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1.
The aim of this study was to assess the appropriate use of diagnostic catheterizations (DC) for the patients with suspected coronary artery disease performed in Iran. The Electronic Health Record System database and manual review of files were utilised to collect data between 2012 and 2014. Patients were categorized in three groups as appropriate, uncertain, and inappropriate usage of DC and the logistic regression was used to investigate the relationships between variables. One-quarter of the 2458 angiographies were rated as inappropriate, out of which 99% had no previous stress test. The rate of inappropriate DC between various hospitals were approximately the same. The regression showed that some risk factors (Sex, high cholesterol, smoking, chronic heart failure, renal failure, diabetes) were significantly associated with inappropriate rate.  相似文献   
2.
It is now clear that angiogenesis and angiogenesis factors are important in the pathogenesis of haematological malignancies. High pretreatment levels of serum basic fibroblast growth factor have been shown to be associated with poor prognosis in patients with non-Hodgkin's lymphoma. The aim of this study was to evaluate whether non-Hodgkin's lymphoma cells express basic fibroblast growth factor and/or its receptor (fibroblast growth factor receptor-1) and whether basic fibroblast growth factor expression correlates with basic fibroblast growth factor serum levels, intratumoral microvessel density, and patient outcome. We measured basic fibroblast growth factor by enzyme-linked immunosorbent assay in sera taken from 58 patients with non-Hodgkin's lymphoma before treatment and in 19 of them also after treatment. Pathological specimens at diagnosis were evaluated by immunohistochemistry staining using polyoclonal antibody against factor-VIII-related antigen, basic fibroblast growth factor and fibroblast growth factor receptor-1 to determine the expression of the microvessel count and basic fibroblast growth factor and fibroblast growth factor receptor-1. The lymphoma specimens demonstrated positive staining for basic fibroblast growth factor (in 23%) and fibroblast growth factor receptor-1 (in 58.5%). The patients who expressed basic fibroblast growth factor had a significantly worse progression-free and overall survival than those who did not (P=0.003 and P=0.03 respectively), while patients expressing fibroblast growth factor receptor-1 were less likely to achieve complete remission than those lacking the receptor (33% vs 65%, P=0.047). There was no correlation of basic fibroblast growth factor staining with either serum basic fibroblast growth factor levels or microvessel count. Basic fibroblast growth factor serum levels did not change significantly after treatment These results suggest that non-Hodgkin's lymphoma specimens express basic fibroblast growth factor and its receptor (fibroblast growth factor receptor-1) and this expression is associated with poor patient outcome.  相似文献   
3.
B-chronic lymphocytic leukemia (B-CLL) cells have a long survival owing to an alteration in the normal pathways of apoptosis. CLL cells have been found to produce and secrete vascular endothelial growth factor (VEGF). In addition to its major role in angiogenesis, VEGF affects cell survival by interfering with apoptosis. The aim of the present study was to investigate the expression of the VEGF receptors VEGFR-1, VEGFR-2, and VEGFR-3 on B-CLL cells, singly and combined. B-CLL cells were isolated from peripheral blood drawn from patients with CLL. Total VEGF receptor, examined in 13 samples by flow cytometry was present in all cases with mean CD19+/VEGF+ expression of 76% (range 52-92%). Specific receptor expression, examined in 27 samples by immunocytochemical methods, was positive for VEGFR-1 in all 27 patients and for VEGFR-2 and VEGFR-3 in 26 (96%). These findings suggest that the VEGF transduction pathway may be very active in CLL cells, and both its paracrine and autocrine pathways may contribute to their enhanced survival.  相似文献   
4.
Derivatives of butyric acid as potential anti-neoplastic agents   总被引:5,自引:0,他引:5  
A novel derivative of butyric acid, pivalyloxymethyl butyrate (AN-9) has been shown, in vitro, to: (a) induce cytodifferentiation and inhibit the proliferation of leukemic cells; (b) inhibit the growth and formation of Lewis lung carcinoma colonies in semi-solid agar. AN-9 affect cells at about 10-fold lower concentration and at a faster rate than does butyric acid. The pivalyloxymethyl esters of propionic, isobutyric and valeric acids do not elicit effects similar to those of AN-9, while the isobutyryloxymethyl butyrate does, which strongly suggests that the activity of AN-9 stems from intracellular metabolic degradation of the pro-drug to butyric acid. In vivo, AN-9, increased the survival of mice in Lewis lung carcinoma primary cancer model and significantly decreased the number of lung lesions of the animals inoculated with highly metastatic cells, but did not affect their life span. Acute LD50 studies have shown that AN-9 possesses low toxicity. These results suggest that AN-9 is a potential anti-neoplastic agent as well as a tool for investigation of the differentiation induction mechanism.  相似文献   
5.
Expression of cytoplasmic islet cell antigens by rat pancreas   总被引:2,自引:0,他引:2  
A major problem in standardization of the islet cell cytoplasmic antibody (ICA) assay is variation in sensitivity of the different human pancreas substrates used in individual laboratories. To circumvent this problem, we have developed an assay that utilizes Wistar-Furth rat pancreas as substrate, an anti-islet monoclonal antibody (A2B5) to identify islets and fluorescein-conjugated protein A to identify patient autoantibodies. Sera from 85 control subjects, 27 type I diabetics, and 17 subjects at high risk for developing type I diabetes were assayed in parallel with our standard ICA assay on human pancreas substrate and with Wistar-Furth rat pancreas as substrate. Two sera from control subjects (2 of 85) were ICA positive with rat pancreas compared to 1 of 85 with human pancreas substrate. Sera from 11 of 27 type I diabetics and 15 of 17 sera from high-risk subjects were ICA positive with either rat or human pancreas substrate. A correlation between the specific islet fluorescence readings on human and rat pancreas sections was found with sera from high-risk and control subjects. Furthermore, end-point titers of an ICA-positive serum were identical with both assays. Finally, incubation of an ICA-positive serum with glycolipids, extracted from either human or Wistar-Furth rat pancreas, blocked subsequent ICA binding. These findings suggest that Wistar-Furth rat pancreas expresses an identical or similar autoantigen to human pancreas.  相似文献   
6.
The antitumor activity of novel prodrugs butyric acid was examined. The in vitro effect of the compounds on induction of cytodifferentiation and on inhibition of proliferation and clonogenicity showed that (pivaloyloxy)methyl butyrate (1a) (labeled AN-9) was the most active agent. SAR's suggested that its activity stemmed from hydrolytically released butyric acid. In vivo, 1a displayed antitumor activity in B16F0 melanoma primary cancer model, manifested by a significant increase in the life span of the treated animals. Murine lung tumor burden, induced by injection of the highly metastatic melanoma cells (B16F10.9), was decreased by 1a. It also displayed a significant therapeutic activity against spontaneous metastases which were induced by 3LL Lewis lung carcinoma cells. Moreover, 1a has the advantage of low toxicity, with an acute LD50 = 1.36 +/- 0.1 g/kg (n = 5). These results suggest that 1a is a potential antineoplastic agent.  相似文献   
7.
B-Chronic lymphocytic leukemia (B-CLL) is an example of a human malignancy caused by alterations in the pathways of programmed cell death. In this disease the anti-apoptotic protein, bcl-2, is overexpressed and may lead to the prolonged survival of a malignant CLL clone. In the present study we examined the expression of bcl-2 and bax, which has an antagonistic role against the function of bcl-2, in cells from CLL patients at different stages of the disease, by immunoblot analysis. A direct association between the stage of the disease and the level of bcl-2 in the patients' cells was observed. At stages A and B, 33% and 29% of patients, respectively, expressed high levels of bcl-2, as opposed to 80% of patients at stage C (p= 0.019). Bax level was not significantly associated with the stage of the disease, although patients at stage C had higher levels of bax. In this study we found a trend of association between bcl-2 and bax levels. Analysis including all patients revealed that 65% of the patients who expressed high levels of bcl-2 had high levels of bax (p = 0.058). Of patients in stage C, 45% expressed high levels of both bcl-2 and bax while 50% and 42% of patients at stages A and B had low levels of both proteins.  相似文献   
8.

Purpose

Exposure of sclera below the iris in natural head positions is aesthetically undesirable. Studies on post-surgical changes in inferior scleral exposure following orthognathic surgery are scarce and mostly retrospective. The aim of this clinical trial is to examine the effect of Le Fort I osteotomy, a procedure for correction of malocclusion and maxillo-mandibular deformities, on the inferior scleral exposure and overall scleral surface area in skeletal class III patients.

Materials and methods

This trial was performed on 40 eyes of 20 skeletal class III patients undergoing Le Fort I osteotomy without impaction (n = 20 eyes) and with impaction (n = 20 eyes). Standard true-size frontal photography was performed pre-operatively and post-operatively at 6 months. After measuring the overall eye height and the height of visible inferior sclera, the ratio of inferior sclera to overall eye height (S:E) was calculated three times. Also, overall surface area of the sclera was measured three times. The average of three attempts was considered the main measurement. Changes in the sclera after the surgery and between both methods were compared.

Results

The average age of patients (9 men, 11 women) was 24.5 years. Age and gender were balanced between the two groups (P > 0.05). S:E ratios decreased in both groups after surgery (P < 0.05, Wilcoxon test). The decrease was greater in the impaction group (P < 0.05, Mann–Whitney test). Similar results were observed for overall sclera surface areas.

Conclusion

Maxillary advancement, with or without impaction, reduced the inferior scleral exposure and overall scleral surface area. The effect was more pronounced in the impaction group.  相似文献   
9.
A 37-year-old woman originally presented in May 2003 with a nonhealing, painless ulcer on the plantar surface of her right foot that had been slowly increasing in size for the previous 1.5 years. Two weeks before presentation, a biopsy of the lesion, performed at another institution, had indicated a probable verrucous carcinoma. After preoperative workup, the patient underwent resection of the lesion, with clear margins and full-thickness skin grafting. The final pathologic findings were not consistent with verrucous carcinoma. A recurrent lesion was noted during a follow-up visit, and a second biopsy revealed a hyperkeratotic papillomatous verrucous lesion, type unclassified. No viral particles were isolated in the random biopsy samples. This recurrent lesion was refractory to treatment with topical acyclovir. Subsequent treatments consisted of imiquimod and CO(2) laser ablation, which succeeded in reducing the lesion. Verrucous lesions can be frustrating, and the diagnosis of epithelioma cuniculatum can be difficult to prove. We report a case highly suggestive of but not definitively diagnosed as epithelioma cuniculatum and summarize the literature on this entity.  相似文献   
10.
BACKGROUND: CD154 mediates key facets of humoral and cellular immunity to alloantigens, and is tolerogenic to influenza antigens in primates. Barriers to CD154-based tolerance induction for primate cardiac allografts have not previously been defined. METHODS: Heterotopic cardiac allograft outcomes in cynomolgus monkeys treated with a CD154 inhibitor, IDEC-131 (n=27), were compared to no treatment (n=4) or cyclosporine A (n=6). RESULTS: CD154 blockade significantly prolonged median allograft survival, from 6.2 (range 6, 7, n=4) days in untreated controls, to 39 (8,112, n=16) days with intensive monotherapy and 93 (>25, 386; n=3) days with added antithymocyte globulin (ATG), but did not yield tolerance. Alloantibody production was delayed but not prevented by IDEC-131 alone or with ATG, and was exacerbated by infusion of donor bone marrow (n=8). Expression of ICOS was prominent in graft infiltrating lymphocytes, and preceded elaboration of antidonor antibody and vasculopathy. CONCLUSION: CD154 monotherapy modulates primate cardiac alloimmunity, but does not readily induce tolerance. Targeting alternative costimulation pathways, including ICOS, may facilitate tolerance induction based on CD154 blockade.  相似文献   
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