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21.
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   
22.
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   
23.
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   
24.
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   
25.
26.
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   
27.
The effects of a specific copper(I)-chelator, neocuproine (NC), and a selective copper(II)-chelator, cuprizone, on nonadrenergic-noncholinergic transmitter mechanisms in the rat urinary bladder were studied by measuring nerve-evoked contractions of bladder strips and voiding function under urethane anesthesia. After blocking cholinergic and adrenergic transmission with atropine and guanethidine, electrical field stimulation induced bimodal contractions of bladder strips. An initial, transient contraction that was blocked by the purinergic antagonist, suramin, was significantly enhanced by NC (20 and 200 microM applied sequentially) but not affected by cuprizone. The facilitating effect, which was blocked by suramin and reversible after washout of the drug, did not occur following administration of neocuproine-copper(I) complex (NC-Cu). NC (20 microM) significantly increased the second, more sustained contraction, whereas 200 microM decreased this response. These effects of NC on the sustained contractions were not elicited by NC-Cu and not blocked by suramin. The nitric oxide synthase inhibitor, l-nitroarginine, did not alter the responses to NC. NC (20 microM) elicited a marked increase in basal tone of the strips. This effect was less prominent after the second application of 200 microMNC or with NC-Cu treatment or in the presence of suramin. In anesthetized rats, during continuous infusion cystometry, intravesical infusion of 50 microM NC but not NC-Cu or cuprizone significantly decreased the intercontraction interval (ICI) without changing contraction amplitude. The ICI returned to normal after washout of NC. Suramin blocked this effect. These results indicate that NC enhances bladder activity by facilitating purinergic excitatory responses and that copper(I)-sensitive mechanisms tonically inhibit purinergic transmission in the bladder.  相似文献   
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29.
OBJECTIVE: To describe the first ICSI pregnancy achieved with sperm that were immobilized by using a noncontact diode laser. DESIGN: Case report. SETTING: Fertility center. PATIENT(S): A 36-year-old woman who had had primary infertility for 9 years. INTERVENTION(S): Sperm immobilization by using a 1.48-microm wavelength diode laser and subsequent ICSI. MAIN OUTCOME MEASURE(S): Fertilization and cleavage rates and pregnancy. RESULT(S): Transfer of two embryos with minor fragmentation led to a single pregnancy. The patient delivered a healthy baby in week 38 of gestation. CONCLUSION(S): Use of a noncontact diode laser for sperm immobilization may be a useful alternative to the conventional mechanical approach.  相似文献   
30.
OBJECTIVE: To observe the effects of hormone replacement therapy with 2.5 mg/day tibolone for 6 months upon plasma nitrite/nitrate (end products of nitric oxide metabolism) in postmenopausal women. PATIENTS AND METHODS: The study involved 24 healthy postmenopausal women treated with tibolone (2.5 mg/day for 6 months) and 20 postmenopausal women who received placebo. Plasma nitrite/nitrate levels were measured with the Griess reaction. Statistical significance was analyzed by the Mann-Whitney U test and Pearson correlation analysis. RESULTS: The mean baseline concentrations of nitrite/nitrate were similar in both treated and placebo groups. Tibolone treatment decreased plasma nitrite/nitrate levels. CONCLUSIONS: We suggest that because of its androgenic and progestogenic actions, tibolone diminishes nitrite/nitrate levels. Also our data provide evidence for the existence of increased (1/3 of subjects, n = 8) and reduced (2/3 of subjects, n = 16) nitrite/nitrate levels in response to tibolone treatment. Clearly, further studies are necessary to establish a risk/benefit ratio for tibolone in view of its effects on nitric oxide metabolism.  相似文献   
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