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81.
82.
We examined the sequential histopathological changes in the placenta from rats exposed to estrogen. 17 β-estrogiol-3-benzoate was intraperitoneally administered at 100 μg/animal/day during GD 6 to GD 8 (GD6–8 treated group), GD 9 to GD 11 (GD9–11 treated group) and GD 12 to GD 14 (GD12–14 treated group), and the placentas were sampled on GDs 11, 13, 15, 17, and 21. Fetal mortality rates were increased up to approximately 50% in the GD6–8 and 9–11 treated groups, but there was no change of fetal weight on GD 21. An increase in placental weight and a reduction in fetal/placental weight ratio were detected during GD 17 to GD 21 in the GD6–8 treated group. Histopathologically, hypoplasia of metrial gland was detected with defective development of spiral arteries in the GD6–8 and GD9–11 treated groups. A decrease in the thickness of metrial gland was observed from GD 11 onwards in the GD6–8 treated group and from GD 13 onwards in the GD9–11 treated group. The endovascular trophoblasts invaded into the spiral arteries in the deep part of metrial gland in these treated groups. The number of phospho-histone H3 positive cells was decreased on GD 11 or GD 13 in these groups. In the decidua basalis, transitory necrosis was observed with hemorrhage on GD 13 in the GD6–8 and GD9–11 treated groups. In the labyrinth zone, cystic dilatation of the sinusoid was observed with congestion in the GD6–8 treated group, resulting in an increased placental weight. Therefore, we consider that estrogen inhibits the proliferation of decidualized endometrial stromal cells in the metrial gland, and leads to metrial gland hypoplasia with less development of the spiral arteries. The reduced utero-placental blood flow is supposed to be one of the important factors for poor reproductive performance.  相似文献   
83.

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   
84.
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   
85.
86.
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   
87.

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   
88.
Castleman's disease is a rare atypical lymphoproliferative disorder. Renal manifestations, such as proteinuria, hematuria, and renal dysfunction, are common in Castleman's disease; however, a nephrotic syndrome rarely occurs. We have encountered an unusual case of Castleman's disease of the plasma cell type characterized by nephrotic syndrome because of glomerulopathy mimicking membranoproliferative glomerulonephritis. Our patient showed higher levels of circulating cytokines (interleukin-6/vascular endothelial cell-derived growth factor), the glomerular lesions not associated with immunocomplex deposition, and the resolution of nephrotic syndrome after successful corticosteroids therapy resulting in a decline in cytokines levels, thereby implicating a cytokine-induced glomerular cell injury/activation as a possible cause of the glomerular pathological changes in this case.  相似文献   
89.
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   
90.
Clinical and bacteriological data of 145 inpatients with septicemia, treated at the hospital of Chiba University School of Medicine from 1972 to 1987, were reviewed by dividing them into three stages. (stages I: 1972-76, stage II: 1978-82, stage III: 1983-87) Patients with underlying diseases have been increasing: 91.8% of the total patients in stage III. Among the patients with underlying diseases, malignant and hematological diseases occupied about 60%, and in the other diseases, congenital heart diseases have been increasing in number. As to the organisms isolated, gram positive bacteria have increased, while gram negative bacteria have decreased. In stage III, the rate of gram positive organisms and gram negative ones accounted for 43.1% and 41.2% of all the isolates from the septic patients with malignant & hematological diseases, respectively. In patients with malignant & hematological diseases, alpha-streptococcus, coagulase-negative staphylococcus, and Fusobacterium sp. have been increasing, whereas, Escherichia coli, Enterobacter sp., Klebsiella sp., and Pseudomonas aeruginosa decreasing. In patients with other underlying diseases, S. aureus, CNS, and non Fermenters have been increasing. Among the patients without underlying diseases, gram positive bacteria accounted for the major part. The decrease of gram negative organisms in patients with malignant and hematological diseases may partially depend on the introduction of polymixin B as the drug of gut decontamination. The outcome of septicemia in the patients with malignant & hematological diseases has been markedly improving through all the three stages. During stage III, episode mortality and case mortality rate proved to be 23% and 31%, respectively. The introduction of the third generation cephems has decreased the mortality rate for gram negative organisms and contributed to the improvement of the total prognosis. The prognosis was worst in the case of P. aeruginosa, showing a mortality rate of 50% during stage III. Coincidence rate of blood and other cultures have been largest in the case of P. aeruginosa, so, the drug sensitivity of the strain cultured from other sites is sometimes useful in the choice of antibiotics.  相似文献   
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