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511.
目的:探讨在大鼠脑缺血的情况下经尾静脉注射移植骨髓基质细胞的可行性,为骨髓基质细胞脑移植治疗提供一种简捷、安全、有效的途径。方法:实验于2005-10/2006-08在北华大学医学院实验中心完成。取1~2个月龄SD大鼠双侧股骨和胫骨,体外分离培养大鼠骨髓基质细胞。取体质量为280~320g的SD大鼠25只,采用颈内动脉线栓法制作大脑中动脉梗死模型,造模成功后在25只大鼠中随机盲抓分为2组:骨髓基质细胞移植组(n=15)、对照组(n=10)。骨髓基质细胞移植组经静脉缓慢推入含Hoeschst33342标记的骨髓基质细胞细胞悬液1mL(2.0×107个细胞),对照组用同样方法经尾静脉注入等量不含骨髓基质细胞的DMEM培养液作为对照。分别于移植后1d、7d、14d时间点对两组大鼠进行神经功能损害严重程度评分及大脑组织切片观察比较。结果:25只大鼠均进入结果分析。①各代细胞90%以上表达巢蛋白阳性。②与对照组相比,骨髓基质细胞移植组大鼠运动、神经功能恢复明显[骨髓基质细胞移植组:(6.10±2.96),(3.30±1.83),(2.10±1.20)分;对照组:(7.43±1.51),(6.14±1.35),(4.43±1.40)分,P<0.05]。③骨髓基质细胞移植组大鼠脑组织结构较清晰、完整;对照组大鼠脑组织破坏溶解,组织结构松散,细胞结构不完整,胞浆疏松,染色变浅,间质水肿。结论:通过静脉注射进行骨髓基质细胞移植,方法简便、安全,对神经损伤动物组织重建及神经功能有确切的修复效果。 相似文献
512.
Background: Dentinal hypersensitivity has been defined as a short, sharp pain arising from exposed dentine as a result of various stimuli such as heat, cold, chemical, or osmotic, that cannot be ascribed to any other pathology. This study was conducted to assess the efficacy of three commercially available toothpastes in the reduction of dentinal hypersensitivity. Methods: A total of 149 subjects (72 males and 77 females; aged 20 to 60 years) were entered into the study and randomly divided into four groups: Group 1 – toothpaste containing 5% potassium nitrate; Group 2 – toothpaste containing 5% calcium sodium phosphosilicate with fused silica; Group 3 – toothpaste containing 3.85% amine fluoride; and Group 4 – a placebo toothpaste. After sensitivity scores for controlled air stimulus and cold water at baseline were recorded, subjects were given toothpastes and sensitivity scores were measured again at 2 weeks and 6 weeks. Results: All groups showed a reduction in sensitivity scores at 2 weeks and 6 weeks. The calcium sodium phosphosilicate group was found to be significantly better compared to the other groups at the end of 6 weeks. Conclusions: The calcium sodium phosphosilicate group showed a better reduction in the symptoms of dentinal hypersensitivity. 相似文献
513.
Dahl GV; Rivera G; Pui CH; Mirro J Jr; Ochs J; Kalwinsky DK; Abromowitch M; Look AT; Murphy SB 《Blood》1985,66(5):1110-1114
We treated 24 children and adolescents with stage III or IV lymphoblastic non-Hodgkin's lymphoma, using a protocol designed for patients with poor-prognosis acute lymphoblastic leukemia (ALL). Early therapy consisted of teniposide plus cytarabine administered before and immediately after prednisone, vincristine, and asparaginase. The two- drug combination was also given intermittently with continuous 6- mercaptopurine and methotrexate during the first year of continuation chemotherapy. Periodic intrathecal methotrexate and delayed cranial irradiation were used to prevent central nervous system involvement. Anthracycline compounds, alkylating agents, high-dose methotrexate, and involved-field irradiation were not used in any phase of treatment. Twenty-two (96%) of the 23 evaluable patients achieved complete remission. With a median follow-up of 2 1/2 years, only four patients have relapsed; the remainder have been disease-free for eight months to more than five years. The projected four-year continuous complete remission rate is 73% for all patients and 79% for the 19 with mediastinal involvement at diagnosis. These results demonstrate that use of teniposide plus cytarabine with an otherwise conventional plan of ALL therapy is an effective approach to the treatment of childhood lymphoblastic lymphoma. 相似文献
514.
515.
A total of 3 out of 5 cases of major congenital ear malformation seen in out patient department in two years in 1997 and 1998 were operated for functional reconstruction of external auditory canal, middle ear and ossicular chain. 2 cases of bilateral malformation of auricle grade 2 were advised otoplastic repair prior to tympanoplasty. Out of the 3 cases operated by anterior transatretic bone approach, 2 cases had good hearing improvement in air conduction threshold of up to 30 db hearing level (averages of 0.5,1.2 and 3 khz). One case developed external canal stenosis by six months post operatively and drop in hearing. There was no facial nerve injury in any of the cases. This paper analyses the importance of facial nerve delineation preoperatively based on its embryological development and its relationship with temporal bone and membranous labyrinth. It also focuses on the various parameters like timing of surgery, importance of (CT) scanning, use of facial nerve monitor and surgical expertise and experience which govern the surgical intervention and its results in congenital ear atresia.KEY WORDS: Congenital ear atresia, Facial nerve, Transatretic bone approach 相似文献
516.
Background
Erectile Dysfunction (ED) is one of the major social problems causing significant distress in men. Despite the increasing difficulty in management, knowledge, and understanding of factors responsible for its development are important for prevention and care.Objectives
To assess the prevalence and risk factors for ED among men in Niger Delta Region of Nigeria, in order to determine its contextual variables.Methods
Subjects included 400 male patients attending the general outpatients'' clinic (GOPC) of the University of Uyo Teaching Hospital. Respondents completed the abridged version of the International Index of Erectile Function (IIEF-5).Results
A total of 166 (41.5%) subjects had ED; 66 (16.5%) had mild; 32 (8.0%) mild to moderate; 24 (6.0%) moderate; while 45 (11.3%) had severe 37 (9.2%) resulted from hypertension and its medications; 29 (7.3%) from diabetes; 49 (12.2%) from a combination of both and their therapies (P=0.044); 24 (6.0%) had history of previous surgery; while for 27 (6.8%) it was from undiagnosed medical conditions (p=0.001). The ED increases with age and is more among married and educated men.Conclusion
ED is a common problem among men in Niger Delta region. Therefore, efforts must be made to reduce the incidence by dealing with the factors responsible for its development. 相似文献517.
BR Hansen SB Haugaard FK Jensen JEB Jensen L Andresen J Iversen O Andersen 《HIV medicine》2010,11(4):266-275
Objectives
The aim of the study was to investigate the effect of long‐term high‐physiological‐dose recombinant human growth hormone (rhGH) therapy on fat distribution and glucose metabolism in HIV‐infected patients.Methods
Forty‐six HIV‐infected Caucasian men on highly active antiretroviral therapy (HAART), with an age range of 21–60 years and no significant comorbidity, were included in this randomized, placebo‐controlled, double‐blind, single‐centre trial. Twenty‐eight subjects were randomized to 0.7 mg/day rhGH, and 18 subjects to placebo, administered as daily subcutaneous injections between 1 and 3 pm for 40 weeks. Endpoints included changes in visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), limb fat mass, percentage of limb fat, plasma lipids, insulin resistance and glucose tolerance.Results
VAT and trunk fat mass decreased significantly in the GH group compared with the placebo group [−19 cm2 (−11%) vs. 12 cm2 (6%), P=0.03, and −548 g (−9%) vs. 353 g (6%), P<0.01, respectively]. The beneficial fat redistribution in the GH group occurred without concomitant changes in subcutaneous fat at the abdomen or extremities. rhGH therapy was well tolerated. Insulin resistance, glucose tolerance, and total plasma cholesterol and triglycerides did not significantly change during intervention.Conclusions
Daily 0.7 mg rhGH treatment for 40 weeks reduced abdominal visceral fat and trunk fat mass in HIV‐infected patients. This treatment appeared to be safe with respect to glucose tolerance and insulin sensitivity.518.
519.
520.
JA Povlsen B Løfgren LE Rasmussen JM Nielsen R Nørregaard SB Kristiansen HE Bøtker TT Nielsen 《Clinical and experimental pharmacology & physiology》2009,36(9):892-898
- 1 Because diabetic hearts have an increased threshold for cardioprotection by ischaemic preconditioning (IPC), we hypothesized that protection by l ‐glutamate during reperfusion is restricted in Type 2 diabetic hearts. Previously, we found that l ‐glutamate‐mediated postischaemic cardioprotection mimics IPC.
- 2 Rat hearts were studied in a Langendorff preparation perfused with Krebs’–Henseleit solution and subjected to 40 min global no‐flow ischaemia, followed by 120 min reperfusion. l ‐Glutamate (0, 15 and 30 mmol/L) was added to the perfusate during reperfusion of hearts from non‐diabetic (Wistar‐Kyoto) and diabetic (Zucker diabetic fatty (ZDF)) rats, studied at 16 weeks of age. The infarct size (IS)/area‐at‐risk (AAR) ratio was the primary end‐point. Expression of l ‐glutamate excitatory amino acid transporter (EAAT) 1 (mitochondrial) and EAAT3 (sarcolemmal) was determined by quantitative polymerase chain reaction and immunoblotting.
- 3 The ISS/AAR ratio did not differ between control hearts from Wistar‐Kyoto and ZDF rats (0.52 ± 0.03 and 0.51 ± 0.04, respectively; P = 0.90). l ‐Glutamate (15 mmol/L) significantly reduced the IS/AAR ratio in non‐diabetic hearts, but not in diabetic hearts, compared with their respective controls. The higher concentration of l ‐glutamate (30 mmol/L) reduced infarct size in diabetic hearts to the same degree as in non‐diabetic hearts (IS/AAR 0.35 ± 0.03 (P = 0.002) and 0.34 ± 0.03 (P = 0.004), respectively). The mitochondrial l ‐glutamate transporter EAAT1 was downregulated in hearts from ZDF rats at both the mRNA and protein levels (P < 0.0005 and P < 0.0001, respectively). However, there was no change in EAAT3 expression at the protein level. Myocardial l ‐glutamate content was increased by 43% in diabetic hearts (P < 0.0001).
- 4 Hearts from obese diabetic rats have an elevated threshold for metabolic postischaemic cardioprotection by l ‐glutamate. These findings may reflect underlying mechanisms of inherent resistance against additional cardioprotection in the diabetic heart.