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981.
We report here two cases which illustrate the magnetic resonance imaging (MRI) appearance of the Mirena levonorgestrel releasing intra-uterine system and the GyneFix copper intra-uterine contraceptive implant. The MRI appearance of these devices has not to our knowledge been reported to date, and as increasing numbers of women choose to use these devices for treatment of gynaecological conditions and contraception, it becomes increasingly important to recognise their appearance on pelvic imaging. 相似文献
982.
The increase in communication skills training for doctors has led to the need for more effective means of evaluation. Analysis of video and audiotaped consultations using systems of interaction analysis can provide the trainee with in-depth feedback about their communication skills. Most interaction process systems were designed for use in primary care and recent research has questioned the applicability of these systems in medical specialties such as oncology. We describe the development of a new instrument, the Medical Interaction Process System (MIPS) for use in teaching communication skills and empirical research in medical encounters, particularly, between doctors and patients with cancer. A comparison of the MIPS and comparable behaviour categories of another widely used system (the Roter Interaction Analysis System) was made to test convergent validity. Pearson correlation coefficients suggested a good level of concurrence between the two systems. Intercoder reliability tests were carried out between two coders at two separate time periods. Both of these indicated good reliability for the majority of categories. The two major advantages of the MIPS over other coding systems are: (1) the system allows for sequential and parallel coding, thus avoiding major coding conflicts and (2) the design of the coding sheet results in a multidimensional view of the consultation without data loss. We believe that the MIPS yields useful information for teaching doctors communication skills and also provides an objective method for evaluating the effectiveness of communication skills courses. 相似文献
983.
Feeding problems in young PKU children 总被引:3,自引:0,他引:3
A MacDonald GW Rylance DA Asplin K Hall G Harris IW Booth 《Acta paediatrica (Oslo, Norway : 1992)》1994,83(S407):73-74
Behavioural feeding problems were found to be more prevalent in a group of 15 PKU children aged 1-5 years when compared to non-PKU controls. The parents of PKU children identified poorer appetites ( p < 0.01), a more limited range of foods consumed ( p < 0.03) and more gastrointestinal symptoms such as vomiting and constipation ( p < 0.03) than control children. The children were slower to feed ( p < 0.03), were more likely to dislike sweet foods and some ate separately from the rest of the family at mealtime ( p < 0.03). The effects on normal feeding behaviour should be considered when advocating strict diet therapy for young PKU children. 相似文献
984.
Doolittle ND Miner ME Hall WA Siegal T Jerome E Osztie E McAllister LD Bubalo JS Kraemer DF Fortin D Nixon R Muldoon LL Neuwelt EA 《Cancer》2000,88(3):637-647
BACKGROUND: The aim of this study was to determine the safety and efficacy of intraarterial chemotherapy with osmotic opening of the blood-brain barrier (BBB) for the treatment of malignant brain tumors when administered across multiple centers. METHODS: Patients with primary central nervous system lymphoma (PCNSL), primitive neuroectodermal tumor (PNET), germ cell tumor, cancer metastasis to the brain, or low or high grade glioma were eligible. Prior to entry, magnetic resonance imaging or computed tomography brain scan, medical history, neurologic status, and Karnofsky performance status were reviewed at the coordinating center. Standardized anesthesia and intraarterial catheterization guidelines were followed by a multidisciplinary team at each center. Between March 1994 and November 1997, 5 universities treated 221 adult patients with intraarterial chemotherapy with or without osmotic opening of the BBB (2464 procedures). RESULTS: Of evaluable patients with PCNSL, 40 of 53 (75%) achieved complete response (CR). All evaluable patients with PNET (n = 17), metastatic disease (n = 12), or germ cell tumor (n = 4) achieved stable disease (SD) or better. Of 57 evaluable patients with glioblastoma multiforme, 45 (79%) achieved SD or better. Asymptomatic subintimal tear occurred in 11 of 221 patients (5%), pulmonary embolism in 6 of 221 (2.7%), and renal toxicity in 4 of 221 (1.8%). One patient with extensive glioma expired within 48 hours after treatment. CONCLUSIONS: Using standard guidelines and protocols, intraarterial chemotherapy with or without osmotic opening of the BBB is feasible across multiple centers with a low incidence of catheter-related complications. In patients with chemotherapy-sensitive tumors, such as PCNSL, PNET, germ cell tumor, and cancer metastasis to the central nervous system, enhanced delivery results in a high degree of tumor response, with an efficacy profile that is reproducible across multiple centers. 相似文献
985.
Dendritic cells break tolerance and induce protective immunity against a melanocyte differentiation antigen in an autologous melanoma model 总被引:15,自引:0,他引:15
Schreurs MW Eggert AA de Boer AJ Vissers JL van Hall T Offringa R Figdor CG Adema GJ 《Cancer research》2000,60(24):6995-7001
Tyrosinase-related protein (TRP) 2 belongs to the melanocyte differentiation antigens and has been implicated as a target for immunotherapy of human as well as murine melanoma. In the current report, we explored the efficacy of nonmutated epitopes with differential binding affinity for MHC class I, derived from mouse TRP2 to induce CTL-mediated, tumor-reactive immunity in vivo within the established B16 melanoma model of C57BL/6 mice. The use of nonmutated TRP2-derived epitopes for vaccination provides a mouse model that closely mimics human melanoma without introduction of xenogeneic or otherwise foreign antigen. The results demonstrate that vaccination with TRP2 peptide-loaded bone marrow-derived dendritic cells (DCs) results in activation of high avidity TRP2-specific CTLs, displaying lytic activity against both B16 melanoma cells and normal melanocytes in vitro. In vivo, protective antitumor immunity against a lethal s.c. B16 challenge was observed upon DC-based vaccination in this fully autologous tumor model. The level of protective immunity positively correlated with the MHC class I binding capacity of the peptides used for vaccination. In contrast, within this autologous model, vaccination with TRP2 peptide in Freund's adjuvant or TRP2-encoding plasmid DNA did not result in protective immunity against B16. Strikingly, despite the observed CTL-mediated melanocyte destruction in vitro, melanocyte destruction in vivo was sporadic and primarily restricted to minor depigmentation of the vaccination site. These results emphasize the potency of DC-based vaccines to induce immunity against autologous tumor-associated antigen and indicate that CTL-mediated antitumor immunity can proceed without development of adverse autoimmunity against normal tissue. 相似文献
986.
Hall IH Lackey CB Kistler TD Ives JS Beraldo H Ackerman LJ West DX 《Archiv der Pharmazie》2000,333(7):217-225
A number of thiosemicarbazones have been tested previously and herein are included three bis(thiosemicarbazones) for comparison to the previous derivatives. In general the uncomplexed thiosemicarbazones were more potent in the cytotoxic screens than the bis(thiosemicarbazone) except in the murine L1210 and the human colon SW480 screens. Mode of action studies have only demonstrated slight differences in the effects of the two types of compounds on nucleic acid metabolism. The symmetrical and unsymmetrical bis(thiosemicarbazones) complexes of copper, nickel, zinc, and cadmium have been examined to compare them to the heterocyclic N(4)-substituted thiosemicarbazones metal complexes. These new derivatives demonstrated excellent activity against the growth of suspended lymphomas and leukemias although it should be pointed out that generally they were not as active as the copper complexes of N(4)-substituted thiosemicarbazones. Nevertheless, selected bis(thiosemicarbazones) complexes were active against the growth of human lung MB9812, KB nasopharynx, epidermoid A431, glioma UM-86, colon SW480, ovary 1-A9, breast MCK-7, and osteosarcoma Saos-2. In human HL-60 promyelocytic leukemia cells the complexes preferentially inhibited DNA and purine syntheses over 60 min. The regulatory enzyme of the de novo purine pathway, IMP dehydrogenase, appeared to be a major target of the complexes. However, minor inhibition of the activities of DNA polymerase alpha, PRPP-amido transferase, ribonucleotide reductase, and nucleoside kinases occurred over the same time period. No doubt these effects of the complexes on nucleic acid metabolism were additive since the d[NTP] pool levels were reduced after 60 min as was DNA synthesis. The symmetrical and unsymmetrical bis(thiosemicarbazones) and their metal complexes did not cause as severe DNA fragmentation as the heterocyclic N(4)-substituted thiosemicarbazone metal complexes; furthermore, their metabolic effects in the tumor cell were more focused on a single synthetic pathway. 相似文献
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