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991.
The severity of illness in transplant patients and the complexity of transplant operations results in significant postoperative morbidity and mortality. Remarkable efforts have been made by transplant physicians to study and improve organ allocation, graft and patient survival, immunosuppression and the long-term management of post-transplant complications. Less effort has been spent studying the actual transplant operation and systems of acute transplant care. The National Surgical Quality Improvement Program (NSQIP) has provided a standardized approach to quality improvement and has demonstrated significant potential for a reduction in postoperative morbidity and mortality in other surgical disciplines. Medical centers are under increasing pressure to measure surgical quality and the nexus of transplant surgical quality improvement should not lie in the hands of CMS or JACHO, but rather it should be created and developed within the transplant community. The time has come for a national transplant surgical quality improvement program based on the NSQIP infrastructure. Such a proactive approach toward quality improvement from the transplant community is an excellent investment for patients, providers and health care payers.  相似文献   
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The pharmacokinetics (PK) of moxifloxacin in healthy white New Zealand rabbits was studied following intravenous (IV) and subcutaneous (SC) administration routes as well as a SC long‐acting poloxamer 407 gel formulation (SC‐P407). Moxifloxacin concentrations were determined by high‐performance liquid chromatography assay with fluorescence detection. Mean half‐life for IV, SC and SC‐P407 routes was 2.15, 5.41 and 11.09 h. Clearance value after IV dosing was 0.78 l/kg/h. After SC administration, the mean absolute bioavailability was 117% and the Cmax was 1.61 ± 0.49 mg/l. After SC‐P407 administration, the bioavailability was 44% and the Cmax 1.83 was ±0.62 mg/l. No adverse effects were observed in any of the rabbits following IV, SC and SC‐P407 administration of moxifloxacin. Minimal inhibitory concentrations of moxifloxacin against different strains of Staphylococcus aureus from different european countries were used to compute the main pharmacodynamic (PD) surrogate markers of efficacy. The high tolerability of this SC‐P407 formulation and the favourable PK behaviour such as the long half‐life, acceptable bioavailability and excellent PK–PD ratios achieved indicate that it is likely to be effective in rabbits.  相似文献   
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SETTING: Diabetes mellitus is a known risk factor for tuberculosis (TB), but no studies have been reported from South-East Asia, which has a high burden of TB and a rapidly growing prevalence of diabetes. OBJECTIVE: To examine if and to what extent diabetes is associated with an increased risk of TB in an urban setting in Indonesia. DESIGN: Case-control study comparing the prevalence of diabetes mellitus (fasting blood glucose level >126 mg/dl) among newly diagnosed pulmonary TB patients and matched neighbourhood controls. RESULTS: Patients and control subjects had a similar age (median 30 years) and sex distribution (52% male), but malnutrition was more common among TB patients (median body mass index 17.7 vs. 21.5 kg/m2). HIV infection was uncommon (1.5% of patients). Diabetes mellitus was present in 60 of 454 TB patients (13.2%) and 18 of 556 (3.2%) control subjects (OR 4.7; 95%CI 2.7-8.1). Adjustment for possible confounding factors did not reduce the risk estimates. Following anti-tuberculosis treatment, hyperglycaemia reverted in a minority (3.7%) of TB patients. CONCLUSION: Diabetes mellitus is strongly associated with TB in young and non-obese subjects in an urban setting in Indonesia. This may have implications for TB control and patient care in this region.  相似文献   
997.
PURPOSE: Despite general worldwide acceptance of the concept of neurological determination of death (NDD), inconsistencies in clinical criteria and ancillary testing requirements remain. Numerous guidelines for NDD may be applied in clinical practice by a variety of medical practitioners, but the scientific rationale for specific guideline recommendations often remains unclear. This review examines the evolution of NDD, and seeks to provide scientific validation for existing NDD criteria. SOURCE: English language peer-reviewed medical journals and established contemporary medical texts. PRINCIPAL FINDINGS: Currently published guidelines appear to have evolved from the work of the ad hoc Committee of the Harvard Medical School to Examine the Definition of Brain Death. The Conference of the Royal Colleges and Faculties of the United Kingdom refined the criteria and subsequently adopted the principal of brainstem death. While the fundamentals of NDD guidelines are remarkably consistent worldwide, specific criteria and requirements are often inconsistent. CONCLUSION: Numerous controversies regarding NDD continue to exist, necessitating further scientific clarification of these issues. More recently published guidelines representing the collective opinion of world experts in NDD based upon best current scientific evidence are available in current medical journals.  相似文献   
998.
BACKGROUND: Changes in the hypothalamic-pituitary-adrenal (HPA) axis, as evidenced by patterns of cortisol secretion, have been of interest in understanding depression and anxiety disorders across the life span. Previous studies of pediatric depression have pointed to the period around sleep onset as a key time point for observing alterations in cortisol secretion associated with affective disorders. Evidence also indicates that pubertal development may influence the expression of HPA dysregulation. We hypothesized that adolescents with depression and youth with anxiety disorders exhibit elevated peri-sleep-onset cortisol. METHODS: Plasma cortisol was sampled every 20 min around sleep onset from children and adolescents with major depressive disorder (n = 116), anxiety disorders (n = 32), or no history of psychiatric disorder (control; n = 76). Sleep onset was determined by polysomnography. Classification of participants as children or adolescents was based on Tanner staging of pubertal maturation. RESULTS: Children with anxiety disorders had higher peri-sleep-onset cortisol than children with depression or control children. Adolescents with depression had marginally higher peri-sleep-onset cortisol than control adolescents and significantly higher peri-sleep-onset cortisol than children with depression. CONCLUSIONS: Depression and anxiety are associated with altered cortisol secretion around sleep onset, and these changes appear to be influenced by pubertal maturation.  相似文献   
999.
OBJECTIVE: Cervical nerve root stimulation (CRS) is a technique of assessing the proximal segments of motor axons destined to upper extremity muscles. Few studies report normal values. The objective was to determine CMAP onset-latencies and CMAP amplitude, area, and duration changes in healthy controls for the abductor pollicis brevis (APB), abductor digiti minimi (ADM), biceps, and riceps muscles. In addition, to determine the tolerability of CRS, as measured by the visual analog scale (VAS). METHODS: We studied 21 healthy volunteers prospectively with CRS using four target muscles (APB, ADM, biceps, and triceps) bilaterally. Collision studies were used in all APB recordings. VAS was obtained in all subjects. RESULTS: Mean CMAP onset-latencies were: APB 14 +/- 1.5 ms; ADM 14.2 +/- 1.5 ms; biceps 5.4 +/- 0.6 ms; triceps 5.4 +/- 1.0 ms. Onset-latency significantly correlated with height for all nerves. The mean change in CMAP amplitude and area (%) between most distal stimulation and CRS was: APB reduction of 15.1 +/- 11.6 and 4.9 +/- 3.6%; ADM reduction of 21.1 +/- 10.7 and 17.2 +/- 8.8; biceps reduction of 10 +/- 11.5 and reduction of 8.7 +/- 6.8; triceps increase of 3.3 +/- 5.2 and 11.0 +/- 9.9% respectively. Mean CMAP duration change between most distal stimulation and CRS was: APB, increase of 20.4 +/- 7.4%; ADM, increase of 14.4 +/- 8.5%; biceps, increase of 13.9 +/- 10.8%; triceps, increase of 7.7 +/- 6.7%. The mean VAS score was 3.8 +/- 1.2, and all subjects completed the study. CONCLUSIONS: The present study establishes normative data and indicates that CRS is a well-tolerated technique. SIGNIFICANCE: The normal values may be used as reference data for the needle CRS technique in the assessment of proximal conduction abnormalities.  相似文献   
1000.
OBJECTIVE: The application of intensity thresholds for embolus detection with transcranial Doppler (TCD) can exclude from analysis an unrecognized proportion of high-intensity transient signals (HITS))whose intensities are below the threshold. The lack of consistent threshold criteria between clinical trials may explain part of the discrepancy in the reported HITS counts. We investigated the effect of choosing different thresholds on the sensitivity and specificity of detecting HITS during cardiopulmonary bypass (CPB). METHODS: Two observers independently analyzed TCD recordings from 8 patients under CPB. Doppler signals were classified as true HITS, equivocal HITS, artifacts, and Doppler speckles according to preestablished criteria. The relative intensity of Doppler signals was measured by two different methods (TCD software vs manual). Receiver Operating Characteristic curves determined the optimal threshold for each of the two intensity methods. RESULTS: Reviewers achieved agreement in 96% of 2190 Doppler signals (kappa = 0.90). Relative intensities calculated with the TCD-software method were 3 dB (95% CI: 3.0-3.4) higher than the manual method. The optimal threshold was found at 10 dB (sensitivity: 99%; specificity: 90.8%) with the software method and at 7 dB with the manual method (sensitivity: 96%; specificity: 83%). The use of an intensity threshold 2 dB higher than the optimal increased the rejection of true HITS by 8% and 14%, respectively. CONCLUSIONS: Using intensity thresholds higher than the optimal for embolus detection decreases HITS counts. Choosing a threshold depends on the type of method used for measuring the signal intensity. Uniform threshold criteria and comparative studies between different Doppler devices are necessary for making clinical trials more comparable.  相似文献   
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