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We have measured the direct effects of propofol 10–7-10–4mol litre–1 on isolated canine cerebral, coronary, mesenteric,femoral and renal arteries. In arterial strips precontractedsubmaximally with potassium chloride or prostaglandin F2  相似文献   
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A high-performance liquid chromatographic (HPLC) assay was developed for the determination of trazodone and its metabolite, 1-m-chlorophenylpiperazine (m-CPP), in plasma. The high level of trazodone in plasma was detected by ultraviolet absorbance at 254 nm and the low level of m-CPP in plasma was detected by coulometric electrochemical detection at 840 mV on the series arrangement of two detectors. Pilsicainide as an internal standard for both compounds was monitored by both detectors. Trazodone and m-CPP in plasma were extracted by a rapid and simple procedure based on CN bonded-phase extraction, and C8 reversed-phase HPLC separation. Determination was possible for trazodone in the concentration range 100–2000 ng mL?1 and for m-CPP in the concentration range 5–100 ng mL?1. The recoveries of trazodone and m-CPP added to plasma were 81·0–84·2 and 68·0–73·2%, respectively, with coefficients of variation of less than 7·3 and 8·2%, respectively. The method is applicable to high level monitoring of trazodone and low level monitoring of m-CPP in plasma of healthy volunteers and patients treated with trazodone.  相似文献   
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Diagnosis of Small Pancreatic Carcinoma   总被引:1,自引:0,他引:1  
A retrospective analysis was performed to evaluate the clinicalsymptoms and abnormal test findings in small pancreatic carcinoma.Five hundred and thirty-six cases of pancreatic carcinoma withthe histology of duct cell carcinoma were collected from 14medical centers in Japan. In 440 of the cases, tumor size wasmeasured at the time of laparotomy or from the resected specimen.Three hundred and seventy-seven patients (86%) had a carcinomalarger than 3.0 cm; only 30% of these were resectable. Sixty-threepatients (14%) had a carcinoma of 3.0 cm or less, with resectabilityof 97%. Detecting a tumor of "3 cm or less" with a high probabilityof resectability is the objective of early diagnosis with theresulting possibility of a cure. In most cases these small carcinomaswere found easily when obstructive jaundice was present (73%).However, the estimated occurrence of obstructive jaundice associatedwith carcinomas of 3 cm or less was only 10% among the totalcases of pancreatic carcinoma studied. Therefore, it is necessaryfor early diagnosis to detect carcinomas of 3 cm or less presentingwithout jaundice. The symptoms of small carcinoma without jaundiceare weight loss, anorexia, upper abdominal pain, back pain anda palpable abdominal mass. Among the various available examinations,endoscopic retrograde cholangiopancreatography, computerizedtomography and ultrasonography were valuable in diagnosing thesesmall carcinomas.  相似文献   
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Eosinophils are characterized by several functional properties, such as chemotaxis, adhesion, superoxide anion production, and degranulation. In this article, we have studied the role of bacterial ingestion by eosinophils in comparison with that by neutrophils. Eosinophils and neutrophils were purified by using the Percoll gradient method followed by selection with CD16‐coated immunomagnetic beads and centrifugation through a Ficoll‐Hypaque gradient combined with dextran sedimentation, respectively. Both cells were preincubated with anti‐FcγRIIa mAb (CD32 mAb), anti‐FcγRIIIb mAb (CD16 mAb), anti‐CR3 (CD11b mAb), or anti‐CR1 (CD35 mAb) before being examined for phagocytosis of opsonized heat‐killed Staphylococcus aureus (S. aureus). Phagocytosis and production of hydrogen peroxide were simultaneously measured by flow cytometry using S. aureus labeled with propidium iodide and stained with 2′,7′‐dichlorofluorescein diacetate. Eosinophils showed significantly lower activity than neutrophils in both phagocytosis and hydrogen peroxide production. Phagocytosis by both cells was decreased by heat‐inactivated serum. Phagocytosis by neutrophils was significantly inhibited by CD16 mAb and CD32 mAb, whereas that by eosinophils was only inhibited by CD35 mAb. Whereas the mechanism of phagocytosis by neutrophils was mediated by CD16 and CD32, that of eosinophils was modulated by complement receptor 1 (CD35).  相似文献   
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Portal-hypertensive gastropathy   总被引:3,自引:0,他引:3  
In the present article we describe updated information concerning the clinical feature of portal-hypertensive gastropathy (PHG), which is characterized by mucosal and submucosal vascular dilatation without inflammation. Although this lesion represents non-variceal bleeding, there is a wide variation of its prevalence. Portal pressure and some humoral factors may play important roles in its pathogenesis. Gastric acid secretory activity is reduced, whereas the gastric mucosal barrier is impaired. With regard to gastric mucosal haemodynamics, whether ‘overflow’ (i.e. active congestion) or ‘stasis’ (i.e. passive congestion) cause gastric mucosal hyperaemia is not known. A severe lesion is a potential source of bleeding, while mild lesions are of little clinical significance and endoscopic variceal obliteration aggravates PHG in some patients. In the treatment of PHG, pharmacological (e.g. propranolol), surgical (e.g. portosystemic shunt) and radiological (e.g. transjugular intrahepatic portosystemic shunt) procedures may be useful in preventing bleeding from PHG.  相似文献   
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The epithelial expression of apomucins MUC1, MUC2, MUC3, and MUC5/6 was examined in normal pancreas and in pancreatic lesions, using immunohistochemical methods. In normal pancreas ( n =5), MUC1 apomucin was expressed in ducts and some acini, but there was no expression of MUC2, MUC3, or MUC5/6. In chronic pancreatitis ( n =5), MUC1 apomucin was expressed, but expression of the other apomucins was not noted. However, mucous hyperplastic foci of pancreatic ducts expressed MUC5/6 apomucin in 2/5 cases (40 per cent). In intraductal papillary-mucinous neoplasm (IPMN) of the pancreas ( n =9), MUC1, MUC2, MUC3, and MUC5/6 apomucins were expressed in 8/9 (89 per cent), 0/9 (0 per cent), 4/9 (44 per cent), and 9/9 (100 per cent) cases, respectively. In pancreatic mucinous cystadenoma ( n =8), MUC1, MUC2, MUC3, and MUC5/6 apomucins were expressed in 7/8 (88 per cent), 0/8 (0 per cent), (25 per cent), and 3/8 (38 per cent) cases, respectively. In invasive ductal adenocarcinoma of the pancreas ( n =25), expression of MUC1, MUC2, MUC3, and MUC5/6 apomucins was found in 25/25 (100 per cent), 1/25 (4 per cent), 20/25 (80 per cent), and 24/25 (96 per cent) cases, respectively. Atypical mucous duct hyperplasia near cancer cells consistently expressed MUC1 apomucin and occasionally expressed MUC3 and MUC5/6. In positive cases, MUC1 apomucin expression was noted in the cell membrane facing the ductal or neoplastic lumina, while expression of MUC2, MUC3, and MUC5/6 apomucins was found in the cytoplasm. These results suggest that MUC3 and MUC5/6 apomucins newly emerge during the neoplastic transformation of pancreatic mucinous cystadenoma and IPMN and during pancreatic ductal carcinogenesis, while MUC1 apomucin remains positive and MUC2 apomucin remains almost negative during neoplastic transformation.  相似文献   
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