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61.
Proto  AV 《Radiology》1992,183(3):593
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62.
Electroencephalographic (EEG; Be-plus Eb-Neuro) and stabilogram (RGM) data were simultaneously recorded in 19 elite karate and 18 fencing athletes and in 10 non-athletes during quiet upright standing at open- and closed-eyes condition in order to investigate the correlation between cortical activity and body sway when the visual inputs are available for balance. Our working hypothesis is that, at difference of non-athletes, athletes are characterized by enhanced cortical information processing as indexed by the amplitude reduction of EEG oscillations at alpha rhythms (about 8-12 Hz) during open- referenced to closed-eyes condition (event-related desynchronization, ERD). Balance during quiet standing was indexed by body "sway area". Correlation between alpha ERD and event-related change of the sway area was computed by a non-parametric test (p<0.05). It was found that alpha ERD (10-12 Hz) is stronger in amplitude in the karate and fencing athletes than in the non-athletes at ventral centro-parietal electrodes of the right hemisphere (p<0.02). Furthermore, there was a statistically significant correlation in the karate athletes between right ventral centro-parietal alpha ERD and body sway area (r=0.61; p<0.008): specifically, the greater the alpha ERD, the greater the percentage reduction of the body sway area when the visual inputs were available. These results suggest that parasylvian alpha ERD of the right hemisphere may reflect the cortical information processing for the balance in elite athletes subjected to a long training for equilibrium control.  相似文献   
63.
A series of chemically oversulphated galactosaminoglycans (SO3H:COOH ratio > or = 2) were tested in vitro as antiviral agents against human immunodeficiency virus type 1 (HIV-1), the aetiological agent of AIDS, and against herpes simplex virus type 1 and human cytomegalovirus, two agents responsible for opportunistic infections in HIV-infected people. The oversulphated derivatives displayed an increase in activity ranging from one to four orders of magnitude against the three viruses, as compared to the natural parent compounds (SO3H:COOH, ratio approx. 1). The antiviral activity of these polyanions appears to be favoured by a high degree of sulphation and a high molecular mass. An oversulphated dermatan, with a SO3H:COOH ratio of 2.86 and molecular mass of 23.2 kDa, was the most potent anti-HIV-1 compound (EC50 0.04 microgram/ml). A second oversulphated dermatan, with a SO3H:COOH ratio of 2.40 and molecular mass of 25 kDa, displayed the highest activity against HSV-1 (EC50 0.01 microgram/ml). An oversulphated chondroitin, with a SO3H:COOH ratio of 2.80 and molecular mass of 17.3 kDa, was the strongest anti-HCMV agent (EC50 0.4 microgram/ml). In view of the absence of the side-effects typical of heparin-like compounds, a combination of these derivatives could have therapeutic potential.  相似文献   
64.

Background

Hepatocellular carcinoma (HCC) is an indication for liver resection or transplantation (LT). In most centers, patients whose HCC meets the Milan criteria are considered for LT. The first objective of this study was to analyze whether there is a correlation between the pathologic characteristics of the tumor, survival and recurrence rate. Second, we focused our attention on vascular invasion (VI).

Methods

From January 1997 to December 2007, a total of 196 patients who had a preoperative diagnosis of HCC were included. The selection criteria for LT satisfied both the Milan and the San Francisco criteria (UCSF). Demographic, clinical, and pathologic information were recorded.

Results

HCC was confirmed in 168 patients (85.7%). The median follow-up was 74?months. The pathologic findings showed that 106 patients (54.1%) satisfied the Milan criteria, 134 (68.4%) the UCSF criteria of whom 28 (14.3%) were beyond the Milan criteria but within the UCSF criteria, and 34 (17.3%) beyond the UCSF criteria. VI was detected in 41 patients (24%). The 1-, 3-, and 5-year overall survival rates were 90%, 85%, and 77%, respectively, according to the Milan criteria and 90%, 83%, and 76%, respectively, according to the UCSF criteria (P?=?NS). In univariate and multivariate analyses, tumor size and VI were significant prognostic factors affecting survival (P?400?ng/ml and tumor grade G3.

Conclusions

Tumor size and VI were the only significant prognostic factors affecting survival of HCC patients. Primary liver resection could be a potential selection treatment before LT.  相似文献   
65.
Hepatitis B infection is the main cause of liver related mortality in many countries including Iran. Liver transplantation in cirrhosis due to HBV infection before 1990 was an absolute contraindication. Recurrent infection was a significant event in post liver transplant setting and resulted in increased risk of graft failure and death except successful transplanted individuals. Advances in antiviral prophylaxis have now made graft reinfection majority patients as a rare event. Graft and patient survival have been improved significantly during the past two decades, and consequences of transplantation for hepatitis B virus are now superior to those achieved for most other indications. This has encouraged many centers including the major liver transplantation center of Iran, in Shiraz, to provide liver transplantation to more patients with HBV related end stage liver disease. Management of these patients begins before transplantation along with special care after transplantation. There are some myths and doubts in the management of these patients and one should always balance the cost and efficiency. One of the major concerns is the high economic and social cost of recurrence and all possible efforts should be performed to avoid the ominous consequences of reinfection. Having a clear scientific grasp on the management of HBV cirrhosis before and after liver transplantation, options and protocols, and changing the concept which HBV infected are contraindicated ones for liver transplantation, and future hopes in increasing patients survival after liver transplantation using the new nucleosides analogues and availability of hepatitis B immunoglobulin in the transplantation setting. This scientific report paper outlines the insights communicated at the HBV and liver transplantation symposium during 10th Congress of the Iranian Society for Organ Transplantation, May 2011, Shiraz, Iran.  相似文献   
66.
This case report discusses the unusual presentation and ultrasound features of a solitary fibrous tumour of the face. Solitary fibrous tumour is an uncommon form of soft tissue tumour which, although seen predominantly within the lung pleura, can occur throughout the body in sites such as the peritoneum, mediastinum and head and neck. Ultrasound is an excellent imaging modality in the assessment of soft tissue masses in the head and neck. The ultrasound features demonstrated by this example of solitary fibrous tumour are reviewed. This report also highlights that ultrasound alone is ultimately limited in reaching a definitive diagnosis. The roles of other investigations such as ultrasound-guided biopsy and cross-sectional imaging are discussed.  相似文献   
67.
Data on the distribution of beta thalassemia among over 6,000 Melanesians reveals a major difference in the carrier rates between populations in the malarious coastal regions of New Guinea and those living in the historically malaria-free Highlands. The island of Maewo in Vanuatu has a particularly high incidence of beta + thalassemia associated with a single restriction enzyme haplotype. Direct cloning into a plasmid vector and sequence analysis demonstrate that the mutation is a G to C transversion at position 5 of intron 1 of the beta- globin gene. Oligonucleotide probe surveys indicate that this variant accounted for all cases of beta thalassemia studied from Maewo. It is also common in coastal Papua New Guinea where haplotype and oligonucleotide probe data suggest that the molecular basis of beta thalassmia is more heterogeneous.  相似文献   
68.
Molecular assays are instrumental in the clinical management of viral hepatitis. During the past years, a wide variety of molecular assays have been developed and implemented. This considerably improved the understanding of the natural history and pathogenesis of Hepatitis B virus (HBV), Hepatitis C virus (HCV) or Hepatitis delta virus (HDV) hepatitis, but also caused uncertainties in the selection of the most appropriate assays for clinical requirements. Indeed, a rational choice and application of these assays requires adequate knowledge of the performance of the single test. Moreover, the choice of the most accurate assay for patients’ needs and physicians’ objectives, needs to be oriented to specific contexts, such as diagnosis, management or treatment. In the past, a hurdle in the routine use of assays for hepatitis viruses nucleic acid quantification was represented by the availability of only “home brew” methods which lacked standardization. Major improvement in addressing the use of molecular assays for viral hepatitis has been derived from recent standardization procedures that allowed a comparison between different tests after results were given as International Units. In addition, it should be reminded that, before getting into the market, molecular assays should be approved by European regulation authorities and validated using internationally recognized standards. A subsequent clinical validation should address the diagnostic accuracy of the assay. These proceedings have the aim of identifying which molecular tests, among those currently available, meet clinical requirements for each specific application.  相似文献   
69.
Several techniques are available today to access the bile ducts, all equally safe and effective. Since 1990, we have studied three groups of patients treated with different methods: the sequential endoscopic sphincterotomy + laparoscopic cholecystectomy, the single-stage laparoscopic approach, and the single laparoscopic-endoscopic approach. The results obtained in 127 patients to date suggest that one single-stage treatment is more convenient for the patient, while the combination of endoscopic sphincterotomy with laparoscopic cholecystectomy is preferable in terms of efficacy and safety.  相似文献   
70.
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