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951.
M A Meijssen E Heineman R W de Bruin F J ten Kate R L Marquet J C Molenaar 《Transplantation》1991,51(5):955-959
The aim of this study was to evaluate the significance of in vivo measurements of electrophysiologic parameters for the detection of canine small bowel (SB) allograft rejection. In dogs of group I (n = 17) a heterotopic SB autotransplantation was performed. Dogs of group II (n = 8) received a heterotopic SB allograft in a fully mismatched donor-recipient combination. No immunosuppression was given. All grafts were monitored regularly by in vivo measurements of transepithelial potential differences (PDs) and by biopsies of the grafts. The overall technical failure rate was 36% caused by thrombosis at the vascular anastomosis in most cases. All successful autografts survived the experimental period and showed physiologic PD responses after stimulation by both a theophylline solution and a glucose solution. The successful allografts survived 5.5 +/- 0.2 days (mean +/- SEM); the transepithelial PDs showed normal responses at postoperative day 3, but showed decreased responses at day 5 (P less than 0.05) and reversed responses at day 6 (P less than 0.05). The diminished PD responses correlated well with the onset of histologic alterations characteristic of rejection. This study demonstrates that serial monitoring of transepithelial PD responses is a noninvasive method to detect acute SB allograft rejection. 相似文献
952.
Paul B Fitzgerald Zafiris J Daskalakis Kate Hoy Faranak Farzan Daniel J Upton Nicholas R Cooper Jerome J Maller 《Clinical EEG and neuroscience》2008,39(3):112-117
A number of studies using paired pulse transcranial magnetic stimulation (TMS) have demonstrated that cortical inhibition (CI) of the motor cortex can be recorded and also gauged through surface electromyography. However, recording CI from other brain regions that are more directly related with the pathophysiology of some neurologic and psychiatric disorders (e.g., dorsolateral prefrontal cortex (DLPFC) in schizophrenia) was previously fraught with technical difficulties. This study was therefore designed to examine, through a combination of TMS with EEG, whether CI could be measured directly from the motor cortex, DLPFC, and another non-motor region. To index CI, long interval cortical inhibition (LICI; a TMS paradigm) was used in the motor cortex and DLPFC in 14 healthy subjects, and in the parietal lobe in 5 of those subjects. In the motor cortex, LICI resulted in a significant suppression in mean cortical evoked activity on EEG (37.31 +/- 47.51%). In the DLPFC, LICI resulted in a significant suppression (32.45 +/- 47.86%) in mean cortical evoked activity and did not correlate with LICI in the motor cortex although they did not significantly differ. In the parietal lobe, LICI resulted in significant suppression (47.76 +/- 44.70%) in mean cortical evoked activity. In conclusion, CI in the dorsolateral prefrontal cortex, motor cortex and parietal cortex were similar at 120% of motor threshold. These data suggest that CI can be recorded by combining TMS with EEG and may facilitate future research attempting to ascertain the role of CI in the pathophysiology of several neurologic and psychiatric disorders. 相似文献
953.
Tubulin, the protein subunit of microtubules, is considered a target for antimitotic agents such as colchicine, maytansine and the vinca alkaloids vincristine and vinblastine. Of these agents, only vincristine and vinblastine have been found to have clinical utility for treatment of human neoplastic disease. The basis for therapeutic selectivity was examined in a comprehensive model in which human rhabdomyosarcomas were grown as xenografts in mice. This model has allowed a detailed examination of differences between neoplastic and non-neoplastic tissues with respect to binding, retention and metabolism of vinca alkaloids. Of note is that in tumor tissue, vincristine is tenaciously bound whereas vinblastine is not. In non-neoplastic tissue, retention of both agents is poor. The mechanisms responsible for differential retention between vinca alkaloids and between neoplastic and non-neoplastic tissues were examined. Results suggest that guanosine 5-triphosphate may be implicated in the formation and stability of vinca-tubulin complexes in tissue cytosols. Two models consistent with the data are proposed, and the significance to therapeutic efficacy is discussed. 相似文献
954.
955.
Kate Kendell 《Journal of adolescence》1987,10(4)
956.
An analysis is presented of the clinical and prognostic features of 22 patients diagnosed with diffuse well differentiated lymphocytic lymphoma at Cleveland Metropolitan General Hospital between 1974 and 1987. At presentation, the disease was usually advanced with 86% of patients having stage IV disease and 73% of patients exhibiting bone marrow involvement. Ten second malignancies were documented in 7 (32%) of our patients. The goal of treatment in our patients was palliation except in the 2 stage 1 patients. The response rate to initial treatment was 55% (15% complete), although 75% of patients ultimately responded to some form of therapy; and the mean survival was 58 months, a figure not different from historical controls. There were no differences in survival between patients given simple versus complex therapy at diagnosis or at any time during the course of their disease; and no differences in survival between complete, partial and nonresponders. 相似文献
957.
958.
P R Thomas C M Butler J Bowman N W Grieve C E Bennett R S Taylor M H Thomas 《The British journal of surgery》1991,78(2):207-209
Light reflection rheography is a simple non-invasive technique for assessing venous function in the leg. One hundred and twenty-four patients referred for venography with a clinically suspected deep venous thrombosis were investigated by light reflection rheography to determine the accuracy of the technique in diagnosing acute thrombosis. In half of the patients venography confirmed a deep venous thrombosis. Light reflection rheography had a sensitivity of 92 per cent and a specificity of 84 per cent in detecting acute thrombosis. The technique had a negative predictive value of 92 per cent in selecting those patients with no thrombosis. Light reflection rheography can be performed at the bedside or in the radiography department which makes it a suitable technique for screening patients with suspected deep venous thrombosis. 相似文献
959.
Clare E Collins Philip J Morgan Pennie Jones Kate Fletcher Julia Martin Elroy J Aguiar Ashlee Lucas Melinda Neve Patrick McElduff Robin Callister 《BMC public health》2010,10(1):669
Background
Obesity rates in adults continue to rise and effective treatment programs with a broad reach are urgently required. This paper describes the study protocol for a web-based randomized controlled trial (RCT) of a commercially available program for overweight and obese adult males and females. The aim of this RCT was to determine and compare the efficacy of two web-based interventions for weight loss and maintenance of lost weight. 相似文献960.
The objective of this pilot study was to evaluate the extent to which laparoscopic gynaecological surgery could be completed
as planned in overweight and obese patients versus patients of normal weight. A prospective surgical audit was conducted of
64 women undergoing laparoscopy for benign gynaecological conditions. Patients were grouped according to their body mass index
(BMI). The number of attempts required for successful laparoscopic entry, the ability to identify key surgical landmarks,
the ability to complete the planned surgery, the rate of conversion to laparotomy and the complication rates were recorded.
Surgery was completed as planned in 95.31% of participants. Completion rates declined with increasing BMI. Increased entry
attempts and an inability to identify key surgical landmarks were associated with increased BMI, although the sample size
was insufficient to provide any statistically significant conclusions. The overall complication rate was 6.25%. There was
a higher mean BMI in patients with a complication; however, there was insufficient data to show a significant difference.
This study suggests an association between increasing BMI and increased entry attempts for laparoscopy, increased difficulty
in surgical landmark identification and an overall reduction in completion of gynaecological laparoscopy as planned. 相似文献