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41.
Acquired amegakaryocytic thrombocytopenic purpura (AATP) is a hematological disorder characterized by severe thrombocytopenia, probably due to an immunologically induced absence of megakaryocytes with a marked decrease or total absence of megakaryocytes in the bone marrow. AATP may be differentiated from other causes of peripheral destruction of platelets, such as immune thrombocytopenia (ITP). Currently, there are no standard treatments for AATP. However, immunosuppressive therapy including steroids, androgens, anti-thymocyte globulin (ATG), cyclophosphamide, cyclosporine A, immunoglobulins, splenectomy, and allogenic bone marrow transplantation (BMT) have all been utilized with varying degrees of success. However, a positive response in patients with AATP using steroids alone has rarely been reported in the literature.  相似文献   
42.

Objective

To assess the accuracy of chest radiography (CXR) in predicting pulmonary hypertension (PH).

Methods

We studied 108 consecutive patients with suspected PH who underwent right heart catheterization (RHC). All were PH treatment naives. Hemodynamic criteria included a mean pulmonary artery pressure > 25 mmHg at rest, and a mean pulmonary wedge pressure < 15 mmHg. Postero-anterior and lateral CXR were obtained shortly before RHC. To avoid a selection bias which could be introduced by examining only patients with suspected PH, we included in the analysis the CXR of 454 additional patients with different diagnosis: 57 with left heart failure (LHF) and pulmonary venous hypertension at RHC, 197 with chronic obstructive pulmonary disease, and 200 non-obstructed controls. CXR were examined independently by 4 raters, who were blinded to clinical, hemodynamic, and spirometric data. The diagnosis of PH was made if a prominent main pulmonary artery was associated with anyone of: isolated enlargement of right ventricle, right descending pulmonary artery > 16 mm in diameter, pruning of peripheral pulmonary vessels.

Results

Eighty-two patients had PH confirmed at RHC. Weighted sensitivity of CXR was 96.9% (95% confidence interval, 94.9 to 98.2%), and weighted specificity 99.8% (95% confidence interval, 99.6 to 99.9%). By considering the 165 patients who underwent RHC, weighted sensitivity of CXR was unchanged, and weighted specificity decreased to 99.1%. None of the patients with PH were misclassified as having LHF, and vice versa.

Conclusions

CXR is accurate in predicting PH. It may aid clinicians in selecting patients with suspected PH for hemodynamic ascertainment.  相似文献   
43.
44.
Mucormycosis is an acute and often fatal infection caused by a fungus of the Mucorales order of the Zygomycetes class. There are various clinical types, usually associated with an underlying disorder. The rhinocerebral mucormycosis is usually seen in diabetics, especially in ketoacidosis, but may also appear in healthy people. We report three cases of mucormycosis diagnosed since april 1987 through january 2001 at the Dr. Domingo Luciani Hospital, Caracas, Venezuela. Two of them had diabetes and one was apparently healthy. The most common clinical presentation of mucormycosis was the rhinocerebral infection, seen in the two diabetic patients, both of them had cavernous sinus thrombosis one with involvement of the carotid artery. The other patient with sinus involvement had no predisposing factors. All patients were treated with amphotericin B and two of them had surgical debridement of involved tissue. We emphasize the importance of an early clinical diagnosis and treatment with surgical debridement of infected tissue combined with amphotericin B.  相似文献   
45.
BACKGROUND: Over the past decades the esophageal atresia (EA) has represented the greatest challenging malformation encountered by the pediatric surgeon. Since then, there have been considerable advancements in the treatment of EA. In this paper the experience at the "Anna Meyer Children's Hospital of Florence" in regards to the surgical treatment of the EA from 1955 to present day is reported, so that the analysis of the various medical and surgical choices followed by the authors and their predecessors in this long period, can be an important learning tool for the EA management. METHODS: From 1955 to 2000, 223 newborns affected by EA with tracheoesophageal fistula (TEF) have been operated on out of a total of 250 cases of EA. Our experience has been subdivided into periods on the basis of homogeneous medical and surgical treatment adopted in that determined time. We have analyzed particularly the data of the last period 1995-2000, where there has been a well standardized protocol of treatment from the medical, surgical and intensive care points of view. RESULTS: The mortality rate has decreased from 44.8 to 3.4% with a significant reduction (p<0.001) between the years 1979-1983 and 1984-2000, due to the introduction of a perioperative treatment in the newborn intensive care unit. Moreover, a significant correlation (p<0.05) has been shown between low birthweight and associated malformations, two risk factors that however do not negatively influence the results of the treatment in the last period 1995-2000. CONCLUSIONS: A full integration between the surgeon and neonatologist is necessary in order to guarantee a good result. The risk connected to EA is not as much the surgical procedure as the presence or absence of associate malformations that are undetected in the prenatal diagnosis. It is suggested that, in order to further reduce the mortality and morbidity rate after EA correction, the number of prenatal diagnoses should be increased.  相似文献   
46.
47.
Background: Propofol (2,6-diisopropylphenol) has been shown to attenuate neuronal injury in a number of experimental conditions, but studies in models of cerebral ischemia have yielded conflicting results. Moreover, the mechanisms involved in its neuroprotective effects are yet unclear.

Methods: The authors evaluated the neuroprotective effects of propofol in rat organotypic hippocampal slices exposed to oxygen-glucose deprivation, an in vitro model of cerebral ischemia. To investigate its possible mechanism of action, the authors then examined whether propofol could reduce Ca2+-induced rat brain mitochondrial swelling, an index of mitochondrial membrane permeability, as well as the mitochondrial swelling evoked by oxygen-glucose deprivation in CA1 pyramidal cells by transmission electron microscopy. Finally, they evaluated whether propofol could attenuate the infarct size and improve the neurobehavioral outcome in rats subjected to permanent middle cerebral artery occlusion in vivo.

Results: When present in the incubation medium during oxygen-glucose deprivation and the subsequent 24 h recovery period, propofol (10-100 [mu]m) attenuated CA1 injury in hippocampal slices in vitro. Ca2+-induced brain mitochondrial swelling was prevented by 30-100 [mu]m propofol, and so were the ultrastructural mitochondrial changes in CA1 pyramidal cells exposed to oxygen-glucose deprivation. Twenty-four hours after permanent middle cerebral artery occlusion, propofol (100 mg/kg, intraperitoneal) reduced the infarct size by approximately 30% when administered immediately after and up to 30 min after the occlusion. Finally, propofol administered within 30 min after middle cerebral artery occlusion was unable to affect the global neurobehavioral score but significantly preserved spontaneous activity in ischemic rats.  相似文献   

48.
Thyroid nodules are a common occurrence in the general population, but only a small number of them are eventually diagnosed as cancers. Fine-needle aspiration biopsy (FNAB) is the most accurate and cost-effective method for the presurgical management of thyroid nodules, but it misses the differential diagnosis between thyroid follicular adenomas and follicular carcinomas. Among them, minimally invasive follicular carcinoma (MIC), also defined as encapsulated tumor, only differs from follicular adenoma for the exhibition of minimal, but entire thickness, infiltration of the capsule and/or vascular invasion. This feature cannot be assessed in FNAB and can occasionally be hard to recognize in surgical specimens. As reported in several studies, galectin-3 is a reliable marker of thyroid malignancy, but no data are available on MICs. We analyzed the immunohistochemical expression of galectin-3 in 17 MICs and 52 follicular adenomas in both preoperative paraffin-embedded cytological human thyroid sediments (cell blocks) obtained by FNAB and in the corresponding surgical specimens. Among the MICs, all surgical samples showed galectin-3 immunoreactivity in the cytoplasm, whereas 16 of 17 corresponding FNAB cell blocks were positive. No evidence of cytoplasmic galectin-3 expression was observed in 48 of 52 adenomas in both cell blocks and histological tissues. These findings indicate that galectin-3 is a reliable presurgical molecular marker of MIC, improving the accuracy of conventional FNAB. It also proves to be useful in the histopathological assessment of resected tumors having suspected malignant features.  相似文献   
49.
A multicenter, national, retrospective, and cross-sectional study of 219 hospital-based Venezuelan patients with rheumatoid arthritis (RA) was aimed to evaluate the probability of continuity of treatment with oral methotrexate (MTX). Treatment survival decreased from 92% at 12 months to 42% at 180 months, as assessed by life table analysis and the Kaplan–Meier method. Forty-seven patients stopped treatment and adverse effects (29.7%) and lack of continuous access to medication (19.1%) were the most common causes for withdrawal. MTX survival was decreased in the group with combined MTX plus leflunomide therapy, as shown by the log-rank test. Venezuelan patients with RA have a probability of continuing treatment with oral MTX comparable to non-Hispanic patient populations. However, concomitant use of leflunomide may increase the risk of interruption of MTX treatment in this RA population.  相似文献   
50.
To gain insight into the mechanisms that control the generation or maintenance of the characteristic bipolar morphology of cochlear spiral ganglion neurons, we have taken advantage of our recently developed procedure for culture of dissociated newborn mouse spiral ganglion. In these cultures, inclusion of the cytokine leukemia inhibitory factor (LIF) in the medium increases neuronal survival and the number of bipolar neurons. Here we tested effects of two other LIF-type cytokines (ciliary neurotrophic factor, CNTF; and human recombinant oncostatin M, hOSM) and of bone morphogenetic protein 4 (BMP4) on survival, morphology and neurite lengths of neurons in cultures of dissociated spiral ganglion. Like LIF, CNTF and hOSM increased neuronal survival and the number of surviving bipolar neurons. BMP4 also increased neuronal survival, but unlike LIF, CNTF and hOSM, increased the number of monopolar neurons and neurons with no neurites. In addition, population histograms demonstrate that the population lengths of the longer and shorter neurites of bipolar neurons were shorter in BMP4 containing cultures than in control or LIF cultures. When LIF and BMP4 were simultaneously added to the cultures, the BMP4 effects predominated. These experiments demonstrate that exposure to different environmental conditions can result in different morphologies in the surviving population of spiral ganglion neurons in culture.  相似文献   
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