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71.
Mitochondrial diseases in children: neuroradiological and clinical features in 17 patients 总被引:7,自引:0,他引:7
Mitochondrial diseases result from structural, biochemical or genetic defects of mitochondria, which contain the respiratory
chain. They usually affect children and young adults. We report the CT and MRI findings in 17 patients under 14 years of age,
the youngest reported to date, with various mitochondrial diseases. Although imaging studies may be normal negative in the
early stages, follow-up usually shows many abnormalities, which depend on clinical status and the disease. We have recognised
a spectrum of findings that can be divided into four patterns: nonspecific myelin lesions (8/17); grey-matter nuclei involvement
(6/17); a leukodystrophic pattern; and calcification of the brain (1/17), although mixed forms, particularly myelin and grey-matter
lesions are frequent.
Received: 18 February 1999 Accepted: 7 May 1999 相似文献
72.
Watters AD Stacey MW Going JJ Grigor KM Cooke TG Sim E Bartlett JM 《Urologia internationalis》2001,67(3):235-239
INTRODUCTION/OBJECTIVE: N-acetyltransferase 2 (NAT2), mapped to 8p22, is a polymorphic enzyme which metabolizes aromatic amines. Loss of heterozygosity of 8p22 is associated with an increased risk of bladder cancer. This study evaluated NAT2 and chromosome 8 in sequential tumours from bladder cancer patients to determine if NAT2 alterations increase the risk of progression. MATERIALS AND METHODS: Thirty-seven sequential carcinomas from 19 patients were assessed using fluorescence in situ hybridization. RESULTS: Five carcinomas showed loss of NAT2; 4 of these were from pTa/pT1 tumours. Polysomy 8 was observed in 4 of 14 (29%) primary carcinomas (pTa/pT1), in 4 of 12 (33%) pTa/pT1 recurrences, and in 90% (9/10) of the detrusor muscle invasive tumours (pT2+). 6 of 8 (75%) locally invasive tumours with polysomy 8 were from patients who subsequently developed disease progression (pT2+). In total, 13.5% (5/37) of the carcinomas were abnormal for NAT2, and 46% (17/37) were abnormal for chromosome 8 copy number. Polysomy 8 was associated with high grade (p = 0.01) and stage (p = 0.03) and disease progression (p = 0.03). CONCLUSION: Whilst there does not appear to be an association between loss of NAT2 and risk of progression in transitional cell carcinoma, the high rate of polysomy of chromosome 8 implies that other genes on this chromosome significantly influence disease progression. 相似文献
73.
Choong PF Petersen IA Nascimento AG Sim FH 《Clinical orthopaedics and related research》2001,(387):191-199
Radiotherapy and limb-preserving surgery has replaced amputation and compartmental resection for treatment of soft tissue sarcomas. However, the role of radiotherapy in low-grade tumors remains unclear. This study reviews the outcomes of 132 patients who received multimodality treatment for low-grade soft tissue sarcoma. Large primary tumors (> 5 cm) and the absence of radiotherapy correlated with local recurrence. Radiotherapy was most effective in patients operated on with marginal margins. Patients who were treated with wide surgical margins or had small tumors (< or =5 cm) showed no benefit with adjuvant radiotherapy. Size greater than 5 cm and local recurrence correlated with metastasis. Radiotherapy appears to be important in the management of low-grade soft tissue sarcoma. The principles of local treatment for low-grade soft tissue sarcoma should be the same as for high-grade tumors with a combination of surgery and adjuvant radiotherapy. In a subset of patients with small and widely excised tumors, consideration may be given to withholding radiotherapy. Local recurrence and metastasis from low-grade soft tissue sarcoma may occur as long as 1 decade after primary tumor resection. Long-term review of patients with low-grade tumors may be indicated. 相似文献
74.
BACKGROUND: Little information is available concerning dosage and optimal initiation of thromboprophylactic therapy with low-molecular-weight heparin (enoxaparin) in nonelective hip surgery. The aim of our prospective study was to evaluate the incidence of clinically apparent deep vein thrombosis (DVT), pulmonary embolism (PE), and major hemorrhage in patients receiving thromboprophylaxis with enoxaparin undergoing hip surgery after hip fracture. METHOD: From 946 consecutive patients admitted with hip fractures, 897 were operated on and received enoxaparin according to the following regimen: Preoperative heparinization from time of admission onwards. Administration of 60 mg enoxaparin, in two doses (20 and 40 mg subcutaneously), during the first 5 days postoperatively. Prophylaxis for a minimum of 5 weeks (40 mg daily). RESULTS: Clinical signs of DVT were present in 37 patients (4.2%), who all underwent venography. In five patients, DVT was confirmed (0.6%). None of these patients suffered from PE. Another four patients (0.4%) developed clinical signs of PE, and suspected diagnosis was confirmed by computed tomographic scan in two (0.2%). No deaths because of PE were observed. Major hemorrhage occurred in 42 patients (4.7%), there was one death from hemorrhage caused by an intracerebral event. No case of heparin-induced thrombocytopenia type II was observed. CONCLUSION: Thromboprophylaxis with 60 mg enoxaparin daily, in split doses, starting before surgery, is safe and appropriate in patients with hip fractures. Clinically apparent DVT and PE are rarely observed, and bleeding complications are comparable to those occurring with a conventional thromboprophylactic regimen. 相似文献
75.
Bertoletto PR Fagundes DJ De Jesus Simões M Oshima CT De Souza Montero EF Simões RS Fagundes AT 《Microsurgery》2007,27(4):224-227
To examine the apoptosis expression in the intestinal mucosa in accordance of different periods of hyperbaric oxygen (HBO) treatment, rats were submitted to 60 min of mesenteric artery and vein ischemia and 60 min of reperfusion occlusion. A group (G-IR) was the control and HBO was applied in the ischemia (GHBO-I), reperfusion (GHBO-R), and ischemia and reperfusion time (GHBO-IR). After 60 min of reperfusion, samples of small bowel were prepared for immunohistochemical expression of caspase-3. The expression of caspase-3 was significantly inferior when HBO was administered in the ischemia (0.16 +/- 0.01) in comparison with the control (0.70 +/- 0.08), but HBO in the further reperfusion (0.84 +/- 0.03) or both ischemia and reperfusion time (0.42 +/- 0.05) was significantly worse. There was a connection between HBO, small bowel I/R injury, and mucosa apoptosis. The favorable effect was obtained when HBO was administered early in the ischemia time. 相似文献
76.
Vitor Costa Sim?es Bruno Santos Sara Magalh?es Gil Faria Donzília Sousa Silva José Davide 《International journal of surgery case reports》2014,5(8):547-550
INTRODUCTION
Duodenum is the second most frequent location for a diverticulum in the digestive tract. Complications are rare and perforation was only reported in less than 200 cases.PRESENTATION OF CASE
A 79-year-old female was admitted to Emergency Department with abdominal pain and vomiting for the last 24 h. A CT scan was performed and moderated extra-luminal air was identified. During surgery a fourth portion perforated duodenal diverticulum was diagnosed and duodenal resection was performed.DISCUSSION
First reported in 1710, the incidence of duodenal diverticula can be as high as 22%. Nevertheless complications are extremely rare and include haemorrhage, inflammation, compression of surrounding organs, neoplastic progression, cholestasis and perforation.As perforations are often retroperitoneal, symptoms are nonspecific and rarely include peritoneal irritation, making clinical diagnose a challenge.CT scan will usually present extra-luminal retroperitoneal air and mesenteric fat stranding, providing clues for the diagnosis.Although non-operative treatment has been reported in selected patients, standard treatment is surgery and alternatives are diverse including diverticulectomy or duodenopancreatectomy.CONCLUSION
Perforated diverticula of the fourth portion of the duodenum are extremely rare and current evidence still supports surgery as the primary treatment modality. 相似文献77.
Carlos de Paula Eduardo Ana Cecilia Corrêa Aranha Alyne Simões Marina Stella Bello-Silva Karen Muller Ramalho Marcella Esteves-Oliveira Patrícia Moreira de Freitas Juliana Marotti Jan Tunér 《Lasers in medical science》2014,29(4):1517-1529
Recurrent herpes labialis is a worldwide life-long oral health problem that remains unsolved. It affects approximately one third of the world population and causes frequent pain and discomfort episodes, as well as social restriction due to its compromise of esthetic features. In addition, the available antiviral drugs have not been successful in completely eliminating the virus and its recurrence. Currently, different kinds of laser treatment and different protocols have been proposed for the management of recurrent herpes labialis. Therefore, the aim of the present article was to review the literature regarding the effects of laser irradiation on recurrent herpes labialis and to identify the indications and most successful clinical protocols. The literature was searched with the aim of identifying the effects on healing time, pain relief, duration of viral shedding, viral inactivation, and interval of recurrence. According to the literature, none of the laser treatment modalities is able to completely eliminate the virus and its recurrence. However, laser phototherapy appears to strongly decrease pain and the interval of recurrences without causing any side effects. Photodynamic therapy can be helpful in reducing viral titer in the vesicle phase, and high-power lasers may be useful to drain vesicles. The main advantages of the laser treatment appear to be the absence of side effects and drug interactions, which are especially helpful for older and immunocompromised patients. Although these results indicate a potential beneficial use for lasers in the management of recurrent herpes labialis, they are based on limited published clinical trials and case reports. The literature still lacks double-blind controlled clinical trials verifying these effects and such trials should be the focus of future research. 相似文献
78.
Pablo León-Atance Nicolás Moreno-Mata Federico González-Aragoneses Miguel Ángel Cañizares-Carretero Enrique Poblet-Martínez Marta Genovés-Crespo María Dolores García-Jiménez Antonio Francisco Honguero-Martínez Carlos Alberto Rombolá Carlos María Simón-Adiego Rafael Peñalver-Pacual Emilio Álvarez-Fernández 《Archivos de bronconeumologia》2012,48(2):49-54
IntroductionIn the scientific literature, contradictory results have been published on the prognostic value of the loss of expression of blood group antigen A (BAA) in lung cancer. The objective of our study was to analyze this fact in our surgical series.Patients and methodsIn a multicenter study, 402 non-small-cell lung cancer (NSCLC) patients were included. All were classified as stage-I according to the last 2009-TNM classification. We analyzed the prognostic influence of the loss of expression of BAA in the 209 patients expressing blood group A or AB.ResultsThe 5-year cumulative survival was 73% for patients expressing BAA vs 53% for patients with loss of expression (P=.03). When patients were grouped into stages IA and IB, statistical significance was only observed in stage I-A (P=.038). When we analyzed the survival according to histologic type, those patients with adenocarcinoma and loss of expression of BAA had a lower survival rate that was statistically very significant (P=.003). The multivariate analysis showed that age, gender and expression of BAA were independent prognostic factors.ConclusionsThe loss of expression of blood group antigen A has a negative prognostic impact in stage I NSCLC, especially in patients with adenocarcinoma. 相似文献
79.
Background
There has been an increasing trend toward contralateral prophylactic mastectomy (CPM) in the management of breast cancer (BCa). This study??s objective was to compare clinicopathologic characteristics of BCa patients who elected CPM to those who elected unilateral total mastectomy (UTM) and to determine whether CPM improved survival.Methods
Comparison was performed on 355 patients with stage 0?CIII BCa matched by age and stage who underwent mastectomy from 1995 to 2008: 177 patients had CPM; 178 patients had UTM. Clinicopathological characteristics and survival outcomes were analyzed.Results
Women who underwent preoperative MRI were twice as likely to have CPM (40.9 vs. 19.7%, P?0.001). MRI identified additional suspicious foci in 45% CPM and 19% UTM. Patients with history of previous breast biopsies, family history, or BRCA mutation were more likely to choose CPM than UTM (40.1 vs. 24%, P?=?0.001; 64.3 vs. 41.4%, P?0.001; 20.3 vs. 6.5%, P?=?0.04, respectively). CPM patients elected nipple preservation (26 vs. 5.2%, P?0.001) and immediate reconstruction more often (92.2 vs. 73.5%, P?0.001); UTM patients were more likely to have attempted breast conservation prior to mastectomy (52.8 vs. 39.5%, P?=?0.01). CPM identified occult BCa in 11 patients (6.6%), and three UTM patients (1.7%) developed contralateral BCa. With median follow-up of 61?months, by univariable/multivariable analyses, CPM did not improve overall, disease-free, or distant metastases-free survival.Conclusion
Factors that may influence choice of CPM included preoperative MRI, history of prior breast biopsies, immediate reconstruction, nipple preservation, family history, and BRCA status. Those who chose CPM did not have improved survival. 相似文献80.
Chung IS Kim HY Shin YH Ko JS Gwak MS Sim WS Kim GS Lee SK 《Clinical transplantation》2012,26(4):539-543
A characteristic pattern of hemodynamic changes that may occur in reperfusion phase of liver transplantation (LT) is known as post-reperfusion syndrome (PRS). In this study, we determined the frequency of PRS and evaluated possible predictors of PRS. The medical records of 152 patients who underwent living donor LT were reviewed. PRS was defined as a decrease in mean arterial pressure of more than 30% from the baseline value for more than one min during the first five min after reperfusion. The frequency of PRS was determined, and patients were divided into two groups: PRS group and non-PRS group. Donor factors, preoperative and intraoperative recipient factors, and postoperative outcomes were compared between the two groups. PRS occurred in 58 recipients (34.2%). Preoperative model for end-stage liver disease scores of recipients and percentage of graft steatotic changes were higher in PRS group. PRS group showed higher heart rates and lower hemoglobin values preoperatively. Before reperfusion, PRS group received more transfusion and their urine output was less than that of non-PRS group. Postoperatively, peak bilirubin during the first five d after LT was higher in PRS group. In conclusion, both severity of liver disease and graft steatosis may increase risk for PRS in LT. Further prospective studies of PRS in its relationship to outcome are indicated. 相似文献