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101.
102.
Ghanem A Röll W Hashemi T Dewald O Djoufack PC Fink KB Schrickel J Lewalter T Lüderitz B Tiemann K 《Echocardiography (Mount Kisco, N.Y.)》2006,23(10):900-907
Echocardiography is an established method to estimate left-ventricular mass (LVM) in mice. Accuracy is determined by cardiac size and morphology and influenced by mathematical models. We investigated accuracy of three common algorithms in three early developmental stages. High-resolution echocardiography was performed in 35 C57/BL6-mice. Therefore, two-dimensional-guided M-mode echocardiography and parasternal short- and long-axis views in B-mode were obtained. LVM was assessed in vivo applying Penn (P), Area Length (AL), and Truncated Ellipsoid (TE) algorithms and validated with histomorphometry. Regression analysis of all mice showed fair estimation of LVM assessed with M-mode-based Penn algorithm (y = 0.6*x - 0.12, r: 0.71). In contrast two-dimensional assessment of LVM revealed close linear relationship with histomorphometry (y(AL)= 1.21*x - 12.1, r: 0.88, y(TE)= 1.38*x - 2.88, r: 0.86). Bias was lowest for LVM-AL at diastole underestimating 3.2%. In concordance with the summarized data, LVM-P revealed lower regression coefficients and significant underestimation in all three subgroups. Small hearts (<50 mg, n = 12) correlated best with LVM-AL at systole. Hearts of adolescent (50-75 mg, n = 13) and adult (75-100 mg, n = 10) mice revealed close linear relationship with LVM-AL and LVM-TE at diastole. Echocardiographic assessment of LVM is feasible in hearts weighting less than 50 mg and can be estimated best in systole. Hearts weighting more than 50 mg are estimated most accurately by means of LVM-AL at diastole. 相似文献
103.
It has been shown that orexin neuropeptides contribute to morphine-induced physical dependence. The locus coeruleus (LC), which receives a dense extra-hypothalamic orexinergic projection, is a key brain region implicated in the expression of somatic signs of morphine withdrawal syndrome. The aim of the present study is to investigate the role of LC orexin type 1 receptors (OXR1) on naloxone-precipitated morphine withdrawal signs in rats. Adult male Wistar rats were rendered dependent on morphine by subcutaneous (s.c.) injection of morphine sulfate (10 mg/kg) at an interval of 12 h for 9 days. On day 10, naloxone (1 mg/kg i.p.) was injected 2 h after morphine administration. Somatic signs of withdrawal were then evaluated in a clear Plexiglas test chamber (30 cm diameter, 50 cm height) for 25 min. One group of animals received intra-LC SB-334867-A, a selective OXR1 antagonist, (100 μM, 0.2 μl) immediately before naloxone. In the control group, SB-334867-A vehicle was microinjected into the LC in the same manner. The results showed that intra-LC OXR1 receptor blockade significantly decreased the somatic signs of withdrawal including chewing, diarrhea, scratching, teeth chattering, wet-dog shake and ptosis. These results suggest that activation of OXR1 in the LC might be involved in the expression of withdrawal signs in morphine dependent rats. 相似文献
104.
Zahra Mojtahedi Bijan Khademi Seyed Basir Hashemi Seyed Mohammad Bagher Abtahi Mohammad Ali Ghasemi Mohammad Javad Fattahi Abbas Ghaderi 《Pathology oncology research : POR》2011,17(1):7-10
Inflammation has been linked to various steps in tumorigenesis. Interleukin (IL)-6 and IL-18 are two inflammatory cytokines
whose serum concentrations are elevated in several types of cancer, including head and neck squamous cell carcinoma (HNSCC)
in some studies. This study was designed to analyze the serum concentrations of these cytokines in Iranian HNSCC patients.
Serum IL-6 and IL-18 concentrations were assayed by ELISA commercial kits in 65 untreated patients and 20 healthy volunteers.
Serum IL-6 concentration was significantly increased in patients compared to healthy individuals (p < 0.000). IL-6 concentration increased as the tumor stage progressed, and a significant difference appeared between stage
IV vs. stage I/II/III (p = 0.03) disease. Although serum IL-18 concentration was higher in patients than in healthy individuals, the difference was
not statistically significant (p = 0.06). Moreover, there was no association between serum IL-18 concentration and tumor stage (p = 0.47). A significant difference was observed in serum IL-18 concentration according to the gender with higher IL-18 concentration
in male patients (p = 0.01). In conclusion, serum concentration of IL-6 might correlate with the stage of tumor progression in Iranian HNSCC
patients. Further studies with larger numbers of patients are required to exclude the possible minor correlation of serum
IL-18 concentration with tumor stage. 相似文献
105.
Hany Bedair Nicholas Ting Christina Jacovides Arjun Saxena Mario Moric Javad Parvizi Craig J. Della Valle 《Clinical orthopaedics and related research》2011,469(1):34-40
Background
Synovial fluid white blood cell count is useful for diagnosing periprosthetic infections but the utility of this test in the early postoperative period remains unknown as hemarthrosis and postoperative inflammation may render standard cutoff values inaccurate. 相似文献106.
Mehdi Hosseini Tehrani Asoo Ali Mahmoudi Hassan Hashemi Syed Jafar Oskouee Javad Amuzadeh Mohammad Taher Rajabi Masoomeh Taherzadeh Hamideh Shenazandi 《国际眼科杂志》2008,8(6):1095-1100
目的:评价利用活体异体结膜缘和羊膜移植治疗化学性眼外伤造成的角膜缘干细胞缺失的临床效果。方法:从2005-07/2007-12,本研究包括了9名男性化学性眼外伤患者(10眼)。所有患者接受了亲属活体异体结膜缘和羊膜移植,2例眼接受了睑缝术。用环孢菌素和泼尼松龙进行全身性免疫抑制。结果:在3例眼中观察到完全角膜上皮化(30%),其中1例在术后1.5mo出现免疫排斥,角膜溶解引起穿孔,加大全身性免疫抑制剂量来控制病情。3例眼中植片无法在角膜表面重新形成上皮,被定为原发性失败。其余4眼有部分上皮形成,但上皮细胞无法完全覆盖角膜表面。术前最佳矫正视力从手动到1m处数指,术后最佳矫正视力从光感到20/80。有5眼视力得到改进,不需其他治疗。手术失败的主要原因为干眼症和持续性炎症。结论:对于能控制泪量和眼部炎症的病例,亲属活体异体角膜缘和羊膜移植是治疗化学性眼外伤造成的角膜缘干细胞缺失最佳方法之一。 相似文献
107.
Jack N. Sees Jr. Javad Towfighi David B. Robins Roger L. Ladda 《Fetal and pediatric pathology》1990,10(5):807-818
Neuropathologic examination of two siblings with phenotypic features consistent with Marden-Walker syndrome revealed central nervous system abnormalities which include reduction in the number of spinal anterior horn cells. The occurrence of these changes in a sibling pair provides strong evidence for a genetic etiology. The relationship between the neuropathologic changes and other phenotypic manifestations in this syndrome and in the closely related syndrome of Pena-Shokeir are discussed. 相似文献
108.
Mehrabi A Golling M Busch Ch Hashemi B Ahmadi R Völkl A Gebhard MM Klar E Kraus T 《The Journal of surgical research》2002,105(2):128-135
Mechanical liver manipulation can lead to hepatic microcirculation (MC) impairment. The pathobiochemical relevance of this phenomenon is not fully understood. Microdialysis (MD) allows a quantification of metabolic products in interstitial fluid, thus enabling analysis of the hepatic metabolic state during changes of liver perfusion. The aim of the study was to quantify the functional effects of standardized surgical liver preparation both on liver metabolism and microperfusion. Two groups of animals (pigs, n = 25) were formed: In the trial group (TG; n = 13) the liver was mobilized, followed by hilar preparation. In the control group (CG; n = 12) mobilization of the liver without hilar dissection was performed. Surgical manipulation was followed by an observation in both groups. Hepatic interstitial glucose, lactate, and glutamate concentrations were detected by MD and liver MC by thermodiffusion. During liver mobilization MC decreased significantly in both groups (TG; 86.7 +/- 2.0 to 73.4 +/- 2.3 ml/100 g min; and CG; 88.3 +/- 3.1 to 71.9 +/- 2.2 ml/100 g/min). In the trial group levels decreased further during hilar preparation reaching minimal values of 65.6 +/- 2.8. After preparation MC recovered to baseline. Glucose, lactate, and glutamate concentrations increased significantly during liver mobilization in the trial (glucose; 0.52 +/- 0.13 to 0.88 +/- 0.19 mmol/L; lactate; 0.34 +/- 0.07 to 0.54 +/- 0.07 mmol/L; glutamate; 34.5 +/- 3.6 to 52.6 +/- 8.0 micromol/L) and control group (glucose; 0.58 +/- 0.06 to 0.95 +/- 0.13 mmol/L; lactate; 0.30 +/- 0.06 to 0.49 +/- 0.07 mmol/L; glutamate; 32.9 +/- 2.36 to 56.1 +/- 5.12 micromol/L). Throughout hilus preparation maximum values could be measured in TG (glucose; 1.69 +/- 0.34; lactate; 0.90 +/- 0.18; glutamate; 63.5 +/- 7.2). After termination of mobilization or preparation baseline concentrations were reached again. MD allows monitoring of metabolic changes in hepatic parenchyma. Surgical liver preparation leads to changes of intrahepatic glucose, lactate, and glutamate levels (without alterations of parameters in systemic plasma) along with hepatic MC impairment. Reconstitution of hepatic MC was accompanied by rapid normalization of metabolic parameters. By measuring specific parameters, MD could prove to be of use for functional assessment of metabolic effects due to MC disturbances. 相似文献
109.
Parvizi J Schall DM Lewallen DG Sim FH 《Clinical orthopaedics and related research》2002,(403):127-134
The outcome of uncemented hip arthroplasty in patients with Paget's disease is unknown. The clinical and radiographic records of patients with Paget's disease affecting the hip who had total hip arthroplasty using uncemented components against pagetic bone were reviewed. There were 18 patients (19 hips) with an average age of 71.3 years (range, 54-85 years). Followup averaged 7 years (range, 2-15 years). Surgery often was reported to be demanding technically because of hard sclerotic bone and excessive bleeding in some patients. Estimated blood loss averaged 996 mL (range, 200-2500 mL). Harris hip scores improved significantly. There was clinical and radiographic evidence of bone ingrowth in all patients. Six of 19 hips had heterotopic bone. One hip had severe Brooker Grade IV heterotopic ossification and the patient required excision of the ossification at 5 years. One hip was unstable (subluxating) at the latest followup. There was no revision for component loosening and no recognized cases of clinical or radiographic loosening of any uncemented implants. Results of total hip arthroplasty using uncemented components in patients with Paget's disease are excellent overall, with an extremely low risk of component loosening during the first decade after implantation. These patients may be at higher risk for heterotopic bone formation and increased perioperative blood loss because of hypervascularity of the bone. 相似文献
110.
Parvizi J Seel MJ Hanssen AD Berry DJ Morrey BF 《Clinical orthopaedics and related research》2002,(397):356-361
When severe bone loss precludes reimplantation of a new patellar component during revision knee arthroplasty, the treatment options include patellar bone grafting, patellar component resection arthroplasty, and patellectomy. The purpose of this study was to evaluate the clinical and functional results of patellar component resection arthroplasty for the severely compromised patella for which insertion of another patellar component was not possible. Thirty-five knees (31 patients) were treated with patellar component resection arthroplasty for aseptic patellar component failure associated with severely compromised patellar bone stock. Followup averaged 7.9 years (range, 2-18 years). There was a significant improvement in Knee Society pain and function scores. Pain relief was more dramatic than functional improvement. The range of motion also improved significantly and in particular preoperative extensor lag was resolved in the majority of patients. Patients treated with isolated patellar resection arthroplasty were more likely to have continuing pain and require reoperation compared with patients who had concomitant revision of the tibial and femoral components. Correct positioning and the stability of tibial and femoral components should be tested carefully at the time of patellar resection arthroplasty and considered for revision if malpositioned either axially or rotationally. 相似文献