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Serum prostate specific antigen, prostate specific antigen density and free:total prostate specific antigen are known to be useful for determining the risk of prostate cancer in patients undergoing prostate cancer screening. The patient with a positive biopsy presents no future prostate specific antigen dilemma. Those with negative biopsies often go on to numerous repeat biopsies. Our goal was to establish criteria that could be used to identify patients who will require repeat prostate biopsies (possibly false negative initial biopsy), while not exposing the low risk population (probable true negative initial biopsy) to additional invasive procedures. Between March 1991 and March 1998, 148 patients who had a biopsy for an elevated prostate specific antigen value (4.1-10.0) or an altered digital rectal examination, had no cancer found in the specimen. From these, 51 (34.4%) had repeated biopsies, while the others persisted on close follow-up. We examined their serum prostate specific antigen, prostate specific antigen density and free:total prostate specific antigen value, as well as their age and histology results of the initial and repeat biopsy, to determine if any predictor of the need for a repeat biopsy could be identified. Eight (15.7%) from 51 men who had repeat biopsy had prostate cancer detected. Forty three (84.3%) patients persisted with a negative biopsy, despite filling the criteria for re-biopsy. Multivariate analysis failed to identify any significant predictors of prostate cancer in the repeat biopsy group. Despite initial success, the prostate specific antigen derivatives and free:total prostate specific antigen have not safely limited the number of biopsies performed for an abnormal prostate specific antigen (4.1-10.0). Neither prostate specific antigen density nor free:total prostate specific antigen predicted the need for repeat biopsy in this specific group. The results of this ongoing study demonstrate that to date, prostate specific antigen and prostate specific antigen derivatives can not be utilized to determine which patients will be at high risk for requiring repeat prostate biopsy. All patients must be closely monitored for evidence of a change in status from benign to malignant disease, and new markers for this purpose are urgently needed.  相似文献   
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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   
76.
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   
77.
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   
78.
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:
△HRbpm = 0.96(tdb ? 25°C) + 0.81(tg ? tdb) ? 1
It was concluded that the calculated skin wettedness is most suitable in the evaluation of heat stress.  相似文献   
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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   
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