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61.
62.
胃癌组织中MVD和VEGF表达与影像学表现的关系   总被引:2,自引:2,他引:2  
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63.
Summary Forthy-three patients with ovarian carcinoma were treated with whole-abdomen radiation (moving strip±pelvic radiation), 15 patients had not received prior chemotherapy, and 28 patients were irradiated following chemotherapy and second-look laparotomy. Ten of these had been treated with a variety of chemotherapy regimens (L-PAM, CHAD, Hexa-CAF). Eighteen patients were treated in an ongoing prospective trial with combination chemotherapy consisting of melphalan, cis-platinum, and hexamethylmelamin (HexaPAMP). Thrombocytopenia was the limiting toxicity. A temporary pause in the radiation schedule allowing platelets to recover made it possible to complete treatment in 80% of the patients. The acute toxic effects, which included the expected side effects of radiation therapy on intestine, liver and lung, were not more frequent or more severe in the patients who had received prior chemotherapy than in those who had radiation therapy alone. Thirty-four of 43 patients (stage I, seven patients; stage II, seven patients; stage III, 27 patients; stage IV, two patients) are alive and without evidence of disease 26+ months (range 7 to 64 months) after entering the postsurgical treatment program.Paper presented at the Annual Meeting of the Swiss Society for Oncology, Basel, March 1983  相似文献   
64.
Mucinous carcinomas represent a distinct morphological subtype which can arise from several organ sites, including the ovary, and their genetic characteristics are largely under‐described. Exome sequencing of 12 primary mucinous ovarian tumours identified RNF43 as the most frequently somatically mutated novel gene, secondary to KRAS and mutated at a frequency equal to that of TP53 and BRAF. Further screening of RNF43 in a larger cohort of ovarian tumours identified additional mutations, with a total frequency of 2/22 (9%) in mucinous ovarian borderline tumours and 6/29 (21%) in mucinous ovarian carcinomas. Seven mutations were predicted to truncate the protein and one missense mutation was predicted to be deleterious by in silico analysis. Six tumours had allelic imbalance at the RNF43 locus, with loss of the wild‐type allele. The mutation spectrum strongly suggests that RNF43 is an important tumour suppressor gene in mucinous ovarian tumours, similar to its reported role in mucinous pancreatic precancerous cysts. Copyright © 2012 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
65.
Type 1 diabetes (T1D) is characterized by the destruction of the insulin-producing β-cells of pancreatic islets. Genetic and environmental factors both contribute to T1D development. Viral infection with enteroviruses is a suspected trigger for T1D, but a causal role remains unproven and controversial. Studies in animals are problematic because of species-specific differences in host cell susceptibility and immune responses to candidate viral pathogens such as coxsackievirus B (CVB). In order to resolve the controversial role of viruses in human T1D, we developed a viral infection model in immunodeficient mice bearing human islet grafts. Hyperglycemia was induced in mice by specific ablation of native β-cells. Human islets, which are naturally susceptible to CVB infection, were transplanted to restore normoglycemia. Transplanted mice were infected with CVB4 and monitored for hyperglycemia. Forty-seven percent of CVB4-infected mice developed hyperglycemia. Human islet grafts from infected mice contained viral RNA, expressed viral protein, and had reduced insulin levels compared with grafts from uninfected mice. Human-specific gene expression profiles in grafts from infected mice revealed the induction of multiple interferon-stimulated genes. Thus, human islets can become severely dysfunctional with diminished insulin production after CVB infection of β-cells, resulting in diabetes.  相似文献   
66.
IntroductionAcute appendicitis in the developing world has a markedly different disease profile to that in the developed world.MethodsA retrospective study was undertaken over a four-year period at a university hospital in South Africa to review the disease spectrum and the clinical outcome of acute appendicitis.ResultsA total of 1,004 patients (54% male, median age: 18 years) with intraoperatively confirmed appendicitis were reviewed. Over half (56%) were from the urban district within the city of Pietermaritzburg and the remaining 44% were from the rural health district. The median duration of illness from onset to definitive care was 4 days. Sixty per cent of appendices were perforated and associated with intra-abdominal contamination. Forty per cent of patients required reoperation to control intra-abdominal sepsis. Ten per cent required admission to the intensive care unit. The median overall length of hospital stay was 5 days. The mortality rate was 1%.Rural patients had a longer median duration of illness (3 vs 5 days, p<0.001) as well as a more advanced disease profile associated with perforation and severe intra-abdominal sepsis (19% vs 71%, p<0.001). Female patients had a longer median duration of illness (3 vs 4 days, p<0.001), were more likely to present with severe intra-abdominal sepsis (31% vs 54%, p<0.001) and were more likely to require a laparotomy (50% vs 73%, p<0.001). The total cost of managing the entire cohort of 1,004 patients over the 4-year period was £2,060,972.ConclusionsAcute appendicitis in South Africa is a serious disease associated with significant morbidity. Late presentation is common. Female and rural patients have the worst clinical outcomes, with significant cost to the health system.  相似文献   
67.
Siefer  AK; Longo  DL; Harrison  CL; Reynolds  CW; Murphy  WJ 《Blood》1993,82(8):2577-2584
Purified populations of natural killer (NK) cells were obtained from mice with severe combined immune deficiency (SCID). SCID spleen cells were cultured and activated with recombinant human interleukin-2 (rhIL- 2) in vitro. The activated NK cells were then transferred with syngeneic BALB/c bone marrow cells (BMC) and rhIL-2 into lethally irradiated syngeneic recipients to determine their effect on long-term hematopoietic reconstitution. On analysis, the transfer of rhIL-2- activated NK cells along with BMC resulted in significant increases in splenic and BM hematopoietic progenitor cells when compared with those for mice not receiving NK cells. Histologic and flow cytometric analysis showed a marked increase in granulocytic and megakaryocytic lineage cells present in the spleens of the mice receiving activated NK cells. Analysis of the peripheral blood indicated that the transfer of activated NK cells with BMC also significantly improved platelet and total white blood cell counts, with increases in segmented neutrophils. Erythroid recovery was not affected. Finally, lethally irradiated mice receiving activated NK cells and rhIL-2 along with limiting numbers of syngeneic BMC showed a marked increase in survival rate. These results show that the use of populations enriched for activated NK cells after syngeneic BM transplantation (BMT) has a profound enhancing effect on engraftment primarily affecting megakaryocytic and granulocytic cell reconstitution. Therefore, the transfer of activated NK cells and rhIL- 2 may be of clinical use to promote hematopoietic reconstitution after BMT.  相似文献   
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69.
Immunodeficient mice engrafted with human HSCs support multidisciplinary translational experimentation, including the study of human hematopoiesis. Heightened levels of human HSC engraftment are observed in immunodeficient mice expressing mutations in the IL2-receptor common γ chain (IL2rg) gene, including NOD-scid IL2rγ(null) (NSG) mice. Engraftment of human HSC requires preconditioning of immunodeficient recipients, usually with irradiation. Such preconditioning increases the expression of stem cell factor (SCF), which is critical for HSC engraftment, proliferation, and survival. We hypothesized that transgenic expression of human membrane-bound stem cell factor Tg(hu-mSCF)] would increase levels of human HSC engraftment in nonirradiated NSG mice and eliminate complications associated with irradiation. Surprisingly, detectable levels of human CD45(+) cell chimerism were observed after transplantation of cord blood-derived human HSCs into nonirradiated adult as well as newborn NSG mice. However, transgenic expression of human mSCF enabled heightened levels of human hematopoietic cell chimerism in the absence of irradiation. Moreover, nonirradiated NSG-Tg(hu-mSCF) mice engrafted as newborns with human HSCs rejected human skin grafts from a histoincompatible donor, indicating the development of a functional human immune system. These data provide a new immunodeficient mouse model that does not require irradiation preconditioning for human HSC engraftment and immune system development.  相似文献   
70.
Mutations in the nucleophosmin gene (NPM1(mut)) are one of the most frequent molecular alterations in acute myeloid leukemia (AML), and immune responses may contribute to the favorable prognosis of AML patients with NPM1(mut). In the present study, we were able to demonstrate both CD4(+) and CD8(+) T-cell responses against NPM1(mut). Ten peptides derived from wild-type NPM1 and NPM1(mut) were subjected to ELISPOT analysis in 33 healthy volunteers and 27 AML patients. Tetramer assays against the most interesting epitopes were performed and Cr(51)-release assays were used to show the cytotoxicity of peptide-specific T cells. Moreover, HLA-DR-binding epitopes were used to test the role of CD4(+) T cells in NPM1 immunogenicity. Two epitopes (epitopes #1 and #3) derived from NPM1(mut) induced CD8(+) T-cell responses. A total of 33% of the NPM1(mut) AML patients showed immune responses against epitope #1 and 44% against epitope #3. Specific lysis of leukemic blasts was detected. To obtain robust immune responses against tumor cells, the activation of CD4(+) T cells is crucial. Therefore, overlapping (OL) peptides were analyzed in ELISPOT assays and OL8 was able to activate both CD8(+) and CD4(+) T cells. The results of the present study show that NPM1(mut) induces specific T-cell responses of CD4(+) and CD8(+) T cells and therefore is a promising target for specific immunotherapies in AML.  相似文献   
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