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91.
目的:比较生物膜与膨体聚四氟乙烯在动脉瘤包裹的远期治疗效果。方法:实验于2004-12/2006-10年在南方医院神经外科实验室与广东冠昊动物实验中心进行。取成年健康杂种犬10只,采用显微外科技术,将双侧的颈外静脉1.5cm嫁接双侧颈总动脉缺损1.5cm制作梭形动脉瘤模型20枚。左侧10枚应用生物膜(广东冠昊生物科技有限公司产品)包裹治疗,右侧10枚应用膨体聚四氟乙烯(美国戈尔公司周围血管补片)包裹治疗。术后第1,3,6,9,12个月行彩色多普勒超声血动态观察血流动力学变化,第12个月进行数字减影血管造影检测及解剖组织学观察。结果:10只犬全部进入结果分析。①血流动力学观察:生物膜包裹侧瘤腔消失、形态上趋于正常的颈总动脉,管腔均通畅,造影剂快速通过无滞留;血流恢复为层流,频谱特征与颈总动脉一致;1个月时生物膜与瘤壁存在微小间隙,3个月后间隙完全消失,12个月时血管顺应性、弹性与颈总动脉基本相匹配。膨体聚四氟乙烯包裹侧瘤腔消失、管腔通畅6枚,腔内为层流,频谱特征与颈总动脉相似,但速度明显高于远近端颈总动脉;瘤腔轻度缩窄,内壁出现轻度波状充盈缺损,包裹片长度轻度缩短;1个月和3个月各出现2枚血栓性闭塞,经主动脉弓照影不显像。6个月内膨体聚四氟乙烯与瘤壁存在清晰微小间隙,6个月后间隙消失。②组织学观察:生物膜包裹侧外表柔软类似颈总动脉,有较多毛细血管长入但维持原形,瘤腔内膜光滑无增厚,内皮细胞无增生、脱落,未见附壁血栓;生物膜与瘤壁融合、多层次降解,降解间隙内较多新生血管、组织长入,未见炎症细胞。膨体聚四氟乙烯外表僵硬、未见周围组织长入;内膜增厚、不光滑,内皮细胞核密集、部分脱落,薄层血栓附壁;4例见胶冻状长圆柱形杂色血栓。膨体聚四氟乙烯与瘤壁嵌入无降解,未看到明显的毛细血管长入;有极少的成纤维细胞伸入,散在的淋巴细胞浸润及少量巨噬细胞。结论:生物膜具有良好的理化性能与生物相容性,其效果优于膨体聚四氟乙烯,是动脉瘤包裹治疗的理想再生医学工程材料。  相似文献   
92.
Summary To obtain baseline standards of normal age-related development of the sphenoid sinus during childhood magnetic resonance images of the sphenoid sinus in 401 patients less than 15 years old were reviewed. T1-weighted sagittal and T2-weighted axial scans were evaluated for bone marrow conversion, development of pneumatization, spatial enlargement and septation of the sphenoid sinus. The sphenoid sinus had a uniformely low signal intensity (red bone marrow) on T1-weighted images in all children less than 4 months old. Signal intensity changes from hypo- to hyperintense (bone marrow conversion) started at age of 4 months. Onset of pneumatization was observed in 12% of the patients at age 13–15 months. By age 43–48 months, 85% of the patients showed pneumatization of the anterior part of the sphenoid bone. Pneumatization was complete in all patients older than 10 years. Enlargement of the sinus showed a characteristic profile in each dimension. Median septation was observed irregularly with age, with a maximum of 77%. Septum variants were noticed between 4.5% and 20%. The recognition of this phenomenon may serve as a reference for evaluating normal and abnormal development of the sphenoid sinus and may be of great value for diagnostic and therapeutic management of pathologic conditions of the child's sphenoid sinus and its surrounds.
Le sinus sphénoïdal pendant l'enfance : aspects en IRM du developpement normal
Résumé Afin de démontrer les aspects fondamentaux du développement du sinus sphénoïdal pendant l'enfance, nous avons revu l'aspect en IRM du sinus sphénoïdal de 401 patients agés de moins de 15 ans. L'étude de la moelle osseuse, le développement de la pneumatisation, la croissance et le cloisonnement du sinus sphénoïdal ont été explorés en séquences pondérées en T1 et en T2. Le sinus sphénoïdal se présente, en séquence pondérée en T1, avec un signal faible et uniforme (moelle osseuse rouge) chez tous les enfants agés de moins de 4 mois. Ce signal hypo-intense devient hyper-intense (transformation de la moelle osseuse) à partir du 4 ème mois. Le début de la pneumatisation est noté à 13–15 mois. A l'âge de 43–48 mois, la partie antérieure du sinus sphénoïdal est pneumatisée chez 85 % des enfants. La pneumatisation est complète chez tous les patients agés de plus de 10 ans. La croissance dans chaque direction de l'espace est caractéristique. L'apparition d'un septum médian est observée à une fréquence variable par tranche d'âge, avec un maximum de 77 %. Les variations existent dans 4,5 % à 20 % des cas. La connaissance de ce phénomène peut servir de référence pour évaluer le développement normal et anormal du sinus sphénoïdal et être d'un grand intérêt dans le diagnostic et le traitement des affections du sinus sphénoïdal et des régions voisines chez l'enfant.
  相似文献   
93.
The purpose of our study was to evaluate mammographic image quality of various methods of reconstructive breast surgery with specific reference to the possibility of diagnosis of recurrent tumors. A total of 39 patients who underwent breast reconstruction following modified radical mastectomy were subject to clinical and mammographic examination. Three groups were formed: (a)autonomous tissue reconstruction (TRAM flap; n = 9), (b) submuscular silicon gel prostheses (n = 21), and (c) supramuscular silicon gel prostheses (n = 9). Mammographic image quality of the groups was compared by two radiologists working together using a point system where five specific criteria were valued and scored. The result was tabulated into three quality levels: good, acceptable, and limited. Mammograms were assessed as good, acceptable, or limited, respectively, as follows: group I: 7(77.8%), 1(11.1%), (111.1%): group II. 4 (19%), 11 (52.4%), 6 (28.6%)l; group III: 3 (33.3%), 4 (44.5%), 2 (22.2%). The TRAM-flap method of reconstruction displays a high degree of mammographie image quality and therefore is preferable with respect to early diagnosis of recurrent tumors.  相似文献   
94.
Spermatic vein embolization with hot contrast material: fertility results   总被引:2,自引:0,他引:2  
Spermatic venography with hot contrast material embolization was undertaken in 81 patients with varicoceles and infertility. Long-term follow-up information was available in 91% of the patients, and there was an overall conception rate of 40.5%. Embolization with hot contrast material was easily performed without special embolization devices and proved to be a safe and effective technique.  相似文献   
95.
96.
97.
Electroconvulsive therapy (ECT) is the most effective treatment for severe depression but its neurocognitive mechanisms are unclear. This randomized, sham-controlled functional magnetic resonance imaging (fMRI) study explored the effects of a single ECT on neural response to affective pictures. Twenty-seven patients with major depressive disorder were randomized to a single active ECT (N?=?15) or sham (N?=?12) session in a double-blind, parallel-group design. On the following day, patients underwent fMRI during which they viewed pleasant, unpleasant and neutral pictures and performed a free recall test after the scan. Mood symptoms were assessed before ECT/sham and at the time of fMRI. Subsequently, all patients continued active ECT as usual. Mood symptoms were reassessed after six active ECT sessions. A single ECT vs. sham session reduced neural response to unpleasant vs. pleasant pictures in the medial prefrontal cortex, a region showing greater response in the more depressed patients. This effect occurred in the absence of between-group differences in picture recall, mood symptoms or concomitant medication. In conclusion, modulation of medial prefrontal hyper-activity during encoding of negative affective information may be a common mechanism of distinct biological depression treatments.  相似文献   
98.
Four patients with hepatocellular carcinoma, shunting of blood from the hepatic artery to the portal vein, and hyperkinetic portal hypertension were treated by transcatheter embolization of the hepatic artery. In three acutely bleeding patients variceal hemorrhage was controlled by the embolization. Following embolization hepatofugal portal venous flow became hepatopetal in all four patients. No serious complications were encountered. When hepatoma is complicated by arterioportal shunting and hyperkinetic portal hypertension, occlusion of the fistula by transcatheter embolotherapy can reduce the portal pressure.  相似文献   
99.
Creek  MR; Mani  C; Vogel  JS; Turteltaub  KW 《Carcinogenesis》1997,18(12):2421-2427
The tissue distribution and macromolecular binding of benzene was studied over a dose range spanning nine-orders of magnitude to determine the nature of the dose-response and to establish benzene's internal dosimetry at doses encompassing human environmental exposures. [14C]-Benzene was administered to B6C3F1 male mice at doses ranging between 700 pg/kg and 500 mg/kg body wt. Tissues, DNA and protein were analyzed for [14C]-benzene content between 0 and 48 h post-exposure (625 Ng/kg and 5 microg/kg dose) by accelerator mass spectrometry (AMS). [14C]-Benzene levels were highest in the liver and peaked within 0.5 h of exposure. Liver DNA adduct levels peaked at 0.5 h, in contrast to bone marrow DNA adduct levels, which peaked at 12-24 h. Dose- response assessments at 1 h showed that adducts and tissue available doses increased linearly with administered dose up to doses of 16 mg/kg body wt. Tissue available doses and liver protein adducts plateau above the 16 mg/kg dose. Furthermore, a larger percentage of the available dose in bone marrow bound to DNA relative to liver. Protein adduct levels were 9- to 43-fold greater than DNA adduct levels. These data show that benzene is bioavailable at human-relevant doses and that DNA and protein adduct formation is linear with dose over a dose range spanning eight orders of magnitude. Finally, these data show that the dose of bioactive metabolites is greater to the bone marrow than the liver and suggests that protein adducts may contribute to benzene's hematoxicity.   相似文献   
100.
Neurofibromatosis type 1 (NF1, OMIM 162200), caused by NF1 gene mutations, exhibits multi‐system abnormalities, including skeletal deformities in humans. Osteocytes play critical roles in controlling bone modeling and remodeling. However, the role of neurofibromin, the protein product of the NF1 gene, in osteocytes is largely unknown. This study investigated the role of neurofibromin in osteocytes by disrupting Nf1 under the Dmp1‐promoter. The conditional knockout (Nf1 cKO) mice displayed serum profile of a metabolic bone disorder with an osteomalacia‐like bone phenotype. Serum FGF23 levels were 4 times increased in cKO mice compared with age‐matched controls. In addition, calcium‐phosphorus metabolism was significantly altered (calcium reduced; phosphorus reduced; parathyroid hormone [PTH] increased; 1,25(OH)2D decreased). Bone histomorphometry showed dramatically increased osteoid parameters, including osteoid volume, surface, and thickness. Dynamic bone histomorphometry revealed reduced bone formation rate and mineral apposition rate in the cKO mice. TRAP staining showed a reduced osteoclast number. Micro‐CT demonstrated thinner and porous cortical bones in the cKO mice, in which osteocyte dendrites were disorganized as assessed by electron microscopy. Interestingly, the cKO mice exhibited spontaneous fractures in long bones, as found in NF1 patients. Mechanical testing of femora revealed significantly reduced maximum force and stiffness. Immunohistochemistry showed significantly increased FGF23 protein in the cKO bones. Moreover, primary osteocytes from cKO femora showed about eightfold increase in FGF23 mRNA levels compared with control cells. The upregulation of FGF23 was specifically and significantly inhibited by PI3K inhibitor Ly294002, indicating upregulation of FGF23 through PI3K in Nf1‐deficient osteocytes. Taken together, these results indicate that Nf1 deficiency in osteocytes dramatically increases FGF23 production and causes a mineralization defect (ie, hyperosteoidosis) via the alteration of calcium‐phosphorus metabolism. This study demonstrates critical roles of neurofibromin in osteocytes for osteoid mineralization. © 2017 American Society for Bone and Mineral Research.  相似文献   
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