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81.
The purpose of this study was to compare neutrophil cidal activity during general or spinal anaesthesia. Assays were performed on neutrophils extracted from the blood of patients after surgery had been under way for one hour. First, the ability of the neutrophils to kill a standard laboratory strain of S. aureus was examined. Neutrophils extracted from the blood during surgery in the spinal anaesthetic group and incubated with the staphylococci for one hour killed twice as many bacteria than those from two groups of patients that received halothane or isoflurane general anaesthesia (P < 0.05). This effect persisted, to a lesser extent, in the spinal group neutrophils after two hours of incubation with the bacteria. Second, neutrophils from patients under the same conditions of surgery and anaesthesia were tested to examine the effect of the different anaesthetic techniques on neutrophil biocidal mechanisms. Neutrophils extracted during surgery in the spinal group released more superoxide in response to phorbol-12-myristate-13-acetate (PMA) than those from both groups of patients that received general anaesthesia (P < 0.05). It is concluded that there is an increased state of reactivity of the neutrophil cell membrane NADPH oxidase system in patients receiving spinal anaesthesia than in patients receiving general anaesthesia.  相似文献   
82.
Objective. To evaluate the utility of the iSTAT blood analyzer, a bedside device for hematocrit, sodium, potassium, and glucose measurement during cardiopulmonary bypass (CPB).Methods. Forty patients scheduled for elective CPB were evaluated prospectively. In addition to using the iSTAT analyzer, blood samples were analyzed at four time points: following induction of anesthetic, 10 min. after initiation of CPB, 60 min. after initiation of CPB, and following heparin neutralization by protamine. Blood glucose concentration was measured by the hospital laboratory using a Kodak Analyzer and by a glucose meter, electrolytes were evaluated by the Kodak Analyzer and BGE (a device which is commonly used for satellite laboratory determinations of electrolyte and blood gas results), and hematocrit samples were measured by the hospital laboratory using an NE 8,000 and a centrifuge. The means and standard deviations of the differences between the methods were calculated.Results. The hematocrit values determined by the iSTAT machine, when adjusted for the level of total protein (according to manufacturer's directions), differed from the laboratory values by 0.53 = 1.46 percentage points. An alternative to measuring total protein and making the adjustment is simply adding 1 % to the hematocrit in the pre-CPB period and 3% on-CPB or post-CPB, which we found to yield values that differed from the laboratory by 0.52 ± 1.42 percentage points. For all four tests (hematocrit, sodium, potassium, and glucose) the iSTAT had a similar relationship to the laboratory values as did the other commonly used means (centrifuge, BGE, and glucose meter) of clinical evaluation.Conclusion. In summary, we found that in patients undergoing CPB, the iSTAT values agreed sufficiently well with standard laboratory values and that the iSTAT instrument can be relied upon for bedside measurements.Presented in part at the Annual Meeting of the Society of Cardiovascular Anesthesiologists, Philadelphia, PA, May 1995, and at the 70th meeting of the IARS, Washington DC, March 1996. Supported in part by a grant by iSTAT Corporation.  相似文献   
83.
Summary The lead content of whole blood of 62 sheep grazed continuously for 6 months near a major highway was compared with 38 sheep from a nearby uncontaminated area. Mean values of 0.90 and 0.20 g/ml were obtained. Four sheep from the contaminated area were placed in an uncontaminated paddock and the lead content of the blood decreased rapidly during the first 10 days and thereafter more slowly. After 185 days, blood lead levels had still not quite reached normal levels.Animals from an uncontaminated area showed an immediate rise in the blood lead levels when placed near a major highway. Sheep placed in a concrete pen away from motor vehicle exhaust emissions showed a rise in lead levels when fed with, forage cut from the verges of a busy highway. Sheep placed near a highway and fed with forage from an uncontaminated area showed an increase of lead levels in the blood, comparable to that of the previous experiment. It was concluded that lead uptake by ingestion of polluted forage and by inhalation of airborne particulates are both mechanisms responsible for enhanced lead levels in ovine blood.  相似文献   
84.
OBJECTIVES: Two pilot studies were conducted to produce efficacy data on an observational tool designed to assess the use of Universal Precautions (UP) in patient care settings. The instrument addresses barrier precautions, hand-washing, handling of sharps, and avoidance of unprotected mouth to mouth resuscitation. DESIGN: The Universal Precautions Assessment Tool was submitted to a panel of 3 experts to establish consensual validity. It was pilot tested by 2 simultaneous observers to establish interrater reliability. SETTING: Pilot Study I was conducted in 3 different units within a 100-bed U.S. Army hospital. Pilot Study II was conducted in the emergency department of a large university-based hospital. PARTICIPANTS: Subjects observed were registered nurses providing acute patient care. RESULTS: Two simultaneous raters calculated UP compliance rates of 76.4% and 78.6%, respectively, for 9 nurses in Pilot Study I, and 62% and 65%, respectively, for 5 nurses in Pilot Study II. The intraclass correlation coefficient for the raters' scores in Pilot Study I was 0.992 with a 95% confidence interval (0.979, 0.997). Consensual validity was established. CONCLUSIONS: The instrument has acceptable interrater reliability under the conditions used. Limitations to use include the possibility of a Hawthorne effect and the fact that assessing proper implementation of UP occasionally relies on a "judgment call" by the observer. With test conditions adjusted to minimize these limitations and with proper consideration of sample size, the tool can be used by researchers and by monitors of hospital quality control to measure UP compliance of caregivers individually or collectively.  相似文献   
85.
Attitudes to autologous blood donation have been surveyed in a group of 38 postoperative bariatric patients. Only two patients (5%) declined to participate. Twenty-eight of 38 (70%) successfully predeposited autologous blood. Twenty-five of 28 donors (90%) had done so at the suggestion of their surgeon. Concern about contracting AIDS was the motivating factor in the majority of patients (21 patients, = 55%). Lack of infectious complications in general was cited by an additional four (11%). All respondents would donate autologous blood in the future, and would recommend the procedure to others who were about to undergo elective surgery. There was an increase from 29% to 50% who stated that, following their autologous donation experience, they would consider being homologous volunteer blood donors in the future.  相似文献   
86.
Summary The disposition of cisplatin was evaluated in 28 children and adolescents with cancer, as part of a phase II clinical trial. Patients received either 30 mg/m2 (11) or 90 mg/m2 (17) of cisplatin as a 6-h IV infusion. Serum samples and divided urine collections were obtained over 48 h following completion of the cisplatin infusion, and were assayed in duplicate for total platinum by atomic absorption spectrophotometry. Serum samples obtained up to 4 h after three cisplatin infusions were assayed for parent (free) cisplatin following ultrafiltration. The mean (±SE) elimination half-life of free cisplatin in serum was 1.3 (±0.4) h. Serial serum concentrations of total platinum following 90 mg/m2 dosages were adequately described by a biexponential equation. The mean (±SE) serum T1/2 of total platinum was 0.42 (±0.10) h and the mean (±SE) T1/2 was 44.43 (±8.24) h. The intercompartment distribution rate constants of a two-compartment kinetic model indicate extensive tissue accumulation of total platinum, with a rate of transport into tissue compartments (K12) that is about six times the rate of transport out of tissues (K21). The mean (±SE) renal clearance of total platinum from 0–3 h was 37.36 (±11.96) ml/min/m2 and 35.8 (±13.6) ml/min/m2 for the 30 mg/m2 and 90 mg/m2 groups, respectively. This value decreased to 3.25 (±0.94) and 2.16 (±0.4) ml/min/m2 for the two groups by the 6–12 h interval, and remained between 1 and 3 ml/min/m2 for the duration of the observation period. The ratio of total plantinum clearance to creatinine clearance decreased significantly(P<0.05) beginning 3 h post-infusion. The change in renal clearance of total platinum is apparently a function of two independent first-order processes for renal clearance of parent drug and cisplatin metabolites.  相似文献   
87.
Summary Levels of lead were determined in primary feathers of 1008 woodcocks (Philohela minor) shot by hunters in 32 states of the species' United States range. Lead levels did not vary by sex or age but varied significantly (P<0.05) by state. Generally, levels were found to be low (<30 g/g d.w.) in the birds examined. No significant correlations were found between mean lead levels and 10 human population, highway and highway traffic parameters examined.  相似文献   
88.
Three subjects were tested on an information processing task on a daily basis for a period of 70 d. Performance measurement included reaction time, movement time, and information processing rate. The data set obtained was subjected to Fast Fourier Transforms (FFT) in an attempt to identify periodicities in performance. Twelve significant harmonics were identified and nine were found to be within 1 d of at least one of the cycles hypothesized by the theory of "biorhythms." The probability of this occurring by chance is remote (p less than 0.05), assuming a uniform distribution of significant amplitude. The results were interpreted as suggesting the possibility of a biorhythmic influence in the performance of the task.  相似文献   
89.
PURPOSE: To assess oregovomab as consolidation treatment of advanced ovarian cancer and refine the immunotherapeutic strategy for subsequent study. PATIENTS AND METHODS: Patients with stage III/IV ovarian cancer who had a complete clinical response to primary treatment were randomly assigned to oregovomab or placebo administered at weeks 0, 4, and 8, and every 12 weeks up to 2 years or until recurrence. The primary end-point was time to relapse (TTR). RESULTS: One hundred forty-five patients were treated with oregovomab (n = 73) or placebo (n = 72). For the population overall, median TTR was not different between treatments at 13.3 months for oregovomab and 10.3 months for placebo (P =.71). Immune responses were induced in most actively treated patients. This was associated with prolonged TTR. Quality of life was not adversely impacted by treatment. Adverse events were reported with similar frequency in oregovomab and placebo groups, indicating a benign safety profile. A long-term survival follow-up is ongoing. Cox analysis of relapse data identified significant factors: performance status, CA-125 before third cycle, and baseline CA-125. Further evaluation identified a subpopulation with favorable prognostic indicators designated as the successful front-line therapy (SFLT) population. For the SFLT population, TTR was 24.0 months in the oregovomab group compared with 10.8 months for placebo (unadjusted hazard ratio of 0.543 [95% CI, 0.287 to 1.025]), a hypothesis-generating observation. CONCLUSION: Consolidation therapy with oregovomab did not significantly improve TTR overall. A set of confirmatory phase III studies has been initiated to determine whether the SFLT population derives benefit from oregovomab treatment.  相似文献   
90.
PURPOSE: Preclinical and clinical studies have demonstrated that inhibition of prenylation can radiosensitize cell lines with activation of Ras and produce clinical response in patients with cancer. The aim of this study was to determine the maximally tolerated dose of the dual farnesyltransferase and geranylgeranyltransferase I inhibitor L-778,123 in combination with radiotherapy for patients with locally advanced pancreatic cancer. EXPERIMENTAL DESIGN: L-778,123 was given by continuous intravenous infusion with concomitant radiotherapy to 59.4 Gy in standard fractions. Two L-778,123 dose levels were tested: 280 mg/m2/day over weeks 1, 2, 4, and 5 for dose level 1; and 560 mg/m2/day over weeks 1, 2, 4, 5, and 7 for dose level 2. RESULTS: There were no dose-limiting toxicities observed in the eight patients treated on dose level 1. Two of the four patients on dose level 2 experienced dose-limiting toxicities consisting of grade 3 diarrhea in one case and grade 3 gastrointestinal hemorrhage associated with grade 3 thrombocytopenia and neutropenia in the other case. Other common toxicities were mild neutropenia, dehydration, hyperglycemia, and nausea/vomiting. One patient on dose level 1 showed a partial response of 6 months in duration. Both reversible inhibition of HDJ2 farnesylation and radiosensitization of a study patient-derived cell line were demonstrated in the presence of L-778,123. K-RAS mutations were found in three of the four patients evaluated. CONCLUSIONS: The combination of L-778,123 and radiotherapy at dose level 1 showed acceptable toxicity in patients with locally advanced pancreatic cancer. Radiosensitization of a patient-derived pancreatic cancer cell line was observed.  相似文献   
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