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91.
An experimental study of the effects of nerve root retraction on the posterior ramus 总被引:7,自引:0,他引:7
STUDY DESIGN: The histologic and ultrastructural changes in the posterior ramus after posterior lumbar surgery were studied in rabbits. OBJECTIVE: To investigate the structural changes in the posterior ramus after posterior lumbar surgery that may cause injury to the posterior ramus after the procedure. SUMMARY OF BACKGROUND DATA: Investigators in previous studies have pointed out that low back discomfort after lumbar discectomy relates to neurogenic changes and/or myogenic changes of paravertebral muscle. However, no previous study has demonstrated the effects of excessive nerve root retraction on spinal posterior rami. METHODS: Eighteen male Japanese White rabbits were used. The posterior ramus arising from the S1 nerve root was examined after exposure of the lamina only, fenestration, or retraction of the S1 nerve root, with light microscopy and transmission electron microscopy at 2, 4, and 6 weeks after the procedure. Results were compared with a those in control specimens that did not undergo the procedure. RESULTS: In the exposed group, no distinct difference was found compared with the control specimen. In the fenestration group, especially at 6 weeks, some attenuation and splitting of myelin sheaths was observed. In the retraction group, the structural alteration was most severe. Even at 2 weeks, fragmentation of many myelin sheaths was detected. Examination of specimens by electron microscopy indicated phagocytosis of myelinated fibers at 4 and 6 weeks. CONCLUSIONS: Findings showed that posterior lumbar procedures, including retraction of paravertebral muscle, fenestration of the lamina, and retraction of the nerve root affect the posterior ramus. Excessive retraction of the nerve root has an especially disastrous effect on the posterior ramus. Such a violent maneuver within the spinal canal must be avoided. 相似文献
92.
Marta Ruiz Hiroya Kobayashi Juan José Lasarte Jesús Prieto Francisco Borrás-Cuesta Esteban Celis Pablo Sarobe 《Clinical cancer research》2004,10(8):2860-2867
PURPOSE: The purpose of this research was to identify promiscuous T-helper cell determinants (THd) from carcinoembryonic antigen (CEA) to be used to prime T-cell help for cancer therapy. CEA was selected because this antigen is expressed in an important variety of carcinomas. EXPERIMENTAL DESIGN: Potential promiscuous THd from CEA were predicted using available computer algorithms. Predicted peptides were synthesized and tested in binding experiments to different HLA-DR molecules. Binder peptides were then used to prime T-cell responses both in vitro and in vivo. RESULTS: Twenty 15-mer peptides from CEA were predicted to bind to different HLA-DR molecules. The promiscuous character of these peptides was demonstrated in binding experiments. Fifteen of 20 peptides tested were able to bind to HLA-DR4, but only CEA (625-639) was shown to be presented after processing of recombinant CEA. CEA (625-639) was also found to be presented by HLA-DR53. Moreover, immunization of HLA-DR4 transgenic mice with CEA (625-639) in conjunction with class I epitope OVA (257-264), induced a CTL response specific of OVA (257-264). CONCLUSIONS: CEA (625-639) might be a relevant promiscuous THd peptide for cancer therapy. 相似文献
93.
In patients with reduced respiratory function, lung resection is associated with high risk because separate ventilation is generally needed for safe management. For patients with end-stage emphysema, intraoperative respiratory management is important and particularly difficult because neither incomplete oxygenation nor selective ventilation can be performed, so the operation may be interrupted. In this study, we assess the effectiveness of the percutaneous cardiopulmonary support (PCPS) system for lung volume reduction surgery in patients with severe hypercapnia (arterial carbon dioxide tension >50 mm Hg) and discuss the significance of PCPS for patients who are beyond the standard criteria for lung volume reduction surgery (LVRS). We studied 3 patients with severe hypercapnia due to emphysema who underwent volume reduction surgery. One patient was previously treated surgically for contralateral pneumothorax. All patients had a severe smoking history and were suspected to have fragile lungs. During the operation. PCPS provided sufficient support flow. Intraoperative management using PCPS was easy, and no severe complications were observed. One patient exhibited severe hemodynamic deterioration on postoperative Day 15. Other patients' PaCO2 improved postoperatively. One had a calcification of a femoral artery, but there was no trouble inserting a cannula. Bilateral or unilateral volume reduction surgery was performed under PCPS in patients with end-stage emphysema. We conclude that PCPS is an adjunct to LVRS, useful for intraoperative management of some patients with severe hypercapnea, and the LVRS indications can be extended. 相似文献
94.
Ichikawa Y Iida M Ebisui C Fujio C Yazawa K Hanafusa T Kouro T Seki K Nagano S 《Transplantation proceedings》2000,32(7):1982-1983
95.
Y Maegaki Y Maeoka A Seki M Ueno T Yamamoto K Takeshita 《European journal of paediatric neurology》1997,1(2-3):79-84
In two hemiplegic patients with acquired cerebral lesions, transcranial magnetic stimulation (TMS) was carried out to examine the contribution of the ipsilateral motor pathways to recovery from hemiplegia. A 13-year-old girl (patient 1) had acute hemiplegia due to a rupture of an arteriovenous malformation, and a 13-year-old boy (patient 2) had subacute hemiplegia due to a brain tumour. They showed complete upper limb palsy but recovered after therapy; patient 1 had slightly disabled motor function of the arm, and patient 2 recovered completely. Motor evoked potentials (MEPs) were recorded from the biceps brachii muscles on both sides. The MEPs of the paretic biceps were only elicited by TMS of the intact hemisphere at the beginning of recovery from hemiplegia, but not by TMS of the affected hemisphere. The MEP amplitudes increased and cortical representation areas for the paretic biceps by TMS were enlarged temporarily during recovery. They regressed in patient 1 and MEPs were not evoked at all in patient 2 after recovery. Conversely, MEPs were obtained by TMS of the affected hemisphere after recovery in both patients. These data indicate that ipsilateral motor pathways play a role in recovery from hemiplegia, especially at the beginning, and become inactivated when the contralateral motor pathways recover. 相似文献
96.
H. Matsui Y. Iitsuka K. Seki & S. Sekiya 《International journal of gynecological cancer》1997,7(5):400-404
Matsui H, Iitsuka Y, Seki K, Sekiya S. Etoposide (VP-16) as first-line,single agent chemotherapeutic drug in low-risk gestational trophoblasticdisease. Int J Gynecol Cancer 1997; 7: 400–404.
We reviewed the records of 73 patients with low-risk gestationaltrophoblastic disease (GTD) treated with etoposide from 1986 to 1995 at ChibaUniversity. All patients received courses of etoposide every 10 to 14 days until their human chorionicgonadotropin (hCG) concentrations had reached <1 mIU/ml or drug resistanceand/or unacceptable toxicityoccurred. Fifty-one patients (69.9%) were treated with chemotherapyalone and 22 patients (30.1%) also underwent planned hysterectomy.
Sixty-seven patients (92%) achieved a primary remission, while sixpatients (8%) required a change in drugs due to drug resistance (4patients, 5%) or toxicity (2patients, 3%). All 73 patients achieved complete remission. However, onepatient (1.4%) relapsed later.
We have demonstrated that etoposide is one of the most effective drugsagainst GTD and that the short-term toxicity is, except for alopecia,relatively mild and acceptable.Patients should, however, be informed of the possibilities of secondarymalignancies and followed-up cautiously. 相似文献
We reviewed the records of 73 patients with low-risk gestationaltrophoblastic disease (GTD) treated with etoposide from 1986 to 1995 at ChibaUniversity. All patients received courses of etoposide every 10 to 14 days until their human chorionicgonadotropin (hCG) concentrations had reached <1 mIU/ml or drug resistanceand/or unacceptable toxicityoccurred. Fifty-one patients (69.9%) were treated with chemotherapyalone and 22 patients (30.1%) also underwent planned hysterectomy.
Sixty-seven patients (92%) achieved a primary remission, while sixpatients (8%) required a change in drugs due to drug resistance (4patients, 5%) or toxicity (2patients, 3%). All 73 patients achieved complete remission. However, onepatient (1.4%) relapsed later.
We have demonstrated that etoposide is one of the most effective drugsagainst GTD and that the short-term toxicity is, except for alopecia,relatively mild and acceptable.Patients should, however, be informed of the possibilities of secondarymalignancies and followed-up cautiously. 相似文献
97.
Yoshie Nakanishi Junichi Kodama Keizo Tokumo Noriko Seki Yasunari Miyagi Mitsuo Yoshinouchi Hiroyuki Okuda Takafumi Kudo 《International journal of clinical oncology / Japan Society of Clinical Oncology》1997,2(4):219-223
Background The object of this study is to clarify the association of an angiogenic factor, PD-ECGF (platelet-derived endothelial cell
growth factor/thymidine phosphorylase), with clinicopathologic factors, in this case tumor angiogenesis, in epithelial ovarian
cancers.
Methods Tumor specimens were obtained at the time of surgery from the primary lesion in 60 patients with epithelial ovarian cancer.
Histologic cell types were assigned to tumors according to the World Health Organization classification: 26 were classified
as serous adenocarcinoma, 15 as endometrioid adenocarcinoma, 9 as mucinous adenocarcinoma, 9 as clear cell carcinoma, and
1 as undifferentiated carcinoma. Surgical staging was based on the international Federation of Gynecology and Obstetrics (FIGO)
staging system: 16 were stage I, 6 were stage II, 34 were stage III, and 4 were stage IV. Expression of PD-ECGF was evaluated
by immunohistochemical staining. Microvessel density was assessed by immunostaining for factor VIII-related antigen in the
most neovascularized area.
Results Stroma cells stained more strongly than cancer cells (80% vs. 33%). The immunopositivity of PD-ECGF in stroma cells was higher
in cases of advanced cancer. Expression of PD-ECGF in mucinous adenocarcinomas was significantly higher than that in serous
adenocarcinomas, while PD-ECGF expression in clear cell carcinomas was significantly lower. The microvessel density in the
cases with marked PD-ECGF-positive stroma cells was significantly higher than that in the cases with absent/minimal PD-ECGF-positive
stroma cells (P<0.05).
Conclusion The expression of PD-ECGF may play a crucial role in the promotion of angiogenesis in epithelial ovarian cancers. 相似文献
98.
Primary Mitral Valve Sarcoma in Infancy 总被引:2,自引:0,他引:2
K. Itoh T. Matsumura Y. Egawa M. Watanabe T. Ohshio A. Ohta Y. Hayabuchi K. Seki 《Pediatric cardiology》1998,19(2):174-177
Primary cardiac sarcoma is a rare tumor, found especially in children, particularly in the left side of the heart. This report
describes a rare case of primary mitral valve sarcoma in a 7-month-old male infant with hemiparesis and heart murmur who underwent
mitral valve replacement because of excessive invasion of the mitral valve by the tumor. The patient remains well, free of
recurrence and cerebral metastasis, and without adjuvant therapy 18 months after the operation. 相似文献
99.
During development in the chick embryo, luteinizing hormone-releasing hormone (LHRH) neurons migrate along the olfactory nerve from the olfactory epithelium to the forebrain. At embryonic day 5.5 (E5.5) to E6.0, the majority of LHRH neurons begin to enter the medial forebrain and then course dorsocaudally along the forebrain substance just beneath the pia matter in association with the somatostatin (SST)-positive fibers, which branch medially from the SST-positive olfactory nerve. By E6.5, the neurons and SST-positive medial branch of the olfactory nerve have proceeded toward the septal area. Intense immunoreactivity for the polysialylated form of neural cell adhesion molecule (PSA-NCAM) on both the LHRH neurons and the SST-positive fibers during this period suggests that this less adhesive form of NCAM is involved in the migratory process. This possibility was examined by using a polysialic acid (PSA)-specific endoneuraminidase. PSA removal did not alter the behavior or appearance of the SST-positive olfactory fibers within the migration pathway. However, it induced a significant deviation of migrating LHRH neurons from the regular path in the forebrain. The effect of PSA removal is more likely to involve changes in the interaction of the migrating neurons with a subset of the SST-positive olfactory fibers and/or other elements in the forebrain rather than an alteration in the pattern of their axonal substrate. On the basis of these results, it is suggested that PSA contributes to the specific pattern of LHRH neuronal migration in the forebrain by limiting interaction of these LHRH neurons with their surrounding environment. 相似文献
100.
Uei T Katou Y Shimizu N Yamanaka H Seki M Ibuki R 《Hinyokika kiyo. Acta urologica Japonica》2000,46(6):433-436
A 27-year-old female patient consulted us with chief complaints of difficulties of sexual intercourse and urination. On examination, the labia was found to be extensively fused at the midline, with a pinhole opening. We diagnosed it as labial adhesion. We operated on it under lumbar anesthesia. Four months after the operation, there were no symptoms of recurrence. Labial adhesion is thought to be caused by inflammation, lack of sexual activity and estrogen deficiency. It is not uncommon in children and post-menopausal women, but is extremely rare in reproductive women. 相似文献