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101.
102.
目的:探讨人乳头瘤病毒(HPV)E6/E7mRNA检测用于未明确诊断意义的不典型鳞状上皮细胞(ASCUS)诊断结果的判定价值。方法:对160例薄层液基细胞学检查诊断为ASCUS者进行HPV E6/E7mRNA和高危型HPV(HR-HPV)DNA检测,结合病理学诊断资料进行统计学分析。结果:160例中病理结果为宫颈上皮内瘤变Ⅱ级(CINⅡ)及以上级别者的HPV E6/E7mRNA阳性率明显高于CINⅡ以下级别者,差异有统计学意义(P0.05),但与HR-HPV DNA检测结果无统计学差异。HPV E6/E7 mRNA检测CINII及以上级别的灵敏度(69.2%)与HR-HPV DNA检测相比无统计学差异(P0.05);特异度(73.9%)高于HR-HPV DNA检测(61.9%),差异有统计学意义(P0.05)。结论:HPV E6/E7 mRNA检测可作为ASCUS者是否需要进行阴道镜检查的一项指标依据。 相似文献
103.
Guido Cimoli Monica Valenti Elvira Noviello Silvio Parodi Alessandra Mazzoni Elisabetta Rovini Fabio De Sessa Patrizia Russo 《Journal of cancer research and clinical oncology》1995,121(3):155-163
Human ovarian cancer cells A2780, selected for resistance to doxorubicin (A2780-DX3), are crossresistant to various other topoisomerase-II-targeted drugs but not to vinblastine. The parental cell line was very sensitive to doxorubicin-, mitoxantrone- or etoposide (VP16)-induced DNA single-strand breaks, under deproteinizing conditions. In contrast, little or no DNA strand breakage was seen in resistant A2780-DX3 cells, even at very high concentrations, indicating a good correlation, with cytotoxicity. No significant alterations in cellular drug uptake were observed in DX3 cells. Further studies showed that the nuclei isolated from resistant cells were also resistant to mitoxantroneor VP16-induced single-strand breaks, indicating that nuclear modifications in resistant cells are responsible for this resistance. Catalytic activity in crude nuclear extracts from wild-type and DX3 cells was almost equal. However, an assay that specifically measures generation of 5-protein-linked breaks in32P-labeled 3 DNA revealed that, DNA cleavage activity in nuclear extract from the DX3 cell line is profoundly resistant to a stimulation by VP16. These data indicate that stimulation of topoisomerase-II-mediated DNA cleavage is responsible for topoisomerase-II-targeted drugcytotoxicity rather than loss of normal topoisomerase catalytic function. These data support the hypothesis that A2780-DX3 cells display an atypical multidrug resistance.Abbreviations
MDR
multidrug resistance
-
SSB
Single-strand break 相似文献
104.
105.
Intradural petrous bone drilling has become a widespread practice, providing extended exposure in the removal of cerebellopontine angle (CPA) or petroclival tumors. Adjacent neurovascular structures are at risk, however, when drilling is performed in this deep and narrow area. Hence, this study evaluates the use of Piezosurgery (PS) as a non-rotating tool for selective bone cutting in CPA surgery.A Piezosurgery® device was used in 36 patients who underwent microsurgery for extra-axial CPA or petroclival tumors in our Neurosurgical Department between 2013 and 2019. The clinical and radiological data were retrospectively analyzed. The use of PS was evaluated with respect to the intraoperative applicability and limitations as well as efficacy and safety of the procedure.Piezosurgical petrous bone cutting was successfully performed in the removal of meningiomas or extra-axial metastases arising from the dura of the petroclival region (21 patients) or petrous bone (15 patients). PS proved to be very helpful in the deep and narrow CPA region, considerably reducing the surgeon’s distress toward bone removal in close proximity to cranial nerves and vessels in comparison to common rotating drills. The use of PS was safe without injuries to neurovascular structures. Gross total resection was achieved in 67% of petroclival and 100% of petrous bone tumors.Piezosurgery proved to be an effective and safe method for selective petrous bone cutting in CPA surgery avoiding rotating power and associated risks. This technique can particularly be recommended for bone cutting in close vicinity to critical neurovascular structures. 相似文献
106.
《Indian journal of medical microbiology》2021,39(1):41-47
PurposeTo describe demographics, risk factors, antibiotic susceptibility, management and outcomes of ocular infections caused by non-tuberculous mycobacteria (NTM).MethodsA retrospective review of medical case records and microbiology records of patients with ocular infections that were culture positive for non-tuberculous Mycobacteria from January 2014 to December 2018 was done. Antibiotic susceptibility profile was done based on the CLSI guidelines. Laboratory diagnosis for the NTM Species was done by conventional microbiological methods. The species identification was done for stored isolated utilizing polymerase chain reaction targeting 16S rDNA and rpoB gene, followed by DNA sequencing and phylogenetic analysis.ResultsTwenty patients with NTM ocular infections were identified during the study period. A majority of cases presented as 12 infectious keratitis (60%) and three suture-related corneal infiltrates (15%). Common risk factors were history of trauma in 9 (45%) patients and history of ocular surgery in 5 (25%) patients. Patients were treated with combination of amikacin and flouroquinolones/chloramphenicol (70%) and surgical interventions were performed in 25% cases. Only twelve isolates were stored and ten isolates were identified as the M. abscessus subsp. abscessus and two isolates as M. abscessus subsp. massiliense by sequencing and phylogenetic analysis. Majority of the NTM were sensitive to amikacin (75%) followed by moxifloxacin, ciprofloxacin, cephotaxime and tobramycin (35%).ConclusionHigh degree of clinical suspicion, multidrug antibiotic therapy and timely surgical intervention in patients with NTM infections, are advised for better clinical outcomes. Prior ocular trauma, prior ocular surgery and presence of biomaterials were the major predisposing factors. Earlier surgical intervention in cases where abscesses or biomaterials are involved, is necessary for rapid recovery. 相似文献
107.
Karin Ashizawa Kanako Ogura Shunsuke Nagase Asumi Sakaguchi Joji Tokugawa Makoto Hishii Masaharu Fukunaga Takanori Hirose Toshiharu Matsumoto 《Pathology international》2021,71(10):697-706
An intracranial collision tumor is a rare lesion composed of two histologically different neoplasms in the same anatomic location. Even more rare is the collision tumor of a solitary fibrous tumor/hemangiopericytoma (SFT/HPC) and meningioma. The patient was a 46-year-old woman who had a 40 × 35 × 30-mm mass in the vermis of the cerebellum. Histologically, the mass consisted of two different components. One component showed the morphology of meningioma (World Health Organization (WHO) grade I), and the other component exhibited small round cell proliferation with hypercellular density, which was revealed to be SFT/HPC (WHO grade III) based on STAT6 immunohistochemistry. STAT6 showed completely different immunohistochemistry results in these two components (nuclear-negative in meningioma and nuclear-positive in SFT/HPC). Since these two neoplasms are associated with different prognoses, they should be distinguished from each other. When meningioma and an SFT/HPC-like lesion are identified morphologically, it is important to recognize the presence of such a collision tumor composed of meningioma and SFT/HPC, and identify the SFT/HPC component by employing STAT6 immunohistochemistry. 相似文献
108.
109.
?lkay ?aml?da? Yang-Je Cho Mina Park Seung Koo Lee 《Korean journal of radiology》2015,16(5):1104-1108
Posterior reversible encephalopathy syndrome (PRES) is usually a reversible clinical and radiological entity associated with typical features on brain MR or CT imaging. However, the not-so-uncommon atypical radiological presentations of the condition are also present and they may go unrecognised as they are confused with other conditions. Here, we report a very rare case of atypical, unilateral PRES in a 49-year-old uremic, post-transplant female patient who presented with seizures. Initial MRI showed high-grade occlusion of the left middle cerebral artery (MCA) and lesions suggestive of subacute infarction in the ipsilateral frontotemporoparietal lobe. Patient symptoms had resolved a day after the onset without any specific treatment but early follow-up CT findings suggested hemorrhagic transformation. Follow-up MRI performed 2 years later showed complete disappearence of the lesions and persisting MCA occlusion. 相似文献
110.
目的 探讨颅内不典型脑膜瘤的MRI表现,分析其误诊原因。方法 回顾性分析9例经手术病理证实的不典型脑膜瘤的MRI表现、病理及临床资料。结果 9例肿瘤位于大脑凸面4例,大脑镰旁2例,幕下横窦旁、桥小脑角区及桥延交界区各1例。本组误诊为胶质瘤4例、转移瘤2例、神经鞘瘤2例、海绵状血管瘤1例。结论 颅内不典型脑膜瘤MRI表现多样,在观察肿瘤基本信号特征的基础上进一步分析肿瘤与临近组织之间的关系、结合肿瘤的发病部位、注重少见病理亚型脑膜瘤的MRI信号特点有助于提高不典型脑膜瘤的诊断准确率。 相似文献