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61.
Among breast cancer patients p53 gene mutation is associated with a poor prognosis. Young women with breast cancer are more likely than older women to have a poor prognosis, but whether p53 gene mutation plays a role in breast cancer in young women is not clear. This study identified 199 breast cancer patients and tested the hypothesis that p53 gene mutation was associated with early onset breast cancer. Patients with p53 gene mutations were 3-times more likely to have an early onset breast cancer (age < or = 40 years at diagnosis) than those without p53 mutations (OR = 3.05, 95% CI = 1.10-8.45). Patients with both missense and silent mutations were 7-times more likely to have a diagnosis of early onset breast cancer (OR = 7.56, 95% CI = 2.22-25.8). Patients with mutations in exon 8 of the p53 gene were 6-times more likely to be diagnosed with early onset breast cancer (OR = 6.48, 95% CI = 1.37-30.6). These findings suggest that p53 gene mutation may hasten the onset of female breast cancer. 相似文献
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Junctional ectopic tachycardia is recognized predominantly as a postoperative arrhythmia after surgery for congenital heart disease. Diagnosis and treatment distinguish it from more commonly observed mechanisms of supraventricular tachycardia. We present a case of junctional ectopic tachycardia that occurred in the setting of abdominal trauma caused by child abuse and then explore the significance of this arrhythmia in a patient with trauma. 相似文献
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Muralidharan V Nikfarjam M Malcontenti-Wilson C Christophi C 《World journal of surgery》2004,28(1):33-37
Interstitial laser hyperthermia (ILH) is an in situ ablative technique used to treat colorectal liver metastases. The relatively high recurrence of tumor after treatment by ILH may be related to incomplete destruction. Little is known about the effectiveness of ILH for destroying tumor microvasculature. The aim of this study was to define the changes to the microvascular architecture of tumors after treatment with ILH, specifically focusing on the completeness of tumor vasculature destruction. An intrasplenic induction model of liver metastases in 4- to 6-week-old male inbred CBA mice was used. Laser hyperthermia was applied to liver and tumor tissue using a bare optical quartz fiber from a Medilas Fibertom 4100 Nd:YAG surgical laser generator. The animals underwent microvascular corrosion casting of the livers immediately after application of ILH. Microvascular casts were then prepared and studied by scanning electron microscopy. ILH produced complete, uniform destruction of the tumor microvasculature with compete hemostasis. Blood flow in vessels larger than 100 m diameter had a relatively protective effect, although ILH was able to overcome this barrier effectively by increasing the energy applied. ILH produces complete destruction of tumor microvasculature with hemostasis. The protective effect of blood flow in larger vessels can be overcome by the appropriate use of higher energy levels. 相似文献
67.
Dawson AN Walser B Jafarzadeh M Stebbins CL 《Medicine and science in sports and exercise》2004,36(4):632-638
PURPOSE: In decerebrate cats, topical application of analgesic balm (AB) can attenuate the pressor response to electrically induced static contraction. We examined the possibility that this phenomenon also occurs in humans and determined whether such effects were limited to a local action on the contracting muscle (e.g., attenuations of the action of groups III and IV muscle afferents that cause the exercise pressor reflex) or whether they also may have affected active muscle blood flow and/or central command. METHODS: Blood pressure (mean arterial pressure (MAP)), heart rate (HR), brachial artery blood flow (BABF), and relative perceived exertion (RPE) were assessed at rest and during 90 s of static handgrip contraction before and 50 min after application of a commercially available AB (1% capsaicin, 12.5% methyl salicylate) to the skin of the forearm muscles. RESULTS: AB attenuated the MAP response to contraction (19 +/- 3 vs 27 +/- 5 mm Hg) but had no effect on the HR response. Absolute BABF was enhanced at rest and during contraction, but absolute (118 +/- 47 vs 114 +/- 47 mL x min) and percent increases (83 +/- 31 vs 55 +/-19%) were not statistically different between conditions. AB appeared to slightly enhance RPE, but this was also the case in a control protocol where only the vehicle (petroleum jelly) was used and no change in the blood pressure response was seen. CONCLUSIONS: AB attenuates contraction-induced increases in MAP that do not seem to be related to alterations in perfusion of active muscle or central command. Effects appear to be localized to the active skeletal muscle and likely involve reductions in sensitivity of groups III and IV muscle afferents to local chemical and/or mechanical stimulation. 相似文献
68.
Roghani M Baluchnejadmojarad T Vaez-Mahdavi MR Roghani-Dehkordi F 《Vascular pharmacology》2004,42(1):31-35
In this study, the mechanisms involved in vasorelaxant effect of the flavonoid quercetin was investigated in isolated aortic rings from streptozotocin (STZ)-diabetic rats. After 4 weeks, addition of quercetin (0.1 microM-1 mM) caused a significant dose-dependent relaxation of noradrenaline (NA)- and KCl-preconstricted rings in both control and diabetic groups with a significant inter-group difference of P<0.01. Furthermore, both nitro-L-arginine-methyl ester (L-NAME, 100 microM) and indomethacin (10 microM) markedly attenuated the vasorelaxant responses following quercetin application. Meanwhile, endothelium removal significantly attenuated the quercetin-induced vasorelaxation. It is concluded that the quercetin can relax the preconstricted rings of aorta in subchronic STZ-diabetic rats through nitric oxide- and -prostaglandin-mediated pathways, which themselves could be considered as endothelium-dependent. 相似文献
69.
Simultaneous integrated boost for breast cancer using IMRT: a radiobiological and treatment planning study 总被引:1,自引:0,他引:1
Guerrero M Li XA Earl MA Sarfaraz M Kiggundu E 《International journal of radiation oncology, biology, physics》2004,59(5):1352-1522
PURPOSE: The purpose of this work is to explore the possibility of using intensity-modulated radiation therapy (IMRT) to deliver the boost dose to the tumor bed simultaneously with the whole-breast IMRT to reduce the radiation treatment time by 1-2 weeks. METHODS AND MATERIALS: The biologically effective dose (BED) for different treatments was calculated using the linear-quadratic (LQ) model with parameters previously derived for breast cancer from clinical data (alpha/beta = 10Gy, alpha = 0.3Gy(-1)). A potential doubling time of 15 days (from in vitro measurements) for breast cancer and a generic alpha/beta ratio of 3 Gy for normal tissues were used. A series of regimens that use IMRT as initial treatment and an IMRT simultaneous integrated boost (SIB) were derived using biologic equivalence to conventional schedules. Possible treatment plans with IMRT SIB to the tumor bed were generated for 2 selected breast patients, 1 with a shallow tumor and 1 with a deep-seated tumor. Plans with a simultaneous integrated electron boost were also generated for comparison. Dosimetric merits of these plans were evaluated based on dose volume histograms. RESULTS: A commonly used conventional treatment of 45 Gy (1.8 Gy x 25) to the whole breast and then a boost of 20 Gy (2 Gy x 10) is biologically equivalent to an alternative plan of 1.8 Gy x 25 to the whole breast with a 2.4 Gy x 25 SIB to the tumor bed. The new regime reduces treatment time from 7 to 5 weeks. For the patient with a deep-seated tumor, the IMRT plans reduce the volume of the breast that receives high doses (compared with the conventional photon boost plan) and provides good coverage of the target volumes. CONCLUSION: It is biologically and dosimetrically feasible to reduce the overall treatment time for breast radiotherapy by using an IMRT simultaneous integrated boost. For selected patient groups, IMRT plans with a new regimen can be equal to or better than conventional plans. 相似文献
70.
Sadeghi HM Grines CL Chandra HR Mehran R Fahy M Cox DA Garcia E Tcheng JE Griffin JJ Stuckey TD Lansky AJ O'Neill WW Stone GW 《The American journal of cardiology》2004,94(5):637-40, A9
In 2,082 patients in the CADILLAC trial, the outcomes of patients presenting during peak hours were compared with those presenting during peak hours (Monday to Friday 8a.m. to 8 p.m., n = 1,047, 51%) were compared with those of patients presenting during off-peak hours (weeknights from 8 p.m. to 8 a.m. and weekends, n = 989, 49%). Although treatment times to percutaneous coronary intervention (PCI) were delayed approximately 21 minutes, in patients with acute myocardial infarctions occurring on weeknights and weekends, this modest delay did not adversely affect procedural success, myocardial recovery, or survival after PCI. 相似文献