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21.
OBJECTIVES: The role of estrogens in human bladder cancer still remains to be resolved. This study was undertaken to determine the estrogen receptor (ER) expression status and to elucidate the prognostic significance of ER in superficial transitional cell carcinoma (TCC) of the human bladder. METHODS: Tumor tissue blocks which were obtained by transurethral resection (TUR) from 121 patients with superficial TCC and 30 control subjects were investigated. Median follow-up was 40 months. The expression of nuclear ER was evaluated by immunohistochemistry using avidin-biotin-peroxidase method and a monoclonal ER antibody. ER staining intensity in samples was assessed semi-quantitatively. Staining characteristics were compared with the clinico-pathological results. RESULTS: ERs were detected in 12.4% of the superficial TCC patients and in 10% of the controls (P = 0.73). No association was found between ER immuno-reactive score and patients' age, sex, tumor multiplicity or tumor size. An association between the ER staining intensity and higher tumor grade was observed (P = 0.01). Grades I, II and III tumors showed 10.6, 8.7 and 44.4% staining, respectively. Survival was not affected by ER expression. In multivariate analysis ER expression was not an independent prognostic factor. CONCLUSION: Superficial TCC of the bladder shows low ER expression and it appears that ERs do not have any direct role on the prognosis of patients with superficial TCC.  相似文献   
22.
OBJECTIVE: The object of this study was to investigate the genotoxic effect of acute overexposure to combustion products originating from coal or wood stoves in patients presenting with acute carbon monoxide intoxication. STUDY DESIGN: In a prospective study, we analyzed the frequency of sister chromatid exchange and the carboxyhemoglobin concentration in 20 consecutive patients without a history of smoking or drug use who had been treated in the Emergency Care Unit of Istanbul Medical Faculty due to acute carbon monoxide intoxication. All of these cases were domestic accidents due to dysfunctioning coal or wood stoves. The results were compared with a control group of 20 nonsmoking, nondrug-using healthy individuals matched for age, sex, and absence of other chemical exposure. RESULTS: The mean sister chromatid exchange frequency per metaphase was significantly higher in the study group compared to the control group: 8.11 +/- 2.39 vs. 6.33 +/- 1.60 (p = 0.008). We found that there was no positive correlation between the blood carboxyhemoglobin concentration and sister chromatid exchange frequency. CONCLUSIONS: These results suggest that acute exposure to combustion products of wood or coal is genotoxic to DNA. Potential causes of genotoxicity include known mutagenic compounds present in coal or wood smoke and ash, oxygen radicals formed during combustion, as well as hypoxic and reperfusion injury mechanisms initiated by carbon monoxide intoxication. Additional studies on separate carbon monoxide exposure from smoke and ash are needed to understand individual genotoxic contributions and mechanisms.  相似文献   
23.
OBJECTIVE: Familial benign prostatic hyperplasia (BPH) is a recently popularized entity with yet uncertain clinical and pathological features. In the present study we investigated whether there was any difference between clinical characteristics of familial and sporadic BPH in a series of 148 surgically treated BPH patients. MATERIALS AND METHODS: A retrospective analysis was performed in 148 patients subjected to transvesical or transurethral prostatectomy to determine the clinical features of familial BPH. Patients were categorised as having familial BPH when 3 or more (including the patient) first-degree family members gave a history of BPH. Accordingly 23 cases who fit this criterion were accepted as having familial BPH and the rest of the cases were taken as the control group. The two groups were compared with respect to age, International Prostate Symptom Score (IPSS), quality of life score, prostate specific antigen (PSA), maximum urinary flow rate and the weight of the surgical prostate specimen. RESULTS: The mean age, IPSS, quality of life score, total PSA, maximum urinary flow rate and the weight of the surgical prostate specimen were found as 65.13 +/- 5.51 years, 23.13 +/- 4.82, 4.78 +/- 0.95, 6.0 +/- 4.1 ng/ml, 6.9 +/- 2.7 ml/s and 62.96 +/- 38.76 g, respectively, in the familial BPH group whereas the same parameters were measured as 68.13 +/- 7.68 years, 24.74 +/- 3.73, 4.52 +/- 0.85, 5.93 +/- 4.75 ng/ml, 4.6 +/- 1.71 ml/s and 70.87 +/- 53.21 g, respectively. No significant difference was present between familial and sporadic BPH cases in any of the studied parameters. CONCLUSION: The clinical features of familial BPH did not differ significantly from those of sporadic BPH.  相似文献   
24.
Proprioceptive mechanisms appear to play a role in stabilizing the joints and may serve as a means for interplay between static stabilizers and dynamic muscular restraints. The purpose of our study was to investigate whether or not gymnastic training has any effect on the balance and on proprioception in an ankle, as seen in gymnasts and in nongymnasts. We evaluated the proprioceptive ability of the ankle using four different tests (a one-leg-standing test, a single-limb-hopping test, an active angle-reproduction test, and a passive angle-reproduction test). Proprioception of the ankle was measured in 40 subjects who were assigned to two experimental groups. Group 1 (n: 20) were healthy control subjects, and group 2 (n: 20) were teenaged female gymnasts. The sense of position of a joint was actively measured using a Cybex NORMTM isokinetic dynamometer and measured passively with a proprioception-testing device. A Mann-Whitney U test was used to compare mean values of the gymnasts to the controls. Results revealed statistically significant differences (p<0.05) between two groups. We found no statistically significant differences between the dominant and nondominant ankle in volunteers or in gymnasts, in all tests. The results of this study suggest that gymnastic training has a positive influence on sense of position of the ankle joint and on balance, in addition to increasing muscle tone.  相似文献   
25.
The aim of this prospective study is to evaluate the effectiveness of combined use of histopathology with cytology in biopsies of the larynx. Biopsies taken for this purpose are studied by using two different methods and the results are evaluated. One hundred and thirty-five patients with suspected malignant laryngeal lesions were examined by direct microlaryngoscopy for primary diagnosis. Each lesion was biopsied first. Subsequently touch smear cytology was obtained from the biopsies. In all cases, cytologic slides (one or two per biopsy) were screened and compared to corresponding biopsies. Lesions were categorized as benign, laryngeal intraepithelial neoplasia and malignant. Results obtained were compared with surgical samples obtained from patients who have undergone surgery. In other cases, where surgery was not applied, results of the follow-up were evaluated. In larynx biopsies the results for histopathology were as follows: sensitivity 93.9%, specificity 100% and accuracy 96.3%. The results for cytology were as follows: sensitivity 82.5%, specificity 94.5% and accuracy 87.4%. A comparison of cytologic evaluation versus histopathologic evaluation in laryngeal biopsies reveals that histopathology is superior. According to the study results, in 88.9% (120/135) of the cases the agreement between cytological and histopathological results was found. In two other cases (1.5%) cytologic evaluation contributed to the histopathologic diagnosis.  相似文献   
26.
Effects of tibolone on thromboxane B(2) levels in postmenopausal women.   总被引:1,自引:0,他引:1  
This study was carried out in 16 premenopausal (control) and 24 postmenopausal women (study group) to investigate the effect of menopause and tibolone treatment (2.5 mg/day for 6 months) on plasma thromboxane B(2) (TxB(2)), a well-known vasoconstrictor and stimulator of platelet aggregation. The TxB(2) levels were measured using [(125)I] RIA kit. Statistical significance was analyzed by Student's t test for paired and unpaired data, and Pearson's correlation analysis. Plasma TxB(2) concentrations of postmenopausal women were higher than those of premenopausal women. Tibolone treatment decreased plasma TxB(2) in postmenopausal women. There was no correlation between TxB(2) and blood pressure and heart rate. It was concluded that tibolone, decreasing the plasma concentrations of TxB(2), might have beneficial effects on prostaglandin metabolism and thus reduce the risk of cardiovascular disease.  相似文献   
27.
Effects of the specific copper (I) chelator, neocuproine, on the purinergic and adrenergic components of nerve-evoked contractions were investigated in the prostatic rat vas deferens. Electrical field stimulation (EFS; 4 Hz) induced bimodal contractions of vas deferens tissue in the presence of alpha1-adrenoceptor antagonist prazosin (to isolate the purinergic component) or purinoceptor antagonist suramin (to isolate the adrenergic component). Neocuproine significantly potentiated the purinergic component of the contractile responses to EFS. However, the same agent failed to elicit any significant effect on the adrenergic component of nerve-evoked contractions. The copper (II) chelator cuprizone could not affect the purinergic component of contractions. The potentiating effect of neocuproine which was reversible after washout of the drug, did not occur following the application of the pre-prepared neocuproine-copper (I) complex. A nitric oxide synthase inhibitor, L-nitroarginine; a cyclooxygenase inhibitor, indomethacin or an alpha2-adrenoceptor antagonist, yohimbine, failed to alter the responses to neocuproine on the purinergic component of the contraction to EFS. Neocuproine did not elicit any significant effect on preparations in which the purinergic receptors were desensitized with alpha,beta-methylene ATP. In conclusion, our results suggest that neocuproine potentiates the purinergic component of rat vas deferens contractions elicited by EFS, presumably by facilitating purinergic neurotransmission and that copper (I)-sensitive mechanisms can modulate purinergic transmission in this tissue.  相似文献   
28.
29.
Tomak Y  Kocaoglu M  Piskin A  Yildiz C  Gulman B  Tomak L 《Injury》2005,36(5):635-643
Forty-two geriatric patients who had an intertrochanteric fracture were treated with a semicircular modification of the Ilizarov frame designed by Cattaneo and Catagni between January 1997 and September 2001. Twenty-five of the patients were female, 17 male. The average age of the patients was 77.5 years (range, 63-99). No intraoperative complication occurred. Deep pin-track infection was found in four patients and varus deformity was observed in two patients and shortening of less than 2 cm in 10 patients. Fixator removal was achieved in a mean time of 12 weeks (range, 10-18). No implant failure, refracture or stiffness of knee and hip joint movements was recorded. We concluded that the treatment of intertrochanteric fractures of the elderly patients with our modification provides significant advantages such as minimal operative and anaesthetic risks, no blood loss, early weight-bearing, short hospitalisation time and rapid union time.  相似文献   
30.
PURPOSE: Serum prostate-specific antigen (PSA) has a restricted predictive value for prostate cancer in the low-intermediate PSA range (2.5-10 ng/ml). Our aim was to determine the predictive value of the International Prostate Symptom Score (IPSS) for positive prostate needle biopsy (PNB) in patients who underwent transrectal ultrasound (TRUS)-guided prostate biopsy with a low-intermediate PSA level. PATIENTS AND METHODS: Between 2001 and 2004, the data of 389 consecutive patients applying for any urologic complaint to our department and who underwent TRUS-guided prostate biopsy due to an elevated serum PSA and/or abnormal digital rectal examination (DRE) were retrospectively analyzed. A total of 158 eligible patients with a low-intermediate PSA level were included in the study. The patient's age, PSA, free PSA, free/total PSA, prostate volume, PSA density (PSAD), pre-biopsy IPSS were compared in the positive and negative biopsy groups. RESULTS: Fifty-eight of 158 patients (37%) who underwent TRUS-guided prostate biopsy had positive PNBs. Forty-eight patients (30%) had abnormal DREs. In the positive PNB group, the mean age was older and PSAD was higher, but the means of the prostate volumes and total IPSS were lower (p<0.05). Multivariate analysis demonstrated that age and IPSS were independent predictors of a positive PNB (p<0.05). The odds ratio of mild IPSS for positive PNB controlled for age was 3.0 (95% CI 1.5-6.7). Receiver-operating characteristics analysis revealed a mild IPSS (AUC=0.640) and was a considerable predictor for positive PNB as well as PSAD (AUC=0.648). The sensitivity and specificity of IPSS with a cutoff value of 7.5 points were 31 and 87% for prediction of prostate cancer detection. CONCLUSION: In the low-intermediate PSA range, mild IPSS may be a predictive factor for positive PNB with a similar specificity of PSAD.  相似文献   
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