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41.
42.
Seasonal incidence of coarctation of the aorta.   总被引:1,自引:0,他引:1       下载免费PDF全文
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43.
Quality of life from the epidemiologic perspective   总被引:4,自引:0,他引:4  
In summary, from the epidemiologic perspective, the conference made it clear that: In modern occurrence research in medicine, quality of life is an important aspect of health outcome, along with duration of life; and it is of interest as a determinant of outcome as well. The concept of quality of life remains ill-defined but is, in the medical sense, some aggregate representation of disability discomfort, and distress resulting from illness and/or medical action. In medicine, quality of life is, in concept, specific to various types of clinical situation; and empirical scales need to be similarly situation-specific. Whereas clinical research on quality of life is already being conducted successfully, further development of scales specific to particular types of clinical situation remains a challenge to theorists of quality of life, as well as to experts on clinimetrics who collaborate with clinical specialists.  相似文献   
44.
In February 1999, an outbreak of listeriosis caused by Listeria monocytogenes serotype 3a occurred in Finland. All isolates were identical. The outbreak strain was first isolated in 1997 in dairy butter. This dairy began delivery to a tertiary care hospital (TCH) in June 1998. From June 1998 to April 1999, 25 case patients were identified (20 with sepsis, 4 with meningitis, and 1 with abscess; 6 patients died). Patients with the outbreak strain were more likely to have been admitted to the TCH than were patients with other strains of L. monocytogenes (60% vs. 8%; odds ratio, 17.3; 95% confidence interval, 2.8-136.8). Case patients admitted to the TCH had been hospitalized longer before cultures tested positive than had matched controls (median, 31 vs. 10 days; P=.008). An investigation found the outbreak strain in packaged butter served at the TCH and at the source dairy. Recall of the product ended the outbreak.  相似文献   
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Dendritic cells (DCs) are the most efficient antigen-presenting cells and thus, have a major role in regulating host immune responses. In the present study, we have analyzed the ability of Gram-positive, pathogenic Streptococcus pyogenes and nonpathogenic Lactobacillus rhamnosus to induce the maturation of human monocyte-derived DCs. Stimulation of DCs with S. pyogenes resulted in strong expression of DC costimulatory molecules CD80, CD83, and CD86 accompanied with a T helper cell type 1 (Th1) cytokine and chemokine response. S. pyogenes also induced interleukin (IL)-2 and IL-12 production at mRNA and protein levels. In addition, IL-23 and IL-27 subunits p40, p19, p28, and EBI3 were induced at mRNA level. In contrast, L. rhamnosus-stimulated DCs showed only moderate expression of costimulatory molecules and produced low levels of cytokines and chemokines. Furthermore, no production of IL-2 or IL-12 family cytokines was detected. Bacteria-induced DC maturation and especially cytokine and chemokine production were reduced when bacteria were heat-inactivated. Our results show that human monocyte-derived DCs respond differently to different Gram-positive bacteria. Although pathogenic S. pyogenes induced a strong Th1-type response, stimulation with nonpathogenic L. rhamnosus resulted in development of semi-mature DCs characterized by moderate expression of costimulatory molecules and low cytokine production.  相似文献   
47.
A promising targeted therapy against NY-ESO-1 (CTAG 1B) using genetically modified T-cells in synovial sarcomas was recently demonstrated in a clinical trial at the NCI. To investigate the role of NY-ESO-1 immunohistochemistry in patient selection and gain better insight into the incidence of NY-ESO-1 expression in synovial sarcomas and other mesenchymal tumors, we evaluated NY-ESO-1 expression by immunohistochemistry in 417 tumors. This collection of samples included: 50 SS18/SSX1/2 fusion positive synovial sarcomas, 155 gastrointestinal stromal tumors (GIST), 135 other spindle cell sarcomas as well as 77 other sarcomas (chondrosarcoma, osteosarcoma, dedifferentiated liposarcoma, alveolar soft part sarcoma, rhabdomyosarcoma, angiosarcoma, malignant mesothelioma, and Ewing's sarcoma). We report that 76% of synovial sarcomas expressed NY-ESO-1 in a strong and diffuse pattern (2-3+, >50-70% of tumor cells). In contrast, only rare cases of other spindle cell mesenchymal tumor expressed NY-ESO-1 (GIST (2/155), malignant peripheral nerve sheath tumors (1/34), and dermatofibrosarcoma protuberans (2/20)). Individual cases of other sarcomas (angiosarcoma, malignant mesothelioma, chondrosarcoma, osteosarcoma, dedifferentiated liposarcoma, alveolar soft part sarcoma, and Ewing's sarcoma) were positive for NY-ESO-1. However, no positive cases were identified amongst our cohort of leiomyosarcomas (0/24), hemangiopericytoma/solitary fibrous tumors (0/40), and cellular schwannomas (0/17). In summary, we find that NY-ESO-1 is strongly and diffusely expressed in a majority of synovial sarcomas, but only rarely in other mesenchymal lesions. Beyond its role in patient selection for targeted therapy, immunohistochemistry for NY-ESO-1 may be diagnostically useful for the distinction of synovial sarcoma from other spindle cell neoplasms.  相似文献   
48.
A novel composite material with an ultra-high strength and a low elastic modulus called carbon fibre-reinforced liquid crystalline polymer (LCP/CF) has been developed. An experimental diaphyseal osteotomy of the proximal femur in fourteen Beagle dogs was fixed with an intramedullary LCP/CF rod of 4.5 mm in diameter and 80 mm in length. The radiological follow-up intervals were 1, 3, 6, 12, 24, 52, and 104 weeks. Five dogs were killed at 1 year and three dogs at 2 years for histological studies; six dogs were retained for longer follow-up. Radiographs showed an uncomplicated healing of the diaphyseal osteotomy with an external callus formation in all dogs in 12 weeks. Histological analysis revealed a benign host tissue response with few inflammatory cells. Both bone and fibrous tissue were seen at the LCP/CF-host tissue interface. The cross-sectional cortical area of the operated femur was slightly greater than that of the control femur in the 2-year follow-up. LCP/CF showed promising properties for high-load applications.  相似文献   
49.
The PAX3–FOXO1 fusion gene is generated by a 2;13 chromosomal translocation and is a characteristic feature of an aggressive subset of rhabdomyosarcoma (RMS). To dissect the mechanism of oncogene action during RMS tumourigenesis and progression, doxycycline‐inducible PAX3–FOXO1 and constitutive MYCN expression constructs were introduced into immortalized human myoblasts. Although myoblasts expressing PAX3–FOXO1 or MYCN alone were not transformed in focus formation assays, combined PAX3–FOXO1 and MYCN expression resulted in transformation. Following intramuscular injection into immunodeficient mice, myoblasts expressing PAX3–FOXO1 and MYCN formed rapidly growing RMS tumours, whereas myoblasts expressing only PAX3–FOXO1 formed tumours after a longer latency period. Doxycycline withdrawal in myoblasts expressing inducible PAX3–FOXO1 and constitutive MYCN following tumour formation in vivo or focus formation in vitro resulted in tumour regression or smaller foci associated with myogenic differentiation and cell death. Following regression, most tumours recurred in the absence of doxycycline. Analysis of recurrent tumours revealed a subset without PAX3–FOXO1 expression, and cell lines derived from these recurrent tumours showed transformation in the absence of doxycycline. The doxycycline‐independent oncogenicity in these recurrent tumour‐derived lines persisted even after PAX3–FOXO1 was inactivated with a CRISPR/Cas9 editing strategy. Whereas cell lines derived from primary tumours were dependent on PAX3–FOXO1 and differentiated following doxycycline withdrawal, recurrent tumour‐derived cells without PAX3–FOXO1 expression did not differentiate under these conditions. These findings indicate that PAX3–FOXO1 collaborates with MYCN during early RMS tumourigenesis to dysregulate proliferation and inhibit myogenic differentiation and cell death. Although most cells in the primary tumours are dependent on PAX3–FOXO1, recurrent tumours can develop by a PAX3–FOXO1‐independent mechanism, in which rare cells are postulated to acquire secondary transforming events that were activated or selected by initial PAX3–FOXO1 expression. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.  相似文献   
50.
Adipose stem cells (ASCs) are an attractive and abundant stem cell source with therapeutic applicability in diverse fields for the repair and regeneration of acute and chronically damaged tissues. Importantly, unlike the human bone marrow stromal/stem stem cells (BMSCs) that are present at low frequency in the bone marrow, ASCs can be retrieved in high number from either liposuction aspirates or subcutaneous adipose tissue fragments and can easily be expanded in vitro. ASCs display properties similar to that observed in BMSCs and, upon induction, undergo at least osteogenic, chondrogenic, adipogenic and neurogenic, differentiation in vitro. Furthermore, ASCs have been shown to be immunoprivileged, prevent severe graft-versus-host disease in vitro and in vivo and to be genetically stable in long-term culture. They have also proven applicability in other functions, such as providing hematopoietic support and gene transfer. Due to these characteristics, ASCs have rapidly advanced into clinical trials for treatment of a broad range of conditions. As cell therapies are becoming more frequent, clinical laboratories following good manufacturing practices are needed. At the same time as laboratory processes become more extensive, the need for control in the processing laboratory grows consequently involving a greater risk of complications and possibly adverse events for the recipient. Therefore, the safety, reproducibility and quality of the stem cells must thoroughly be examined prior to extensive use in clinical applications. In this review, some of the aspects of examination on ASCs in vitro and the utilization of ASCs in clinical studies are discussed.  相似文献   
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