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971.
A case of bilateral obturator hernias which was diagnosed by ultrasonography (US) and computed tomography (CT), and repaired by a retropublic extraperitoneal operative approach under spinal anesthesia is reported herein. A 91-year-old woman presented with lower abdominal and left groin pain consistent with a Howship-Romberg sign. US demonstrated an image of the bowel projecting from the small pelvic space to the left thigh with a to-and-fro movement of the bowel contents. The definitive diagnosis of an incarcerated left obturator hernia was made by CT which also revealed a mass in the right obturator foramen. Surgery was performed through a retropublic extraperitoneal approach under spinal anesthesia. No necrosis was observed in the incarcerated bowel and resection was not necessary. A simple hernial sac was found in the right obturator canal. The operation using the retropublic extraperitoneal approach was successful and we believe it to be the most effective procedure for obturator hernias which have been diagnosed early.  相似文献   
972.
Tc-99m tetrofosmin is a lipophilic, cationic perfusion imaging agent that changes to Tl-201 in detecting coronary artery disease during exercise testing. The purpose of this study is to evaluate the usefulness of Tc-99m tetrofosmin dipyridamole stress imaging combined with low level exercise for the detection of coronary artery disease. We examined 42 patients and 10 normal volunteers who also underwent coronary angiography. A one-day protocol was used: in the stress study, 296 MBq of tetrofosmin was injected and in the rest study 888 MBq was injected. After intravenous administration of dipyridamole (0.142 mg/kg/min for 4 minutes), the patient was exercised on a bicycle ergometer for 3 min (25 Watts). Tetrofosmin was injected 2 minutes after dipyridamole infusion during the exercise. Single photon emission computed tomographic images were obtained 30 minutes after the tracer injection. Images were interpreted as abnormal in 36 of 42 patients with coronary artery disease, and normal in all of 10 normal volunteers. The overall sensitivity of detection of coronary artery disease was 83.3% and the normalcy rate was 100%. The diagnostic values for the detection of significant stenosis in the three major arteries were: LAD sensitivity 83%, specificity 92%; LCX sensitivity 47%, specificity 91%; RCA sensitivity 75%, specificity 83%. Of the 66 arteries with more than 50% stenosis, 48 arteries were correctly identified. Of the 36 with more than 70% stenosis, 31 were identified. Scintigraphic evidence of multivessel disease was found in only 9 patients (50%). A protocol of Tc-99m tetrofosmin SPECT combined with low level exercise after dipyridamole is therefore useful for the detection of the coronary artery disease.  相似文献   
973.
PURPOSE: To investigate the technical outcome of radiologic catheter placement with use of a side-hole catheter with distal fixation for hepatic arterial infusion chemotherapy. MATERIALS AND METHODS: Between January 1993 and September 1999, 426 patients were referred to our department to undergo intraarterial infusion chemotherapy for unresectable malignant liver tumors. A subclavian artery was exposed under local anesthesia and a catheter was inserted. After inserting the tip of the side-hole catheter into the gastroduodenal artery, splenic artery, or peripheral branch of the hepatic artery, the catheter tip was fixed to the vessel with use of coils and a mixture of n-butyl cyanoacrylate (NBCA) and iodized oil. The proximal end of the catheter was connected to an implanted port, and the port system was embedded subcutaneously. RESULTS: Placement was successful in 425 of 426 patients (99.8%) in a mean time of 76 minutes. Catheter dislodgement was noted in 12 patients (2.8%). Cumulative patency rates of the hepatic artery calculated according to the Kaplan-Meier method for the entire group were 91.0%, 81.4%, and 58.1% at 6 months and 1 and 2 years, respectively. Complications related to catheter placement were observed in nine cases and included dysfunction of the implanted system (n = 3), significant bleeding around the implanted port (n = 2), improper infusion of NBCA and iodized oil (n = 2), and cerebral infarction (n = 2). CONCLUSION: Radiologic catheter placement via a subclavian artery with side-hole catheter placement with distal fixation for hepatic arterial infusion chemotherapy is a highly successful procedure with a reduced risk of catheter dislodgment and arterial occlusion.  相似文献   
974.
PURPOSE: Several different anti-hypertensive regimens have been introduced for the prevention of systemic hyperdynamic responses after electrically induced seizures. In the present study, the effects of anti-hypertensive medications on cerebral circulation were studied. METHODS: Systemic blood pressure was controlled by several anti-hypertensive medications, nicardipine, prostaglandin EI, alprenolol and nitroglycerin, in 30 patients (150 electroconvulsive therapy trials). Changes in cerebral blood flow velocity were measured by transcranial Doppler sonography of the right middle cerebral artery from the start of anesthesia to 10 min after the electrical shock. RESULTS: Administration of a Ca2+ antagonist, nicardipine, or prostaglandin EI did not alter the augmented cerebral blood flow velocity after the seizure. However, a beta-adrenergic blocking agent, alprenolol (P<0.05) or nitroglycerin (P<0.01) partially inhibited the increase in cerebral blood flow velocity. Maximal blood flow velocity was 133% larger than the pre-anesthesia value in the control group, 109% in the nicardipine group, 113% in the prostaglandin EI group, 72% in the alprenolol group, and 45% in the nitroglycerin group, respectively. The increase in cerebral blood flow velocity after electrically induced seizure was independent of systemic blood pressure. Internal jugular venous saturation (SjO2) was increased, and difference in arterial and venous concentrations of lactate was not altered in all groups. CONCLUSIONS: Cerebral hemodynamics is altered by ECT, even when systemic hemodynamics are stabilized by antihypertensive medication. Although the effects of antihypertensive medicine on cerebral hemodynamics are variable, systemic blood pressure control by these agents does not induce cerebral ischemia after ECT.  相似文献   
975.
PURPOSE: To identify the drug infusion vessel for use in obtaining the best drug distribution in arterial infusion chemotherapy for advanced pancreatic cancer. MATERIALS AND METHODS: In 16 cases of advanced pancreatic cancer (pancreatic head, n = 12; pancreatic body and/or tail, n = 4), computed tomography during arterial injection of contrast material was performed at the time of angiography. The sites of catheter placement were celiac artery, superior mesenteric artery, and their branches, such as gastroduodenal artery, inferior pancreatico-duodenal artery, or dorsal pancreatic artery. RESULTS: In the cases of pancreatic head cancer, all except one with hepatomesenteric vascular variation were supplied by the celiac artery and superior mesenteric artery (dual supply). In the cases of pancreatic body and/or tail cancer, two were supplied by celiac artery alone and two showed dual supply. In the cases of pancreatic head cancer, when the areas supplied by the main trunk were compared with those supplied by its branches, three of nine cases on the celiac artery side and four cases on the superior mesenteric artery side showed that the areas were not consistent, with a partial defect observed in the areas supplied by branches of the superior mesenteric artery. In the cases of pancreatic body and/or tail cancer, on both sides, one of two cases was not consistent. CONCLUSIONS: To achieve optimal drug distribution in arterial infusion chemotherapy for advanced pancreatic cancer, drug infusion via both the celiac artery and superior mesenteric artery is required in the majority of cases. In many cases, optimal drug distribution is not attainable with drug infusion via a branch; therefore, drug infusion should be administered via the main trunk.  相似文献   
976.
This study confirms the presence of a novel variable number of tandem repeats polymorphism, designated as HumDN1, in intron 4 of the human deoxyribonuclease I (DNase I) gene. Genotyping was performed without difficulty by PCR-amplification and separation by agarose gel electrophoresis in 423 Japanese, originating from four geographically diverse areas in Japan, and 89 Germans. The HumDN1 allele variability was due to different numbers of 56-bp repeat sequences, and five different alleles were distinguished with apparent size between 364 and 588 bp. Although there was a general uniformity for the polymorphism in the Japanese population, significant differences in genotype distribution were found between the Japanese and German populations. Furthermore, linkage disequilibrium between the HumDN1 and DNase I protein polymorphisms was revealed.  相似文献   
977.
OBJECTIVE: To compare the results of CT and barium enema examination in the diagnosis of peritoneal metastasis from gastric carcinoma. MATERIALS: Peritoneal metastases were pathologically confirmed in nine patients with gastric carcinoma who had had abdominal CT and barium enema examinations prior to surgery. METHODS AND RESULTS: Five patients were reported to have colonic wall rigidity on preoperative barium enema examination. Review of the images indicated that six cases showed rigidity. On the other hand, no CT findings suggestive of peritoneal metastasis were reported in eight patients without ascites. No patients were indicated to have intraperitoneal nodules. For the retrospective evaluation, we changed the diagnostic procedure: the CT window setting was changed in wide window width (from 250 Hounsfield units (HU) to 400HU)and low window level (50-60HU to 0 HU), and reading mode was changed to a cine paging mode with a picture archiving and communication system (PACS) instead of hard-copy review. It followed that intraperitoneal nodules suggestive of peritoneal metastasis were detected in eight patients. CONCLUSION: On conventional image reading, barium enema examination is of greater assistance than CT examination for detecting peritoneal metastasis from gastric carcinoma. However, the new CT reading method with PACS is more sensitive than barium enema examination for diagnosing peritoneal metastasis.  相似文献   
978.

Objectives

Our research group developed new PET scanner with semiconductor detectors for high spatial resolution with low scatter noise. On head and neck cancer (HNC) surgery, FDG-PET may often provide false-positive findings in cervical node involvements. Accordingly, we assessed diagnostic accuracy using this new scanner in the HNC patients as compared with the conventional lutetium oxyorthosilicate (LSO) PET.

Methods

We prospectively studied FDG imaging in 35 HNC patients by both semiconductor PET and LSO-PET. At 60 min after 18F-FDG injection, two PET scans were obtained using both scanners consecutively and in random order. Two nuclear medicine specialists scored FDG abnormalities using 5 point scale system for receiver operating characteristic (ROC) curve analysis.

Results

63 suspected of metastatic or recurrent lesions were evaluated and correlated by the final confirmation by pathological findings or clinical courses (malignant 26/benign 37). Semiconductor PET showed sensitivity of 92.3 % (24/26), specificity of 51.4 % (19/37), and accuracy of 68.2 % (43/63), while LSO-PET showed sensitivity of 84.6 % (22/26), specificity of 16.2 %(6/37), and accuracy of 44.4 % (28/63), respectively. Especially, semiconductor PET accurately diagnosed as true negative in the 13 of 14 lesions only detected by LSO-PET. ROC analyses revealed the diagnostic superiority of semiconductor PET from location of- and area under curve particularly in the study of small (≤10 mm) lesions.

Conclusion

A new novel semiconductor PET scanner can increase diagnostic accuracy with reduction in false positive findings in the HNC patients mainly due to higher spatial resolution and lower noise than the LSO-PET. This new technology can lead to more accurate diagnosis and the more optimal therapeutic tactics in head and neck surgery.  相似文献   
979.
The tight junction is not a constitutional junctional apparatus in endothelial cells, but develops in a particular lineage of endothelia, such as the capillary endothelia in the brain and retina, and thus is considered to be pivotal for the maintenance of the blood-tissue barrier. Occludin is an integral membrane component of tight junctions, but the role of occludin in the endothelial cell function remains to be elucidated. We have cloned and transfected rat full-length occludin cDNA into a rat endothelial cell line (RLE) that expressed only a trace amount of occludin with no fine circumferential actin bundles at the cell border in native conditions. Occludin was expressed at the cell border of RLE cells, and circumferential fine actin bundles developed in close relation to the sites of occludin localization. Even under subconfluent culture conditions, fine circumferential actin bundles were formed at the sites where occludin-positive cell-cell contact was achieved. In immunoelectron microscopy, occludin was localized at distinct areas of the plasma membrane, always in association with the cytoplasmic actin filaments. On the other hand, actin bundles were not seen in occludin-negative juxtaposing plasma membranes. Collectively, these data strongly suggested a possible determinant function of occludin for the organization of actin in endothelial cells.  相似文献   
980.
We report a case of postoperative recurrence of adenoid cystic carcinoma in the left parotid gland treated with radiotherapy and arterial infusion chemotherapy. A 52-year-old woman had a history of surgical resection for an adenoid cystic carcinoma arising from the left parotid gland 25 years before. Despite two reoperations for local recurrence after the initial surgery, she had a third local recurrence in the remnant of the left parotid gland. The patient was treated with a concurrent combination of radiotherapy (60 Gy/30F) and intraarterial infusion chemotherapy with carboplatin (750 mg/30 days) from which she obtained a complete response. The patient has remained free of local progression 54 months after treatment. Radiotherapy and arterial infusion chemotherapy is effective treatment for local recurrence of adenoid cystic carcinoma in the head and neck.  相似文献   
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