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81.
Ateş A Düzgün N Ulu A Tiryaki AO Akar N 《Pathophysiology of haemostasis and thrombosis》2003,33(3):157-163
OBJECTIVES: Beh?et's disease (BD) is a chronic inflammatory disorder of still unknown etiology, characterized by endothelial cell injury/dysfunction and thrombosis and/or aneurysm of large blood vessels. Thrombophilia may play a role in the pathogenesis of thrombosis in BD. The common inherited gene defects, factor V (FV) 1691A (Leiden) and prothrombin (PT) 20210A, are known risk factors for thrombosis. The FV 4070G polymorphism was shown to influence circulating FV levels and to contribute to the activated protein C resistance phenotype. The aim of the study was to evaluate the role of FV 1691A, FV 4070G and PT 20210A gene mutations in Turkish BD patients with and without venous thrombosis. METHODS: Seventy-one patients with BD (27 with venous thrombosis) and 91 healthy subjects were included in the study. FV 1691A, FV 4070G, and PT 20210A mutations were determined by a method based on PCR-RFLP. RESULTS: The frequency of FV 1691A heterozygous mutation in BD patients with venous thrombosis (25.9%) was significantly higher than that in healthy subjects (8.8%; OR = 3.63; 95% CI 1.18-11.2). Although the frequency of this mutation in patients with venous thrombosis was higher than that in the patients without venous thrombosis (11.4%), the difference did not reach a statistically significant level (OR = 2.73; 95% CI 0.77-9.70). In BD patients with thrombosis, the frequencies of FV 4070G and PT 20210A were not significantly different compared to the BD patients without venous thrombosis and healthy subjects. CONCLUSIONS: Our results suggest that the FV 1691A, FV 4070G, and PT 20210A mutations are unlikely to play an important role in the pathogenesis of thrombosis in patients with BD. 相似文献
82.
Uzuner N Kavukçu S Yilmaz O Ozkal S Işlekel H Karaman O Soylu A Kargi A 《Acta medica Okayama》2002,56(6):295-301
Leukotrienes, one of the mediators of inflammation in asthma, have a strong bronchoconstrictive effect. L-carnitine has been reported to influence respiratory functions. It has also been reported that L-carnitine inhibits leukotriene synthesis. To evaluate the effects of L-carnitine on oxygen saturation, urine leukotriene E4 levels and lung histopathology in a murine model of asthma, high IgE responder BALB/c mice (n = 24) were systemically sensitized to ovalbumin and chronically challenged with low particle mass concentrations of aerosolized ovalbumin, and then they were divided into 3 groups (study groups A, B, and C) each including eight mice. After methacholine-induced bronchoconstriction, the mice in groups A and B were given intraperitoneal L-carnitine (250 and 125 mg/kg, respectively), while the mice in group C were given placebo. Oxygen saturation of the mice was measured by pulse oxymeter before and after methacholine and after L-carnitine/ placebo application. In addition, urine leukotriene E4 levels were measured before asthma development, and 24-h after L-carnitine injection in asthmatic mice. Inflammation in the lung tissues of the sacrificed animals was scored histopathologically to determine the effect of L-carnitine on tissue level. A control group of non-sensitized mice (n = 8) treated with placebo only was used for comparison of urine leukotriene E4 levels and of histopathological parameters. Oxygen saturation of the mice in the study groups tended to decrease after methacholine and to improve after L-carnitine injection, although these changes were not significant at all time points. Urine leukotriene E4 levels of all 3 study groups increased significantly after asthma development. The rate of increment was smallest in the group given the highest L-carnitine dose (group A). Inflammation at the tissue level was also mildest in group A, and severest in the group that was not given carnitine (group C). All of the study groups and the control group differed significantly with respect to inflammation scores. In conclusion, L-carnitine improved oxygen saturation, and decreased urine leukotriene E4 levels and inflammation in lung tissues in the present murine model of asthma. 相似文献
83.
Deniz Eyice Karabacak Semra Demir Osman Ozan Yeğit Ali Can Kadriye Terzioğlu Derya Ünal Müge Olgaç Raif Coşkun Bahauddin Çolakoğlu Suna Büyüköztürk Aslı Gelincik 《Allergy》2021,76(8):2535-2543
Background
Hereditary angioedema (HAE) attacks can be provoked with psychological factors. The aim of this study was to assess the effects of anxiety, depression and stress related to COVID-19 pandemic on disease activity of HAE patients during the quarantine period (QP) and the return to normal period (RTNP).Methods
This study was conducted between March 2020 and September 2020 in four allergy centres. Demographic, clinical features and mental health status were evaluated in QP (from March to the beginning of June) and RTNP (from June to the beginning of September) applied by the government. The 10-point visual analogue scale (VAS10) was used to define the severity of HAE attacks. Depression, Anxiety and Stress Scales-21 (DASS-21) and Fear of COVID-19 (FC-19) scale were performed to assess mental health status.Results
139 HAE patients were included in the study. In QP, median attack numbers and median VAS10 scores were 5 (min-max: 0–45) and 6 (min-max: 0–10), respectively. HAE attack numbers, DASS-21 stress, anxiety, depression and total DASS-21 scores, and FC-19 scores were higher in QP than RTNP (p = 0.001, p < 0.001, p = 0.001, p < 0.001, p < 0.001, p < 0.001, respectively). However, there was no difference in attack severity scores between the two periods (p > 0.05).Conclusions
This study revealed that the restriction measures during COVID-19 outbreak cause an increase in the number of HAE attacks in relation to anxiety, depression, stress and fear of COVID-19 pandemic. Therefore, it is important to provide psychological support to HAE patients during the pandemic.84.
A. Tümer N. Öztürk-Demir C. Basar-Eroglu A. Noyan 《Journal of muscle research and cell motility》1983,4(1):103-113
Summary In this study the spontaneous activities of prescapular lymph nodes, which were isolated from calves, goats and sheep and mesenteric lymph nodes of guinea-pigs were recorded and analysed in the frequency domain. Stretch-evoked contractions of the mesenteric lymph nodes were also recorded and their frequency characteristics analysed.The preparations were placed in a Krebs solution which was kept at 37° C and bubbled continuously with a mixture of 95% O2 and 5% CO2. The tension changes occurring in the lymph nodes were recorded. The patterns obtained were initially transformed into numerical values which were then used to obtain autocorrelation functions and power spectra, according to the time series analysis method. A passive stretch of 100 s duration was applied to the mesenteric lymph nodes and the responses were examined using the transient response-frequency characteristics method.It was observed that prescapular and mesenteric lymph nodes had spontaneous activities due to the contractions of the smooth muscles within the nodes. A frequency analysis of these contractions indicated that at least three contractile components were responsible for the contractions; these components contract within the frequency bands of 0.01–0.04 Hz, 0.05–0.07 Hz and 0.09–0.14 Hz respectively. It was also observed that the spontaneous activities could be regulated and synchronized by stretch. It is suggested that these contractions of the lymph nodes play an essential role in lymph propulsion within the nodes. 相似文献
85.
Comparison of three methods for detection of pneumococcal antigen in sputum of patients with community-acquired pneumonia 总被引:5,自引:0,他引:5
A. Örtqvist I. Jönsson M. Kalin A. Krook 《European journal of clinical microbiology & infectious diseases》1989,8(11):956-961
In a prospective study of 249 patients with community-acquired pneumonia, three tests for the detection of pneumococcal antigen in sputum were compared: a coagglutination test for detecting capsular antigens (Cap-CoA), a sandwich enzyme immunoassay (PnC-EIA) and a coagglutination test (PnC-CoA), both the latter detecting the pneumococcal C-polysaccharide common to all pneumococcal types. Sixty-three patients had culture-positive pneumococcal pneumonia, 45 pneumonia caused by other bacteria and 141 pneumonia of viral or unknown etiology. The sensitivity of Cap-CoA (63%) and PnC-CoA (65%) was somewhat higher than that of PnC-EIA (49%), but not significantly so. The specificity was 96–98% for all three methods. Using PnC-CoA 66 patients with possible pneumococcal infection were detected, the diagnosis being verified by culture in 41. Using Cap-CoA 59 such patients were detected, the diagnosis being verified in 40, and using the PnC-EIA 47 such patients were detected, the diagnosis being verified in 31. Antigen was found almost as often in non-purulent as in purulent samples, and as often in washed as in non-washed purulent samples. However, antibiotic treatment before the sputum sample was obtained resulted in significantly lower sensitivity of both PnC-CoA and Cap-CoA. This study confirms the high sensitivity and specificity of methods for pneumococcal antigen detection in sputum. Since CoA is easier and quicker to perform, and cheaper than the EIA, either PnC-CoA or Cap-CoA would seem to be the technique of choice for detection of pneumococcal antigen, whereby all sputum samples, including non-purulent samples, can be used. 相似文献
86.
Yusuf E. Karakullukçu Tayfun Özçelik Nuran Gökhan 《Pflügers Archiv : European journal of physiology》1987,410(6):657-663
Reperfusion of hearts with a Ca2+-containing medium after a perfusion period in Ca2+-free medium results in irreversible cell damage (calcium paradox). In this investigation we have studied coronary flow and cyclic AMP and cyclic GMP levels after several periods of Ca2+-free perfusion in isolated rat hearts. We also investigated the effects of papaverine (Pap), noradrenaline (NA), acetylcholine (ACh) and absence of inorganic phosphate during Ca2+-free perfusion on coronary flow (CF) and cyclic nucleotide levels. Inability of the heart to recover contractile activity with development of contracture during the reperfusion period was accepted as indicative of the calcium paradox. Ca2+-free perfusion alone and NA and absence of inorganic phosphate during the Ca2+-free perfusion period increased CF, whereas Pap and ACh decreased it. However, only Ca2+-free perfusion and NA elevated cyclic AMP. On the other hand, Pap and ACh increased cyclic GMP (with a transient rise of cyclic AMP in Pap infusion), and absence of inorganic phosphate decreased both cyclic AMP and cyclic GMP. Pap, ACh and absence of phosphate prevented the calcium paradox. Our study suggests that increased cyclic AMP during the Ca2+-free perfusion may contribute, with the other factors, to the occurrence of the calcium paradox. 相似文献
87.
A. Öhlen L. Liudbom W. Staines T. Hökfelt A.C. Cuello J.A. Fischer P. Hedgvist 《Naunyn-Schmiedeberg's archives of pharmacology》1987,336(1):87-93
Summary 1. The distribution and microvascular effects of substance P (SP) and calcitonin gene-related peptide (CGRP) were studied in the rabbit tenuissimus muscle using immunohistochemistry and intravital microscopy. 2. Individual fibers within nerve bundles and along blood vessels in the muscle were found to be immunoreactive (IR) for both SP and CGRP, thus showing an apparently complete coexistence for these peptides. In dorsal root ganglia most SP-positive cells were also CGRP-IR, but the latter cells were somewhat more numerous than SP-IR cells. 3. When applied topically to the muscle, both SP and CGRP increased blood flow in a dose-dependent manner, but CGRP was more potent and caused responses of longer duration. Both SP and CGRP dilated transverse arterioles, but they had little or no effect on the smaller terminal arterioles. This resulted in a redistribution of blood flow to the connective tissue adjacent to the muscle. 4. SP, but not CGRP, elicited vigorous vasomotion in larger arterioles and caused the formation of aggregates of platelets and leukocytes in the venules. Neither flow increase, nor vasomotion or aggregate formation were influenced by pretreatment of the animals with mepyramine, cimetidine or indomethacin. Capsaicin (1 M) had a powerful effect on transverse arterioles resembling that of both SP and CGRP. 5. It is concluded that some of the vascular effects hitherto ascribed to SP on the basis of nerve stimulation and application of capsaicin might, at least in part, be due to release of CGRP.
Send offprint requests to: A. Ohlen, Department of Physiology, Karolinska Institutet, S-104 01 Stockholm, Sweden 相似文献
88.
The dose-dependent effect of acute zimeldine and alaproclate treatment upon the acquisition of two-way and one-way active avoidance in the rat was studied in a single-session and in a repeated-sessions design. Zimeldine (5–20 mg/kg, IP), but not alaproclate, caused disruptions of two-way avoidance acquisition. Acquisition deficits were also caused by citalopram and fluoxetine but not the other antidepressant drugs tested. Zimeldine, but not alaproclate or desipramine, caused a slight but non-significant impairment of one-way active avoidance; neither zimeldine nor alaproclate produced any effects upon fear conditioning and retention testing. The long-term action of p-chloroamphetamine (2×10 mg/kg) antagonised the acute zimeldine effect totally, and chronic treatment with zimeldine (15 days, 1×50 mol/kg) and chlorimipramine (15 days, 2×10 mol/kg) also caused some partial blockade of the two-way avoidance deficit. These data seem to suggest some involvement of serotonin (5-HT) in the observed disruptions of two-way active avoidance caused by acute zimeldine treatment. 相似文献
89.
Özışık Pınar Akdemir Özdener Kubilay Murat Ural Berkan Er Uygur Savaş Ali 《Zeitschrift fur Gesundheitswissenschaften》2022,30(6):1431-1440
Journal of Public Health - Because an increasing number of patients travel internationally to seek medical care, Turkey offers comprehensive and outstanding services under extraordinary conditions... 相似文献
90.