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61.
62.
The effect of high alveolar surface tension on alveolar epithelial permeability was studied in anesthetized closed-chest mongrel dogs. Alveolar surface tension was elevated by displacement of pulmonary surfactant from the alveolar hypophase by the aerosolized detergent dioctyl sodium sulfosuccinate (OT). After measurement of baseline hemodynamics, arterial blood gases, and airway pressure, the dogs were separated into groups: Group I inhaled a 1% solution of OT (15 mg/kg) in a vehicle of equal parts saline and ethanol; group II inhaled the same volume of vehicle without OT. The pulmonary clearance of technetium 99m diethylenetriamine-pentaacetic acid (99mTc-DTPA) (half-time in minutes) was studied immediately after aerosol (OT and vehicle) delivery and compared with that of historical control values. No change was seen in arterial blood gases and airway pressure after vehicle inhalation, whereas OT caused a marked fall in arterial oxygen tension and increase in airway pressure. Vehicle inhalation effected only a slight increase in DTPA clearance, whereas OT significantly reduced half-time over control and group II. These data suggest that high alveolar surface tension increases alveolar epithelial permeability.  相似文献   
63.
We studied the effects of calcium on transparency in homogenates of cortical and nuclear cells from calf lenses. Calcium was mixed into samples of homogenate to final concentrations between 0 and 50 mM and the transparency of the calcium-treated homogenates was measured using laser transmittance. In the presence of 10 mM calcium, the transmittance of cortical homogenate decreased 50% while the nuclear homogenate lost less than 4% transmittance after 24 h at 37 degrees C. To better understand the contribution of cytoplasm and membranes to opacity, the nuclear and cortical homogenates were centrifuged to separate membranes from the cytoplasm. When 10 mM calcium was added to cortical homogenate which was then centrifuged, the transmittance of the membrane fraction decreased nearly 60%, while the fraction without membrane decreased only 10%. The strong effect of calcium on the membrane fraction was accompanied by an increase in specific gravity of membranes from 1.23 to 1.32. Ten- and 20 mM calcium had no effect on transparency of membranes or cytoplasm separated from nuclear homogenate, and 50 mM calcium produced only a slight opacity. The results indicate that an effect on membrane-protein interactions may be important in the loss of transparency produced by calcium in cells of lens cortex.  相似文献   
64.
Summary Based upon the hypothesis that dipyridamole would potentiate the cytotoxicity of mitoxantrone and the combination of 5-fluorouracil (5-FU) and leukovorin, we performed a phase I/II trial of the combination of dipyridamole, 5-FU, leukovorin, and mitoxantrone in patients with metastatic breast cancer. The dose of dipyridamole was fixed at 175 mg/m2 by mouth every 6 h (700 mg/m2/day), based upon a previous phase I trial of oral dipyridamole with 5-FU and leukovorin. Dipyridamole therapy began 24 h prior to the first dose of chemotherapy and continued until 24 h after the last dose of chemotherapy for each course of treatment. At the initial dose level, leukovorin 200 mg/m2 was given intravenously immediately prior to 5-FU 375 mg/ m2 intravenously on days 1–5. Mitoxantrone 6 mg/m2 was given as a single dose on day 3. Unacceptable toxicity was observed at this dose level, leading to successive dose decrements rather than dose increments. The maximum tolerated dose was leukovorin 200 mg/m2 days 1–2, 5-FU 375 mg/m2 days 1–2, mitoxantrone 6 mg/m2 on day 2, and dipyridamole 175 mg/m2 every 6 h on days 0–3. Two responses were produced in 15 patients. This regimen is not recommended for further investigation in the treatment of breast cancer.  相似文献   
65.
Fibrin glue (FG) was used to achieve hemostasis of 16 splenic injuries in 14 patients. The etiologies of injury included five gunshot wounds, two stab wounds, four iatrogenic injuries, and five patients with blunt splenic trauma. The intraoperative blood loss averaged 1.8 +/- 2.4 (SD) liters and patients were transfused 3 +/- 2 units of blood perioperatively. The amount of FG required to achieve splenic hemostasis averaged 11 +/- 8 ml and varied directly with the grade of injury. One patient with a splenic hilar vascular injury (Grade V) underwent splenectomy following failure to achieve complete hemostasis despite the use of 25 ml of FG. All other splenic injuries were successfully managed using less than 25 ml of FG. Postoperative computerized tomographic (CT) scanning, performed in ten patients, was negative for rebleeding or abscess formation. The overall splenic salvage rate was 86%. FG was effective in achieving hemostasis of both superficial and deep splenic injuries. Its use as an adjunct in trauma surgery should result in increased splenic salvage rates compared with that obtained using conventional surgical techniques.  相似文献   
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67.
Background: Studies suggest that the period following completion of treatment can be distressing for cancer patients. One potentially important predictor of distress is physical symptoms/side effects during treatment.Purpose: A longitudinal, observational design was used to examine whether the number of physical symptoms/side effects experienced during treatment was a correlate of cancer-related distress and general distress 4 months after treatment completion, as measured by the Impact of Events Scale and the Mental Health subscale of the Short Form-36, respectively.Methods: Participants were 151 women who had completed chemotherapy and/or radiotherapy for ductal carcinoma in situ or stage 1 or 2 breast cancer. Hierarchical multiple regression was conducted with relevant sociodemographic, clinical, and psychiatric variables entered as controls.Results: Greater physical symptoms/side effects predicted greater total cancer-related distress, intrusive thoughts, and general distress. Physical symptoms/side effects did not significantly predict avoidance. Follow-up analyses indicated that the relationship between physical symptoms/side effects and general distress was mediated by both total cancer-related distress and intrusive thoughts.Conclusions: These results suggest that patients who experience greater physical symptoms/side effects during treatment are at greater risk for later cancer-related distress and, in turn, general distress. Future research should evaluate whether early intervention with these patients is effective in preventing or reducing distress in the posttreatment period. This work was supported by a grant from the National Cancer Institute (5R01 CA082822).  相似文献   
68.
Acrochordons (skin tags) are often considered clinically insignificant cutaneous redundancies that should be removed and destroyed with no histopathologic analysis performed. One rarely finds another neoplasm within an acrochordon. We describe a patient with an acrochordon that contained a squamous cell carcinoma that had features resembling a keratoacanthoma. This is the first time to our knowledge that an invasive squamous cell carcinoma has been described within an acrochordon.  相似文献   
69.
Clinical practice guidelines have emerged as a reality for medical practitioners over the past 20 years. Although virtually all groups interested in the development of practice guidelines hope for improvements in patient care, secondary expectations vary widely among those using them. Their use in daily practice by physicians has met with resistance from barriers including concerns of “cookbook” medicine, a loss of autonomy, and increased professional liability. The recent experience of the ACR in addressing these challenges illustrates that physicians are receptive to steps perceived to mitigate the risks accompanying the use of guidelines as well as to efforts to increase their understanding of implementing guidelines in clinical practice. The experiences of other medical societies and an inventory of future trends reveal additional challenges associated with the use of practice guidelines, as third parties look to guidelines as points of reference for gauging the performance of health care providers.  相似文献   
70.
Final year residents in training in Louisiana were surveyed regarding plans for medical practice and their perceptions of the importance of various factors in choosing practice locations. Most specialty groups selected smaller communities at similar rates. Growing up in small towns is associated with wanting to practice in small towns while concerns about opportunities for the family and income of the region are associated with wanting to practice in a larger city.This study was supported by the Louisiana Council for Statewide Planning for Physician Manpower through Contract No. 23058, Louisiana Department of Health and Human Resources.Ms. Samaha is a data analyst for the Louisiana Council for Statewide Planning for Physician Manpower; Robert R. Franklin, M.D. is Executive Secretary of the Council and Assistant Professor, Department of Biostatistics and Epidemiolgy, Tulane University School of Public Health and Tropical Medicine; Janet C. Rice is Assistant Pofessor, Department of Biostatistics and Epidemiology at the Tulane University School of Public Health and Tropical Medicine, New Orleans, Louisiana 70112.  相似文献   
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