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91.
James NL van der Meer AL Edwards GA Snelling SR Begg JD Esmore DS Woodard JC 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2003,49(4):454-458
The VentrAssist Implantable Rotary Blood Pump (IRBP) is a hydrodynamically suspended, electromagnetically driven, centrifugal blood pump that provides continuous flow of up to 10 L/min at 3,000 rpm. In vivo studies in sheep were conducted to assess system design and performance. Surgery involved thoracotomy with subdiaphragmatic pump placement. Cannulae were transdiaphragmatic, with inflow in the left ventricular apex and outflow anastomosed to the descending aorta. Animals had no anticoagulation or antiplatelet therapy after surgery and no prophylactic antibiotics after recovery. Twelve sheep were supported for 622 pump days. Estimated pump flow ranged from 1 to 5.5 L/min at 1,800 to 2,000 rpm using 2.5 to 4.5 W. There was no clinical evidence of hemolysis or cardiovascular, renal, or hepatic dysfunction. Adverse outcomes included kinking/disconnection of the outflow cannula caused by the graft bend relief (n = 4), which was addressed through cannula redesign. Pump electrical malfunction (n = 4), caused by a silicone potting compound, was corrected using a neutral curing potting material. Surgical/husbandry issues (n = 2) also were addressed. The VentrAssist IRBP provides high flow at low rotational speed and power consumption. Further trials are in progress in advance of in vivo studies of the safety and efficacy of the final system. 相似文献
92.
OBJECTIVE:
Inflammation plays an important role in the development of chronic lung disease (CLD), which has become a major cause of morbidity in surviving infants less than 1250 g at birth. The authors hypothesized that the progression of this inflammation and, therefore, the establishment of CLD would be decreased with the use of early prophylactic inhaled corticosteroids. Short, and long term respiratory and neurodevelopmental outcomes were also examined.DESIGN:
A double-blind, randomized placebo controlled trial.SETTING:
Level-III neonatal intensive care unit.POPULATION STUDIED:
Sixty infants less than 1250 g at birth, diagnosed with respiratory distress syndrome and requiring ventilatory support at 72 h of age were enrolled in the study.INTERVENTION:
Infants enrolled received either placebo or beclomethasone diproprionate by a metered dose inhaler, which was used in-line with the ventilator circuit while the infant was ventilated and then via a spacer until 28 days of age.RESULTS:
Thirty infants were given beclomethasone and 30 were given placebo. There were two deaths in each group. Among the surviving infants, the frequency of moderate-to-severe CLD was 17% in each study group. Mean time to extubation was not different for beclomethasone compared with placebo at 16.4 and 12.5 days (P=0.12), respectively. The requirement for intravenous corticosteroids was lower in the beclomethasone-treated group (RR 0.67, 95% CI 0.43 to 1.04), although this difference was not statistically significant. The incidence of growth failure, infection and intraventricular hemmorhage did not differ between the two groups. Long term outcomes were not different with respect to the incidence of respiratory re-admissions, cerebral palsy, developmental delay, blindness or deafness.CONCLUSIONS:
Early treatment with inhaled beclomethasone diproprionate did not reduce the incidence of CLD or decrease the duration of mechanical ventilation. The decrease in intravenous corticosteroid use was not statistically significant. Long term outcome was not affected. 相似文献93.
Personal and situational influences on drink driving and sober driving among a cohort of young adults. 总被引:1,自引:0,他引:1 下载免费PDF全文
OBJECTIVES: To compare personal and situational influences on incidents involving drink driving with those involving sober driving. METHODS: Information on a range of road safety practices was sought in face to face interviews conducted with 969 members of the Dunedin Multidisciplinary Health and Development Study cohort at age 26 years. A total of 750 study members reported an incident that involved the opportunity to consume alcohol and also travel by motor vehicle. Of these, 87 were classified as "drink drive incidents" and 663 as "sober drive incidents". RESULTS: Study members who were male, of lower socioeconomic status, had no school qualifications, or were dependent on alcohol or marijuana at age 21 were significantly more likely to report a drink drive incident at age 26. Compared with the sober drive incidents, the drink drive incidents were more commonly associated with driving alone, drinking at bars, and no advanced planning. For drink drive incidents the amount of alcohol consumed was influenced by the conviviality of the occasion, whereas for sober drive incidents it was the need to drive. One quarter of those reporting drink drive incidents stated they had used marijuana and/or LSD at the event at which they drank. CONCLUSIONS: Drink drive and sober drive incidents differed, particularly with regard to decisions made before the event. Prevention efforts could usefully be targeted toward these decisions. 相似文献
94.
95.
Ventral hernia repair: a study of current practice 总被引:5,自引:5,他引:0
Ventral wall hernias are common; despite this, there are no guidelines on the best surgical management. The aim of this study
was to examine the types of repair in use for abdominal wall hernias in the West of Scotland over a 3-month period. Data were
gathered on 120 patients. There were 60 incisional, 32 umbilical, and 28 epigastric hernias. The main indication for repair
was pain (78%), while 12 patients (10%), presented acutely with incarceration or strangulation. The most common method of
repair was sutured (55%), followed by mesh (29%) and Mayo repair (16%). There was no correlation between use of mesh and hernia
size or whether repair was for a recurrent hernia. Surgical practice varies widely in the repair of ventral wall hernias.
Clinical trials are required to establish the best method of repair for this common condition.
Electronic Publication 相似文献
96.
Background
Low grade fibromyxoid sarcomas (LGFMS) are very rarely seen. They commonly arise from deep soft tissues of the lower extremities. Very few cases of intra-abdominal location have been reported. 相似文献97.
Hay P Katsikitis M Begg J Da Costa J Blumenfeld N 《Psychiatric services (Washington, D.C.)》2003,54(7):1028-1030
A six-month cohort of general adult psychiatric inpatients was followed for up to two years to evaluate outcome and contrast the validity of DSM-IV measures of adaptive functioning-the Global Assessment of Functioning (GAF), the Social and Occupational Functioning Assessment Scale (SOFAS), and the Global Assessment of Relational Functioning Scale (GARF). Detailed data, including quality-of-life ratings and DSM-IV axis I and V codes, were collected by interview and self-report questionnaires for 53 study participants. Patients' retrospective ratings of the care they received were not predictive of outcome. Adaptive functioning at discharge was predictive of both severity of illness and social functioning at follow-up. The SOFAS had the strongest concurrent and predictive validity, the latter both for length of initial inpatient stay and two-year outcome. 相似文献
98.
Mark?RoyEmail author Clemens?Kirschbaum Andrew?Steptoe 《Annals of behavioral medicine》2003,26(3):194-200
Intraindividual variation in recent stress exposure and its impact upon cortisol and testosterone was investigated. Over 1
year, 72 young male firefighters completed the Daily Stress Inventories, for 2 shift cycles (16 days), every 3 months. At
the end of each 16-day period each participant attended a 1-hr morning assessment session. Saliva samples and blood pressure
measurements were taken at 10-min intervals, and at 30 min, a blood sample was drawn. Across the year of assessment, there
were significant linear relationships in reported stress and in neuroendocrine activity. In contrast to expectations, as daily
stress decreased across the year (p < .008), salivary cortisol increased (p < .001) and testosterone levels decreased (p <
.001). Within-subjects comparisons of the sessions with the highest and lowest stress confirmed these linear relationships:
Lower stress prior to the assessment session was associated with higher cortisol levels (p < .01). These results, though in
contrast to the orthodoxy concerning the association between stress and cortisol, are supported by findings in a number of
other studies and may constitute down regulation of cortisol activity following an increment in stress exposure.
This research was supported by the Medical Research Council, United Kingdom. We are grateful to the London Fire & Civil Defence
Authority for their cooperation. 相似文献
99.
AIM: To determine changes in numbers, demography and type of questions posed to the drug information service (DIS) at Christchurch Hospital over the last fifteen years. METHODS: The database of the DIS was used to retrieve data for one-year periods including the period of establishment in 1985/1986, 1993/1994 and 1999/2000. RESULTS: The number of questions per month increased from 26 in 1985/1986 to 284 in 1999/2000. The majority of questions have related to adverse drug reactions, contraindications/precautions, drug selection, interactions, and administration/dosage. Questions on drug interactions showed the greatest relative increase, from 8% to 19% of all questions. A disproportionate increase in requests came from primary care, which provided 14% of questions in 1985/1986 and 38% in 1999/2000. Computer databases are the major resource used currently whereas journal articles and textbooks dominated in 1985/1986. CONCLUSIONS: There has been a marked increase in use of the DIS despite a relatively constant population base. This may reflect an increased awareness of both the availability of the service and recognition of the complexity of medicines. The computer database is a useful reference source, decreasing repetition of search pathways and allowing audit to assist in the ongoing improvement of the service. 相似文献
100.
BACKGROUND: Randomized trials have established that 5-fluorouracil-based adjuvant chemotherapy following resection of stage III colon cancer reduces subsequent mortality by as much as 30%. However, the extent to which adjuvant therapy is used outside the clinical trial setting, particularly among the elderly, is unknown. METHODS: A retrospective cohort study utilizing the Surveillance, Epidemiology, and End Results/Medicare-linked database identified 6262 patients aged 65 years and older with resected stage III colon cancer. The primary outcome was chemotherapy use within 3 months of surgery, as ascertained from Medicare claims. We examined the extent to which age at diagnosis was associated with adjuvant chemotherapy usage, and we adjusted for potential confounding based on differences in other patient characteristics with the use of multiple logistic regression. All P values were two-sided. RESULTS: Age at diagnosis was the strongest determinant of chemotherapy: 78% of patients aged 65-69 years, 74% of those aged 70-74 years, 58% of those aged 75-79 years, 34% of those aged 80-84 years, and 11% of those aged 85-89 years received postoperative chemotherapy. The age trend remained pronounced after adjustment for potential confounding based on variation in patients' demographic and clinical characteristics and after exclusion of patients with any evident comorbidity (all P values <.001). CONCLUSIONS: Adjuvant chemotherapy for stage III colon cancer is used extensively, especially for patients under the age of 75 years. However, treatment rates decline dramatically with chronologic age. Because patients in their 70s and even 80s have a reasonable life expectancy, further efforts are needed to ensure that elderly patients have the opportunity to make informed decisions regarding this potentially curative treatment. 相似文献