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991.
Haijo Jung Hee-Joung Kim Sang-Ho Lee Sae-Rome Kim Chang Lyong Ji Jung-Han Kim Sun Kook Yoo Ki-Hwang Kim 《Journal of digital imaging》2004,17(2):100-108
This study evaluated the migration to full-PACS of medical image data archived using mini-PACS at two hospitals of the Yonsei University Medical Center, Seoul, Korea. A major concern in the migration of medical data is to match the image data from the mini-PACS with the hospital OCS (Ordered Communication System). Prior to carrying out the actual migration process, the principles, methods, and anticipated results for the migration with respect to both cost and effectiveness were evaluated. Migration gateway workstations were established and a migration software tool was developed. The actual migration process was performed based on the results of several migration simulations. Our conclusions were that a migration plan should be carefully prepared and tailored to the individual hospital environment because the server system, archive media, network, OCS, and policy for data management may be unique. 相似文献
992.
Chung JH Yang JH Song MJ Cho JY Lee YH Park SY Moon MJ Lim HJ Choi JS Kim JO Shin JS Ahn HK Han JY Kim MY Choi KH Ryu HM 《Journal of Korean medical science》2004,19(1):32-36
The aim of present study was to establish normative data for the distribution of nuchal translucency (NT) thickness in normal Korean fetuses. The data were collected from pregnant women with singleton pregnancies in whom fetal ultrasound was performed and the fetal NT thickness was measured between 11 and 14 weeks of gestation. Among them, a total of 2,577 fetuses with a known normal outcome were included in this study. The distribution of multiple of median (MoM) values of the NT thickness with crown-rump length (CRL) in 10-mm intervals and the 95th percentile of MoM were calculated with the linear regression method. The present study showed that NT measurements increase with increasing CRL and a false positive rate increases with increasing gestational age. Therefore, a fixed cut-off point through the first trimester was not appropriate and each NT measurement should be examined according to the gestational age. The present study offers normative data of the fetal NT thickness in a Korean population, which can be used as reference for screening chromosomal aberrations or other congenital abnormalities in the first trimester. 相似文献
993.
Essential role for cyclic AMP and its receptor protein in Yersinia enterocolitica virulence
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Insertion mutations were isolated in cya and crp of Yersinia enterocolitica, which encode adenylate cyclase and the cyclic AMP (cAMP) receptor protein (CRP). The cya and crp mutants were affected for the production of proteins exported by the Ysc, Ysa, and flagellar type III secretion systems (TTSS). Protein production by each TTSS was restored when the respective mutation was complemented by a plasmid-encoded copy of the wild-type gene. Both cya and crp mutants exhibited reduced virulence for orally infected BALB/c mice in a 50% lethal dose analysis. Examination of bacterial survival in host tissues showed that cya and crp mutants colonized Peyer's patches and, to a lesser extent, mesenteric lymph nodes. However, the mutants did not appear to disseminate to the liver and spleen of infected mice. An initial examination of the effectiveness of Y. enterocolitica cya and crp mutants to stimulate protective immunity against subsequent challenge with virulent bacteria in mice was promising. The results indicate that the cAMP-CRP regulatory system is required for Y. enterocolitica virulence. 相似文献
994.
Wan-Ting Huang Luan-Yin Chang Po-Ren Hsueh Chun-Yi Lu Pei-Lan Shao Fu-Yuan Huang Ping-Ing Lee Chun-Ming Chen Chin-Yun Lee Li-Min Huang 《Journal of microbiology, immunology, and infection》2007,40(4):349-354
BACKGROUND AND PURPOSE: Viridans streptococci (VS) are part of the normal flora of humans, but are fast emerging as pathogens causing bacteremia in neutropenic patients. The clinical features, outcomes, and antibiotic susceptibilities of VS bloodstream infections in children with hemato-oncological diseases are reported in this study. METHODS: A retrospective chart review of pediatric patients (< or =18 years) diagnosed with VS infections between January 1998 and December 2004 was conducted at the National Taiwan University Hospital. RESULTS: Among the 26 episodes noted in 25 pediatric patients, the incidence rate of VS bacteremia was found to be significantly higher in pediatric patients with acute myeloid leukemia compared with other hemato-oncological conditions. Most of the patients had profound neutropenia related to chemotherapy for a median of 5 days on the day of positive blood culture. Eight of the 25 patients had undergone stem cell transplantations. Streptococcus mitis was the most common bloodstream isolate and only 12 (44%) of the 27 isolated strains of VS were penicillin-susceptible. Empirical antibiotic treatments were not effective in half of the episodes, but did not affect overall mortality. Isolated bacteremia (63%) and pneumonia (22%) were the two leading clinical presentations. Complications were recognized more frequently in patients with pneumonia. Hypotension and mechanical ventilation each developed in 8 patients (31%). The overall mortality rate was 23%. CONCLUSIONS: Penicillin non-susceptible VS infection has emerged as a threat in children with hemato-oncological diseases, especially those with acute myeloid leukemia. S. mitis is the most common spp. of VS causing bacteremia in children and is associated with serious complications. The development of pneumonia resulted in clinical complications and higher mortality. Empirical antibiotic treatments with activity against the infecting strains did not reduce the overall mortality rate in this study. 相似文献
995.
996.
Cassano P Soares CN Cusin C Mascarini A Cohen LS Fava M 《Psychotherapy and psychosomatics》2005,74(6):362-365
BACKGROUND: We assessed the impact of menopausal status on treatment response and well-being in a cohort of outpatient women with major depressive disorder (DSM-III-R criteria), who received treatment with fluoxetine (20 mg/day for 8 weeks). METHODS: Menopausal status was defined based on age, presence of menstrual irregularity or amenorrhea and vasomotor symptoms. Remission and response of depression were defined as a 17-item Hamilton Depression Rating Scale (HAM-D-17) score or=50%, respectively. Well-being was assessed by self-rating with the Symptom Questionnaire. Remitters were followed up for 28 additional weeks. RESULTS: No differences in rates of response and remission as well as in levels of well-being were observed among pre- (n = 121), peri- (n = 28) and postmenopausal (n = 35) women at the endpoint of the acute phase, even after adjustment for baseline depression severity. Residual symptoms, however, were significantly more common in postmenopausal women, except for the continuation phase endpoint. Differences in residual symptoms during the acute phase subsided after adjustment for baseline depression severity. CONCLUSIONS: Overall, menopausal status did not significantly affect the response to fluoxetine treatment and the degree of posttreatment well-being among major depressive disorder patients. 相似文献
997.
Vascular endothelial growth factor and basic fibroblast growth factor induce expression of CXCR4 on human endothelial cells: In vivo neovascularization induced by stromal-derived factor-1alpha 总被引:3,自引:0,他引:3
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Salcedo R Wasserman K Young HA Grimm MC Howard OM Anver MR Kleinman HK Murphy WJ Oppenheim JJ 《The American journal of pathology》1999,154(4):1125-1135
The contribution of chemokines toward angiogenesis is currently a focus of intensive investigation. Certain members of the CXC chemokine family can induce bovine capillary endothelial cell migration in vitro and corneal angiogenesis in vivo, and apparently act via binding to their receptors CXCR1 and CXCR2. We used an RNAse protection assay that permitted the simultaneous detection of mRNA for various CXC chemokine receptors in resting human umbilical vein endothelial cells (HUVECs) and detected low levels of only CXCR4 mRNA. Stimulation of HUVECs with vascular endothelial growth factor (VEGF) or basic fibroblast growth factor (bFGF) up-regulated levels of only CXCR4 mRNA. CXCR4 specifically binds the chemokine stromal-derived factor-1alpha (SDF-1alpha). Competitive binding studies using 125I-labeled SDF-1alpha with Scatchard analysis indicated that VEGF or bFGF induced an average number of approximately 16,600 CXCR4 molecules per endothelial cell, with a Kd = 1.23 x 10(-9) mol/L. These receptors were functional as HUVECs and human aorta endothelial cells (HAECs) migrated toward SDF-1alpha. Although SDF-1alpha-induced chemotaxis was inhibited by the addition of a neutralizing monoclonal CXCR4 antibody, endothelial chemotaxis toward VEGF was not altered; therefore, the angiogenic effect of VEGF is independent of SDF-1alpha. Furthermore, subcutaneous SDF-1alpha injections into mice induced formation of local small blood vessels that was accompanied by leukocytic infiltrates. To test whether these effects were dependent on circulating leukocytes, we successfully obtained SDF-1alpha-induced neovascularization from cross sections of leukocyte-free rat aorta. Taken together, our data indicate that SDF-1alpha acts as a potent chemoattractant for endothelial cells of different origins bearing CXCR4 and is a participant in angiogenesis that is regulated at the receptor level by VEGF and bFGF. 相似文献
998.
Expression of sialyl-Lewis X, an E-selectin ligand, in inflammation, immune processes, and lymphoid tissues. 总被引:1,自引:0,他引:1
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J. M. Munro S. K. Lo C. Corless M. J. Robertson N. C. Lee R. L. Barnhill D. S. Weinberg M. P. Bevilacqua 《The American journal of pathology》1992,141(6):1397-1408
The carbohydrate structure sialyl-Lewis X (SLex) can function as a ligand for E-selectin, formerly known as endothelial leukocyte adhesion molecule-1 (ELAM-1). This study was performed to analyze the expression of SLex by leukocytes and other cell types in the context of inflammatory and immune processes. Human peripheral blood cells were examined by flow cytometry using monoclonal antibody CSLEX1 directed against SLex. Cell surface SLex was found in abundance on nearly all isolated polymorphonuclear leukocytes (PMN) and monocytes, and at low levels on a substantial portion (up to 40%) of natural killer cells. This moiety was expressed also on approximately 10% of peripheral blood T cells. Immunohistochemistry was performed on various human tissues involved in inflammatory or immune processes and on secondary lymphoid tissues. In acute appendicitis, endothelial cells of postcapillary venules expressed E-selectin, and most PMN, both within vessels and extravasated, expressed SLex. A substantial number of monocytes/macrophages in inflamed appendiceal, synovial, and dermal tissues also reacted with antibody CSLEX1; however, only rare tissue macrophages in uninflamed nonlymphoid sites showed expression of SLex. These observations are consistent with the concept that SLex on circulating PMN and monocytes functions as a ligand for endothelial E-selectin in the development of inflammatory reactions. SLex-positive lymphocytes also were seen, notably, T lymphocytes in inflamed skin. An unexpected finding was that the CSLEX1 antibody also reacted with venular endothelium in certain lymphoid tissues and in inflamed appendix, but not with endothelium in normal appendix. Whether the SLex antigen identified on endothelium represents de novo expression or passive adsorption remains to be determined. 相似文献
999.
AIM--To determine the prevalence of a biochemically detectable hypercoagulable state, defined in terms of increased thrombin or plasmin generation, in patients with phenotypically characterised thrombophilia. METHODS--Plasma concentrations of the prothrombin activation peptide F1.2 and fibrin degradation (FbDP) and fibrinogen degradation products (FgDP) were measured by enzyme immunoassay in 104 patients deficient in natural anticoagulants, and 35 unaffected relatives. RESULTS--Increased concentrations of F1.2, FbDP, and FgDP were present in 18, 25, and 19 of 104 patients, respectively. There were no correlations between F1.2, FbDP, and FgDP concentrations, or between these parameters and concentrations of natural anticoagulants except for a negative correlation between protein C concentrations and FgDP (rho = -0.46, p = 0.009). CONCLUSION--A biochemically detectable hypercoagulable state is present in some patients with asymptomatic thrombophilia. Markers of plasmin generation may be increased more frequently in thrombophilia than markers of thrombin generation. This finding should prompt the inclusion of markers of plasmin generation in prospective longitudinal cohort studies to determine the predictive value of a hypercoagulable state, defined by either excessive thrombin or plasmin generation, for the development of venous thromboembolism. 相似文献
1000.
We studied the relationship between light intensity and cell response to various wavelengths and wavelength combinations in the dorsal, parvocellular layers of the macaque lateral geniculate nucleus. When response is plotted as a function of the logarithm of stimulus intensity, the slope and shape of curves depends on wavelength. For wavelengths near the crossover point between excitatory and suppressive responses, nonmonotonic curves are common. Consequently, the form of spectral-response functions depends on stimulus intensity. Responses to combined stimuli made up of wavelengths close together near one spectral extreme are approximately additive. If one wavelength is near the crossover point, responses are nonadditive so that a midspectral wavelength, only producing a weak excitatory response, is able to occlude more vigorous responses to wavelengths near the spectral ends. Responses of parvocellular layer cells are consistent with their being a result of linear interaction of opponent cone mechanisms, the response of each of which follows a modified hyperbolic tangent function (22). Responses to all wavelength combinations, even those showing strikingly nonadditive effects, could be predicted from the additive opponent model described above. 相似文献