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991.
Study objective: The alteration of a knee immobilizer into a sharp weapon by a prisoner prompted us to survey neighboring penal institutions to determine the frequency of such events. Design: We mailed a nine-item survey to all detention facilities in Tennessee, Arkansas, and Mississippi. A second survey was sent to nonresponding institutions 6 weeks after the initial mailing. Setting: The Regional Medical Center at Memphis, the designated facility for evaluation and treatment of prisoners from the county jail and state penitentiary. Participants: Survey respondents included 25 state penitentiaries, 31 county jails, 1 state minimum-security facility, 1 state maximum-security facility, 1 work-release center, 1 county detention center for drunken-driving offenders, and 1 federal penitentiary. Results: Of the 81 institutions surveyed, 77% responded to one of the two mailings. Forty percent responded in the affirmative when asked whether stolen or unauthorized medical equipment from outside their institutions had been discovered among inmates. When respondents were questioned as to whether medical equipment, prescribed or not, had been used or altered in a criminal manner, 34% responded "yes." Medications and medical appliances were listed in the responses. Conclusion: A survey of 81 local and neighboring penal institutions in a three-state area revealed that the illicit use of medicine and medical devices by prisoners is a legitimate safety concern of prison personnel and health care workers when medical care for inmates must be sought outside the security of their institutions. The modification of medical equipment into weapons by incarcerated patients, although clearly recognized as a security and safety problem by police authorities, appears to be unappreciated by health care workers providing episodic care to inmates. [Hayden JW, Laney C, Kellermann AL: Medical devices made into weapons by prisoners: An unrecognized risk. Ann Emerg Med December 1995;26:739-742.]  相似文献   
992.
Objective: Our purpose was to determine whether primary and preventive care is practiced by a university obstetrician-gynecologist group practice.Study design: A retrospective chart review spanning 2 years of four academic physicians' private practices was performed. A total of 335 patients were reviewed with 739 patient encounters and 1032 patient problems identified. The definition of a primary care physician according to The American College of Obstetricians and Gynecologists was used to standardize data collection and evaluation.Results: Obstetric complaints accounted for 27.7% of all visits, whereas 65.4% were for gynecologic problems. Almost 7% of all complaints were neither obstetric nor gynecologic, and of those 74.6% were primary care problems completely managed by the obstetrician-gynecologist. Only 19.7% of these were referred for management. More than 89% of all encounters () involved some element of primary care.Conclusion: This study provides evidence that the majority of health care provided by the obstetrician-gynecologists is primary care.  相似文献   
993.
Automated anesthesia recordkeepers have been used to monitor patients during surgery in up to 90% of cases at The Ohio State University. The record-keeping devices are complex and can be difficult to troubleshoot. The 1st-CLASS Fusion Program, an expert system shell-program, has been programmed to allow the resident or nurse anesthetist to solve the two most common types of problems associated with the recordkeeper: printer problems and patient monitor problems. Use of this program allows the resident or nurse anesthetist to troubleshoot the recordkeeper quickly and accurately and promotes in the user a sense of competence and control over the technology.  相似文献   
994.
Objective. The objective of our study was to determine if clinical observation of pressure-flow relationships (PFR) can differentiate between partial external obstruction (obstruction) and infiltration as a cause of poor performance of gravity-fed infusions.Methods. A total of 24 patients with functional intravenous cannulae in situ had obstruction simulated by the application of a tourniquet proximal to the cannula. The change in flow (F) for a discrete change in pressure (P) was determined in each case by counting drop rates at two different elevations of the fluid reservoir level, 10 cm apart. The same process was repeated in 15 patients in whom the cannula was in an extra vascular location (infiltration). Three sizes of cannula—16-gauge, 18-gauge, and 20-gauge—were examined, with equal distribution of sizes in each group. The effect on flow rates of inflating a blood pressure (BP) cuff proximally on the cannulated limb was assessed. The ratio P/F is the total resistance of the infusion system, and by subtracting known values for resistance of infusion tubing and cannula, the venous or tissue resistance was calculated.Results. There was a statistically significant difference between the change in flow for obstructed compared with infiltrated cannulae for the same change in pressure for each cannula size. The mean venous resistance was 23 mm Hg/L/hr, while that of tissue was 280 mm Hg/L/hr, with no overlap between groups. There was no effect on flow rate with blood pressure cuff inflation in the infiltrated group whereas flow progressively fell in the obstructed group.Conclusions. Clinical observation of PFRs in poorly functioning gravity-fed IV infusions can assist in detecting infiltration as a cause. Inflation of a blood pressure cuff will further impair flow where the cannula is intravascular, but will have no effect in an extravascular location.  相似文献   
995.
Although the traditional therapy for blunt traumatic rupture of the thoracic aorta (TRA) is immediate operative repair, there may be a selective role for delayed repair, particularly in patients with head trauma, respiratory failure, or cardiac dysfunction. The present study examines the hypothesis that TRA can be managed by selective delayed operative repair. Clinical data were collected from 59 consecutive patients with TRA at a regional trauma unit. All TRAs were at the aortic isthmus. Patients were retrospectively classified into three groups: group I (n=12) included patients who either arrived in extremis or rapidly became unstable during triage; group II (n=3) included patients who had no contraindications to early repair and underwent repair at the time of diagnosis; and group III (n=44) consisted of patients who because of concomitant injuries or sepsis required initial admission and management in the intensive care unit until their clinical status had improved sufficiently to allow for deliberate delayed operative repair of the TRA. The delay ranged from 1 day to 7 months. Eight patients have yet to undergo repair and remain well at follow-up from 1 to 4 years. Overall survival rates in groups I, II, and III were 17%, 100%, and 82%, respectively. The surgery-related mortality rate in group III was 10% (three patients). Only two (4.5%) patients in group III died as a result of a ruptured aorta within 72 hours of admission. In conclusion, contrary to surgical doctrine, TRA may not require immediate operative repair in all cases, but may instead be managed selectively depending on the patient's clinical status.  相似文献   
996.
Background: Hybrid, combined or mixed bariatric surgery is the combination of a degree of ‘malabsorption’ (as achieved by the intestinal bypass) with a ‘rrestriction’ (as achieved by gastric bypass or gastroplasty), thereby simultaneously reducing the absorption of fats in the small bowel and decreasing the intake of food. Methods: A modification of the bilio-pancreatic diversion (BPD) with a duodenal switch procedure, vertical lineal gastrectomy and preservation of the pylorus, has been used in 23 patients. The antropyloric pump and 4 cm of the duodenum are left intact to preserve physiologic gastric emptying and to prevent anastomotic ulcer. The use of staplers and continuous running sutures reduces surgical risks and operative time. Results: One patient, converted from a vertical gastroplasty, had an intrathoracic esophageal perforation and died of multisystemic organ failure, a mortality rate of 4.5%. One patient had a partial dehiscence of the laparotomy wound. Three patients developed subcutaneous seromas. Mean weight losses during the first 4 months were 13, 11, 6 and 5 kg, with a loss of 70% of excess weight in patients approaching 1 year. No patient needs treatment for diarrhea. No serious secondary side-effects have been detected. Conclusion: This operation appears to result in very satisfactory weight loss, improved quality of life, and a low incidence of complications.  相似文献   
997.
998.
Background: this study was designed to characterize some of the biochemical and molecular genetic changes during reversion of human fat cells. Methods: mature adipocytes were isolated from greater omental fat tissue of eight lean and 14 massively obese persons by established methodology. Results: at day 7 of adherence to Leighton tubes, there was appreciable depletion of triacylglycerol, as well as assumption of an elongated contour. Relatedly, there was an increase in the expression of β-actin mRNA and a significant decrease in the specific activity of cytosolic glycerophosphate dehydrogenase. The decrement in the specific activity of glycerophosphate dehydrogenase, after 7 days in culture, was significant at p < 0.001. Basic fibroblast growth factor at 10 ngml-1 accelerated significantly (p < 0.03) the decrease in the specific activity of glycerophosphate dehydrogenase in adipose cells from lean subjects. In contrast, basic fibroblast growth factor had no significant influence on cells from massively obese persons. Conclusion: such resistance may contribute to the intractability of massive obesity.  相似文献   
999.
Our current understanding of the complex processes involved in wound healing is based mainly on studies of animal models. Although this information has been useful, it may not totally reflect the response found in human beings. For example, human beings have a tendency to either "overheal," as seen in keloids and hypertrophic scar formation, or have deficient healing, as seen in chronic ulcer formation. No animal models are available to analyze these human clinical pathologic conditions. Therefore the objective of this study was to analyze the wound healing response in a large population (n = 40) of normal healthy human beings as a first step to begin studies of abnormal human wound healing. Simultaneously, a comparison was made between the polyvinyl alcohol implant and the expanded polytetrafluoroethylene implant model. Under sterile conditions with the use of local anesthesia, two preweighed polyvinyl alcohol implants and two standard 6 cm expanded polytetrafluoroethylene implants were placed subcutaneously in the upper arm of each subject. High-performance liquid chromatography was used to quantitate isoleucine and hydroxy-l-proline in acid hydrolysates of each implant. Isoleucine was used as an indicator of protein content in the tissue sample, whereas hydroxyproline reflected collagen content. No infectious or hemorrhagic complications were found in the 40 volunteers included in the study. No significant difference was found in isoleucine or hydroxy-l-proline content between postoperative day 7 polyvinyl alcohol implants and day 14 polyvinyl alcohol implants. In contrast, both isoleucine and hydroxy-l-proline content were significantly increased in day 14 expanded polytetrafluoroethylene implants compared with day 7 implants (p < 0.005 and p < 0.001, respectively). In addition, the ratio of hydroxy-l-proline to isoleucine was significantly increased in day 14 expanded polytetrafluoroethylene implants compared with day 7 expanded polytetrafluoroethylene and both day 7 and day 14 polyvinyl alcohol implants (p < 0.001). This observation suggests that by 14 days implantation of expanded polytetrafluoroethylene stimulated an increased deposition of collagen. No significant differences were found in the hydroxy-l-proline to isoleucine ratios among day 7 expanded polytetrafluoroethylene, day 7 polyvinyl alcohol, and day 14 polyvinyl alcohol implants. Histologic analyses correlated with the biochemical findings. These results suggest that expanded polytetrafluoroethylene may be the preferred implant for studies designed to examine pathologic processes associated with retarded wound healing. In contrast, the polyvinyl alcohol implant may be better suited for studies where a low background response is required. Moreover, the extreme variability in normal healthy volunteers seen in this study correlates clinically with the finding that, among the normal adult human population, there is a heterogeneous wound healing response.  相似文献   
1000.
Improved survival in young women with breast cancer   总被引:3,自引:0,他引:3  
Background: Young age has been hypothesized to be an adverse prognostic factor for women with breast cancer. This association, based on historical data, may not reflect recent advances in breast cancer management. Methods: A retrospective study was conducted of all women age 30 or younger who underwent definitive operation at our institution for primary operable breast carcinoma during one of two consecutive 20-year periods (1950–1969 or 1970–1989). All cancers were restaged according to current staging criteria. Actuarial survival and recurrence-free survival rates from the two patient eras were compared with each other and with published statistics for older breast cancer patients. Results: Eligibility criteria were met by 81 women from the 1950–1969 era and 146 women from the 1970–1989 era. Histologic diagnoses, tumor sizes, incidence of axillary nodal metastases, number of positive nodes, and American Joint Committee on Cancer stage at presentation were similarly distributed in the two eras. Despite these similarities, improved survival (p=0.009) was observed in the later era. Local recurrences were also more common (p<0.05) in the later era in association with less extensive resections. These local recurrences had an adverse impact on recurrence-free survival in the later era, but no concomitant decrease in overall survival was observed. Node-positive patients who received chemotherapy demonstrated a trend toward improved survival (p=0.06) compared with node-positive patients who did not. Survival for patients in the later era was similar to that for older women as reported in other published series. Conclusions: The stage of presentation of breast cancer in women 30 years or younger appears unchanged from prior decades, but survival has improved in association with the use of less extensive surgical resections and the introduction of cytotoxic chemotherapy. With current treatment, primary operable breast cancer in young women appears to have a similar prognosis to breast cancer in older women.Results of this study were presented at the 47th Annual Cancer Symposium of The Society of Surgical Oncology, Houston, Texas, March 17–20, 1994, and was judged Best Clinical Paper in the Resident/Fellow Essay Contest.  相似文献   
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