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131.
Jeffrey V. Rosenfeld MS FRACS FRCS 《Journal of clinical neuroscience》1994,1(4):231-242
Great advances in neurobiology have resulted from 100 years of neural transplantation research. In the last 20 years, there has been a focus on using neural transplantation to repair the damaged central nervous system (CNS) utilising experimental animal models of various human neurodegenerative disease and CNS injury. Since 1985, there has been a rapid proliferation of adrenal medullary autograft transplantation to the caudate nucleus of humans with Parkinson's disease. However, this operation proved to be unsuccessful and was associated with unacceptable morbidity. Implantation of human fetal mesencephalon into patients with severe parkinsonism has supplanted the adrenal operation and has produced promising results, with some patients reported to improve markedly and some evidence of graft survival noted on positron emission tomography (PET). Host tissue recovery appears to be an important mechanism for this clinical improvement. The optimal technique is to use three to four fetuses from induced abortions of 6.5 to 8 weeks gestation, with multiple stereotactic implants into the putamen and caudate nucleus. Many biological questions still remain and the community remains troubled by the ethical problems of using fetal tissue obtained from abortions. This procedure is still experimental and should be restricted to a few centres with excellence in cell and molecular biology. A multicentre study is needed to more carefully evaluate CNS transplantation. Cloned neural precursor cells or immortalized embryonic cell lines genetically modified to manufacture selected growth factors or neurotransmitters may offer an alternative to the use of human fetal tissue. Much more experimental animal research is necessary before transplantation can be used to treat other CNS maladies. 相似文献
132.
Simon Vinitski Carlos Gonzalez Feroze Mohamed Tad Iwanaga Robert L. Knobler Kamil Khalili John Mack 《Magnetic resonance in medicine》1997,37(3):457-469
Our aim was to develop an accurate multispectral tissue segmentation method based on 3D feature maps. We utilized proton density (PD), T2-weighted fast spin-echo (FSE), and T1-weighted spin-echo images as inputs for segmentation. Phantom constructs, cadaver brains, an animal brain tumor model and both normal human brains and those from patients with either multiple sclerosis (MS) or primary brain tumors were analyzed with this technique. Initially, misregistration, RF inhomogeneity and image noise problems were addressed. Next, a qualified observer identified samples representing the tissues of interest. Finally, k-nearest neighbor algorithm (k-NN) was utilized to create a stack of color-coded segmented images. The inclusion of T1 based images, as a third input, produced significant improvement in the delineation of tissues. In MS, our 3D technique was found to be far superior to that based on any combination of 2D feature maps (P < 0.001). We identified at least two distinctly different classes of lesions within the same MS plaque, representing different stages of the disease process. Further, we obtained the regional distribution of MS lesion burden and followed its changes over time. Neuropsychological aberrations were the clinical counterpart of the structural changes detected in segmentation. We could also delineate the margins of benign brain tumors. In malignant tumors, up to four abnormal tissues were identified: 1) a solid tumor core, 2) a cystic component, 3) edema in the white matter, and 4) areas of necrosis and hemorrhage. Subsequent neurosurgical exploration confirmed the distribution of tissues as predicted by this analysis. 相似文献
133.
观察了小鼠暴露在不同海拔梯度下脑含水量改变及其与脑水肿的关系。实验结果表明,小鼠由低海拔区快速进入高海拔区后脑组织的湿干比值和含水量均有增高(P<001),以进入高海拔区后的第7d为最高峰。组织学观察表明,此时脑神经细胞肿胀,胞浆内有空泡变性,胶质细胞和微血管周围有明显空晕。以上结果揭示,由低海拔区快速进入高海拔区后可致脑水肿形成。 相似文献
134.
目的 :观察氯沙坦对行维持性血透治疗的慢性肾功能衰竭 (CRF)患者心血管保护作用。方法 :6 0例维持性血透患者 (血肌酐≥ 70 0 μmol·L- 1 ) ,治疗组 (给予氯沙坦 5 0~ 10 0mg·d- 1 )及对照组 (给予非血管紧张素受体拮抗剂和非ACEI类降压药 )各 30例 ,记录用药前后各组患者血压 ,运用多普勒组织成像 (DTI)技术观察用药前后两组患者二尖瓣环峰值收缩速度 (VS)、收缩时间速度积分 (TVIS)、舒张早期速度 (VE)、舒张晚期速度 (VA)、VE VA 比值。结果 :治疗组及对照组患者治疗后血压均明显下降 ,二尖瓣环VS、TVIS、VE、VE VA ,则均明显上升 ;治疗组与对照组血压分别在治疗前、后相比并无明显差异 ;治疗前两组间二尖瓣环VS、TVIS、VE、VE VA 并无显著性差异 ,但在治疗12个月后 ,治疗组二尖瓣环VS、TVIS、VE、VE VA 则明显高于对照组。结论 :氯沙坦对行持续性血透的CRF患者具有良好的心脏保护作用 ,可有效改善其心功能 ,且不依赖于其降压作用 相似文献
135.
Y. Suzuki S. Ehara H. Shiraishi J. Nishida G. Murooka Y. Tamakawa 《Skeletal radiology》1997,26(2):128-130
The case of a 14-year-old girl with rhabdomyosarcoma of the right foot is reported. Plain radiography showed a large nonspecific
soft tissue tumor between the metatarsals with bowing of the metatarsals away from the mass. MR imaging showed a large soft
tissue mass involving the metatarsals. The findings were conflicting, because the tumor had an infiltrative soft tissue mass
and bowing of the metatarsals more suggestive of slow expansive growth. Bowing of short tubular bones may be a process similar
to cortical saucerization, which is typically seen in Ewing’s sarcoma, and it can be one of the findings of high grade neoplasms,
such as embryonal rhabdomyosarcoma. 相似文献
136.
皮肤软组织扩张器在整形外科中的应用 总被引:1,自引:0,他引:1
作者应用皮肤软组织扩张器进行软组织缺损修复13例,全鼻再造1例,除1例皮瓣远端血运不佳外,其余病例均获满意效果。本文介绍了皮肤软组织扩张术的优点及适应症,重点讨论了下列问题:①皮肤扩张面积的估计;②扩张囊埋植层次;③注射壶、连接导管的安放位置;④纤维囊的处理;⑤扩张皮瓣的正确设计。 相似文献
137.
138.
本文应用“冷沉淀”法制备纤维组织粘合剂。对纤维组织粘合剂中主要成份和含量进行了测定,并测定了主要理化性质,建立了动物实验模型,观察了实验兔对纤维粘合剂的反应。 相似文献
139.
M. Peiper D. Zurakowski C. Zornig 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1995,380(6):333-339
Soft tissue sarcomas (STS) tend to recur locally. In a series of 140 patients operated on during the past two decades with STS of the extremities and trunk, prognostic factors influencing local recurrence were determined. Statistical significance was evaluated for the quality of surgical resection (P<0.001), regional positive lymph nodes (P=0.03), and adjuvant radiotherapy (P=0.01) [for resection without wide margins (R1) and low-grade (G3) tumors]. In 1988, the surgical procedure was standardized. After 1987, local recurrence decreased significantly (P < 0.001). In subfascial tumors, local recurrence occurred far less in cases of compartmental resection than with wide excision. These data indicate that the course of patients with STS can be beneficially influenced by optimal therapy. Resection with wide margins in all three dimensions is the aim of sarcoma surgery. Postoperative radiation therapy is indicated in the case of R1 resection.
Lokalrezidive von Weichteilsarkomen an Extremitäten und Rumpf
Zusammenfassung Weichteilsarkome neigen zur Ausbildung von Lokalrezidiven. In einer Studie von 140 Patienten der letzten 20 Jahre mit Sarkomen an Extremitäten und Rumpf wurde untersucht, welche Faktoren das Auftreten von Lokalrezidiven beeinflussen. Statistische Signifikanz ergab sick fur die Qualität der chirurgischen Re sektion (R) (p<0,001), den regionalen Lymphknotenstatus (p=0,03) sowie eine adjuvante Strahlentherapie (p=0,01) [bei marginal resezierten (RI), niedrig differenzierten (G3) Tumoren]. 1988 wurde das chirurgische Vorgehen standardisiert. In der Zeit danach traten signifikant weniger Rezidive auf als davor (p < 0,001). Bei subfaszialer Lage traten Rezidive nach Kompartmentresektion wesentlich seltener auf als nach weiter Resektion. Der Krankheitsverlauf von Weichteilsarkomen ist also durchaus therapeutisch beeinflußbar. Ein dreidimensional weiter Sicherheitsabstand ist das entscheidende Therapieziel, eine Bestrahlung in R1-Situationen indiziert.相似文献
140.
Z. G. Natsvlishvili G. F. Sheremet'eva A. M. Babunashvili 《Bulletin of experimental biology and medicine》1991,112(6):1821-1825
All-Union Surgical Research Center, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR N. N. Malinovskii.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 112, No. 12, pp. 653–657, December, 1991. 相似文献