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91.
92.
Benson HR 《Radiology management》1996,18(1):40-46
After the benchmarking team has accumulated data for the development of comparisons, it must be validated for completeness and consistency. Various factors can skew the analysis and should be watched: Subjective interpretations of survey questions. Lack of common definitions. Composition of input data. External factors and extraordinary events. After verifying consistency of data gathered from benchmarking partners, calculate appropriate statistics for the performance metric. Typical data tabulations are: mean, median, ratio, minimum and maximum value, normal operating range, standard deviation and correlation coefficient. Statistics derived from the data produce the benchmark against which you will measure your institution's performance. Gap analysis establishes the difference between your internal operation's performance and that of the benchmark. Information developed from properly collected data will help you determine reasons for the gap between your performance and the benchmark and project future trends. The next step is to develop an action plan based on what has been learned from benchmarking and targeted to improving performance in areas that further the strategic goals of the institution. In addition to determining performance goals, you must analyze the decision-making process involved in making changes that will move you toward those goals. Since the goal of benchmarking is to improve the organization, the team must present its analysis to those members of management who can approve an action plan. Changes resulting from benchmarking can range from incremental improvement of existing practices all the way to reenginering. Action plans are designed to effect change at levels that will vary according to the goals that have been set. The more incremental the change, the easier the implementation. The more radical the change, the greater the reward. 相似文献
93.
Purpose
Several different methods to construct a bladder substitute after cystectomy have been described. We evaluated our experience with the Studer ileal ureter neobladder during the last 5 years.Materials and Methods
We reviewed retrospectively the results in 32 patients who underwent construction of a slightly modified ileal neobladder from that originally described. Mean followup was 25 months (range 6 to 68).Results
Patients experienced few complications and only 1 required reoperation. Daytime and nighttime continence rates were 94 and 74 percent, respectively. One patient sustained a ureteral stricture resulting in hydronephrosis (1 of 64 renal units).Conclusions
The results reveal the ileal neobladder to be an easily constructed pouch with a low complication rate, and a high success rate in regard to continence and the establishment of adequate capacity at low pressure. Within the study period upper tract preservation was excellent. However, a 10 to 15-year followup is indicated to confirm our initial results. 相似文献94.
Luck JV Logan LR Benson DR Glasser DB 《The Journal of the American Academy of Orthopaedic Surgeons》1996,4(6):297-304
Orthopaedic surgeons practicing in areas with a high prevalence of human immunodeficiency virus (HIV) infection may expect that up to 7% of their patients who undergo emergent procedures and 1% to 3% of those who undergo elective surgery will be HIV-positive. Although basic science studies have demonstrated impairment of defenses to routine orthopaedic pathogens as well as to opportunistic organisms, clinical studies have shown that this impairment has not resulted in an increased incidence of postoperative infections or failure of wound healing in the asymptomatic HIV-positive patient. Even for the symptomatic patient, current medical management appears adequate to reduce the risk of early postoperative infection. The HIV-positive patient with a pros-thetic implant may be at increased risk for late hematogenous implant infection as host defenses diminish. Regular medical attention, prophylactic antibiotic therapy before dental work and invasive procedures, and early evaluation and treatment of possible infections are especially important in this setting. Decisions regarding elective surgery should be made on a risk-benefit basis. Because the risk of surgical complications increases with progression of the dis-ease, guidelines for elective surgery should include an assessment of the HIV-positive patient's immune status, including the CD4 lymphocyte count, history of opportunistic infection, serum albumin level, the presence of skin anergy, and the state of nutrition and general health. 相似文献
95.
Calculating the appropriate dosage of a drug and the right equipment size during an emergency situation can be a time-consuming, frustrating, and error-prone process, considering the shortage of time during a resuscitation. A microcomputer program was developed to aid in the care of pediatric patients in emergency or 'code' situations. This is accomplished by use of a printout of a patient-specific chart for most needed critical care drugs and equipment used during an emergency. This program is written in "C" language and is menu-driven. 相似文献
96.
The physiological responses to four levels of radiant heat (R) in combination with two work loads and three ambient humidity levels were studied on seven clothed young men. The globe temperature (tg) ranged from 40 to 74°C; metabolic work load (M) was either 20 or 50% of maximal aerobic capacity (V?02 max); ambient vapor pressure was either 13 or 23 mm Hg; and dry-bulb temperature (tdb) was 38 or 49°C. The criteria for heat strain were the changes in rectal temperature (Tre), mean skin temperature (Tsk), heart rate (HR), and sweating (Sw). Stress was defined by the calculated heat load requiring dissipation (M + R + C = Ereq), the ambient evaporative capacity (Emax), and the skin wettedness (w), defined as the ratio of Ereq/Emax. The progressive increase in R resulted in a concomitant rise of Tre and HR reflecting the physiological strain. Similarly the increase in either M or in the humidity resulted in higher Tre and HR. The changes in R or Emax were best defined by the w, thus w and the physiological responses were highly correlated. For practical application a multiple regression of the increments of HR(ΔHR) on tdb above neutral (25°C) and on tg above tdb was derived as follows: It was concluded that the calculated skin wettedness is most suitable in the evaluation of heat stress. 相似文献
97.
98.
Joe Gabica W. W. Benson Michael Watson 《Bulletin of environmental contamination and toxicology》1976,15(2):155-161
Squaxon (1,1'methylenedi-2 napthol; bis (2 hydroxy-1-napthyl) methane) was discovered by MacPhee and Ruelle (1968, 1969) to exhibit piscicidal properties that are highly species specific. The chemical is lethal to the Northern (Ptychocheilus oregonensis) and the Umpqua (P. umpquae) squawfish, freshwater cyprinids common to the Pacific Northwest, at water treatment concentrations of less than 100 parts per billion (ppb). Other species of fish, including the more desirable salmonids with which the squawfish competes ecologically, are unaffected until this dosage has been increased severalfold. Because squawfish are widely regarded as undesirable for food or sporting purposes, and because competition from squawfish has severly depleted salmonid populations in some areas (Thompson, 1959; Jeppson and Platts, 1959) the potential use of squaxon for fisheries improvement is quite obvious. Squaxon is currently being tested for this purpose on an experimental basis in selected areas in Idaho, Oregon and Washington, pending federal clearance for more widespread application.Commercially formulated squaxon currently being field tested is dispersed as an ethanolic solution of the monosodium salt. The treatment solution consists of 39.5 per cent (by weight) 1,1 methylene-di-2 napthol dissolved in 60 per cent denatured ethyl alcohol. Traces of sodium hydroxide are also present in the commercial solution (Keating, 1972). We report here an analytical method by which petroleum ether-extracted, brominated squaxon can be quickly and easily detected in water and fish tissue by electron capture gas chromatography.This research was supported under Contract No. 68-02-0552 by the Pesticide Community Studies Division, Pesticides Office Environmental Protection Agency, through the Idaho Department of Health and Welfare. 相似文献
99.
Xanthoma disseminatum (XD) is a rare mucocutaneous xanthomatosis classified as a benign form of non-Langerhans' cell histiocytosis. The case history is presented of a 61 year old woman with XD who developed dyspnoea and spirometric features of airflow obstruction. Bronchoscopy and computed tomography confirmed involvement of the large and medium sized bronchi and she subsequently died from acute respiratory failure. The post-mortem findings and the importance of respiratory tract disease in this unusual condition are discussed. 相似文献
100.
Expression of senescence-associated beta-galactosidase in enlarged prostates from men with benign prostatic hyperplasia 总被引:8,自引:0,他引:8
Choi J Shendrik I Peacocke M Peehl D Buttyan R Ikeguchi EF Katz AE Benson MC 《Urology》2000,56(1):160-166
OBJECTIVES: Cellular senescence is a unique cellular response pathway thought to be closely associated with the aging process. The senescent phenotype is characterized by the loss of a cell's ability to respond to proliferative and apoptotic stimuli even while normal metabolic activity and vitality is maintained. Recently, a novel biomarker, senescent-associated beta-galactosidase (SA-beta-gal), was found to identify cells with the senescent phenotype. In the present study, we examined whether human prostatic epithelial cells adopt a senescence-associated phenotype after prolonged culture and analyzed a series of human benign prostatic hyperplasia (BPH) specimens to determine whether the cellular senescence process might be a factor in the development of BPH. METHODS: A primary culture of epithelial cells was established from the normal tissue of the peripheral zone of a radical prostatectomy specimen and was serially passaged until senescence. Forty-three human prostate specimens were obtained subsequent to radical prostatectomy or transrectal ultrasound-guided biopsy. The cultured cells and tissue specimens were histochemically stained to reveal the expression of SA-beta-gal, the cellular senescence biomarker. RESULTS: As has been reported for other types of cultured cells, human prostatic epithelial cells demonstrated widespread expression of the cellular senescence marker, SA-beta-gal, on prolonged culture. In our survey of hypertrophied human prostate tissues, 17 specimens (40%) of the 43 analyzed demonstrated positive staining for SA-beta-gal. In these tissues, SA-beta-gal expression was noted only in the epithelial cells. No statistical correlation (P = 0.42) between the chronologic age of the patient donor and SA-beta-gal expression was found. However, a high prostate weight (greater than 55 g) was found to correlate strongly with the expression of the SA-beta-gal biomarker (P = 0. 0001). CONCLUSIONS: Cultured prostatic epithelial cells expressed SA-beta-gal on reaching replicative senescence in vitro. The survey of human BPH specimens for the senescent marker showed that prostatic epithelial cells in patients with BPH with more advanced enlargement of the prostate (greater than 55 g prostate weight) expressed SA-beta-gal, and the prostates from patients with BPH that weighed less than 55 g tended to lack senescent epithelial cells. On the basis of these results, we propose that the accumulation of senescent epithelial cells may play a role in the development of the prostatic enlargement associated with BPH. 相似文献