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81.
The aim was to develop clinical guidelines for multidetector computed tomography urography (CTU) by a group of experts from the European Society of Urogenital Radiology (ESUR). Peer-reviewed papers and reviews were systematically scrutinized. A summary document was produced and discussed at the ESUR 2006 and ECR 2007 meetings with the goal to reach consensus. True evidence-based guidelines could not be formulated, but expert guidelines on indications and CTU examination technique were produced. CTU is justified as a first-line test for patients with macroscopic haematuria, at high-risk for urothelial cancer. Otherwise, CTU may be used as a problem-solving examination. A differential approach using a one-, two- or three-phase protocol is proposed, whereby the clinical indication and the patient population will determine which CTU protocol is employed. Either a combined nephrographic-excretory phase following a split-bolus intravenous injection of contrast medium, or separate nephrographic and excretory phases following a single-bolus injection can be used. Lower dose (CTDIvol 5–6 mGy) is used for benign conditions and normal dose (CTDIvol 9–12 mGy) for potential malignant disease. A low-dose (CTDIvol 2–3 mGy) unenhanced series can be added on indication. The expert-based CTU guidelines provide recommendations to optimize techniques and to unify the radiologist’s approach to CTU. Electronic Supplementary Material The online version of this article (doi:) contains supplementary material, which is available to authorized users. ESUR:  相似文献   
82.
Background/Purpose Intraductal papillary-mucinous neoplasms (IPMNs) of the pancreas have a favorable prognosis. However, invasive ductal carcinomas of the pancreas show a rapid progression. The aim of this study was to investigate gene mutations in pure pancreatic juice from IPMN patients and to define these genetic mutations in relation to the histopathological and clinical features of IPMNs. Methods Twenty-two patients with IPMN, 21 patients with ductal carcinoma, and 20 patients with normal pancreas or chronic pancreatitis were recruited for this study. We measured the main pancreatic duct’s largest diameter and the maximum size of a dilated branch was assessed by ultrasonography or endoscopic ultrasonography. Pure pancreatic juice was collected and was investigated for K-ras, p16, and p53 mutations. Results Mutant K-ras gene was detected in 13 of the 22 patients (59.1%) with IPMNs. Different kinds of mutations were detected in the same patient in 4 cases. In the 13 patients with mutant K-ras gene, the diameter of the most dilated part of the main pancreatic duct was 2–8 mm (average, 4.5 mm) and in 7 patients with wild-type K-ras gene, the diameter was 2–5 mm (average, 2.7 mm). There was a significant difference in the diameter of the main pancreatic duct between patients with and without the mutant K-ras gene (P = 0.0323). Conclusions The incidence of K-ras mutation may be associated with the hypersecretion of mucin.  相似文献   
83.
Pericardial rupture is a rare injury following blunt chest trauma. It is frequently fatal because of serious complications such as cardiac herniation and/or contusion. We report a case of traumatic pericardial rupture without cardiac injury, which was incidentally identified intraoperatively. A 63-year-old woman was transported to the hospital after sustaining blunt chest trauma from a motor vehicle accident. Radiographic workup demonstrated multiple fractures, pulmonary contusion, and hemopneumothorax. A chest tube was inserted, and persistent bleeding was observed. An exploratory thoracotomy was performed, and active pulmonary bleeding was controlled. Further exploration revealed major pericardial rupture without cardiac herniation or intrapericardial injury, which was repaired by a bovine pericardial patch. Her postoperative course was uneventful. It is usually difficult to make a diagnosis of pericardial rupture, and a misdiagnosis often leads to a fatal consequence. Therefore, an immediate surgical exploration is warranted if clinical and radiographic findings suggest the condition.  相似文献   
84.
Background A reliable marker of chemoradiosensitivity that would enable appropriate and individualized treatment of thoracic squamous cell esophageal cancer has long been sought. We investigated whether regenerating gene (REG) Iα is such a marker. Methods We assessed expression of REG Iα in untreated endoscopic biopsy specimens and examined the correlation between REG Iα expression and the clinical responses to definitive chemoradiotherapy and prognosis. We also examined the relationship between REG Iα expression in the resected tumor and the prognosis of patients who received esophagectomy for thoracic squamous cell esophageal cancer. Results Among the 42 patients treated with definitive chemoradiotherapy, 8 of the 23 REG I-positive patients (35%) showed complete responses to chemoradiotherapy, while only one of the 19 REG I-negative patients did so. The survival rate among the REG I-positive patients was significantly better than among the REG I-negative patients. For the 76 patients treated surgically, there was no significant difference in the survival rates among the REG I-positive and REG I-negative patients. Conclusions REG Iα expression in squamous cell esophageal carcinoma may be a reliable marker of chemoradiosensitivity. We anticipate that it will enable us to provide more appropriate and individualized treatment to patients of advanced esophageal squamous cell carcinoma.  相似文献   
85.
Tracheal chondrosarcomas are rare, with only 14 cases previously documented. We report a case of chondrosarcoma of the trachea and review other published cases. Our patient was a 34-year-old man who began to feel shortness of breath 8 months after initial hemoptysis. Transverse and coronal computed tomography demonstrated a tumor that was obstructing nearly 80% of the tracheal lumen at the thoracic inlet. A bronchoscopic biopsy specimen led to an initial diagnosis of chondroma. Five tracheal rings from the third to the seventh including the tumor were completely resected, and an end-to-end anastomosis was performed. The histological diagnosis of the surgical specimen showed it to be a chondrosarcoma. The patient was alive without recurrence at 6 years 4 months after surgery. Because recurrence after incomplete resection and malignant transformation can occur with chondromas, radical resection of the trachea is recommended for all cartilaginous tumors of the trachea.  相似文献   
86.
We report a case of double cancer of the cystic duct and gallbladder associated with low junction of the cystic duct. A 73-year-old woman was admitted to the hospital complaining of upper abdominal pain. Endoscopic retrograde cholangiography showed a stenotic lesion in the lower common bile duct and no visualization of the cystic duct or gallbladder. Enhanced computed tomography revealed a heterogeneously enhanced tumorous lesion around the lower bile duct in the pancreatic head. A diagnosis of cancer arising from the cystic duct that entered the lower part of the common hepatic duct was made by intraductal ultrasonography, which showed an intraluminal protruding lesion in the cystic duct. Isolated gallbladder cancer was also diagnosed, by abdominal computed tomography. She underwent pancreaticoduodenectomy with dissection of regional lymph nodes. Histological examination revealed moderately differentiated adenocarcinoma of the cystic duct and well-differentiated adenocarcinoma of the gallbladder. Double cancer of the cystic duct and gallbladder is extremely rare, and this case also suggests a relationship between a low junction of the cystic duct and neoplasm in the biliary tract.  相似文献   
87.
We analyzed the histological high-risk factors for recurrence of submucosal invasive carcinomas (pT1) of the colon and rectum after endoscopic therapy, examining pT1 cancers treated primarily by endoscopic resection within a 23-year period. We compared recurrent and nonrecurrent cancers, evaluating the following "highrisk factors" of the primary lesion: massive invasion, a surgical margin <2 mm but negativity for cancer in the cut end, poorly differentiated adenocarcinoma (PD) (G3), undifferentiated carcinoma (G4), and/or positive angiolymphatic invasion. The following histological factors were defined as predictive of a low risk: minimum invasion, a surgical margin >2 mm, well or moderately differentiated adenocarcinoma (G1, G2), and no evidence of angiolymphatic invasion. We analyzed the records of 37 patients with pT1 cancers, including 15 with high-risk factors who underwent subsequent resection. Local recurrence with or without liver metastases developed in 4 of these 15 patients. The histological type was PD in three (75%) of the four recurrent lesions. All four (100%) lesions showed a desmoplastic response (DR). Only 1 (9%) of the 11 patients without recurrence after subsequent surgery had a lesion with a small component of PD, and only three (27%) lesions showed a mild DR. We concluded that endoscopic therapy is inadequate for pT1 cancers with a histological PD component, and/or a DR in the cancer stroma.  相似文献   
88.
A 72-year-old woman with asymptomatic macrohematuria was referred to our hospital. Cystoscopy revealed a 7 cm sessile tumor on the left lateral wall of the bladder. Subsequently an intravenous pyelography revealed left hydronephrosis. We performed transurethral biopsy and resection of the bladder tumor under the diagnosis of ordinary malignant bladder tumor. Histopathologically, the lesion was shown to be an undiffentiated urothelial carcinoma, G3, > or = pT2, containing syncytiotrophoblastic giant cells. The level of serum human chorionic gonadotropin-beta (hCG-beta) level was slightly elevated (0.3 ng/ml; normal value: < 0.1). Because a further examination revealed an invasion into the surrounding fat tissue of the bladder and left ureter, a total cystohysterectomy with an ileal conduit were performed. The final histopathological classification was choriocarcinoma of the urinary bladder, pT3a, pN1, pMx. An adjuvant combination chemotherapy was carried out using methotrexate, vinblastine, adriamycin and cisplatin (MVAC). After two courses of chemotherapy, the serum hCG-beta levels returned to normal. Eleven months postoperatively, however, there was evidence of multiple lung metastases. The patient died 12 months after the surgery as a result of complications caused by widespread metastases.  相似文献   
89.
Background: Vascular smooth muscle tone is regulated by changes in intracellular free Ca2+ concentration ([Ca2+]i) and myofilament Ca2+ sensitivity. These cellular mechanisms could serve as targets for anesthetic agents that alter vasomotor tone. This study tested the hypothesis that propofol increases myofilament Ca2+ sensitivity in pulmonary artery smooth muscle (PASM) via the protein kinase C (PKC) signaling pathway.

Methods: Canine PASM strips were denuded of endothelium, loaded with fura-2/AM, and suspended in modified Krebs- Ringer's buffer at 37[degrees]C for simultaneous measurement of isometric tension and [Ca2+]i.

Results: The KCl (30 mm) induced monotonic increases in [Ca2+]i and tension. Verapamil, an L-type Ca2+ channel blocker, attenuated KCl-induced increases in [Ca2+]i and tension to an equal extent. In contrast, propofol attenuated KCl-induced increases in [Ca2+]i to a greater extent than concomitant changes in tension and caused an upward shift in the peak tension-[Ca2+]i relation. Increasing extracellular Ca2+ in the presence of 30 mm KCl resulted in similar increases in [Ca2+]i in control and propofol-pretreated strips, whereas concomitant increases in tension were greater during propofol administration. The Ca2+ ionophore, ionomycin (0.1 [mu]m), increased [Ca2+]i to approximately 50% of the value induced by 60 mm KCl. Under these conditions, propofol (10, 100 [mu]m) caused increases in tension equivalent to 11 +/- 2 and 28 +/- 3% of the increases in tension in response to 60 mm KCl, whereas [Ca2+]i was slightly decreased. Similar effects were observed in response to the PKC activator, phorbol 12-myristate 13-acetate (PMA, 1 [mu]m). Specific inhibition of PKC with bisindolylmaleimide I before ionomycin administration decreased the propofol- and PMA-induced increases in tension and abolished the propofol- and PMA-induced decreases in [Ca2+]i. Selective inhibition of Ca2+-dependent PKC isoforms with Go 6976 also attenuated propofol-induced increases in tension.  相似文献   

90.
In contrast to malignant lymphomas or skin cancer, smooth muscle tumors including leiomyosarcoma are rarely associated with transplant recipients. We herein present a 33-year-old woman with end-stage renal disease who received a transplant at 27 years of age. Four years after the transplantation, at age 31, she underwent a mastectomy because of primary right breast cancer, which was found to be a 5-mm-sized mucinous carcinoma with no regional lymph node metastasis. Six years after the transplantation, a liver tumor was unexpectedly discovered. An explorative laparotomy revealed a well-encapsulated tumor occupying the posterior portion of the right lobe of the liver. The patient underwent a posterior segmentectomy. Histologically, the tumor possessed intermingling fascicles of spindle cells with eosinophilic cytoplasm and elongated nuclei. Based on an immunohistochemical examination, the tumor cells were positive for the muscle-associated antibody. In addition, RNA probes for Epstein-Barr virus were negative based on in situ hybridization. The histologic, immunohistochemical findings were considered to be diagnostic for leiomyosarcoma, which is a low-grade malignancy. Two years after surgery, the patient is doing well with no recurrence of liver tumors or breast cancer. Received: April 16, 2001 / Accepted: September 11, 2001  相似文献   
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