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51.
Computer-aided detection in computed tomography colonography: current status and problems with detection of early colorectal cancer 总被引:1,自引:0,他引:1
Morimoto T Iinuma G Shiraishi J Arai Y Moriyama N Beddoe G Nakijima Y 《Radiation Medicine》2008,26(5):261-269
PURPOSE: The aim of this study was to evaluate the usefulness of computer-aided detection (CAD) in diagnosing early colorectal cancer using computed tomography colonography (CTC). MATERIALS AND METHODS: A total of 30 CTC data sets for 30 early colorectal cancers in 30 patients were retrospectively reviewed by three radiologists. After primary evaluation, a second reading was performed using CAD findings. The readers evaluated each colorectal segment for the presence or absence of colorectal cancer using five confidence rating levels. To compare the assessment results, the sensitivity and specificity with and without CAD were calculated on the basis of the confidence rating, and differences in these variables were analyzed by receiver operating characteristic (ROC) analysis. RESULTS: The average sensitivities for the detection without and with CAD for the three readers were 81.6% and 75.6%, respectively. Among the three readers, only one reader improved sensitivity with CAD compared to that without. CAD decreased specificity in all three readers. CAD detected 100% of protruding lesions but only 69.2% of flat lesions. On ROC analysis, the diagnostic performance of all three readers was decreased by use of CAD. CONCLUSION: Currently available CAD with CTC does not improve diagnostic performance for detecting early colorectal cancer. An improved CAD algorithm is required for detecting flat lesions and reducing the false-positive rate. 相似文献
52.
垂直提升联合整形术治疗眼睑松弛 总被引:1,自引:2,他引:1
目的:从整体上解决眼周松驰的状况,改善眼眉形态,一次性完成眼周整形。方法:根据眼睑松驰程度,选择重睑,眉部、眼袋切口去除松驰的眼睑皮肤、多余脂肪;悬吊轮匝肌韧带,对眶缘新月形凹陷,释放眶脂充填、固定,紧缩眶隔筋膜,垂直向上、外上提升松驰之上睑,固定轮匝肌于眉弓骨膜或眶外缘骨膜上,皮肤切口向上垂直提升缝合,一次完成上、下睑松驰的矫正。结果:经治疗的34例上、下睑松驰患者术后上、下睑松驰均得到矫正,眉位置得到上提,下睑眶缘凹陷得到充填。眼角额部皱纹减少。结论:上、下睑松驰经联合手术垂直提升皮肤、肌肉、改善眉位置后,一次性完成了眼周整形,达到了较好的美学效果。 相似文献
53.
Decreased peroxynitrite inhibitory activity in induced sputum in patients with bronchial asthma 总被引:1,自引:2,他引:1
BACKGROUND: The production of peroxynitrite, an extremely potent oxidant, is increased in inflammatory lung disease. It is therefore important to measure antioxidant activity against peroxynitrite in epithelial lining fluid to examine the physiological effects of peroxynitrite in the airways of patients with asthma. This study was designed to determine whether peroxynitrite inhibitory activity in induced sputum is correlated with clinical characteristics and airway inflammatory indices in asthmatic patients. METHODS: Inflammatory indices were measured in induced sputum from 25 patients with asthma and 12 normal control subjects. Peroxynitrite inhibitory activity was also measured by monitoring rhodamine formation in sputum samples. RESULTS: Peroxynitrite inhibitory activity in induced sputum was significantly lower in asthmatic patients (52.4 (24.5)%) than in normal control subjects (92.1 (3.9)%, p<0.0001). Its activity was significantly correlated with forced expiratory volume in 1 second (FEV(1)) % predicted (r=0.774, p<0.0001) and bronchial hyperreactivity to methacholine (r=0.464, p=0.023). There was a significant negative correlation between peroxynitrite inhibitory activity and the degree of eosinophilic airway inflammation (% eosinophils, r=-0.758, p<0.0001; eosinophil cationic protein, r=-0.780, p<0.0001). CONCLUSIONS: Decreased peroxynitrite inhibitory activity occurs in induced sputum of asthmatic patients. Since even in patients with stable asthma the airway lining fluid lacks peroxynitrite inhibitory activity, large amounts of peroxynitrite, which are further increased during an acute asthma attack, would not be completely inactivated and asthmatic airways might have markedly increased susceptibility to peroxynitrite induced airway injury. 相似文献
54.
Prevention of Acute Lung Allograft Rejection in Rat by CTLA4Ig 总被引:6,自引:0,他引:6
Takeshi Shiraishi Yohichi Yasunami Megumi Takehara Toshimitsu Uede Katsunobu Kawahara Takayuki Shirakusa 《American journal of transplantation》2002,2(3):223-228
CTLA4 immunoglobulin (CTLA4Ig), which binds with a high affinity to B7-1 and B7-2, interrupts T-cell activation by inhibiting costimulatory signal. CTLA4Ig has been used in hopes of achieving antigen-specific tolerance induction in several solid organ transplants. In lung allograft rejection, however, its use has been controversial in terms of its effect on prevention of rejection. In the present study, the effect of murine CTLA4Ig on rat-lung allograft rejection was investigated. Rat left-lung transplantation was performed in an RT1 incompatible donor (Brown Norway; BN)-recipient (F344) combination. All allografts (n = 12) without any treatment were rejected within 7 days after transplantation. A single injection of murine form CTLA41g at a dose of 100 microg intraperitoneally (ip) or intravenously (iv) on day 1 post-transplantation achieved long-term graft survival (>90days) in 2/5 (40%) and 3/8 (38%), respectively. Moreover, 6/7 (86%) allografts in rats that received iv injection of 500 microg CTLA4Ig survived more than 90days. Allograft survival in the CTLA4Ig 500 microg iv recipient group was significantly longer than that in the no-treatment control or control immunoglobulin group (p <0.01). Four out of seven recipients bearing functional allografts for more than 90 days with the CTLA4Ig treatment accepted donor-specific skin grafts, whereas all third-party skin grafts (n=3) were rejected. Prevention of rat-lung allograft rejection could be achieved by intravenous administration of CTLA4Ig, resulting in long-term allograft survival with acceptance of donor-specific skin grafts. 相似文献
55.
胸腔镜加小切口行Heller手术治疗贲门失弛缓症 总被引:5,自引:0,他引:5
目的 探讨胸腔镜加小切口行 Heller手术治疗贲门失弛缓症的手术方法和效果 ,以提高手术疗效。方法 1996年 1月~ 2 0 0 0年 12月 ,对 3 7例经病史、食管镜和食管 X线钡餐造影确诊为贲门失弛缓症患者 ,在胸腔镜加小切口下行 Heller手术治疗 ,并进行随访观察。 结果 1例患者改行常规开胸手术。手术时间 1~ 3 .5小时 ,平均手术时间 1.8± 0 .4小时。所有患者术后均未发生食管漏和手术死亡 ,住院期间于胃肠道功能恢复后可正常进食 ,吞咽困难症状消失。至最后 1次随访 ,手术效果优 2 9例 ( 78% ) ,良 5例 ( 14 % ) ,差 3例 ( 8% ) ,后者术后 3个月因吞咽困难复发行食管扩张 ,发生食管反流 4例 ( 11% ) ,但不需手术或药物治疗。 结论 胸腔镜加小切口 Heller手术治疗贲门失弛缓症具有良好的效果。 相似文献
56.
Development of port-site metastasis after pneumoperitoneum 总被引:7,自引:0,他引:7
Hirabayashi Y Yamaguchi K Shiraishi N Adachi Y Kitamura H Kitano S 《Surgical endoscopy》2002,16(5):864-868
Background: Port-site metastasis is a critical problem in laparoscopic cancer surgery; the pathogenesis and means of prevention
are still unclear. The aim of this study was to clarify by scanning electron microscopy the initial morphologic changes in
the development of port-site metastasis. Methods: Fifteen nude mice were injected with human gastric cancer (MKN 45) cells.
Mice were killed on days 0, 3, and 8 (n = 5 each day) after intraperitoneal injection of 5 × 105 cancer cells and carbon dioxide
(CO2) pneumoperitoneum at 4–6 mmHg for 20 min. The abdominal wall with the port sites was harvested and examined under both
light and scanning electron microscopy. Results: Immediately after CO2 pneumoperitoneum (day 0), the abdominal peritoneum
was peeled away and the muscular layer was destroyed at the port site in all mice. Several cancer cells were attached to the
injured port sites. On day 3, the subperitoneal tissue and muscular layer defects were replaced by granulation tissue, and
several cancer cells were observed in the subperitoneal tissue. On day 8, a small nodule was macroscopically visible at the
port site; it was completely covered by mesothelial cells and consisted of numerous cancer cells. Conclusions: Free cancer
cells appear to attach to the injured port sites immediately after CO2 pneumoperitoneum, and these are associated with the
development of port-site metastasis after laparoscopic cancer surgery. 相似文献
57.
Ueno S Tanabe G Nuruki K Oketani M Komorizono Y Hokotate H Fukukura Y Baba Y Imamura Y Aikou T 《Journal of Hepato-Biliary-Pancreatic Surgery》2002,9(4):469-477
Background/Purpose: Given that the prognosis of patients with hepatocellular carcinoma (HCC) complicating severe cirrhosis remains uncertain,
particularly with regard to various therapeutic strategies, we have evaluated the prognosis in a series of patients with homogeneous
diagnostic and therapeutic histories.
Methods: From 1990 to 1998, 411 consecutive HCC patients associated with Child class B and class C cirrhosis who did not have lymph
node or distant metastasis were treated by partial hepatectomy (PH; n = 48), percutaneous ethanol injection (PEI; n = 105), transcatheter arterial chemoembolization (TACE; n = 189), chemotherapy, or supportive care (chemo/supportive; n = 69). Univariate survival curves were estimated. The Cox model, stratified by the treatment groups, was used for multivariate
analysis.
Results: As of January 1999, 305 patients (74.2%) had died. Overall median survival was 23.4 months. There were statistically significant
differences between the survival times of patients receiving PH or PEI and TACE, as compared with those receiving chemo/supportive
care. According to multivariate analysis, the independent predictive survival factors were: albumin level (≥3.0 g/dl), esophageal
varices (i.e., absence), tumor size (≤3.0 cm), tumor number (solitary), and α-fetoprotein (AFP) level (<400 ng/ml). According
to the total number of risk factors and the median survival, all patients were divided into four subgroups. For the score
0 group (no risk factor group), 3- and 5-year survival rates were 83.1% and 68.0% for PH, and 87.5% and 62.3% for PEI, respectively.
In the score 1–2 group (one or two risk factors), survival rates at 3 and 5 years were 53.1% and 40.3% for PH, 54.8% and 33.2%
for PEI, and 35.4% and 22.8% for TACE, respectively. For patients with a score of 3 or more, there were no differences among
the treatment groups, excluding those with chemo/supportive care.
Conclusions: These findings indicate that, in HCC patients with complicating Child B and C cirrhosis, PEI and PH should be considered
first for subgroups of patients with scores (risk factors) of 0–2, as an acceptable survival rate was obtained in such patients.
Therefore, the advantages and disadvantages of these therapies regarding tumor size and location should be counterbalanced.
In patients with a score of 3 or more, TACE, when possible, could be a first choice because of its applicability and its adjuvant
nature with respect to other therapies such as liver transplantation.
Received: February 6, 2002 / Accepted: May 22, 2002
Offprint requests to: S. Ueno 相似文献
58.
59.
目的 研究手指末节指掌侧浅静脉分布规律,指导指末节离断再植术.方法 取100例手指标本分别进行乳胶灌注显微解剖法、断层解剖法、明胶-氧化铅灌注显微-解剖加X线摄片法研究指末节掌侧浅静脉的解剖学特点.临床对10例13指的离断末节指,进行吻合掌侧浅静脉的再植术.结果 在甲根水平通常可以找到1~3条指掌侧浅静脉,管径为0.2~0.5 mm.10例13指末节指离断再植均获成功.术后随访3~18个月,外观功能良好.结论 末节指掌侧浅静脉分布具有规律性,末节指再植吻合掌侧静脉有利于提高再植的成功率,并能减少其他静脉回流方法所带来的并发症. 相似文献
60.
Takana Koshi Seiji Ohtori Gen Inoue Toshinori Ito Masaomi Yamashita Kazuyo Yamauchi Munetaka Suzuki Yasuchika Aoki Kazuhisa Takahashi 《European spine journal》2010,19(4):593-600
Degeneration of lumbar intervertebral discs is thought to be a cause of low back pain. Studies have found that a cause of
discogenic low back pain is intervertebral disc inflammation and axonal growth of afferent fibers innervating the disc. Lumbar
spine fusion for chronic discogenic low back pain is considered an effective procedure. However, no study has investigated
the mechanism of pain relief. We did this by applying Fluoro-Gold (FG) to the ventral aspect of the L4–L5 intervertebral discs
of 40 rats. We exposed the nucleus pulposus to the annulus fibrosus in a disc punctured model. Rats were divided into 4 groups.
Group A: Punctured intervertebral disc with sham posterolateral fusion (PLF) (n = 10), Group B: Punctured intervertebral disc with PLF (n = 15), Group C: Normal intervertebral disc (no puncture) with PLF (n = 10), and Group D: Normal disc (no disc puncture) with sham PLF (n = 5). Four weeks after surgery, bilateral L1–L5 dorsal root ganglia (DRGs) were stained with growth-associated protein 43
(GAP43), a marker of axonal growth, and calcitonin gene-related peptide (CGRP), a neuropeptide marker of pain. Bone union
was evaluated using X-ray imaging. Of the FG-labeled neurons, the proportions of GAP43- and CGRP-immunoreactive (IR) neurons
in Group A were significantly higher than in Group D (P < 0.05). The proportions of GAP43- and CGRP-IR neurons in bone union rats in Group B were significantly lower than in nonunion
rats in Group B and in the rats in Group A (P < 0.05). No significant differences in GAP43- and CGRP-IR neurons were observed between bone union and nonunion rats in Group
C and the rats in Group D (P > 0.05). PLF is strongly related to the downregulation of GAP43 and CGRP expression. Therefore, PLF may suppress the increase
of inflammatory neuropeptides and the process of axonal growth. Moreover, these results may explain, in part, the mechanism
of pain relief following lumbar spinal fusion for chronic discogenic low back pain in humans. 相似文献