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82.

Background  

Although studies comparing the surgical treatment of gastric carcinoma in Japan and Western industrialized countries have revealed differing survival rates, no studies to date have been performed comparing Western and Eastern Europe. This study aimed to compare demographics and surgical practice as well as the related prognostic impact on gastric cancer patients treated in Poland and Germany.  相似文献   
83.
Cladribine (2-chlorodeoxyadenosine, 2-CdA) treatment-associated infections may shorten potentially long-term survival in hairy cell leukemia (HCL). In search of the optimal mode of 2-CdA administration, 132 patients with untreated HCL were randomized to receive either standard 5-day 2-CdA protocol or a novel schedule of 6 weekly 2-CdA infusions suggested to be less toxic. Analysis of treatment response confirmed similar complete remission rates, overall response rates, progression-free survival, and overall survival in both 2-CdA protocols. However, we did not observe lower toxicity in the weekly schedule. Of special interest, no significant differences were found in the rate of grade 3/4 infections (18% for daily and 26% for weekly protocol, difference –8.2%; 95% confidence interval [CI] –23.2% to 6.9%; P = .28) and the rate of septic deaths (3% for daily and 2% for weekly protocol, difference 1.4%; 95% CI –4.3% to 7.0%; P = .64). In conclusion, HCL treatment with weekly 2-CdA infusions is equally effective but no safer than the standard 5-day 2-CdA protocol.   相似文献   
84.
Alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors are one of the important receptor classes involved in glutamate-mediated excitotoxicity. Although small molecule antagonists of this receptor have been shown to have neuroprotective properties, their low solubilities pose severe side effects in clinical trials. Here we have used the SELEX method to obtain water-soluble nuclease-resistant RNA ligands that bind to the agonist binding site of AMPA receptors. Using whole-cell current recordings, we have characterized the functional consequences of a representative aptamer from this class and show that it is a competitive antagonist of AMPA receptors and in the concentration range where it acts as an inhibitor of the AMPA receptor the RNA has no effect on the GluR6 homomeric kainate receptors. Additionally, using a fluorescence resonance energy transfer (FRET) probe, we show that this RNA ligand stabilizes the open cleft conformation of the ligand binding domain, consistent with the known structures of small antagonist-bound states of the soluble domain of this protein. Finally, using rat primary cortical neurons, we show that this RNA ligand significantly reduces neurotoxicity associated with oxygen glucose deprivation. The water-soluble and antagonistic properties of this aptamer coupled with its neuroprotective properties make it an excellent candidate for potential use in diseases or pathological conditions involving glutamate-mediated excitotoxicity.  相似文献   
85.
The role of tissue characterization by intravascular ultrasound (IVUS) imaging of the aortic wall has not been well established. The artificial neural networks (ANNs) are a promising tool for image classification. The aim of the study was to assess the texture correlation between matching IVUS and histologic images of the aortic wall. The computer-based discrimination of pathology within the data sets was also evaluated. In vitro IVUS images and histologic sections from 36 aortic segments were compared using texture parameters that produced the best correlation or the highest discriminative value. The images were classified as normal or abnormal with variable degrees of pathology. Tissue characterization was performed by a nearest neighbor classifier, linear discriminant analysis (LDA) and the ANN-based approach. Good agreement was observed between IVUS and the histologic reference with a correlation coefficient of r = 0.89, r = 0.76 and r = 0.71 for the three most successful texture parameters. The ANN-based approach was the most effective in discriminant analysis, with a correct classification rate of 87.5% for histologic images and 79.2% for IVUS data. The study shows that ANNs are a potentially effective tool for assessment of IVUS aortic images.  相似文献   
86.
BACKGROUND: Traumatic patellar dislocation (TPD) may be associated with other injuries requiring additional treatment. The superficial localization of the knee extensor apparatus and knee articular cartilage make them accessible to sonographic evaluation (ultrasonography [USG]). PURPOSE OF THE STUDY: Prospective analysis of the value of USG in TPD. METHODS: In 21 patients, 22 knees were examined by USG after clinical and routine radiographic evaluations. Based on USG findings, operative or nonoperative treatment was done (15 and 7 cases, respectively). RESULTS: In 17 knees, lesions of the medial patellofemoral ligament (MPFL) fibers were visible. In 16 knees, avulsion fractures of the patellar insertion of the MPFL were identified. Injuries of the femoral attachment of the MPFL or intramuscular hematoma of the vastus medialis obliquus (VMO) were present in 7 knees. Eleven osteochondral loose bodies and 1 nondisplaced osteochondral fracture were detected in 11 knees. Corresponding osteochondral lesions were localized in all cases. An osteochondral loose body that was identified by USG was confirmed intraoperatively or by computed tomographic scan in 91.6%, the osteochondral lesion localization in 81.8%, and avulsion fracture of the patellar attachment of the MPFL in 100% of knees. Overall, the USG findings were confirmed by these methods in 88.2% of knees. CONCLUSIONS: Ultrasonography is highly efficient in determining the extent of injuries after TPD in adolescents. Ultrasonography allows visualization of loose bodies, localization of osteochondral lesions, and, using a dynamic modification, allows precise assessment of the functional status of the MPFL. LEVEL OF EVIDENCE: II.  相似文献   
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Human papillomaviruses infect epithelia but little is known about the nature of cell surface receptors interacting with the viral particles. It has been proposed that glycosaminoglycans and integrins may be involved in the attachment process. In the present study, the putative interactions of virus-like particles of human papillomavirus type 11 (HPV11), which present a tropism for nasopharyngeal epithelia, with olfactory and taste receptors expressed in the human lingual epithelium were studied. The L1 protein of HPV11 was produced in insect cells. The presence of L1 virus-like particles was analyzed by ELISA using monoclonal antibodies specific for full-size particles and by electron microscopy. Using immunofluorescence, it was observed that virus-like particles interacted with taste buds from murine tongue, with the tagged human olfactory receptor hJCG5 expressed in HEK-293 but not with the tagged taste receptor hT2R4. This therefore suggests that hJCG5 may be involved in the adsorption process of HPV11 to lingual epithelium serving as a so-called "adsorption-adhesive molecule."  相似文献   
90.
Since the vegetarian diet lacks the substrate for pancreatic elastase-1 as an enzyme, a decreased secretion of this enzyme could be expected. We aimed therefore to assess the changes of exocrine pancreatic secretion in a prospective way in a group of healthy omnivores who modified their diet by abstaining from meat for 1 month. Twenty healthy omnivores (fourteen females and six males) were used in the study. The nutrient intake was assessed for 7 d before commencing the study (omnivore diet) and after 1 month of dietary modification (modified diet; meat excluded). Similarly, the faecal output of pancreatic enzymes (elastase-1, chymotrypsin and lipase) was assessed before and 1 month after the period of dietary modification. Statistical differences between two points of the assessment (paired data) were calculated with the use of the Wilcoxon rank test. The relationship between the changes of faecal enzyme output and the changes in nutrient intake was assessed using multiple regression analysis. The dietary changes resulted in statistically significant decrease of faecal elastase-1 output (P < 0.05), whereas for chymotrypsin and lipase no changes were observed. No significant change in stool weight was recorded. No statistically significant correlation between changes in energy and nutrient consumption and changes in faecal output of pancreatic enzymes has been found. It was concluded that the exclusion of meat from the diet for a 1-month period results in significant changes in pancreatic secretion with a selective decrease of elastase-1 output. However, the underlying factor remains unclear.  相似文献   
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