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51.

Background

Many clinical trials have been conducted with gemcitabine- or 5-fluorouracil-based regimens as treatment for unresectable biliary tract cancer; however, the results remain unsatisfactory. Because further therapeutic improvements are required, we conducted a phase I study of arterial infusion chemotherapy using a combination of gemcitabine and 5-fluorouracil.

Methods

In the first 3 cohorts, patients were to receive an arterial infusion of gemcitabine 600, 800 or 1000?mg/m2, respectively, over 30?min on days 1 and 15, plus a continuous arterial infusion of 5-fluorouracil 300?mg/m2/day on days 1–5 and 15–19. In the final cohort, patients were to receive an arterial infusion of gemcitabine 1000?mg/m2 over 30?min on days 1 and 15, plus 5-fluorouracil 400?mg/m2/day on days 1–5 and 15–19.

Results

Eighteen patients were enrolled. In the final cohort, three of six patients experienced grade 3 non-hematological toxicities (cholecystitis, cellulitis and pneumonia). Thus, we determined the maximum tolerated doses of gemcitabine and 5-fluorouracil in arterial infusion chemotherapy to be 1000 and 400?mg/m2, respectively.

Conclusion

This regimen of gemcitabine and 5-fluorouracil is tolerable and warrants further investigation in biliary tract cancer.  相似文献   
52.
Coronavirus disease 2019 (COVID-19) has become a pandemic, and vaccines remain the only effective tools available for ending it. However, their side effects, such as syncope, which mimics sudden cardiac death, are serious concerns. We herein report 6 cases of delayed vasovagal syncope and presyncope (VVR) caused by COVID-19 vaccination among 25,530 COVID-19 patients. The prevalence of delayed VVR due to COVID-19 vaccination was 0.026%. In addition, no delayed VVR was found among 17,386 patients who received the influenza vaccine. Delayed VVR is likely to be overlooked if medical staff are not aware of this symptom. This report provides significant information regarding effects of COVID-19 vaccination.  相似文献   
53.
54.

Objective

For patients with end-stage renal disease on hemodialysis, the durability of vascular access (VA) is still far from optimal, and access survival after intervention for access failure is an important aspect. Procoagulant status is a leading cause of access failure. Coagulation-fibrinolysis imbalance can occur in hemodialyzed patients, but the influence of the imbalance has not been fully elucidated.

Methods

We prospectively examined coagulation-fibrinolysis balance to assess the risk of access failure after the intervention of revascularization in a cohort of 462 hemodialysis patients. Thrombin-antithrombin complex (TAT) and plasmin-α2-plasmin inhibitor complex (PIC) are markers for coagulation and fibrinolysis. Median follow-up was 243 days. The end point was clinical access failure: revascularization or access revision. The survival curve for VA patency was assessed using the Kaplan-Meier method and compared using the log-rank test. Cox proportional hazards regression models that allowed adjustment for baseline differences in age, sex, dialysis vintage, diabetes mellitus, and various factors (quantity of blood flow, prothrombin time-international normalized ratio, fibrin degradation products, C-reactive protein, interleukin-6, tumor necrosis factor-α, and pentraxin-3) were used.

Results

The 162 patients who reached an end point had smaller access flow volume and smaller percentage of arteriovenous fistula and higher TAT/PIC ratio. Kaplan-Meier analysis indicated that the patients with elevated TAT/PIC ratio showed poorer outcome (P < .001). On Cox regression modeling, elevated TAT/PIC was an independent risk factor for access failure (hazard ratio, 1.58; P = .03).

Conclusions

Our results suggest that coagulation-fibrinolysis imbalance is a significant risk factor for access failure and may predict VA failure in hemodialyzed patients after access intervention.  相似文献   
55.
Lymphoproliferative disorders (LPD) in patients receiving methotrexate (MTX) have gained strong attention. In this article, I reviewed the basic and clinical findings of this issue. Patients with RA possess a high risk of lymphoma, but epidemiological evidence showing an association between the use of MTX and lymphoma is still limited. Rapid regression of LPD after stopping MTX in patients with RA strongly suggests that there is a causative relationship. Genetic predisposition, accumulated inflammation, impaired generation of Epstein–Barr virus (EBV)-specific cytotoxic T lymphocytes, effects of MTX on the regulation of EBV genes, and low hypermethylation of apoptosis-related genes are relevant to the development of LPD and rapid regression after cessation of MTX. The clinical and histological characteristics of LPD in RA patients who are treated with MTX have been established, and recent data indicate that initial cessation of MTX and watchful waiting to observe an increase in peripheral lymphocyte counts have a therapeutic value. In advanced cases, various chemotherapy regimens are used, and consultation with hematologists is recommended to select the optimal treatment. There is no consensus on the treatment of RA after development of LPD, and long-term observation is necessary to investigate the safety of disease-modifying antirheumatic drugs in these patients.  相似文献   
56.
57.
Abstract

Leukotriene has been proposed as a factor of tumour induced brain oedema. Independently of its size, meningioma occasionally shows various extents of peritumoural oedema. We investigated LTC4 tissue contentsLTC4 catabolic and synthetic activity in 12 human meningiomas and their correlation with peritumoural oedema was studied. LTC4 contents were varied from 0.01 to 8.21 pg/mg tissue. When LTA4/ an unstable expoxide intermediate was incubated with tumour homogenate, LTC4 was rapidly synthesized. However; LTC4 levels generated by incubating LTA4 with each homogenate were much different in each case. Degradation of LTC4 to LTD4, LTE4, and other polar materials was also rapid by incubation with tumour homogenates. Approximately 70% of added UC4 was transformed to LTD4/ LTE4 nor 6-trans LTB4 diastereoisomers during 30 min incubation at 37 °C. The results suggested that there were significant LTC4 tissue contents and LTC4 synthetic and catabolic activity in meningiomas. Oedema index ranged from 1.0 (no peritumoural oedema) to 67.5. No significant correlationi, however', was observed not only between the LTC4 tissue contents and LTC4 synthetic or catabolic activities but also between each of these three parameters and peritumoural oedema. Thus, these results do not support a significant correlation of sulfidopeptide LTs with oedema formation in meningioma patients. Since leukotrienes are extremely unstable compounds, LTC4 tissue contents should be carefully discussed along with a consideration of rapid LTC4 synthesis and catabolism. Further role of leukotrienes in meningioma tissue should be studied.  相似文献   
58.

Background  

Nonalcoholic steatohepatitis (NASH) is a feature of metabolic syndrome. Advanced glycation end-products (AGEs) are formed by the Maillard reaction, which contributes to aging and to certain pathological complications of diabetes. A recent study has suggested that glyceraldehyde-derived AGEs (Glycer-AGEs) are elevated in the sera of patients with NASH. Furthermore, immunohistochemistry of Glycer-AGEs showed intense staining in the livers of patients with NASH. The present study aimed to examine the effect of intracellular Glycer-AGEs on hepatocellular carcinoma (Hep3B) cells.  相似文献   
59.
ABSTRACT— Hepatic venograms made in 40 authentic cases of idiopathic portal hypertension (Banti's syndrome) were compared with 13 normal venograms and venograms obtained in 88 cases of cirrhosis, and analyzed in the light of the pathological changes seen in 16 postmortem liver specimens. There were frequent anastomoses between hepatic vein radicles, approximation of middle-size branches to the liver surface, reduction in the angles between the main hepatic vein and its tributaries, and difficulty in opacifying portal vein branches in wedged retrograde portography. These angiographic alterations were corroborated by gross pathological findings which comprised displacement of middle-size hepatic vein branches closer to the liver surface and their approximation among themselves, and seem to be accounted for by the disappearance of liver parenchyma secondary to the peripheral portal circulatory failure.  相似文献   
60.
We assessed the effects of angiotensin-converting enzyme (ACE) inhibition on changes in the myocardial intracellular creatine kinase (CK) system in relation to left ventricular (LV) remodeling and function in heart failure after myocardial infarction (MI) in rats. We compared the findings at 4 weeks after MI to those at 12 weeks after MI. LV weight and chamber size were significantly increased and percent fractional shortening (%FS) was decreased in untreated MI rats compared with normal control animals both at 4 and 12 weeks after MI. Animals with MI and treated with the ACE inhibitor temocapril showed significantly reduced LV weight and chamber size and increased %FS compared with untreated MI rats at 12 weeks after MI, but not at 4 weeks after MI. At 4 weeks after MI, no significant changes were found in the total creatine and relative distribution of each CK isoenzyme in either the temocapril-treated or untreated animals with MI compared with the normal controls. In contrast, at 12 weeks after MI, untreated MI rats showed significant reductions in the total creatine and mitochondrial and MM-CK fractions and increases in the MB- and BB-CK fractions compared with the controls. The alterations in the mitochondrial and MB-CK fractions were significantly attenuated after 12 weeks of ACE inhibition. Thus, LV myocardial energy metabolism is progressively impaired and its alteration is not related to the magnitude of geometric changes and LV dysfunction after MI. Most of the beneficial effects of ACE inhibition were observed at 12 weeks after MI. Our results may provide an insight into the therapeutic strategy of ACE inhibition in chronic heart failure after MI.  相似文献   
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