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91.
目的:通过光学相干断层成像(OCT)检测高度近视合并青光眼患者视神经纤维层厚度的变化规律。方法:选取2017-01/12于我院进行治疗的高度近视合并青光眼患者80例160眼作为观察组,并选择同期于我院进行体检的健康志愿者60例120眼作为对照组。采用OCT分析所有受检者视神经纤维层厚度。结果:与对照组受检者相比,观察组患者鼻侧、颞上、鼻下、鼻上、颞下及全周平均视神经纤维层厚度均降低,而颞侧视神经纤维层厚度升高(P<0.05),且观察组中屈光度-10.00^-11.00D的患者鼻侧、颞上、鼻下、鼻上、颞下及全周平均视神经纤维层厚度均显著高于屈光度≥-12.00D的患者(P<0.05)。Spearman相关分析结果显示,观察组患者屈光度的绝对值与鼻侧、颞上、鼻下、颞下及全周平均厚度视神经纤维层厚度呈负相关,与颞侧视神经纤维层厚度呈正相关。结论:高度近视合并青光眼患者除颞侧外各象限视神经纤维层变薄。  相似文献   
92.
Immunologic heterogeneity of diffuse large cell lymphoma   总被引:2,自引:0,他引:2  
The cellular lineage of 57 diffuse large-cell lymphomas (DLCLs) was determined using a panel of monoclonal antibodies directed against lineage-restricted and -associated T, B, and monocyte antigens. The majority (82%) were of B cell lineage as determined by the expression of sig and/or B1, with the remaining 16% being of T cell lineage and 2%, of monocyte-myeloid lineage. By the expression of other B cell- restricted and -associated antigens, two major and two minor subgroups could be identified. These subgroups expressed the following phenotypes: (1) B1+B4+sIG+B2- (51%); (2) B1+B4+sIg+B2+ (29%); (3) B1+B4+sIg-B2+ (10%); and (4) B1+B4-sIg+B2- (10)%. The morphology of transformed lymphocytes, the weak to absent expression of the early B cell antigens B2 and sIgD, and the absence of the late B cell differentiation antigens PCA-1 and PC-1 suggested that these tumors were the neoplastic counterparts of normal B cells at the mid-stages of differentiation. Further support for the notion that B-DLCLs correspond to transformed B lymphocytes was concluded from the observation that B cells could be identified in normal spleen that expressed the cell surface phenotype and morphological appearance of the majority of B- DLCLs.  相似文献   
93.
Abnormal clonogenic potential of T cells from multiple myeloma patients   总被引:2,自引:0,他引:2  
Peripheral blood lymphocytes (PBLs) from multiple myeloma patients are defective in both proportion and absolute numbers of OKT4+ cells and have a normal proportion but reduced absolute number of OKT8+ cells. To assess the functional capabilities of the T cells in myeloma patients, we cloned the T cells in PBLs using limiting dilution conditions in which 100% of OKT4+ and OKT8+ T cells in normal PBLs are able to form a clone. In contrast, the OKT8+ cells from PBLs of five of seven multiple myeloma patients were severely compromised in their clonogenic potential; only 7% to 25% of OKT8+ T cells appeared to give rise to a clone. Clonogenic potential of the OKT4+ cells in patients was more nearly normal. Analysis of two multiple myeloma patients with abnormally low numbers of T cells in PBLs revealed the existence of abnormalities in the progenitors of T cell clones. In both patients, two to three times as many T cell clones were observed as would have been expected based on the number of PBLs cultured at limiting dilution, indicating that OKT4-8- cells in PBLs are capable of giving rise to OKT4+ and, at lower frequency, to OKT8+ clonal progeny in vitro. We conclude that purely quantitative assessment of T cell subsets should be interpreted with caution, since proportionately normal numbers of OKT8+ cells in patient PBLs are seriously compromised in their ability to give rise to clonal progeny in vitro, and since there appears to be a OKT4-8- population of T cells in PBLs that are committed to become OKT4+ or OKT8+ T cells, but are unable to do so in vivo.  相似文献   
94.
95.
BACKGROUND: The rate of acceptance onto dialysis programmes has doubled in the past 10 years and is steadily increasing. Early detection and treatment of renal failure slows the rate of progression. Is it feasible to screen for patients who are at increased risk of developing renal failure? We have audited primary care records of patients aged 50-75 years who have either hypertension or diabetes, and are therefore considered to be at high risk of developing renal insufficiency. Our aim was to see whether patients had had their blood pressure measured and urine tested for protein within 12 months, and plasma creatinine measured within 24 months. METHODS: This was a retrospective study of case notes and computer records in 12 general practices from inner and greater London. A total of 16,855 patients were aged 50-75 years. From this age group, 2693 (15.5%) patients were identified as being either hypertensive or diabetic, or both. RESULTS: Of the 2561 records audited, 1359 (53.1%) contained a plasma creatinine measured within 24 months, and 11% of these (150) had a value > 125 micromol/l. This equates to a prevalence of renal insufficiency of > 110,000 patients per million in this group. Forty two patients (28%) had been referred to a nephrologist. Of records audited, 73% contained a blood pressure measurement and 29% contained a test for proteinuria within 12 months. CONCLUSIONS: There is a high prevalence of chronic renal insufficiency in hypertensive and diabetic patients. It is feasible to detect renal insufficiency at a primary care level, but an effective system will require computerized databases that code for age, ethnicity, measurement of blood pressure and renal function, as well as diagnoses.  相似文献   
96.
晚期前列腺癌的诊断与治疗(附41例报告)   总被引:9,自引:0,他引:9  
目的:提高晚期前列腺癌的治疗效果。方法:回顾性分析采用睾丸切除术、内分泌治疗、放射治疗和同位素治疗等综合治疗的41例晚期前列腺癌患者资料。结果:41例经随访3~12个月,尿路梗阻症状均有不同程度改善,前列腺明显缩小,血清前列腺特异性抗原迅速降低,骨痛缓解。结论:积极的综合治疗能明显提高患者的生活质量  相似文献   
97.
目的:获得重组FAS抗原,用于抗体制备及进一步的功能分析。方法:用PCR技术从完整的FAScDNA克隆上扩增其编码胞外区的部分,将PCR产物直接克隆到pGEM-T载体系统,DNA序列分析证实序列完全正确;用EcoRⅠ和SalⅠ将FAS胞外区片段切出,定向克隆到经同样酶切处理的pGEX-KG表达载体,转化大肠杆菌,经优化IPTG的诱导条件,获得了FAS胞外区与谷胱甘肽-S-转移酶的融合蛋白高效表达;用亲合层析法从细菌粗提物中纯化了GST-FAS融合蛋白,免疫家兔制备了抗FAS抗体。结果:用重组FAS为免疫原制备的抗体能诱导U937细胞产生细胞凋亡。结论:重组FAS抗原和制备的抗体能用于对FAS系统的功能研究  相似文献   
98.

Objectives

The aim of this study was to determine the prevalence of apical periodontitis (AP) detected in cone beam CT (CBCT) images from a database.

Methods

CBCT images of 300 Brazilian patients were assessed. AP images were measured in three dimensions. Age, gender, number and location of total teeth in each patient were considered. AP location was considered according to tooth groups. The extent of AP was determined by the largest diameter in any of the three dimensions. Percentages and the χ2 test were used for statistical analysis.

Results

AP was found in 51.4% of the patients and in 3.4% of the teeth. Higher prevalence of AP was found in 60- to 69-year-olds (73.1%) and in mandibular molars (5.9%) (p < 0.05). Inadequate endodontic treatment presented higher prevalence of AP (78.1%).

Conclusions

AP can be frequently found in CBCT examinations. The presence of AP has a significant association with patients'' age, and tooth type and condition. CBCT databases are useful for cross-sectional studies about AP prevalence in a population.  相似文献   
99.
100.
Does altered biomechanics cause marrow edema?   总被引:21,自引:0,他引:21  
Schweitzer  ME; White  LM 《Radiology》1996,198(3):851
  相似文献   
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