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Compartments of the adult parasellar region   总被引:1,自引:0,他引:1  
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An implantable cardioverter defibrillator was placed into a sub-pectoral pocket via the incision for cephalic venotomy during implantation of a nonthoracotomy lead system. The approach obviated another incision and subcutaneous tunneling of the leads. There were no perioperative complications and after 6 months of follow-up, the patient continues to tolerate the device satisfactorily.  相似文献   
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Trisomy 3 represents the most frequent and consistent chromosomal abnormality characterizing the recently defined entity marginal zone B-cell lymphoma (MZBCL). By cytogenetic analysis and/or fluorescence in situ hybridization (FISH) on interphase nuclei we found an increased copy number of chromosome 3 in 22/36 (61%) successfully analysed cases, including 8/12 cases with extranodal MZBCL, 8/13 cases with nodal MZBCL, and 6/11 patients with splenic MZBCL. Sensitivity of interphase cytogenetics was somewhat higher than that of conventional cytogenetic investigation. Structural chromosomal changes involving at least one chromosome 3 were seen in 11/20 cases with an increased copy number of chromosome 3: +del(3)(p13) was demonstrated in three cases, and was the sole chromosomal abnormality in one of them; +i(3)(q10) was seen in two other patients; and rearrangements involving various breakpoints on the long arm of chromosome 3 were found in the remaining cases. FISH on metaphase spreads confirmed these structural abnormalities and additionally showed two unexpected translocations involving chromosome 3. We conclude that: (1) trisomy 3 occurs in a high proportion of extranodal, nodal and splenic MZBCL; (2) FISH on interphase nuclei is an additional and sensitive tool in detecting an increased copy number of chromosome 3 in MZBCL; (3) additional structural abnormalities involving the long arm of chromosome 3 are frequent but non-recurrent and are perhaps secondary changes; and (4) abnormalities such as +del(3)(p13) and +i(3)(q10) suggest that genes located on the long arm of chromosome 3 are of particular importance in the pathogenesis of MZBCL.  相似文献   
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Twenty-one patients with dermatitis herpetiformis were typed for HLA-ABC and -DR determinants. The incidence of HLA-AI, -B8 and -DR3 antigens was found to be significantly higher (P: = 10?3, <10?6 and <10?6, respectively) among patients with dermatitis herpetiformis than among the normal population. HLA-DR3 was found in 85.7% of patients, HLA-B8 in 66.7% and HLA-Ai in 61.9% only. These results indicate that HLA-DR3 is the antigen primarily associated in dermatitis herpetiformis and the latter antigens (HLA-Ai and -B8) are present in increased incidence, probably due to the known linkage disequilibrium of these antigens with HLA-DR3.  相似文献   
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We hypothesized that pacing at sites other them the right ventricular (RV) apex or at two or more ventricular sites would activate the myocardium more rapidly and improve cardiac function in patients undergoing coronary revascularization or aortic valve replacement. Epicardial electrodes were placed on the right atrium (A), RV paraseptal area close to the RV apex (B), RV outflow tract (C), LV apex (D), in patients undergoing bypass surgery. At constant rate and AV delay, we measured CO during A pacing, DV1 pacing at B, C, D, and various combinations of sites in random order in ten patients with EF > 50% and 27patients with EF ≤ 50%. When pacing at two sites, we made one electrode a cathode and one an anode and noted two distinct thresholds by careful observation of the 12-lead ECG. There were no significant differences in CO, systemic vascular resistance, systolic, or mean arterial pressure. Significant differences were noted in QRS duration, which increased progressively going from AAI to 3-site, 2-site, and single site pacing (P < 0.05 each comparison). Thus: (1) QRS duration correlated inversely with the number of ventricular sites paced; (2) despite this, CO did not improve irrespective of baseline EF; (3) multisite pacing produced multiple distinct thresholds which appeared to be related to the number of sites paced, and (4) unique ECG patterns confirmed multisite pacing.  相似文献   
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Background: Tissue proliferation is the major cause of in-stent restenosis (ISR). Thus, debulking of material should be the most favorable method to treat ISR. The present study was performed to test the clinical and angiographic outcome of directional coronary atherectomy (DCA) in the treatment of restenosis within different stents. Methods and Results: Fifty patients with ISR in single stents (12 Palrnaz-Schatz stents, 8 Pura stents, 10 Multilink stents, 10 NIR stents, 8 Wallstents, and 2 Microstents) underwent DCA with adjunctive balloon angioplasty in 38 patients. Primary success was achieved in 48 patients (96%). Two patients developed CK-MB elevations, one with a Q-wave infarction. Some minor technical problems occurred with respect to the different stent types. The percent diameter stenosis decreased from 76 ± 7% at baseline to 29 ± 6% after atherectomy (P < 0.0001) and 20 ± 4% after adjunctive PTCA, and it increased to 45 ± 19% at 4-month angiography (P < 0.0001). Angiographic restenosis occurred in 14 (29.2%) of 48 patients who were reevaluated after 4 months. Conclusion: While DCA is able to remove u significant amount of intimal tissue in selected patients with in-stent restenosis, new atherectomy catheter designs are required to make this a feasible and safe procedure.  相似文献   
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小胶质细胞变性对认识衰老相关的神经退变和神经退行性疾病的发病机制非常重要.本研究通过铁蛋白免疫组织化学方法来分析非痴呆和阿茨海默病患者大脑中的小胶质细胞形态特征.作者的主要假设为,铁储存蛋白-铁蛋白的表达提高小胶质细胞对退化的敏感性,尤其是在老年大脑中,因为衰老的小胶质细胞越来越无力维持铁环境稳定,而游离铁可促进氧化损伤.在24例34-97岁的病例中,小胶质细胞对铁蛋白的免疫反应被发现组成一个较大的HLA-DR抗体标记的小胶质细胞池.在老年尤其是AD大脑中,铁蛋白阳性的大部分小胶质细胞呈现出异常的形态学变化,即营养不良.铁蛋白阳性的营养不良小胶质细胞和AD组织中的老年斑之间并未发现空间相关性.对平均死亡时间(10.94±5.69)h的人脑组织的研究显示,小胶质细胞营养不良的出现不依赖于死亡时间,因而不是组织自溶的产物.这些结果均提示,包含铁储存和新陈代谢的小胶质细胞的变性可能是通过其高暴露于氧化应激.作者推论,铁蛋白免疫组织化学法可能是检测人脑小胶质细胞退行性变的有效方法.  相似文献   
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