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51.
1. Screening intervals according to Tabar: 1 year in women younger than 50 in order to minimize "interval cancers". 2 years in women older than 50 years. 2. Mammographic views according to Lundgren et al: 2 views at first round 1 oblique view in the following rounds, yearly. All women on risk should attend screening. The identification of useful "high risk groups" is not established. Palpation is recommended at each screening. Self-examination is recommended. Adjuvant therapy should not depend on lymph node status in screening-cancer cases. It should depend on clinical and histological "prognostic factors".  相似文献   
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The involvement of adenosine A(1) and A(2A) receptors in the motor effects of caffeine is still a matter of debate. In the present study, counteraction of the motor-depressant effects of the selective A(1) receptor agonist CPA and the A(2A) receptor agonist CGS 21680 by caffeine, the selective A(1) receptor antagonist CPT, and the A(2A) receptor antagonist MSX-3 was compared. CPT and MSX-3 produced motor activation at the same doses that selectively counteracted motor depression induced by CPA and CGS 21680, respectively. Caffeine also counteracted motor depression induced by CPA and CGS 21680 at doses that produced motor activation. However, caffeine was less effective than CPT at counteracting CPA and even less effective than MSX-3 at counteracting CGS 21680. On the other hand, when administered alone in habituated animals, caffeine produced stronger motor activation than CPT or MSX-3. An additive effect on motor activation was obtained when CPT and MSX-3 were coadministered. Altogether, these results suggest that the motor-activating effects of acutely administered caffeine in rats involve the central blockade of both A(1) and A(2A) receptors. Chronic exposure to caffeine in the drinking water (1.0 mg/ml) resulted in tolerance to the motor effects of an acute administration of caffeine, lack of tolerance to amphetamine, apparent tolerance to MSX-3 (shift to the left of its 'bell-shaped' dose-response curve), and true cross-tolerance to CPT. The present results suggest that development of tolerance to the effects of A(1) receptor blockade might be mostly responsible for the tolerance to the motor-activating effects of caffeine and that the residual motor-activating effects of caffeine in tolerant individuals might be mostly because of A(2A) receptor blockade.  相似文献   
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PURPOSE: Both the retinoblastoma and p53 pathways are often genetically altered in human cancers and their complex regulation is in part mediated by the three gene products p16, p14(ARF), and p15 of the INK4 locus on chromosome 9p21. Partial or complete biallelic deletions of the INK4 locus have been recognized in a variety of malignant tumors, including malignant melanoma. We have in the present study measured the frequency of INK4 deletions in a large number of melanoma metastases and determined their association with clinicopathologic variables and survival data. EXPERIMENTAL DESIGN: Quantitative real-time PCR, as well as fluorescence-based fragment analysis, has been used to perform measurements of the relative allelic concentrations of the INK4 genes in 112 human melanoma tumor samples from 86 patients. RESULTS: Thirty-eight of 86 melanoma patients (44%) had metastases with biallelic losses in INK4. Ten of 20 patients with multiple metastases showed similar deletion patterns in all analyzed tumors. There was no significant association between any of the clinicopathologic variables and loss of INK4. However, loss of INK4 had an adverse effect on median survival from time of diagnosis. Patients with tumors with diploid INK4 had a median survival of 142 months, whereas those with monoallelic or biallelic loss in INK4 had a median survival of only 47 months (P = 0.006). CONCLUSIONS: Our results point to homozygous deletions in the INK4 region as being one of the most common genetic alterations in malignant cutaneous melanoma. INK4 deletions are associated with an adverse prognosis.  相似文献   
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The influence of cochlear implantation on some voice parameters   总被引:2,自引:0,他引:2  
OBJECTIVE: Some of the voice characteristics of deaf people differ considerably from those of speakers with normal hearing. After a cochlear implantation, auditory control of voice production is possible and the quality of the voice is improved. The aim of this study was to investigate the changes in some of the voice parameters in deaf children after cochlear implantation. METHODS: Thirty-one prelingually deafened children implanted unilaterally at the age of 2.5-13 years were included in the study. For all of the children an acoustic analysis (Multi-Dimensional Voice Program, Kay Elemetrics Corp., USA) of the Slovene vowel 'a' was performed before cochlear implantation and 6, 12 and 24 months after the implantation. The fundamental frequency (F0), jitter, shimmer and noise-to-harmonic ratio (NHR) were compared before and after the implantation. The results of the acoustic analyses were compared for the children who were implanted before or at the age of 4 years and the children who were implanted after the age of 4 years. RESULTS: After the cochlear implantation the fundamental frequency did not change significantly. However, an improvement was noticed in the measurements of jitter (p=0.006) and shimmer (p=0.021) as early as 6 months after the implantation. The noise-to-harmonic ratio improved (p=0.013) 24 months after the implantation. The children implanted before or at the age of 4 years showed a significant improvement in jitter (p=0.003) and shimmer (p=0.004) as early as 6 months and in noise-to-harmonic ratio (p=0.021) 12 months after the implantation. In the children implanted after the age of 4 years the only significant change was detected in F0 (p=0.045), 12 months after the implantation, and in Shimmer (p=0.017), 24 months after the implantation. CONCLUSION: The results of the present study have confirmed that cochlear implantation enables auditory moment-to-moment control of pitch and loudness. The determination of jitter and shimmer in the vowel 'a' sample proved to be a good and early indicator of improved phonation control, even in young children. The deaf children who were implanted before the age of 4 years improved their voice control more quickly and to a greater extent than the children implanted after the age of 4 years.  相似文献   
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Spermatozoa selection at high magnification before intracytoplasmic sperm injection seems to be positively associated with pregnancy rates after day 3 embryo transfers. The aim was to demonstrate an association between the presence of vacuoles in sperm nuclei and the competence of embryos to develop to day 5. Grading of spermatozoa at x 6000-x 12,500 magnification: grade I, no vacuoles; grade II, or=1 large vacuole; grade IV, large vacuoles with other abnormalities. The outcome of embryo development in a group of 25 patients after sibling oocyte injection with the four different grades of spermatozoa showed no significant difference in embryo quality up to day 3. However, the occurrence of blastocyst formation was 56.3 and 61.4% with grade I and II spermatozoa respectively, compared with 5.1% with grade III and 0% with grade IV respectively (P < 0.001). Spermatozoa selection at high magnification using Nomarski interference contrast is useful to identify more precisely the size and the number of nuclear vacuoles that greatly exert a negative effect on embryo development to the blastocyst stage. These observations confirm previous studies pointing to possible 'early and late paternal effects', both of which may have an impact on early embryonic development.  相似文献   
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