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51.
AIMS: The study evaluated the correlation between pretreatment serum lactate dehydrogenase (LDH) levels with the stage of disease and its clinical prognostic value. METHODS: Pretreatment serum LDH of 1421 patients with osteosarcoma of the extremity were assessed to investigate whether the enzyme correlates with the stage of the tumor. In 860 assessable patients with localized disease, treated according to 10 different protocols of adjuvant (four) and neoadjuvant chemotherapy (six), we also evaluated the correlation between the serum levels of LDH and outcome. RESULTS: According to the stage of disease, the rate of high serum level of LDH was significantly higher in 199 patients with metastatic disease at presentation than in 1222 patients with localized disease (36.6% vs 18.8%; P < 0.0001). In these patients, the 5-year disease-free survival was 39.5% for patients with high LDH levels and 60% for those with normal values. The 5-year disease-free survival correlated with serum level of LDH at univariate and multivariate analysis, although it lost its significance when histologic response to chemotherapy was also considered in the multivarite analysis. CONCLUSIONS: Serum LDH has a prognostic value and it should be considered in evaluating the results of therapeutic trials of chemotherapy, as well as defining a category of patients at high-risk of relapse to be treated with a more aggressive regimen.  相似文献   
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Acute mediastinitis is an uncommon and potentially devastating infection. Generally, mediastinitis occurs as a postoperative infection following median sternotomy. We describe a case of acute mediastinitis in a patient with ischaemic heart disease, secondary to the spread of cutaneous infection of the chest wall in the application site of transdermal nitroglycerine patches.  相似文献   
54.
Patients affected by Pfeiffer syndrome generally present with syndromic craniosynostosis and typical limb defects including broad thumbs, wide halluces with varus deformity, toe syndactyly and sometimes elbow ankylosis. This autosomal dominant condition can be caused by mutations in either fibroblast growth factor receptor gene type 1 or 2 (FGFR1 or FGFR2). We report four new affected families showing an FGFR1 P252R mutation and emphasize the characteristic malformations of the feet in this form of Pfeiffer syndrome. In one family this was the only abnormality.  相似文献   
55.
STUDY OBJECTIVE: To verify the value, feasibility, and reliability of transvaginal hydrolaparoscopic ovarian drilling using the bipolar VersaPoint system to treat clomiphene-resistant, anovulatory women with polycystic ovary syndrome. DESIGN: Prospective clinical study (Canadian Task Force classification II-2). SETTING: University teaching hospital. PATIENTS: Twenty-eight women. INTERVENTION: Transvaginal hydrolaparoscopic ovarian drilling using the bipolar VersaPoint spring electrode. MEASUREMENTS AND MAIN RESULTS: After the surgical procedure, ovulation occurred spontaneously in 66.7% of women. Thirteen pregnancies occurred; eight were spontaneous, and four were achieved after induction of ovulation with clomiphene citrate and one after stimulation with gonadotropins. In 21 women whose infertility was due exclusively to anovulation, the cumulative pregnancy rate was 38% at 3 months and 76% at 6 months. No ovarian hyperstimulation or abortion occurred. The single complication was bleeding from an ovary that required conversion to laparoscopy. CONCLUSION: Transvaginal hydrolaparoscopic ovarian drilling with the bipolar VersaPoint system is a useful therapeutic option in these women.  相似文献   
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Peripheral ataxia is reported in a juvenile case of Alpers-Huttenlocher disease (AHD). Neurophysiological and neuropathological investigations revealed a central-peripheral axonopathy, affecting the deep sensation carried by the peripheral nerve fibres and the posterior tracts of the cord, due to neuronal loss of the sensory ganglia. Involvement of the sensory pathways is regarded as a major feature of juvenile AHD. Received: 28 October 2002, Received in revised form: 2 January 2003, Accepted: 15 January 2003 Present address: A. Polo, MD, Neurology Unit, Hospital of Piove di Sacco (PD), Italy Correspondence to: A. Simonati, MD  相似文献   
58.
We investigated the function of Xrx1 during Xenopus retinogenesis. Xrx1 overexpression lengthens mitotic activity and ectopically activates the expression of markers of undifferentiated progenitors in the developing retina. We assayed Xrx1 ability to support proliferation with a cell-autonomous mechanism by in vivo lipofection of single retinal progenitors. Xrx1 overexpression increases clonal proliferation while Xrx1 functional inactivation exerts the opposite effect. We also compared the effects of Xrx1 with those of the cyclin-dependent kinase cdk2, a strong mitotic promoter. Despite the similar increase in clonal proliferation displayed by both factors, Xrx1 and cdk2 act differently on retinal cell fate determination. cdk2/cyclinA2 lipofected retinas show a decrease in early-born cell types as ganglion cells and cones and an increase in late-born types such as bipolar neurons. On the contrary, Xrx1 lipofected retinas show no changes in the proportions of the different cell types, thus suggesting a role in supporting multipotency of retinal progenitors.  相似文献   
59.
PURPOSE: To evaluate the possible role of multislice spiral computed tomography (MSCT) as the sole imaging examination in the preoperative assessment of potential donors undergoing adult-to-adult living donor liver transplantation (LDLT). MATERIALS AND METHODS: Fifteen patients underwent MSCT with 0.5-second gantry rotation time. Pre- (4 X 2.5 mm collimation) and post-contrast (4 X 1 mm collimation) acquisitions during arterial and portal venous phases were performed after intravenous administration of 140 ml of non ionic contrast agent at 4-5 ml/s, with a delay time of 25 and 60 seconds, respectively. Pre-contrast scans with 80 and 140 kVp were acquired at the same level used to assess liver density. Real-time interaction with the post-contrast 3D data set was performed on a dedicated workstation to determine total and lobar liver volume, and to assess arterial and venous vascular anatomy. RESULTS: Steatosis was found in three patients, who as a consequence were excluded as possible candidates. MSCT correctly identified five cases of arterial anatomical variations: two cases of the right hepatic artery arising from the superior mesenteric artery, two cases of the common hepatic artery arising from the superior mesenteric artery and one case of the left hepatic artery arising from left gastric artery. In two cases portal trifurcation was considered a criterion for exclusion. A 4% error in the liver volume calculation was found at surgery, in no case considered significant. Two patients underwent surgery and three have been short-listed. CONCLUSIONS: MSCT enables complete preoperative evaluation of potential donors undergoing LDLT. Total and lobar volume determination provided accurate and reproducible information. MSCT enabled correct surgical planning without intra-operative complications. One of the limits of the technique was the poor visualization of the biliary anatomy with the need to perform an intraoperative cholangiography in all the patients.  相似文献   
60.
Granular cell odontogenic tumours (GCOT) are rare neoplasms that usually manifest a benign clinical behaviour. We document the first case of GCOT exhibiting clinico-pathological features of malignancy that occurred in the maxilla of a 40-year-old male. The lesion appeared as an intra-oral polypoid mass and, at CT scan, as a poorly demarcated radiolucency eroding the cortical plate. Histologically, the tumour consisted of clusters of granular cells, exhibiting nuclear pleomorphism, prominent nucleoli and mitotic figures, and spindle cells in a collagenous stroma containing cementicles and strands of odontogenic epithelium. Morphologic transition from fibroblast-like to granular cells was frequently detected. The tumour cells extensively invaded the oral and respiratory mucosae and the adjacent soft tissues and exhibited vimentin and CD 68 immunoreactivity and high (21%) Ki 67 immunolabeling but not cytokeratins, E.M.A. actin, desmin, myosin or S-100 protein positivity. The patient experienced tumour recurrence 16 months after radical surgery. While the histogenesis of GCOT remains to be clarified, we document the existence of a malignant counterpart of this tumour and propose the name of malignant GCOT or granular cell odontogenic sarcoma for such entity.  相似文献   
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