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1.
OBJECTIVE: We aimed to demonstrate the time-dependent ultrastructural changes in pneumocyte type II cells following brain injury, and to propose an electron microscopic scoring model for the damage. METHODS: Forty Wistar-Albino female rats weighing 170-200 g were used. The rats were allocated into five groups. The first group was the control and the second was the craniotomy without trauma. The others were trauma groups. Weight-drop method was used for achieving head trauma. Samples were obtained from the right and left pulmonary lobes at 2-, 8-, and 24-h intervals after transcardiac perfusion. An electron microscopic scoring model was used to reveal the changes. RESULTS: There were no ultrastructural pathological findings pointing to lung injury in any rat of the control groups. There was intense intracellular oedema in type II pneumocyte and interstitial oedema in the adjacent tissue in trauma groups. Oedema in mitochondria and dilatation in both smooth endoplasmic reticulum and Golgi apparatus was more evident in the 8- and 24-h trauma groups. The chromatin dispersion was disintegrated in the nucleus in all trauma groups. Scores of all trauma groups were significantly different from the controls (P<0.05). All trauma groups were different from each other at significant levels (P<0.05 for each trauma groups). CONCLUSIONS: The data suggested that ultrastructural damage is obvious at 2 h and deteriorates with time. The electron microscopic scoring model worked well in depicting the traumatic changes, which were supported by lipid peroxidation. Further experiments are needed to determine the exact outcome after brain death model.  相似文献   
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The aim of this study is to evaluate the effects of low-level laser therapy (LLLT) on (1) the velocity of orthodontic tooth movement and (2) the nitric oxide levels in gingival crevicular fluid (GCF) during orthodontic treatment. The sample consisted of 20 patients (14 girls, six boys) whose maxillary first premolars were extracted and canines distalized. A gallium-aluminum-arsenide (Ga-Al-As) diode laser was applied on the day 0, and the 3rd, 7th, 14th, 21st, and 28th days when the retraction of the maxillary lateral incisors was initiated. The right maxillary lateral incisors composed the study group (the laser group), whereas the left maxillary lateral incisors served as the control. The teeth in the laser group received a total of ten doses of laser application: five doses from the buccal and five doses from the palatal side (two cervical, one middle, two apical) with an output power of 20 mW and a dose of 0.71 J /cm2. Gingival crevicular fluid samples were obtained on the above-mentioned days, and the nitric oxide levels were analyzed. Bonferroni and repeated measures variant analysis tests were used for statistical analysis with the significance level set at p ≤ 0.05. The application of low-level laser therapy accelerated orthodontic tooth movement significantly; there were no statistically significant changes in the nitric oxide levels of the gingival crevicular fluid during orthodontic treatment.  相似文献   
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Calendar     
Despite its long history, there has been very little systematic study of figure skating. Successful skaters and coaches have passed on ideas, traditions, and opinions to their followers with the idea that what once produced good results must be the correct approach. Skaters are significantly shorter, lighter, and leaner than their sedentary counterparts and have a rather low percent body fat. Their cardiovascular fitness levels are 50% to 60% higher than those of sedentary people of the same age, but far less than those of endurance athletes.  相似文献   
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S Provow  G Veli?elebi 《Endocrinology》1987,120(6):2442-2452
Receptors for vasoactive intestinal peptide (VIP) were characterized in rat lung membranes by binding and covalent cross-linking of [125I]VIP using ethylene glycolbis-(succinimidylsuccinate). Binding studies indicated the presence of two classes of binding sites for VIP in rat lung membranes: 0.28 +/- 0.11 pmol/mg protein high affinity receptors (Kd = 79.2 +/- 26.4 pM) and 3.3 +/- 0.9 pmol/mg protein lower affinity receptors (Kd = 4.8 +/- 2.1 nM). Furthermore, binding of [125I]VIP to rat lung receptors was inhibited by micromolar concentrations of GTP analogs, guanosine-5'-O-(3-thiotriphosphate) GTP gamma S), and guanylylimidodiphosphate, suggesting that VIP receptors in rat lung membranes were tightly coupled to the guanine nucleotide regulatory protein (Ns). Scatchard analysis of VIP binding in the presence of GTP gamma S revealed selective inhibition of binding to high affinity sites. A 58K band was specifically labeled when membranes covalently labeled with [125I]VIP were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis under reducing conditions. The apparent size of this species was not altered when sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis was carried out in the absence of reducing agent. Unlabeled VIP inhibited the labeling, with an IC50 of about 1 nM. A related peptide, GH-releasing factor-(1-40)OH, exhibited a much lower binding affinity, and two unrelated peptides, insulin and atrial natriuretic factor, did not inhibit labeling of the 58K species, even at micromolar concentrations. Labeling of the 58K species was inhibited in a GTP gamma S-dependent manner, suggesting the involvement of this species in the coupling to Ns. These data collectively indicated that the 58K species was a VIP-binding unit of VIP receptors in rat lung membranes. Several nondenaturing detergents were tested for extraction of labeled receptors from the membrane; the best extraction was obtained using 1% n-octyl-beta-D-glucopyranoside.  相似文献   
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Objective

Oxidative metabolism is impaired in several medical conditions including psychiatric disorders, and this imbalance may be involved in the etiology of these diseases. The present study evaluated oxidative balance in pediatric and adolescent patients with attention deficit hyperactivity disorder (ADHD).

Methods

The study included 48 children and adolescents (34 male, 14 female) with ADHD who had no neurological, systemic, or comorbid psychiatric disorders, with the exception of oppositional defiant disorder (ODD), and 24 sex- and age-matched healthy controls (17 male and seven female).

Results

TAS was significantly lower, and TOS and OSI were significantly higher in patients with ADHD than in healthy controls. Total antioxidant levels were lower in patients with comorbid ODD than in those with no comorbidity. No difference was found in TOS or OSI among the ADHD subtypes; however, TAS was higher in the attention-deficient subtype.

Conclusion

Our findings demonstrated that oxidative balance is impaired and oxidative stress is increased in children and adolescents with ADHD. This results are consistent with those of previous studies.  相似文献   
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In this multicenter, retrospective study, we evaluated the efficacy and safety of biologic therapies, including anti-TNFs, in secondary (AA) amyloidosis patients with ankylosing spondylitis (AS) and rheumatoid arthritis (RA). In addition, the frequency of secondary amyloidosis in RA and AS patients in a single center was estimated. Fifty-one AS (39M, 12F, mean age: 46.7) and 30 RA patients (11M, 19F, mean age: 51.7) with AA amyloidosis from 16 different centers in Turkey were included. Clinical and demographical features of patients were obtained from medical charts. A composite response index (CRI) to biologic therapy—based on creatinine level, proteinuria and disease activity—was used to evaluate the efficacy of treatment. The mean annual incidence of AA amyloidosis in RA and AS patients was 0.23 and 0.42/1000 patients/year, respectively. The point prevalence in RA and AS groups was 4.59 and 7.58/1000, respectively. In RA group with AA amyloidosis, effective response was obtained in 52.2 % of patients according to CRI. RA patients with RF positivity and more initial disease activity tended to have higher response rates to therapy (p values, 0.069 and 0.056). After biologic therapy (median 17 months), two RA patients died and two developed tuberculosis. In AS group, 45.7 % of patients fulfilled the criteria of good response according to CRI. AS patients with higher CRP levels at the time of AA diagnosis and at the beginning of anti-TNF therapy had higher response rates (p values, 0.011 and 0.017). During follow-up after anti-TNF therapy (median 38 months), one patient died and tuberculosis developed in two patients. Biologic therapy seems to be effective in at least half of RA and AS patients with AA amyloidosis. Tuberculosis was the most important safety concern.  相似文献   
10.
Platelets have the capacity to release mediators with potent inflammatory or anaphylactic properties. Platelet factor-4 (PF4) and beta-thromboglobulin (BTG) are two of these mediators. On the other hand, plasminogen activator inhibitor-1 (PAI-1) and tissue plasminogen activator (tPA) are two important mediators of fibrinolysis. Both mediators are secreted mainly by vascular endothelium. Plasma levels of PF4, BTG, PAI-1, and tPA may show changes in chronic inflammatory diseases such as asthma. This study examined the role of thrombocytes and the function of the endothelium in asthmatic patients during an attack and during a stable phase. Eighteen patients with known allergic asthma who came to our emergency department with an asthma attack and 14 control subjects were included in the study. Blood samples were taken after starting therapy with salbutamol inhalation. Lung function tests were performed after receiving the first emergency therapy for asthma. Plasma levels of PF4, BTG, PAI-1, tPA were determined before starting steroid therapy and after receiving 1 week of steroid therapy. Plasma levels of PF4 among patients with an asthma attack were significantly higher than those of controls (150.5+/-8.92 IU/mL vs. 92.5+/-7.63 IU/mL, p<0.001). A further increase in plasma PF4 levels was detected after steroid therapy (163.5+/-9.16 IU/mL). Plasma BTG levels of patients on admission were not statistically different from those in the control group (140.4+/-6.34 IU/mL vs. 152.2+/-8.71 IU/mL). An increase was detected after therapy (171.6+/-7.27 IU/mL) and post-treatment plasma levels were statistically meaningful versus the controls. Plasma levels of tPA and PAI were statistically higher than those in controls in asthmatic patients on admission (6.01+/-2.72 vs. 5.4+/-2.3 ng/mL for tPA and 75.2+/-27.2 ng/mL vs. 32.7+/-14.3 ng/mL for PAI-1). Further increases were detected in two parameters after 1 week of therapy with steroids (tPA levels were 6.85+/-2.96 ng/mL and PAI-1 levels were 83.5+/-29.6 ng/mL). There seems to be an increased activity of platelets during an asthma attack. Elevated PAI-1 and tPA levels may also indicate the activated endothelium in asthma. Increases of plasma levels of PAI-1 and tPA after steroid therapy need further investigation because elevated PAI-1 levels enhance airway remodeling.  相似文献   
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