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Bilateral germ cell tumours of the testis are rare but a rise in their incidence is expected since with the new therapeutic possibilities a significant improvement in prognosis has been achieved even in patients with advanced metastatic spread. Of the 210 patients treated for malignent germ cell tumours at our Department, six (2.9%) developed a contralateral testicular tumour. All patients had metachronous tumours and the second tumours occurred after an interval ranging between 1 and 22 years. The epidemiology, histology, diagnosis, therapy and prognosis are discussed, and the significance of regular self-examination of the remaining testis in patients with testicular tumour is emphasized.  相似文献   
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Aim: Our aim was to compare the outcome in subsequent frozen embryo replacement cycles in four groups of patients who had elective cryopreservation of all their embryos because they were considered to be at increased risk of developing severe ovarian hyperstimulation syndrome. Design: Sixty-two (91%) of 68 IVF cycles (68 patients) in which elective cryopreservation of all embryos was performed were analyzed. All patients continued on the GnRH agonist, buserelin, after oocyte recovery until the onset of vaginal bleeding. Frozen embryo replacement occurred in a hormone replacement cycle that started either on day 3 of the withdrawal bleed (group I;N=15) or after serum estradiol levels had fallen to <100 pmol/L (group II;N=16). The other patients commenced a frozen embryo replacement cycle several months later in either a hormone replacement (group III;N=15) or a natural (group IV;N=16) cycle. Results: Two patients developed severe ovarian hyperstimulation syndrome. There were no significant differences among the four groups regarding demographic variables, the dose of hMG used, and the clinical outcome. There was a higher but not significantly different clinical pregnancy rate in group I (26.7%), compared to group II (12.5%), group III (13.3%), and group IV (18.8%). Conclusions: Several options exist for the timing and protocol used for frozen embryo replacement in patients who had elective cryopreservation for the prevention of ovarian hyperstimulation syndrome, none of which was found to be clearly superior in this observational report.Presented at the 1994 Annual Conference of the American Fertility Society.  相似文献   
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A methodological approach to the classification of dermoscopy images.   总被引:2,自引:0,他引:2  
In this paper a methodological approach to the classification of pigmented skin lesions in dermoscopy images is presented. First, automatic border detection is performed to separate the lesion from the background skin. Shape features are then extracted from this border. For the extraction of color and texture related features, the image is divided into various clinically significant regions using the Euclidean distance transform. This feature data is fed into an optimization framework, which ranks the features using various feature selection algorithms and determines the optimal feature subset size according to the area under the ROC curve measure obtained from support vector machine classification. The issue of class imbalance is addressed using various sampling strategies, and the classifier generalization error is estimated using Monte Carlo cross validation. Experiments on a set of 564 images yielded a specificity of 92.34% and a sensitivity of 93.33%.  相似文献   
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Microsurgical epididymal sperm aspiration (MESA) and in-vitrofertilization (IVF) were found to offer limited opportunityfor fatherhood to 45 men with obstructive azoospermia, due principallyto poor embryo implantation. Adequate sperm preparations wereobtained in 46/50 treatment cycles (92%), with the best motilityfound in the caput epididymis in 89% of cases. The mean fertilizationrate was 11.2% and fertilization occurred in 23 cycles (50%),with embryo transfer arising from 12/26 men with was aplasia(CAV), 4/9 with genital tract obstruction (EV) and 7/11 withirreversible vasectomy (VV). The overall implantation rate waslow, 8.7% per embryo transfer (11.7% per 2-3 embryo transfers)and was not improved by Fallopian transfer. There were two pregnancies(4% per cycle), both in the EV group where embryo formationand implatation (2/4, 50% per cycle) were optimum even thoughsperm preparations were paradoxically inferior to the CAV andVV groups. The spermatozoa retrieved in the two successful EVcycles were appreciably blood contaminated. Analysis of the21 failed embryo transfers showed delayed fertilization in 10cycles, cystic fibrosis (CF) mutation or familial disease in7/12 CAV men and the VV men were older (P<0.001). A pregnancywhich miscarried arose from a case of Young's syndrome, a carrierof CF mutation DF508. Male factors could thus be implicatedin the high embryo wastage of MESA cycles and might also beinfluencing implantation in other IVF procedures. Where feasible,male reconstructive surgery is preferable unless fertilizationcan be improved, possibly by speedier retrieval techniques orby permitting sperm capacitation in vitro, but probably moreeffectively by micro-assisted insemination.  相似文献   
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The study aimed to investigate the effects of dexmedetomidine against ischaemia-reperfusion injury occurring after priapism in a model of induced-priapism in rats. A total of 18 male rats were randomised into three groups. Group 1 was the control group. A priapism model was performed rats in Group 2 and then ischaemia-reperfusion injury was evaluated. Group 3 had similar procedures to the rats in Group 2. Rats in Group 3 additionally had 100 μg/kg dexmedetomidine administered intraperitoneally immediately after reperfusion. Blood and tissue samples were analysed. Biochemical analysis of blood samples revealed a decrease in the levels of the pro-inflammatory cytokines including interleukin-1 beta (IL-1 Beta), interleukin-6 (IL-6), and tumour necrosis factor-alpha (TNF-alpha) in Group 3 compared to Group 2 (p:.04, p:.009 and p:.009, respectively). Similarly, the highest malondialdehyde (MDA) level was in Group 2 (p:.002). The levels of antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities were significantly higher in Group 3 than that of Group 2 (p:.037 and p:.045, respectively). Direct microscopic examinations revealed positive changes in desquamation, oedema, inflammation and vasocongestion scores in Group 3 compared to Group 2 (p:.007, p:.008, p:.007 and p:.006, respectively). Dexmedetomidine has a protective effect against ischaemia-reperfusion injury in penile tissue.  相似文献   
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Gynaecomastia in adolescents is a benign glandular proliferation of the male breast. Secondary causes of gynaecomastia in adolescents are relatively rare and may result from a wide variety of rare pathological conditions. Among these, klinefelter syndrome, complete androgen resistance, adrenal tumours and oestrogen-secreting testicular tumours, hypogonadism, hyperthyroidism, kidney disease and medications play a role in aetiology. The aim of our study is to review the demographic characteristics, hormone profile, aetiological characteristics of paediatric gynaecomastia patients admitted to a single center and to determine the frequency of pathological gynaecomastia. Forty-three male patients with gynaecomastia who applied to the paediatric endocrinology outpatient clinic were included in our study. Demographic characteristics, physical examination findings, hormone profile, breast ultrasonography and karyotype results of the patients were recorded. There were 43 male patients in our study. Thirty-six (83.7%) of the patients were pubertal gynaecomastia, 7 (16.2%) were pathological gynaecomastia. Three of the patients with pathological gynaecomastia were prepubertal gynaecomastia, 2 had klinefelter syndrome, 1 had hypergonadotropic hypogonadism after acute lymphoblastic leukaemia treatment and 1 had gynaecomastia after spirololactone use. Careful evaluation of patients with gynaecomastia is especially important in detecting pathological types. We reported the rare prepubertal gynaecomastia and klinefelter frequency in our study.  相似文献   
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