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PURPOSE: Bone healing is impaired in diabetes mellitus, particularly due to increased collagen breakdown. Recently, tetracyclines have been used to treat experimental bone defects because they have anticollagenolytic properties, and positive effects on the healing process have been obtained. The objective of this study was to develop a computer-assisted histomorphometric technique to quantitatively determine the amount of regenerating bone within experimental bone defects in a diabetic rodent model. MATERIALS AND METHODS: This study examined the effects of systemic doxycycline administration on the healing of tibial bone defects in healthy albino rats and in experimentally induced diabetic rats. Twenty-four female albino rats were assigned to 4 groups: diabetic, diabetic plus doxycycline, control, or control plus doxycycline. The standardized bone defects were histomorphometrically examined 10 and 30 days postoperatively. Histomorphometric analysis of the amount of new bone formation was performed using the Zeiss Vision image analysis program KS 400 (Kontron Elektron GmbH, Eching, Germany). RESULTS: At 10 days of healing, the diabetic groups exhibited inferior healing compared with the control groups in terms of the amount of new bone formation within the defects. However, the effect of doxycycline administration to the diabetic and control groups was not statistically different. At 30 days of healing, there were no statistically significant differences between the amount of newly formed bone in any of the groups. CONCLUSIONS: This study found that doxycycline administration did not significantly alter the amount of new bone formation during the healing of bone defects in control and diabetic rats.  相似文献   
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BACKGROUND: This is a first attempt to evaluate the reliability and factor structure replicability of the Temperament Evaluation of Memphis, Pisa, Paris and San Diego Autoquestionnaire (TEMPS-A) in its Turkish Version. The questionnaire is a self-report 110-item measure that postulates five affective temperaments-the depressive, cyclothymic, irritable, hyperthymic, and anxious-which embody both strengths and liabilities along affective lines. METHODS: The questionnaire was administered to 658 clinically-well subjects in a Turkish university circle. We undertook item analysis and test-retest reliability. We then examined internal consistency through factor analysis with PCA rotation. RESULTS: We found good to excellent test-retest reliability (0.73-0.91), and internal consistency (0.77-0.85). We deleted 10 items with factor loading <0.20 for their own subscales, resulting in a questionnaire with 99 items. Despite considerable overlap between depressive and cognitive anxiety traits, a distinct "nervous"-anxious factor emerged as well, and the hypothesized (original English) 5-factor structure of the TEMPS-A was supported. Cut-offs for each temperament were based on z-scores higher than +2S.D. Dominant irritable (3.7%), nervous-anxious (3.7%) and depressive (3.1%) temperaments were the most common in this population, whereas dominant cyclothymic (1.7%) and hyperthymic (1.2%) temperaments were relatively uncommon. These temperaments tended to lose their intensity with age. As expected, women scored significantly higher on the nervous-anxious, and men on the hyperthymic temperaments. LIMITATIONS: The sample was composed of younger subjects with higher education than the general population of Turkey. Although the distribution of the scores for each of the temperaments deviated somewhat from normal curves, for heuristic reasons we did attempt to provide prevalence rates based on z-scores. CONCLUSION: In this preliminary version of the TEMPS-A, we have retained 100 (of the original 110) traits loading >0.20. Some deleted items referred to sleep, others appeared socially desirability traits in the Turkish culture endorsed by many subjects. Nonetheless, item analyses within each factor revealed traits indicative of personal assets (specific to each temperament) along with those which might represent vulnerability to affective illness. This is in line with the hypothesized original theoretical framework of the senior authors. Even in this "first pass," in its Turkish version the TEMPS-A is a reliable and valid instrument. Further refinement of the instrument will require the study of a nationally representative sample in Turkey.  相似文献   
4.
Hypoxia treatment of normal peritoneal fibroblasts results in alterations that are characteristic for fibroblasts obtained from postoperative peritoneal adhesion tissue. In this study, we have shown that hypoxia treatment enhances normal peritoneal fibroblast elimination by lymphokine-activated killer cells to the level of adhesion tissue fibroblasts, suggesting a pivotal role of hypoxia in the adhesion development.  相似文献   
5.
Pneumococcal sepsis is a life-threatening complication in splenectomised patients even since the introduction of a polyvalent pneumococcal vaccine. Eight episodes of pneumococcal sepsis in seven properly vaccinated splenectomised patients are described. All but two of the causative serotypes were included in the vaccine. The fact that most of the patients were immunosuppressed may explain the failure of the vaccine in these particular patients. A survey of 59 episodes of pneumococcal bacteraemia during 1982 at the Soroka Medical Center, however, shows that 32% of the strains of pneumococci isolated were among seven types not included in the vaccine. The addition of continuous antibiotic prophylaxis in vaccinated and splenectomised patients is suggested.  相似文献   
6.
The purpose of this study was to identify a reliable reference point for measuring anterior intermeniscal ligament thickness and to investigate the morphological characteristics of the ligament at its attachment site to anterior horns of both menisci by MRI. MRI was performed in 98 knees of randomly chosen patients. The anterior intermeniscal ligament was detected in 61 knees (62.2%). The average ligament length was 29.8 mm. Men had significantly longer anterior intermeniscal ligament than women patients (32.5 vs. 27.8 mm). The thickness of anterior intermeniscal ligaments at their attachment sites to menisci was usually less than 3 mm; a thickness of 3 mm or more at the attachment site to anterior horns of the meniscus was defined as "cordlike." It is suggested that the "cordlike" pattern is a variation of the anterior intermeniscal ligament's attachment characteristics, and that this might have a significant role in meniscal translations during knee motion, and also that the "cordlike" pattern could be clinically important with respect to its relationship to the anterior horn of medial meniscus. The attachment site of the ligament is a reliable reference point for measuring its thickness.  相似文献   
7.
The aim of this study was to compare ambulatory blood pressure monitoring (ABPM) parameters in offspring with at least one hypertensive parent (HP) to offspring with normotensive parents (NP) and to determine whether gender of parent or child might influence the association between parental hypertension and blood pressure (BP). Eighty-nine healthy children (mean age 11.1 ± 3.9 years) with HP and 90 controls (mean age 10.5 ± 3.1 years) with NP were recruited. Age, gender, and height did not differ between the two groups, whereas children of HP had higher weight, body mass index (BMI), and waist circumference compared with healthy controls. No difference was found in casual BP between the two groups. In contrast, during ABPM daytime and nighttime mean systolic and diastolic BP and mean arterial pressure (MAP) standard deviation scores (SDS) were significantly elevated in children with HP. The mean percentage of nocturnal BP decline (dipping) was not significantly different between the two groups. Children with hypertensive mothers had higher daytime systolic and MAP SDS than controls; no such difference was detected for children with hypertensive fathers. Daytime systolic and MAP SDS were significantly elevated in boys with HP compared with boys with NP but failed to be significant in girls. Multiple linear regression analysis showed that parental history of hypertension (B = 0.29) and BMI (B = 0.03) were independently correlated with increase of daytime MAP SDS. Early changes in ambulatory BP parameters were present in healthy children of HP. BP in HP offspring was influenced by the gender of the affected parent and the offspring.  相似文献   
8.
OBJECTIVES: Esophageal strictures and esophagorespiratory fistulas are complications of malignant esophageal tumors, which are difficult to manage. The efficacy of self-expanding metal stents (SEMS) for palliation of malignant esophageal strictures and fistulas was investigated prospectively. METHODS: Forty-three SEMS were inserted in 41 patients with malignant esophageal stricture or fistula. Our series included 32 men and nine women, of whom median age was 61.4 years. Twenty nine stents were inserted for stricture, ten for esophago-tracheal fistula, and four esophago-pleural fistula. Stents were inserted endoscopically under fluoroscopic control. RESULTS: SEMS implantation was technically successful in 40 of 41 patients. A second stenting was needed in two patients. Median dysphagia score improved from 3.4 to 1.3. The covered SEMS was succesful in completely sealing 85.7% of the fistulas. Complication occurred in 11 (26.8%) patients. Especially in the case of tumor stenoses in the distal esophagus, complication rate was higher (44%). In total six patients (14.6%) died after stent placement during early postoperative period. Procedure-related mortality was 4.8% (2/41). CONCLUSIONS: We conclude that treatment of malignant esophageal obstructions, including esophagorespiratory fistulas, with SEMS is an alternative palliative procedure. Furthermore SEMS implantation seems more safe in the case of tumor stenoses locating in the middle esophagus.  相似文献   
9.
We aimed to evaluate whether the subtle metabolic cerebral changes are present in normal-appearing white matter on conventional MRI, in patients with acute brucellosis, by using MR spectroscopy (MRS). Sixteen patients with acute brucellosis and 13 healthy control subjects were investigated with conventional MRI and single-voxel MRS. Voxels were placed in normal-appearing parietal white matter (NAPWM). N-Acetyl aspartate (NAA)/creatine (Cr) and choline (Cho)/Cr ratios were calculated. There was no significant difference between the study subjects and the control group in NAA/Cr ratios obtained from NAPWM. However, the Cho/Cr ratios were significantly higher in patients with acute brucellosis compared to controls (p=0.01). MRS revealed metabolic changes in normal-appearing white matter of patients with brucellosis. Brucellosis may cause subtle cerebral alterations, which may only be discernible with MRS. Increased Cho/Cr ratio possibly represents an initial phase of inflammation and/or demyelination process of brucellosis.  相似文献   
10.
Introduction: Pyelonephritis-induced renal scarring in children is a major predisposing factor for proteinuria, hypertension, and ultimate renal failure. The aim of this study was to investigate and compare the efficacy of Tc99m dimercaptosuccinic acid (Tc-DMSA) renal scintigraphy and renal ultrasonography (USG) in detecting renal scars in children with primary vesicoureteral reflux (VUR). Materials and methods: Tc-DMSA scan and USG studies were done in 62 children who were admitted to our clinic between 1997 and 2003 because of documented urinary tract infection (UTI) and diagnosed with primary VUR. Renal scarring detection rates of Tc-DMSA scan and USG were compared according to reflux grades. Results: In the whole group, renal scars were detected by Tc-DMSA scan and USG in 55% and 38% of refluxing units, respectively. Detection rates of Tc-DMSA and USG according to reflux grades were as follows: 47% and 29 % in low-grade VUR (grades 1 and 2), 46 % and 25% in mid-grade VUR (grade 3), 76% and 65% in high-grade VUR (grades 4 and 5), respectively. Conclusion: USG was found to be an inappropriate study in the detection of renal parenchymal scars, irrespective of the reflux grade. In this study, Tc-DMSA scan detected scars in 35% of kidneys reported to be normal on USG.  相似文献   
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