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101.
PURPOSE: To evaluate the toxicity of partial breast irradiation (RT) using escalating doses of low-dose-rate interstitial implant as the sole adjuvant local therapy for selected T1N0 breast cancer patients treated by wide local excision. The results of a European Organization for Research and Treatment of Cancer study have demonstrated a significant local control benefit using external beam RT to 65 Gy compared with 50 Gy. Thus, the tolerance of escalating doses of partial breast RT should be determined, because this approach may become a standard treatment for patients with early-stage breast cancer. METHODS AND MATERIALS: Between 1997 and 2001, 48 patients with T1N0M0 breast cancer were enrolled into an institutional review board-approved Phase I/II protocol using low-dose-rate brachytherapy implants after wide local excision and lymph node staging surgery. Brachytherapy was started 3-4 days after surgery at a dose rate of 50 cGy/h, using (192)Ir sources evenly spaced to cover 3 cm around the resection margins. Typically, 2-3 planes were used, with a median of 14 catheters (range 10-16). The total dose was escalated in three groups: 50 Gy (n = 19), 55 Gy (n = 16), and 60 Gy (n = 13). The implant volume was calculated and used to classify patients into quartiles: 76-127 cm(3) (n = 12), 128-164 cm(3) (n = 12), 165-204 cm(3) (n = 12), and >204 cm(3) (n = 12). Cosmesis, patient satisfaction, treatment-related complications, mammographic abnormalities, rebiopsies, and disease status were recorded at each scheduled patient visit. RESULTS: The median follow-up for all patients was 23.1 months (range 2-43). Very good to excellent cosmetic results were observed in 91.8% of patients. Ninety-two percent of patients were satisfied with their cosmetic outcome and said they would choose brachytherapy again over the standard course of external beam RT. Six perioperative complications occurred: two developed bleeding at the time of catheter removal, two had abscesses, one developed a hematoma, and one had a nonhealing sinus tract requiring surgical intervention. Significant fibrosis (moderate-to-severe scarring and thickening of the skin and breast) was noted in only 4 patients; 1 had received 55 Gy and 3 had received 60 Gy. Abnormal posttreatment mammograms were seen in 19 patients. Eight patients underwent rebiopsy for abnormalities found either by mammography or on physical examination; all proved to be fat necrosis or post-RT changes. The rebiopsy rates appeared to correlate with doses >/=55 Gy (6 [75%] of 8 compared with 29 [60%]of 48 overall) and implant volumes >/=128 cm(3) (7 [87.5%] of 8 compared with 36 [75%] of 48 overall). To date, no local, regional, or distant recurrences have been observed. CONCLUSION: Low-dose-rate implants up to 60 Gy were well-tolerated overall. With an implant dose of 60 Gy, the incidence of posttreatment fibrosis (25%) appeared to be increased. Only the long-term follow-up of this and other implant studies will allow an understanding of the total radiation dose necessary for tumor control and the volume of breast that requires treatment.  相似文献   
102.
We investigated the effect of the water extract of the dried flowers of Hibiscus sabdariffa L. and Hibiscus anthocyanins (HAs) (which are a group of natural pigments occurring in the dried calyx of H. sabdariffa) on paracetamol-induced hepatotoxicity in rats. The water extract was given in lieu of drinking water for 2, 3 or 4 consecutive weeks, and the HAs were given orally at doses of 50, 100 and 200 mg/Kg for five consecutive days. Paracetamol was given orally at a dose of 700 mg/Kg to induce hepatotoxicity at the end of the water extract and Has treatments. Six hours thereafter the rats were killed and their liver function evaluated biochemically and histologically. Given for 4 weeks (but not for 2 or 3 weeks) the extract significantly improved some of the liver function tests evaluated, but did not alter the histology of the paracetamol-treated rats or the pentobarbitone-induced sleeping time. At a dose of 200 mg/Kg, the hepatic histology and the biochemical indices of liver damage were restored to normal. Lower does were ineffective. Pending more evaluation for safety and efficacy, the HAs can potentially be used in mitigating paracetamol-induced hepatotoxicity.  相似文献   
103.
This study concerned the effect of swim stress on imipramine-induced antinociception in mice. The data showed that intraperitoneal (i.p.) administration of different doses of imipramine (10-40 mg/kg) and 0.5-3 min of swim stress (17 degrees C) induced antinociception in the first and second phases of the formalin test. Low period of swim stress (10 s) with low doses of imipramine (2.5, 5 and 10 mg/kg i.p.), which did not have any effect by themselves, in combination showed antinociception in the second phase of the test. Either yohimbine (0.5 mg/kg i.p.) or naloxone (1 mg/kg i.p.) reversed the response induced by the combination of low doses of imipramine plus swim stress. Yohimbine (1 mg/kg i.p.) decreased the response of imipramine (20 mg/kg i.p.) but not that of 30 s swim stress in the second phase. However, naloxone (1 mg/kg i.p.) reduced the antinociception induced by imipramine (20 mg/kg i.p.) or 30 s swim stress in the second phase of the test, the combination of imipramine with swim stress was not altered by yohimbine or naloxone. Prazosin induced antinociception by itself in the first phase of the test and increased swim-stress-induced antinociception with no interaction. It is concluded that antinociception induced by imipramine in the second phase of formalin test may be mediated through alpha(2)-adrenoceptor antagonists. The results indicate that the responses of swim stress and imipramine may be mediated by an opioid mechanism, but the combination of both drugs induced higher antinociceptive effects.  相似文献   
104.
BACKGROUND: To compare patients' satisfaction, health related quality of life, and sexual function among women who were either treated with rollerball endometrial ablation or abdominal hysterectomy with conservation of at least one ovary for the treatment of menorrhagia. METHOD: Between March 1992 to June 1997, 91 women underwent rollerball endometrial ablation and 78 women had abdominal hysterectomy with preservation of at least one ovary for the treatment of intractable menorrhagia. Each was sent a detailed questionnaire at least 18 months (range 18-60) after surgery. Case notes were reviewed to collect additional data relating to pre-operative management and operative details. RESULTS: Of 169 women, 120 (71%) returned a completed questionnaire [80/91 women (88%) had ablation and 40/78 women (51%) had hysterectomy]. Non-response analysis did not reveal any differences in prognostic characteristics between responders and non-responders. The length of hospital stay and time taken to return to normal daily activity were significantly less in the ablation group. Pre-menstrual symptoms improved over time but more so in the hysterectomy group, who also rated their improvement in general health higher. Women who had hysterectomy were more satisfied (100% versus 79%) and would be more likely to recommend it to a friend (100% versus 91%). CONCLUSION: Both procedures are effective for the treatment of menorrhagia but hysterectomy is associated with better general health and fewer pre-menstrual symptoms. Rollerball ablation is a useful alternative with many short term benefits and acceptable satisfaction rate. Further work is required to evaluate long term effects.  相似文献   
105.
106.
Various integrins are thought to be intimately involved in several pathological processes, including cancers (solid tumors and metastasis), cardiovascular diseases (stroke and heart failure), inflammatory diseases (rheumatoid arthritis) and ocular pathologies. The mechanism of the involvement of integrins in these acute and chronic disease states is slowly being elucidated. Recently, various therapeutic candidates, including antibodies, cyclic peptides and peptidomimetics, have been clinically evaluated and have been shown to successfully modulate certain disease processes. This review focuses on the key role of the alpha(v) integrin (alpha(v)beta(3)) in the angiogenic processes in diseases such as cancer, restenosis following percutaneous transluminal coronary angioplasty, stroke, ocular disease and rheumatoid arthritis.  相似文献   
107.
Starting with lead compound 2, we sought to increase the selectivity for alpha(v)beta(3)-mediated cell adhesion by examining the effects of structural changes in both the guanidine mimetic and the substituent alpha to the carboxylate. To prepare some of the desired aminoimidazoles, a novel reductive amination utilizing a trityl-protected aminoimidazole was developed. It was found that guanidine mimetics with a wide range of pK(a)'s were potent antagonists of alpha(v)beta(3). In general, it appeared that an acylated 2-aminoimidazole guanidine mimetic imparted excellent selectivity for alpha(v)beta(3)-mediated adhesion versus alpha(IIb)beta(3)-mediated platelet aggregation, with selectivity of approximately 3 orders of magnitude observed for compounds 3g and 3h. It was also found in this series that the alpha-substituent was required for potent activity and that 2,6-disubstituted arylsulfonamides were optimal. In addition, the selective alpha(v)beta(3) antagonist 3h was found to be a potent inhibitor of alpha(v)beta(3)-mediated cell migration.  相似文献   
108.
Four patients with tyrosinemia type 1 (ages 6–32 months) were treated with 2-(2-nitro-4-trifluoro-methylbenzoyl)-1,3-cyclohexandion (NTBC) at Cairo University Children’s Hospital, Egypt and followed up for 12–27 months. The recommended average dose of NTBC is 1 mg/kg/day. They were started on the following doses: 0.8, 0.58, 0.5, and 0.625 mg/kg/day, respectively. Two months after start of therapy, succinylacetone was undetectable in patients 1, 2, and 4, while in case 3, it was 5.4 μM. Her NTBC dose was increased from 0.5 to 0.65 mg/kg/day, and succinylacetone was undetectable 1 month later. They were kept on NTBC doses ranging from 0.55 to 0.65 mg/kg/day. These doses allowed catch up growth, normalization of synthetic liver functions, steep drop in serum alpha fetoprotein, reduction in phosphate loss in urine, normalization of serum calcium, phosphate, and alkaline phosphatase, and healing of active rickets. Succinylacetone was undetectable in urine on these doses. In conclusion: Doses of NTBC, lower than recommended, may be helpful in treatment of tyrosinemia, on condition that succinylacetone production is suppressed, and AFP is maintained normal or showing a progressive decrease. This cost-effective dose may allow treatment of affected children from economically underprivileged countries, but longer follow up periods are needed.  相似文献   
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