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91.
The mechanism by which prostacyclin acts to prevent in vivo reperfusion injury is still uncertain. This study was therefore undertaken to assess the effect of a stable prostacyclin analogue (OP 41483-alpha-CD [OP]) on oxygen-derived free radicals after heart-lung transplantation. OP was administered to the heart-lung graft through the pulmonary artery for 25 minutes encompassing the reperfusion process. Free radicals were directly measured by electron spin resonance spectroscopy. The radical intensities of pulmonary venous blood were significantly lower in the OP group than in the control group, suggesting that fewer free radicals were generated in the lungs of the OP group. The cardiac and respiratory function were better in the OP group than in the control group. The lung is the primary source of oxygen free radical attack, and the beneficial action of OP on free radical generation is almost exclusively restricted to the lung and does not apply to the heart. This result suggested that OP probably is effective in inhibiting free radical generation from the endothelium.  相似文献   
92.
Determining the site and severity of blood loss is important in the management of children with gastrointestinal (GI) bleeding. Blood urea nitrogen (BUN) and serum creatinine (Cr) were measured on the day of hospitalization and the ratio of BUN/Cr was calculated in 11 children with 16 episodes of upper GI bleeding and 49 with lower GI bleeding. There was a significant difference between the two GI bleeding groups with regard to BUN/Cr ratio (p less than 0.001). When the ratio was 30 or above, the specificity of upper GI bleeding was 98% with a sensitivity of 68.8%. A linear relationship was found between the BUN/Cr ratio and delta Hb (delta Hb = 0.08 x BUN/Cr +/- 0.8 g/dl) for bleeding originating from the upper GI tract. This study confirms that measurement of the BUN/Cr ratio is useful for localizing the source of bleeding to the upper GI tract and also demonstrates its usefulness as an estimation of the severity of blood loss from the upper GI tract.  相似文献   
93.
94.
A 23-year-old woman had lower abdominal pain, diarrhea and bloody stool was admitted and given a diagnosis of influenza B. Her home doctor had started treatment by neuraminidase inhibitor (oseltamivir) the previous day. Colonoscopic examination revealed an area of hemorrhage and erosion in the left transverse colon. After halting oseltamivir treatment these symptoms disappeared and her colonoscopic findings improved. A drug-induced lymphocyte stimulation test was positive for oseltamivir. This case is the first reported case of acute hemorrhagic colitis induced by oseltamivir.  相似文献   
95.
Aortic allograft valves were harvested from non-infected (bacterial or viral) cadavers within 24 hours of death with a family consent, and were sterilized by 4 degrees C antibiotic solution for 48 hours. Then, the allograft was preserved in the 4 degrees C nutrient medium (fresh; TC-199, calf serum and HEPES buffer) or in liquid nitrogen (-196 degrees C) after freezing to -80 degrees C by a programmed freezer. 10% dimethylsulfoxide (DMSO) was used for cryopreservation. Following germ-free confirmation, aortic allograft valves were implanted in 5 patients having aortic regurgitation with good results. Three fresh and two cryopreserved allograft valves were used. Although the follow-up term is very short (maximum 1 year) at the present time, the valve function is quite satisfactory, confirmed by cardiac catheterization and echocardiography. This is the first report in Japan with regard to cryopreservation of allograft valves and clinical use of fresh or cryopreserved valves. We believe that realization and progress of allograft preservation by cryo-technique and establishment of the tissue bank are important for the development of cardiovascular surgery in Japan.  相似文献   
96.
97.
To evaluate prognostic significance of echogenic lesion within small hepatocellular carcinoma (SHCC, less than or equal to 2 cm in diameter), clinical and pathological findings of 32 cases with SHCC containing echogenic lesion (echogenic SHCC) were compared with those of 55 cases with non-echogenic SHCC. Compared with the non-echogenic SHCC group, the frequency of clinical stage I was significantly higher, and there were significantly more cases with solitary tumor relative to cases with multiple tumors in the echogenic SHCC group. Histologically, the incidence of the HCC composed of well-differentiated tumor cells corresponding to Edmondson's grade I was significantly higher in the echogenic SHCC group than in the non-echogenic SHCC group. Although HCCs tended to become progressively less differentiated with increasing tumor sizes in the both groups, the process of cellular change appeared to proceed more slowly in the echogenic SHCC group. Survival rate after tumor detection was 73% at three years, 56% at five years and 48% at seven years and nine years in the echogenic SHCC group, while it was 46% at three years, 42% at five years and 0% at seven years in the non-echogenic SHCC group. The present results showed that the presence of echogenic lesion within SHCC could be useful prognostic indicator.  相似文献   
98.
Lipoprotein is known to increase during pregnancy but the factors responsible for the change have not been established. In addition, the lipoprotein concentration in preeclamptic pregnancy is significantly higher than in normal pregnancy. The apolipoproteins are an important determinant of metabolism and the structure of plasma lipoproteins. In normal pregnancies, non pregnancies and preeclamptic pregnancies the levels of blood apolipoproteins AI, AII, B and E were determined by TIA methods. (1) In normal pregnancies, the concentrations of apolipoproteins AI, AII, B and E were 182.6 +/- 20.9 mg/dl (n = 12, mean +/- S.D.), 33.3 +/- 5.7 mg/dl, 128.6 +/- 20.8 mg/dl, and 6.8 +/- 1.9 mg/dl, respectively. (2) In the pregnancies, the concentrations of apolipoproteins AI, AII, B and E were 135.6 +/- 9.3 mg/dl (n = 5), 30.8 +/- 1.9 mg/dl, 76.0 +/- 19.7 mg/dl, and 4.4 +/- 0.7 mg/dl, respectively. (3) In the preeclamptic pregnancy, the concentrations of apolipoproteins AI, AII, B and E were 181.0 +/- 27.6 mg/dl (n = 22), 33.2 +/- 4.8 mg/dl, 145.7 +/- 41.6 mg/dl and 5.8 +/- 1.4 mg/dl, respectively. The concentration of apolipoprotein B in preeclamptic pregnancy was significantly higher (p less than 0.001) and apolipoprotein E was significantly lower (p less than 0.01) than in normal pregnancies. These data suggest that the measurement of apolipoprotein is useful for the evaluation of preeclamptic pregnancy.  相似文献   
99.
100.
We measured plasma heparin cofactor II (HC II) activity in patients with disseminated intravascular coagulation (DIC) due to various underlying diseases together with the levels of antithrombin III (AT III), pseudocholinesterase (a marker of hepatic synthesis), and various haemostatic molecular markers. Both HC II and AT III were decreased in DIC secondary to all the underlying diseases studied, except acute promyelocytic leukemia (APL), when compared with healthy subjects. The lowest HC II and AT III levels was observed in coagulopathy secondary to liver disease, the HC II level in sepsis was the second lowest. In DIC due to APL, the decrease in HC II was not accompanied by a decrease in AT III. Thus, we divided all 124 samples tested into APL and non-APL groups. The HC II level correlated positively with fibrinogen and plasminogen in both the APL and non-APL groups. In the APL group, the HC II level had a significant negative correlation with the thrombin-AT III complex (TAT), fibrinogen/fibrin degradation products, and D-dimer levels as well as the prothrombin time, while AT III showed no correlations with any of the haemostatic parameters. These results suggest that HC II may be consumed preferentially by thrombin in APL patients with DIC, and thus may spare the consumption of AT III. Accordingly, HC II seems to be a superior indicator of DIC than AT III in APL patients. Moreover, replacement therapy with HC II instead of AT III may be useful to treat DIC associated with APL. In the non-APL group, the HC II levels were positively correlated with the levels of AT III and pseudocholinesterase activity. This indicates that plasma HC II levels are closely related not only to consumption coagulopathy but also to hepatic synthetic activity, as is the case for plasma AT III.  相似文献   
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