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61.
The administration of growth factors (GFs) for treatment of experimental spinal cord injury (SCI) has shown limited benefits. One reason may be the mode of delivery to the injury site. We have developed a minimally invasive and safe drug delivery system (DDS) consisting of a highly concentrated collagen solution that can be injected intrathecally at the site of injury providing localized delivery of GFs. Using the injectable DDS, epidermal growth factor (EGF) and basic fibroblast growth factor (FGF-2) were co-delivered in the subarachnoid space of Sprague-Dawley rats. The in vivo distribution of EGF and FGF-2 in both injured and uninjured animals was monitored by immunohistochemistry. Although significant differences in the distribution of EGF and FGF-2 in the spinal cord were evident, localized delivery of the GFs resulted in significantly less cavitation at the lesion epicenter and for at least 720 mum caudal to it compared to control animals without the DDS. There was also significantly more white matter sparing at the lesion epicenter in animals receiving the GFs compared to control animals. Moreover, at 14 days post-injection, delivery of the GFs resulted in significantly greater ependymal cell proliferation in the central canal immediately rostral and caudal to the lesion edge compared to controls. These results demonstrate that the injectable DDS provides a new paradigm for localized delivery of bioactive therapeutic agents to the injured spinal cord.  相似文献   
62.
BACKGROUND: Although several myocardial iodine 123 metaiodobenzylguanidine (MIBG) indices are increasingly used to detect alterations in myocardial sympathetic activity in various forms of cardiac pathology, published measurements of normal values and within-subject variability are lacking. METHODS AND RESULTS: Twenty-five healthy volunteers underwent planar and single photon emission computed tomography (SPECT) imaging. Heart-mediastinum ratio (H/M) and myocardial washout were calculated from planar images comparing three different methods for the assessment of myocardial activity: (1) global region over the myocardium (cavity included), (2) global region over the myocardium (cavity excluded), and (3) fixed small myocardial region. Segmental (relative) uptake and washout were assessed by SPECT. For all MIBG indices, the interindividual variation was the lowest for methods 1 and 2. In SPECT this variation was low for relative segmental uptake compared with washout. In 9 subjects a second MIBG scintigraphy was performed after 3 months. The within-subject variability of H/M and washout assessed by planar methods 1 and 2 was 5%, whereas it was approximately 9% for planar method 3. For relative segmental uptake from SPECT, this variability was 5%. CONCLUSION: MIBG H/M (planar) and relative segmental uptake (SPECT) show a low interindividual and within-subject variability. This enables the detection of small (regional) variations in myocardial sympathetic nervous function, especially to monitor the effect of therapeutic interventions in patients with various cardiac diseases.  相似文献   
63.
Vestibular schwannomas have been traditionally managed with microsurgical removal and in recent years, stereotactic radiotherapy. However, there is a group of patients in whom a conservative management approach might represent a desirable alternative. The aim of this study was to determine the natural history and outcome following the conservative management of 72 patients with unilateral vestibular schwannomas. This is a prospective cohort review of a previously published group of patients [Clin. Otolaryngol. (2000) 25, 28-39] with unilateral vestibular schwannoma that were initially analysed at our institution in 1998 [Walsh R.M., Bath A.P., Bance M.L. et al., Clin. Otolaryngol. (2000) 25, 28]. The mean duration of follow-up was 80 months (range 52-242 months). All the patients in the study underwent serial magnetic resonance imaging (MRI) for assessment of tumour growth. Patients were deemed to have failed conservative management if there was evidence of rapid radiological tumour growth and/or increasing signs and symptoms, which necessitated active intervention. The mean tumour growth rate for the entire group at the second review was 1 mm/year (range -0.84-9.65 mm/year). The mean growth rate for cerebellopontine angle tumours (1.3 mm/year) was significantly greater than that of internal auditory canal (IAC) tumours (0 mm/year) (P = 0.005). The majority of tumours (87.14%) grew <2 mm/year. There was significant tumour growth seen in 38.9%, no or insignificant growth in 41.7%, and negative growth in 19.4%. Twenty-three patients (32%) failed conservative management at the second review. There was no difference in the outcome of these failed patients in comparison with patients who underwent primary treatment without a period of conservative management. The mean growth rate of tumours in patients that failed conservative management (3.1 mm/year) was significantly greater than that in patients who did not fail (0.2 mm/year) (P < 0.001). No factors predictive of tumour growth or failure of conservative management were identified. Hearing deterioration with pure tone averages (0.5, 1, 2, 3 kHz) and speech discrimination scores occurred irrespective of tumour growth. This prospective study further emphasizes the role of conservative management in selected cases of vestibular schwannomas. Tumours in this study confined to the IAC typically demonstrated minimal or no growth on serial MRI scanning. Regular follow-up with interval scanning is mandatory in all patients.  相似文献   
64.
4分子治疗分析肿瘤细胞中的分子遗传性变异及后天变异的方法正在快速成熟起来。这些方法通常涉及基因组学、转录特征性识别及蛋白质组学,有利于更深入地了解ALL的发病机理,使用于临床评估的靶向治疗全面发展。最终,这些层出不穷的新技术将营造出一个全新的个性化分子医学时代,创造出效果更好而毒性更低的治疗方案。尽管治疗方案均显示了药物介入控制细胞周期进程、基因转录、细胞运动、凋亡及细胞代谢信号通路的可行性(图1),但针对ALL的分子治疗情况(表1)仍差强人意。我们将从众多正处于临床前期或早期临床研究的分子治疗方案中,选择出那…  相似文献   
65.
利用目前的治疗手段,80%的急性淋巴细胞白血病(acute lymphoblastic leukem ia,ALL)患儿均能得到治愈,尚有部分患者需接受强化治疗,但治疗的副作用也带来了急性或远期的严重并发症。此外,成人ALL病人的生存率依然低于40%。因此,本病需要既可以提高治愈率又能改善生活质量的新治疗方案。本文讨论了新出现的可能会改善ALL病人预后的治疗方法,包括现有常规化疗药物的新剂型、新的抗代谢药和核苷衍生物、白血病相关抗原的单克隆抗体,针对白血病细胞的基因异常及相关信号通路的分子治疗。1常规化疗药物的新剂型化疗药物的脂质体剂型是将药物…  相似文献   
66.
Abstract. Matsaniotis, N., Tzortzatou-Stathopoulou, F., Thomaidis, Th., Karakatsani-Kerasioti, Z., Theodoridis, Ch. and Dacou-Voutetakis, C. (First Department of Paediatrics of Athens University, "Aghia Sophia" Children's Hospital, Athens, Greece). Diabetes mellitus and Addison's disease in an adolescent female. Acta Paediatr Scand, 70: 949, 1981.-This short report describes a 16-year-old female who presented with Addison's disease 6 years after diabetes mellitus had been diagnosed. The possibility of both conditions being present should be borne in mind whenever an unexplained reduction of insulin requirements is noted, especially if this is accompanied by cutaneous pigmentation. The metabolic interrelationships of the two conditions are briefly discussed.  相似文献   
67.
Immunoglobulins were estimated in the cerebrospinal fluid from 70 cases of nervous system diseases. Thirty childern with evidence of C.N.S. irritation without infection served as controls. The immunoglobulins were higher in cases with C.N. S infections. Within this group meningeal involvement (tubercular and pyogenic) resulted in a significant rise in IgG compared to viral encephalitis. The proportion of immunoglobulin in the CSF protein can be helpful in distinguishing TBM from PM.  相似文献   
68.

Background  

Stress urinary incontinence is a common condition affecting approximately 20% of adult women causing substantial individual (quality of life) and economic (119 million Euro/year spent on incontinence pads in the Netherlands) burden. Pelvic floor muscle training (PFMT) is regarded as first line treatment, but only 15-25% of women will be completely cured. Approximately 65% will report that their condition improved, but long term adherence to treatment is problematic. In addition, at longer term (2-15 years) follow-up 30-50% of patients will end up having surgery. From 1996 a minimal invasive surgical procedure, the Tension-free Vaginal Tape (TVT) has rapidly become the gold standard in surgical treatment of stress urinary incontinence. With TVT 65-95% of women are cured. However, approximately 3-6% of women will develop symptoms of an overactive bladder, resulting in reduced quality of life. Because of its efficacy the TVT appears to be preferable over PFMT but both treatments and their costs have not been compared head-to-head in a randomised clinical trial.  相似文献   
69.
Two hundred twenty-eight patients with acoustic neuromas were seen between 1974 and 1985. Twenty-eight received no surgical treatment. Five patients who had undergone previous partial excision were excluded. The mean age was 71 years. The mean expected survival was 14.3 years. The mean follow-up interval was 51 months (range 12 to 120 months). All patients underwent at least two CAT scans (mean = 4). Tumor size ranged from 4 mm to 30 mm. Three patients underwent insertion of ventricular-peritoneal shunt for hydrocephalus (mean 16 months after presentation) and two patients partial tumor removal (mean 30 months after presentation). Tumor growth was measured in each patient using CAT scanning. Monitoring by clinical examination and regular CAT scanning is possible, but in this study 20% of patients required surgical treatment within one third of their expected survival time. This suggests that an expectant attitude for this group of patients may be a debatable form of management.  相似文献   
70.
To test the ability of Gianturco expandable metallic stents to dilate and maintain patency in stenotic venae cavae, stenosis of the inferior vena cava was created in seven mongrel dogs by the percutaneous injection of absolute ethanol into the paravascular retroperitoneal space. Gianturco stents, placed across the stenotic segment, resulted in successful dilatation with improved hemodynamics in four dogs. The stents failed to dilate an occluded vena cava in one dog; in the remaining dogs, stent placement was complicated by early migration and occlusion. Gianturco stents were placed in two patients, one with superior vena cava syndrome and one with retroperitoneal fibrosis that obstructed the inferior vena cava, and resulted in immediate relief of presenting symptoms. These results should be viewed cautiously, but further investigation into the clinical use of the stents is indicated, especially for patients for whom other treatments are difficult.  相似文献   
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