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The integration sites of human papillomavirus (HPV) DNA within the cervical carcinoma cell line C4-I and a primary cervical tumor were mapped by in situ hybridization. Cloned cellular sequences flanking the integrated viral DNA were used as probes. For the cell line, the viral integration site was mapped to chromosome region 8q21-q22.3, while in the primary tumor chromosome band 3p21 was the target for integration. The HPV DNA integration appears to occur in the vicinity of fragile sites, oncogenes, and chromosome breakpoints that are characteristic of hematologic malignancies and solid tumors. The integration of HPV may thus promote chromosome changes in cancer cells.  相似文献   
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Velo-cardio-facial syndrome (VCFS) and DiGeorge syndrome (DGS) are developmental disorders characterized by a spectrum of phenotypes including velopharyngeal insufficiency, conotruncal heart defects and facial dysmorphology among others. Eighty to eighty-five percent of VCFS/DGS patients are hemizygous for a portion of chromosome 22. It is likely that the genes encoded by this region play a role in the etiology of the phenotypes associated with the disorders. Using a cDNA selection protocol, we isolated a novel clathrin heavy chain cDNA (CLTD) from the VCFS/DGS minimally deleted interval. The cDNA encodes a protein of 1638 amino acids. CLTD shares significant homology, but is not identical to the ubiquitously expressed clathrin heavy chain gene. The CLTD gene also shows a unique pattern of expression, having its maximal level of expression in skeletal muscle. Velopharyngeal insufficiency and muscle weakness are common features of VCFS patients. Based on the location and expression pattern of CLTD, we suggest hemizygosity at this locus may play a role in the etiology of one of the VCFS-associated phenotypes.   相似文献   
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Morphologic features of Burkitt lymphoma (BL) and diffuse large B-cell lymphoma (DLBCL) overlap. No single phenotypic marker or molecular abnormality is pathognomonic. We tested a panel of 8 germinal center (GC) and activated B-cell (ABC) markers for their ability to separate BL and DLBCL. We diagnosed 16 BL and 39 DLBCL cases from 21 patients with AIDS and 34 without AIDS based on traditional morphologic criteria, Ki-67 proliferative index, and c-myc rearrangement (fluorescence in situ hybridization). After immunohistochemically staining tissue microarrays of BL and DLBCL for markers of GC (bcl-6, CD10, cyclin H) and ABC (MUM1, CD138, PAK1, CD44, bcl-2), we scored each case for the percentage of positive cells. Hierarchical clustering yielded 2 major clusters significantly associated with morphologic diagnosis (P < .001). For comparison, we plotted the sum of the GC scores and ABC scores for each case as x and y data points. This revealed a high-GC/low-ABC group and a low-GC/high-ABC group that were associated significantly with morphologic diagnosis (P < .001). Protein expression of multiple GC and ABC markers can separate BL and DLBCL.  相似文献   
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One hundred and forty-four patients with apparently benign gastric ulcer were endoscopically followed up in order to evaluate the outcome of the lesion. Particular attention was given to: (a) detect possible delay in diagnosing gastric cancer; (b) ascertain the frequency of association with epithelial dysplasia; (c) establish the role of markers, such as serum pepsinogen group I (PGI), and gastric juice CEA in predicting gastric ulcer evolution. Endoscopic and bioptic check-ups were carried out during the first year at 3, 6 and 12 months after endoscopic healing of the ulcer, and then at every symptomatic recurrence. Ten patients (6.9%) were found to present histological evidence of malignancy (within 3 months in six cases, between 6 and 12 months in three cases, and after 41 months in the rest). Four cases were early gastric cancers, and six had shown dysplastic changes of the mucosa at the edge or scar of the ulcer. Serum PGI levels were not significantly different in gastric cancer patients, while gastric juice CEA levels were sharply increased compared to those of gastric ulcer patients: nine out of ten patients had values above normal range. These data suggest that: (a) there may be some delay in diagnosing gastric carcinoma, and gastric ulcer patients should be controlled routinely more than once; (b) the presence of dysplasia indicates the need for prolonged follow-up, because of the high risk of association with or evolution into gastric cancer, and because of the higher number of early gastric cancer detections that this protocol allows; (c) further support in monitoring patients "at risk" may be afforded by gastric juice CEA determination.  相似文献   
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Neurosurgical Review - Chordoma is a rare slow-growing neoplastic bone lesion. However, they show an invasive local growth and high recurrence rate, leading to an overall survival rate of 65% at 5...  相似文献   
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BACKGROUND/AIMS: Short-term ranitidine bismuth citrate-based triple regimens have been shown to be effective for the eradication of H. pylori. We investigated the efficacy of an eradicating therapy including ranitidine bismuth citrate, low-dose clarithromycin and tinidazole, administered for only 6 days. METHODOLOGY: Forty-five consecutive patients, who underwent gastroscopy for symptoms and were found to be H. pylori-positive, were recruited. They received ranitidine bismuth citrate 400 mg b.i.d. plus clarithromycin 250 mg b.i.d. plus tinidazole 500 mg b.i.d., given for 6 days. The medications given in twice daily doses were taken after meals with an interval of 12 h. The H. pylori status was evaluated by means of histology and rapid urease test on admission, and by 13C-urea breath test alone 8 weeks after treatment. RESULTS: All 45 enrolled patients completed the study. Thirty-nine of 45 patients returned H. pylori-negative (both per protocol and intention-to-treat analysis = 87%; 95% confidence interval = from 73-95%), while 6 of 45 were still H. pylori-positive (13%). Slight or mild side effects occurred in 5/45 patients (11%). CONCLUSIONS: Ranitidine bismuth citrate-based triple therapy, containing low-dose clarithromycin and tinidazole, given for only 6 days, yielded high eradication rates with modest side effects. Regimens based on ranitidine bismuth citrate plus two antibiotics at low dosages, administered for less than 7 days, constitute highly promising strategies for eradication of H. pylori.  相似文献   
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BACKGROUND AND PURPOSE:Tentorial dural arteriovenous fistulas are characterized by a high hemorrhagic risk. We evaluated trends in outcomes and management of tentorial dural arteriovenous fistulas and performed a meta-analysis evaluating clinical and angiographic outcomes by treatment technique.MATERIALS AND METHODS:We performed a comprehensive literature search for studies on surgical and endovascular treatment of tentorial dural arteriovenous fistulas. We compared the proportion of patients undergoing endovascular, surgical, and combined endovascular/surgical management; the proportion of patients presenting with ruptured tentorial dural arteriovenous fistulas; and proportion of patients with good neurologic outcome across 3 time periods: 1980–1995, 1996–2005, and 2006–2014. We performed a random-effects meta-analysis, evaluating the rates of occlusion, long-term good neurologic outcome, perioperative morbidity, and resolution of symptoms for the 3 treatment modalities.RESULTS:Twenty-nine studies with 274 patients were included. The proportion of patients treated with surgical treatment alone decreased from 38.7% to 20.4% between 1980–1995 and 2006–2014. The proportion of patients treated with endovascular therapy alone increased from 16.1% to 48.0%. The proportion of patients presenting with ruptured tentorial dural arteriovenous fistulas decreased from 64.4% to 43.6%. The rate of good neurologic outcome increased from 80.7% to 92.9%. Complete occlusion rates were highest for patients receiving multimodality treatment (84.0%; 95% CI, 72.0%–91.0%) and lowest for endovascular treatment (71.0%; 95% CI, 56.0%–83.0%; P < .01). Long-term good neurologic outcome was highest in the endovascular group (89.0%; 95% CI, 80.0%–95.0%) and lowest for the surgical group (73.0%; 95% CI, 51.0%–87.0%; P = .03).CONCLUSIONS:Patients with tentorial dural arteriovenous fistulas are increasingly presenting with unruptured lesions, being treated endovascularly, and experiencing higher rates of good neurologic outcomes. Endovascular treatment was associated with superior neurologic outcomes but lower occlusion rates.

Intracranial dural arteriovenous fistulas (DAVFs) are abnormal direct shunts between the dural arteries and dural veins.1 The shunt is located in the intracranial dura mater with venous drainage directed to the dural venous sinuses or cortical veins. Dural arteriovenous fistulas account for 10%–15% of all intracranial vascular shunts.1,2 Tentorial dural arteriovenous fistulas (TDAVFs) constitute only 4% of DAVFs and are characterized by a high hemorrhagic risk. Because of this, these lesions are treated aggressively on diagnosis.35Traditionally, surgical resection was the only treatment available for these lesions. However, endovascular embolization, either alone or in combination with surgery, is increasingly used.6 Stereotactic radiosurgery is also increasingly used as an adjunct to surgical and endovascular treatment.7 We performed a systematic review of the literature on surgical and endovascular treatment of TDAVFs from 1980 to 2014. The purpose of our study was the following: 1) to determine whether there was a shift from primarily surgical treatments to endovascular and multimodality treatment during this time period, 2) to determine whether the proportion of patients presenting with ruptured TDAVFs during this time period has changed, 3) to determine whether the rate of good neurologic outcome has changed, and 4) to evaluate clinical and angiographic outcomes in endovascular, surgical, and combined treatments by performing a random-effects meta-analysis.  相似文献   
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The human leukemia cell line K562, derived from a patient with Philadelphia chromosome-positive chronic myelogenous leukemia, contains amplified c-abl oncogenes and unrearranged C lambda genes. Using in situ hybridization techniques, we have determined that the amplified c-abl and C lambda DNA sequences of K562 cells are both located on the same abnormal acrocentric marker chromosome, which may represent an altered Philadelphia chromosome.  相似文献   
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