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1.
Interferon-alpha (IFN-alpha) has proved effective in the treatment of hemangiomas, hemangioblastomas, and Kaposi's sarcoma. To investigate the ability of IFNs to inhibit angiosarcoma, we used two transformed murine endothelial cell lines that form angiosarcomas in vivo. SVR and MS1-VEGF cell lines express oncogenic H-ras or vascular endothelial growth factor (VEGF), respectively. IFN-alpha1,8, which is active against murine and human cells, inhibited SVR and MS1-VEGF proliferation in vitro by 40% at 10(3) U/mL (p = 0.028). In vivo, IFN-alpha1,8 inhibited SVR tumor volume by 71% (p = 0.047) and MS1-VEGF volume by 79% (p = 0.003). Tumor-induced angiogenesis was decreased in SVR tumors by 52% (p = 0.005) and in MS1-VEGF tumors by 58% (p = 0.001). Sera from IFN-alpha1,8-treated mice bearing either SVR or MS1-VEGF tumors demonstrated a 5-fold increase in IP-10/CXCL10 (p = 0.001), an IFN-induced antiangiogenic protein. Both recombinant IP-10 and IFN-alpha1,8 inhibited human umbilical vein endothelial cell (HUVEC) vessel formation in the fibrin gel assay, a three-dimensional culture model of angiogenesis, by 56% at 25 ng/mL and 50% at 1.2 ng/mL, respectively (p < 0.001). An IP-10 blocking antibody restored vessel formation to 80% of untreated controls (p = 0.001). Given the magnitude of the in vivo response, these data suggested that the antitumor effects of IFN-alpha1,8 were likely mediated through angiogenesis inhibition rather than solely by direct inhibition of tumor cell proliferation.  相似文献   
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Salivary disease in childhood is uncommon. Clinical features are much the same as in adult disease, however, congenital, inflammation, and functional disease is more common. Management is governed by the same general principles in all age groups. Congenital abnormalities are rare. Inflammation, either bacterial or viral, is the most common disease. Chronic sialadenitis usually resolves at puberty. Neoplasia is rare, and the majority of tumors are benign and occur in the parotid gland. Malignancy is suggested by rapid growth, pain, skin fixation, and lymphadenopathy. Surgical treatment of sialorrhea should only be considered after careful assessment. Relocation of the submandibular ducts is the treatment of choice.  相似文献   
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The cases of 46 children who had been abused sexually an average of 2.6 years previously, were reviewed and the non-offending parents were interviewed with emphasis on how they viewed the professional persons who had seen their children, and their opinions of the legal processes that were instituted. The parents found most professional groups helpful, with officers from the Department of Youth and Community Services being seen as the least helpful. Twenty-one of the cases went to court; in 12 cases this resulted in a conviction, and prison sentences were imposed on six of the offenders. Children found the court experience distressing and most parents expressed dissatisfaction with the outcome of the court hearing. Children were more likely to be required to give evidence in court if the offender had legal representation. Persisting behavioural problems and poor school performance were more likely to occur in those cases in which there had been court hearings. A review of Police Department records of children who had attended the hospital for the management of sexual assault, showed that 10 of the 107 children who are now aged over 14 years, have themselves been convicted of violent crimes since their episode of sexual assault. Long-term intervention is required to help many of these children, some legal reforms are necessary to reduce the stress that they experience when there is a court hearing, and all the professional groups that are likely to become involved with the problem of the sexual abuse of children need to be better informed about its seriousness and consequences.  相似文献   
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The aim of the study was to determine whether a prior diagnostic testicle biopsy can predict success or failure of testicular sperm extraction (TESE) with intracytoplasmic sperm injection (ICSI) in patients with non-obstructive azoospermia caused by testicular failure, and what is the minimum threshold of sperm production in the testis which must be surpassed for spermatozoa to reach the ejaculate. Forty- five patients with non-obstructive azoospermia caused by testicular failure underwent diagnostic testicle biopsy prior to a planned future TESE-ICSI procedure. The diagnostic testicle biopsy was analysed quantitatively, and correlated with the quantitative findings of spermatogenesis in patients with normal spermatogenesis, as well as with the results of subsequent attempts at TESE-ICSI. Men with non- obstructive azoospermia caused by germinal failure had a mean of 0-6 mature spermatids/seminiferous tubule seen on a diagnostic testicle biopsy, compared to 17-35 mature spermatids/tubule in men with normal spermatogenesis and obstructive azoospermia. These findings were the same for all types of testicular failure whether Sertoli cell only, maturation arrest, cryptorchidism, or post-chemotherapy azoospermia. Twenty-two of 26 men with mature spermatids found in the prior testis biopsy had successful retrieval of spermatozoa for ICSI, 12 of their partners became pregnant, and are either ongoing or delivered. The study suggests that 4-6 mature spermatids/tubule must be present in the testis biopsy for any spermatozoa to reach the ejaculate. More than half of azoospermic patients with germinal failure have minute foci of spermatogenesis which are insufficient to produce spermatozoa in the ejaculate. Prior diagnostic testicle biopsy analysed quantitatively (for the presence of mature spermatids) can predict subsequent success or failure with TESE-ICSI. Incomplete testicular failure may involve a sparse multi-focal distribution of spermatogenesis throughout the entire testicle, rather than a regional distribution. Therefore, it is possible that massive testicular sampling from many different regions of the testes may not be necessary for successful TESE-ICSI.   相似文献   
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Teaching children about skin cancer prevention: why wait for adolescence?   总被引:1,自引:0,他引:1  
Abstract: The baseline knowledge about skin cancer prevention of 983 children aged 8 to 12 years was assessed by a pretest questionnaire. After the pretest, half were given a formal presentation about skin cancer prevention. The other half participated in an informal, question–and–answer session, which covered all material from the formal presentation. Two weeks later, all students completed an identical post–test. The students had a high baseline level of knowledge about skin cancer prevention. Knowledge increased for most items in the post–test questionnaire. In all age groups there was no difference in results between the formal and interactive teaching sessions, except among eight–year–olds, for whom the formal presentation was more effective. As much solar skin damage occurs before adolescence, the younger age group is the important target for skin cancer prevention programs. (Aust N Z J Public Health 1997; 21: 602–5)  相似文献   
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β-Lactoglobulin was isolated from infant formulae that were ultra high temperature (UHT) -treated, sterilized or spray-dried. The effect of the isolated β-lactoglobulin on SfaII-fimbriae-mediated adhesion of Escherichia coli to human ileostomy glycoproteins was studied in vitro. β-Lactoglobulin isolated from sterilized formulae was found to perform significantly less well than preparations from spray-dried formulae (p = 0:05). Great heterogeneity was observed in the adhesion inhibitory capacity of β-lactoglobulin isolated from UHT-treated formulae. Therefore, no significant difference was observed between UHT-treated and sterilized formulae or spray-dried formulae (p < 0:10). It can be hypothesized that β-lactoglobulin from spray-dried and some UHT-treated infant formulae may affect the colonization of mucous membranes by E. coli strains causing neonatal septicaemia and meningitis.  相似文献   
10.
Three hundred and forty-two health professionals who deal with children, including general practitioners, paediatric residents and paediatric nurses were asked questions about their knowledge of infant feeding, particularly how they would recommend mothers to reconstitute milk formulae. A proportion of errors was noted in all groups, with errors occurring more frequently in the medical groups. Mothers seeking feeding advice are most likely to obtain the correct answers from paediatrically trained nurses.  相似文献   
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