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81.
BACKGROUND: Elevated C-reactive protein (CRP) has been found to correlate with higher risk for cardiac events in patients with acute myocardial infarction (AMI). It has been suggested that CRP may be involved in initiation process of coagulation; however, the role of CRP level in the formation of left ventricular (LV) thrombus has not been studied. HYPOTHESIS: This study investigated whether CRP is a risk factor for LV thrombus in patients with AMI. METHODS: Clinical, echocardiographic, and biochemical data were analyzed in 141 consecutive patients (aged 57 +/- 13 years; 33 women) with first anterior AMI. Two-dimensional and Doppler echocardiographic examinations were performed on Days 1, 3, 7, 15, and 30. Blood samples were obtained every day during hospitalization. Serum CRP concentrations were measured by an ultrasensitive immunonephelometry method. RESULTS: Left ventricular thrombus was detected in 33 (23.4%) patients. Univariate analysis showed that patients with LV thrombus had a higher peak creatine kinase (CK) level (2,879 +/- 742 vs. 1,693 +/- 1,210 I/U, p = 0.001), higher peak CRP level (14.9 +/- 7.1 vs. 9.2 +/- 6.8 mg/dl, p = 0.001), higher wall motion score index (1.8 +/- 0.2 vs. 1.5 +/- 0.3, p = 0.002), higher apical wall motion score index (2.35 +/- 0.72 vs. 2.07 +/- 0.70, p = 0.001), larger end-diastolic volume (145.2 +/- 43.7 vs. 116.5 +/- 44.2 ml, p = 0.002), larger end-systolic volume (85.4 +/- 37.2 vs. 62.9 +/- 31.6 ml, p = 0.003), and lower ejection fraction (42.1 +/- 12 vs. 47.3 +/- 13, p = 0.04). In multivariate analyses, only peak CK level (p = 0.0001), LV apical wall motion score index (p = 0.001), and CRP levels (p = 0.001) were independent predictors of LV thrombus formation. CONCLUSIONS: These results suggest that CRP is a risk factor for LV thrombus in patients with AMI.  相似文献   
82.
Molecular mechanisms contributing to the tumorigenesis of pancreatic endocrine tumors (PETs) are still not well understood. Allelic deletions at chromosome 22q12.3 were detected in about 30-60% of PETs, suggesting that inactivation of one or more tumor suppressor genes on this chromosomal arm is important for their pathogenesis. Because the putative tumor suppressor gene tissue inhibitor of metalloproteinase-3 (TIMP-3) has been located at 22q12.3, we undertook a genetic analysis of TIMP-3 to determine its role in the tumorigenesis of PETs. Single-strand conformational polymorphism analysis, methylation-specific PCR, RNA expression analysis, and immunohistochemistry of TIMP-3 were performed in 21 sporadic PETs. Thirteen of 21 PETs (62%) revealed TIMP-3 alterations, including promoter hypermethylation and homozygous deletion. The predominant TIMP-3 alteration was promoter hypermethylation, identified in 8 of 18 (44%) PETs. It was tumor-specific and corresponded to loss or strong reduction of TIMP-3 protein expression. Notably, 11 of 14 (79%) PETs with metastases had TIMP-3 alterations, compared with only 1 of 7 (14%) PETs without metastases (P < 0.02). These data suggest a possibly important role of TIMP-3 in the tumorigenesis of human PETs, especially in the development of metastases, which has to be further evaluated in large-scale studies.  相似文献   
83.
茶多酚治疗慢性酒精性肝损伤的实验研究   总被引:8,自引:0,他引:8  
目的 建立酒精性肝病大鼠模型,观察茶多酚对酒精性肝病大鼠血清氨基转移酶活性和肝脏病理变化的影响,探讨茶多酚对酒精性肝损伤的防治作用。 方法 SD大鼠分成3组:酒精组(酒精7g·kg-1·d-1灌胃)、茶多酚组(酒精7g·kg-1·d-1 茶多酚0.25g·kg-1·d-1灌胃)和对照组(等渗盐水灌胃)。各组分别于4周末、12周末和24周末处死大鼠留取肝脏标本,用于HE染色和Masson染色。 结果 酒精组大鼠血清氧基转移酶水平较对照组升高,茶多酚组大鼠与酒精组相比,其值有明显降低,差异有统计学意义(P<0.05)。HE染色显示酒精组大鼠肝细胞浆出现不同程度的脂肪变性,小叶各带可见不同程度的点、灶状或片状坏死,24周大鼠可见桥接坏死。Masson三色染色可见24周大鼠汇管区边缘有绿染胶原纤维包绕增生,肝窦中可见绿染胶原纤维分布。茶多酚组肝脂肪变和炎症程度轻于酒精组,未发现桥接坏死。 结论 茶多酚对酒精性肝损伤具有一定的保护作用。  相似文献   
84.

Objectives

Sumac (Rhus coriaria L.) is widely used spice which has several properties such as antioxidant, anti-inflammatory and antimicrobial. The purpose of this animal study was to evaluate the effects of sumac extract on levels of receptor activator of nuclear factor-kappa B ligand (RANKL), osteoprotegerin (OPG) expression, serum oxidative status, and alveolar bone loss in experimental periodontitis.

Material and Methods

Twenty-four Wistar rats were separated into three groups: non-ligated (NL, n=8), ligature only (LO, n=8), and ligature and treated with sumac extract (S, n=8) (20 mg/kg per day for 11 days). A 4/0 silk suture was placed around the mandibular right first molars subgingivally; after 11 days, the rats were sacrificed, and alveolar bone loss was histometrically measured. The detection of RANKL and OPG were immunohistochemically performed. Levels of serum total antioxidant status (TAS)/total oxidant status (TOS), and oxidative stress index (OSI) were also analyzed.

Results

Alveolar bone loss was significantly greater in the LO group compared to the S and NL groups (p<0.05). The number of inflammatory cell infiltrate (ICI) and osteoclasts in the LO group was significantly higher than that of the NL and S groups (p<0.05). The number of osteoblasts in the LO and S groups was significantly higher than that of the NL group (p<0.05). There were significantly more RANKL-positive cells in the LO group than in the S and NL groups (p<0.05). OPG-positive cells were higher in S group than in LO and NL groups (p<0.05). TOS and OSI levels were significantly reduced in S group compared to LO group (P<0.05) and TAS levels were similar in S and NL group (p>0.05).

Conclusions

The present study showed that systemic administration of sumac extract may reduce alveolar bone loss by affecting RANKL/OPG balance, TOS and OSI levels in periodontal disease in rats.  相似文献   
85.
ObjectiveThe aim was to compare coronary high-definition CT (HDCT) with standard-definition CT (SDCT) angiography as to radiation dose, image quality and accuracy.ResultsThe intraclass correlation coefficient (ICC) of measured vessel attenuation values in SDCT between the two radiologists was exceedingly good. The ICC was higher in HDCT. The radiation dose of HDCT was higher than that of SDCT. The mean tube current was 180 (mA) in HDCT and 147(mA) in SDCT with the same tube voltage (kVp). There was no significant difference between image quality.ConclusionHDCT has a higher radiation dose but has much more atenuation and the spatial resolution which improve measurement accuracy for imaging coronary arteries.  相似文献   
86.
[Purpose] To assess the effects of different numbers of platelet-rich plasma (PRP) applications on pain and physical function in grade 3 knee osteoarthritis (OA). [Subjects and Methods] A total of 102 patients with grade 3 knee OA were randomly divided into three groups: Group 1 received a single injection of PRP, Group 2 received two injections of PRP two weeks apart, Group 3 received three injections of PRP at 2-weeks intervals. All patients were evaluated with a visual analog scale (VAS), the Western Ontario and McMaster Universities Arthritis Index (WOMAC), and the Timed-Up and Go test (TUG) before the treatment and at 1, 3 and 6 months after the treatment. [Results] Ninety-eight patients (15 males, 83 females) completed the study. The mean ages of the patients were 53.5±6.6, 54.9±5.3, and 55.1±5.6 years in Group 1, Group 2, and Group 3, respectively. Statistically significant improvements were noted in all of the evaluated measures in all of the groups. The mean differences of Group 1-Group 2 and Group 1-Group 3 WOMAC total, WOMAC pain, WOMAC stiffness, and WOMAC function scores were statistically significant. [Conclusion] PRP is an effective treatment for functional status and pain in moderate knee osteoarthritis and a minimum of two injections is appropriate.Key words: Platelet-rich plasma effectiveness, Moderate, Knee osteoarthritis  相似文献   
87.
甲状腺术后瘢痕组织是甲状腺局部分切除术后由于手术方式及缝线填充而形成的组织,甲状腺术后瘢痕组织形成及其发生发展过程同一般的组织损伤修复病理过程一样,为渐进老化阶段的结缔组织,其内小血管稀少,胶原纤维增多[1]。由于甲状腺术后瘢痕组织其质地较硬,活动性差,超声声像图上表现缺乏典型特征,与癌灶极其相似,因此鉴别较困难。本文将介绍超声对于甲状腺术后的随诊应用,分析甲状腺术后瘢痕组织的超声检查特点并着重介绍超声动态观察甲状腺术后瘢痕组织的应用及其发展前景。  相似文献   
88.
89.
The cranio-orbital foramen (COF) is located on the lateral wall of the orbit. It is a potential source of hemorrhage during deep lateral orbital dissection, since it functions as an anastomosis between the lacrimal artery and the middle meningeal artery. The aim of this study was to guide and facilitate the surgical procedures in the orbit, so as to determine a navigational area and the precise location of the COF and to standardize certain anatomical marks. The navigational area of the COF and topographical features were studied in 75 craniums with presented COF. 33 bilateral main COFs, 41 (18 on the right, 23 on the left) unilateral main COFs at the main cranium and 19 accessory COFs were studied for their navigational features on the orbit. The distances between the COF and the fronto-zygomatic suture, supraorbital notch, lateral angle of the superior orbital fissure (SOF) and Whitnall’s tubercle were measured. The mean distance of the COF from the fronto-zygomatic suture, supraorbital notch, lateral angle of the SOF and Whitnall’s tubercle was 26.3, 37.3, 92 and 27.1 mm, respectively. For the navigational area signs of the COF, areas of the orbit that form the transversal and vertical lines are generated on the reference points. Whilst the upper outer area of the orbit contains a potential bleeding risk, the bottom section of the outer column is identified as safe for the surgical operations of the lateral orbital wall. The fronto-zygomatic suture and Whitnall’s tubercle are recommended as the most reliable navigational landmarks for identifying the COF. Hence, the transversal and vertical orientation of the COF should be mastered by the surgeons reconstructing the anterior base of the skull and the orbit.  相似文献   
90.
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