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排序方式: 共有2343条查询结果,搜索用时 15 毫秒
1.
Yildiz Oner-Iyido?an Pernur Oner Hikmet Ko?ak Abdul Lama Figen Gürd?l Selda? Bekpinar Nurettin Unur Zeynep Ozbek-Kir 《Pharmacological research》2005,52(4):340-345
Leukocyte arylsulphatase A (AS-A) was shown to be significantly high in newly-diagnosed breast cancer patients. Previous reports imply a connection between serum interleukin-6 (IL-6) and breast cancer, possibly through a modulation of enzymes involved in estrogen synthesis. Abnormal distribution of heparan sulphate proteoglycans (HSPGs) in malignant breast epithelial cells suggests that they play a key role in the regulation of cell growth. Estradiol is believed to be effective in modulating glycosaminoglycans (GAGs) and their depolymerizing enzymes. Therefore, in this study, attempts were made to evaluate the activity of leukocyte arylsulphatase A, serum interleukin-6, urinary GAGs and heparan sulphate (HS) in response to tamoxifen (TAM) therapy in mastectomised breast cancer patients. Thirty-four patients (aged 30-82 years) were administered TAM (20 mg twice daily). Blood and urine samples of each patient were collected three times (at the beginning, and in third and sixth month of TAM therapy), and biochemical parameters were measured. There was no difference between baseline leukocyte AS-A activity and that measured after three months. At the end of six months, enzyme activity was significantly higher than the former values (p=0.022), but within the reference intervals reported in the literature. Although this increase might imply a normalization, the duration of TAM therapy is not long enough to make a decision about either regression or aggravation of the disease. TAM did not have any effect on serum IL-6, urinary HS and GAG levels which may be due to insensitivity of these variables to TAM during the short period of therapy. Both urinary GAG and HS levels measured at sixth month exhibited a positive correlation with the baseline level of leukocyte AS-A (p=0.005 and 0.009, respectively), suggesting that positive responses to the drug might be seen in patients with low AS-A activity. 相似文献
2.
Karahan ZC Atalay F Uzun M Erturan Z Atasever M Akar N 《Microbial drug resistance (Larchmont, N.Y.)》2004,10(4):325-333
Drug-resistant tuberculosis is a serious problem throughout the world. Resistance to Rifampicin (RIF) is mainly caused by the mutations in the rpoB gene coding the beta-subunit of RNA polymerase. In this study, we aimed to detect the distribution of rpoB gene mutations in 80 RIF-resistant clinical Mycobacterium tuberculosis (MTB) isolates from Turkey. The rpoB gene was amplified by PCR and mutations leading to RIF resistance were determined by automated sequence analysis. A total of 72 of the 80 isolates (90%) were found to carry mutations in the amplified region, whereas eight isolates (10%) carried no mutations. Overall, 24 different missense mutations affecting 14 codons, and two deletion mutants were identified. Nine new mutations, six in the hot-spot region and three outside this region, were found. The codon numbers of the most frequently encountered mutations were 531 (51.4%), 526 (18.1%), 516 (13.9%), and 513 (12.5%). As a result, 90% of the RIF-resistant MTB isolates from the Turkish patients were found to carry a mutation in the rpoB gene, Ser531Leu being the most frequent one. Although molecular methods identify mutations leading to RIF resistance very quickly, results of the antimycobacterial susceptibility tests must be taken into consideration for the patients carrying no mutations in this region. 相似文献
3.
Gülfem Celik Ferda Oner Erkekol Sevim Bavbek Berna Dursun Zeynep Misirligil 《Annals of allergy, asthma & immunology》2005,95(1):33-37
BACKGROUND: Cyclooxygenase-2 (COX-2) inhibitors are reported to be well tolerated in patients with analgesic intolerance (AI). However, limited data are available about the long-term tolerability of these drugs. OBJECTIVE: To determine the long-term tolerability of COX-2 inhibitors in patients with Al. METHODS: Patients with AI who previously underwent single-masked, placebo-controlled oral provocation tests and were found to tolerate nimesulide, meloxicam, rofecoxib, or celecoxib were interviewed regarding the long-term use and tolerability of these drugs. RESULTS: Of 87 patients, 61 (70%) had used the recommended COX-2 inhibitor(s). Of the 61 users, 54 (89%) tolerated the drug(s) well and 7 (11%) reported adverse events. Three patients reporting adverse events were rechallenged with the responsible COX-2 inhibitor, and their results were found to be negative. CONCLUSIONS: Long-term use of COX-2 inhibitors was tolerated well by most patients with AI, and placebo-controlled oral provocation tests, as a single test, seemed to predict tolerability. Furthermore, self-reported positive reactions in the long-term should also be confirmed with rechallenge tests for definite diagnosis. 相似文献
4.
5.
Zeynep H. Coban‐Akdemir Wu‐Lin Charng Mahshid Azamian Ingrid S. Paine Jaya Punetha Christopher M. Grochowski Tomasz Gambin Santiago O. Valdes Bryan Cannon Gladys Zapata Patricia P. Hernandez Shalini Jhangiani Harsha Doddapaneni Jianhong Hu Fatima Boricha Donna M. Muzny Eric Boerwinkle Yaping Yang Richard A. Gibbs Jennifer E. Posey Xander H. T. Wehrens John W. Belmont Jeffrey J. Kim Christina Y. Miyake James R. Lupski Seema R. Lalani 《American journal of medical genetics. Part A》2020,182(6):1387-1399
6.
Umut Payza Ahmet Kayali Serkan Bilgin Zeynep Karakaya Fatih Esad Topal 《Asian journal of surgery / Asian Surgical Association》2021,44(6):854-859
Background/Objective: Ischemia is a leading cause of morbidity in Mechanical Intestinal Obstruction (MIO) in which the timing of decisions of whether to proceed to surgical or conservative treatment is critical in emergency departments (ED). While advanced technological options are available, patients may be negatively affected by the application of contrast agents or radiation. The use of ultrasound is limited because of the air in the intestines does not allow a good field of vision. While biomarkers can be considered as a good alternative option at this point. In the present study we examine the effect of hemogram and blood gas parameters on early surgical decision-making in MIO patients.MethodInvolved in this observational prospective study were 264 patients diagnosed with MIO who presented to the Department of Emergency Medicine, Ataturk Research and Training Hospital, Katip Celebi University between February 2018 and February 2019. Contrast-enhanced tomography (CECT) and laboratory results of the patients were recorded. Pathology reports of the patients who underwent surgery were collected. Laboratory data were analyzed by comparing CECT and pathology reports.ResultsIn a ROC analysis of the laboratory values of the patients who were diagnosed with ileus, the sensitivity was calculated as 80% and the specificity was 57.7 in values above WBC>10.75 (109/L), 96.6%, and the specificity was 31.1% in N/L > 2.9. For intestinal ischemia, the cut-off values were WBC> 12.6 and N/L > 3.2, Lactate >2.8 mmol/L and B.E < -3.6 mmol/L.ConclusionDiagnoses of ileus are based on the results examinations and imaging methods. More data are needed to support decisions on the timing of surgery in ED. WBC, N/L, Lactate and Base Excess indicate an ischemic segment. When the parameters are evaluated together, they strongly support early surgical decision-making regarding the treatment of intestinal ischemia. 相似文献
7.
Between 1970 and 1991 the authors examined 466 patients with Eales' disease. The mean age at diagnosis was 30, ranging between 14 and 55 years. The mean follow-up period was 43.5 months. At the initial examination, 356 cases were bilateral and 110 cases were unilateral (822 eyes). Vitreous hemorrhage was present in 257 of the 822 eyes. In the remaining 565 eyes, the major retinal lesions were retinal neovascularization (40.7%), vascular sheathing (20.7%), vascular sheathing and retinal hemorrhages (10.6%), retinitis proliferans (9.4%), disc neovascularization (9.0%), branch vein occlusion (3.2%), tractional retinal detachment (2.4%), central vein occlusion (1.8%), central vascular sheathing (1.1%), obliterated vessels (1.1%). Forty-nine out of the 110 initially unilateral cases eventually developed bilateral involvement after a mean period of 42 months. The percentage of eyes with a vision of 0.1 and better rose from 68.1% in the initial examination to 77.9% in the final examination. Fluorescein angiograms of the affected eyes show dye leakage with retinal staining, microaneurysms, capillary non-perfusion and neovascularization. Fundus changes are characteristic of Eales' disease. Unilateral cases should be closely followed because of the risk of involvement of the other eye. Fluorescein angiography is a requirement for early identification of vascular changes and for proper follow-up in Eales' disease. 相似文献
8.
Between 1970 and 1991 the authors examined 466 cases with Eales' disease. 359 eyes of 295 of these 466 cases received photocoagulation treatment. The mean age was 30.4, ranging between 14 and 55 years. Ten eyes with persistent vitreous hemorrhage underwent pars plana vitrectomy before photocoagulation. 210 eyes were treated with xenon arc, 135 with argon laser, 12 with krypton laser and two with yellow dye laser. Hypoxic areas and retinal neovascularizations were closed completely in 298 eyes. In 21 eyes with elevated neovascularizations intruding into the vitreous cavity feeder vessel photocoagulation was used. 24 eyes with disc neovascularization were treated with panretinal photocoagulation. 12 eyes with branch vein occlusion and four eyes with central vein occlusion received photocoagulation treatment to areas of non-perfusion and retinal neovascularization. At a mean follow-up of 43 months, seven new retinal neovascularizations and three new disc neovascularizations developed in eyes which previously had received photocoagulation for retinal neovascularization and hypoxia. Nine out of 21 eyes with elevated neovascularizations developed vitreous hemorrhage. Disc neovascularization resolved completely in 13 out of 24 eyes, it partially regressed in eight eyes and did not respond to treatment in three eyes. The visual acuities were improved in 12.3%, maintained in 77.4% and deteriorated in 10.3% of the eyes after treatment. Periodic follow-up and early photocoagulation treatment is useful in stabilizing the retinal lesions and in maintaining functional levels of vision in Eales' disease. 相似文献
9.
Leyla S. Atmaca Aysun Idil Deniz Can 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1995,233(12):801-804
Background: Solar retinopathy was observed in a total of 86 eyes of 58 patients following the solar eclipse over Turkey in April 1976. The visual prognosis and the presence of late complications were evaluated at the early and late periods. Methods: Of the 58 patients, 34 (51 eyes) presented during the first week and came for follow-up examination in the succeeding week, also after 1, 3, 12 and 18 months. After that they were examined at yearly intervals (mean 4.2 years). Twenty-four patients (35 eyes) presented during the period between 1 and 11 years post-eclipse and were followed up for a mean period of 3.4 years. After a period of 15 years, all of the patients were invited for re-examination and nine patients (14 eyes) attended. Results: The improvement in visual acuity was observed to have taken place mostly during the first 2 weeks to 1 month after the eclipse. Further improvement in visual acuity was not observed in any of the eyes after the 18-month examination. The improvement in visual acuity was more prominent and earlier in the eyes that had visual acuity of 0.2 or better initially. Only the eyes with initial visual acuity equal to or better than 0.4 had a chance to improve their acuity to 10/10. Having observed the 51 eyes for mean period of 4.2 years and the 35 eyes for 3.4 years, no change in visual acuity was observed. Among the total of 86 eyes, 9 were found to have pseudolamellar macular holes. Conclusion: Correlation was found between initial visual acuity and the funduscopic appearance after the 2nd week. Fluorescein angiography was not found to be a conclusive test in solar retinopathy. No late complications were observed. 相似文献
10.
To understand antioxidant activity and the role played by melatonin, we have designed and tested several new compounds. We
present the results in terms of structure-activity relationships, focusing on the lack of the methoxy group and the influence
of the amide side chain. Antioxidant activity of melatonin and some new melatonin analogue indole derivatives were investigated,
using lipid peroxidation and superoxide anion radical scavenger activity assays, in rat liver tissue homogenate. Most of the
compounds were found to be very potent inhibitors of malondialdehyde (MDA) formation at 10−3M. Inhibition rates ranged from 75-44 %. However, no significant inhibitory effect was obtained on superoxide anion formation.
Consequently, it can be concluded that these compounds exhibit important LP activity compared to melatonin. 相似文献