A fluidic-controlled, miniature respirator with a new positive airway pressure device

Previous studies using immunofluorescence and autoradiography demonstrated the presence of specific immunoglobulin E (IgE) receptors on rat mast cells (RMC). This finding was confirmed by the use of transmission electron microscopy (TEM) combined with X-ray microanalysis (XMA) employing ferritin labelled antisera XMA was used to detect ferritin as Fe in the target cells. On examination by TEM and XMA, 25 per cent of RMC showed a dense area of Fe deposits on the surface of the cells. No Fe could be detected on neutrophils or eosinophils or in the control cell preparations without human IgE. The Fe was concentrated in well-defined areas of the treated mast cells and this distinct concentration of receptor sites was similar to that observed by other investigators who have termed this phenomenon, "cap" formation.     

Basic performance of a miniature intraventricular axial pump

Lubeluzole is a neuroprotective compound in the final stages of clinical evaluation. We evaluated the effects of intravenous followed by intraperitoneal doses of lubeluzole on histological outcome after reversible tandem middle cerebral/common carotid artery occlusion in Long-Evans rats, with particular emphasis on the time window of efficacy. Lubeluzole, started 15 min after the onset of ischemia, had no adverse physiological or behavioral effects and reduce maximal infarct volume produced by 120 min or more of arterial occlusion by approximately 50%, from 143.2 +/- 11.8 mm3 (p < 0.05). Lubeluzole did not prolong the duration of middle cerebral artery occlusion which could be tolerated before histological damage occurred. Lubeluzole was still effective if started 30 min after the onset of ischemia (34% reduction of maximal infarct volume; p < 0.05), but not after delays of 60 or 120 min. we conclude that lubeluzole has promise as a neuroprotective drug, particularly for more severe strokes, but must be started very rapidly after the onset of ischemia to be effective.     

Vacuum pack technique of temporary abdominal closure: a four-year experience

The purpose of this review is to present a 4-year experience with the vacuum pack technique of temporary abdominal closure. From April 1992 to December 1996, 171 vacuum packs were performed on 93 patients. Eighty-seven vacuum packs were performed on 38 general surgical patients, and 84 vacuum packs were performed on 55 trauma patients. Overall hospital mortality was 32 per cent. Methods of achieving permanent wound closure varied in 73 patients. Four patients (4.3%) developed enterocutaneous fistulae; four patients developed intra-abdominal abscesses (4.3%). There were no eviscerations. Management of the complicated intra-abdominal process is discussed: 1) the decision to manage the abdomen in an open fashion; 2) which method of temporary closure to use; 3) subsequent explorations; 4) when the abdomen should be closed; 5) which type of closure to use; and 6) when the abdominal wall should be revised (herniorrhaphy). The vacuum pack is the method of choice for open abdomen management and temporary abdominal closure at our institution. With careful subsequent management, good patient outcome can be achieved.     

Team assessment utilizing a many-facet Rasch model

As organizations begin to implement work teams, their assessment will ultimately reflect compensation strategies that move away from individual assessment. This will involve not only using multiple raters, but also the use of multiple criteria. Team assessment using multiple raters and multiple criteria is therefore necessitated; however, this can produce differences in ratings due to the leniency or severity of the individual team raters. This study analyzed the ratings of individual members on 31 different teams across 12 different criteria of team performance. Utilizing the many-facet Rasch model, statistical differences between the teams and 12 criteria were calculated.     

Characteristics of electric arc furnaces powered by a low-frequency alternating current

The changes in the parameters of a DSP-100 electric arc furnace that are induced by a decrease in the current frequency are considered. It is shown that the related decrease in the current lead resistances causes an increase in the arc power and voltage, a decrease in the reactive power, and an increase in the electrical efficiency and the power coefficient. The heat indices are expected to be significantly improved.     

两级水解酸化-FCR系统处理印染废水

采用两级水解酸化-FCR系统处理印染废水,考察了不同水力停留时间(HRT)对COD、色度、NH₃-N和苯胺等去除效果的影响,并对最佳水力停留时间时脱氮效果进行了研究.结果表明:当HRT为30h时,系统COD、色度、TN、NH₃-N和苯胺的平均去除率分别为93.3%、81.9%、79.9%、98.1%和74.8%,出水满足《GB 4287-92纺织染整工业水污染物排放标准》的一级标准.该系统具有较高的去污脱色效果,脱氮效果尤其显著,可应用于中、高浓度印染废水的处理.     

微小型硬质合金工作辊的研究

微小型硬质合金工作辊的生产工艺比较繁长,它包括粉末的选择、冷成型、机加工、预烧结、热等静压处理、研磨加工等一系列工艺过程。该工艺于1994年底通过部级鉴定。本文重点叙述各阶段内容及研制过程中的工艺特点。     

Porcine islet xenotransplantation utilizing a vascularized bioartificial pancreas

Successful pancreas/islet transplantation restores normal glucose metabolism in patients with insulin dependent diabetes mellitus (IDDM) but requires chronic immunosuppression which is associated with morbidity and mortality. Immune exclusion devices containing pancreatic islets (bioartificial pancreas) are designed to provide glycemic control without immunosuppression. The immune exclusion is achieved by separating islets from the host by semipermeable membranes. Small molecules such as glucose, insulin and nutrients pass through, whereas immune lymphocytes and immunoglobulins are excluded by the membrane and unable to cause destruction of the islets. Use of xenogeneic islets (i.e., porcine islets) in the device also circumvents the shortage of human donor organs. This report provides a brief summary of our experience with vascularized bioartificial pancreas (VBAP) containing allogeneic and xenogeneic islets for treatment of experimental diabetes in dogs and describes our plans for a clinical trial of the VBAP in patients with IDDM.     

A clinical trial of the INTERPLAK powered toothbrush in a geriatric population

This study was conducted to test the effectiveness of the counter-rotational powered toothbrush in a nursing home environment. A group of 60 nursing home patients were selected; each was assigned to a specific trained toothbrusher. Participants were divided into two groups stratified by gingival inflammation in a crossover-design clinical trial. Each individual used the powered brush for one 4-week period, and a manual or conventional brush for another 4-week period. A suitable period of nonintervention separated the two 4-week periods of intervention to allow plaque and gingival scores to revert to baseline. The participants were evaluated for plaque and gingivitis before and after each brushing period. The experimental brush reduced both plaque and gingivitis more effectively than the conventional brush. The mean reduction in plaque scores was 1.44 for the conventional brush, 1.92 for the powered brush (Quigley-Hein Plaque Index). The mean reduction in gingival inflammation scores was 0.47 for the conventional brush, and 0.77 for the experimental brush (L?e and Silness Gingival Index). Participants perceived the counter-rotational powered brush to be more effective, and at the exit interview overwhelmingly preferred to keep it rather than the conventional brush.     

Drafting a parenteral nutrition order form utilizing a physician assessment process

The utilization of a physician critique process in the design of a parenteral nutrition order form, encouraging a standard order option, is assessed. In the critique process, physicians from surgery, medicine, and medical intensive care teams were tasked to use the draft order form and guideline sheet to prescribe a parenteral nutrition order for a hypothetical patient. Prescriber recommendations and problems with the nutrition order form and guideline sheet directed editorial improvements. The physician assessment process is an effective means to measure utility of a draft parenteral order form and prescribing guideline sheet. By utilizing physician expertise, deficiencies inherent in such an order form may be corrected prior to implementation.     

两段碳还原处理铬渣的工艺实践

利用C和CO的还原性，能有效地将Cr^6 还原成Cr^3 或者金属Cr．韶钢利用烧结、炼铁工艺，有效地回收和利用铬渣中的有效成分，同时利用烧结炼铁工艺中的C和CO在高温下的还原反应，达到解毒目的，实现铬渣的资源化和无害化．     

A battery powered operating table with a removable stationary column base and a detachable table top

The development of a program to monitor the use of pharmacy personnel is described. The program is part of a hospital-wide Labor Information System developed to support requests for additional staff, to highlight opportunities for improved and allocation of manpower, and to serve as a conceptual model of the department from a manpower perspective when communicating with other members of the hospital organization. Nine major functions of the pharmacy department were identified. Detailed activities for each function were listed along with the type of personnel who performed each activity. Standards representing the amount of time spent on each activity were then developed. Variable, fixed, and open standards were used. Workload volumes are tabulated on a biweekly basis and entered into a computer. Payroll data covering the same period are simultaneously fed into the computer system. The resulting computer-generated report compares the service hours necessary to perform the actual workload (based on the predetermined time standards) to the available hours actually worked by each job category of pharmacy personnel. The ratio of service hours to available hours measures the use of personnel by functional activity. The system has been successfully applied to support requests for additional personnel, to forecast staffing needs for new programs, and to make operational improvements. In addition, the system has the capacity to accurately monitor personnel time for providing clinical services.     

Long-term biocompatibility of a miniature stimulator implanted in feline hind limb muscles

Chronic foreign-body responses and muscular changes were examined following the implantation of active miniature stimulators into the hind limb muscles of cats for periods of up to three months. The radio-frequency (RF)-powered stimulators were injected into muscles through a 12-gauge hypodermic needle. The tissue responses around the active stimulators were compared histologically to those provoked by passive devices, broken glass, silicone tubing, polyester suture material coated with polybutylate, and two of the internal components of the stimulator (ferrite, integrated circuit chip). Active and passive stimulators produced similar, benign foreign-body reactions that resulted in an essentially identical fibrous capsule over time. The responses were similar to those produced by the internal components and the suture material, and were more modest than those produced by the broken glass. The capsule did not appear to interfere with the functionality of active devices because thresholds measured during the post-implantation survival period did not change significantly over time. Unexpectedly, the severity of the reaction differed significantly amongst the various target muscles. Medial gastrocnemius exhibited the most severe response, whereas tibialis anterior had the least reaction.     

HYOMEX: a miniature universal testing machine for in vivo biomechanical studies

A miniaturized universal testing machine, HYOMEX, designed for biomechanically testing spinal structures of an anaesthetized research animal, such as a pig, is presented. A variety of mechanical applications such as static and dynamic tests, creep and relaxation tests, and fatigue tests with frequencies up to 20 Hz are possible. The system permits force control as well as displacement control. Continuous surveillance is made possible through interfacing the system to a computer. An application is presented where the viscoelastic behaviour in a porcine lumbar spine was measured.