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排序方式: 共有7782条查询结果,搜索用时 31 毫秒
981.
Nuray Aslan A Mithat Bozdayi Hülya Cetinkaya Mustafa Sario?lu Cansel Türkay Hakan Bozkaya Selim Karayal?in Cihan Yurtaydin Ozden Uzunalimo?lu 《The Turkish journal of gastroenterology》2004,15(1):21-26
BACKGROUND/AIMS: A significant association between variations in amino acid sequences resides between 2209-2248 nucleotides of HCV non-structural 5A (NS5A) gene, and response to interferon treatment has been proposed. The aim of this study was to determine whether the amino acid sequence changes in ISDR could be correlated to response to alpha interferon treatment in Turkish patients infected with HCV genotypes 1b and 1a. METHODS: Thirty-nine patients with chronic C virus infection (35 and 4 patients with genotype 1b and 1a, respectively), receiving 3x3-5 MU of interferon a-2b for six months were included in the study. Following PCR amplification of the region from pre-treatment serum samples, the products were directly sequenced. The amino acid sequence of NS5A was compared with the published sequence for HCV-J (AA 2209-2248). Mutant type was defined as three or more amino acid mutations, and intermediate type as 1-3 amino acids in this region. Otherwise, they were defined as the wild type (no amino acid mutations). HCV RNA serum viremia levels were analyzed by branched DNA assay. RESULTS: Eighteen patients were responders (R; 46%), whereas 21 patients were non-responders (NR; 54%). Amino acid changes in both R and NR groups did not show significant difference. Intermediate or wild type strains were detected in both groups. CONCLUSIONS: In this study, we could not determine a significant association between number of amino acid changes in NS5A2209-2248 and response to interferon treatment. In the majority of the patients, it seems that amino acid sequences in this region are well conserved. 相似文献
982.
983.
Hakan N I?can Müfide Din?er Ali Gültan Orhan Meral Lale Taner-Sarisoy 《American journal of orthodontics and dentofacial orthopedics》2002,122(5):506-511
The aim of this study was to investigate the effects of the vertical chincap on mandibular morphology and also on the dentoalveolar structures in patients with high-angle open-bite malocclusions. We examined 35 children with high-angle skeletal Class I or II open-bite malocclusions. Eighteen subjects were selected as the treatment group, and 17 were the controls. Vertical chincaps, applying 400 g on each side from beneath the anterior part of the mandibular corpus in an upward direction, were used in the treatment group for 16 hours per day over a mean period of 9 months. We studied 70 lateral cephalograms taken before and after the treatment and the control periods. The changes of 7 linear and 8 angular parameters were evaluated statistically in both groups with paired and Student t tests, respectively. Eruption of the mandibular incisors, decrease of the ramal inclination, decrease of the mandibular plane, and increase of the overbite in the treatment group compared with the control group were found to be statistically significant. Intrusion of the first molars, decrease of the gonial angle, and increase of the mandibular corpus inclination in the treatment group were contrary to the results observed in the control group; these comparisons were also found to be statistically significant. It appears that the vertical chincap is effective in treating skeletal open bite and in decreasing the gonial angle and ramus/corpus relationship. 相似文献
984.
The present study is focused on spectrum analysis as a useful method of processing the PCG in order to obtain the frequency spectral distribution of normal heart sounds. Thirty normal subjects aged from 17 to 34 were studied. PCG was recorded on the fourth intercostal space at the left sternal border using a sound level meter coupled with a standard 6 ml cavity. The microphone had a linear response from 0.2 to 8,000 Hz. The signal was filtered with the standard B network according to the ANSI specifications and was registered on a four track FM tape recorder. A four channel analyzer with a microprocessor for off-line elaborations was used with 10 KHz sampling frequency. The PCG signal was triggered by a QRS detector on the R wave of the simultaneously recorded ECG. Fast Fourier transform was performed employing either a four channel analyzer with a microprocessor, or an A/D converter with a computer. Finally the results of the analysis were statistically elaborated. The described procedures permit to obtain a direct and exact tracing of the acoustic features of the heart, thus representing an attempt to come closer to the standardization and automatic analysis of the phonocardiographic technique. 相似文献
985.
The clinical and radiological features of one case of renal hydatid disease communicating with collecting system are described.
Introduction of hydatid elements into the renal pelvis due to rupture was accompanied by six episodes of renal colic. Although
the sonographic features of renal hydatid disease have been described extensively, direct demonstration by ultrasonography
of hydatid cyst ruptured into the renal pelvis has not, to our knowledge, been previously reported. The diagnosis has also
been confirmed at surgery.
Received 12 October 1995; Revision received 25 March 1996; Accepted 4 April 1996 相似文献
986.
Caloglu M Yurut-Caloglu V Altaner S Huseyinova G Unlu E Karagol H Uzal C 《Onkologie》2006,29(8-9):388-390
BACKGROUND: Oncocytic carcinoma is a rare tumor of major salivary glands. Despite being described 5 decades ago, not much is known about these rare tumors. Histochemical or electron microscopic confirmation of the oncocytic nature of the tumor cell is needed for differential diagnosis. The main treatment modality is surgery with or without adjuvant radiotherapy. Malignant oncocytomas have the potential risk of developing distant metastases and demand long term follow-up after therapy. CASE REPORT: A 58-year old man presented with a recurrent mass in the left parotid gland with a prior diagnosis of monomorphic adenoma in the same localization which had been treated by tumor excision in July 2002. Left superficial parotidectomy followed by radiotherapy into tumor bed and upper neck were carried out in September 2004. To date, he has had no evidence of recurrence for 14 months. CONCLUSION: For an accurate approach in the management of patients, oncocytic adenocarcinoma should be considered in the differential diagnosis of lesions of the parotid gland, most of which are benign. 相似文献
987.
Serum vascular endothelial growth factor (VEGF) and bcl-2 levels in advanced stage non-small cell lung cancer 总被引:6,自引:0,他引:6
The characteristic changes in cancer process are assumed to be genetic alterations about the imbalance of cell proliferation and apoptotic cell death. This study was conducted to determine the value of the circulating vascular endothelial growth factor (VEGF) and Bcl-2 in patients with advanced stage non-small cell lung cancer (NSCLC). These serum factors were measured of 52 NSCLC patients pathologically verified on before and after chemotherapy in comparison with 16 healthy controls by using ELISA method. Both of the serum levels of VEGF (p = 0.015) and Bcl-2 (p < 0.001) were increased significantly in NSCLC patients compared with the healthy controls. No statistically significant relationships between investigated elevated serum parameters and various characteristics of patients and disease such as stage and tumor burden were determined. Likewise, we also found no correlation between serum VEGF and Bcl-2. Cytotoxic therapy of patients was accompanied by unchanged serum levels of serum factors. The median survival of all patients was 27 weeks and one-year survival rate was 22.4 percent. With the median serum levels as the cut-off value, patients were divided into high- and low-serum parameter groups. While we found that patients' performance status (p < 0.0001), serum LDH level (p = 0.0002), response to chemotherapy (p = 0.0023), and stage of the disease (p = 0.0085) were prognostic factors for survival, serum VEGF (p = 0.48) and Bcl-2 (p = 0.91) levels were determined as ineffective on survival in patients with advanced NSCLC. In conclusion, our data suggest that these serum factors, VEGF and Bcl-2, are useful diagnostic factors, not predictive and prognostic markers for overall survival in advanced NSCLC patients. 相似文献
988.
Angiogenesis is essential for tumor progression and metastasis; however, the angiogenesis regulators that are biologically relevant for melanoma are still unknown. In this study, we analyzed the circulating serum levels of potent angiogenic factors, including vascular endothelial growth factor (VEGF), angiogenin, transforming growth factor-beta1 and VEGF receptors, VEGFR1 and VEGFR2, in human melanoma patients. One hundred and fourteen patients with histopathologically verified cutaneous melanoma at different stages and 30 healthy controls were investigated. Serum levels of angiogenic factors and VEGF receptors were quantitatively analyzed by solid-phase enzyme-linked immunosorbent assay. The age of the patients (61 men and 53 women) ranged from 18 to 80 years; median age was 51 years. Serum transforming growth factor-beta1 (P < 0.001), VEGF (P = 0.006) and VEGFR1 (P = 0.007) levels were significantly higher in patients with melanoma than in the control group. No significant differences, however, exist in the serum angiogenin and VEGFR2 levels between melanoma patients and the controls. The positive correlations of elevated serum levels of transforming growth factor-beta1, VEGF and VEGFR1 with advanced stages of disease were found. Significant relationship was found only between serum levels of VEGF and VEGFR2. Elevated serum transforming growth factor-beta1 (P < 0.001) and VEGF levels (P = 0.0012) were found to be poor prognostic factors. Serum level of angiogenin and VEGF receptors, however, had no effect on survival. Our data suggest that the angiogenic serum factors, including VEGF, transforming growth factor-beta1 and VEGFR1, but not angiogenin and VEGFR2 were increased in melanoma patients, especially associated with advanced disease stages. The mechanism of VEGF regulation of angiogenesis may in part be due to enhanced proliferation of VEGFRs, especially VEGFR1. 相似文献
989.
Akarsu E Buyukhatipoglu H Aktaran S Geyik R 《The Mount Sinai journal of medicine, New York》2006,73(7):1021-1023
We present an unusual case of a drug-related hemorrhagic diathesis. One month prior to admission, the patient was diagnosed at another medical center as having Graves' disease and propylthiouracil therapy (PTU) was initiated. Since clinical recovery was not achieved, the PTU was quickly increased to an unconventional daily dose of 1,000 mg. The patient was referred to our hospital because of spontaneous epistaxis, multiple ecchymoses and prolonged prothrombin time (PT) and activated partial thromboplastin time (aPTT), which developed soon after the increase in PTU dose. Drug-related hemorrhagic diathesis was considered, after other possible causes had been eliminated. To the best of our knowledge, this is the first reported case of spontaneous hemorrhage due to PTU use. 相似文献
990.
Cam H Griesmann H Beitzinger M Hofmann L Beinoraviciute-Kellner R Sauer M Hüttinger-Kirchhof N Oswald C Friedl P Gattenlöhner S Burek C Rosenwald A Stiewe T 《Cancer cell》2006,10(4):281-293
The p53 family comprises the tumor suppressor p53 and the structural homologs p63 and p73. How the three family members cooperate in tumor suppression remains unclear. Here, we report different but complementary functions of the individual members for regulating retinoblastoma protein (RB) function during myogenic differentiation. Whereas p53 transactivates the retinoblastoma gene, p63 and p73 induce the cyclin-dependent kinase inhibitor p57 to maintain RB in an active, hypophosphorylated state. DeltaNp73 inhibits these functions of the p53 family in differentiation control, prevents myogenic differentiation, and enables cooperating oncogenes to transform myoblasts to tumorigenicity. DeltaNp73 is frequently overexpressed in rhabdomyosarcoma and essential for tumor progression in vivo. These findings establish differentiation control as a key tumor suppressor activity of the p53 family. 相似文献