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151.
Neurofibromatosis type 1 (NF1) is a common autosomal dominant disease. The Lisch nodule represents one of the most common NF1 ocular manifestations. Several studies have reported that the Lisch nodule is a melanocytic hamartoma but its pathogenesis is still debated. We have studied the histopathological and ultrastructural features of a Lisch nodule of a 50-year-old woman biopsied during an intracapsular cataract extraction. Our researches revealed that it was composed of three main cytotypes: pigmented cells, fibroblast-like cells and mast cells, showing a pattern similar to a neurofibroma. Furthermore, we hypothesize that Lisch nodules are compatible with neurofibromas.  相似文献   
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Monocyte expression and secretion of tumor necrosis factor (TNF) and TNF receptors (TNF-R) p55 and p75 was studied in patients receiving granulocyte-macrophage colony-stimulating factor (GM-CSF) after intensive chemotherapy. TNF expression and secretion of biologically active TNF was increased at regeneration compared with that of patients who had received chemotherapy alone. This effect persisted for several weeks after cessation of growth factor therapy. GM-CSF restored the responsiveness of monocytes to bacterial lipopolysaccharide (LPS), which appeared to be diminished after chemotherapy alone. Expression and secretion of TNF-R p55 and p75 by monocytes was augmented by GM-CSF therapy in association with the increase in TNF protein. We propose that GM-CSF administration after chemotherapy restores the normal responsiveness of monocytes to a secondary stimulus such as LPS and primes monocytes to respond to LPS with increased expression and secretion of TNF and TNF-R.  相似文献   
158.

Objective

The aim of this study was to compare the effect of 6% hydroxyl ethyl starch solution with 4% gelatin and Ringer’s solutions on the haemodynamic stability of patients after coronary artery bypass graft (CABG) surgery and immediately after discontinuation of cardiopulmonary bypass (CPB).

Methods

This was a randomised, double-blind clinical trial of 92 patients who were candidates for on-pump CABG. After discontinuation of CPB, all patients were transferred to the intensive care unit (ICU) and divided randomly into three groups. The first group received Ringer’s solution, the second group 4% gelatin, and the third 6% hydroxyl ethyl starch (HES) solution (Voluven). Haemodynamic parameters such as heart rate, mean arterial pressure, systolic blood pressure, diastolic blood pressure, central venous pressure, cardiac output and the presence of arrhythmias were documented.

Results

The volume needed for maintaining normal blood pressure and central venous pressure in the range of 10–14 mmHg was less in the HES group than in the other groups. The volume was similar however in the gelatin and Ringer’s groups in the first 24 hours after surgery. Urinary output in the first four and 24 hours after surgery were significantly higher in the HES group than in the other two groups. Mean creatinine levels were significantly lower in the HES group.

Conclusion

HES (6%) had a better volume-expanding effect than gelatin (4%) and Ringer’s solutions, and its short-term effects on renal function were also better than gelatin and Ringer’s solutions.  相似文献   
159.

Objectives

A wide variety of manifestations is presented in patients with Gaucher''s disease (GD), including bone, haematology and visceral disturbances. This study was conducted to ascertain the main maxillofacial abnormalities by means of clinical survey, panoramic and cone beam CT (CBCT); to compare the patient''s group with an age–sex matched control group; and to correlate clinical and radiological data.

Methods

Ten patients previously diagnosed with GD were submitted to clinical and radiological surveys (CBCT and panoramic radiographs). The examination consisted of anamnesis, extra- and intraoral examinations and analyses of each patient''s records. Imaging data were collected from the point of view of 3 observers, and the results compared with a healthy group (20 individuals) by means of statistical analysis (Fisher''s exact test).

Results

Gaucher patients had significantly more manifestations than otherwise healthy carriers. The most prevalent findings were enlarged marrow spaces, generalized osteopenia and effacement of jaw structures (mandibular canal, lamina dura and mental foramen). Here we describe a case in which thickening of the maxillary sinus mucosa was observed on CBCT rather than opacification of the sinus as seen on panoramic radiographs. Pathological fractures, root resorption and delay on tooth eruption were not observed.

Conclusions

A poor relationship could be observed between clinical and radiological data. Patients showed important bone manifestations, which require careful diagnostic and surgical planning whenever necessary. Although panoramic radiographs have shown significant differences, CBCT is more effective in pointing out differences between patients and a control group, thus showing it as an important tool for evaluation of Gaucher patients.  相似文献   
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