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1.
The authors report the results of the lymphographic examinations performed on 123 patients affected with melanoma of the limbs. The patients were divided into 2 groups according to the different clinical stages; they all had pathologic confirmation. The following lymphographic parameters were considered: sensitivity, specificity, efficacy and positive/negative predictive value. The results obtained in the first group of patients (clinical stage: I) demonstrated lymphography to have low sensitivity, specificity and efficacy in the staging of melanomas (37%, 50% and 45%, respectively). On the contrary, lymphography could be trusted in the study of stage II melanomas thanks to its high sensitivity. As for stage III, the methodology had a clinical indication only in the follow-up of melanomas treated with radiochemotherapy.  相似文献   
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Lethal white foal syndrome (LWFS) is a congenital anomaly of horses characterized by a white coat colour and aganglionosis of the bowel, which is similar to Hirschsprung disease (HSCR). We decided to investigate possible mutations of the endothelin-B receptor gene ( EDNRB ) in LWFS as recent studies in mutant rodents and some patients have demonstrated EDNRB defects. First, we identified a full-length cDNA for horse EDNRB . This cDNA fragment contained a 1329 bp open reading frame which encoded 443 amino acid residues. The predicted amino acid sequence was 89, 91 and 85% identical to human, bovine and mouse as well as rat EDNRB respectively, but only 55% identical to the human, bovine and rat endothelin A receptor (EDNRA). Secondly, sequence analysis, together with allele-specific PCR and the amplification- created restriction site (ACRS) technique, revealed a dinucleotide TC-- >AG mutation, which changed isoleucine to lysine in the predicted first transmembrane domain of the EDNRB protein. This was associated with LWFS when homozygous and with the overo phenotype when heterozygous.   相似文献   
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Objective To study the relationship between human leukocyte antigen (HLA)-DRB1 and DQ alleles and the genetic susceptibility of type 1 diabetes in North Chinese children. Methods Polymerase chain reaction (PCR) techniques were used to amplify the second exon of DRB1 and DQ alleles, after which sequence specific olignucleotide probe (SSOP) dot blot hybridization techniques were used to analyze the amplified products. Results DRB1*0301, DQA1*0301, DQB1*0201 alleles and DRB1*0301-DQA1*0501-DQB1*0201 haplotype were significantly increased in patients, while DQA1*0103 and DQB1*0601 alleles were significantly increased in controls. The distribution of DR4 and DR9 haplotypes in patients and controls were not significantly different, but DR3/DR4 and DR4/DR9 heterozygotes were significantly increased in patients. Conclusions DRB1*0301, DQA1*0301 and DQB1*0201 confer susceptibility while DQA1*0103 and DQB1*0601 confer protection to type 1 diabetes. DRB1*0301-DQA1*0501-DQB1*0201 haplotype offers a predisposition to type 1 diabetes in North Chinese. Although the distribution of DR4 and DR9 in patients and controls had no significant difference, DR3/DR4 and DR3/DR9 heterozygotes were significantly increased in patients, showing that the susceptive effects of DR3 and DR4 or DR4 and DR9 haplotypes could be added up.  相似文献   
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We report our clinical experience with phototherapy in 3802 infants; 3629 were exposed to "standard" daylight phototherapy and 173 to "high-intensity" blue-light phototherapy. High-intensity blue-light phototherapy was twice as effective as standard daylight phototherapy in decreasing bilirubin concentrations. No failures occurred with high-intensity phototherapy compared with an overall failure rate of 1.84/1000 with daylight lamps; these cases were transferred to high-intensity phototherapy with prompt response. Rebound after cessation of phototherapy was greater in those exposed to high-intensity blue light with a significantly greater number requiring a second exposure. However, the incidence was still low. No third exposure was required in any infant. Nursing of infants under high-intensity blue light was more difficult and inconvenient as was clinical monitoring. The light also caused more stress on the nursing and medical personnel. However, the infants tolerated both types of phototherapy equally well. High-intensity blue-light phototherapy would seem to be the treatment of choice for infants with rapidly increasing or very high bilirubin levels, as well as in those not responding adequately to daylight phototherapy.  相似文献   
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In situ split liver transplantation for two adult recipients   总被引:9,自引:0,他引:9  
BACKGROUND: Modifications of the in situ split liver technique are needed for safe transplantation in two adult recipients with a single donor. METHODS: The graft from a brain-dead donor, 187 cm tall and weighing 89 kg, was split in situ with a transection performed along the main portal fissure retaining the middle hepatic vein with the left graft. The right and left grafts, which weighed 985 and 760 g, respectively, were transplanted in two adult recipients weighing 70 and 56 kg, respectively. RESULTS: Both recipients had minor intraoperative blood loss and were discharged from intensive care on day 3. Both grafts were rapidly functional, and the two patients were in excellent condition with normal liver function tests 9 months after surgery. CONCLUSION: In situ split liver transplantation can be performed with the middle hepatic vein retained in the left graft to obtain a sufficient volume of the two grafts suitable for two adult recipients. This modification of the technique could expand the donor pool for adult recipients.  相似文献   
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BACKGROUND: The informed consent procedure plays a central role in randomised controlled trials but has only been explored in a few studies on children. AIM: To assess the quality of the informed consent process in a paediatric setting. METHODS: A questionnaire was sent to parents who volunteered their child (230 children) for a randomised, double blind, placebo controlled trial of ibuprofen syrup to prevent recurrent febrile seizures. RESULTS: 181 (79%) parents responded. On average, 73% of parents were aware of the major study characteristics. A few had difficulty understanding the information provided. Major factors in parents granting approval were the contribution to clinical science (51%) and benefit to the child (32%). Sociodemographic status did not influence initial participation but west European origin of the father was associated with willingness to participate in future trials. 89% of participants felt positive about the informed consent procedure; however, 25% stated that they felt obliged to participate. Although their reasons for granting approval and their evaluation of the informed consent procedure did not differ, relatively more were hesitant about participating in future. Parents appreciated the investigator being on call 24 hours a day (38%) and the extra medical care and information provided (37%) as advantages of participation. Disadvantages were mainly the time consuming aspects and the work involved (23%). CONCLUSIONS: Parents' understanding of trial characteristics might be improved by designing less difficult informed consent forms and by the investigator giving extra attention and information to non-west European parents. Adequate measures should be taken to avoid parents feeling obliged to participate, rather than giving true informed consent.  相似文献   
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Bagby  GC Jr; McCall  E; Bergstrom  KA; Burger  D 《Blood》1983,62(3):663-668
Human umbilical vein endothelial cells were cultured in supernatants of peripheral blood monocytes that had been cultured for 3 days with and without lactoferrin. Colony-stimulating activity (CSA) was measured in supernatants of the endothelial cell cultures and appropriate control cultures using normal, T-lymphocyte-depleted, phagocyte-depleted, low- density bone marrow cells in colony growth (CFU-GM) assays. Monocyte- conditioned medium contained a nondialyzable, heat labile factor that enhanced 4-15--fold the production of CSA by endothelial cells. The addition of lactoferrin to monocyte cultures reduced the activity of this monokine by 69%. Lactoferrin did not inhibit CSA production by monokine-stimulated endothelial cells. Therefore, vascular endothelial cells are potent sources of CSA, the production of CSA by these cells is regulated by a stimulatory monokine, and the production and/or release of the monokine is inhibited by lactoferrin, a neutrophil- derived putative feedback inhibitor of granulopoiesis. Inasmuch as a similar monokine is known to stimulate CSA production by fibroblasts and T lymphocytes, we suggest that mononuclear phagocytes play a pivotal role in the regulation of granulopoiesis by recruiting a variety of cell types to produce CSA.  相似文献   
10.
As one in a series reporting on DAIGE (Drug Agencies Information Gathering Exercise), this paper looks at funding and organizational management within voluntary drug agencies in London. The paper provides the opportunity for agencies to look at issues, vital to their survival, while offering future directions, focused on financial support and accountability. This discussion calls for active management and coordinated action regarding funding in the development of an overall strategy for voluntary drug agencies. It also highlights the need for funders, managers, and workers to assess together priorities for survival.  相似文献   
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