bleeding postoperatively.  相似文献   
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Background: Nitrous oxide is widely used in anesthesia, often administered at an inspired concentration around 70%. Although nitrous oxide interferes with vitamin B12, folate metabolism, and deoxyribonucleic acid synthesis and prevents the use of high inspired oxygen concentrations, the consequences of these effects are unclear.

Methods: Patients having major surgery expected to last at least 2 h were randomly assigned to nitrous oxide-free (80% oxygen, 20% nitrogen) or nitrous oxide-based (70% N2O, 30% oxygen) anesthesia. Patients and observers were blind to group identity. The primary endpoint was duration of hospital stay. Secondary endpoints included duration of intensive care stay and postoperative complications; the latter included severe nausea and vomiting, and the following major complications: pneumonia, pneumothorax, pulmonary embolism, wound infection, myocardial infarction, venous thromboembolism, stroke, awareness, and death within 30 days of surgery.

Results: Of 3,187 eligible patients, 2,050 consenting patients were recruited. Patients in the nitrous oxide-free group had significantly lower rates of major complications (odds ratio, 0.71; 95% confidence interval, 0.56-0.89; P = 0.003) and severe nausea and vomiting (odds ratio, 0.40; 95% confidence interval, 0.31-0.51; P < 0.001), but median duration of hospital stay did not differ substantially between groups (7.0 vs. 7.1 days; P = 0.06). Among patients admitted to the intensive care unit postoperatively, those in the nitrous oxide-free group were more likely to be discharged from the unit on any given day than those in the nitrous oxide group (hazard ratio, 1.35; 95% confidence interval, 1.05-1.73; P = 0.02).  相似文献   

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