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91.
Donmez A Aksu K Celik HA Keser G Cagirgan S Omay SB Inal V Aydin HH Tombuloglu M Doganavsargil E 《Thrombosis research》2005,115(4):287-292
INTRODUCTION: Thrombin activatable fibrinolysis inhibitor (TAFI) is a procarboxypeptidase downregulating plasmin formation, thereby causing a tendency for thrombosis development. Since, Beh?et's disease (BD) is a systemic vasculitis, which is commonly complicated by arterial and venous thrombosis, we aimed to find out plasma TAFI levels in BD, compared with healthy controls. We also searched whether plasma TAFI levels were significantly different between Beh?et's subgroups with and without thrombosis. MATERIALS AND METHODS: In this study, 105 BD patients (M/F: 64/41; mean age 36+/-1 years), followed up by Ege University Rheumatology Department were enrolled. The exclusion criteria were hemophilia, hyperlipidemia, diabetes mellitus, hepatic diseases renal failure, antiphospholipid positivity, oral contraceptive use and pregnancy. Age-and sex-matched healthy controls (n=53) were also included. Plasma TAFI levels were measured by ELISA. Since TAFI is also an acute-phase reactant, we also measured other inflammatory markers such as C-reactive protein (CRP). RESULTS: Plasma TAFI levels were significantly higher in Beh?et's patients (91.1+/-7.4 ng/ml) compared with healthy controls (14.3+/-4.5 ng/ml) (P<0.001), but there were no significant difference between the subgroups with and without thrombosis. In BD, there was no correlation between plasma TAFI levels and CRP. CONCLUSIONS: Regardless of manifest thrombosis, plasma TAFI levels in BD were significantly higher than in healthy controls. High TAFI levels might possibly contribute to the thrombotic tendency in BD. Future studies investigating TAFI gene polymorphism and functional activity are clearly needed, to clarify the exact role of TAFI in Beh?et's thrombosis. 相似文献
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93.
In order to determine whether nicotine acts on corporal smooth muscle, the mechanism of its effect on strips of rabbit corpus cavernosum was studied in vitro. Rabbit corpus cavernosum muscle strips were mounted in an organ bath with modified Krebs-Henseleit solution and aerated with 95% O2 and 5% CO2. Tension was measured with isometric force transducers, and muscle relaxation was expressed as the percent decrease of precontraction induced by phenylephrine. Nicotine produced concentration dependent relaxation when preparations were precontracted by phenylephrine (10–5 M). The maximum nicotine-induced relaxation was 60.4±4.2% of the phenylephrine contraction and was not affected by indomethacin (10–5 M), Nw-nitro L-arginine methyl ester (3×10–5 M), methylene blue (10–5 M), glibenclamide (10–5 M), clotrimazole (10-6 M), tetraethylammonium (3×10–4 M), or 4-aminopyridine (10–3 M). Nicotine did not exhibit a calcium antagonizing effect. From these results, we conclude that nicotine-induced relaxation of the rabbit corpus cavernosum is not mediated by the release of nitric oxide, prostaglandins or a related substance, by the activation of potassium channels, or by the stimulation of nicotinic cholinoceptors. Further work is needed to determine the cellular mechanism(s) of the action by which nicotine acts on corporal smooth muscle. 相似文献
94.
Kaya TT Koyluoglu G Karadas B Yildiz T Bagcivan I Ceran C Gökgöz S 《The Journal of surgical research》2004,120(2):219-224
BACKGROUND: The mechanisms involved in the impaired gallbladder contractile response in peritonitis are unknown. The aim of this study was to determine the effect of peritonitis on the contraction and relaxation responses to different agonists in gallbladder smooth muscle in guinea pig. MATERIALS AND METHODS: Peritonitis was induced by cecal ligation and puncture (CLP) in 10 guinea pigs. Another group of 10 guinea pigs underwent a sham operation and acted as controls. Twenty-four hours after the operation, the guinea pigs were killed, and gallbladder strips were placed in organ bath. The contraction responses to KCl, carbachol, and histamine, and relaxation responses to cyclooxygenase inhibitors (indomethacin, nimesulide, and DFU) on KCl-induced contractions were recorded. RESULTS: There was no significant difference between the contractile responsiveness to KCl, but maximum contractile responses (E(max)) to carbachol and histamine were significantly reduced. Indomethacin, nimesulide, and DFU concentration dependently inhibited on KCl-induced contractions of gallbladder smooth muscle. E(max) values of indomethacin, nimesulide, and DFU were significantly reduced in the peritonitis group compared with controls (P < 0.05). The inhibitor effects of nimesulide and DFU were considerably similar, but inhibitor effect of indomethacin was significantly less than that measured for nimesulide and DFU in both control and peritonitis groups (P < 0.05). CONCLUSIONS: The contraction responses to carbachol and histamine and relaxation responses to COX inhibitors on gallbladder smooth muscle are significantly decreased by peritonitis. Although the mechanism of the decrease in contraction and relaxation responses in CLP-induced peritonitis is completely unknown, we speculate that impaired smooth muscle responses may be related to an alteration in the regulation of receptor/postreceptor excitation-response coupling and/or through changes on Ca(2+) influx. 相似文献
95.
Haciibrahimoglu G Fazlioglu M Olcmen A Gurses A Bedirhan MA 《The Journal of thoracic and cardiovascular surgery》2004,127(5):1361-1365
BACKGROUND: The purpose of this study was to estimate operative risk and to identify indicators of adverse prognosis in patients undergoing resection for childhood bronchiectasis. METHODS: From January 1985 to February 2001, patients undergoing resection for bronchiectasis were studied. The indications for operation were failure of medical therapy in 33 patients (94.2%) and hemoptysis in 2 (5.7%). The mean duration of symptoms was 4.2 years (range, 1-9 years). Surgical treatment included lobectomy in 17 patients (48.5%), pneumonectomy in 7 (20%), lobectomy plus segmentectomy in 5 (14.2%), bilobectomy in 2 (5.7%), and segmentectomy in 4 (11.4%). RESULTS: The operative mortality rate was 2.8%, and the morbidity rate was 17.6%. The mean follow-up in 34 patients was 5.4 years (range, 1-12 years). Overall, 22 patients (64.7%) were asymptomatic after surgery. Clinical improvement was noticed in 8 patients (23.5%), and no improvement was noticed in 4 (11.7%). Complete resection resulted in a significantly better clinical outcome than incomplete resection (P <.05). CONCLUSIONS: Surgery for childhood bronchiectasis can be performed with low mortality and morbidity. Complete resection should be performed when possible. 相似文献
96.
The hypotension evoked by visceral nociception is mediated by delta opioid receptors in the periaqueductal gray 总被引:2,自引:0,他引:2
This study tested the hypothesis that the ventrolateral column of the midbrain periaqueductal gray (vlPAG) region mediates the hypotension and bradycardia evoked by visceral nociception. To test this, the local anesthetic lidocaine (2%; 0.5 microl) was microinjected into the vlPAG of halothane-anesthetized rats bilaterally and visceral nociception was induced 2 min later by injecting 5% acetic acid (0.5 ml) intraperitoneally. Acetic acid injection caused an abrupt fall in arterial pressure (-12.2+/-2.1 mm Hg) and heart rate (-37+/-93 bpm) lasting approximately 15 min. Lidocaine injection into the vlPAG prevented the fall in arterial pressure and heart rate completely. Cobalt chloride (5 mM; 0.2 or 0.5 microl) injection into the vlPAG also prevented nociceptive hypotension but it did not affect the fall in heart rate significantly. Lidocaine pretreatment also inhibited the depressor response caused by intramuscular formalin (5%; 0.2 ml) administration, a model of deep somatic nociception, although it did not prevent the response completely. To determine if opioid receptors mediate the response, selective mu, delta or kappa opioid receptor antagonists were microinjected into the vlPAG 5 min before intraperitoneal (ip) acetic acid administration. Naltrindole, a delta receptor antagonist, inhibited the response significantly but mu and kappa antagonists were completely ineffective. Lidocaine and naltrindole had no effect when injected into the dorsolateral PAG and did not influence cardiovascular function when injected into the vlPAG of saline treated control animals. These data support the hypothesis that the vlPAG mediates the depressor response evoked by visceral nociception and indicate that delta opioid receptors participate in the response. 相似文献
97.
Guz H Doganay Z Ozkan A Colak E Tomac A Sarisoy G 《Journal of psychosomatic research》2004,56(3):287-291
OBJECTIVE: There is a difference in classification of conversion disorder in ICD-10 and DSM-IV. Conversion disorder is included in dissociative disorders in ICD-10. In view of this, we aimed to clarify this discrepancy in the classification of this diagnosis. METHODS: We assessed 87 patients with conversion disorder and 71 patients with somatization disorder for sociodemographic characteristics, suicide ideation, psychiatric symptoms and dissociative symptoms using the Patient Information Form, the Dissociative Experience Scale (DES), the Symptom Check List (SCL-90-R) and the Suicide Ideation Scale. RESULTS: The number of the high school graduates, singles and students with conversion disorders was higher than the number of patients with the same characteristics who have somatization disorder. In conversion disorder, the SCL-90-R total score and the score in paranoid ideation, psychoticism subgroups were higher than the scores in somatization disorders. There were no statistical differences in suicide ideation and the total score of dissociative symptoms between the two disorders. The number of patients whose total DES score of 30 and above was higher in conversion disorders. DISCUSSION: As a result of this present study, we concluded that to enlighten the concepts of conversion, further somatization and dissociation studies are necessary. 相似文献
98.
Ozdemir M Bakaris S Ozdemir G Buyukbese MA Cetinkaya A 《Canadian journal of ophthalmology. Journal canadien d'ophtalmologie》2004,39(5):526-532
BACKGROUND: Ocular surface changes, mainly squamous metaplasia of the conjunctival epithelium and corneoconjunctival calcification of unknown etiology, may develop in patients with chronic renal failure undergoing hemodialysis. An association between squamous metaplasia and corneoconjunctival calcification has been suggested. The purpose of this study was to investigate the relation between ocular surface disorders and tear function changes in patients with chronic renal failure undergoing hemodialysis. METHODS: In this prospective case-control study, 42 patients with chronic renal failure and 20 age- and sex-matched control subjects underwent full ophthalmologic examination, tear function tests (including Schirmer's test, tear film break-up time [BUT] test and rose bengal staining) and impression cytology to determine the degree of conjunctival squamous metaplasia. They also responded to a questionnaire regarding subjective ocular complaints. Corneoconjunctival calcification was graded on a scale of 0 to 5 according to the system proposed by Porter and Crombie. Impression cytology samples were graded on scale of 0 to 3 according to the Nelson classification. The relation between ocular surface disorders and tear function changes was evaluated. RESULTS: Of the 42 patients, 12 (28%) had grade 0 calcification, 10 (24%) had grade 1, 14 (33%) had grade 2, and 6 (14%) had grade 3 or higher. Four patients (10%) had grade 0 squamous metaplasia, 22 (52%) had grade 1, 12 (28%) had grade 2, and 4 (10%) had grade 3. The difference between the patient and control subjects in squamous metaplasia grades and corneoconjunctival calcification grades was statistically significant (p < 0.001 and p = 0.022 respectively). Abnormal tear film BUT (p = 0.002) and abnormal rose bengal staining (p = 0.023) were significantly more frequent in the patient group than in the control group. The grade of conjunctival squamous metaplasia was correlated with abnormal rose bengal staining (tau = 0.79, p < 0.001) and with the existence of subjective ocular complaints (tau = 0.32, p = 0.026). There was no correlation between corneoconjunctival calcification and tear function changes. INTERPRETATION: Abnormal rose bengal staining and the presence of subjective ocular complaints may be used as follow-up criteria for ocular surface disorders in patients with chronic renal failure regularly undergoing hemodialysis. 相似文献
99.
100.
Retroperitoneal benign schwannoma: report of three cases and analysis of clinico-radiologic findings
Dede M Yagci G Yenen MC Gorgulu S Deveci MS Cetiner S Dilek S 《The Tohoku journal of experimental medicine》2003,200(2):93-97
Retroperitoneal schwannoma is a rare tumor that originates in the neural sheath and accounts for only a small percentage of retroperitoneal tumors. Presentation is typically varied and non-specific ranging from abdominal pain, abdominal mass or an incidental finding and the diagnosis is quite often fortuitous being confirmed by anatomopathological study afterwards. We report 3 cases of benign retroperitoneal pelvic schwannoma with varied presentations. Main symptoms were abdominal and pelvic pain whereas a patient with left parailiac mass had urinary incontinence and left lower extremity pain. Surgical exploration and complete excision of tumors were successful. The histological diagnosis of the tumors was reported as benign schwannoma. All patients are doing well and had no symptoms of motor or sensory disturbances after surgery with a mean follow up of 18 mounts. 相似文献