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41.
OBJECTIVE: For retroperitoneal laparoscopic nephron-sparing surgery using a microwave tissue coagulator, it is helpful to know the relationship between the tumour, collecting system and vessels to prevent urinary leakage and vascular damage. We assessed the efficacy of multiplanar reformation and three-dimensional (3D) CT with the renal collecting system filled with contrast medium. METHODS: Fifteen patients with small renal tumours of less than 3 cm in diameter underwent dynamic CT examination ten minutes after injection of contrast medium of 30 ml. Multiplanar reformation, volume-rendered and maximum intensity projection images were created for determining operative approaches and for planning the operation. RESULTS: In all cases, the distance between the tumour and collecting system was measured on the multiplanar reformation. Accordingly, five cases were indicated for retroperitoneal laparoscopic nephron-sparing surgery using a microwave tissue coagulator. The remaining ten cases, due to the short distance (less than 10mm), were not considered good candidates for this procedure. The relationship between the tumour, collecting system and vessels was well shown on the volume-rendered and maximum intensity projection images. CONCLUSIONS: Multiplanar reformation and 3D-CT are able to give us an understanding of the surrounding structures. They are helpful in defining the indications for retroperitoneal laparoscopic nephron-sparing surgery using a microwave tissue coagulator and preoperative planning of nephron-sparing surgery.  相似文献   
42.
Although identification of the key artery that perfuses the spinal cord is essential to avoid occurrence of paraplegia after surgery on the thoracoabdominal aorta, reliable and noncomplicated measures are not yet available. A new method of determining it by using echocardiography with a saline injection into the lumbar artery was evaluated for feasibility and adequacy in a canine model. In two mongrel dogs, the abdominal aorta was opened and saline was directly injected into the lumbar arteries while the spinal cord was visualized by echocardiography through the intervertebral disc. When the echogenic or Doppler signal was detected in the spinal cord, the particular lumbar artery was determined as "positive", or as "negative" when the signal was not detected. After the dog was sacrificed, red resin was injected into the "positive" arteries and blue resin into the "negative" arteries. In the extracted spinal cord, the anterior and posterior spinal arteries were filled with red resin, rather than with blue resin, to indicate that the key arteries were correctly identified. There were multiple "positive" arteries, which were mainly located on the left side and accounted for approximately one-third of the entire lumbar arteries. The "negative" arteries mainly perfused the muscles around the vertebra. Injected resin came out of the adjacent lumbar arteries of the same category, suggesting that communication is present among the positive arteries, but independently of that among the negative arteries. Echo-guided identification of key arteries is technically feasible and correctly determines the key arteries in this preliminary canine model.  相似文献   
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44.
Juvenile delinquents often show poor impulse control and cognitive abnormalities, which may be related to disturbances in brain development due to head trauma and/or epilepsy. The aim of the present study was to examine the influence of head trauma and/or epilepsy on delinquent behavior. We examined 1,336 juvenile delinquents (1,151 males and 185 females) who had been admitted to the Nagoya Juvenile Classification Home, Aichi, Japan. Among them, 52 subjects with a history of epilepsy, convulsion or loss of consciousness, head injury requiring neurological assessment and/or treatment, or neurosurgical operation (head trauma/epilepsy group), were examined by electroencephalography and compared to subjects without these histories (control group) with respect to types of crime, history of amphetamine use, psychiatric treatment, child abuse, and family history. Among the 52 subjects, 43 (82.7%) showed abnormal findings. The head trauma/epilepsy group had significantly higher rates of psychiatric treatment (P<0.0001, OR=16.852, 95% CI=8.068-35.199) and family history of drug abuse (P<0.05, OR=2.303, 95% CI=1.003-5.290). Furthermore, the percentage of members who were sent to juvenile training school by the family court was significantly higher in the head trauma/epilepsy group (72.5%) than in the control group (38.9%, P<0.0001). The juvenile delinquents who had a history of head trauma and/or epilepsy showed a high prevalence of electroencephalograph abnormality, and higher rates of psychiatric treatment and family history of drug abuse, and were more likely to be sent to juvenile training school by the family court.  相似文献   
45.
The aim of this study was to evaluate CT and MRI findings in xanthogranulomatous cholecystitis (XGC) and to correlate the imaging findings with various pathologic parameters. The study included 13 patients with histopathologically confirmed XGC. The CT (n=13) and MRI (n=5) obtained in these patients were evaluated retrospectively. On CT, low-attenuation areas in the wall of XGC correlated with foam and inflammatory cells or necrosis and/or abscess in XGC. Areas of iso- to slightly high signal intensity on T2-weighted images, showing slight enhancement at early phase and strong enhancement at last phase on dynamic study, corresponded with areas of abundant xanthogranulomas. Areas with very high signal intensity on T2-weighted images without enhancement corresponded with necrosis and/or abscesses. Luminal surface enhancement (LSE) of gallbladder wall represented preservation of the epithelial layer. The early-enhanced areas of the liver bed on dynamic CT and MR images corresponded with accumulation of inflammatory cells and abundant fibrosis. Our results indicate that CT and MRI findings correlate well with the histopathologic findings of XGC.  相似文献   
46.
BACKGROUND: The treatment of patients with advanced hepatic hilar duct carcinoma is a challenging problem. The current study was performed to evaluate the outcome of patients with advanced hepatic hilar duct carcinoma who received external beam radiotherapy (EBRT) combined with transarterial chemotherapy and infusion of a vasoconstrictor. METHODS: Between April 1993 and December 2002, 23 patients with histopathologically confirmed hilar duct carcinoma entered the study. The median total dose of EBRT was 41.4 grays (Gy). Transarterial chemotherapy was performed twice during EBRT. It was comprised of an infusion of a cocktail of 20 mg of epirubicin, 10 mg of mitomycin C, and 500 mg of 5-fluorouracil and was administered 1 minute after injection of epinephrine via a catheter introduced in the hepatic arteries. After the combined treatment, the patients underwent biliary endoprosthesis after evaluation of the initial response to treatment by percutaneous transhepatic cholangiography (PTC). The initial responses based on PTC were classified into four categories: CR, no stenosis; PR, relief of stenosis/obstruction; NC, no change; and PD, progressive stenosis/obstruction. The outcome parameters were survival rates and time, as well as frequency and type of complications. RESULTS: Excluding 1 patient who discontinued the treatment, the initial responses of 22 patients were 1 CR (5%), 8 PR (36%), 11 NC (50%), and 2 PD (9%). The response rate was 41%. The overall survival rates at 1 year, 2 years, and 3 years after treatment were 59%, 36%, and 18%, respectively. CONCLUSIONS: The combination of radiotherapy, transarterial infusion chemotherapy, and concurrent infusion of a vasoconstrictor can be delivered safely with good efficacy for patients with advanced hilar duct carcinoma.  相似文献   
47.
BACKGROUND: Edaravone has potent free radical quenching and antioxidant actions. The agent has been recently in commercial use for acute ischemic stroke patients. In this study, we investigated the therapeutic effect of edaravone on severe carotid-territorial stroke. METHODS: Stroke patients with internal carotid artery occlusion and baseline NIH Stroke Scale Score > or =15 were treated for 14 days with drip intravenous infusion of edaravone (n=30) and were compared with a historical control cohort of similar patients (n=31). Glycerol was also administered to all patients in both groups. RESULTS: Infarct volume (P<0.02) and midline shift (P<0.02) on CT performed on day 2 of the patients treated with edaravone were smaller than those without edaravone. For patients with edaravone, infarct volume (P<0.0001) and midline shift (P<0.0001) on days 5-7 were greater than those on day 2. Hemorrhagic transformation of infarcts on day 2 was less severe in patients with than without edaravone (P<0.03). Within 14 days after the onset of stroke, 6 patients with edaravone (20%) and 14 without edaravone (45%) died directly of stroke (P<0.03). Among all patients, only two treated with edaravone were independent without any assistance 8 weeks after the onset. CONCLUSIONS: Edaravone was associated with delayed evolution of infarcts and edema in patients with severe carotid-territorial stroke and decreased mortality during the acute stage. The agent, however, failed to prevent evolution of infarcts and edema on later days, and did not significantly improve functional outcome among the surviving patients.  相似文献   
48.
We recently reported that Ascaris suum mitochondria express stage-specific isoforms of complex II: the flavoprotein subunit and the small subunit of cytochrome b (CybS) of the larval complex II differ from those of adult enzyme, while two complex IIs share a common iron-sulfur cluster subunit (Ip). In the present study, A. suum larval complex II was highly purified to characterize the larval cytochrome b subunits in more detail. Peptide mass fingerprinting and N-terminal amino acid sequencing showed that the larval and adult cytochrome b (CybL) proteins are identical. In contrast, cDNA sequences revealed that the small subunit of larval cytochrome b (CybS(L)) is distinct from the adult CybS (CybS(A)). Furthermore, Northern analysis and immunoblotting showed stage-specific expression of CybS(L) and CybS(A) in larval and adult mitochondria, respectively. Enzymatic assays revealed that the ratio of rhodoquinol-fumarate reductase (RQFR) to succinate-ubiquinone reductase (SQR) activities and the K(m) values for quinones are almost identical for the adult and larval complex IIs, but that the fumarate reductase (FRD) activity is higher for the adult form than for the larval form. These results indicate that the adult and larval A. suum complex IIs have different properties than the complex II of the mammalian host and that the larval complex II is able to function as a RQFR. Such RQFR activity of the larval complex II would be essential for rapid adaptation to the dramatic change of oxygen availability during infection of the host.  相似文献   
49.
Kikumori T  Imai T  Kaneko T  Sugimoto H  Shibata A  Hibi Y  Nakao A 《Surgery》2003,134(6):989-93; discussion 993-4
BACKGROUND: An accurate diagnosis of inferior vena cava (IVC) invasion is important in deciding the surgical strategy for a large adrenal tumor. We investigated the diagnostic value of intracaval endovascular ultrasonography (ICEUS) for invasion of the IVC by a large adrenal tumor. METHODS: Nine of 163 patients with adrenal and retroperitoneal tumors underwent ICEUS between 1993 and 2002. Intravascular ultrasonography was performed through the right femoral vein with the use of an 8Fr, 20-MHz transducer. The diagnostic criterion for detecting IVC invasion with ICEUS was identification of destruction of a single echogenic layer of the IVC wall or identification of an intracaval tumor mass. The ICEUS finding was confirmed by pathologic examination. RESULTS: The mean diameter of the tumors in 9 patients undergoing ICEUS and resection was 12.6 cm (range, 8.6-16 cm). Pathologic diagnosis varied: adrenocortical carcinoma, 4; malignant pheochromocytoma, 1; leiomyosarcoma, 1; metastatic lung cancer, 1; paraganglioma, 1; and neurilemmoma, 1. Vascular invasion was identified in 2 patients by ICEUS and confirmed by examination of resected specimens. The sensitivity, specificity, and positive predictive values of ICEUS for the diagnosis of the IVC invasion were 100%, 100%, and 100%, respectively. However, these values for computed tomography were 100%, 14%, and 25%, respectively; and for cavography, 100%, 57%, and 40%, respectively. CONCLUSIONS: ICEUS provides confirmatory information regarding tumor invasion of the IVC. This modality also can assist in formulating an operative strategy for large adrenal or retroperitoneal tumors.  相似文献   
50.
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