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91.
92.
In Turkey, "Maras Powder," which is a kind of powder yielded from the shields of tobacco, is widely used as smokeless tobacco through buccal mucosa or together with cigarette. Maras powder, composed of ash and a plant named Nicotiana Rustica Linn, is sometimes used to give up smoking. The present study was aimed to investigate the effects of Maras powder use on respiratory functions of healthy subjects who do not have any chronic disease. We found statistically significant differences in percentage of forced expiratory volume in the first second (FEV(1)%) (p = 0.001), the ratio of FEV(1) to forced vital capacity (FEV(1)/FVC) (p = 0.024), percent of maximum expiratory flow rate (FEF(25-75)%) (p = 0.002) and percent of peak expiratory flow (PEF%) (p = 0.037) between cigarette smokers with Maras powder use (n = 23) and control subjects (n = 24). Likewise, when cigarette smokers (n = 24) and control subjects were compared, the differences for all these parameters were significant (p = 0.022, p = 0.048, p = 0.011 and p = 0.047, respectively). Only FEV(1)% and FEF(25-75)% were significantly lower in cigarette smokers with Maras powder use than in Maras powder users (n = 28) (p = 0.011 and p = 0.022, respectively). There was a negative correlation between forced vital capacity and Maras powder use (r = -0.315, p = 0.03). The present study suggests that Maras powder does not cause serious bronchial obstruction. This may be due to usage of the smokeless tobacco through buccal mucosa but not through inhalation as in case of cigarette smoking.  相似文献   
93.

Objective

The aim of this research was to assess the relationship between mitral annular calcification (MAC) and whole blood viscosity (WBV).

Subjects and Methods

A total of 184 patients with MAC and 133 patients without MAC were enrolled in the study. The WBV was calculated with a confirmed formulation using the hematocrit and total plasma protein at a low shear rate (LSR) and high shear rate (HSR). Early diastolic mitral annular velocity (Ea) and late diastolic mitral annular velocity (Aa) were measured using pulse Doppler tissue echocardiography. Pearson''s correlation analysis was performed to assess the relationship between WBV and mitral annular motion velocities. The effects of different variables on the occurrence of MAC were assessed in univariate and multivariate logistic regression analysis.

Results

In patients with MAC, WBV values were significantly higher at HSR (18.04 ± 0.84 vs. 17.25 ± 0.96 208 s-1, p < 0.001) and at LSR (78.0 ± 14.2 vs. 61.9 ± 17.1 0.5 s-1, p < 0.001). The WBV at HSR and LSR were significantly correlated with Ea (r = −0.477, p < 0.001; r = −0.385, p < 0.001, respectively) and Aa (r = −0.544, p < 0.001; r = −0.323, p < 0.001, respectively). Multivariate analysis showed that WBV of both shear rates was an independent predictor of MAC. Using the ROC curve, a cut-off value of 70.1 for WBV at LSR had a sensitivity of 83.7% and a specificity of 73.7% (AUC 0.785, p < 0.001) and a WBV cut-off value of 17.5 at HSR had a sensitivity of 79.6% and a specificity of 71.4% (AUC 0.761, p < 0.001) for the prediction of MAC.

Conclusion

Patients with MAC had significantly higher WBV, which independently predicted the presence of MAC. WBV had an inverse correlation with mitral annular motion velocities, indicating that a higher WBV may lead to greater limitation in annular motion and, thus, more calcification.Key Words: Mitral valve calcification, Shear stress, Blood viscosity  相似文献   
94.
95.
Hydatid cyst disease is encountered in Turkey frequently. Rupture of a pulmonary cyst into the pleural cavity is rare, but represents the most serious complication of the hydatid disease. Surgical intervention was carried out in all cases in our clinic when expansion of the lungs could not be achieved. Open ends of the bronchus were closed and the pericyst layer was sutured after the removal of the germinative layer. We here present 5 cases of hydatid cysts with the above mentioned complication.  相似文献   
96.
Two-dimensional color Doppler tissue imaging (CDTI) has so far been used, in general, to evaluate ventricular function. This study examined if the left atrial appendage tissue velocity could reproducibly be measured with CDTI and if they have any predictive value for left atrial appendage (LAA) function and former thromboembolism. Thirty-six patients (24 women, 12 men; mean age 45 +/- 12 years; 18 AF; 11 former thromboembolic stroke) with mitral stenosis undergoing transesophageal echocardiography were examined with CDTI. Peak systolic tissue velocity (m/sec, peak systolic velocity [PSV]) was measured at the tip of the LAA in the basal short-axis view. LAA flow emptying (LAAEV) and filling (LAAFV) velocities (m/sec) were also recorded 1 cm immediately below the orifice of the appendage. Interobserver and intraobserver variabilities were determined for the PSV. LAA ejection fraction was measured by Simpson's method. Mitral regurgitation, AF, transmitral mean gradient, left ventricular ejection fraction, mitral valve area, and left atrial diameter were used as a covariant for adjustment. The intraobserver and interobserver correlation coefficients for the PSV using CDTI was 0.64 and 0.60, respectively (bothP = 0.01). LAAEV(0.29 +/- 0.09 vs 0.19 +/- 0.04, P = 0.001)and LAA ejection fraction(44 +/- 12 vs 29 +/- 14, P = 0.004)were found to be significantly decreased in the patients with decreased PSV (<0.05 m/sec), even after adjustment. The decreased PSV was positively correlated with the low LAAEV (<0.25 m/sec) and history of thromboembolism (r = 0.59, r = 0.38, respectively), and remained a significant determinant of the low LAAEV (OR 50.03, CI 1.46-1738.11,P = 0.02), but not of history of thromboembolism (OR 4.29, CI 0.52-35.01,P = 0.08) after adjustment. In conclusion, these results suggest that CDTI provides a reproducible method for quantification of contraction at the tip of the LAA. Decreased PSV may be predictive of poor LAA function.  相似文献   
97.
Vascular endothelial growth factor (VEGF) is known to be involved in the pathogenesis of rheumatoid arthritis (RA). In order to elucidate the association between VEGF levels and RA disease activity, VEGF concentrations were measured in RA patients at different phases and severity levels. Thirty-eight healthy subjects and 40 patients with RA were prospectively included in the study. Subjects were further categorized into four subgroups (high, moderate, low, or remission) using the disease activity score-28 (DAS28) scoring system. VEGF levels were significantly higher in patients than controls (p < 0.001). VEGF levels differed significantly in controls, early and late-phase RA patients (p = 0.002). A significant difference was found between controls and patients with high RA disease activity scores (p < 0.0001). VEGF levels were not correlated with age (r = −0.016; p = 0.921) or sex (r = 0.209; p = 0.921). VEGF values were correlated with erythrocyte sedimentation rate (r = 0.445; p = 0.004), but was not correlated with serum rheumatoid factor levels (r = −0.130; p = 0.424) in the patient group. In conclusion, higher VEGF levels are associated with late phase and high disease activity in RA, independent of age and sex.  相似文献   
98.
OBJECTIVE: In this study, we investigated the relationship between fascioliasis and serum malondialdehyde (MDA) levels, superoxide dismutase (SOD), catalase, and glutathione peroxidase (GPx) activities. We also investigated whether there are significant differences in MDA levels and antioxidant enzymatic activities between acute and chronic fascioliasis. METHODS: Forty fascioliasis patients who were diagnosed by ES-ELISA positivity were included in this study. The patients were classified as 18 with acute and 22 with chronic fascioliasis. RESULTS: In patients with fascioliasis, levels of MDA were statistically higher and erythrocyte SOD and GPx activities were statistically lower than in healthy controls. MDA levels were found to be higher in patients with acute fascioliasis than in patients with chronic fascioliasis although MDA levels were significantly higher in patients with chronic fascioliasis than in controls. There was no statistically significant difference between the two groups for the antioxidant enzyme activities. CONCLUSION: The results of this study may indicate that fascioliasis produces specific effects on the antioxidant defense mechanisms due to its inflammatory character. Our results also allow us to suggest that oxidative stress has an important role in the pathogenesis of fascioliasis and the persistence of this oxidative stress can be one of the underlying factors in the pathogenesis of the chronic disease.  相似文献   
99.
Guanylin-like peptides regulate electrolyte/water transport through the epithelia. Moreover, these peptides possess antiproliferative activity and regulate the turnover of epithelial cells. In an earlier study we localized guanylin immunoreactivity in secretory ducts of adult rodent salivary glands. In this study we investigated the appearance and distribution pattern of this peptide during the development of rat salivary glands. Guanylin immunoreactivity appeared at the beginning of cell differentiation from solid bud, on embryonic day 17 in the submandibular and sublingual glands and after day 18 in the parotid gland. Guanylin immunoreactivity appeared first in ductal and acinar anlage: its cell distribution pattern and fate differed in these two compartments. In the duct cells guanylin immunoreactivity spread after the duct system developed, whereas in acinar cells it disappeared after cell differentiation. The guanylin immunoreactivity we detected in adult salivary duct cells accords with guanylins role in regulating electrolyte and water transport through the various epithelia. It does so by activating guanylate cyclase-C receptor, increasing intracellular cGMP concentration, and phosphorylating the cystic fibrosis transmembrane conductance regulator (CFTR) protein by the cGMP-dependent protein kinase II. This signaling cascade couples to the ductal electrolyte/water secretion and modulates finally the electrolyte composition of the saliva. On the other hand, CFTR is also involved in mechanisms of cell growth, by regulating apoptosis, and promoting cell differentiation. The early diffuse guanylin immunoreactivity we observed in ducts and acinar anlage, before the secretory set is operative, suggests guanylin has a role in cell differentiation.  相似文献   
100.
Image quality in non‐contrast‐enhanced (NCE) angiograms is often limited by scan time constraints. An effective solution is to undersample angiographic acquisitions and to recover vessel images with penalized reconstructions. However, conventional methods leverage penalty terms with uniform spatial weighting, which typically yield insufficient suppression of aliasing interference and suboptimal blood/background contrast. Here we propose a two‐stage strategy where a tractographic segmentation is employed to auto‐extract vasculature maps from undersampled data. These maps are then used to incur spatially adaptive sparsity penalties on vascular and background regions. In vivo steady‐state free precession angiograms were acquired in the hand, lower leg and foot. Compared with regular non‐adaptive compressed sensing (CS) reconstructions (CSlow), the proposed strategy improves blood/background contrast by 71.3 ± 28.9% in the hand (mean ± s.d. across acceleration factors 1–8), 30.6 ± 11.3% in the lower leg and 28.1 ± 7.0% in the foot (signed‐rank test, P < 0.05 at each acceleration). The proposed targeted reconstruction can relax trade‐offs between image contrast, resolution and scan efficiency without compromising vessel depiction. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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