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An unusual retinal manifestation of arteriovenous communications is reported in a case showing a combination of Sturge-Weber and Kippel-Trenaunay syndromes. The arteriovenous communications are thought to be similar to those seen in the limbs in Parkes-Weber syndrome. This retinal finding indicates that the three syndromes are intricately related to each other and may be an incomplete manifestation of a single pathophysiologic entity which may be named neurocutaneous angiomatosis. 相似文献
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Cardiovascular diseases (CVD) among non-communicable diseases are already a major public health challenge worldwide. A further increase in CVD is projected to occur over the next 25 years as a result of both adverse lifestyle changes and demographic shifts in the population age profile. The adverse impact of these health problems will affect women in particular, given the steady rise in the proportion of the aging population that will be women.The critical issue presently in the management of CVD is that we are not even adequately using the data that are available. Women still remain unaware that they are at risk, and information about women is not easily accessible to their physicians. This is a global issue and the need remains for worldwide initiatives with greater vigilance to identify these factors and make efforts to control them effectively.Currently, in scientific research, it is expected that the results of clinical research be analyzed for sex differences, sex- and gender-appropriateness, and sex- and gender-specific approaches for prevention, diagnosis, treatment, and counseling. To address the care discrepancy, the global community needs to develop a conducive environment within a comprehensive policy and operational framework to achieve favorable lifestyles, and CVD risk factor reduction for both men and women. 相似文献
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Typhus and typhuslike rickettsiae associated with opossums and their fleas in Los Angeles County, California. 下载免费PDF全文
S G Williams J B Sacci Jr M E Schriefer E M Andersen K K Fujioka F J Sorvillo A R Barr A F Azad 《Journal of clinical microbiology》1992,30(7):1758-1762
The recent discovery of cat fleas (Ctenocephalides felis) infected with a typhuslike rickettsia (designated the ELB agent) raises the question of whether similar rickettsial infections exist in wild cat flea populations. We verified the presence of the ELB agent and Rickettsia typhi in urban and suburban areas of Los Angeles, Calif. Opossums trapped in close proximity to the residences of human murine typhus cases in Los Angeles county and other areas within the city of Los Angeles were tested for the presence of typhus group rickettsiae by the polymerase chain reaction (PCR). The presence of rickettsiae in the spleen tissues of three opossums (n = 9) and in 66 opossum fleas (n = 205) was determined by PCR and was verified by dot blot and Southern transfer hybridization. Further analysis of the amplified PCR products generated by a series of primer pairs derived from either the 17-kDa antigen gene or the citrate synthase gene revealed that both R. typhi and the ELB agent were present in the tested samples. Dual infection was not noted in the samples; however, the fleas were infected with either R. typhi or the ELB agent. The presence of the ELB agent in the cat flea population may have implications for public health. Whether this agent is responsible for the mild cases of human murine typhus in urban and suburban areas of Los Angeles or in other endemic foci remains to be determined. 相似文献
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Rickettsia-macrophage interactions: host cell responses to Rickettsia akari and Rickettsia typhi 下载免费PDF全文
Radulovic S Price PW Beier MS Gaywee J Macaluso JA Azad A 《Infection and immunity》2002,70(5):2576-2582
The existence of intracellular rickettsiae requires entry, survival, and replication in the eukaryotic host cells and exit to initiate new infection. While endothelial cells are the preferred target cells for most pathogenic rickettsiae, infection of monocytes/macrophages may also contribute to the establishment of rickettsial infection and resulting pathogenesis. We initiated studies to characterize macrophage-Rickettsia akari and -Rickettsia typhi interactions and to determine how rickettsiae survive within phagocytic cells. Flow cytometry, microscopic analysis, and LDH release demonstrated that R. akari and R. typhi caused negligible cytotoxicity in mouse peritoneal macrophages as well as in macrophage-like cell line, P388D1. Host cells responded to rickettsial infection with increased secretion of proinflammatory cytokines such as interleukin-1beta (IL-1beta) and IL-6. Furthermore, macrophage infection with R. akari and R. typhi resulted in differential synthesis and expression of IL-beta and IL-6, which may correlate with the existence of biological differences among these two closely related bacteria. In contrast, levels of gamma interferon (IFN-gamma), IL-10, and IL-12 in supernatants of infected P388D1 cells and mouse peritoneal macrophages did not change significantly during the course of infection and remained below the enzyme-linked immunosorbent assay cytokine detection limits. In addition, differential expression of cytokines was observed between R. akari- and R. typhi-infected macrophages, which may correlate with the biological differences among these closely related bacteria. 相似文献
6.
The host response to bites of the oriental rat flea, Xenopyslla cheopis Rothschild, was investigated by examining rat blood leucocyte kinetics, histopathology, and the effect that the host response had upon subsequent flea feeding and longevity. Test rats were subjected to controlled exposures of fleas, and leucocyte data from test rats were compared to those of unexposed controls. Of the five leucocyte types examined, only the basophil appeared to play a role in the host blood response to flea bites. Significant increases in blood basophil levels occurred 2-3 d after exposure but subsided to control levels within a week. However, flea feeding did not produce histopathology at the flea feeding sites nor did the basophilic blood response of rats affect subsequent feeding or longevity of the fleas. 相似文献
7.
Gastrointestinal stromal tumors (GISTs)--the Lebanese experience 总被引:1,自引:0,他引:1
Salamoun W El Hajj G Aftimos G Moukharbel N Khairallah S Bejjani N Abou Sleiman CH Abou Atmeh J Azar H Elias E Abi Gerges D 《Molecular immunology》2003,39(17-18):1129-1132
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C G Espinoza S G Pillarisetti H A Azar 《Annals of clinical and laboratory science》1984,14(6):467-473
Tumor cell marker antibodies were used to analyze ten cases of hepatocellular carcinoma associated with cirrhosis. Clinically, eight of these cases gave a history of chronic alcoholism and the other two of hepatitis B virus infection. Formalin-fixed, paraffin-embedded sections from these cases were screened with antibodies against alpha fetoprotein (AFP), hepatitis B surface antigen (HBsAg) and carcinoembryonic antigen (CEA) using the peroxidase antiperoxidase and avidin-biotin immunoperoxidase procedures. Three cases were positive for AFP, four for HBsAg, and three for CEA; two cases had both HBsAg and CEA. Alpha fetoprotein was present only in the cytoplasm of tumor cells in three cases. Hepatitis B surface antigen, on the other hand, was present in the cytoplasm of hepatocytes in cirrhotic areas and, in one out of the four cases, was also present in hepatocellular carcinoma cells. Carcinoembryonic antigen was seen in three cases; it was present on the surface and in the cytoplasm of proliferating ducts within the cirrhotic areas and between cell surfaces of individual tumor cells in two cases. The presence of different markers was not related to the microscopic appearance of the tumors. In one case, positivity for AFP was of diagnostic help in a tissue sample obtained by needle biopsy. The avidin-biotin immunoperoxidase procedure was more sensitive than the peroxidase antiperoxidase (PAP technique in the pathological assessment of autopsy specimens. Our findings are in agreement with those of other reports and indicate that AFP and HBsAg are the most commonly found markers in hepatoma associated with cirrhosis, and that CEA staining is variable and hepatoma associated with cirrhosis, and that CEA staining is variable and probably non-contributory. 相似文献