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81.
Safety of injectable autologous human fibroblasts 总被引:3,自引:0,他引:3
Keller G Sebastian J Lacombe U Toft K Lask G Revazova E 《Bulletin of experimental biology and medicine》2000,130(8):786-789
Autologous dermal fibroblasts after propagation in cell culture were used for face soft tissue augmentation. Twenty patients
aged 37–61 years with facial rhytides and atrophic scars were treated with autologous fibroblasts from cell culture. Significant
sustained clinical improvement was observed. Cells of early passages (4, 5, 6) were used for injection. The study showed that
cultured fibroblasts were functionally active and produced large quantities of type I collagen.In vitro studies of scar formation potency of injectable fibroblasts showed that these cells possessed normal collagen gel contraction
capacity.In vivo experiments showed that cultured fibroblasts exhibited no oncogenic properties and induced no tumors in nude mice.
Translated fromByulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 130, No. 8, pp. 203–206, August, 2000 相似文献
82.
Summary We describe a case of a vascular mass arising secondary to a postoperative vertebral arteriovenous fistula mimicking recurrent cervical neurofibroma on CT in a patient with neurofibromatosis. Angiography was required for diagnosis. The recurrent tumor resolved following balloon embolization of the fistula. 相似文献
83.
目的探讨在CT引导下经皮经椎弓根行脊椎肿瘤穿刺活检的价值。方法CT引导下选择最佳穿刺点、穿刺角度及深度并随时调整,以确保整个穿刺过程在病变的椎弓根内及椎体内完成。结果所有病例均未发生穿刺并发症。11例所取组织量可满足病理检查要求。1例取材量不足而未能得出满意诊断结果。结论CT引导下经椎弓根行脊椎肿瘤穿刺活检取材准确,操作安全可靠。 相似文献
84.
85.
血管内超声(IVUS)图像是观测血管内部结构的首选影像学手段,基于IVUS图像的内膜和中外膜边界的提取是实现冠脉粥样硬化精准诊断的前提和关键。针对IVUS图像结构复杂、对比度低、边界提取困难等问题,本研究提出一种基于改进TransUnet网络的分割方法。首先,针对IVUS图像边界提取难点,对边血管、血管分叉、导丝伪像、阴影等4种图像结构进行建模,并基于建模结果予以定向数据增强;而后,结合IVUS图像的环状结构分布特点,在TransUnet网络中提出了Polar-bias归纳偏置的策略,并对IVUS图像进行像素级的分类;最后,基于分类结果优化GVF snake模型的外力场,进而提取IVUS图像的内膜和中外膜边界。采用国际标准IVUS图像数据集(两组不同中心频率,共512幅图像)对算法进行评测,引入JMard距离(JM),Hausdorff距离(HD)和面积差异百分比(PAD)等3个评测指标,在数据集A中JM为0.87, HD为0.87, PAD为0.18,数据集B中JM为0.91, HD为0.25, PAD为0.08。实验结果表明,所提出的算法在两组数据集的内膜及中外膜提取问题中的表现均... 相似文献
86.
R. Büttemeyer R. Hohlc W. Meyer-Gattermann J. C. Bruck 《European journal of plastic surgery》1994,17(1):23-27
Summary Three cases of homologous and one of autologous free fat block transplantation for breast augmentation were seen 10 to 20 years after operation due to late complications. Displacement of heavy tumors, local mastitis or disrupted capsules following local trauma led to admission. The calcified centrally necrotic cysts were treated by subcutaneous mastectomy or local enucleation and immediate reconstruction by subpectoral augmentation with silicone-gel implants or reduction mammoplasty. 相似文献
87.
Jörg Wilting Cecilia Ebensperger Thomas S. Müller Haruhiko Koseki Johan Wallin Bodo Christ 《Anatomy and embryology》1995,192(3):221-227
The Pax-1 gene has been found to play an important role in the development of the vertebral column. The cervico-occipital transitional zone is a specialized region of the vertebral column, and malformations of this region have frequently been described in humans. The exact embryonic border between head and trunk is a matter of controversy. In order to determine a possible role of Pax-1 in the development of the cervico-occipital transitional zone we studied the expression of this gene in a series of quail embryos and murine fetuses with in situ hybridization and immunohistochemistry. Pax-1 is expressed in all somites of the embryo, including the first five occipital ones. During embryonic days 3–5 the gene is down-regulated in the caudal direction within the first five somites, whereas more caudally Pax-1 is strongly expressed in the cells of the perinotochordal tube. In 5-day-old quail embryos, the cartilaginous anlage of the basioccipital bone has developed and there is no more expression of Pax-1 in this region. The fusion of the dens axis with the body of the axis also coincides with switching off of the Pax-1 gene. More caudally, the gene is continuously expressed in the intervertebral discs of murine embryos and therefore seems to be important for the process of resegmentation. Quail embryos do not possess permanent intervertebral discs. Hyper- or hyposegmentation defects may be explained by an over- or under-expression of Pax-1 during development. We also reinvestigated the border between the head and trunk in chick embryos by performing homotopical grafting experiments of the 5th somite between chick and quail embryos. Grafted quail cells formed mainly the caudal end of the basioccipital bone. They were also located in the cranial half of the ventral atlantic arch, and only a few cells were found in the tip of the dens axis. 相似文献
88.
Quantitative ultrasound (QUS) is emerging as a simple, inexpensive and noninvasive method for assessing bone quality and
assessing fracture risk. We assessed the usefulness of a contact calcaneal ultrasonometer by studying normal premenopausal
women (group I, n= 53), normal postmenopausal women (group II, n= 198), and osteoporotic women without (group III, n= 141) and with vertebral fractures (group IV, n= 53). The osteoporotic subjects had a T-score of the spine or hip neck bone mineral density (BMD) <−2.5 based on the local Chinese peak young mean values. When compared
with postmenopausal controls, mean broadband ultrasound attenuation (BUA), speed of sound (SOS), and quantitative ultrasound
index (QUI) were 26%, 2.1% and 25% lower in women with vertebral fractures (p all <0.005). The correlation coefficients between QUS parameters and BMD of the spine and hip ranged between 0.4 and 0.5.
The ability of the QUS to discriminate between patients groups was determined based on the mean value of normal premenopausal
women in group I. The mean T-score for women with fractures was −2.87 ± 1.02 for BUA, −2.54 ± 0.79 for SOS, −3.17 ± 0.70 for QUI, −2.65 ± 0.86 for L2–4
BMD and −2.53 ± 0.66 for hip neck BMD. After adjustment for age and body mass index, the odds ratio of vertebral fracture
was 1.71 (95% CI 1.2–2.6) for each 1 SD reduction in BUA, 2.72 (1.3–5.3) for SOS, 2.58 (1.4–4.6) for QUI, 2.33 (1.6–3.3) for
L2–4 BMD, 2.09 (1.37–3.20) for femoral neck BMD and 1.88 (1.34–2.92) for total hip BMD. The association between the QUS parameters
and vertebral fracture risk persisted even adjustment for BMD. The area under the receiver operating characteristic curve
for BUA for vertebral fracture was 0.92, for SOS, QUI, L2–4 BMD and femoral neck BMD was 0.95, and for total hip was 0.91.
Received: 7 January 1999 / Accepted: 18 May 1999 相似文献
89.
In a follow-up study 27 patients were evaluated after anterior cruciate ligament (ACL-)reconstruction combined with high tibial osteotomy because of chronic rupture of the ACL, cartilaginous lesions of the medial compartment and varus malalignment. They were divided into two groups. In 14 patients (non-LAD group) ACL reconstruction was performed using the central third of the autologous patellar tendon modified according to Eriksson-Trillat. Thirteen patients (LAD group) underwent repair with the same technique, but a Kennedy ligament augmentation device (LAD) in hot dog technique and fixed over the top was added. The postoperative treatment was the same in both groups. All patients were examined according to IKDC criteria. KT-1000 arthrometer testing at maximum manual traction was performed. Although the mean follow-up interval was more than double in the non-LAD group (non-LAD: 127 months vs LAD: 58 months), the subjective and clinical results, IKDC evaluation and KT-1000 arthrometer testing results were similar, showing no statistically significant difference. Further, no complications due to the use of LAD occurred. In this study no evident functional or clinical advantage from the augmentation performed could be shown.Investigation performed at the Department of Orthopaedic and Trauma Surgery, University Hospital Basle, Switzerland. No benefits in any form have been received or will be received from a commercial party related directly or indirectly to the subject of this article. Funds were received in total or partial support of the research or clinical study presented in this article. The funding sources were SUVA Assurance, Lucerne, and the science fund of the University Hospital Basle 相似文献
90.
S. N. Cenk Büyükünal 《Pediatric surgery international》1993,8(3):277-280
The aim of this study was to present the results of a new bladder closure and augmentation technique in children born with bladder exstrophy where primary surgical closure was impossible. The technique was performed in four children with small, noncompliant, inelastic bladders in which secondary changes such as squamous epithelial metaplasia and polypoid transformation had developed. During the opration, a full-thickness rectus abdominis muscle island flap with an intact neurovascular pedicle was prepared from the left abdominal quadrant and rotated to cover the bladder defect and aid in augmentation. The inner layer formed by peritoneum was sutured to the edges of the bladder defect. Postoperative endoscopic and histopathologic investigations revealed the inner, peritoneal layer of the flap to be completely covered by transitional urinary bladder epithelium. Considering the advantages of the technique from this limited experience, the evidence suggests that there is no need for a major gastrointestinal operation for bladder augmentation. A reasonable bladder capacity was available, there was no mucus production from the inner layer of the flap, and metabolic and electrolyte disturbances were reduced. 相似文献