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101.
Postoperative radiotherapy for locally advanced colon cancer 总被引:1,自引:0,他引:1
Dr. E. Henry Amos MD William M. Mendenhall MD Patricia J. McCarty BA John O. Gage MD J. Logan Emlet MD Gerald C. Lowrey MD Craig A. Peterson MD Warren R. Amos MD 《Annals of surgical oncology》1996,3(5):431-436
Background: The role of adjuvant postoperative radiotherapy for locally advanced colon cancer is not well documented.
Methods: Seventy-eight patients who underwent a complete resection of B2-C colon cancer received postoperative radiotherapy. Twenty-eight
patients received ⩽45 Gy; 50 patients received 50–55 Gy. Twenty-seven patients received adjuvant fluorouracil-based chemotherapy.
All patients were followed for a minimum of 3 years; no patients were lost to follow-up.
Results: The overall local control rate was 88%. The 5-year actuarial rate of local control was 96% after 50–55 Gy postoperative radiotherapy
compared with 76% after <50 Gy (p=0.0095). Multivariate analysis of local control showed that only radiotherapy dose significantly
influenced this end point. Cause-specific survival rates at 5 years were B2, 67%; B3, 90%; C1, 100%; C2, 61%; C3, 36%; and
overall, 63%. Multivariate analysis of cause-specific survival showed that only stage significantly influenced this end point.
Bowel obstruction caused by adhesions developed in three patients and required a laparotomy; radiation-induced sarcoma developed
in one additional patient.
Conclusions: Postoperative radiotherapy appears to reduce the risk of local recurrence in patients with locally advanced colon cancer.
The optimal dose is probably 50–55 Gy at 1.8 Gy per fraction. Postoperative radiotherapy may improve cause-specific survival
for patients with stages B3 and C2 cancers. 相似文献
102.
Prevention of renovascular and cardiac pathophysiological changes in hypertension by angiotensin II type 1 receptor antisense gene therapy
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Jeffrey R. Martens Phyllis Y. Reaves Di Lu Michael J. Katovich Kathleen H. Berecek Sanford P. Bishop Mohan K. Raizada Craig H. Gelband 《Proceedings of the National Academy of Sciences of the United States of America》1998,95(5):2664-2669
Hypertension produces pathophysiological changes that are often responsible for the mortality associated with the disease. However, it is unclear whether normalizing blood pressure (BP) with conventional therapy is effective in reversing the pathophysiological damage. The duration and initiation of treatment, site of administration, and agent used all appear to influence the reversal of the pathophysiological alterations associated with hypertension. We have previously established that retrovirally mediated delivery of angiotensin II type 1 receptor antisense (AT1R-AS) attenuates the development of high BP in the spontaneously hypertensive (SH) rat model of human essential hypertension. Our objective was to determine whether this attenuation of high BP is associated with prevention of other pathophysiological changes induced by the hypertensive state. Intracardiac delivery of AT1R-AS in neonates prevented the development of hypertension in SH rats for at least 120 days. Contractile experiments demonstrated an impaired endothelium-dependent vascular relaxation (acetylcholine) and an enhanced contractile response to vasoactive agents (phenylephrine and KCl) in the SH rat renal vasculature. In addition, the voltage-dependent K+ current density, which is believed to contribute to smooth muscle resting membrane potential and basal tone, was decreased in renal resistance artery cells of the SH rat. AT1R-AS treatment prevented each of these renal vascular alterations. Finally, AT1R-AS delivery prevented the pathological alterations observed in the SH rat myocardium, including left ventricular hypertrophy, multifocal fibrosis, and perivascular fibrosis. These observations demonstrate that viral-mediated delivery of AT1R-AS attenuates the development of hypertension on a long term basis, and this is associated with prevention of pathophysiological changes in SH rats. 相似文献
103.
Craig McNulty Rosamund Kissi-Deborah Imogen Newsom-Davies 《Journal of Applied Research in Intellectual Disabilities》1995,8(2):129-136
Following the increasing trend for de-institutionalisation of people with learning disabilities, community services are increasingly being utilised to support those who also display challenging behaviours. Where severely challenging behaviours are involved community service providers may require additional support from die police service. The authors undertook a retrospective pilot study among two major community care providers in South London, and looked at the reasons for calling the police, the frequency with which die police were called; staff expectations in calling the police and the outcomes for die clients in terms of further involvement with the criminal justice system. The authors note that the police were generally used as additional support when clients became too difficult for the immediate service providers to manage. It is also noted that police action on behalf of victims was generally low and that the police were never called in response to clients with learning disabilities reporting having witnessed crime. The authors note that further research is required. 相似文献
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What is the nature of the kindling process? We hypothesize that kindling is a discontinuous process involving discrete, stepwise transitions from one state of neural organization to another. Our data from the kindling antagonism paradigm argue that there are two critical transitions in the kindling process. These transitions constitute major steps in kindled seizure development. They act as "gates" controlling the ability of afterdischarge (AD) activity to effect the necessary reorganization of neural function which drives the kindling process. We identify two critical gates: 1) a forebrain gate which is dependent on norepinephrine (NE) and effects a discrete transition from nonconvulsive, stage 1 and 2 behaviors to stage 3 seizures, and 2) a brainstem gate which is also NE-dependent and effects a transition from stage 3 seizures to stage 4 and 5 seizures. These gates separate the kindling process into 3 "phases" which are different from, but overlap, the traditional behavioral stages of kindling defined by Racine. Current data suggest that these phases involve independent neural circuitry. They may also involve different physiological mechanisms, but this remains to be determined. This hypothesis is designed to provide a framework for the kindling process within which to search for kindling mechanisms. 相似文献
108.
Craig L. Hyser 《Molecular and chemical neuropathology / sponsored by the International Society for Neurochemistry and the World Federation of Neurology and research groups on neurochemistry and cerebrospinal fluid》1989,10(1):15-20
Through a process that has come to be known as reverse genetics, the gene and gene product involved in Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD) have been identified. The DMD/BMD gene is over 2 million base pairs in size and over 50% of DMD/BMD patients harbor submicroscopic deletions for portions of the gene. The gene product, named dystrophin, is 400 Kd in size. Dystrophin is present in skeletal, cardiac, and smooth muscles, as well as brain. The protein is absent or altered in DMD/BMD patient muscle. The normal function of dystrophin and the reasons why its alteration results in the DMD/BMD phenotypes are presently unknown. The discoveries to date, however, provide a starting point for investigating the fundamental pathogenetic mechanisms involved in DMD/BMD. 相似文献
109.
Stephensen CB Marquis GS Douglas SD Wilson CM 《Journal of acquired immune deficiency syndromes (1999)》2005,38(2):180-190
In a cross-sectional study involving subjects from the Reaching for Excellence in Adolescent Health cohort, we examined the associations between HIV status, disease severity, immune activation, and oxidative damage. Subjects (265 HIV-positive and 127 HIV-negative) were young (range: 14-23 years of age) and primarily female (75%) and black (67%). Many subjects, particularly female subjects, were overweight or obese. Relatively few HIV-positive subjects had advanced HIV disease (13%), and 54% were taking antiretroviral therapy (ART). The 2 markers of oxidative damage used in this study (plasma malondialdehyde and protein carbonyl concentrations) did not correlate with each other, and neither was higher in HIV-positive subjects than in HIV-negative controls. Increased oxidative damage was seen in association with male gender, cigarette smoking, marijuana use, immune activation (as indicated by activated CD8 T-cell counts and plasma C-reactive protein concentration), and use of ART, however. Plasma ceruloplasmin was associated with decreased oxidative damage in HIV-positive subjects, although this association was not seen in those taking ART. 相似文献
110.