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1.
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   
2.
BACKGROUND: Relatively few studies have been conducted linking decreasing intraocular pressure (IOP) to preservation of visual field. This investigation was conducted to determine if this link could be made and to compare the long-term effect of two ocular hypotensive agents on preservation of visual field. METHODS: In an observer-masked study, 189 patients with primary open-angle glaucoma received either timolol or pilocarpine by random allocation. The dose of antiglaucoma agent was increased from 0.25% to 0.5% twice daily for timolol or from 2% to 4% four times daily for pilocarpine if the initial IOP response was inadequate. After an on-treatment baseline, visual fields were followed every 4 months for 2 years using the Octopus program 32. RESULTS: Compared with timolol, significantly more patients receiving pilocarpine discontinued use because of inadequate IOP control (P < or = 0.01). By comparing the mean visual field scores, it can be seen that the pilocarpine group had a significantly worse score at all timepoints from month 4 to month 24. The pilocarpine group also had a greater mean number of test loci with decreased sensitivity of 5 or more decibels (dB) at all timepoints. The mean within-patient regression slope for timolol was 0.01 dB/month and for pilocarpine was -0.06 dB/month (P < 0.01). The study has shown that over a 2-year period, patients treated with pilocarpine 2% or 4% four times daily experienced a significantly greater visual field deterioration than that seen in patients receiving either 0.25% or 0.5% timolol twice daily. CONCLUSION: Although these data do not support a link between lowering of IOP and visual field preservation, treatment with timolol was associated with significantly less visual field loss than treatment with pilocarpine.  相似文献   
3.
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   
7.
FANCG was the third Faconi anaemia gene identified and proved to be identical to the previously cloned XRCC9 gene. We present the pathogenic mutations and sequence variants we have so far identified in a panel of FA-G patients. Mutation screening was performed by PCR, single strand conformational polymorphism analysis and protein truncation tests. Altogether 18 mutations have been determined in 20 families - 97% of all expected mutant alleles. All mutation types have been found, with the exception of large deletions, the large majority is predicted to lead to shortened proteins. One stop codon mutation, E105X, has been found in several German patients and this founder mutation accounts for 44% of the mutant FANCG alleles in German FA-G patients. Comparison of clinical phenotypes shows that patients homozygous for this mutation have an earlier onset of the haematological disorder than most other FA-G patients. The mouse Fancg sequence was established in order to evaluate missense mutations. A putative missense mutation, L71P, in a possible leucine zipper motif may affect FANCG binding of FANCA and seems to be associated with a milder clinical phenotype.  相似文献   
8.
The production of cytokines by atheromatous plaque macrophages from human endarterectomy tissue was assessed in vitro by short-term cell culture and in situ by immunohistology. Macrophages were isolated from plaques of 14 patients undergoing carotid endarterectomy and 7 patients undergoing reconstructive procedures on atheromatous distal aortic and femoral arteries. Tumor necrosis factor (TNF) and interleukin 1 (IL-1) production by plaque macrophages and blood monocytes isolated concurrently from these patients was assessed. TNF release by macrophages from carotid plaques (0.39 +/- 0.12 ng/10(6) cells/24 hours) was significantly augmented compared to the release by corresponding blood monocytes (0.014 +/- 0.011 ng/10(6) cells/24 hours, P = 0.03), and by macrophages from noncarotid lesions (0.038 +/- 0.036 ng/10(6) cells/24 hours, P < 0.04). Cellular TNF expression by macrophages within carotid plaques was also more prominent than in noncarotid lesions. By contrast, IL-1 production by plaque macrophages from both carotid and noncarotid plaques was not augmented compared to blood monocytes, and only infrequent and low-intensity labeling for IL-1 was present on macrophages within plaques from either group. These results provide functional and immunohistological evidence for increased production of TNF but not IL-1 by activated macrophages, indicating local and selective augmentation of cytokine production within carotid plaques. This suggests that macrophages play an active role in the inflammatory response within atheromatous carotid plaques.  相似文献   
9.
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   
10.
Conflicting reports exist regarding the effects of interleukin-10 (IL-10) on mesangial cells. There have been reports of both proliferative and antiproliferative effects, and both proinflammatory and anti-inflammatory effects of IL-10 on mesangial cells. However, the potential for IL-10 to affect glomerulonephritis characterized by mesangial proliferation is not known. To test the hypothesis that IL-10 would limit experimental mesangial proliferative glomerulonephritis, IL-10 was administered to rats in which mesangial proliferative glomerulonephritis was induced by administration of anti-Thy 1 antibody. Compared to control treated rats, IL-10 treated rats showed less proliferation, with fewer cells in glomeruli. Glomerular cellular proliferation was reduced, assessed by the numbers of cells within glomeruli expressing either proliferating cell nuclear antigen (PCNA) or bromodeoxyuridine. Glomerular macrophage influx (but not the proportion of glomerular macrophages that were PCNA positive) was reduced by IL-10 administration. There was no significant reduction in glomerular alpha-smooth muscle actin staining. IL-10 treatment resulted in reduced renal IL-1beta mRNA expression and reduced glomerular ICAM-1 expression, but renal expression of MCP-1 and osteopontin mRNA was unaltered. This study demonstrates that in experimental mesangial proliferative glomerulonephritis IL-10 diminishes inflammatory cell recruitment and mesangial cell proliferation. The effects of IL-10 in inhibiting mesangial cell proliferation are likely to be due to a combination of direct effects of IL-10 on mesangial cells and effects mediated by macrophages.  相似文献   
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