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71.
BACKGROUND: The development of well-matured fibrosis in usual interstitial pneumonia (UIP) is strongly associated with an unfavorable outcome of patients with idiopathic pulmonary fibrosis (IPF). However, differences in the rates of development are likely to result in variable clinical courses in IPF patients. OBJECTIVE: We tried to evaluate the progression of honeycombing and ground-glass opacity on CT using a scoring system, and to examine those serial changes in the clinical course of disease. METHODS: A hospital-based, retrospective cohort study. Twenty-three patients with IPF diagnosed as UIP by surgical lung biopsy were analyzed during the initial examination by scoring the presence of honeycombing (HC: range, 0-24) and ground-glass opacity (GG: range, 0-24) on CT scan. We also compared the serial changes observed in the CT scores (interval: 2-42 months, 2-6 examinations). RESULTS: (1) The serial change in the HC score in treated patients (n = 10) was similar to that in untreated patients (n = 16); (2) the HC score at the time of the initial examination and the rate of HC progression were both higher in the non-surviving patients (HC 12.3 +/- 3.7, mean +/- SD; deltaHC 4.2 +/- 1.3 per year) than in the surviving patients (HC 5.8 +/- 2.7; deltaHC 1.2 +/- 0.7 per year) (p < 0.05); (3) the GG score did not correlate with the HC score at any of the examinations; (4) the HC score was higher in the lower lung field than in the upper and middle lung fields. CONCLUSIONS: Scoring of the honeycombing and its serial changes using the high-resolution computed tomography scoring method was useful for predicting the prognosis in patients with IPF/UIP. Corticosteroid treatment did not prevent the progression of HC.  相似文献   
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Relationship between neutrophil elastase and acute lung injury in humans   总被引:16,自引:0,他引:16  
We conducted clinical trials in patients with acute lung injury (ALI) associated with systemic inflammatory response syndrome using a selective neutrophil elastase inhibitor, sivelestat sodium hydrate (Sivelestat), to investigate the involvement of neutrophil elastase in ALI. In the phase III double-blind study (Study 1) in 230 patients, the efficacy of Sivelestat was evaluated with the pulmonary function improvement (PFI) rating as the primary endpoint, and the weaning rate from mechanical ventilator, the discharge rate from intensive care unit (ICU), and the survival rate as secondary endpoints. Afterwards, an unblinded study (Study 2) in 20 patients was conducted using procedures for weaning from mechanical ventilation to reevaluate its efficacy with ventilator-free days (VFD) value, the primary endpoint, and to compare with that of Study 1 subgroup, which met the selection criteria used in Study 2. Sivelestat increased PFI rating, reduced duration of mechanical ventilation, and shortened stay in ICU in Study 1, although there was no significant efficacy on the survival rate. VFD value in Study 2 was comparable to that in the optimal-dose group of Study 1 subgroup, and increase in VFD value correlated with PFI rating and increase in ICU free days. It was concluded that neutrophil elastase may be involved in the pathogenesis of ALI in humans.  相似文献   
75.
We report the presence of a patent ductusvenosus in three brothers who underwent surgicalcorrection. Patent ductus venosus was demonstrated byultrasonography. Portosystemic venous shunt ratios asevaluated by [123I]iodoamphetamine per rectalportal scintigraphy were 67%, 50%, and 77%,respectively. Histologic examination of liver biopsyspecimens revealed fatty degeneration in all cases.Portal vein pressure before and after temporarily occluding thepatent ductus venosus was estimated by an Anthron P-Ucatheter introduced into the portal vein via theligament teres hepatis. Portal venous pressure increased from 10 to 17 cm H2O, 16 to 23 cmH2O, and 14 to 27 cm H2O,respectively. Therefore, banding of the ductus venosuswith Teflon tape was attempted to prevent portalhypertension following complete ligation. As a result, portal venous pressures afterstricture of the ductus venosus were 12, 21, and 20 cmH2), respectively. Bile acid and liver enzymes decreasedand returned to normal within 14 days after surgery. Interestingly, serum concentrations ofhepatocyte growth factor (HGF) increased significantlyafter restoration of the portal blood flow and thengradually decreased, but remained persistently elevated for at least two weeks in two cases measuredafter surgical correction. One month after correction,liver function returned to normal as assessed byserological and histological parameters in all cases. These results suggest that it is important todetermine whether stricture or complete ligation isindicated for a patent ductus venosus during surgicalcorrection, based on the portal venous pressure after temporal test occlusion of the duct. Inaddition, HGF may be a useful marker for normalizationof hepatic microcirculation after surgery.  相似文献   
76.
BACKGROUND AND AIM: Balloon-occluded retrograde transvenous obliteration (B-RTO) is a novel therapeutic method for the treatment of large gastric fundal varices with spontaneous splenorenal shunt (SRS). However, the effects of B-RTO on liver function remain unknown. METHODS: Fourteen patients with portal hypertension and gastric varices with SRS were studied, consisting of four patients with acute bleeding, five with high-risk varices, and five with refractory portosystemic encephalopathy. Hepatic venous catheterization was performed to evaluate hepatic blood flow and liver function using the continuous indocyanine green (ICG) infusion method. To assess the metabolic activity of the hepatocyte, the intrinsic clearance of ICG was calculated. In all patients, endoscopic study was performed before and 1 week and 1 month after the B-RTO, and followed every 6 months thereafter. After baseline measurements, B-RTO was performed. Four weeks after the B-RTO, the same catheter measurements were repeated. RESULTS: The B-RTO was successful in all patients. Contrast-enhanced computed tomography showed complete obliteration of the SRS prior to the follow-up measurements. Endoscopic eradication of the fundal varices was obtained 6 months after B-RTO in all patients and encephalopathy was improved within 1 week after B-RTO. Following the B-RTO, hepatic blood flow (441 +/- 214 vs 668 +/- 299 mL/min, P < 0.0001) and the intrinsic clearance of ICG (233 +/- 123 vs 285 +/- 148 mL/min, P < 0.05) were significantly increased. Furthermore, intrahepatic resistance decreased after the B-RTO (P < 0.005). CONCLUSION: From short-term assessment, B-RTO increases hepatic blood flow and improves the metabolic activity of the liver in patients with portal hypertension.  相似文献   
77.
Understanding what maintains species and perpetuates their coexistence in a network of feeding relationships (the food web) is of great importance for biodiversity conservation. A food web can be viewed as consisting of a number of simple subunits called trophic modules. Intraguild predation (IGP), in which a prey and its predator compete for the same resource, is one of the best-studied trophic modules. According to theory, there are two ways to yield a large persistent system from such modules: (i) to use persistent subunits as building blocks or (ii) to arrange the subunits in a way that externally supports the nonpersistent subunits. Here, I show that the complex food web of the Caribbean marine ecosystem is constructed in both ways. I show that IGP modules, which convey internal persistence because of the fact that prey are superior competitors for the resources, are overrepresented in the Caribbean ecosystem. The other modules, consisting of competitively inferior prey, are not persistent in isolation. However, competitively inferior prey in these modules tend to receive more advantage from extra-module interactions, which allows persistence of the IGP module. In addition, those exterior interactions tend to be provided by intrinsically persistent IGP modules to prevent cascading extinction of interacting IGP modules. The food web can be viewed as a set of interacting modules, nonrandomly arranged to enhance the maintenance of biodiversity.  相似文献   
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A 63-year-old male was admitted to our department for further examination of hypergastrinemia. Secretin provocation test and calcium infusion test suggested Zollinger-Ellison syndrome and percutaneous transhepatic portal venous sampling (PTPVS) demonstrated gastrinoma in the jejunum, although CT, ultrasonography and angiography could not accurately detect the location of the gastrinoma. Laparatomy findings showed a solid tumor 1.5 cm in diameter in the jejunal mesentery 5 cm distal to the ligament of Treitz, and primary gastrinoma was confirmed in the submucosa of the jejunum immediately adjacent to this tumor. An immunohistochemical study using the PAP method revealed gastrin secreting cells in the tumor. In addition to this case of jejunal gastrinoma, a review of literature in Japan and other countries was presented.  相似文献   
80.
Recently, the need for sedation in gastrointestinal endoscopy has been increasing. However, the National Health Insurance Drug Price list in Japan does not include any drug specifically used for the sedation. Although benzodiazepines are the main medication, their use in cases of gastrointestinal endoscopy has not been approved. This has led the Japan Gastrointestinal Endoscopy Society to develop the first set of guidelines for sedation in gastrointestinal endoscopy on the basis of evidence‐based medicine in collaboration with the Japanese Society for Anesthesiologists. The present guidelines comprise 14 statements, five of which were judged to be valid on the highest evidence level and three on the second highest level. The guidelines are not intended to strongly recommend the use of sedation for gastrointestinal endoscopy, but rather to indicate the policy as to the choice of appropriate procedures when such sedation is deemed necessary. In clinical practice, the final decision as to the use of sedation should be made by physicians considering patient willingness and physical condition.  相似文献   
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