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81.
82.
Prediabetes [impaired glucose tolerance (IGT) and/or impaired fasting glucose (IFG)] is a major risk factor for T2DM as well as for cardiovascular disease and mortality. In the present study, the platelet aggregation and fibrinogen levels were investigated in prediabetic subjects who had no confounding factors such as hypertension, obesity or dyslipidemia. Thirty-nine subjects with prediabetes (24 IFG and 15 IGT) and age, sex and BMI matched 36 healthy controls were enrolled. Platelet aggregation, fibrinogen and hsCRP levels, HOMA-IR and HOMA-beta indexes were determined. Platelet aggregation induced by collagen, epinephrine or ADP was not different (p=0.93, p=0.90 and p=0.29, respectively) between two groups, whereas fibrinogen levels were significantly higher (p=0.006) in the prediabetics when compared to controls. hsCRP levels, HOMA-IR and HOMA-beta indexes in the two groups were not different. The power of the study was calculated according to the results and established as 0.97 for collagen, 0.95 for epinephrine and 0.83 for ADP. Despite the high plasma fibrinogen levels, the platelet aggregation in prediabetics was not different when compared to healthy controls. These data suggest that platelet aggregation may not be involved in the mechanism of prothrombotic state in prediabetic state.  相似文献   
83.
Investigators can infer how much reduction in volume has occurred since brain volume was at its peak, by combining measures of brain volume with measures of intracranial volume (ICV). Several methodologies have been proposed to asses the ICV. However, we have not seen a gold-standard study evaluating the results of the methodologies for the assessment of ICV. In the present study, the actual intracranial volume of 20 dry skulls was measured using the water-filling method, using this as a gold standard. Anthropometry, cephalometry, point-counting, and planimetry techniques were applied to the same skulls to estimate the ICV. Anthropometric and cephalometric measurements were carried out directly on skulls and roentgenograms, respectively. Consecutive computed tomography sections at a thickness of 10 mm were used to estimate the ICV of the skulls by means of the point-counting and planimetry methods. The mean (+/-SD) of the actual ICV measured by the water-filling method was 1,262.0 +/- 160.4 cm(3) (1,389.5 +/- 96.5 cm(3) for males and 1,134.5 +/- 94.3 cm(3) for females, respectively). Our results showed that the estimated values obtained by all four methods differed from the actual volumes of the skulls (P < 0.05). The data obtained by anthropometry resulted in overestimation. However, cephalometry, point-counting, and planimetry methods produced underestimation. After calibration, there were no significant differences between the actual volumes and the results of the four methods (P > 0.05). While the anthropometric method is easy and quick to apply, its result may deviate from the actual values. The optimized stereological techniques of point-counting and planimetry methods may provide unbiased ICV results since they take the third dimension of the structures into account.  相似文献   
84.
Sephacryl beads containing an immobilized aminopropylcobalamin- transcobalamin-II complex serve as foci for the adherence of L1210 murine leukemia cells. Bead-cell interaction does not occur when (A) nonderivatized beads are used; (B) transcobalamin-II is omitted or presaturated with cyanocobalamin in the preparation of the bead complex; (C) intrinsic factor replaces transcobalamin-II; and (D) the complex is removed from beads by photolysis. These observations suggest that adherence results from the ability of transcobalamin-II to form a bridge between immobilized cobalamin on the bead and receptors in the plasma membrane of the cell.  相似文献   
85.
The calcium ionophore A23187 promotes histamine synthesis in murine bone marrow cells by increasing the expression of mRNA encoding histidine decarboxylase (HDC), the histamine-forming enzyme. The cells responsible for this biological activity copurify with hematopoietic progenitors in terms of density, light scatter characteristics, and rhodamine retention, similar to interleukin (IL) 3-induced histamine- producing cells. Yet, the effect of calcium ionophore is not mediated by IL-3. The most purified rhodamine-bright bone marrow subset contains 80% cells that respond to calcium ionophore by increased HDC mRNA expression. This high frequency makes the involvement of one particular progenitor subset in histamine synthesis unlikely. The finding that all IL-3-dependent cell lines tested so far exhibit increased histamine production and HDC mRNA expression in response to calcium influx lends further support to this notion. Cell lines requiring other growth factors or proliferating spontaneously lack this ability. Finally, it should be noted that IL-3-dependent cell lines do not produce histamine in response to their growth factor. It might, therefore, be suggested that the pathway transducing the signal for increased histamine synthesis after IL-3 receptor binding in normal hematopoietic progenitors is modified in these cell lines.  相似文献   
86.
Background: ART is steadily performed for infertility cases and most of the previous researches have focused on complicated pregnancies. Nonetheless, few ones have concerned with placenta of ART in non-complicated pregnancies.Objectives: To investigate the expression of angiopoietins (ANG) and their receptor, TIE-2, in placenta of full-term non-complicated pregnancies having ART (n = 28) versus those with spontaneous conception (n = 28) together with the histological as well as morphometric analysis.Results: While no prominent changes were noticed in the histological structure of the placenta ART pregnancies, it showed a significant decrease (p < 0.05) in the percentage of syncytial area and numbers of syncytial knots with insignificant reduction in the placental villous area. Vascular changes in the form of significant decrease (p < 0.05) in the chorionic vessel diameter and significant increase (p < 0.05) in percentage of vessel area were detected in the ART placenta. In addition, the levels ANG-1, ANG-2 and TIE-2 were significantly increased (p < 0.05) in the ART placentas compared with those of SC.Conclusions: We demonstrated that there is an altered expression of angiopoietins accompanying the morphometric changes occurring in placenta of ART pregnancies. These changes may indicate vascular and cellular adaptation mechanism for a potential subclinical hypoxia in placenta of ART even in non-complicated pregnancies.  相似文献   
87.
ObjectiveThe purpose of the study was to differentiate between benign and malignant thyroid nodules using nodule-spinal cord signal intensity and nodule apparent diffusion coefficient (ADC) ratios on diffusion-weighted magnetic resonance imaging (DW-MRI).Materials and MethodsForty-four patients (27 females, 17 males; mean age, 49 years) with nodules who underwent DW-MRI were included in this study. The images were acquired with 0, 50, 400 and 1000 s/mm2 b values. ADC maps were calculated afterwards. Fine needle aspiration biopsies (FNAB) were performed at the same day with DW-MRI acquisition. The diagnosis in patients where malignity was detected after FNAB was confirmed by histopathologic analysis of the operation material. The signal intensities of the spinal cord and the nodule were measured additionally, over b-1000 diffusion-weighted images. Nodule/cord signal intensity (SI) ratios were obtained and the digital values were calculated by dividing to ADC values estimated for each nodule. Statistical analysis was performed.ResultsThe (nodule SI-cord SI)/nodule ADC ratio is calculated in the DW images, and a statistically significant relationship was found between this ratio and the histopathology of the nodules (P<.001). The ratio was determined as 0.27 in benign and 0.86 in malignant lesions. The result of receiver operating characteristic (ROC) analysis was statistically significant, and the area under curve (100%) was considerably high. The threshold value was calculated as 0.56 according to the ROC analysis. According to this threshold value, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy rates for (nodule SI/cord SI)/ADC ratios in differentiating benign from malignant thyroid nodules are calculated as 100%, 97%, 83%, 100%, and 98%, respectively.ConclusionWe have found that (nodule/cord SI)/nodule ADC ratio has the highest values for sensitivity and specificity among the tests defined for characterization of nodules.  相似文献   
88.
ObjectiveOur aim was to evaluate the contribution of diffusion-weighted imaging to the differentiation of hydatid cysts (HCs) from the simple cysts and to the identification of the HC subtypes.Materials and methodsA total of 37 patients were included in this retrospective study. Fifty of these patients had diagnosed liver cysts (28 HCs and 22 simple cysts) of at least 1 cm in size. All of the cysts were examined with sonography and magnetic resonance imaging, and the HCs were classified according to the World Health Organization criteria.ResultsTwenty-eight of the total 50 cysts were HCs, and 22 were simple cysts. When the apparent diffusion coefficient (ADC) values of all HCs were compared with the ADC values of the simple cysts, a statistically significant relationship was found (P=.001). The optimal ADC threshold value was established as 2.5 s/mm2. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy rates were 60%, 95%, 94%, 65% and 76%, respectively.ConclusionDiffusion-weighted imaging–magnetic resonance imaging is a considerably helpful technique for differentiating between HCs and simple cysts and for differentiating between HC subtypes.  相似文献   
89.

Objectives

A wide variety of manifestations is presented in patients with Gaucher''s disease (GD), including bone, haematology and visceral disturbances. This study was conducted to ascertain the main maxillofacial abnormalities by means of clinical survey, panoramic and cone beam CT (CBCT); to compare the patient''s group with an age–sex matched control group; and to correlate clinical and radiological data.

Methods

Ten patients previously diagnosed with GD were submitted to clinical and radiological surveys (CBCT and panoramic radiographs). The examination consisted of anamnesis, extra- and intraoral examinations and analyses of each patient''s records. Imaging data were collected from the point of view of 3 observers, and the results compared with a healthy group (20 individuals) by means of statistical analysis (Fisher''s exact test).

Results

Gaucher patients had significantly more manifestations than otherwise healthy carriers. The most prevalent findings were enlarged marrow spaces, generalized osteopenia and effacement of jaw structures (mandibular canal, lamina dura and mental foramen). Here we describe a case in which thickening of the maxillary sinus mucosa was observed on CBCT rather than opacification of the sinus as seen on panoramic radiographs. Pathological fractures, root resorption and delay on tooth eruption were not observed.

Conclusions

A poor relationship could be observed between clinical and radiological data. Patients showed important bone manifestations, which require careful diagnostic and surgical planning whenever necessary. Although panoramic radiographs have shown significant differences, CBCT is more effective in pointing out differences between patients and a control group, thus showing it as an important tool for evaluation of Gaucher patients.  相似文献   
90.
The early and late results of percutaneous transluminal coronary angioplasty in elderly patients are well known, but although stent implantation has become the most frequent percutaneous coronary intervention in many centers, little information exists about its long-term outcome in elderly patients. The aim of this study was to evaluate the long-term clinical and angiographic follow-up results of intracoronary stenting in a study cohort of 120 patients (92 male) over 65 years of age, who underwent successful coronary stenting between June 1995 and December 1997. The target coronary artery was 48% left anterior descending, 21% circumflex and 31% right coronary artery. Stent implantation was elective in 54%, suboptimal in 32% and bailout in 14% of the patients. Long-term (34+/-14 months) clinical and angiographic follow-up was completed in 78% and 56% of the patients, respectively. The following end-points were considered: death, non-fatal myocardial infarction (MI), target and non-target lesion revascularization. Angiographic restenosis was detected in 31% of the patients. During the long-term follow-up period, 14% of the patients died and 11% developed a new MI. Target lesion revascularization was done in 19.4%, non-target lesion revascularization was done in 21%, and the survival rate was 86%. Although the restenosis rates did not deviate greatly from the expected long-term figures in younger populations, they do indicate that the potential for major cardiac events is still high among elderly subjects, in spite of developments in stent technology and medication.  相似文献   
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