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991.
992.
Smart nebulizers     
Smaldone GC 《Respiratory care》2002,47(12):1434-41; discussion 1441-4
Physicians are familiar with conventional nebulizers, which deliver aerosols in a relatively uncontrolled manner. As aerosol medications evolve beyond bronchodilators, the need for control of dose variability, the possibility of overdose, and the need for efficient delivery have provoked the industry to redesign aerosol delivery systems. The need to target aerosol delivery to specific lung regions has focused efforts to coordinate aerosol delivery with defined breathing maneuvers. This review summarizes the major factors affecting aerosol deposition, discusses how those factors are guiding new designs for aerosol delivery systems, and describes some examples of the improved precision and efficiency of those systems.  相似文献   
993.
Aerosolized iloprost customized for the critically ill   总被引:1,自引:0,他引:1  
BACKGROUND: Aerosolized iloprost, an inhaled synthetic analogue of prostacyclin, is an approved therapy for stage III and IV pulmonary hypertension. However, currently iloprost is delivered via a device that requires a clinically stable patient who can use a hand-held nebulizer. We designed separate aerosol delivery systems to nebulize iloprost to critically ill patients during (1) mechanical ventilation and (2) spontaneous breathing that requires a high fraction of inspired oxygen. The goal was to deliver doses similar to the currently approved high-efficiency I-neb nebulizer system. METHODS: For the intubated patient we used the high-efficiency AeroTech II jet nebulizer and a breath-actuated ventilator circuit, without humidification. For spontaneous breathing, our delivery system consisted of a Pulmanex Hi-Ox disposable oxygen mask and an AeroTech II nebulizer. With a nebulizer charge of 20 microg, the drug presented to the patient (inhaled mass) was captured on a filter and analyzed using radioactivity (technetium-99m). The accuracy of the radiolabel was quantified by directly measuring iloprost with high-performance liquid chromatography and comparing the results. A cascade impactor measured particle distribution. RESULTS: A line of identity confirmed that the radiolabel accurately represented the drug. The mean +/- SD inhaled mass was 6.02 +/- 0.87 microg (n = 5) on the ventilator and 3.77 +/- 0.46 microg (n = 5) during spontaneous ventilation. The mass median aerodynamic diameter and fine-particle fraction were 0.7 microm, 0.99, and 0.7 microm, 0.99, respectively. CONCLUSIONS: Clinically effective doses of iloprost can be delivered to patients who require high-flow oxygen or mechanical ventilation.  相似文献   
994.
The kidney is the most commonly injured urologic organ, with most injuries occurring unilaterally. We report a rare case of synchronous bilateral renal hematomas in an 87 year old restrained driver involved in a motor vehicle accident and briefly review the management of renal trauma, including the indications for operative intervention. This case demonstrates that in select cases bilateral renal injuries can be managed conservatively.  相似文献   
995.
Social validation assessment of microswitch-based programs versus interaction/stimulation conditions for persons with multiple disabilities is a practically relevant research issue that was recently addressed (Lancioni et al., 2002, 2005a). The present study extended such validation assessment by involving a new group of students with multiple disabilities and two new groups of raters: one including teacher trainees and the other parents of children with disabilities. One hundred and forty teacher trainees and eighty-four parents watched videotapes showing the use of microswitch-based versus stimulation programs for seven students. All teacher trainees and parents scored the microswitch and the stimulation conditions on a 7-item questionnaire, the same as that used in previous studies. Data showed that both groups of raters rated the microswitch condition as more positive than the stimulation condition. These results strongly support those of the previous studies. Implications for use of microswitches with persons with profound and multiple disabilities seem unequivocal. Even so, caution needs to be used until additional replications across different cultural environments are carried out. To whom correspondence should be addressed at Department of Psychology  相似文献   
996.
After serious paracetamol overdose, charcoal haemoperfusion was used to remove paracetamol from the circulation, aiming to reduce the severity of subsequent hepatic damage. Daily long-hours high-flux dialysis was given to patients with grade III-IV hepatic encephalopathy, and also to those at risk of developing encephalopathy. We reviewed patients treated in this manner who had not received N-acetylcysteine within the first 15 h after overdose. From January 1983 to January 1993, 73 patients with serious paracetamol overdose were seen, of whom 51 received charcoal haemoperfusion and/or high-flux dialysis. Patients who were admitted within the first 42 h after overdose and who received haemoperfusion and/or dialysis had significantly lower peak levels of prothrombin time, bilirubin and creatinine than those who were admitted after 42 h. Mortality was also lower amongst patients admitted before 42 h, at 2/18 (11%) vs. 15/33 (45%), <it>p</it> &lt; 0.05.   相似文献   
997.
To see if citrate-phosphate-dextrose-adenine-two (CPDA-2) anticoagulant- preservative had an effect on the viability of platelets, we studied autologous in vivo recovery and survival in humans for platelet concentrates prepared from six units of blood drawn into CPDA-2 and compared them to six units drawn into citrate-phosphate-dextrose (CPD). These units were prepared from whole blood held at room temperature for 8 hours after collection and were then stored for 3 days at 22 ± 2 degrees C. The recovery for platelets preserved in CPD was 39.0 +/0 4.8 percent and for platelets preserved in CPDA-2, 32.5 ± 4.4 percent. The difference was not significant (p greater than 0.10). In order to estimate population differences, in vitro effects on in vivo viability were also evaluated. Six in vitro variables were studied but only pH at 72 hours (r = 0.77), platelet count (r = 0.64), and morphology score (r = 0.66) correlated to recovery. Only pH at 72 hours significantly influenced recovery (p = 0.007). By adjusting for individual pH differences, mean recovery for platelets stored in CPD was 37.5 percent, and for platelets stored in CPDA-2, 34.0 percent. The mean lifespan was 6.7 ± 0.7 days for platelets preserved in CPD and 6.1 ± 1.0 days for those preserved in CPDA-2. Although hemostatic function was not studied, these data support in vitro observations that platelets preserved with CPDA-2 are not different from platelets preserved with CPD, even after 8-hours of storage of whole blood at room temperature prior to platelet concentrate preparation.  相似文献   
998.
Malignant pleural mesothelioma (MPM) is the most common primary pleural tumor and its incidence is rising. Its diagnosis, staging and response assessment are challenging for imaging. Integrated positron emission tomography (PET)/CT increases the accuracy of overall staging in patients with mesothelioma and improves the selection of patients for curative surgical resection. It is particularly useful in identifying occult distant metastases. It may be used to predict prognosis and to assess the metabolic response to therapy.  相似文献   
999.
1000.

BACKGROUND:

Core wash or touch imprint cytology is often used to obtain a quick, preliminary diagnosis on a core needle biopsy (CNB) of breast lesions, essential for the management of the 1‐day breast clinic. Contradictory results of both techniques in the literature led to this preclinical study investigating an alternative method of touch imprint and core wash cytology.

METHODS:

Thirty breast lesions were biopsied by a core needle in a laboratory setting. The CNBs were collected in RPMI fluid (Roswell Park Memorial Institute fluid). The touch imprint cytology was performed taking the biopsy out of the fluid and smearing it on a microscopic slide and May‐Grunwald Giemsa stained. The core wash cytology was made by fixating the remaining cells in Fixcyt and prepared with a liquid‐based preparation method and Papanicolaou stained. The cytologic findings were categorized into benign, atypical favoring benign, atypical, suspicious, and malignant and compared with the histologic CNB results.

RESULTS:

The CNBs showed 20 of 30 samples to be malignant, 2 to be phylloides tumors, 7 to be benign, and 1 to be unsatisfactory. Both techniques showed a sensitivity of 95% and specificity of 100%. Touch imprint yielded insufficient diagnoses (13.3%), compared with core wash (6.6%). Of the core wash cases, 86% showed a good quality versus 30% in touch imprint cytology.

CONCLUSIONS:

This preclinical study on modified touch imprint and core wash techniques led to results that were comparable to or better than those in the literature. The core wash cytology is preferred to touch imprint because of the better morphology. Cancer (Cancer Cytopathol) 2009. © 2009 American Cancer Society.  相似文献   
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