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11.
Sumer H  Craig JM  Sibson M  Choo KH 《Genome research》2003,13(7):1737-1743
Human neocentromeres are fully functional centromeres that arise at previously noncentromeric regions of the genome. We have tested a rapid procedure of genomic array analysis of chromosome scaffold/matrix attachment regions (S/MARs), involving the isolation of S/MAR DNA and hybridization of this DNA to a genomic BAC/PAC array. Using this procedure, we have defined a 2.5-Mb domain of S/MAR-enriched chromatin that fully encompasses a previously mapped centromere protein-A (CENP-A)-associated domain at a human neocentromere. We have independently verified this procedure using a previously established fluorescence in situ hybridization method on salt-treated metaphase chromosomes. In silico sequence analysis of the S/MAR-enriched and surrounding regions has revealed no outstanding sequence-related predisposition. This study defines the S/MAR-enriched domain of a higher eukaryotic centromere and provides a method that has broad application for the mapping of S/MAR attachment sites over large genomic regions or throughout a genome.  相似文献   
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Primary hemangiopericytoma of the rib is extremely rare and only a few cases have been reported. A 62-yr-old man presented with an aching chest pain and dyspnea. Thoracic computed tomography revealed a homogenous mass expanding the right seventh rib. A diagnosis of hemangiopericytoma was established by percutaneous needle biopsy. Preoperative embolization of the feeding vessels of the tumor was performed in order to prevent perioperative bleeding. There was no significant bleeding during the surgery, where complete resection of the tumor with 7th to 9th ribs with a surgical margin of 5 cm was performed. Postoperative course was uneventful and there has been no recurrence for thirteen months. To our knowledge, there has been no report to apply a preoperative embolization of a primary hemangiopericytoma of the rib.  相似文献   
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Because slime-forming microorganisms are the major causative agents of graft infections, we aimed to investigate bacterial adherence in slime-forming and nonslime-forming Staphylococcus aureus and to determine the role of neuraminidase (NANase) on adherence to gelatin-impregnated polyester fiber graft fabric. An in vitro model was developed to quantitatively measure bacterial adherence to the surface of the graft. The grafts were divided into two groups – those colonized with slime-forming S. aureus and those colonized with nonslime-forming S. aureus. The grafts were put into sterile tubes and human plasma was instilled and incubated at 37°C to perform fibrin deposition on the grafts. After 48 h of incubation, grafts were drained and inoculated with slime-forming or nonslime-forming S. aureus in triptic soy broth in the presence or absence of NANase. Following 36 h of incubation at 36°C, grafts were vortexed and cultured to perform a colony count. Bacterial counts were expressed as total colony-forming units per square centimeter of graft. Slime-forming S. aureus had greater affinity with the graft compared with nonslime-forming S. aureus (P < 0.05). The adherence of slime-forming S. aureus was impaired by NANase treatment (P < 0.001) but NANase treatment of nonslime-forming S. aureus did not change the adherence to the graft (P > 0.05). These results show that slime plays an important role in the pathogenesis of vascular graft infection. Adherence of slime-forming S. aureus can be decreased by NANase treatment. This may have implications for the development of neuraminidase-embedded vascular grafts to diminish biomaterial-related infections.  相似文献   
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Pneumoconiosis was diagnosed by open lung biopsy in two dental technicians who had interstitial lung disease. Mineralogical analysis was performed to investigate the origin of the dust that had been inhaled. A marked accumulation of silicon and phosphorus was found in both cases. The hard metals chromium and cobalt were also found. Dental technician's pneumoconiosis is a complex pneumoconiosis in which such dust and hard metals may play a role.  相似文献   
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Pain during sexual activity and ejaculation are the unspoken long-term complications of groin hernia repair. Laparoscopic surgical techniques are associated with decreased post-operative pain and earlier return to daily activities, but its effect on these complications is unclear. This study aims to investigate the effect of transabdominal preperitoneal repair (TAPP) on de-novo pain during sexual intercourse and ejaculation and to compare with open repair. For this reason, two groups were determined according to the surgical technique: the Lichtenstein repair and the TAPP groups and a questionnaire was sent to the patients a minimum of 6 months following the surgery. A total of 317 patients included, as 115 in TAPP and 202 in Lichtenstein repair group. No significant difference was observed concerning pre-operative pain during sexual activity and ejaculation in both groups (p = .75, p = .56). Following the surgery, the number of patients experiencing painful sexual activity was significantly higher in the Lichtenstein repair group compared to the TAPP group (19.3% vs. 11.3%, respectively, p = .03). The post-operative painful ejaculation rate was also significantly lower for the TAPP group (p = .04). The lower rates of post-operative dysejaculation and pain during sexual activity can be achieved with the advantage of laparoscopic surgery.  相似文献   
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This study aims to synthesize and characterize an economical and ecological adsorbent with high adsorption capacity. For this purpose, the peanut shells (Pistacia vera L.) were modified chemically. After the synthesis of activated carbon (AC), the optimum conditions for enrichment steps were performed using parameters: pH and contact time for uranium in the model solutions. The measurements were carried out by inductively coupled plasma-mass spectrometry (ICP-MS). From the shapes of the BET isotherms, the AC obtained exhibits type I. The study indicated that the surface area and total pore volume of the AC were found to be 679.9 m2 g−1 and 0.31 cc g−1, respectively. The adsorption capacity was found to be 260 mg g−1. The optimum pH was found to be 6.0 for enrichment using the AC obtained by sulfuric acid as a chemical-modifier. The optimized method was applied to enrichment of U at ppb levels in the model solutions.

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18.
Neoplastic conversion induced in rat liver by diethylnitrosamine(DEN) was quantified by measuring preneoplastic and neoplasticlesions over a 34 week period in the beginning of which thecarcinogen was given at three dose levels and two dose ratesfor the first 10 weeks, after which animals were maintainedfor 24 weeks with either no further exposure or were fed phenobarbital(PB) to promote neoplastic development of cells converted byDEN. DEN was injected s.c. inmale F344 rats at weekly or biweeklyintervals for total doses of 1, 2 or 4 mmol/kg body wt and thenthe rats were maintained on basal diet alone or diet containing0.05% PB. At the end of exposure, DEN had produced a dose-relateddecrease in centrilobular glutamine synthetase-expressing (GS+)hepatocytes which is indicative of mild cytotoxicity. All dosesinduced foci that were  相似文献   
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BACKGROUND: Cauda equina syndrome occurring as a result of spontaneous spinal subarachnoid hemorrhage (SAH) from a spinal tumor is reported to be rare. CASE DESCRIPTION: A 28-year-old woman presented at our clinic with a history of severe back pain for 10 days, progressive paraparesis, and urinary retention. Her physical examination revealed a mass located intradurally at the level of L1-2 and a massive SAH. An L1-L2, laminectomy and a hemilaminectomy from D9 to D12 were performed and the SAH was evacuated and the cord was decompressed. CONCLUSION: At the first year follow-up, her restricted dorsal and plantar flexion continued. Post-gadolinium magnetic resonance imaging revealed no mass.  相似文献   
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