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排序方式: 共有8204条查询结果,搜索用时 17 毫秒
91.
Hiroshi Yoshizu M.D. Eriya Okuda M.D. Yoshiyuki Haga M.D. Nobuo Hatori M.D. Atsuhiro Mitsumaru M.D. Susumu Tanaka M.D. F.I.C.A. 《The International journal of angiology》1996,5(1):15-18
We studied the protective effects of intrathecally administered lidocaine against ischemic spinal cord injury during surgery. Seven patients (mean age 63.7 years, malefemale=61) with descending thoracic aortic aneurysms underwent reconstructive surgery. Following intrathecal lidocaine administration (10 ml), the operation was performed under femorofemoral bypass with an oxygenator. The aorta was cross-clamped at the distal end of the descending thoracic aorta and the proximal end of the lesions. The cross-clamping time was 47.1±23.3 minutes (mean ± SD). The operative procedure was total replacement of the descending thoracic aorta in five cases and patch closure in two. There were no operative deaths but paraparesis developed in two cases of total replacement. Neurological deficit was transient and disappeared in one case. In the other case, with 88 minutes of normothermic aortic cross-clamping, paraparesis gradually improved but was persistent after 7 months of follow-up. Graft anastomosis at the distal aortic arch was time consuming in this case and presumably caused prolonged spinal cord ischemia. Intrathecal administration of lidocaine was likely to reduce ischemic spinal cord injury and increase tolerance of the spinal cord to ischemia caused by prolonged aortic cross-clamping. This method was considered to provide a useful assistance to expand the safety limit of spinal cord ischemia in surgical reconstruction of the descending thoracic aorta requiring aortic occlusion. Tissue protective effects of intrathecal lidocaine administration may be further augmented by combining with deep hypothermia. 相似文献
92.
Makoto Komura Yoshiaki Tsuchida Toshiro Honna Yoshiyuki Kamii Shu-ichiro Kitahara Shin-pachi Ishizone 《Pediatric surgery international》1993,8(2):157-161
A case showing many of the typical visceral features of cloacal exstrophy is reported. The patient had fn imperforate anus, a cecal-cloacal fistula, dehiscence of the pubiic symphysis, and lumbosacral spina bifida with synsingomyelia, but the lower abdominal wall was intact without any visceral extroversion. The pertinent literature was reviewed, and it was found that this case corresponded to t typical case of completely covered cloacal exstrophy. Only six cases, including the present one, have so far been reported in the literature. From a clinical viewpoint, it apparently occupies an intermediate position in the wide spectrum of cloacal anomalies between classical cloacal exstrophy and imperforate anus with recto-cloacal fistula, but anatomatically and embryologically it is definitely a variant of cloacal exstrophy. In other words, it looks like an imperforate anus with recto-cloacal exstrophy, but should be treated as a variant of loacal exstrophy. The anatomy, classification, embryology, diagnosis, and management of this peculiar surgical condition are discussed, and recognition of this entity is urged. 相似文献
93.
Honda O Nishimura M Tomiyama N Johkoh T Mihara N Kozuka T Naito H Hamada S Kagawa K Nishida T Ichikawa Y Yamamoto S Nakamura H 《Investigative radiology》2000,35(9):534-538
RATIONALE AND OBJECTIVES: To investigate whether expiratory high-resolution computed tomography (HRCT) is more useful than inspiratory HRCT for the detection of early-phase diffuse alveolar damage. METHODS: Eleven anesthetized rabbits were scanned with both inspiratory and expiratory HRCT every 30 minutes during mechanical ventilation. Ten rabbits were killed after the detection of pulmonary abnormalities on both inspiratory and expiratory HRCT. The remaining rabbit was killed when the pulmonary abnormalities appeared only on expiratory HRCT. RESULTS: In four cases (36%), the abnormal findings were detected earlier on expiratory HRCT than on inspiratory HRCT. In seven cases (64%), the abnormalities appeared simultaneously on inspiratory and expiratory HRCT. In all 11 cases, the histopathological changes of areas with abnormal CT findings corresponded to the exudative or proliferative phase of diffuse alveolar damage. CONCLUSIONS: Expiratory HRCT has the potential to detect the abnormalities of diffuse alveolar damage earlier than inspiratory HRCT. 相似文献
94.
Yusuke Demizu Kazufumi Kagawa Yasuo Ejima Hideki Nishimura Ryohei Sasaki Toshinori Soejima Toshihiro Yanou Masakazu Shimizu Yoshiya Furusawa Yoshio Hishikawa Kazuro Sugimura 《Radiotherapy and oncology》2004,71(2):207-211
We investigated the biological effect of combining carbon-beam and X-ray in vitro. The results showed that when we employed Gray equivalent as the indication of therapeutic dose, the effects could be explained with simple additive way in the treatment plan. This fact provides important information about the combined therapy of carbon-beam and X-ray. 相似文献
95.
Expression level of valosin-containing protein is strongly associated with progression and prognosis of gastric carcinoma. 总被引:9,自引:0,他引:9
Shinji Yamamoto Yasuhiko Tomita Yoshihiko Hoshida Shuji Takiguchi Yoshiyuki Fujiwara Takushi Yasuda Masahiko Yano Shoji Nakamori Masato Sakon Morito Monden Katsuyuki Aozasa 《Journal of clinical oncology》2003,21(13):2537-2544
PURPOSE: Valosin-containing protein (VCP; also known as p97) was shown to be associated with antiapoptotic function and metastasis via activation of nuclear factor kappa-B signaling pathway. In this study, association of VCP expression with recurrence of gastric carcinoma (GC), in which lymphatic vessels are the main route of spread, was examined. PATIENTS AND METHODS: VCP expression in 330 patients with GC (242 males and 88 females) with ages ranging from 26 to 81 years (median, 60 years) was analyzed by immunohistochemistry, in which staining intensity in tumor cells was categorized as weaker (level 1) or equal to or stronger (level 2) than that in endothelial cells. RESULTS: Ninety-four (28.7%) patient cases showed level 1 and 233 patient cases (71.3%) showed level 2 VCP expression. Patients with level 2 expression showed higher rates of large tumor size (P <.0001), undifferentiated histologic subtype (P <.05), presence of vascular and lymphatic invasion (P <.0001 for both), presence of lymph node metastasis (P <.0001), deep tumor invasion (P <.0001), and poorer disease-free and overall survivals (P <.0001 for both) compared with those with level 1 VCP expression. Multivariate analysis revealed VCP expression level as an independent prognosticator for disease-free and overall survival. VCP level was an indicator for disease-free and overall survival in the early (pT1; P <.01 and P <.05, respectively) and advanced (pT2-4; P <.05 for both) group of pathologic tumor-node-metastasis system classification. CONCLUSION: The prognostic significance of VCP expression level in GC was demonstrated. 相似文献
96.
Reduced MLH1 expression after chemotherapy is an indicator for poor prognosis in esophageal cancers.
Kentaro Kishi Yuichiro Doki Masahiko Yano Takushi Yasuda Yoshiyuki Fujiwara Syuji Takiguchi Sontae Kim Ichiro Higuchi Morito Monden 《Clinical cancer research》2003,9(12):4368-4375
PURPOSE: Loss of function or expression of the mismatch repair gene MLH1 has been implicated in experimentally acquired resistance to cisplatin (CDDP) and other anticancer agents. The clinical significance of MLH1 expression was evaluated in advanced thoracic squamous cell carcinoma of the esophagus (ESCC) treated by neoadjuvant chemotherapy. EXPERIMENTAL DESIGN: We investigated MLH1 and P53 expression by immunohistochemistry in the surgical specimens of 107 patients who had undergone preoperative chemotherapy using CDDP along with 5-FU and ADM. These findings were correlated with the clinical outcome for this treatment. Biopsy samples before chemotherapy in 20 of these patients, and another 43 surgical specimens without chemotherapy, were also examined as control samples. RESULTS: In surgical specimens of ESCC, low MLH1 expression was not frequent without chemotherapy, whereas it was commonly observed after chemotherapy (14 versus 37%, P = 0.0057). Comparison between samples before and after chemotherapy revealed that MLH1 expression was unchanged during chemotherapy in 12 of 20 patients (60%) but was from high to low in 8 of 20 patients (40%). In the surgical specimen after neoadjuvant chemotherapy, MLH1 expression was not correlated with any clinicopathological factors, including the response to chemotherapy. However, low MLH1 showed poorer prognosis than high MLH1 (5-year survival 40.6 versus 19.3%, P = 0.0393), and in multivariate analysis, MLH1 was an independent prognostic factor for this multimodal treatment, following lymph node metastasis and clinical response to chemotherapy. Positive p53 expression, which was not affected by chemotherapy, was weakly associated with a poor response and clinical outcome, although this trend was not significant. CONCLUSIONS: In advanced ESCC, expression of MLH1 is reduced during CDDP-based chemotherapy, and this may partly account for poor postoperative survival. 相似文献
97.
98.
Homotypic Adhesion through Carcinoembryonic Antigen Plays a Role in Hepatic Metastasis Development 总被引:2,自引:0,他引:2
Toshiaki Yoshioka Takashi Masuko Hitoshi Kotanagi Osamu Aizawa Yuri Saito Hiroshi Nakazato Kenji Koyama Yoshiyuki Hashimoto 《Cancer science》1998,89(2):177-185
We established a cell line with high metastatic potential to the liver (LS-LM4) after four successive repetitions of splenic injection of liver-metastatic cells in SCID mice. This cell line strongly expressed CEA and showed increased homotypic adhesion as compared with the parent cell line (LS174T). To examine the role of CEA in the increased homotypic adhesion, LS-LM4 cells were treated with anti-CEA antibody and subjected to an in vitro adhesion and aggregation assay. Further, to study the role of CEA in the hepatic metastasis of cells with high metastatic potential, LS-LM4 cells were treated with anti-CEA antibody, and the inhibition of hepatic metastasis after splenic injection in vivo was examined. There was a 62% decrease in the homotypic adhesion of anti-CEA antibody-treated (100 μg/ml) LS-LM4 cells under a Ca2+ -free condition as compared with the control ( P <0.01). Anti-CEA antibody (100 μg/ml) inhibited cell aggregation under a Ca2+ -free condition ( P <0.05). Treatment with anti-E-cadherin antibody (60 μ/ml) plus anti-CEA antibody (100 μg/ml) inhibited cell aggregation more potently than anti-E-cadherin antibody treatment alone in the presence of Ca2+ . In vivo , there was a 75% decrease in the number of hepatic metastatic nodules in the G125 anti-CEA antibody-treated group as compared with the control group ( P <0.01). Similarly, there was a 40% decrease in the diameter of metastatic nodules and there was a 90% decrease in total tumor volume of hepatic metastasis in the G125 anti-CEA antibody-treated group as compared with the control ( P <0.01). These results suggest that increased metastatic potential to the liver is at least partly due to increased homotypic binding mediated by CEA. 相似文献
99.
Absence of p53 Overexpression and Favorable Response to Cisplatin-based Neoadjuvant Chemotherapy in Urothelial Carcinomas 总被引:3,自引:0,他引:3
Yoshiyuki Kakehi Enver Özdemir Tomonori Habuchi Hirohiko Yamabe Takayuki Hashimura Yoshitaka Katsura Osamu Yoshida 《Cancer science》1998,89(2):214-220
It has been controversial whether cancer cells harboring loss or inactivation of the tumor suppressor p53 are resistant or sensitive to DNA-damaging agents including cisplatin and doxorubicin. Overexpression of mdm2 oncoprotein, a negative regulator of p53, is assumed to be an alternative to p53 dysfunction. Archival urothelial carcinoma specimens obtained from 60 patients prior to cisplatin-based chemotherapy were immunohistochemically studied for overexpression of p53 and mdm2. Thirty-two patients (group I) were treated with chemotherapy in the neoadjuvant setting, while 28 patients (group II) underwent chemotherapy for distant metastases or inoperable locoregional tumors. In group I, the responsiveness was correlated with staining status of p53 ( P =0.0225) and the combination of p53 and mdm2 ( P =0.0497). Negative staining of p53 and negative for both p53 and mdm2 could have predicted favorable response to chemotherapy in 16 of 18 (88.9%) and in 12 of 13 (92.3%) tumors, respectively. On the other hand, p53-positive and p53 and/or mdm2-positive staining could have predicted poor response only in 7 of 14 (50.0%) and 8 of 19 (42.1%) tumors, respectively. Disease-specific survival of the p53-negative group was significantly superior to that of the p53-positive group ( P =0.0086). Difference in survival did not become more significant when overexpression of mdm2 was taken into consideration ( P =0.0456). In contrast, in group II, there was no correlation of responsiveness to chemotherapy or survival with p53- or p53/mdm2-staining status. The patients with urothelial carcinomas negative for overexpression of p53 will benefit from neoadjuvant chemotherapy. From clinical viewpoint, however, p53 status alone or the combination of p53 and mdm2 status is not enough to identify those patients who will not benefit from the treatment. 相似文献
100.
Tetsuya Shirokawa Yoshiyuki Ishida Wataru Matsunaga Sadamu Nakai Ken-ichi Isobe 《Nihon shinkei seishin yakurigaku zasshi》2005,25(1):43-48
The locus coeruleus (LC), located within the caudal pontine central gray, is composed of noradrenaline-containing neurons. The axons of these neurons form extensive collateral branches that project widely to many brain sites. The function of the LC is still unclear at present, however, LC neurons are known to exhibit marked axonal regeneration and sprouting in response to brain damage. We investigated the age-related changes in noradrenergic innervations of the frontal cortex, using in vivo electrophysiological techniques and immunohistochemistry. While noradrenergic innervations gradually decreased with age in the frontal cortex, a high degree of sprouting occurred in the LC axon terminals in middle age. Neither the electrophysiological properties of LC neurons nor NA levels in the frontal cortex changed with age. These findings suggested that the LC neurons preserve a strong capacity to remodel their axon terminals even in the aging brain. Exogenous brain-derived neurotrophic factor (BDNF) infusion caused a marked increase in the density of noradrenergic axon in the aged brain, but no trophic action of BDNF was observed in the young or middle-aged brain. The result suggests that BDNF is necessary for the maintenance of noradrenergic innervations in the aged brain. 相似文献