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61.
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
62.
Robert A. Weber Warren H. Proctor Michael R. Warner Charles N. Verheyden 《Microsurgery》1993,14(5):323-327
The rat sciatic nerve serves as a good model of nerve regeneration and, as such, is often used in investigations of nerve repair. After transection of the sciatic nerve, rodents frequently scratch and bite their anesthetic foot, resulting in amputation of one or more toes. This is termed autotomy or autophagy. When these rats are part of a study using the sciatic functional index (SFI), autotomy results in unusable data, since necessary foot landmarks have been removed. It would be helpful, therefore, to be familiar with the phenomenon of autotomy and to know which rats are least likely to mutilate themselves. In our experiment involving 64 rats in which the sciatic nerve was transected and repaired, we found that female Sprague-Dawley rats were significantly less likely to perform autotomy than males (33% vs. 65%, P =.04). In addition, we noted that two-thirds of the autotomies that occurred did so by postoperative week 4 and that tabasco sauce did not decrease this activity. We present our experience and a survey of the literature on autotomy and the SFI. © 1993 Wiley-Liss Inc. 相似文献
63.
We report our observation on the "empty wall" and "vertical strut" signs of anterior cruciate ligament (ACL) insufficiency. ACL tears most commonly occur in the midsubstance; arthroscopic evaluation of patients with these tears often reveals minimal evidence of previous ACL tissue along the intercondylar wall, thus giving the appearance of an "empty wall." In proximal ACL tears, the long remnant of ACL tissue may adhere to adjacent PCL tissue. Arthroscopically, one may see this vertically oriented strut of tissue, which to the casual arthroscopist may mimic a normal-appearing ACL except for orientation and tension. In addition, the "empty wall" sign will be noted because the lateral intercondylar wall becomes easily visible following ACL injury. In two separate prospective studies of 84 such patients, the combined incidence of the empty wall sign was 82%, and the incidence of the vertical strut sign was 50%. These findings should be sought for meticulously at the time of arthroscopic evaluation. The vertical strut should not be misinterpreted as an aberrantly oriented ACL or partial ACL tear. 相似文献
64.
P N Nelson P R Carnegie J Martin H Davari Ejtehadi P Hooley D Roden S Rowland-Jones P Warren J Astley P G Murray 《Molecular pathology》2003,56(1):11-18
Human endogenous retroviruses (HERVs) are a family of viruses within our genome with similarities to present day exogenous retroviruses. HERVs have been inherited by successive generations and it is possible that some have conferred biological benefits. However, several HERVs have been implicated in certain cancers and autoimmune diseases. This article demystifies these retroviruses by providing an insight into HERVs, their means of classification, and a synopsis of HERVs implicated in cancer and autoimmunity. Furthermore, the biological roles of HERVs are explored. 相似文献
65.
66.
The purpose of this study was to determine the electrical properties of the encapsulation tissue that surrounds electrodes
chronically implanted in the body. Two four-electrode arrays, fabricated from either epoxy or silicone rubber, were implanted
in each of six adult cats for 82 to 156 days.In vivo measurements of tissue resistivity using the four-electrode technique indicated that formation of the encapsulation tissue
resulted in a significant increase in the resistivity of the tissue around the arrays.In vitro measurements of tissue impedance using a four-electrode cell indicated that the resistivity of the encapsulation tissue was
a function of the tissue morphology. The tight layers of fibroblasts and collagen that formed around the silicone rubber arrays
had a resistivity of 627±108 Ω-cm (mean ± SD; n=6), which was independent of frequency from 10 Hz to 100 kHz, and was significantly
larger than the resistivity of the epoxy encapsulation tissue at all frequencies between 20 Hz and 100 kHz. The combination
of macrophages, foreign body giant cells, loose collagen, and fibroblasts that formed around the epoxy arrays had a frequency-dependent
resistivity that decreased from 454±123 Ω-cm (n=5) to 193±98 Ω-cm between 10 Hz and 1 kHz, and was independent of frequency
between 1 kHz and 100 kHz, with a mean value of 195 ±88 Ω-cm. The results indicate that the resistivity of the encapsulation
tissue is sufficient to alter the shape and magnitude of the electric field generated by chronically implanted electrodes. 相似文献
67.
Post-marketing surveillance of enalapril: experience in 11 710 hypertensive patients in general practice 总被引:1,自引:1,他引:1 下载免费PDF全文
Warren D. Cooper David Sheldon Derek Brown Graham R. Kimber Valerie L. Isitt William J.C. Currie 《The British journal of general practice》1987,37(301):346-349
Post-marketing surveillance in general practice represents an important part of the monitoring of adverse events associated with newly introduced drugs. Such a study of the angiotensin-converting enzyme inhibitor enalapril maleate has been undertaken in 11 710 patients with essential hypertension. Serious adverse events occurred in 1.7% of patients, though most of these were not thought to be related to the treatment. The incidence rates of death (0.09%), stroke (0.11%) and myocardial infarction (0.15%) were compatible with rates predicted from age, sex and blood pressure considerations. Other events reported were hypotension (0.3%), angioneurotic oedema (0.03%), rash (0.5%), taste disturbance (0.2%) and cough (1.0%). The degree of blood pressure reduction attained was similar to that previously reported from pre-marketing development studies, as was the overall nature and frequency of both serious and non-serious adverse events. The most frequently reported event during enalapril therapy was of an improvement in well-being (19.8%). 相似文献
68.
Steven F. Ziegler Karen K. Morella Dirk Anderson Noriko Kumaki Warren J. Leonard David Cosman Heinz Baumann 《European journal of immunology》1995,25(2):399-404
The interleukin (IL)-2 receptor γ chain has recently been shown to be a component of the IL-7 and IL-4 receptors. Using a transient transfection assay and the trans-activation of reporter gene constructs which are under the control of cytokine-responsive promoter elements, we have studied signal transduction through the IL-7 receptor (IL-7R). The reporter gene expression was not stimulated by receptors that contained the cytoplasmic domain of the IL-7R, either as intact IL-7R or as part of a chimeric receptor. However, co-expression of the IL-7R with the IL-2 receptor γ chain was able to stimulate gene activation. For maximal stimulation the intact cytoplasmic domains of each chain was required. 相似文献
69.
Martin DJ Warren LA Gunatillake PA McCarthy SJ Meijs GF Schindhelm K 《Biomaterials》2001,22(9):973-978
This article describes a new test method for the assessment of the severity of environmental stress cracking of biomedical polyurethanes in a manner that minimizes the degree of subjectivity involved. The effect of applied strain and acetone pre-treatment on degradation of Pellethane 2363 80A and Pellethane 2363 55D polyurethanes under in vitro and in vivo conditions is studied. The results are presented using a magnification-weighted image rating system that allows the semi-quantitative rating of degradation based on distribution and severity of surface damage. Devices for applying controlled strain to both flat sheet and tubing samples are described. The new rating system consistently discriminated between the effects of acetone pre-treatments, strain and exposure times in both in vitro and in vivo experiments. As expected, P80A underwent considerable stress cracking compared with P55D. P80A produced similar stress crack ratings in both in vivo and in vitro experiments, however P55D performed worse under in vitro conditions compared with in vivo. This result indicated that care must be taken when interpreting in vitro results in the absence of in vivo data. 相似文献
70.