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81.
Efficacy of botulinum toxin type B (BoNT B) for the treatment of type A-resistant (AR) and non-A-resistant (NAR) cervical dystonia (CD) has been demonstrated in several single injection studies. There is little data available on long-term therapy with repeated injection sessions and it is unknown if AR and NAR patients respond in a similar manner over time. To evaluate the long-term efficacy and safety of BoNT B in AR and NAR CD patients, we carried out a prospective, open-label study examining 10 repeated dosing sessions of BoNT B in 34 patients with CD (15 AR and 19 NAR). Dosing was started at 10,000 units and could be increased to 25,000. Assessments included the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) and a patient global assessment at each baseline (injection) and Week 4 (peak effect) visit. Change in TWSTRS total was the primary efficacy end point. Data was analyzed using repeated-measures analysis of variance. BoNT B therapy resulted in an overall significant improvement of CD (P<0.001) and improvement was seen in all 10 individual sessions (2.5 years). The magnitude of response decayed over time (P<0.001). There was no difference between AR and NAR patients with regard to dose, treatment effect, or decay in response. The AR group perceived (patient global) treatment as being less effective (P=0.047). Dry mouth frequency decreased with each session despite increasing doses whereas flu-like syndrome and weakness increased. BoNT B therapy provides long-term benefit for CD patients but the magnitude of response diminishes over time. The cause of this decay is probably multifactorial. AR and NAR CD patients respond in a similar fashion.  相似文献   
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R Forman  S Cho  S M Factor  E S Kirk 《Circulation》1983,67(1):117-124
In this study we quantitated the region of preserved myocardium between a subendocardial myocardial infarct (SEMI) and the endocardium in dogs and determined whether this preserved zone was within the region at risk and whether infarct extension could occur in this region. We also evaluated whether a similar subendocardial region exists in patients with SEMI. A 40-minute temporary occlusion of the left anterior descending coronary artery (LAD) in eight dogs resulted in a 35 +/- 5% transmural infarct with 8 +/- 1% subendocardial preservation as assessed by point-counting of the histologic specimens. In vivo perfusion of coronary vessels with Microfil showed that this preserved subendocardial zone was within the region at risk. The preserved subendocardial zone had significantly fewer cell layers in the dogs ventilated with room air than in dogs ventilated with 100% oxygen (8 +/- 4 vs 19 +/- 4, p less than 0.001), which suggests that diffusion from the ventricular cavity was the mechanism of cell preservation. In contrast, the inspired oxygen concentration did not influence the size of the SEMI. Reocclusion of the LAD for 24 hours in an additional eight dogs, 1 week after a SEMI had been created by a 40-minute temporary occlusion, resulted in both subendocardial and subepicardial extension involving 5 +/- % and 29 +/- 9%, respectively, of the transmural myocardium at the infarct center. Subendocardial infarct extension of a similar dimension to that in dogs ventilated on 100% oxygen was observed in postmortem material from eight patients with infarct extension. The preserved layers of subendocardium presumably receive sufficient nutrients from the ventricular cavity to maintain the viability of this region during temporary, but not permanent, reduction of blood supply from the coronary arteries.  相似文献   
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Lymphoblasts in bone marrow samples, obtained from 43 children with acute lymphoblastic leukemia at diagnosis, were incubated with 1.0 mumols/L [3H] methotrexate for 24 hours in vitro. Nonexchangeable methotrexate and methotrexate polyglutamates were separated and quantitated. Event-free survival at 5 years was 38% +/- 9% for all 43 patients (27 failures), and 44% +/- 10% for the 35 with non-T, non-B- cell acute lymphoblastic leukemia (20 failures). Of these 35 children, those whose lymphoblasts accumulated more than 100 pmol methotrexate and 500 pmol methotrexate polyglutamates per billion cells experienced better 5-year event-free survival than those whose lymphoblasts did not (65% +/- 12% v 22% +/- 9%, P = .010). This difference characterized "good-risk" patients who were female (P = .014), less than age 7 at diagnosis (P = .005), or had low initial white blood cell counts (less than 20 X 10(9)/L, P = .018). Findings were similar for the 43 children with acute lymphoblastic leukemia and for the "good-risk" children in this total group. Thus, the ability of lymphoblasts to accumulate methotrexate and form methotrexate polyglutamates may be important to the curative properties of current therapy of acute lymphoblastic leukemia in children, particularly for "good-risk" patients. In such patients, inherent rather than acquired drug resistance may be the initial event leading to treatment failure.  相似文献   
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目的:研究Visumax飞秒激光辅助的准分子激光原位角膜磨镶术(LASIK)术中不透明气泡层(OBL)产生的类型、相关影响因素及其临床意义。方法:回顾性分析。收集2016 年7 月1 日至8 月20 日在南京医科大学附属眼科医院行飞秒LASIK的患者154 例(300 眼)的临床资料,等效球镜度为(-5.88±1.51)D。飞秒激光采用Zeiss公司 Visumax飞秒激光仪,将术中产生的OBL分为瓣外OBL、瓣内快速OBL和瓣内慢速OBL。300 眼按角膜曲率平均K值分为A组(<42 D)、B组(42~46 D)和C组(>46 D);按角膜瓣的厚度分为D组(100 μm)、E组(110 μm)和F组(120 μm);按角膜厚度分为G组(<500 μm)、H组(500~540 μm)和I组(>540 μm)。统计不同角膜曲率、角膜瓣厚度、角膜厚度情况下3 种OBL产生的比例,并采用多元Logistic回归模型进行统计分析。结果:300 眼均发生OBL。以瓣外OBL作为参照,角膜瓣越薄,越容易出现瓣内快速OBL(r=-0.719,P=0.034)和瓣内慢速OBL(r=-0.875,P=0.044)。以瓣内慢速OBL作为参照,角膜曲率越高,越容易出现瓣内快速OBL(r=0.923,P=0.046);角膜瓣越厚,越容易出现瓣外OBL(r=0.897,P=0.044)。结论:OBL的产生与角膜曲率、角膜瓣厚度、角膜厚度均存在一定的相关性,但瓣外OBL、瓣内快速OBL和瓣内慢速OBL对Visumax飞秒激光辅助的LASIK术后视觉质量的影响及远期疗效仍有待进一步观察研究。  相似文献   
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