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BACKGROUND: Development of more than one primary melanoma in a patient is a relatively uncommon but well-recognized phenomenon. Its frequency has ranged from 1.2% to 8.2% in several series. This subgroup of patients with multiple primary lesions has not been characterized sufficiently. We report the experience of the Melanoma Unit of University Hospital Spedali Civili of Brescia, Italy. METHOD: Study subjects were drawn from 1240 patients with histologically confirmed melanoma, including melanoma in situ. From this group, multiple melanomas developed in 47 patients (3.79%). Every one of our patients has been taught to perform self-examination of the skin to detect suspicious pigmented lesions. RESULTS: Of the 47 patients described in this study, 38 had two primary melanomas, 7 had three melanomas and 2 had 5 and 10 melanomas, respectively. Mean age at first diagnosis was 46.2 years. The majority of subsequent melanomas (74.5%) were removed within 5 years of the initial operation. Synchronous lesions were found in 10 patients. In male patients, the lesion appeared most frequently on the trunk; in female patients, melanoma appeared mostly on the lower extremities. The second primary melanomas developed in the same anatomic region from the first in 53.2% of our patients. The proportion of in situ to invasive melanomas was greater for the second melanomas compared with the first melanomas. Regarding invasive melanomas, the mean thickness of the first melanomas was 1.31 mm compared with 0.66 mm for the second ones. Dividing patients into two groups, of more and less than 50, it is highlighted that in older patients synchronous lesions appear more frequently (36.4% vs. 8.0%); the median time interval between sequential melanomas is longer (84 vs. 63.7 months); and the ratio between the primary and secondary melanoma mean thickness is lower (1.21 : 1.08 vs. 1.43 : 0.63 mm). CONCLUSIONS: The study confirms that second primary melanoma is usually thinner than the first lesion, and it is more common in the same region of the body as the initial melanoma. The highest risk for a second melanoma is during the first 5 years, but a much longer time interval of 28 years is possible. Continued medical follow-up with complete skin examinations seems prudent, but it is very important to promote self-skin evaluation in patients to detect not only metastases but also subsequent primary melanomas in their earliest phases.  相似文献   
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We report an instance of critical ovarian hyperstimulation syndrome in a highly responsive in-vitro fertilization patient despite the preventive measure of a 4 day 'coast' interval during which no gonadotrophins were administered while gonadotrophin-releasing hormone agonist therapy continued until serum oestradiol concentrations fell below 3000 pg/ml.   相似文献   
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The objective of this study was to evaluate the Doppler flow variations which occur following the use of different protocols of ovarian stimulation in an IVF programme, and to investigate the thromboxane production by cultured endometrial cells and its influence on embryo implantation. A total of 60 patients underwent three different ovarian stimulation protocols: long gonadotrophin-releasing hormone agonist (GnRH-a), short GnRH-a and no GnRH-a. Transvaginal ultrasonography and colour Doppler analysis were performed before and during the treatment. On the day that the Doppler examination took place, luteinizing hormone, follicle stimulating hormone, plasma oestradiol and thromboxane concentrations were assayed. On the day of oocyte retrieval, endometrial cells were collected and cultured, and their thromboxane production evaluated. No significant differences in hormonal, ultrasonographic or Doppler parameters were observed between the three groups. Ten out of 56 patients who had a successful embryo transfer became pregnant. In the group of pregnant women the pulsatility index values of both uterine and spiral arteries was lower than in non-pregnant patients, and was associated with significantly lower thromboxane concentrations from cultured endometrial cells. It is concluded that thromboxane plays a role in embryo implantation, and that Doppler flow analysis of uterine and spiral arteries in infertile patients may be important in the management of ovarian stimulation.   相似文献   
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The life table attributes of Culex tarsalis Coquillett females infected experimentally by feeding on 4 and 6 log10 plaque-forming units (PFU) of western equine encephalomyelitis virus (WEEV) per milliliter of heparinized chicken blood were compared with an uninfected control group. Females continually were offered 10% sucrose and an oviposition substrate and daily a blood meal through a biomembrane feeder. Mortality (dead females) and fecundity (female eggs per female) were monitored daily until all females died. Overall, 94% of 198 females in the two virus-infected groups were positive for WEEV at death when tested by plaque assay; the average body virus titer at death did not differ between groups. WEEV infection significantly altered the life table characteristics of Cx. tarsalis. Life expectancy at infection in days (ex), reproductive effort in female eggs per female per generation (Ro), and generation time (T) in days for the infected cohorts were significantly lower than for the uninfected controls, whereas the reproductive rate (rc) in female eggs per female per day was higher for infected than uninfected cohorts. In agreement with the WEEV infection data that showed similar body titers, there were few differences between the life table parameters for the 4 and 6 log10 PFU treatment groups. Greatest differences were observed for survivorship between days 17-40 when virus titers in infected dying females were greatest. Our data extend recent studies that indicate mosquito infection with encephalitis viruses has a cost of reduced life expectancy and fitness.  相似文献   
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The introduction of a St. Louis encephalitis virus (SLE) genotype new to southeastern California during 2000 was followed by focal enzootic amplification in the Coachella Valley that was detected by seroconversions of 29 sentinel chickens in five of nine flocks of 10 chickens each, isolations of virus from 30 of 538 pools of 50 Culex tarsalis Coquillett females, and collection of 30 positive sera from 2,205 wild birds. This SLE strain over wintered successfully and then amplified during the summer of 2001, with 47 sentinel seroconversions in eight of nine flocks, 70 virus isolations from 719 pools of Cx. tarsalis and Cx. p. quinquefasciatus Say, and 40 positive sera from 847 wild birds. Human illness was not detected by passive case surveillance, despite issuance of a health alert during 2001. Virus amplification during both years was associated with above average temperatures conducive for extrinsic incubation and below average precipitation during spring associated with below average vector abundance. Seroconversions by sentinel chickens provided the timely detection of virus activity, with initial conversions detected before positive mosquito pools or wild bird infections. Vertical infection was not detected among Cx. tarsalis adults reared from immatures collected during the fall-winter of 2000, even though SLE over wintered successfully in this area. Early seroconversions by a sentinel chicken during February 2001 and a recaptured Gambel's quail in April 2001 provided evidence for transmission during winter and spring when ambient temperatures averaged below 17 degrees C, the threshold for SLE replication.  相似文献   
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Maternal serum concentrations of inhibin-A, inhibin-B, activin-A, activin-AB, pro-alphaC-related inhibin forms, total follistatin, steroids and gonadotrophins were measured longitudinally in six normal singleton pregnancies. Maternal venous blood was collected randomly during a spontaneous follicular phase prior to donor insemination, at 5, 7, 9, 11, 16, 20, 24, 28, 32 and 36 weeks after the first missed menses and in the early puerperium. Steroid and gonadotrophin profiles conformed to previous reports. While at week 5 of gestation inhibin-A, activin-A and follistatin concentrations were similar to those at the follicular phase, all three increased progressively (P < 0.001) to maximal concentrations in week 36: approximately 48-fold (3740 +/- 1349 ng inhibin-A/ml), approximately 22-fold (6109 +/- 1443 ng activin-A/ml) and approximately 10-fold (3563 +/- 418 ng follistatin/ml) higher. Pro- alphaC concentrations reached a maximum in weeks 5 (approximately 5- fold, P < 0.001) and 36 (1027 +/- 174 pg/ml, P < 0.01). Inhibin-B (71 +/- 23 pg/ml prior to pregnancy) was undetectable (<12 pg/ml) between week 5-16 of gestation but increased slightly in the third trimester (26 +/- 7 pg/ml in week 36). Activin-AB was undetectable throughout pregnancy. Post-partum concentrations of inhibin-A (41 +/- 12 ng/ml), inhibin-B (<12 pg/ml), activin-A (950 +/- 149 pg/ml), pro-alphaC (128 +/- 22 pg/ml) and follistatin (990 +/- 79 ng/ml) were substantially lower than at week 36 of gestation. The activin-A:follistatin ratio increased from 0.5 in week 5 to 1.8 in week 36, suggesting that more free activin-A is available in the maternal circulation during late pregnancy.   相似文献   
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