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101.
Lack of rapid initiating, promoting or sequential syncarcinogenic effects of di(2-ethylhexyl)phthalate in rat liver carcinogenesis 总被引:2,自引:0,他引:2
The effect of prolonged dietary administration of the peroxisomeproliferating plasticizer di(2-ethylhexy1)phthalate (DEHP wasstudied on liver carcinogenesis initiated by N-2- fltuorenylmxhmide(FAA) and with that of the neoplasm-promoter phenobarbital (PB).Also, DEHP was studied as an initiator by giving it in placeof FAA before PB. Male rats were fed FAA for 7 weeks to inducebepatocellular altered foci, and were subsequently given nochemical, 12 000 p.p.m. DEHP or 500 p.p.m. PB for 24 weeks inthe diet. In the rats fed DEHP, substantial hepatomegaly andperoxisome proliferation were induced. No evidence of indudionof hepatacellular altered foci or hepatic neoplasms was foundeither when DEHP was given alone for 24 weeks or for 7 weeksfollowed by PB. Also, DEHP fed for 24 weeks had no promotingeffect on liver altered foci that were induced by FAA and producedlittle or no enhancement of the occurrence of FAA-induced liverneoplasms. In contrast, PB exerted a marked enhancing effecton foci and substantially increased the incidence and multiplicityof liver neoplasms. Thus, the findings demonstrate that DEHPdid not have either a rapid initiating activity, a significantsequential syncarcinogenic activity, or a promoting effect onliver carcinogenesis under conditions in which numerous agentswith such activities have been identified. 相似文献
102.
Invasion of the skull base by carcinomas: histopathologically evidenced findings with CT and MRI 总被引:3,自引:0,他引:3
Haruhiko Ishida Mitsuhiro Mohri Mutsuo Amatsu 《European archives of oto-rhino-laryngology》2002,259(10):535-539
The depth and extent of the invasion of the skull base by a tumor are the most critical information for successful en bloc resection of the tumor. The only means available for the evaluation of these factors are CT or MRI images. In order to clarify the ability of these imaging modes to delineate the invasion of the skull base, preoperative images of ten patients who underwent en bloc resection of skull base tumors at Kobe University Hospital were compared with the histopathological findings of the resected specimens. CT proved to be superior to MRI for evaluating bone destruction of the skull base. On the other hand, MRI provided more useful information about intracranial invasion than CT. As a hypertrophic linear shadow on Gd-enhanced MRI represented dural invasion or thickened dura mater adjacent to the tumor, this technique should be taken into consideration to determine the dural resection. We concluded that preoperative evaluation of the depth of skull base invasion by both CT and Gd-enhanced MRI is essential for planning complete tumor resection. 相似文献
103.
The preoperative diagnosis of diffuse heterotopic submucosal cystic malformation of the stomach is very difficult to make with upper gastrointestinal (GI) series or endoscopy. We report a case of submucosal cysts associated with an early gastric carcinoma in which ultrasonography (US) and endoscopic ultrasonography (EUS) were very useful in the preoperative diagnosis. 相似文献
104.
Electrochemotherapy is a novel antitumor treatment involving the systemic administration of bleomycin followed by the delivery
of electrical pulses to the tumor. The present study investigates the effects of electrochemotherapy on the growth of colon
26 cells inoculated subcutaneously into the backs of BALB/c mice. The mice were divided into the following four experimental
groups: 20 that received no further treatment after the inoculation of colon 26 cells (control group); 20 that received 500
μg of bleomycin intraperitoneally 7 and 9 days after the inoculation (BLM group); 20 that received electric pulses to the
tumor 7 and 9 days after the inoculation (EP group); and 30 that received electrochemotherapy 7 and 9 days after the inoculation
(ECT group). During 28 days of observation, no deaths due to tumor progression occurred in the ECT group, but there were 18
in the control group, 11 in the BLM group, and 18 in the EP group. While weight loss was observed in all groups, it was most
remarkable in the control group. Tumor growth was significantly inhibited in the ECT group, compared to the other experimental
groups (P<0.01). The results of this study demonstrated that electrochemotherapy significantly inhibited the growth of colon 26 tumors
in mice, without causing any remarkable adverse effects. 相似文献
105.
Minoru Yagi Takeshi Mishina Tsukasa Fujishima Kazutoshi Date Hiroshi Saito Nobuo Suzuki 《Surgery today》1997,27(1):84-87
The acute onset of peritoneal signs and shock in a 7year-old boy who had been hit in the epigastrium by a log-seesaw mandated surgical treatment. Enhanced computed tomography (CT) demonstrated complete laceration of the pancreas as well as duodenal injury, and a duodenoduodenostomy with distal pancreaticogastrostomy was subsequently performed. Temporary external drainage of the stomach and distal pancreas led to an uneventful recovery in the early postoperative period. Although the patient's postoperative development was appropriate for his age, the orifice of the distal pancreas spontaneously closed 2.5 years following surgery. We present this report to stress the fact that every effort should be made to preserve the pancreas following abdominal injury in children. 相似文献
106.
S Yoshii T Fuzii T Saitoh R Yamamoto N Ishida Y Hosoi M Tahara 《Nihon Hinyōkika Gakkai zasshi. The japanese journal of urology》1992,83(3):374-382
Thirty-five patients with benign prostatic hyperplasia (age range: 45-88 years; average: 67.5 years) underwent local thermotherapy with prostathermer. Clinical therapeutic effect was evaluated in 30 of the 35 patients: 2 patients interrupting from therapy and 3 receiving pretherapeutic indwelling catheters were not included. A total of 6 treatments (2 per week) were performed, each lasting for 60 minutes. As for subjective improvement, improvement of nocturia was noted in 70.0% of all patients and sense of residual urine in 70.7%. Post-therapeutic nocturnal and daytime decreases in urination frequency were statistically significant (p less than 0.01). Objective improvement in residual urine volume occurred in 19 of the 30 cases, and elevation in uroflowmetric maximal flow rate following therapy was statistically significant (p less than 0.05). Among complications ascribable to catheter insertion were urethral bleeding (3 cases), epididymitis (1 case) and pyuria (1 case). Therapeutic result based primarily on subjective symptoms and partly on objective findings was fairly good in 17 cases (about 57%), and slightly good in 25 cases (about 83%). In conclusion, this therapy seems to be useful in the treatment of benign prostatic hyperplasia. 相似文献
107.
Atsushi Ota Nobuyasu Kano Hiroshi Kusanagi Shigetoshi Yamada Arty Garg 《Journal of hepato-biliary-pancreatic sciences》2003,10(2):172-175
Our basic techniques for the management of difficult cases of laparoscopic cholecystectomy (LC) are presented in this article. If access to Calot's triangle cannot be gained safely, dissection should be started at the fundus or body of the gallbladder (GB), rather than the neck (fundus-first method). In cases with a short and wide cystic duct, a transfixing suture should be applied for ligation instead of clipping. EndoGIA is useful for ligating and transecting this case to avoid a subsequent stricture caused by normal method of ligation. Intraoperative cholangiography should be performed near the neck of the GB in cases in which orientation is lost during dissection. More dissection should be performed in the direction of the junction of the bile ducts after orientation is regained. In cases with GB filled with stones accompanied by severe fibrosis, part of the GB is incised to remove the stones and expose the lumen of the GB. Confluence stones can be removed by placing an incision on the GB side of the junction of the duct. The incised part is closed with suture. A cystic tube (C-tube) is placed in the common bile duct through the cystic duct for decompression. In more difficult cases in which dissection cannot be started safely at any location, the body and the fundus of the GB are excised, and a drain is placed at the neck of the GB. Dissection can be carried out from the main surgeon's or the assistant's side depending on the situation, and cooperation between the two surgeons is mandatory to achieve safe LC in difficult cases. When performing the LC, one must have a low threshold for converting to open surgery if injuries cannot be managed safely. 相似文献
108.
Koichiroh Nandate Kenji Muranaka Koichi Shinohara Kazuyoshi Ishida Hiroko Ishida Katsuhiro Seo Hiroshi Takeshita 《Journal of anesthesia》1997,11(2):117-120
We retrospectively reviewed the records of 250 consecutive patients undergoing coronary artery bypass graft surgery (CABG)
from January 1994 through January 1996 to determine the incidence of persistent postoperative neurological dysfunction after
CABG and to compare normothermic and moderate hypothermic cardiopulmonary bypass (CPB). Normothermic CPB was used in 128 patients
(36°–37°C) and hypothermic CPB (27°–28°C) in 122 patients. Postoperative neurological dysfunction included focal motor deficits,
delayed recovery of consciousness (>24h) after surgery, and seizures within 1 week postoperatively. Persistent neurological
dysfunction was diagnosed if complete resolution had not occurred within 10 days of surgery. The incidence of persistent postoperative
neurological dysfunction was 4.1% in the hypothermic CPB group and 2.3% in the normothermic CPB group. There were no statistically
significant differences between the two groups (P=NS). These results suggest that normothermic CPB did not increase the incidence of persistent postoperative neurological
dysfunction compared to hypothermic CPB. 相似文献
109.
Masayoshi Hamawaki Motoharu Narimatsu Hiroshi Yamaguchi Katsuo Nishi Kiyoyuki Eishi 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2003,51(3):110-112
A 10-year-old girl having bilateral subclavian steal associated with severe coarctation of the thoracic aorta and an aberrant
right subclavian artery was found, on admission, to have no difference between upper and lower extremity blood pressure, but
echocardiography revealed severe thoracic aorta coarctation and systolic blood pressure in the carotid arteries exceeding
200 mmHg estimated by Doppler ultrasonography. Magnetic resonance imaging and angiography demonstrated bilateral subclavian
steal without esophageal compression. We reconstructed the aortic arch using the left subclavian artery and a reversed Blalock-Park
procedure, then repaired the coarctation with a 14 mm woven double velor vascular graft. The girl was symptom-free following
uncomplicated recovery from surgery. Doppler ultrasonography 2 weeks after surgery showed the pressure gradient across the
aortic arch had decreased from 180 mmHg to 60 mmHg. This residual gradient at the anastomosis between the ascending aorta
and left subclavian artery may improve as native vessels grow. 相似文献
110.
Daisuke Morioka Mureo Kasahara Yasutsugu Takada Yasumasa Shirouzu Kaoru Taira Seisuke Sakamoto Kenji Uryuhara Hiroto Egawa Hiroshi Shimada Koichi Tanaka 《Liver transplantation》2005,11(11):1332-1342
To address the current role of liver transplantation (LT) for urea cycle disorders (UCDs), we reviewed the worldwide English literature on the outcomes of LT for UCD as well as 13 of our own cases of living donor liver transplantation (LDLT) for UCD. The total number of cases was 51, including our 13 cases. The overall cumulative patient survival rate is presumed to be more than 90% at 5 years. Most of the surviving patients under consideration are currently doing well with satisfactory quality of life. One advantage of LDLT over deceased donor liver transplantation (DDLT) is the opportunity to schedule surgery, which beneficially affects neurological consequences. Auxiliary partial orthotopic liver transplantation (APOLT) is no longer considered significant for the establishment of gene therapies or hepatocyte transplantation but plays a significant role in improving living liver donor safety; this is achieved by reducing the extent of the hepatectomy, which avoids right liver donation. Employing heterozygous carriers of the UCDs as donors in LDLT was generally acceptable. However, male hemizygotes with ornithine transcarbamylase deficiency (OTCD) must be excluded from donor candidacy because of the potential risk of sudden-onset fatal hyperammonemia. Given this possibility as well as the necessity of identifying heterozygotes for other disorders, enzymatic and/or genetic assays of the liver tissues in cases of UCDs are essential to elucidate the impact of using heterozygous carrier donors on the risk or safety of LDLT donor-recipient pairs. In conclusion, LT should be considered to be the definitive treatment for UCDs at this stage, although some issues remain unresolved. 相似文献